Thermoplastic molding compositions comprising, as substantive constituents

The invention relates to thermoplastic molding compositions comprising, as substantive constituents,
A) from 5 to 95% by weight of a vinylaromatic polymer having a syndiotactic structure,
B) from 2 to 50% by weight of an inorganic filler,
C) from 1 to 45% by weight of an elastomeric, particulate graft polymer,
D) from 1 to 10% by weight of a compatibilizer, and, where appropriate,
E) from 1 to 45% by weight of an elastomeric particulate styrene-diene block copolymer whose diene fraction may have been completely or to some extent hydrogenated, and, where appropriate,
F) from 1 to 35% by weight of a thermoplastic elastomer based on copolymers made from vinylaromatic monomers, dienes, and, where appropriate, 1,1-diphenylethylene, and, where appropriate,
G) additives,
where the total of the percentages by weight of A) to G) is 100.
The invention further relates to the use of the thermoplastic molding compositions for producing fibers, films or moldings, and also to the resultant fibers, films and moldings.
Due to its crystallinity, syndiotactic polystyrene has a very high melting point of about 270xc2x0 C., high stiffness and tensile strength, dimensional stability, a low dielectric constant and high chemicals resistance. Its mechanical property profile is even retained at temperatures above its glass transition temperature. The preparation of syndiotactic polystyrene in the presence of metallocene catalyst systems is known and described in detail in EP-A 0 535 582, for example.
The field of application of syndiotactic polystyrene is severely restricted by its brittleness.
There has therefore been a desire to reduce the brittleness of syndiotactic polystyrene, also termed SPS below, while at the same time improving its impact strength, breaking stress and stiffness.
EP-A 0 779 329 (Idemitsen Kosan) and WO-A 941 24 206 (Dow) have disclosed polymer blends made from syndiotactic polystyrene, from inorganic fillers, from polyphenylene ether and from a rubber component. However, the properties of the blends are still unsatisfactory, for example low flowability and complicated preparation.
EP-A 755 972 describes SPS which has been impact-modified using a mixture of, on the one hand, a block copolymer made from styrene and from hydrogenated butadiene and, on the other hand, a core-shell polymer with a butadiene polymer core. Molding compositions with inorganic fillers are not disclosed.
It is an object of the present invention, therefore, to prepare a thermoplastic molding composition which is based on vinylaromatic polymers with a syndiotactic structure and which combines high impact strength, high stiffness (modulus of elasticity), and good flowability (MVR, processability) and breaking stress.
We have found that this object is achieved by means of the thermoplastic molding compositions defined at the outset.
The use of the thermoplastic molding compositions for producing fibers, films or moldings has also been found, as have the resultant fibers, films and moldings.
As component A), the thermoplastic molding compositions of the invention comprise from 5 to 95% by weight, preferably from 20 to 80% by weight, in particular from 40 to 70% by weight, of a vinylaromatic polymer having a syndiotactic structure. The expression xe2x80x9chaving a syndiotactic structurexe2x80x9d means for the purposes of the present invention that the polymers are substantively syndiotactic, i.e. the syndiotactic content determined by 13C NMR is above 50%, preferably above 60%, of mmmm pentads.
Component A) has preferably been built up from compounds of the formula I
where:
R1 is hydrogen or C1- to C4-alkyl, and
R2 to R6 independently of one another, are hydrogen, C1- to C12-alkyl, C6- to C18-aryl, or halogen, or where two adjacent radicals together are a cyclic group having from 4 to 15 carbon atoms, such as C4-C8-cycloalkyl, or anellated ring systems.
It is preferable to use vinylaromatic compounds of the formula I where
R1 is hydrogen.
Particular substituents R2 to R6 which may be used are hydrogen, C1- to C4-alkyl, chlorine, phenyl, biphenyl, naphthalene or anthracene. Two adjacent radicals together may also be a cyclic group having from 4 to 12 carbon atoms, examples of resultant compounds of the formula I being naphthalene derivatives or anthracene derivatives.
Examples of these preferred compounds are:
Styrene, p-methylstyrene, p-chlorostyrene, 2,4-dimethylstyrene, 4-vinylbiphenyl, vinylnaphthalene and vinylanthracene.
It is also possible to use mixtures of various vinylaromatic compounds, but it is preferable to use just one vinylaromatic compound.
Particularly preferred vinylaromatic compounds are styrene and p-methylstyrene.
Mixtures of various vinylaromatic polymers with a syndiotactic structure may also be used as component A), but it is preferable to use just one vinylaromatic polymer, in particular syndiotactic polystyrene (SPS).
Vinylaromatic polymers (A) with a syndiotactic structure and processes for their preparation are known per se and are described in EP-A 535 582, for example. The preferred method of preparation is to react compounds of the general formula I in the presence of a metallocene complex and of a cocatalyst. Particular metallocene complexes used are pentamethylcyclopentadienyltitanium trichloride, pentamethylcyclopentadienyltrimethyltitanium, and pentamethylcyclopentadienyltitanium trimethylate.
The vinylaromatic polymers with a syndiotactic structure generally have a molar mass Mw (weight-average) of from 5 000 to 10 000 000 g/mol, in particular from 10 000 to 2 000 000 g/mol. The polydispersities Mw/Mn are generally from 1.1 to 30, preferably from 1.4 to 10.
Other vinylaromatic polymers which may be used as component A) and have a syndiotactic structure are star polymers based on vinylaromatic monomers. Examples of these star polymers are described in the earlier German Patent Application 196 34 375.5-44, in particular on page 2, line 21 to page 6, line 25, and in the examples.
As component B), the molding compositions of the invention comprise from 2 to 50% by weight, preferably from 5 to 45% by weight, in particular from 15 to 42% by weight, of fibers or particulate inorganic fillers or mixtures of these.
Examples of these are carbon fibers, glass fibers, glass mats, glass silk rovings or glass beads, or else potassium titanate whiskers, preferably glass fibers. Glass fibers may have been provided with a size or with a coupling agent. These glass fibers may be incorporated either as short glass fibers or else as continuous-filament strands (rovings). Preferred glass fibers comprise an aminosilane size and typically have a diameter D of from 1 to 30 xcexcm, preferably from 3 to 20 xcexcm, in particular from 5 to 15 xcexcm. In the extruded molding composition of the invention the glass fibers then have a length-to-diameter ratio of from 5 to 100, preferably from 10 to 80, in particular from 15 to 50.
Examples of other materials which may be used as component B) are amorphous silica, magnesium carbonate, powdered quartz, mica, talc, feldspar or calcium silicates.
The elastomeric, particulate graft polymer C) has been built up from
c1) from 30 to 100% by weight, preferably from 40 to 85% by weight, particularly preferably from 45 to 80% by weight, of a phase prepared by emulsion polymerization of
c1.1) from 70 to 100% by weight, preferably from 70 to 99.8% by weight, particularly preferably from 75 to 99.5% by weight, of an acrylate, and
c1.2) from 0 to 10% by weight, preferably from 0.2 to 6% by weight, particularly preferably from 0.5 to 5% by weight, of another monomer having two or more polymerizable double bonds, and
c1.3) from 0 to 30% by weight, preferably from 0 to 29.8% by weight, particularly preferably from 0 to 24.5% by weight, of other polymerizable monomers, and
c2) from 10 to 70% by weight, preferably from 30 to 60% by weight, particularly preferably from 30 to 55% by weight, of at least one other phase, prepared by polymerization in the presence of the first phase c1) of
c2.1) from 80 to 100% by weight, preferably from 90 to 100% by weight of styrene, and
c2.2) from 0 to 20% by weight, preferably from 0 to 10% by weight, of other monomers.
The phase c1) of the crosslinked rubber c) preferably has a glass transition temperature from  less than 0xc2x0 C., preferably  less than xe2x88x9210xc2x0 C., particularly preferably  less than xe2x88x9215xc2x0 C., and has been built up predominantly from acrylates (c1.1), in particular butyl acrylate and/or ethylhexyl acrylate. This rubber phase c1) may contain other monomers c1.3), in particular methacrylates, styrene and/or acrylonitrile, and also polyfunctional crosslinking monomers c1.2), preferably selected from the following group: divinylbenzene, diallyl maleate, diallyl fumarate, diallyl phthalate, allyl methacrylate, triallyl isocyanurate, butadiene, isoprene, and dihydrocyclopentadienyl acrylate, particularly preferably dihydrocyclopentadienyl acrylate.
The rubber phase c1) is prepared by emulsion polymerization of the monomers, or by miniemulsion polymerization.
The rubber c) has at least one other phase, prepared by polymerization of
c2.1) from 80 to 100% by weight, preferably from 90 to 100% by weight, of styrene, and
c2.2) from 0 to 20% by weight of other monomers, in the presence of the first phase.
Suitable other monomers are the substances listed for c1.1) and c1.3) as other monomers for the first phase. The second phase c2) is generally the outer phase of the rubber c), that is to say the rubber c) is generally a core-shell polymers, but it is not essential for this structure to be present.
The rubber c) may also have other polymeric phases, in particular made from polystyrene and from its copolymers, preferably from polystyrene, and from crosslinkers and/or from grafting monomers. These phases may be outer shells, or else may form the cores of the multiphase rubber particles c).
The amount of component C) in the molding compositions of the invention is from 1 to 45% by weight, preferably from 1 to 35% by weight, and in particular from 1 to 20% by weight.
The median particle size D50 is from 50 to 160 nm, preferably from 70 to 150 nm.
As component D), the thermoplastic molding compositions of the invention comprise from 1 to 10% by weight, preferably from 1 to 8% by weight, in particular from 2.5 to 5% by weight, of a compatibilizer which as far as is known at present brings about the coupling to the inorganic filler B). Substances known from the literature may be used, in particular polyarylene ethers.
Polyarylene ethers, and also processes for their preparation, are known per se and are described in DE-A 42 19 438, for example. Among the polyarylene ethers, polyphenylene ethers are particularly suitable, especially polyphenylene ethers modified with polar groups. These polyphenylene ethers modified with polar groups, and also processes for their preparation, are also known per se and are described in DE-A 41 29 499, for example.
The compounds preferably used as component D) are polyphenylene ethers modified with polar groups and built up from
d1) from 70 to 99.95% by weight of a polyphenylene ether,
d2) from 0 to 25% by weight of a vinylaromatic polymer, and
d3) from 0.05 to 5% by weight of at least one compound which contains at least one double or triple bond and at least one functional group selected from the class consisting of carboxylic acids, carboxylic esters, carboxylic anhydrides, carboxamides, epoxides, oxazolines and urethanes.
Examples of polyphenylene ethers d1) are poly(2,6-dilauryl-1,4-phenylene) ether, poly(2,6-diphenyl-1,4-phenylene) ether, poly(2,6-dimethoxy-1,4-phenylene) ether, poly(2,6-diethoxy-1,4-phenylene) ether, poly(2-methoxy-6-ethoxy-1,4-phenylene) ether, poly(2-ethyl-6-stearyloxy-1,4-phenylene) ether, poly(2,6-dichloro-1,4-phenylene) ether, poly(2-methyl-6-phenyl-1,4-phenylene) ether, poly(2,6-dibenzyl-1,4-phenylene) ether, poly(2-ethoxy-1,4-phenylene) ether, poly(2-chloro-1,4-phenylene) ether, and poly(2,5-dibromo-1,4-phenylene) ether.
It is preferable to use polyphenylene ethers whose substituents are alkyl having from 1 to 4 carbon atoms, for example poly(2,6-dimethyl-1,4-phenylene) ether, poly(2,6-diethyl-1,4-phenylene) ether, poly(2-methyl-6-ethyl-1,4-phenylene) ether, poly(2-methyl-6-propyl-1,4-phenylene) ether, poly(2,6-dipropyl-1,4-phenylene) ether and poly(2-ethyl-6-propyl-1,4-phenylene) ether.
Examples of preferred vinylaromatic polymers d2) can be found in the monograph by Olabisi, pp. 224 to 230 and 245. Merely as examples, mention may be made here of vinylaromatic polymers made from styrene, chlorostyrene, xcex1-methylstyrene or p-methylstyrene. Subordinate amounts (preferably not more than 20% by weight, in particular not more than 8% by weight, of comonomers, such as (meth)acrylonitrile or (meth)acrylates, may also be involved in the structure. Particularly preferred vinylaromatic polymers are polystyrene and impact-modified polystyrene. It is, of course, also possible to use a mixture of these polymers. The preparation process is preferably that described in EP-A 302 485.
Examples of suitable modifiers d3) are maleic acid, methylmaleic acid, itaconic acid, tetrahydrophthalic acid, anhydrides and imides thereof, fumaric acid, the mono- and diesters of these acids, e.g. of C1- and C2- to C8-alkanols, the mono- and diamides of these acids, such as N-phenylmaleimide and maleic hydrazide.
Other examples which may be mentioned are N-vinylpyrrolidone and (meth)acryloylcaprolactam.
The elastomeric component E) made from a styrene-diene block copolymer whose diene content may have been completely or to some extent hydrogenated is known, for example from EP-A 755 972, and commercially available, for example as Kraton(copyright) G 1651 from Shell, and other examples are Cariflex(copyright)-TR grades (Shell), Finaprene(copyright) grades (Fina) and Europrene(copyright) grades (Enichen).
As component F), the thermoplastic molding compositions of the invention comprise, where appropriate, from 1 to 35% by weight, preferably from 1 to 20% by weight, in particular from 1 to 15% by weight, of copolymers made from vinylaromatic monomers, from 1,1-diphenylethylene and, where appropriate, from dienes. This component F) may also be termed a thermoplastic elastomer (TPE).
Component F) is preferably prepared by anionic polymerization.
Particularly preferred components F) are three-block copolymers, particularly those which have been hydrogenated. The copolymers used as component F) are preferably those prepared from styrene, 1,1-diphenylethylene and butadiene, in particular styrene (S)/1,1-diphenylethylene (DPE)-butadiene-S/DPE three-block copolymers, the butadiene block having been hydrogenated (EB), i.e. (S/DPE)-EB-(S/DPE).
Other suitable copolymers or block copolymers have at least one block A made from vinylaromatic monomers a1) and 1,1-diphenylethylene or its derivatives a2) substituted on the aromatic rings, where appropriate, with alkyl groups having up to 22 carbon atoms, and are obtainable by anionic polymerization, the copolymer or the block A having been formed by using an initiating solution composed of the product from reaction of an anionic polymerization initiator with at least the equimolar amount of monomers a2).
It is preferable to prepare block copolymers having at least one block A and having at least one, where appropriate hydrogenated, block B made from dienes b), using sequential anionic polymerization, by carrying out the following steps in succession:
I) Forming a block A by
I.1) preparing an initiating solution composed of the product from reaction of an anionic polymerization initiator with at least the equimolar amount of monomers a2),
I.2) adding any remaining amount of monomers a2) and from 60 to 100% of the total amount of monomers a1),
I.3) adding any remaining amount of monomers a1) when the conversion of the monomers added in the preceding steps has reached at least 80%,
xe2x80x83the concentration of the polymerization solution after the final addition of monomer being at least 35% by weight,
II) and then forming a block B by
II.1) adding an additive which affects the polymerization parameters, and
II.2) adding the dienes b), and
xe2x80x83where appropriate, carrying out the following steps:
III) adding a chain terminator or coupling agent,
IV) hydrogenating the block copolymer,
V) isolating and working-up the block copolymers in a manner known per se, and
VI) adding stabilizers.
The copolymers or the blocks A are composed of vinylaromatic monomers a1) and 1,1-diphenylethylene or its derivatives a2) substituted on the aromatic rings, where appropriate, with alkyl groups having up to 22 carbon atoms, preferably having from 1 to 4 carbon atoms, such as methyl, ethyl, isopropyl, n-propyl or n-, iso- or tert-butyl. Preferred vinylaromatic monomers a1) are styrene and its derivatives substituted at an xcex1 position or on the aromatic ring with from 1 to 4 carbon atoms, for example xcex1-methylstyrene, p-methylstyrene, ethylstyrene, tert-butylstyrene or vinyltoluene. Unsubstituted 1,1-diphenylethylene itself is particularly preferably used as monomer a2). The molar ratio of the units which derive from 1,1-diphenylethylene or its derivatives a2) to units which derive from the vinylaromatic monomer a1) is generally from 1:1 to 1:25, preferably from 1:1.05 to 1:10, and particularly preferably from 1:1.1 to 1:3.
The copolymers or the blocks A preferably have a random structure, and their molecular weight Mw is generally from 1 000 to 500 000, preferably from 3 000 to 100 000, particularly preferably from 4 000 to 30 000.
In principle any diene is suitable as diene b) for the block B, but preference is given to those having conjugated double bonds, for example 1,3-butadiene, isoprene, 2,3-dimethylbutadiene, 1,3-pentadiene, 1,3-hexadiene, phenylbutadiene, piperylene and mixtures of these. Particular preference is given to the use of 1,3-butadiene or isoprene. The diene block may have been partially or completely hydrogenated, or be unhydrogenated. The hydrogenation of polyisoprene blocks gives ethylene-propylene blocks, and that of polybutadiene blocks gives polyethylene blocks or polyethylene-butylene blocks as determined by the 1,2-vinyl content of the unhyrogenated butadiene block. The hydrogenation makes the block copolymers more thermally stable and especially more resistant to aging and to weathering. The molecular weights Mw of the blocks B are generally from 10 000 to 500 000, preferably from 20 000 to 350 000, and particularly preferably from 20 000 to 200 000. The glass transition temperatures of the blocks B are generally below xe2x88x9230xc2x0 C., preferably below xe2x88x9250xc2x0 C.
The proportion by weight of the total of all of the blocks A, based on the entire block copolymer, is generally from 5 to 95% by weight, preferably from 5 to 50% by weight, particularly preferably from 25 to 35% by weight.
The anionic polymerization is initiated using organometallic compounds. The initiators used may be the usual alkali metal alkyl compounds or alkali metal aryl compounds. It is advantageous to use organolithium compounds, such as ethyl-, propyl-, isopropyl-, n-butyl-, sec-butyl-, tert-butyl-, phenyl-, hexylbiphenyl-, hexamethylenedi-, butadieneyl-, isopreneyl- or polystyryllithium. Particular preference is given to the use of 1,1-diphenylhexyllithium, which is easily obtainable from the reaction of 1,1-diphenylethylene with n- or sec-butyllithium. The amount of initiator needed is calculated from the desired molecular weight and is generally from 0.002 to 5 mol percent, based on the amount of monomer to be polymerized.
Suitable solvents are solvents inert toward the organometallic initiator. It is advantageous to use aliphatic, cycloaliphatic or aromatic hydrocarbons having from 4 to 12 carbon atoms, such as pentane, hexane, heptane, cyclopentane, cyclohexane, methylcyclohexane, decalin, isooctane, benzene, alkylbenzenes, such as toluene, xylene or ethylbenzene, or suitable mixtures.
Once the build-of of molecular weight has ended, the xe2x80x9cliving growthxe2x80x9d ends of the polymer may, if desired, be reacted with conventional chain terminators or with conventional coupling agents, the amounts of which usually depend on the amount of initiator used.
Suitable chain terminators are protonating substances or Lewis acids, such as water, alcohols, aliphatic or aromatic carboxylic acids, or else inorganic acids, such as carbonic acid, phosphoric acid or boric acid.
For coupling of the block copolymers, use may be made of bi- or polyfunctional compounds, for example halides of aliphatic or araliphatic hydrocarbons, such as 1,2-dibromoethane, bischloromethylbenzene, or silicon tetrachloride, dialkyl- or diarylsilicon dichloride, alkyl- or arylsilicon trichloride, tin tetrachloride, polyfunctional aldehydes, such as terephthalic dialdehyde, ketones, esters, anhydrides or epoxides. If the block copolymer is not being hydrogenated, preferred coupling agents used are carboxylic esters, such as ethyl acetate. For hydrogenated block copolymers, it is preferable to use 1,2-dibromoethane or diepoxides, in particular diglycidyl ethers, such as 1,4-butanediol diglycidyl ether.
Examples of an additive (randomizer) used which affect polymerization parameters are Lewis bases, such as polar, aprotic solvents, and metal salts soluble in hydrocarbons. Examples of Lewis bases which may be used are dimethyl ether, diethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran, tetrahydrofurfuryl ethers, such as tetrahydrofurfuryl methyl ether, and tertiary amines, such as pyridine, trimethylamine, triethylamine and tributylamine, and peralkylated bi- or oligoamines, such as tetramethylethylenediamine. These are usually used at concentrations of from 0.1 to 5 percent by volume, based on the solvent. Among the metal salts soluble in hydrocarbons, it is preferable to use the alkali metal or alkaline earth metal salts of primary, secondary, or especially tertiary alcohols, particularly preferably the potassium salts, such as potassium triethylcarbinolate or potassium tetrahydrolinaloolate. The molar ratio of metal salt to initiator is usually from 1:5 to 1:200, preferably from 1:30 to 1:100.
The selection of the randomizer and its amount depend on the desired final product. For polymers not intended for hydrogenation and if, for example, when using butadiene, a high 1,4-vinyl content is desired, it is preferable to use a potassium salt soluble in hydrocarbons. For polymers which are intended for subsequent hydrogenation it is preferable to use tetrahydrofuran. The amount used here is such that if butadiene is used, for example, the resultant 1,2-vinyl content is from about 20 to 50%.
In this process the entire amount of the monomers a2) preferably forms an initial charge in a solvent and is mixed with the polymerization initiator. However, it is also possible for some part of the monomers a2) or of the solvent not to be added until later. The amount of polymerization initiator is calculated by taking the amount calculated from the desired molecular weight and from the total amount of monomer to be polymerized, and adding an amount calculated from any protic contaminants which may be present in monomers or solvent and which can be removed by titration to an end-point. It is preferable to use n- or sec-butyllithium, which reacts completely with the monomers a2) within a few hours, generally from 0.5 to 40 hours at from 20 to 70xc2x0 C., to give 1,1-diphenylhexyllithium or, respectively, the corresponding substituted derivatives. The temperature of the initial charge is preferably controlled at from 40 to 70xc2x0 C. while from 60 to 100%, preferably from 70 to 90%, of the entire amount of monomers a1) needed to form the block A is fed. The feed time depends on the reactivity of the monomers used and on the concentration, and is generally from 0.5 to 10 hours at from 40 to 70xc2x0 C. The addition of the remaining amount of the monomers a1) generally takes place after conversion has exceeded 80%, preferably has exceeded 95%, of the monomers which form the initial charge or have been added by that time. Block A is polymerized at high monomer concentration, and it is possible here to achieve a reduction in the amount of residual monomers a2). The concentration of the polymerization solution after the final addition of monomer is generally at least 35% by weight, particularly preferably more than 50% by weight.
In preparing the block copolymers with at least one block B, a block A is first formed as described above, followed by a block B, by sequential anionic polymerization.
After formation of the A block and prior to addition of the dienes b), the additive which affects the polymerization parameters is added to the polymerization solution. The block B is then polymerized by adding the dienes b). Prior to or during the addition of the diene it is advisable to dilute the reaction mixture with an inert solvent, in order to ensure sufficient mixing and heat dissipation. The polymerization temperature for the block B is preferably from 50 to 90xc2x0 C., and when using polar, aprotic solvents as randomizer it is particularly preferably from 50 to 70xc2x0 C.
The resultant A-B block copolymers may be terminated by chain terminators or coupling agents or, in the case of bifunctional coupling agents, linked to give linear three-block copolymers, or in the case of higher-functionality coupling agents, linked to give star-shaped block copolymers.
The process is not restricted to solution polymerization. For example, the process can also readily be applied to dispersion polymerization. For this, it is advantageous to use a dispersion medium which is inert toward the anionic polymerization initiators and in which the A block is insoluble, for example, propane, butane, isobutane, pentane or its branched isomers, hexane, heptane, octane or isooctane. In order to obtain a small particle size, from 0.1 to 2% by weight of a dispersing agent is generally added. Examples of suitable dispersing agents are styrene-butadiene two-block copolymers with the highest possible molar mass, for example above 100 000 g/mol.
Other suitable components F) are thermoplastic elastomers such as styrene-butadiene-styrene, for example as described in WO-A 97/40079 (BASF) and Styroflex(copyright) BX 6105 from BASF. Conventional amounts of additives or processing aids, or mixtures of these, may be added to the thermoplastic molding compositions of the invention.
Examples of these are nucleating agents, such as salts of carboxylic, organic sulfonic, or phosphoric acids, preferably sodium benzoic, aluminum tris(p-tert-butylbenzoate), aluminum trisbenzoate, aluminum tris(p-carboxymethylbenzoate), and aluminum triscaproate; antioxidants, such as phenolic antioxidants, phosphites or phosphonites, in particular trisnonylphenyl phosphite; stabilizers, such as sterically hindered phenols and hydroquinones. Use may also be made of lubricants, mold-release agents, dyes, pigments and plasticizers.
Organophosphorus compounds, such as phosphates or phosphine oxides, may be used as flame retardants.
Examples of phosphine oxides are triphenylphosphine oxide, tritolylphosphine oxide, trisnonylphenylphosphine oxide, tricyclohexylphosphine oxide, tris(n-butyl)phosphine oxide, tris(n-hexyl)phosphine oxide, tris(n-octyl)phosphine oxide, tris(cyanoethyl)phosphine oxide, benzylbis(cyclohexyl)phosphine oxide, benzylbisphenylphosphine oxide, and phenylbis(n-hexyl)phosphine oxide. Particular preference is given to the use of triphenylphosphine oxide, tricyclohexylphosphine oxide, tris(n-octyl)phosphine oxide or tris(cyanoethyl)phosphine oxide.
Phosphates which may be used are especially alkyl- and aryl-substituted phosphates. Examples of these are phenyl bisdodecyl phosphate, phenyl bisneopentyl phosphate, phenyl ethyl hydrogenphosphate, phenyl bis(3,5,5-trimethylhexyl) phosphate, ethyl diphenyl phosphate, bis(2-ethylhexyl) p-tolyl-phosphate, tritolyl phosphate, trixylyl phosphate, trimesityl phosphate, bis(2-ethylhexyl) phenyl phosphate, tris(nonylphenyl) phosphate, bis(dodecyl) p-(tolyl) phosphate, tricresyl phosphate, triphenyl phosphate, dibutyl phenyl phosphate, p-tolyl bis(2,5,5-trimethylhexyl) phosphate, and 2-ethylhexyl diphenyl phosphate. Particularly suitable phosphorus compounds are those where each R is aryl. Very particularly suitable compounds here are triphenyl phosphate, trixylyl phosphate and trimesityl phosphate. It is also possible to use cyclic phosphates. Among these, diphenyl pentaerythritol diphosphate is particularly suitable. Preference is also given to resorcinol diphosphate.
It is also possible to use mixtures of various phosphorus compounds.
The thermoplastic molding compositions of the invention may be obtained by mixing the individual components, generally at from 270 to 330xc2x0 C. in conventional mixing equipment, such as kneaders, Banbury mixers or single-screw extruders, preferably using a twin-screw extruder. To obtain maximum homogeneity in the molding composition, intensive mixing is needed. The sequence in which the components are blended may be varied, for example two or, if desired, more components may be premixed, but it is also possible for all of the components to be mixed together.
The total of components A) to G) is 100%.
The thermoplastic molding compositions of the invention may also generally be blended as described above with other polymers, such as atactic or isotactic homopolystyrene, or with styrene copolymers with comonomers such as acrylonitrile, methacrylates and/or diphenylethylene, or with polyamides, polyesters or polyphenylene ethers, or mixtures of the polymers.
The thermoplastic molding compositions of the invention have high impact strength, high stiffness and good flowability (processability). They are suitable for producing fibers, films or moldings.

Impact resistant thermoplastic molding materials comprised of syndiotactic polystyrene, glass fibers and acrylate impact modifiers

Abstract: G) additives,


Systems and methods are disclosed which facilitate the management of changes to a hosted network. In one aspect, a resource optimization manager obtains an identification of one or more changes to be implemented on a hosted network. The network validation manager component simulates the implementation of the identified changes and records state information associated with the monitored simulation. The network validation manager component generates a network change template that includes the information recorded from the simulation of the change to the hosted network. In another aspect, the network validation manager component can utilize network change templates to monitor the implementation of changes to the hosted network. The network change templates can then be utilized to determine whether to proceed with implementation of the change to the hosted network or whether to revert the hosted network to a condition prior to the implementation of the identified change.

Generally described, computing devices utilize a communication network, or a series of communication networks, to exchange data. Companies and organizations operate computer networks that interconnect a number of computing devices to support operations or provide services to third parties. The computing systems can be located in a single geographic location or located in multiple, distinct geographic locations (e.g., interconnected via private or public communication networks). Specifically, data centers or data processing centers, herein generally referred to as a "data center," may include a number of interconnected computing systems to provide computing resources to users of the data center. The data centers may be private data centers operated on behalf of an organization or public data centers operated on behalf, or for the benefit of, the general public.
In operation, a data center may need to configure, update, or modify components of an active network. For example, a data center may need to modify routing information utilized by one or more components or make modifications to the network topology. For purposes of scaling, however, data centers often would like to utilize automated tools to implement the configurations, updates, or modifications. However, such automated tools typically do not have an ability to monitor and assess state information associated with components of a hosted network, often referred to as the health of the network.

Managing networks utilizing network simulation


A vacuum device according to the present invention may comprise: a vacuum unit for suctioning air from inside a packaging back through a check valve of the packaging back, thereby generating a vacuum therein; and a clamping unit provided on the vacuum unit so as to clamp the packaging back such that the check valve of the packaging back airtightly communicates with an air suction portion of the vacuum unit.

Vacuum devices for removing air from a packing bag to which food or articles are introduced, to reduce a volume of food or articles to pack the same in order to prevent oxidation and deterioration of food or cooked food and store the same for a long period of time have been developed and used.
For reference, a packing bag may have a check valve such as a vacuum valve of Korean Patent Application No. 2010-0057083, which is configured to allow air to be released externally from the packing bag and prevent an introduction of air, and such a packing bag may be a zipper bag having a zipper formed along the edge of one end as illustrated in FIGS. 3 and 4.
However, air suction may not be easily performed during a process of evacuating the inside of a packing bag by the vacuum device.
The reason is because, during the process of sucking air from inside the packing bag with the vacuum device, an air suction part of the vacuum device and the check valve of the packing bag are not in airtight communication with each other each other, forming a gap between the air suction part and the check valve to allow ambient air to be sacked into the vacuum device.
That is, in the process of bringing the check valve of the packing bag into contact with the air suction part of the vacuum device, the packing bag may not be in close contact with the air suction part, that is, the packing bag, while in a corrugated state, may be brought into contact with the air suction part, or while the packing bag may be in close contact with the air suction part, the corresponding state may not be continuously held during a vacuum suction process and a slightly separated state may occur, causing ambient air to be introduced to the inside of the packing bag through a gap not in close contact, and thus, the packing bag cannot be smoothly evacuated within a short time.


The present disclosure is directed toward systems and methods for managing commerce related groups and communications within a social networking system. For example, systems and methods described herein can identify characteristics of social networking system groups and posts, and determine, based on the identified characteristics, whether the social networking system groups and posts are for-sale groups and sale listings, respectively.

1. Technical Field
One or more embodiments of the present disclosure relate generally to commerce within a social networking system. More specifically, one or more embodiments of the present disclosure relate to managing commerce related groups and communications within a social networking system.
2. Background and Relevant Art
While formal commercial settings are commonly utilized for the purchase of goods, people also buy and sell goods in informal commercial settings. For example, garage sales, yard sales, and estate sales provide a setting where individuals can negotiate the sale and purchase of a wide range of goods. These informal commercial settings embody the notion that "one man's trash is another man's treasure," and provide individuals with ways to sell things they no longer want, or purchase things they need for less than they would typically spend in a formal commercial setting.
It is not surprising that the garage sale format of buying and selling goods has transitioned online via social networking systems. A social networking system generally allows for the formation of forum-like groups dedicated to a singular purpose. Social networking system users can join a social networking system group to participate in discussions, ask questions, post articles, etc. A social networking system "for-sale" group typically functions like a neighborhood garage sale and allows users to submit sale listings that advertise goods they would like to buy or sell. Users can utilize the functionality of the social networking system to inquire after a particular item they would like to buy, or sell a particular item that they no longer need.
Additionally, users can also buy and sell items via their own personal newsfeeds within a social networking system. For example, a user's personal newsfeed can include social networking system posts from the user's social networking system "friends" or co-users. Thus, a user can create a social networking system post or "sale listing" advertising an item for sale. Once the user creates the sale listing, the user can submit the sale listing to the social networking system for distribution via the newsfeeds of the user's friends.
Problems arise, however, due to the fact that a social networking system generally does not specifically classify a particular social networking system group as a for-sale group. For example, even though the social networking system may host a particular group where members buy and sell various goods, the social networking system generally has no mechanism to classify that particular group in a different manner from other social networking system groups that have no commercial intent. Accordingly, because the particular group is not appropriately classified as a for-sale group, the social networking system may fail to include the particular group in relevant search results, or may fail to suggest membership in the particular group to a social networking system user who would benefit from knowing that the particular group exists.
Similarly, further problems arise in light of the fact that a social networking system generally does not specifically classify a social networking system post as a sale listing. For example, a social networking system user may compose a social networking system post for the purpose of advertising a particular item that the user would like to sell (e.g., a sale listing). However, because the social networking system has no specific classification for sale listings, the social networking system may not include the user's post in relevant searches. Furthermore, the social networking system may not submit the user's post to newsfeeds and groups where the post will have the greatest advantage.
Thus, there are several disadvantages to current methods for managing commerce related groups and communications within a social networking system.

Managing commerce groups and posts in a social networking system


A harvester head reel may include a bat support and an extendable bat supported by the bat support. The extendable bat may have a first segment and a second segment overlapping the first segment. The harvester head reels may further include a first finger extending from the first segment and a second finger extending from the second segment.

Harvesters are utilized to gather and harvest a crop. Such harvesters may include a head which separates the crop from the underlying growing medium and feeds the crop into the harvester. Depending upon the crop being harvested, such heads may include a reel having a hub which supports multiple angularly spaced bats that carry tines or fingers. The reel is rotated such that the fingers carried by the bats engage and gather the crop being harvested.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements. The figures are not necessarily to scale, and the size of some parts may be exaggerated to more clearly illustrate the example shown. Moreover, the drawings provide examples and/or implementations consistent with the description; however, the description is not limited to the examples and/or implementations provided in the drawings.


A frequency tracking circuit and method comprising a master crystal oscillator circuit is used for frequency tracking between a handset and a base station comprising a calibration subsystem for taking a temperature measurement, a reference control circuit for determining a numerical value needed to align a handset frequency with a base station frequency, an adder for adding the numerical value to a previous numerical value determined by the reference control circuit, a latch for latching the output of the adder, and a low precision master crystal oscillator for clocking the frequency of the latch. The most significant bit from the latch is input into a phase/frequency detector for forcing a voltage controlled oscillator to track a desired frequency.

1. Field of the Invention
This invention relates generally to producing an accurate desired output frequency and channel spacing while using crystals with much lower tolerance requirements than normally required and no xe2x80x9cpullabilityxe2x80x9d requirement. More particularly, it relates to a system and method for producing an accurate desired output frequency and channel spacing using a numerically controlled oscillator (xe2x80x9cNCOxe2x80x9d) instead of a conventional integer reference divider to generate a reference frequency used in a frequency synthesizer.
2. Background of Related Art
Cordless telephone, cellular, and wireless local area network (xe2x80x9cLANxe2x80x9d) and personal area network (xe2x80x9cPANxe2x80x9d) and user terminals generally employ frequency synthesizers to generate signals, including transmitter output signals, local oscillators, etc. Each user terminal""s synthesizer generates these frequencies based on a local master oscillator, invariably a crystal oscillator. Such crystal oscillators have finite tolerances.
A typical way to synchronize two communicating units has been to make one of the units a timing slave to the other unit. In a digital cordless telephone, for example, a base station may serve as a timing master and a handset may serve as a timing slave. In such an arrangement, the receive timing of the handset may be derived from the base station transmission timing via a signal received by the handset from the base station. The transmit timing of the hand unit may then be derived, for example, from the receive timing as is typical. In this manner, synchronization of the timing among the base station and the handset is achieved.
A typical arrangement for achieving synchronization according to this typical synchronization scheme employs a phase lock loop in the slave unit, presumed herein to be the handset (for purposes of discussion only, and not intended to be limited to that case). The phase lock loop serves to lock on the signal received by the handset and to recover a timing signal, i.e., a clock signal, from that received signal. The received signal itself is then utilized by the handset to dictate the handset timing. In this configuration, transmit timing of the handset is derived directly from the receive timing, and the phase lock loop is employed to compensate for jitter of the received signal and to lock on that signal in order to derive transmit timing. When the received signal so dictates timing of the handset, the handset acts as a timing slave to the base station, thereby resulting in synchronization.
The frequencies generated by user terminals and base/master stations must align accurately for proper system operation and to avoid undue interference to users of adjacent channels. These factors generally result in the necessity to use relatively high precision (and therefore relatively expensive) crystal oscillators in both the user terminals and the base/master stations.
Some current cordless telephone systems use a varactor diode to adjust a frequency of a handset""s master oscillator, in combination with a processor-based software algorithm, driven by an estimate or measurement of a frequency offset between a handset and its companion base station, to control a digital-to-analog converter (DAC). The DAC""s output is used as a control voltage to the varactor diode to align the handset""s master oscillator with that of a companion base station.
A disadvantage of using a varactor diode is that it is frequently an additional external component, along with additional associated passive components, on a printed circuit board (xe2x80x9cPCBxe2x80x9d), taking up valuable PCB area and adding cost. External varactor diode circuits also subject the master oscillator to a certain degree of vulnerability to external noise modulation of the varactor diode, thus degrading the spectral purity of the handset""s master oscillator. Careful design and layout can minimize this latter disadvantage, but the risk still exists, sometimes requiring additional shielding and filtering which further consume PCB area and adds cost.
Additionally, the crystal employed in the handset""s master oscillator must be specified for a specific degree of xe2x80x9cpullabilityxe2x80x9d, which adds to the cost and can result in the necessity of employing larger crystal packages than would otherwise be necessary, were it not for the xe2x80x9cpullabilityxe2x80x9d requirement.
FIG. 1 illustrates a conventional circuit utilizing a master crystal oscillator circuit 1 connected to one side of a phase/frequency detector 2. A second input to the phase/frequency detector 2 is produced by the output of modulus control logic 3. A dual modulus prescaler 4 feeds the modulus control logic 3 and receives a signal from the modulus control logic 3. A voltage controlled oscillator 5 outputs to the dual modulus prescaler 4 and receives a filtered control voltage, filtered by low pass filter 6, from the phase/frequency detector 2.
In operation, master crystal oscillator circuit 1 produces a square-wave Fref that is applied to a first input of phase/frequency detector 2. The phase/frequency detector 2 produces a voltage based on the difference between the square-wave produced by master crystal oscillator circuit 1 and the frequency of the signal produced by modulus control logic 3. Phase/frequency detector 2 produces a control voltage that is output to VCO 5. The control voltage contains a ripple component at Fref that causes undesirable sidebands at the VCO 5 output frequency +xe2x88x92Fref. Low pass filter 6 removes the ripple components, suppressing these xe2x80x9creference spurs,xe2x80x9d dampens transient responses, such as when changing frequencies, and is used to optimize settling time and other loop parameters. One output from VCO 5 is output to a dual modulus prescaler 4, which alternately divides the frequency produced by VCO 5 by either a P or P+1 value.
Modulus control logic 3 is controlled by two values A and N, where A is always smaller than N. A and N are programmable counters that decrement simultaneously to their terminal counts and are decoded in the modulus control logic to control the dual modulus prescaler""s 4 value to be either P or P+1. A represents the number of cycles of the VCO output for which the dual modulus prescaler 4 divides by P+1. N represents the number of additional cycles of the VCO output (after counter A has decremented to its terminal count) that dual modulus prescaler 4 divides by P. A modulus control signal from the modulus control logic block 3 feeds back to the dual modulus prescaler 4 to change its divisor from P+1 to P, and vise versa, according to the state of the divide-by-A and divide-by-N counters. The output of the A counter in the modulus control logic block 3 is the VCO signal divided to Fref, which is applied to the phase/frequency detector 2. In this manner, the control voltage produced by the phase/frequency detector 2 forces the VCO 5 to converge onto a desired frequency.
FIG. 2 illustrates a conventional master crystal oscillator circuit using a digital-to-analog converter 7 connected to a varactor 8. The varactor 8 outputs a control signal to varactor that controls master crystal oscillator 9, whose output is thereafter divided by the xe2x80x9creference dividerxe2x80x9d 10 to create a reference frequency for a frequency synthesizer.
In operation, the DAC 7 produces a control voltage for varactor 8 based on a software algorithm. The software algorithm can be adjusted during the manufacturing phase of the circuit to compensate for individualistic characteristics of the master crystal oscillator 9. Varactor 8, based on the control voltage produced by DAC 7, adjusts the frequency produced by the master crystal oscillator 9.
The frequency produced by the master crystal oscillator 9 is divided by the divider 10 by a value R. R is typically the channel spacing between the different possible channels available for transmission and reception. A square-wave reference frequency Fref is output from the divider 10 to the phase/frequency detector 2 in FIG. 1.
FIG. 3 illustrates a second conventional master crystal oscillator circuit using a master crystal oscillator 13 connected to an initial calibration adjustment circuit 11, a temperature compensation circuit 12 and a divider 14.
In operation, the initial calibration adjustment circuit 11 is set or programmed during manufacture of the master crystal oscillator circuit to set the master crystal oscillator to operate on the desired frequency at some nominal temperature.
Temperature compensation circuit 12 may be comprised in a variety of ways from a variety of components such as a varistor/resistor bridge or other termperature sensing device, a micro controller, nonvolatile memory, a digital-to-analog converter, a varactor, etc. The temperature compensation circuit 12 changes the varactor control voltage value according to variations in temperature to produce a constant output frequency. The varactor performs as the varactor in FIG. 2, wherein the varactor xe2x80x9cpullsxe2x80x9d the frequency of the master crystal oscillator 13 to adjust the frequency produced by the master crystal oscillator 13.
The frequency signal produced by the master crystal oscillator 13 is divided by divider 14 by a value R. R is typically the channel spacing between the different possible channels available for transmission and reception. The resulting square-wave reference frequency Fref is output from the divider 14 to the phase/frequency detector 2 in FIG. 1.
It should be noted that in some implementations it is possible to combine the initial calibration circuit and the temperature compensation circuit into a single dual-purpose circuit that serves both purposes.
There exists a need for an apparatus and method that offers a higher level of integration and does not rely on expensive high accuracy crystals. There exists a need for crystals with a specified xe2x80x9cpullabilityxe2x80x9d combined with relatively complex circuits, and a varactor and associated circuitry for the generation of an accurate desired output frequency and channel spacing in user terminals which align appropriately with the frequencies and channel spacings of a companion base/master station
In accordance with the principles of the present invention, a 1-bit (square wave) output numerically controlled oscillator (NCO) is used instead of a conventional divide by R divider to generate a reference frequency Fref for a frequency synthesizer. A low precision master crystal oscillator clocks the NCO, with a phase increment value, REFCTL, being added to a previously-stored value fed back from the output of a latch at each xe2x80x9ctickxe2x80x9d of the master crystal oscillator clock. The frequency of the master oscillator and the value of the phase increment value, REFCTL, determine the value of Fref. The most significant bit from the latch is a square wave signal at Fref that is input into a phase/frequency detector and loop filter arrangement to force a voltage controlled oscillator to track a desired frequency in an otherwise conventional manner.
A master crystal oscillator circuit in accordance with another aspect of the present invention comprises a master crystal oscillator circuit that compensates for variations in temperature to produce a stable Fref over a wide range of temperature variations. A calibration subsystem takes temperature measurements that are monitored by a controller element that in turn employs that value to access a particular memory location in a non-volatile memory array containing the correct phase increment value for each of a multiplicity of temperatures to constantly produce the correct value of Fref as temperature varies. The values in the non-volatile memory array are programmed during the manufacture of the master crystal oscillator circuit by cycling the circuit over the desired range of temperatures, determining, for each temperature, the phase increment value necessary to compensate for the frequency variation with temperature of that individual master crystal oscillator circuit""s crystal at that temperature, and storing that phase increment value into the memory location corresponding to that particular temperature.
A master crystal oscillator circuit in accordance with another aspect of the present invention comprises a master crystal oscillator circuit that allows the frequency synthesizer in a first node of a communications system (e.g., a handset in a cordless telephone system, a handset in a telephone system, or a wireless LAN terminal) to accurately track the frequency of a second node in the system. The first node communicates with the second node (e.g., a cordless telephone or cellular telephone base station, or the access point or another terminal in a wireless LAN system), and as the frequency of the second node may vary, communication is maintained while allowing the use of a low precision crystal in the first node.

Method of temperature calibrating a numerically controlled oscillator using low tolerance master crystals


A method for fabricating a bottom electrode structure for a semiconductor capacitor. The method according to the present invention includes providing an interlayer insulating layer having a conductive plug formed therein. A first bottom electrode layer is formed on the interlayer insulating layer. An oxygen diffusion barrier layer is formed on the first bottom electrode layer. A second bottom electrode layer is formed on the first oxygen diffusion barrier layer. Thereafter, portions of the second bottom electrode layer, first oxygen diffusion barrier layer, and first bottom electrode layer are selectively removed to form a bottom electrode pattern. A third bottom electrode is formed on sidewalls of the bottom electrode pattern.

1. Field of the Invention
The present invention relates to a memory device with a high device packing density, and more particularly, a semiconductor device including a capacitor with an improved bottom electrode and a method for fabricating the same.
2. Description of Related Art
In general, a semiconductor memory device is provided with a driving transistor and a capacitor which stores information therein. A volatile memory device, such as a dynamic random access memory (DRAM), stores information as an amount of charge in the capacitor. The amount of charge stored in the memory device, such as a DRAM, can be increased as follows: fabricating a three dimensional capacitor to increase an effective area of the capacitor; reducing a thickness of a dielectric in the capacitor; and using a dielectric having a higher dielectric constant.
Because increasing the stored charge by increasing the surface area and reducing the thickness of the dielectric requires complicated fabrication process steps, these techniques for increasing the stored charge are not generally adopted. Instead, the stored charge is increased by using high dielectric constant dielectric films. As the high dielectric constant dielectric films, (Ba, Sr)TiO.sub.3 and (Pb, La)(Zr,Ti)O.sub.3 may be used. The high dielectric constant dielectric films BST[(Ba, Sr)TiO.sub.3 ] are mostly used in DRAMs, and the high dielectric constant dielectric films PZT(PbZrTiO.sub.3) are mostly used in flash random access memories (FRAMs). If a high dielectric constant dielectric film such as BST is deposited on a silicon substrate directly, the silicon oxidizes making a defective contact or the BST film degrades due to a reaction between BST and Si. Because of this, when high dielectric constant dielectric films such as BST are used as the dielectric of a capacitor, a metal film such as Pt, Ru and Ir, which is less reactive, is usually used as the bottom electrode of the capacitor. This is applicable to both DRAMs and FRAMs. Because a complicated three dimensional electrode is not required for increasing an effective area of the capacitor if a high dielectric constant dielectric film such as BST or PZT is used, a memory device having a device packing density greater than the giga class can be fabricated according to the simple structure shown in FIG. 1.
As shown in FIG. 1, an interlayer insulation layer 2 is formed on a substrate 1, and has a contact hole formed therein. A plug 3 fills the contact hole, and a barrier 4 is formed on the substrate 1 and the plug 3. A bottom electrode 5 is formed on the barrier 4, and a dielectric 6 covers the interlayer insulation layer 2, the bottom electrode 5 and the barrier layer 4. A top electrode (not shown) is then formed on the dielectric 6.
When PZT or BST is used as the dielectric film 6, one of Pt, Ru and Ir is used as the bottom electrode 5. However, when Pt or Ru is used as the bottom electrode 5, the electrical characteristics of the capacitor change.
FIGS. 2A and 2B illustrates the use of Pt as the bottom electrode 5. Pt has a great work function, which results in excellent electrical characteristics and reduced leakage current, but Pt is oxygen permeable. As a result, oxidation at the barrier 4 and plug 3 interface takes place to form an oxide layer 7. Typically this oxidation consumes the barrier 4. The oxygen diffuses mostly along the Pt grain boundaries during the formation of the dielectric 6 causing oxygen holes in the dielectric 6, which degrades the electrical characteristics thereof. As shown in FIG. 2B, residue 8 from an etching process inhibits patterning.
FIG. 3 illustrates the use of Ru as the bottom electrode 5. When the dielectric film 6 is deposited, oxygen is absorbed from the dielectric 6 by the bottom electrode 5 as the bottom electrode 5 oxidizes. This forms an oxygen depletion layer between the dielectric 6 and the bottom electrode 5 resulting in poor electrical performance. To prevent this, the bottom electrode 5 is usually oxidized prior to deposition of the dielectric 6 so that the oxide layer formed therein prevents further oxidation using the oxygen in the dielectric 6. Typically, the Ru bottom electrode 5 is formed through etching with oxygen to form an oxide layer 9, RuOx, at the surface of the Ru bottom electrode 5 as shown in FIG. 3. Besides preventing the absorption of oxygen from the dielectric 6, the oxide of Ru is conductive. But the oxide of Ru also forms a rugged deposition surface as shown in FIG. 2B. Because of this rugged surface, the oxide layer 9 has poor electrical characteristics.

Method for fabricating semiconductor device including capacitor with improved bottom electrode

Hyundai Electronics Industries Co., Ltd.


A Data Storage Device (DSD) includes a first memory for storing data and a Storage Class Memory (SCM) for storing data. The SCM has at least one characteristic of being faster than the first memory in storing data, using less power to store data than the first memory, and providing a greater usable life than the first memory for repeatedly storing data in a same memory location. At least a portion of the SCM is allocated or reserved for use by a host, and logical addresses assigned to the SCM are mapped to device addresses of the first memory identifying locations for storing data in the first memory. The host is provided with an indication of the logical addresses assigned to the SCM to allow the host to retrieve data from and store data in the DSD or to directly access data using the logical addresses assigned to the SCM.

Data Storage Devices (DSDs) are often used to record data onto or to reproduce data from a storage media such as a rotating magnetic disk or a solid-state memory. New types of storage media, referred to as Storage Class Media (SCM), can provide various benefits over more conventional storage media, such as a rotating magnetic disk or flash memory. SCM can include, for example, a Magnetoresistive Random Access Memory (MRAM), a Phase Change Memory (PCM), a Resistive RAM (RRAM), Ferroelectric RAM (FeRAM), Programmable Metallization Cell RAM (PMC-RAM), Chalcogenide RAM (C-RAM), Ovonic Unified Memory (OUM), or a 3D XPoint memory.
Some DSDs may include different types of storage media in the same DSD, with each type of storage media having different advantages or disadvantages. SCM is typically faster than conventional storage media in storing data, may use less power, or provide a longer usable life for storing data. However, the amount of SCM storage space may be limited, since SCM generally costs more than conventional storage media.

This patent is subject to a terminal disclaimer.

Tiered storage using storage class memory


An optical signal transmitter includes: first outer modulator to generate first modulated optical signal, the first outer modulator including a pair of optical paths and a first phase shifter to give phase difference to the pair of optical paths; second outer modulator to generate second modulated optical signal, the second outer modulator including a pair of optical paths and a second phase shifter to give phase difference to the pair of optical paths; combiner to generate polarization multiplexed optical signal by combining the first and second modulated optical signals; phase controller to control the phase difference by the first phase shifter to A−Δφ and control the phase difference by the second phase shifter to A+Δφ; and power controller to control at least one of the first and second outer modulators based on AC component of the polarization multiplexed optical signal.

The needs for super high speed transmission systems with a speed of more than 40 Gbit/s (for example, 100 Gbit/s) have been increasing rapidly. For this reason, development is under way for practical realization of an optical transmission system that adopts a multilevel modulation scheme applied to a radio system (for example, the QPSK modulation using four-level phase modulation). However, as the transmission-signal speed becomes higher, solving problems related to the feasibility of the electric signal circuit and problems related to the degradation of the optical transmission signal (transmission-signal spectrum degradation due to an optical filter and signal degradation due to chromatic dispersion and accumulation of optical noises) becomes more difficult.
As one of techniques for solving these problems, optical polarization multiplexing has attracted attention. A polarization multiplexed optical signal is generated by, for example, an optical signal transmitter illustrated in FIG. 1A. The optical signal transmitter has a light source (LD), a pair of modulators, and a polarization beam combiner (PBC). Continuous wave light output from the light source is spilt and guided to the pair of modulators. The pair of modulators modulate the continuous wave light respectively with corresponding data signal, and generate a pair of modulated optical signals. The polarization beam combiner generates a polarization multiplexed optical signal illustrated in FIG. 1B by combining the pair of modulated optical signals. In other words, in the polarization multiplexing, two data streams are transmitted using two polarized waves (X polarization and Y polarization) that have the same wavelength and are orthogonal to each other.
Accordingly, in the polarization multiplexing, the data speed becomes half, realizing the improvement of the characteristics of the electric-signal generation circuit and reduces the cost, size and power consumption of the circuit. In addition, the characteristics of the optical transmission system as a whole is improved, as influences from quality-degradation factors such as dispersion on the optical transmission path are reduced. Japanese Laid-open Patent Publication No. 62-24731, Japanese Laid-open Patent Publication No. 2002-344426, Japanese Laid-open Patent Publication No. 2008-172799 describe a transmission system using the polarization multiplexing. In addition, as related arts, configurations described in Japanese Laid-open Patent Publication No. 2009-63835 and Japanese Laid-open Patent Publication No. 2008-172714 have been proposed.
However, in an optical signal transmitter that generates a polarization multiplexed optical signal, a modulator is provided for each polarization as illustrated in FIG. 1A. For this reason, differences in the optical power may be generated between the polarization in the polarization multiplexed output signal, due to factors such as manufacturing variability of characteristics between the modulators (for example, loss of the LN modulator) and characteristics of the optical splitter and/or the optical combiner.

Method for controlling polarization multiplexed optical signal


When position information is added in a real-time fashion, anonymity of movement trajectories is ensured and the degree of abstraction of positioning data included in the position information is prevented from becoming too high. A group of anonymous information with a second positioning time preceding a first positioning time is partitioned into two or more groups so that the anonymous information with the first positioning time satisfies a predetermined anonymity metric and so that a degree of abstraction of the abstracted positioning data in the anonymous information becomes lower than a predetermined standard value, anonymous information including positioning data with the first positioning time abstracted by the partitioned groups is generated, and the generated anonymous information is stored in an anonymous information storage unit in association with the anonymous information with the second positioning time.

The present invention relates to an information protection device and an information protection method.
In recent years, the use of position information including positioning data acquired by a GPS (Global Positioning System) or wireless LAN (Local Area Network) installed in a portable terminal or an automobile has increased for a variety of applications. Furthermore, the number of services for periodically acquiring position information and recording the movement trajectory or action history of the users of portable terminals or automobiles has been growing.
In addition to the information that can identify the user, such as one's home, place of employment, and school, the position information may include information that the user does not want to be known to others, such as a hobby or hospital. Therefore, the position information has a high degree of privacy. Further, the movement trajectory, which is the time-series information of position information, may also represent the route to a sensitive location with a high degree of individual privacy and the presence or absence at such a location, and can identify the user at a level higher than independent position information. In addition, where the movement trajectory is used in a real-time fashion by a service provider or data analyst, the user is always under a threat of being tracked and monitored. Therefore, the movement trajectory is privacy information with a very high degree of privacy. Accordingly, when such privacy information is provided to the service provider or data analyst, anonymity should be ensured by anonymization.
The anonymization, as referred to herein, is the processing by which privacy information is processed so the user could not be identified. A metric indicating the degree to which the user cannot be identified is called anonymity metric. Thus, k-anonymity is well known as the anonymity metric which is presently used. Information which is included in the privacy information and is not an identifier that can uniquely identify the user, but can identify the user when background information or the like is taken into account, is called quasi-identifier (indirect identifier). Further, information that the user does not want to be known to others is called sensitive information. The k-anonymity is the metric that indicates the presence of k or more types of sensitive information having the same quasi-identifier by anonymization of the quasi-identifier. By ensuring k-anonymity, it is possible to reduce the possibility of identifying the user to 1/k or less, thereby making it difficult to identify the user.
A patient's medical record such as shown in FIG. 13 will be considered below by way of example. The medical record shown in FIG. 13 includes the name, gender, occupation, and age of the patient together with the medical condition. The medical condition is sensitive information with a high degree of privacy. The name is an identifier uniquely identifying the person, and the gender, occupation, and age are quasi-identifiers that can identify the person. For example, even if the patient's name is unknown, the patient can be estimated on the basis of a combination of occupation and age. In other words, even in a state in which the patient's name is hidden, a person knowing the patient's occupation and age can know the medical condition of the patient. In order to avoid this, the level of abstraction of occupation and age can be increased, as shown in FIG. 14. FIG. 14 presents anonymous information obtained by anonymization of the medical record shown in FIG. 13, such as to ensure the k anonymity of k=2. In the anonymous information shown in FIG. 14, even if the occupation and age are known, two or more medical conditions are present for all combinations of occupation and age. As a result, even a person knowing the occupation and age of a patient, cannot accurately estimate the patient's medical condition. Further, l-diversity, t-closeness, and m-invariance are known in addition to k-anonymity as metrics of anonymity.
Non-Patent Document 1: O. Abul, F. Bonchi, M. Nanni "Never Walk Alone: Uncertainty for Anonymity in Moving Objects Databases", Proceedings of the 24th International Conference on Data Engineering, IEEE, April 2008, p. 376-385.
However, position information and movement trajectory are different in nature from the above-described information. Positioning data of position information point to a specific location. In some cases, the positioning data indicate a location with a high degree of privacy for everyone, but privacy of specific positioning data generally differs depending on the user linked thereto. Even if the positioning data indicate the location, such as a hospital or home, the meaning of the location is difficult to estimate by merely linking the user and the positioning data. Meanwhile, information such as the staying time duration and the length thereof can be obtained from continuous positioning data such as a movement trajectory. From such information, it is possible to estimate the meaning of the location indicated by the positioning data. Then, it is possible to identify the user on the basis of the estimated information. Therefore, the positioning data constituting the movement trajectory can be considered as a quasi-identifier and also as sensitive information.
FIG. 15 shows the information obtained by subjecting position information to k-anonymization. Each point represents positioning data of position information, and the ellipse is the anonymous information obtained by anonymization of position information by abstraction of positioning data of position information enclosed in the ellipse. In FIG. 15, k-anonymity with k=4 is ensured and accurate position of the user is unknown.
In addition to the above-described specific feature of position information, the movement trajectory has a specific feature of representing the actual conditions of the user's life. By linking the user with the movement trajectory, it is possible to reveal all destinations and staying locations including the location with a high degree of privacy for the user. There is also a risk of the user's movement being monitored or tracked. Therefore, the privacy of movement trajectory is much higher than that of the independent position information or a combination of a plurality of types of simple position information. Furthermore, in some cases the user can be identified only by revealing several types of positioning data of position information in the movement trajectory. For example, information such own home, place of employment, and the nearest station are often known to friends and colleagues. Therefore, where the positioning data on those locations are included in the movement trajectory, the user linked to the movement trajectory can be identified and privacy information on other locations such as hospital and locations clearly indicating preferences can be revealed.
Accordingly, the anonymization of the movement trajectory is performed to make it difficult to link the user with the movement trajectory. In order to ensure k-anonymity, it is necessary to generate the movement trajectory that is anonymized so as to include k or more movement trajectories. FIG. 16 shows an example of movement trajectory anonymization. In FIG. 16, a tubular movement trajectory is generated such that includes four movement trajectories. The information in which the correspondence of the movement trajectory and the user is thus obscured is called anonymous information. The objective movement trajectory is included in the anonymous information in the entire zone from the start point to the end point of the movement trajectory. Therefore, position information within a specific period of time in the anonymous information also satisfies the k-anonymity at all times. In other words, the anonymous information shown in FIG. 16 satisfies the k-anonymity (k=4).
Non-Patent Document 1 discloses an example of anonymization technique using anonymous information. Non-Patent Document 1 describes the technique for anonymization of accumulated movement trajectories and suggests the anonymization technique which uses the anonymity metric of (k, δ)-anonymity and by which static movement trajectories accumulated in the database are generalized into a tubular shape. With such a technique, the anonymization is performed by grouping and abstracting data with clear start points and end points of movement trajectories for which distances between the movement trajectories are close to each other. Ensuring the k-anonymity with respect to static movement trajectories means ensuring that k or more movement trajectories consistently present between the start point and the end point are included in the same group (anonymous information). As a result, even if there is one known staying point in the user's movement trajectory, the movement trajectory itself cannot be identified. The assembly of movement trajectories is abstracted into a tubular shape in a three-dimensional space of latitude, longitude, and time at which they are measured, and the abstracted assembly is outputted as anonymous information.
The anonymization technique shown in FIG. 16 is effective for anonymizing movement trajectories within a predetermined period, but is not necessarily effective for real-time anonymization of movement trajectories such that position information is added moment by moment. In such an environment, the movement trajectory extends (enlarges) on a time axis as the unknown position information arrives periodically. Therefore, in order to use the movement trajectory in a real-time fashion, while ensuring anonymity, it is necessary to perform the real-time anonymization with respect to the increments of the movement trajectory. When such anonymization is performed, the anonymization with respect to the increments should be performed after the result of the already performed anonymization has been taken into account. This is done to make it difficult to establish the correspondence between the user and the movement trajectory that depends on a combination of a plurality of pieces of position information, in the same manner as in the anonymization of static movement trajectories. With the anonymization method illustrated by FIG. 16, the anonymization is performed with respect to accumulated movement trajectories, and no anonymization with respect to the increments of the movement trajectory is assumed. In particular, the anonymization method illustrated by FIG. 16 is based on a macroscopic approach according to which the anonymization is performed once so as to satisfy the anonymity requirement in the entire path between the start point and the end point, and is not intended for processing the local position information such as increments of movement trajectory.
Therefore, where the anonymization method illustrated by FIG. 16 is applied to newly arrived increments, it is assumed that the anonymization is performed with respect to a short path for which the increment data and data preceding thereto are captured as the end point and the start point, respectively. In such a case, in order to ensure k-anonymity, it is necessary to configure the anonymous information by using the previously anonymized anonymous information and at least k or more identical movement trajectories.
However, every user acts and moves in his or her individual manner. Therefore, it is unlikely that the users with adjacent movement trajectories at some point in the past will continue following the adjacent trajectories in the same manner in the future. Therefore, it can be assumed that in the anonymization method illustrated by FIG. 16, the geographical similarity between movement trajectories forming anonymous information decreases and the degree of abstraction of anonymous information gradually increases with the passage of time. In other words, where the anonymous information is configured of the same combination of movement trajectories at all times, the positioning data of position information included in the movement trajectories can become too abstract and meaningless information can be obtained. Furthermore, the anonymity cannot be guaranteed in the case where the anonymization is performed independently with respect to movement trajectories in different time intervals, without taking into consideration the movement trajectories that have been anonymized in the past.

Information protection device and information protection method


In alternative embodiments, provided are methods for the glycosylation modification of bioactive compounds and drugs using isolated, recombinant or genetically modified uridine diphosphate glycosyl-transferases (UGTs). In alternative embodiments, provided are methods for modifying UGTs to generate recombinant UGTs with altered donor and/or acceptor specificities. In alternative embodiments, provided are methods for screening for recombinantly engineered UGTs with new or altered properties, for example, for new or altered donor and/or acceptor specificities, where in alternative embodiments the screening comprise use of bacterial, yeast or baculovirus expression system.

Glycosylation is a biological process that improves bioavailability and therefore pharmacological activities. The main implication of glycosylation is in drug discovery. Uridine diphosphate (UDP) glycosyltransferases (UGTs) are key components in the glycosylation process. They can be used for modifying small molecular drugs with various sugars.
A major issue in drug modification and discovery is that it is difficult to perform targeted glycosylation of specific drug scaffolds with current conventional synthetic approaches. Different UGTs have unique sequences and specific templates.
The UGT UGT71G1 is a multifunctional glycosyltransferase and can glycosylate terpenoids such as hederagenin, flavonoids such as quercetin, and SN-38, an active metabolite of the anti-cancer drug CPT-11 (irinotecan). Terpenoids have been proven to benefit human health, where some can fight malaria, some can be used to treat cancer.

Glycosylation modification of bioactive compounds and drugs by plant glycosyltransferases (UGTs)


An implementation is described for navigating media. The implementation includes displaying a portion of the media. The implementation also includes displaying a navigation interface corresponding to the media. The navigation interface includes an active region, a current view region, and a ghost region. The active region corresponds to at least a portion of the media. The current view region corresponds to a portion of the media to be displayed. The current view is at least partially defined by a selector handle. The ghost region is coupled to the active region. The ghost region represents a range of remaining media other than the portion of the media in the active region. The ghost area provides a context for the remaining media relative to the portion of the media corresponding to the active region. The implementation also includes receiving user input to navigate the media according to a visual interaction between the sector handle and the ghost region.

Analysis of images, media, and data is a useful tool in many fields of endeavor. In many instances, the media being viewed may be too large to see all at once. For example, the media may be a large image or long video or audio sequence. Other examples might be a long-time data trend for a stock price or other large sets of data. Conventional solutions, which allow a user to navigate this media, commonly employ sliders or other navigation interfaces. Frequently, it is beneficial or necessary to zoom in on a specific sub-set of the media such as frames in a video or sections of a sound track to get a higher resolution.
FIG. 1 illustrates one embodiment of a conventional navigation interface 10. The illustrated embodiment includes a scale 12, a selector 14, and jump arrows 16. The resolution of the scale 12 corresponds to some density of media. In the illustrated embodiment, the scale 12 corresponds to data between Point A and Point B. The selector 14 corresponds to a portion of the media that is displayed to a user (not shown). The user may drag either side of the selector 14 to vary the amount of the scale 12 that is selected and, hence, the amount of media that is displayed to the user. The jump arrows 16 at either end of the scale 12 are configured to allow the user to scroll through the available media.
However, the illustrated conventional system 10 lacks the ability to present the overall context of the total media when zoomed in to evaluate or analyze the media. For example, when zoomed in on a portion of a video frameset, the context for how that frameset corresponds with the rest of the video sequence is lost. Additionally, in another example, when viewing a portion of a stock price history corresponding to a few weeks, the context of the few weeks relative to the data pertaining to the stock price trend over several years is also lost. Alternatively, if the user zooms out to display the entire set of media, the granularity of the scale 12 decreases. Thus, it is difficult to maintain sufficient granularity of the scale and to view an overall context of the displayed media at the same time.

International Business Machines Corporation


A mill drive system with a transmission arranged beneath a milling table and with at least one planetary and/or spur gear stage as well as a vertical shaft position is provided. In addition, an electric motor is integrated in a housing of the transmission and is connected to a lubricant supply circuit of the transmission. A rotor and a stator of the electric motor have vertically extending axes. Cooling of the motor is performed by a lubricant circulating through the transmission. Furthermore, a lubricating-oil-proof sheath for rotor and/or stator windings of the electric motor for sealing with respect to the lubricant is provided. In addition, the mill drive system includes a converter with a regulation device for backlash-free speed regulation of the electric motor.

Known mill drive systems comprise one or more transmission stages for drive power conversion of an electric motor. The transmission stages and the electric motor in this case form a drive train, which is coupled tightly to a processing process within, for example, a bowl mill, a pug mill, a crusher, a tube mill or a tubular rotary kiln and is subjected to considerable reactions from the processing process. Generally, bevel gear stages are used for linking the electric motor to the drive train.
DE 39 31 116 A1 has described a drive apparatus for a mill with a vertical design, in which a housing of an auxiliary transmission is screwed fixedly to the mill. In this case, a precise alignment of axes, which are far apart from one another, of the drive pinion and the toothed ring is necessary. Furthermore, introducing axial mill forces via an axial thrust bearing into a common transmission housing results in considerable loads for a meshing engagement in the auxiliary transmission. As a result of a common large transmission and mill bearing interior, rapid contamination with lubricating oil for the drive apparatus is favored. In addition, a mechanical torque division in the auxiliary transmission has proven to be problematic in teems of a lack of compensation for excessive constraining forces.
JP 2005 052799 A has disclosed a drive apparatus for a vertical crusher, which is driven either via a toothed ring on a rotatable base plate or via a multi-stage bevel gear transmission. As a result of a lack of adjustment movability at an output stage of the drive apparatus, impact loads are transferred from the processing process into the drive apparatus, in particular into the toothing thereof.
WO 2009/068484 A1 has described a spur gear transmission with one or more transmission stages for driving a machine tool, enclosed by a toothed ring, which spur gear transmission comprises a transmission housing accommodating the transmission stages and a pinion which is capable of an adjustment movement, is arranged on an output shaft of an output stage and meshes with the toothed ring. The transmission housing comprises a first housing part, which is rigid per se and a second rigid housing part. The first housing part surrounds the output stage with the output shaft and the pinion, which is capable of an adjustment movement, and has side walls which protrude beyond the transmission and rest on the pedestal. The second housing part is fastened on the first housing part on an end side without any touching contact with the pedestal.


A detachable accessory carrier for bicycle includes a fixed seat, a positioning member and a fastener. The fixed seat has a positioning portion and a fixing portion communicated mutually. The positioning member has an inserting portion that includes a propping portion corresponding to the fixing portion so that when the inserting portion of the positioning member is assembled to the positioning portion of the fixed seat, the fastener can be coupled with the fixing portion and abut against the propping portion of the positioning member, thereby attaching the detachable accessory carrier reliably to the frame tube of the bicycle. The detachable accessory carrier can be partially detached with only the fixed seat left on the frame tube of the bicycle. The fixed seat has a rim conforming to a periphery of the frame tube so it will not interfere with the cyclist's riding or scrape the cyclist's skin.

1. Technical Field
The present invention relates to bicycle parts, and more particularly, to a detachable accessory carrier for a bicycle, wherein the detachable accessory carrier can be easily attached to and detached from the frame tube of the bicycle.
2. Description of Related Art
Generally, for minimizing unnecessary burdens and thereby maximizing cyclists' performance, BMX (bicycle motocross) bikes are made as brief as possible. As can be seen in the market, BMX bicycles, unlike bicycles made for other purposes, usually have no accessory carriers for carrying accessories such as a water bottle. This is inconvenient for normal riding and limits a BMX bicycle to a single purpose. On the other hand, track bicycles typically come without brakes, so they have to be additionally equipped with a brake set for normal riding.
For attaching additional accessories to such specialized bicycles for facilitating their normal use, it is necessary to provide an accessory carrier that can be easily attached to and detached from a bicycle frame, wherein when detached from the bicycle frame, the accessory carrier only leaves a fixed seat conformable to the periphery of the bicycle frame, so the fixed seat will not interfere with the cyclist's riding or scrape the cyclist's skin.

Detachable accessory carrier for bicycle