text:
An electrochemical cell stack comprises a plurality of membrane electrode assemblies interposed between pairs of separator plates. The stack comprises adhesively bonded layers. Preferably each membrane electrode assembly is adhesively bonded to the adjacent pair of separator plates. The adhesive bond between the plate and membrane electrode assembly preferably provides a substantially gas and liquid-tight seal around the perimeter of the electrochemically active area of the membrane electrode assembly and around any fluid manifold openings formed therein. Alternatively, or in addition, adjoining pairs of separator plates in an electrochemical cell stack may be adhesively bonded together. Such pairs of adhesively bonded plates may define cooling spaces between neighboring cells. Stacks comprising a plurality of individual cell modules may be formed, each module comprising a membrane electrode assembly bonded to a pair of separator plates.
1. An electrochemical cell comprising:
a first separator plate;
a second separator plate;
a membrane electrode assembly interposed between said first and second separator plates, said membrane electrode assembly comprising a polymer electrolyte membrane interposed between first and second electrode layers; and
a substantially gas and liquid impermeable adhesive bond formed between a portion of said membrane, said first and second electrodes, and each of said separator plates, wherein said adhesive bond is formed by an adhesive material, and wherein said membrane electrode assembly, said first and second separator plates, and said adhesive bond form a unitary structural unit.
2. The electrochemical cell of
3. The electrochemical cell of
4. The electrochemical cell of
5. The electrochemical cell of
6. The electrochemical cell of
7. The electrochemical cell of
8. An electrolyzer or fuel cell stack comprising a plurality of membrane electrode assemblies each interposed between a pair of separator plates, each of one of said membrane electrode assemblies comprising:
a solid polymer electrolyte membrane interposed between said first and second electrodes;
an adhesive bond between a portion of each said membrane, said first and second electrodes and a respective pair of said separator plates, thereby forming an adhesively bonded unitary structural unit,
wherein said stack comprises a plurality of unitary structural units.
9. The electrochemical cell stack of
10. The electrochemical cell stack of
11. The electrochemical cell stack of
12. An electrochemical cell stack comprising a plurality of membrane electrode assemblies each interposed between a pair of substantially fluid impermeable separator plates, said stack comprising adjoining said separator plates which are adhesively bonded together.
13. The electrochemical cell of
14. The electrochemical cell stack of
15. The electrochemical cell stack of
16. An electrochemical cell stack comprising:
a plurality of electrochemical cells, each cell comprising:
a first separator plate having outer and inner surfaces;
a second separator plate having outer and inner surfaces;
a membrane electrode assembly having a polymer electrolyte membrane interposed between electrodes, the membrane electrode assembly being interposed between the inner surfaces of the first and second separator plates;
wherein, in at least one of the cells in the cell stack, the outer surface of the first separator plate comprises first and second grooves, the first groove being sized to receive a bead of adhesive prior to assembly of the cell stack, the second groove being spaced apart from the first groove, and the outer surface of the first separator plate of the at least one cell abuts the outer surface of the second separator plate of an adjacent electrochemical cell, at least a passage portion of the first separator plate between the first and second grooves being configured to allow adhesive to pass from the first groove to the second groove during assembly of the cell stack.
17. The cell stack of
18. The cell stack of
19. The cell stack of
20. The cell stack of
21. A plate for an electrochemical cell, for use in combination with other electrochemical cells, to form a cell stack, the plate comprising:
an outer surface configured to abut the outer surface of another plate when the cell stack is assembled, the outer surface having first and second grooves, the first groove being sized to receive a bead of adhesive prior to assembly of the cell stack, the second groove being spaced apart from the first groove, at least a passage portion of the plate between the first and second grooves being configured to allow adhesive to pass from the first groove to the second groove during assembly of the cell stack.
22. The plate of
23. The plate of
24. The plate of
25. The plate of
26. A method for bonding a first separator plate in an electrochemical cell stack to a second separator plate in the cell stack, the method comprising:
providing a first groove in a first mating surface of the first separator plate;
providing a second groove in the first mating surface, the second groove being at least substantially parallel with the first groove along at least a portion of the first groove;
providing an elongated finger separating the second groove from the first groove;
depositing a bead of adhesive in the first groove;
abutting a second mating surface of the second separator plate against the first mating surface of the first separator plate to displace a portion of the bead of adhesive out of the first groove, and
receiving at least some of the displaced portion of the bead of adhesive in the second groove.
27. The method of
28. The method of
29. The method of
30. The method of
31. The method of
32. The method of
This application is a continuation of U.S. patent application Ser. No. 09/048,817 filed Mar. 26, 1998, entitled "Polymer Electrolyte Membrane Electrochemical Cells and Stacks with Adhesively Bonded Layers", now U.S. Pat. No. 6,080,503 issued Jun. 27, 2000.
The present invention relates to electrochemical energy converters with a polymer electrolyte membrane (PEM), such,as fuel cells or electrolyzer cells or stacks of such cells, wherein the cells or stacks comprise adhesively bonded layers.
Electrochemical cells comprising polymer electrolyte membranes (PEMs) may be operated as fuel cells wherein a fuel and an oxidant are electrochemically converted at the cell electrodes to produce electrical power, or as electrolyzers wherein an external electrical current is passed between the cell electrodes, typically through water, resulting in generation of hydrogen and oxygen at the respective electrodes of the cell.
FIG. 1 illustrates a typical design of a conventional electrochemical cell comprising a PEM, and a stack of such cells. Each cell comprises a membrane electrode assembly (MEA) 5 such as that illustrated in an exploded view in FIG. 1a. MEA 5 comprises an ion-conducting PEM layer 2 interposed between two electrode layers 1,3 which are typically porous and electrically conductive, and comprise an electrocatalyst at the interface with the adjacent PEM layer 2 for promoting the desired electrochemical reaction. The electrocatalyst generally defines the electrochemically active area of the cell. The MEA is typically consolidated as a bonded laminated assembly. In an individual cell 10, illustrated in an exploded view in FIG. 1b, an MEA is interposed between a pair of separator plates 11, 12, which are typically fluid impermeable and electrically conductive. The cell separator plates are typically manufactured from non-metals such as graphite or from metals, such as certain grades of steel or surface treated metals, or from electrically conductive plastic composite materials. Fluid flow spaces, such as passages or chambers, are provided between the plate and the adjacent electrode to facilitate access of reactants to the electrodes and removal of products. Such spaces may, for example, be provided by means of spacers between separator plates 11, 12 and corresponding electrodes 1, 3, or by provision of a mesh or porous fluid flow layer between separator plates 11, 12 and corresponding electrodes 1, 3. More commonly channels (not shown) are formed in the face of the separator plate facing the electrode. Separator plates comprising such channels are commonly referred to as fluid flow field plates. In conventional PEM cells, resilient gaskets or seals are typically provided between the faces of the MEA 5 and each separator plate 11, 12 around the perimeter to prevent leakage of fluid reactant and product streams.
Electrochemical cells with a ion-conductive PEM layer, hereinafter called PEM cells, are advantageously stacked to form a stack 100 (see FIG. 1d) comprising a plurality of cells disposed between a pair of end plates 17, 18. A compression mechanism (not shown) is typically employed to hold the cells tightly together, maintain good electrical contact between components and to compress the seals. In the embodiment illustrated in FIG. 1c, each cell 10 comprises a pair of separator plates 11, 12 in a configuration with two separator plates per MEA. Cooling spaces or layers may be provided between some or all of the adjacent pairs of separator plates in the stack assembly. An alternative configuration has a single separator plate or "bipolar plate" interposed between pairs of MEAs, contacting the cathode of one cell and the anode of the adjacent cell, thus resulting in only one separator plate per MEA in the stack (except for the end cell). The stack may comprises a cooling layer interposed between every few cells of the stack, rather than between each adjacent pair of cells.
The cell elements described have openings 30 formed therein which, in the stacked assembly, align to form fluid manifolds for supply and exhaust of reactants and products and, if cooling spaces are provided, for a cooling medium. Again, resilient gaskets or seals are typically provided between the faces of the MEA 5 and each separator plate 11, 12 around the perimeter of these fluid manifold openings to prevent leakage and intermixing of fluid streams in the operating stack.
In the future it is anticipated that a major area of application for PEM fuel cells will be for electrical power generation in stationary power plants and portable power generation systems, and for propulsion in motor vehicles. For these applications, a PEM fuel cell service life of at least 10 years is desirable. Production costs are important and will play a central role in the successful commercialization of PEM fuel cells for these applications. Other important considerations when designing a PEM cell are simplicity and cost-effectiveness of maintenance and repair.
The present invention relates to improved sealing and construction of individual PEM cells and stacks of such cells. Conventional PEM cell sealing mechanisms generally employ resilient gaskets made of elastomeric materials, which are typically disposed in grooves in the separator plates or MEAs, for example, as described in U.S. Pat. Nos. 5,176,966 and 5,284,718. Over the course of an electrochemical cell's service life the elastomeric gaskets are subjected to prolonged deformation and sometimes a harsh operating environment. Over time such gaskets tend to decrease in resilience, for example due to compression set and chemical degradation, and may become permanently deformed. This impacts negatively on the sealing function and can ultimately lead to an increased incidence of leaks.
With such gasketed plates, the plastic deformation of the plates increases as the full force of pressure on the sealing area of the plate is continuously applied. Moreover, an uneven gasket pressure force distribution along the length of the stack, with a minimum in the center, can be observed in stacks using such a sealing mechanism. Thus, the sealing elements of the cells are typically exposed to higher pressure in the end plate areas in order to guarantee adequate sealing performance in the center cells of the stack. Increased sealing pressure applied to the cells in the end plate areas may then lead to increased plastic deformations and a shorter time to gasket failure.
The assembly of a PEM cell stack which comprises a plurality of PEM cells each having many separate gaskets which must be fitted to or formed on the various components is labor-intensive, costly and generally unsuited to high-volume manufacture due to the multitude of parts and assembly steps required. Further, in the design and manufacture of PEM cells, in order to achieve the desired specifications, such as increased power density, there is a desire to make the individual cell elements thinner. Accordingly, there will be finer dimensional tolerances required for such thin cell elements and it will become more difficult to design gaskets which will maintain high dimensional tolerances, despite the use of highly elastic materials, as even highly elastic materials have a limited elastic deformation range.
With conventional PEM cell designs, it is sometimes difficult to remove and repair an individual cell or to identify or test which cells in a stack may require repair. Furthermore, disassembly of a stack consisting of multiple cells each comprising separate cell components can be very costly as in many instances, after the removal of one cell, the gaskets of all the remaining cells may need to be replaced before the stack can be reassembled and reused.
Another disadvantage of conventional PEM cells arises because the PEM typically projects beyond the edges of the electrodes and cell separator plates around the perimeter and around manifold openings. The projecting portion of the PEM may serve to avoid short circuits between plates, and it typically contacts and cooperates with the gaskets to form the fluid seal between the MEA and separator plates. However, such designs tend to leave the PEM edge exposed to air and/or reactant or coolant streams. Exposure to air or other dry gas streams can cause drying of the PEM beginning from the edge and moving towards the center. Drying of the membrane can lead to permanent damage to the membrane, reduced cell performance and ultimately malfunction of the PEM cells. Exposure of the PEM edge to some coolants and other streams can result in physical and/or chemical damage to the membrane or electrodes.
German Published Patent Application No. DE 44 42 285 describes a PEM cell stack where individual components of the stack are mechanically pressed together with a frame element or clamp of U-shaped cross-section. Specifically, the edge portions of two separator plates are pressed against the membrane, which is disposed between them, to form a gas-tight seal.
European Published Patent Application EP 0 331 128 and related U.S. Pat. No. 4,786,568 disclose a liquid electrolyte fuel cell with a porous electrode substrate which has a sealant material injected into a marginal edge portion thereof.
European Patent 0 122 150 describes a fuel cell stack with liquid, fixed electrolytes. In this stack array, two adjacent, porous and gasbearing plates are bonded or glued together across their entire surface, in a face-to-face bond. The purpose of this arrangement is to keep the gases in the two gas-bearing plates separated from one another.
In European Patent 0 083 937 and related U.S. Pat. No. 4,397,917, individual components of a fuel cell stack are glued together with an adhesive material. The purpose of this arrangement is to solidly join the components to form a stack, and not to reliably seal the gas spaces.
German Published Patent Application No. 19 64 811 discloses a fuel cell stack where the electrodes are attached inside a sectional plastic frame, respectively, and where the sectional frames are glued together in a gas and liquid-tight manner.
An improved electrochemical PEM cell uses an adhesive bonding agent between individual PEM cell components and/or between adjacent PEM cells in a stack. The present approach provides a simplified PEM cell and stack design with a reduced part count, and associated manufacturing and cost benefits. Sealing is generally more reliable with this approach, and embodiments of the present construction may permit easier stack disassembly, testing, repair and maintenance.
In one embodiment, an electrochemical PEM cell comprising a membrane electrode assembly interposed between a pair of separator plates further comprises a substantially gas and liquid impermeable adhesive bond between each separator plate and the MEA in those regions of the cell where sealing is necessary or desirable. Thus, adhesive materials (otherwise commonly referred to as adhesives, bonding agents, glues or cements) are employed to form a seal and bond, for example, around the perimeter of the electrochemically active area of the MEA and around fluid manifold openings formed in the cell elements, while consolidating individual components of the PEM cell into a unitary structural unit. Preferably an adhesive bond, and thereby a seal, is formed between each separator plate and the membrane of the MEA. In the present approach the MEA is firmly bonded or adhered to the separator plates such that force would be required to separate the components. This contrasts with conventional PEM cell elastomeric seals or gaskets which may be attached to one component but are not bonded to both components between which they are forming a seal.
In the MEAs, the polymer electrolyte membrane may extend or protrude beyond the edges of the electrodes or may be coextensive with the electrodes. Either way, in preferred embodiments, the adhesive bonding agent encapsulates edge portions of the polymer electrolyte membrane. Thus, the adhesive bonding agent covers the cross-sectional edge of the membrane in addition to adjacent portions of the membrane's major surfaces. The adhesive may be impregnated into the porous electrode structure in the edge portions thereof. Besides providing a reliable, gas and liquid-tight bond of the elements, such an arrangement also protects the membrane from drying-out and exposure to the ambient environment and/or fluid streams in an operating cell.
The adhesively bonded electrochemical PEM cells described above may also be stacked or layered to form a PEM cell stack. In such a stack, the anode separator plate of one cell may also serve as the cathode separator plate of an adjacent cell, the bipolar separator plates being adhesively bonded to two MEAs disposed on opposite sides thereof. In this way some of all of the cells in the stack may be adhesively bonded together. Further stack components such as end plates and bus plates may also be adhesively bonded to adjacent components if so desired.
Alternatively the stack may comprise a plurality of stacked individual "PEM modules", each PEM module comprising a membrane electrode assembly interposed between and adhesively bonded to a pair of separator plates. Stacked PEM modules may be electrically connected in parallel, but are more commonly connected in series through plate-to-plate contact of adjacent modules. The stacked PEM modules are preferably compressed between two end plates in order to maintain good electrical plate-to-plate contact between adjacent modules.
It can be advantageous to build PEM cell stacks comprising a plurality of PEM modules which are not adhesively bonded to each other, as this may allow for easier identification of defective modules and subsequent repair or replacement, as individual modules can be removed and tested without damage to the sealing mechanisms of other cells in the stack.
However, in an alternative embodiment of a stack comprising PEM modules, separator plates of adjacent PEM modules may be adhesively bonded together. They may be bonded across substantially their entire contacting surfaces or, similar to the adhesive bond between the MEA and each separator plate, the separator plates of adjacent modules may be joined with an adhesive around their perimeter and around any fluid manifold openings. The two adjacent separator plates may define a cooling space through which a coolant stream is directed in an operating stack. For example, cooling spaces typically take the form of grooves formed in the surface of at least one of the two adjacent separator plates. The adhesive bond between adjacent separator plates preferably provides a substantially gas and liquid impermeable perimeter seal for the cooling space.
Electrochemical PEM cell stacks comprising cooling layers formed by adhesively bonding pairs of adjacent separator plates may also be used in stacks where the PEM cell MEAs are not adhesively bonded to the separator plates. In this case, conventional sealing mechanisms could be used to seal around the MEAs.
In the embodiments described above, preferred adhesives are physically and chemically stable and compatible with the PEM cell and/or stack components and with the reactant, product and coolant streams, in the cell operating environment. For example, the adhesives used are preferably compatible with the electrocatalyst and polymer electrolyte membrane, particularly if the adhesive will be in direct contact with the membrane and/or electrodes. For contact with the MEA and/or reactants, adhesives which are substantially ion-impermeable, or at least have a low ion permeability, and which are stable in an acidic environment are preferred. The adhesive may form a rigid bond or a resilient bond. The adhesive may be selected to be electrically conductive or electrically insulating depending on the components to be bonded. For example, if the adhesive is forming a plate-to-plate bond between adjacent separator plates or PEM modules in a series connected stack, an electrically conductive adhesive will generally be preferred. However, if the adhesive is encapsulating the edge portion of the membrane and interconnecting the anode and cathode electrodes or plates of a single PEM cell, the adhesive should be electrically insulating to avoid short circuiting the cell. The adhesive is preferably a flow processable or formable liquid or paste, however adhesive films may be used. The following are merely examples of adhesive bonding agents which may be suitable for use in some of the described embodiments:
epoxy resins, such as, for example, 9223-2 (manufacturer: 3M) or AY 105/HY991 (manufacturer: CIBA);
methacrylate resins;
PUR, such as, for example, Araldite 2018 (manufacturer: CIBA); and
ALIPS, such as, for example, FEC2234 (manufacturer: Morton).
The adhesive may be applied to the various PEM cell components using a variety of techniques or processes including, but not limited to, screen printing, dispensing, spraying, roll coating and injection molding.
In any of the embodiments described above the electrochemical PEM cell is preferably a PEM fuel cell or an electrolyzer cell. However, the present approach may be applicable to other types of electrochemical cells such as batteries and methanol/air cells.
Furthermore, the present approach is applicable with practically any cell geometry or configuration such as, for example, square or round embodiments. Moreover, the present approach may also be used in designs where the fluid supply and exhaust manifolds are external manifolds located outside the active cell surface or internal manifolds formed by aligned openings within the electrochemically active area of the cells.
The preferred embodiments of the invention will be explained in more detail with reference to the figures:
FIGS. 1a, 1 b, 1 c and 1 d together illustrate an exploded view of a conventional electrochemical PEM cell stack;
FIG. 2 is a top plan view of an MEA showing an embodiment of the invention with an adhesive forming a perimeter seal and bond around a major surface of the MEA and the manifold openings formed therein;
FIGS. 3a, 3 b, 3 c and 3 d depict sectional views of edge regions of a PEM module showing several configurations of the perimeter adhesive seal which bonds a pair of separator plates to an MEA;
FIGS. 4a, 4 b and 4 c depict. sectional views of edge regions of a pair of separator plates showing several configurations of the adhesive seal which bonds the two adjacent separator plates together; and
FIGS. 5a and 5 b depict sectional views of edge regions of a PEM module showing several configurations of the perimeter adhesive seal between the MEA and separator plates, where the membrane edge is encapsulated by an adhesive.
With reference to FIG. 2 which shows a plan view of a major surface of an MEA 5, adhesive bonding agent 50, used to seal the MEA to the adjacent separator plate around the fluid flow spaces, is located in the edge areas of MEA 5, circumscribing the electrochemically active area 40 of a major surface of MEA 5. MEA 5 has three fluid inlet manifold openings 30 a, 32 a and 36 a, via which the reactants and, if required, a cooling medium may be supplied. Corresponding fluid outlet manifold openings 30 b, 32 b and 36 b are also provided. Depending on the cell design and whether or not a particular fluid is to be directed to the adjacent fluid flow space, the individual manifold openings may or may not have adhesive forming a seal around them.
In the MEA example depicted by FIG. 2, manifold openings 36 a and 36 b, which are not equipped with a adhesive perimeter seal, serve for exhausting and supplying a first reactant stream. Openings 30 a, 30 b and 32 a, 32 b, which are equipped with perimeter adhesive seals, serve for exhausting and supplying a second reactant and a cooling medium, respectively.
With reference again to FIG. 2, fluid manifold openings 30, 32, and 36 are arranged inside the electrochemically active area of MEA 5. Adhesive bonding agent 50, used for sealing the gas spaces, runs along the outer edges of MEA 5. However, in a further embodiment (not shown) it is also possible to arrange the openings outside the electrochemically active area of MEA 5 (by analogy with FIG. 5 of European Patent Publication EP 0 604 683 A1 which is incorporated herein by reference). In such an embodiment, the adhesive bonding agent used for sealing the gas spaces may run not along the outer edge of the MEA, but along the edge of the electrochemically active area of the MEA.
MEA 5 is thus adhesively joined with the adjacent separator plates to form a consolidated mechanical unit by means of an adhesive. The bond provides a gas and liquid-tight seal.
The following are examples of possible MEA configurations:
(a) An MEA comprising a polymer electrolyte membrane, which is not completely covered by porous electrode layers (comprising electrocatalyst) bonded to its two major planar surfaces or faces. The membrane extends or protrudes beyond the electrodes around the perimeter of the MEA and around any manifold openings formed therein; and
(b) An MEA comprising a polymer electrolyte membrane with adjacent porous electrode layers on both sides, which are bonded to the membrane and cover substantially the entire surfaces of the membrane. The membrane is coextensive with the electrodes.
These and other MEA configurations may be used in the embodiments described.
The sectional views of FIG. 3, which each show the edge portion of an individual PEM module, illustrate three examples of different separator plate designs used to accommodate an adhesive seal. The respective MEA 5, comprises polymer electrolyte membrane 2 and two porous electrodes 1, 3 disposed adjacent the membrane faces. Cell separator plates 11 and 12 are disposed on either side of MEA 5. Cell separator plates 11 and 12 have grooves 20 and 21 on their respective surfaces facing MEA 5, forming fluid reactant flow passages adjacent electrodes 1 and 3.
The specific design of the adhesive bond may take many forms, in cooperation with the configuration of the PEM cell components, such as, for example, separator plates 11 and 12, as exemplified by the embodiments shown in FIGS. 3a, 3 b, 3 c, and 3 d.
In the embodiments of FIG. 3, a gas and liquid-tight bond is formed between MEA 5 and two adjacent separator plates 11 and 12. In FIGS. 3a, 3 b and 3 c, the adhesive bonding agent 50 contacts the membrane 2 on each side. The membrane 2 may or may not extend significantly beyond the electrodes 1,3, as described above. If the membrane does not protrude, the bond is achieved by impregnating essentially the entire thickness of a portion of the porous electrode layers in the sealing regions with adhesive bonding agent 50, so that it contacts the membrane. Even if the membrane does protrude it is advantageous to impregnate at least a narrow strip of the porous electrodes with the adhesive. For these embodiments the adhesive bonding agent 50 is generally applied to the MEA, and the MEA 5 is consolidated with the separator plates 11, 12 immediately after the application of adhesive or at least before full hardening of the adhesive. Openings for fluid manifolds may be sealed in the same fashion.
In the embodiment depicted in FIG. 3b, a fixed distance between cell separator plates 11 and 12 and membrane 2 is achieved in the sealing region through a support structure in the form of one or more support ribs 55, which are formed as protrusions on cell separator plates 11 and 12. This may provide a more uniform layer thickness of adhesive bonding agent 50 between membrane 2 and plates 11, 12.
In the embodiment depicted in FIG. 3c, grooves 54 are located on the surfaces of separator plates 11 and 12 facing MEA 5, respectively, to accommodate adhesive. Grooves 54 may compensate for imprecision in the applied adhesive dosages and may ensure a sufficient quantity of adhesive to form an adequate bond can be accommodated between the components. Furthermore, grooves 54 increase the possible range of resilience for compensating thermal expansion when an elastic or resilient adhesive is used.
In another embodiment depicted in FIG. 3d, the sealing region of the porous electrode layers of MEA 5 is impregnated with a sealant or adhesive material 52. After material 52 has hardened, the firm bond of MEA 5 with cell separator plates 11 and 12 is achieved in a second step by means of adhesive bonding agent 51. Adhesive films, for example, may be used as adhesive bonding agent 51.
As explained above, in a PEM cell stack, cooling spaces may be arranged between adjacent individual cells. The distribution of the cooling spaces within the stack is a matter of design choice. For example, individual cells and cooling spaces may be arranged alternately so that each individual cell has a corresponding cooling space. However, other arrangements are also possible, for example, another arrangement may provide for a cooling space after every second or third cell. With reference to FIG. 4, such cooling spaces 25 may be defined by a pair of adjacent separator plates 11, 12, one from each of the two adjacent individual PEM cells. Cooling spaces 25 are formed by depressions, for example, grooves or channels formed in at least one of the two cell separator plates 11, 12.
Similar to the sealing of the reactant fluid spaces described above with reference to FIG. 3, it is desirable to seal the cooling spaces by means of an adhesive bond between the two separator plates 11, 12 which define the cooling spaces. Preferably, an adhesive is used to seal around the perimeter of the separator plates 11, 12 and around fluid manifold openings in the plates. Such cooling layers, formed by adhesively bonded plates, may be used in stacks with conventional cells where the MEAs are not bonded to the separator plates, or in combination with the approach described above.
Examples of preferred embodiments of adhesive sealing around the cooling spaces between adjacent plates are depicted in FIGS. 4a, 4 b and 4 c which show the edge area of two adjacent separator plates 11 and 12, and grooves in one of the separator plates 12 form cooling spaces 25. In the embodiment depicted in FIGS. 4a and 4 b, groove 71 in plate 12 is used to accommodate most of the adhesive 50. Groove 71 facilitates the application of the adhesive material 50, provides an enclosure for the adhesive material and permits full contact between separator plates 11 and 12 which may be pressed together until contact is made. In the embodiment of FIG. 4a, an adhesive overflow groove 72 is provided. With reference to the embodiment of FIG. 4c, an adhesive material film 53 or an adhesive material foil is located between the two separator plates 11, 12 to create a firm bond. The plates may be adhesively bonded across substantially their entire contacting surfaces. If the plates are to be electrically connected it is preferable to use an electrically conductive adhesive.
FIG. 5 shows two embodiments of an adhesively bonded PEM module which may protect the membrane, for example, by reducing the tendency for the membrane to dry out. In the embodiment of FIG. 5a, the cross section on the left depicts the edge area of a PEM module surrounding a fluid manifold opening 30, which forms part of a fluid manifold, and the cross section on the right depicts the perimeter of the PEM module. Separator plates 11 and 12 are adhesively bonded to MEA 5 as described for FIG. 3a. Unlike in FIG. 3a, however, adhesive bonding agent 50 encapsulates the edge portion of the membrane 2, enclosing it on three sides, where it would otherwise be exposed and vulnerable to damage. This can reduce or prevent the drying-out of polymer electrolyte membrane 2 at the edges. In order to prevent a short circuit current between separator plates 11 and 12 across an individual cell via the adhesive bonding agent 50, the bonding agent must be electrically non-conductive in this design.
The embodiment depicted in FIG. 5b shows the edge area of a stack comprising several stacked PEM modules. MEA 5 and corresponding separator plates 11 and 12 are shown, as well as cooling spaces 25 located between the individual cells. The adhesive bond between the individual elements is achieved in accordance with the explanations given above. In addition, layer 59 made of an adhesive bonding agent, may be applied onto or in the stack. Layer 59 covers, in particular, the edge faces of the polymer electrolyte membrane inside MEAs 5, protecting the membrane from drying out.
FIG. 5b also illustrates an electrolyzer or fuel cell stack comprising a plurality of membrane electrode assemblies 5 each interposed between a pair of separator plates 11 and 12. The stack comprises adjoining separator plates 11 and 12 that are adhesively bonded together by an adhesive bond 50. In a preferred arrangement, adjoining separator plates 11 and 12 define cooling spaces 25 therebetween., and the adhesive bond 50 between the adjoining separator plates forms a substantially gas and liquid-tight seal around cooling space 25. Cooling spaces 25 preferably comprise grooves formed in at least one of adjoining separator plates 11 and 12. As shown in FIG. 1, the membrane electrode assemblies 5 and separator plates 11 and 12 preferably have a plurality of aligned fluid manifold openings 30 formed therein for the supply and exhaust of fluid streams, and the adhesive bond between adjoining separator plates 11 and 12 circumscribes at least one of the manifold openings.
In order to promote a strong and lasting adhesive bond, it may be advantageous to subject the surfaces of the components to be bonded to the following surface treatments:
Chemical grafting (reactive molecules on the surface)
Corona/Plasma treatment process
Ion procedure
Flaming (Silicon procedure).
As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the spirit or scope thereof. Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the following claims.
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http://www.regmovies.com/Theatres/Theatre-Folder/Regal-O-Fallon-Stadium-14-8098 This fourteen-screen theater is located off Caledonia Drive in O'Fallon, Missouri. It features 3D presentation, digital projection and a snack bar and arcade in the lobby. More >>
http://www.regmovies.com/Theatres/Theatre-Folder/Regal-St-Louis-Mills-Stadium-18-IMAX-7461 This eighteen-screen theater is located off St. Louis Mills Boulevard in Hazelwood. It features IMAX RealD 3D, wheelchair-accessible seating and a snack bar in the lobby. More >>


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Sweet Succulence Lipstick ($15.00 for 0.10 oz.) is described as a "deep glossy plum [with a Lustre finish]." It's a purplish berry with cool undertones. It was semi-sheer, and it had a tendency to settle into lip lines and took some blending to apply evenly. It lasted three hours on me. NARS Valparaiso is brighter, more opaque, matte. NARS Afghan Red is more matte. MAC Red Dwarf is slightly pinker. MAC Positively Dashing is lighter. MAC Deliciously Forbidden is much pinker. MAC Plum Bright is purpler. Guerlain Bee is more berry-colored.
See comparison swatches.


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Open Method (ADO Stream)
Opens a Stream object to manipulate streams of binary or text data.
When a Record object is passed in as the source parameter, the UserID and Password parameters are not used because access to the Record object is already available. Similarly, the Mode of the Record object is transferred to the Stream object. When Source is not specified, the Stream opened contains no data and has a Size of zero (0). To avoid losing any data that is written to this Stream when the Stream is closed, save the Stream with the CopyTo or SaveToFile methods, or save it to another memory location.
An OpenOptions value of adOpenStreamFromRecord identifies the contents of the Source parameter to be an already open Record object. The default behavior is to treat Source as a URL that points directly to a node in a tree structure, such as a file. The default stream associated with that node is opened.
While the Stream is not open, it is possible to read all the read-only properties of the Stream. If a Stream is opened asynchronously, all subsequent operations (other than checking the State and other read-only properties) are blocked until the Open operation is completed.
In addition to the options that were discussed earlier, by not specifying Source, you can create an instance of a Stream object in memory without associating it with an underlying source. You can dynamically add data to the stream by writing binary or text data to the Stream with Write or WriteText, or by loading data from a file with LoadFromFile.


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(Featured Lana Del Rey Image Via: T Magazine)
Some celebrities are KILLIN' it on the style tip these days- going hard enough to be featured in our Street Style section! Unfortunately, these starlets' outfits are often WAY over our post-grad budgets but instead of thinking we can't look as good as the Solange's and Kate Bosworth's of the world, we've put together different ways to GET THEIR LOOKS FOR LESS. Find out where to snatch up all the goods below:
+Miley Cyrus
Miley Cyrus was out walking her dog (with boyfriend Liam Hensworth) in an amazing American Apparel getup! She wore a black spandex ruched bodysuit and High Waist Denim jeans from the basics store, along with fab red heels and cute aviators. Get the look for nearly $100 less:
+Kate Bosworth
Kate Bosworth was spotted wearing Isabel Marant wedge sneakers, a pretty chiffon maxiskirt, and a sporty-style sweatshirt while leaving the Byron & Tracey Salon in Beverly Hills. Here's how to get the wedge sneaker look without the $700 pricetag:
+Solange Knowles
Solange ran errands on Mother's Day in a yellow romper, paired with studded Alaia sandals, totally retro cat eye shades, and a red bag. Find out how to look just as POPPIN' for WAY less:
+Lana Del Rey
+Alexandra Burke
British singer Alexandra Burke strutted her stuff at Chloe Green's Topshop party in a vintage red leather bomber jacket and eye catching patterned tights. Here's how to get her look for half the price:


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Vehicle parked partially on an unpaved surface visible from the street
Vehicle parked on an unpaved surface visible from the street (private property)
"Inoperable Vehicle" means any motor vehicle as defined by the California Vehicle Code and/or Livermore Municipal Code that cannot be started and moved under its own power without the assistance of another person (other than the operator), vehicle or gravity.
Partially or fully dismantled and/or wrecked vehicles are considered inoperable and shall not be stored in any driveway, driveway extension or other area on private property in public view. Vehicles with flat, under-inflated or missing tires or vehicles with a damaged or missing major component(s) required for conventional or safe use are considered inoperable. Ex. Smashed windshield or missing door(s) or steering wheel
A maximum of one (1) inoperable vehicle may be parked or kept in the driveway area of a residence under the following conditions:


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Not always pretty, but a win's a win for Clemson
Swinney pleased with victory on the road
Clemson had trouble in the red-zone all game long against Maryland on Saturday, but in the end, a prolific offensive performance and the reliable toe of Chandler Catanzaro meant there was no price to pay.
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The definition of the indicators would need to specify whether energy needed to prepare land and to transport resources to the site is included. Land indicators are highly dependent on where the land is, though all the indicators have at least some site specificity. DOE could help address these indicators through more detailed studies of the potential biofuel production capacities of specific technologies in various regions of the country.
4.3.5 Information and Data Gaps
Land-use availability databases, land-suitability databases, and geo-spatial resource maps compiled specifically for the purpose of assessing the potential for algal biofuel production are incomplete (Darzins et al., 2010). A number of relevant resource maps for the United States and the world can be found in Lundquist et al. (2010), who also present a detailed geographic information systems (GIS)-based analysis of algal biofuel production in California. Continued efforts to perform meta-analyses of existing LCAs are desirable to comprehensively assess the land requirements and the most likely site locations for future algal biofuel production.
4.3.6 Effects on Social Acceptability
Part of the appeal of algae production as a renewable fuel source is the potential small land area required to produce a given quantity of energy relative to terrestrial crops. However, commercial-scale algal biofuel facilities, especially those relying on open-pond cultivation systems, still will require thousands of hectares of land to achieve sufficient economies of scale. Despite the algal industry's general focus on using marginal and degraded land for development of commercial-scale facilities, questions still may be raised as to the potential social and health-related risks of developing such large areas for the purpose of algae production.
Land in the desert Southwest is suitable for the scale-up of algae cultivation facilities because of favorable climatic conditions for algal growth. While much of the land in this region has been designated as marginal due to its inability to support food production, public support for large-scale land developments, even in the renewable-energy sector, is not guaranteed. The arid conditions and infertile soil in the desert Southwest support highly fragile ecosystems that take far longer to recover following major disturbances than ecosystems in wetter climates. These areas also contain a number of threatened or endangered species that are the focus of major conservation efforts and public awareness campaigns, such as the desert tortoise. Setbacks to the construction of commercial-scale photovoltaic facilities have resulted over concern for the vulnerability of these ecosystems, forcing solar developers to purchase additional land as conservation easements and to create wildlife rehabilitation and protection programs (BLM and DOE, 2010). The algal biofuel industry likely will face similar hurdles as it continues toward commercialization; actively engaging the public and conservation organizations during the site selection and permitting process could help overcome those barriers.
Even if algae developers have gained acceptance from the public, the definition of marginal or degraded land is fluid and depends on both the technology available for farming and the macroeconomic and geopolitical conditions at a given time. For example, land that is considered marginal and unsuitable for traditional freshwater farming today may be considered suitable in the future if a cultivar of a food crop is developed to tolerate dryer or less fertile soils. Pressure to use that land for food rather than energy production


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- Drink as much water as you can before hitting the sack and keep more by the bed to slurp if you wake in the night.
- Take a painkiller – a soluble one in water is best.
- Take an antacid to settle your stomach.
- Remember alcohol is a depressant. A tea or coffee may give you a slight temporary lift, but they may also dehydrate you further, so keep up with the water to counteract this.
- Go for a gentle stroll if you feel able and get some fresh air and light on the face.
- Avoid hair of the dog – you might think it helps but all you're doing is easing the alcohol withdrawal and delaying the problem.
- Get plenty of rest and relaxation and stay away from booze for at least 24 hours after a heavy session.
MYTH: Alcohol gives you energy, it's a stimulant
TRUTH: Alcohol is a depressant that affects the central nervous system, and can actually make you sleepy. Although the initial effects may seem stimulating, cumulatively it slows down the way you think, speak, move and react.
MYTH: Beer before liquor, never been sicker / liquor before beer, you're in the clear
TRUTH: This urban legend just isn't true. Your blood alcohol content is what determines how drunk you are. It doesn't matter what type of alcohol you choose - a drink is a drink, and too much of any combination can make you sick.
MYTH: I can sober up quickly if I need to, with a cold shower/fresh air/hot coffee
TRUTH: Taking a shower, drinking 10 cups of coffee or eating a loaf of bread will not make you sober. Only time will remove alcohol from your system; depending on your weight, it takes about one hour to eliminate one unit of alcohol.
MYTH: Drink drivers can be safe, because they drive extra carefully so they don't get pulled over
TRUTH: In 2002, alcohol was involved in 41% of all fatal crashes (NIDA). You might think you're in control, but alcohol slows down reaction time, which makes driving a car much tricker than you think - even if you've only had one drink.
MYTH: Alcohol makes sex better
TRUTH: Alcohol can make people feel less uncomfortable in a social situation. But it can keep men from getting or keeping an erection, and it can lower women's sex drives too. More importantly, alcohol can affect your decision-making ability: you might put yourself in a risky situation and think you're ready to have sex when you're not or you might not use a condom, putting you at greater risk of a sexually transmitted disease or an unwanted pregnancy.
MYTH: The worst thing that can happen if I drink too much is getting my stomach pumped
TRUTH: Alcohol poisoning can cause death. Also, if you're drunk and unconscious, you could inhale fluids from your vomit, resulting in death by asphyxiation. Long-term, heavy use of alcohol can lead to addiction (alcoholism), and can even cause a heart attack or stroke.
MYTH: Beer gets you less drunk than other drinks
TRUTH: A pint of typical-strength beer (ABV 5%), a glass of wine (250ml, ABV 11%) or a large double vodka (70ml) and coke (ABV 38-40%) are all equally intoxicating, at around 2.8 units of alcohol. It's the alcohol itself, not the type of drink it's found in, that makes you drunk although the faster you drink and absorb the alcohol, the higher your peak blood level.
MYTH: Switching between beer, wine, and spirits will make you more drunk
TRUTH: Mixing types of drinks may make you sicker by upsetting your stomach, but not more intoxicated.
MYTH: Eating a big meal, or 'coating' your stomach, before you drink will keep you sober
TRUTH: Drinking on a full stomach, or coating your stomach with a greasy or milky solution (like drinking milk before you go out) will only delay the absorption of alcohol into the bloodstream, not prevent it. However, it is best to eat a proper meal before a night out, especially foods rich in carbohydrates and proteins.
MYTH: Your body develops a tolerance to alcohol if you drink a lot regularly, so you can safely drink more
TRUTH: The more you drink the more damage your body will sustain and the greater the risks become. Tolerance is actually a warning sign that your body has started to be affected by alcohol.


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Following a public consultation on proposals to remove the abseil pole above Coire Leis, close to the summit of Ben Nevis, and to retain the Number 4 Gully Marker, the John Muir Trust can confirm that action has been taken to remove the Coire Leis poles and to replace the Number 4 Gully marker with a navigational cairn.
The Trust has a presumption against new structures on the summit, and aims, through a consultation process, to remove structures that are deemed to no longer have a use, other than those that have a cultural heritage value, such as the ruins of the observatory.
However, the Trust recognises the importance of certain structures as winter navigational aids, and in determining what should happen to them looks to follow advice from organisations with appropriate expertise such as the Mountaineering Council of Scotland (MCofS).
Through the consultation, we invited interested parties to comment on proposals to:
1. Remove the abseil post at the top of Coire Leis and replace it with a cairn at the best point for making a descent from Ben Nevis.
2. Retain the Number 4 Gully marker.
The consultation closed on Monday 30 April by which time we had received 45 responses over the course of six months. The responses came mostly from individual climbers as well as representatives from associated clubs and mountain guides.
The overwhelming majority (43 out of 45) were in favour of retaining Number 4 Gully marker as a winter navigational aid. Fewer people responded to the question of the Coire Leis abseil post, but of those who did, the majority were in favour of removing it and replacing with a cairn (21 out of 27).
Following the consultation, we've been working with the Mountaineering Council of Scotland to decide the best course of action. Upon inspection of the Number 4 Gully marker, it was decided that a cairn would be preferable to the existing marker post. The marker has previously been vandalised and is unstable. It was also agreed that the Coire Leis post would be replaced with a two-metre high cairn.
The Trust and MCofS relies on the help of volunteers to undertake this sort of work. A window of good weather at the end of May allowed MCofS to mobilise a group of volunteers and some members of the RAF Kinloss Mountain Rescue Team to remove the Coire Leis post. The Number 4 Gully marker was removed at the same time.
The Coire Leis post will be replaced by a 2-metre high cairn, while the Number 4 Gully Marker will be re-instated as a 1.5 metre cairn with No.4 incised on the cap stone. This will make the marker stable and less prone to vandalism and maintenance in the future. Work will begin to build the cairns as soon as possible over the next couple of months.
Mike Daniels, head of land at the Trust said: Wed like to thank everyone who took the time to respond to the consultation on marker posts on Ben Nevis, and also the Mountaineering Council of Scotland for their help and expertise in this matter and for organising their volunteers at such short notice.
Were confident that the action taken and the measures proposed are in line with the responses we received and will meet the needs of all those who use and enjoy the Ben throughout the year.
RAF Kinloss Mountain Rescue kindly removed the posts from Coire Leis and Number 4 Gully


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franco harris
franco harris
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Franco Harris: 'Mr. Powell was a game-changer'
More than 200 people came to pay tribute to William Powell at Minerva United Methodist Church in Minerva, Ohio, on Wednesday morning, among them Pittsburgh Steelers' great Franco Harris. "Mr. Powell was a game-changer,'' Harris...
Wednesday, 1/6/2010 at 6:52PM
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- Franco Harris,
- Joe Steranka,
- William Powell
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Oldman's Brave New World of Wine
May 5, 2011 7:00pm - 8:00pm
May 5, 2011 7:00pm - 8:00pm
Room Offsite
Spend an evening with renowned wine expert Mark Oldman, '91, MA '93, JD '98, for a professional tasting to learn about moderate-cost and maximum-appeal wines. Oldman is one of the country's top wine experts, the lead judge on PBS's The Winemakers and a regular on Martha Stewart Living Radio's Living Today.
The price is $30 for general admission and $25 for alumni who graduated between 2000-2010. Admission includes delicious local food and wine pairings plus a copy of the book Oldman's Brave New World of Wine.
Space is limited, please register soon.CLICK HERE TO REGISTER
For questions, please contact the Office of Alumni Relations at 650.723.2730 or firstname.lastname@example.com here to see the book's trailer
- SLS Alumni Relations
- alumni.relations@


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Below is the poem entitled How do I capture the man of my dreams which was written by poet
Smith. Please feel free to comment on this poem. However, please remember, PoetrySoup is a place of encouragement and growth.
Read Poems by
Sophia Smith
How do I capture the man of man of my dreams. When I see him and he delights
me, I will talk to him. If he make my heart please. I will club him over the head and
rendering him half dead. Thus, I will take him in my bed and when he awoke, he will
not protest because he will be too week to leave; consequently, surrender is right
to wed me by a minister and a witness to prove our joint being. And when, he is fully
aware, he won't resist. He will leave to get his belongings and move in with me; in
this way, we become one - the man of dreams and me.


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Caroline Nokes is the UKs 'most responsive MP', according to research produced by the non-party political think-tank, My Society. Caroline topped the league table of all the UK's 650 MPs, with a response rate approaching 100%.
The independent data was produced to establish the effectiveness of writing to MPs, to see if MPs regard communicating with their constituents as important, and the data is based on over 58,000 responses to 96,000 messages sent to MPs. Caroline's response rate was secretly and independently monitored, and when assessed, she was shown to be the most responsive MP in Parliament.
My Society commented "The people of Romsey & Southampton North should rest easy. Their Conservative MP Caroline Nokes is on the case", and went on to say "she is top of our league table".
Caroline said "MPs get thousands of emails and letters each year, and if there is an issue which is causing a lot of concern, I can get 200 or more in a single day. Providing the emails or letters are not abusive, which sadly some occasionally are, I try to reply to them all. Of course, some are about very complex issues which require a lot of work with Government departments, agencies or local authorities. But, as well as being a common courtesy, I think responding to my constituents is an essential part of my job."
Caroline also explained that she is sometimes sent letters and emails from people who are not her constituents, but are writing on policy issues relating to her Select Committee work, as well as correspondence from special interest groups, trade bodies and other groups seeking to influence public policy. "Every piece of correspondence gets read by me personally, and unlike some colleagues I regard emails as an essential tool to be able to communicate quickly and very cost effectively."
The data for this research can be found here: https://www.mysociety.org/2014/06/10/how-responsive-is-your-mp/


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Copia's entrance at 1122 Washington Avenue.
Amid such spectacle, the food clamors for attention. Salmon cured with lemongrass, an appetizer, is lovely to behold, the thin slices of fish wrapped around one another to resemble a blooming flower. Unfold a petal and you're rewarded with luscious salmon, its sweetness gradually yielding to lemongrass' verdant kick. Continue reading Ian Froeb's review of Copia Urban Winery. Photos by Jennifer Silverberg.


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Reverse Data Management
Forward and Reverse Data Transformations
Database research mainly focuses on forward-moving data flows: source data is subjected to transformations and evolves through queries, aggregations, and view definitions to form a new target in- stance, possibly with a different schema. This forward paradigm underpins most data management tasks today, such as querying, data integration, data mining, etc. We contrast this forward processing with Reverse Data Management (RDM), where the action needs to be performed on the input data, on behalf of desired outcomes in the output data. Some data management tasks already fall under this paradigm, for example updates through views, data generation, data cleaning and repair. RDM is, by necessity, conceptually more difficult to define, and computationally harder to achieve. Today, however, as increasingly more of the available data is derived from other data, there is an increased need to be able to modify the input in order to achieve a desired effect on the output, motivating a systematic study of RDM.
In general, RDM problems are harder to formulate and implement, because of the simple fact that the inverse of a function is not always a function. Given a desired output (or change to the output), there are multiple inputs (or none at all) that can produce it. This is a prevailing difficulty in all RDM problems. This project aims to develop a unified framework for Reverse Data Management problems, which will bring together several subfields of database research. RDM problems can be classified along two dimensions, as shown in the table below. On the "target" dimension, problems are divided into those that have explicit and those that have implicit specifications. The former means that the desired target effect is given as a tuple-level data instance; this is the case in causality and view updates. The latter means that the target effect is described indirectly, through statistics and constraints; examples include how-to queries and data generation. On the "source" dimension, problems are divided in those that use a reference source, and those that do not. For example, view updates and how-to queries fall under the former category, while data generation under the latter.
How-To Queries
How-to queries are motivated from a related research problem within the forward processing paradigm: what-if or hypothetical queries. They use source and target data to ask questions of the form "How would the output change for a given change in the source?". They are motivated by a variety of business applications that require strategy evaluation and decisions. However, it is more meaningful for such applications to be treated under the reverse framework of how-to queries, i.e. "How should the input change in order to achieve the desired output?"
Example (Portfolio Analysis) An analyst at a brokerage company wants to investigate strategies that could achieve better returns and volatility of customer portfolios, based on the company's recommendations during the last three years. He would like to receive a list of possible modifications to the company's stock recommendations, that would achieve the desired output in the customer's portfolios (e.g. 10% return). Out of all the possible scenarios, the analyst wants to give preference to those that are closest to the company's current strategy as they would require fewer trades.
Example (Shipment Consolidation) A product supplier receives orders for various products from different clients. He would like to minimize costs by consolidating shipments to the same client. However, the supplier needs to make sure that all orders arrive within the agreed delivery window, and no shipment exceeds the maximum order size.
Example (Resource Utilization) A system administrator has access to system logs of a server cluster with information on resource allocation and utilization, and job arrival, execution, and waiting times. During peak times within the day the system can become overloaded, and job wait times reach undesirable highs. The administrator wants to determine which machines in the cluster should be kept in operation so that job wait times are bounded by a small constant, and throughput remains high, while minimizing the operational cost of the cluster (there is a cost associated with keeping a machine in operation).
Reverse Data Management
Alexandra Meliou, Wolfgang Gatterbauer, and Dan Suciu.
[ Paper], [Slides]
|Faculty (University of Massachusetts, Amherst)
|Faculty (University of Washington)


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My 2010 D22 Nissan blows a lot of black smoke, but my dealer said this was normal. I don't believe him, what do you think?
Steve Paton
No it's not normal for a modern diesel to blow a lot of smoke. It sounds like it's too rich, check the fuel pump.
Graham Smith,


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More New and Used
from Private Sellers
Dalmatia and Montenegro : With a Journey to Mostar in Herzegovia, and Remarks on the Slavonic Nationsby Wilkinson, John Gardner
Cambridge Univ Pr
Questions About This Book?
Why should I rent this book?
Renting is easy, fast, and cheap! Renting from eCampus.com can save you hundreds of dollars compared to the cost of new or used books each semester. At the end of the semester, simply ship the book back to us with a free UPS shipping label! No need to worry about selling it back.
How do rental returns work?
Returning books is as easy as possible. As your rental due date approaches, we will email you several courtesy reminders. When you are ready to return, you can print a free UPS shipping label from our website at any time. Then, just return the book to your UPS driver or any staffed UPS location. You can even use the same box we shipped it in!
What version or edition is this?
This is the 1st edition with a publication date of 3/28/2013.
What is included with this book?
- The New copy of this book will include any supplemental materials advertised. Please check the title of the book to determine if it should include any CDs, lab manuals, study guides, etc.
- The Rental copy of this book is not guaranteed to include any supplemental materials. You may receive a brand new copy, but typically, only the book itself.
Sir John Gardner Wilkinson (1797-1875) pioneered modern Egyptology and is best known for his Egyptian surveys with their detailed watercolours. His contributions to the subject earned him numerous honours as well as fellowship of the Royal Society. Wilkinson's passion for exploration led him to travel widely in Europe and the Mediterranean. In 1844, he toured Dalmatia and Montenegro, which were little-known regions in the nineteenth century. Dalmatia, a historical region of Croatia located on the eastern coast of the Adriatic Sea, was then a province of Austria and torn by ethnic conflicts. During his trip, Wilkinson gathered a significant amount of information about regional customs, architecture, history and language. This illustrated two-volume account of his travels was first published in 1848. Volume 1 charts the physical features and cultural traditions of the area, with a substantial chapter devoted to Montenegro.


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Minoring in Accounting involves the study of financial transactions. You'll learn to gather, record, analyze and communicate financial information for individuals and organizations. What do investors need to know to assess performance? What reporting issues do low-income taxpayers face? How are lost funds traced? You'll gain knowledge and skills that are important for any business or organization as you take 28 credit hours toward an accounting minor in conjunction with a different bachelor's degree major.
BuyerCorporate AccountantControllerCredit AnalystGovernment AccountantGovernment AuditorImport/Export AgentIndependent AccountantInternal AuditorLoan OfficerTaxation AccountantTreasurer
Responsiveto the needs of today's students.Relevantto the skills employers seek.Realpreparation for thoughtful living and service.
Schedule a visit today!
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The 2011 Albany Children's Book Festival was held this past weekend at the Albany Academy for Girls campus. More than 50 authors for children and teens were available for book signings and workshops throughout the day. There were many exhibitors as well, including local bookseller Barefoot Books, The Children's Literature Connection, and Skribblers Magazine.
Among the YA authors available were:
- Sarah Darer Littman
- Peter Dewitt (local)
- Aimee Ferris
- Rose Kent (local)
- Jo Knowles
- Eric Luper (local)
- Peter Marino (local)
- Amanda Marrone
- Lyn Miller-Lachmann (local)
- Micol Ostow
- Coleen Murtagh-Paratore (local)
- Melissa Walker
Aimee Ferris, Jo Knowles, Eric Luper, Micol Ostow, and Melissa Walker all spoke about the Value of Contemporary Young Adult Literature. Each of these authors have had success with the YA market.


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DVD Extra
Is that DVD you've got your eye on really worth the investment? Should you wait a few months until the "Special Edition" hits shelves? DVD Extra lights the way.
Posts filtered on Tag
"X-Men: First Class" makes use of "white-out"
As a rule, prequels tend to be more problematic than sequels, especially if you've established a franchise. The most obvious example is the "Star Wars" prequels, because the series was so established in the minds of the fan base. When George Lucas came up with the idea of the "midichlorians" to explain why the young […] [Read More]