text:
For other uses, see Asphalt (disambiguation). Note: The terms bitumen and asphalt are mostly interchangeable, Commercial Paving Contractors in Germiston except where asphalt is used as a shorthand for asphalt concrete. Natural bitumen from the Dead Sea Refined asphalt The University of Queensland pitch drop experiment, demonstrating the viscosity of asphalt
Asphalt (/ˈæsˌfɔːlt, -ˌfɑːlt/), also known as bitumen (UK English: /ˈbɪtʃəmən, ˈbɪtjʊmən/,[1] US English: /bɪˈt(j)uːmən, baɪˈt(j)uːmən/)[2] is a sticky, black, and highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product, and is classed as a pitch. Before the 20th century, the term asphaltum was also used.
The primary use (70%) of asphalt Asphalt Driveway Paving is in road construction, where it is used as the glue or binder mixed with aggregate particles to create asphalt concrete. Its other main uses are for bituminous waterproofing products, including production of roofing felt and for sealing flat roofs.
The terms "asphalt" and "bitumen" are often used interchangeably to mean both natural and manufactured forms of the substance. In American English, "asphalt" (or "asphalt cement") is commonly used for a refined residue from the distillation process of selected crude oils. Outside the United States, the product is often called "bitumen", and geologists worldwide often prefer the term for the naturally occurring variety. Common colloquial usage often refers to various forms of asphalt as "tar", as in the name of the La Brea Tar Pits.
Naturally occurring asphalt is sometimes specified by the term "crude bitumen". Commercial Paving Contractors Its viscosity is similar to that of cold molasses[6][7] while the material obtained from the fractional distillation of crude oil boiling at 525 °C (977 °F) is sometimes referred to as "refined bitumen". The Canadian province of Alberta has most of the world's reserves of natural asphalt in the Athabasca oil sands, which cover 142,000 square kilometres (55,000 sq mi), an area larger than England.
The word "asphalt" is derived from the late Middle English, in turn from French asphalte, based on Late Latin asphalton, asphaltum, which is the latinisation of the Greek ἄσφαλτος (ásphaltos, ásphalton), a word meaning "asphalt/bitumen/pitch" which perhaps derives from ἀ-, "without" and σφάλλω (sfallō), "make fall". Asphalt Sealcoating Companies the first use of asphalt by the ancients was in the nature of a cement for securing or joining together various objects, and it thus seems likely that the name itself was expressive of this application. Specifically, Herodotus mentioned that bitumen was brought to Babylon to build its gigantic fortification wall.[11] From the Greek, the word passed into late Latin, and thence into French (asphalte) and English ("asphaltum" and "asphalt"). In French, the term asphalte is used for naturally occurring asphalt-soaked limestone deposits, and for specialised manufactured products with fewer voids or greater bitumen content than the "asphaltic concrete" used to pave roads.
The expression "bitumen" originated in the Sanskrit words jatu, meaning "pitch", and jatu-krit, meaning "pitch creating" or "pitch producing" (referring to coniferous or resinous trees). The Latin equivalent is claimed by some to be originally gwitu-men (pertaining to pitch), and by others, pixtumens (exuding or bubbling pitch), which was subsequently shortened to bitumen, thence passing via French into English. From the same root is derived the Anglo-Saxon word cwidu (mastix), the German word Kitt (cement or mastic) and the old Norse word kvada.
In British English, "bitumen" is used instead of "asphalt". The word "asphalt" is instead used to refer to asphalt concrete, a mixture of construction aggregate and asphalt itself (also called "tarmac" in common parlance). Bitumen mixed with clay was usually called "asphaltum",[13] but the term is less commonly used today.[citation needed]
Diverging diamond interchange
In Australian English, "bitumen" is often used as the generic term for road surfaces.
In American English, "asphalt" is equivalent to the British "bitumen". However, "asphalt" is also commonly used as a shortened form of "asphalt concrete" (therefore equivalent to the British "asphalt" or "tarmac").
In Canadian English, the word "bitumen" is used to refer to the vast Canadian deposits of extremely heavy crude oil,[14] while "asphalt" is used for the oil refinery product. Diluted bitumen (diluted with naphtha to make it flow in pipelines) is known as "dilbit" in the Canadian petroleum industry, while bitumen "upgraded" to synthetic crude oil is known as "syncrude", and syncrude blended with bitumen is called "synbit".[15]
"Bitumen" is still the preferred geological term for naturally occurring deposits of the solid or semi-solid form of petroleum. "Bituminous rock" is a form of sandstone impregnated with bitumen. The tar sands of Alberta, Canada are a similar material.
Neither of the terms "asphalt" or "bitumen" should be confused with tar or coal tars.[further explanation needed]
See also: Asphaltene
The components of asphalt include four main classes of compounds:
The naphthene aromatics and polar aromatics are typically the majority components. Most natural bitumens also contain organosulfur compounds, resulting in an overall sulfur content of up to 4%. Nickel and vanadium are found at <10 parts per million, as is typical of some petroleum.
The substance is soluble in carbon disulfide. It is commonly modelled as a colloid, with asphaltenes as the dispersed phase and maltenes as the continuous phase.[16] "It is almost impossible to separate and identify all the different molecules of asphalt, because the number of molecules with different chemical structure is extremely large".
Asphalt may be confused with coal tar, which is a visually similar black, thermoplastic material produced by the destructive distillation of coal. During the early and mid-20th century, when town gas was produced, coal tar was a readily available byproduct and extensively used as the binder for road aggregates. The addition of coal tar to macadam roads led to the word "tarmac", which is now used in common parlance to refer to road-making materials. However, since the 1970s, when natural gas succeeded town gas, asphalt has completely overtaken the use of coal tar in these applications. Other examples of this confusion include the La Brea Tar Pits and the Canadian oil sands, both of which actually contain natural bitumen rather than tar. "Pitch" is another term sometimes informally used at times to refer to asphalt, as in Pitch Lake.
Bituminous outcrop of the Puy de la Poix, Clermont-Ferrand, France
The majority of asphalt used commercially is obtained from petroleum.[18] Nonetheless, large amounts of asphalt occur in concentrated form in nature. Naturally occurring deposits of bitumen are formed from the remains of ancient, microscopic algae (diatoms) and other once-living things. These remains were deposited in the mud on the bottom of the ocean or lake where the organisms lived. Under the heat (above 50 °C) and pressure of burial deep in the earth, the remains were transformed into materials such as bitumen, kerogen, or petroleum.
Natural deposits of bitumen include lakes such as the Pitch Lake in Trinidad and Tobago and Lake Bermudez in Venezuela. Natural seeps occur in the La Brea Tar Pits and in the Dead Sea.
Bitumen also occurs in unconsolidated sandstones known as "oil sands" in Alberta, Canada, and the similar "tar sands" in Utah, US. The Canadian province of Alberta has most of the world's reserves, in three huge deposits covering 142,000 square kilometres (55,000 sq mi), an area larger than England or New York state. These bituminous sands contain 166 billion barrels (26.4×10^9 m3) of commercially established oil reserves, giving Canada the third largest oil reserves in the world. Although historically it was used without refining to pave roads, nearly all of the output is now used as raw material for oil refineries in Canada and the United States.
Michigan left
The world's largest deposit of natural bitumen, known as the Athabasca oil sands, is located in the McMurray Formation of Northern Alberta. This formation is from the early Cretaceous, and is composed of numerous lenses of oil-bearing sand with up to 20% oil.[19] Isotopic studies show the oil deposits to be about 110 million years old.[20] Two smaller but still very large formations occur in the Peace River oil sands and the Cold Lake oil sands, to the west and southeast of the Athabasca oil sands, respectively. Of the Alberta deposits, only parts of the Athabasca oil sands are shallow enough to be suitable for surface mining. The other 80% has to be produced by oil wells using enhanced oil recovery techniques like steam-assisted gravity drainage.
Much smaller heavy oil or bitumen deposits also occur in the Uinta Basin in Utah, US. The Tar Sand Triangle deposit, for example, is roughly 6% bitumen.
Bitumen may occur in hydrothermal veins. An example of this is within the Uinta Basin of Utah, in the US, where there is a swarm of laterally and vertically extensive veins composed of a solid hydrocarbon termed Gilsonite. These veins formed by the polymerization and solidification of hydrocarbons that were mobilized from the deeper oil shales of the Green River Formation during burial and diagenesis.
Bitumen is similar to the organic matter in carbonaceous meteorites.[23] However, detailed studies have shown these materials to be distinct.[24] The vast Alberta bitumen resources are considered to have started out as living material from marine plants and animals, mainly algae, that died millions of years ago when an ancient ocean covered Alberta. They were covered by mud, buried deeply over time, and gently cooked into oil by geothermal heat at a temperature of 50 to 150 °C (120 to 300 °F). Due to pressure from the rising of the Rocky Mountains in southwestern Alberta, 80 to 55 million years ago, the oil was driven northeast hundreds of kilometres and trapped into underground sand deposits left behind by ancient river beds and ocean beaches, thus forming the oil sands.
The use of natural bitumen for waterproofing, and as an adhesive dates at least to the fifth millennium BC, with a crop storage basket discovered in Mehrgarh, of the Indus Valley Civilization, lined with it.[25] By the 3rd millennia BC refined rock asphalt was in use, in the region, and was used to waterproof the Great Bath, Mohenjo-daro.
In the ancient Middle East, the Sumerians used natural bitumen deposits for mortar between bricks and stones, to cement parts of carvings, such as eyes, into place, for ship caulking, and for waterproofing.[3] The Greek historian Herodotus said hot bitumen was used as mortar in the walls of Babylon.
The 1 kilometre (0.62 mi) long Euphrates Tunnel beneath the river Euphrates at Babylon in the time of Queen Semiramis (ca. 800 BC) was reportedly constructed of burnt bricks covered with bitumen as a waterproofing agent.
Bitumen was used by ancient Egyptians to embalm mummies.[3][28] The Persian word for asphalt is moom, which is related to the English word mummy. The Egyptians' primary source of bitumen was the Dead Sea, which the Romans knew as Palus Asphaltites (Asphalt Lake).
Approximately 40 AD, Dioscorides described the Dead Sea material as Judaicum bitumen, and noted other places in the region where it could be found.[29] The Sidon bitumen is thought to refer to material found at Hasbeya.[30] Pliny refers also to bitumen being found in Epirus. It was a valuable strategic resource, the object of the first known battle for a hydrocarbon deposit—between the Seleucids and the Nabateans in 312 BC.
In the ancient Far East, natural bitumen was slowly boiled to get rid of the higher fractions, leaving a thermoplastic material of higher molecular weight that when layered on objects became quite hard upon cooling. This was used to cover objects that needed waterproofing,[3] such as scabbards and other items. Statuettes of household deities were also cast with this type of material in Japan, and probably also in China.
In North America, archaeological recovery has indicated bitumen was sometimes used to adhere stone projectile points to wooden shafts.[32] In Canada, aboriginal people used bitumen seeping out of the banks of the Athabasca and other rivers to waterproof birch bark canoes, and also heated it in smudge pots to ward off mosquitoes in the summer.
In 1553, Pierre Belon described in his work Observations that pissasphalto, a mixture of pitch and bitumen, was used in the Republic of Ragusa (now Dubrovnik, Croatia) for tarring of ships.
Asphalt concrete
An 1838 edition of Mechanics Magazine cites an early use of asphalt in France. A pamphlet dated 1621, by "a certain Monsieur d'Eyrinys, states that he had discovered the existence (of asphaltum) in large quantities in the vicinity of Neufchatel", and that he proposed to use it in a variety of ways – "principally in the construction of air-proof granaries, and in protecting, by means of the arches, the water-courses in the city of Paris from the intrusion of dirt and filth", which at that time made the water unusable. "He expatiates also on the excellence of this material for forming level and durable terraces" in palaces, "the notion of forming such terraces in the streets not one likely to cross the brain of a Parisian of that generation".
But the substance was generally neglected in France until the revolution of 1830. In the 1830s there was a surge of interest, and asphalt became widely used "for pavements, flat roofs, and the lining of cisterns, and in England, some use of it had been made of it for similar purposes". Its rise in Europe was "a sudden phenomenon", after natural deposits were found "in France at Osbann (Bas-Rhin), the Parc (Ain) and the Puy-de-la-Poix (Puy-de-Dôme)", although it could also be made artificially.[35] One of the earliest uses in France was the laying of about 24,000 square yards of Seyssel asphalt at the Place de la Concorde in 1835.
Among the earlier uses of bitumen in the United Kingdom was for etching. William Salmon's Polygraphice (1673) provides a recipe for varnish used in etching, consisting of three ounces of virgin wax, two ounces of mastic, and one ounce of asphaltum.[37] By the fifth edition in 1685, he had included more asphaltum recipes from other sources.
The first British patent for the use of asphalt was "Cassell's patent asphalte or bitumen" in 1834.[35] Then on 25 November 1837, Richard Tappin Claridge patented the use of Seyssel asphalt (patent #7849), for use in asphalte pavement,[39][40] having seen it employed in France and Belgium when visiting with Frederick Walter Simms, who worked with him on the introduction of asphalt to Britain.[41][42] Dr T. Lamb Phipson writes that his father, Samuel Ryland Phipson, a friend of Claridge, was also "instrumental in introducing the asphalte pavement (in 1836)".[43] Indeed, mastic pavements had been previously employed at Vauxhall by a competitor of Claridge, but without success.
Claridge obtained a patent in Scotland on 27 March 1838, and obtained a patent in Ireland on 23 April 1838. In 1851, extensions for the 1837 patent and for both 1838 patents were sought by the trustees of a company previously formed by Claridge. Claridge's Patent Asphalte Company—formed in 1838 for the purpose of introducing to Britain "Asphalte in its natural state from the mine at Pyrimont Seysell in France",—"laid one of the first asphalt pavements in Whitehall". Trials were made of the pavement in 1838 on the footway in Whitehall, the stable at Knightsbridge Barracks,"and subsequently on the space at the bottom of the steps leading from Waterloo Place to St. James Park". "The formation in 1838 of Claridge's Patent Asphalte Company (with a distinguished list of aristocratic patrons, and Marc and Isambard Brunel as, respectively, a trustee and consulting engineer), gave an enormous impetus to the development of a British asphalt industry".[45] "By the end of 1838, at least two other companies, Robinson's and the Bastenne company, were in production",[50] with asphalt being laid as paving at Brighton, Herne Bay, Canterbury, Kensington, the Strand, and a large floor area in Bunhill-row, while meantime Claridge's Whitehall paving "continue(d) in good order".
Commercial Paving Contractors in Germiston ?Standard design on a wide median.[1] Stylized depiction of the design in Grand Haven, Michigan, at US 31 and Robbins Road (north to the right), showing the additional area necessary to make a turn on a narrow median.[1] 43°2′40.18″N 86°13′12.57″W / 43.0444944°N 86.2201583°W / 43.0444944; -86.2201583 (US 31 at Robbins Road, Grand Haven, Michigan)
A Michigan left is an at-grade intersection design which replaces each left turn with a U-turn and a right turn. The design was given the name due to its frequent use along roads and highways in the U.S. state of Michigan since the late 1960s.[2] In other contexts, the intersection is called a median U-turn crossover or median U-turn.[1][3] The design is also sometimes referred to as a boulevard left,[4] a boulevard turnaround,[5] a Michigan loon[6] or a "ThrU Turn" intersection.[7][8]Two versions of signs posted along an intersecting road or street at an intersection. Top: most commonly used; Bottom: lesser-used variant.
The design occurs at intersections where at least one road is a divided highway or boulevard, and left turns onto—and usually from—the divided highway are prohibited. In almost every case, the divided highway is multi-laned in both directions. When on the secondary road, drivers are directed to turn right. Within 1⁄4 mile (400 m), they queue into a designated U-turn (or cross-over) lane in the median.
When traffic clears they complete the U-turn and go back through the intersection. Additionally, the U-turn lane is designed for one-way traffic. Similarly, traffic on the divided highway cannot turn left at an intersection with a cross street. Instead, drivers are instructed to "overshoot" the intersection, go through the U-turn lane, come back to the intersection from the opposite direction, and turn right.
When vehicles enter the cross-over area, unless markings on the ground indicate two turning lanes in the cross-over, drivers form one lane. A cross-over with two lanes is designed at high-volume cross-overs, or when the right lane turns onto an intersecting street. In this case, the right lane is reserved for vehicles completing the design. Most crossovers must be made large enough for semi-trailer trucks to complete the crossover. This large cross-over area often leads to two vehicles incorrectly lining up at a single cross-over.
The maneuver forces the driver to quickly merge into the extreme left lane to complete the turn, usually from a complete stop. The turning vehicle is potentially a hazard and may cause a disruption in the flow of traffic in the left lane.[citation needed]
When the median of a road is too narrow to allow for a standard Michigan left maneuver, a variation can be used which widens the pavement in the opposite direction of travel. This widened pavement is known as a "bulb out"[7] or a "loon" (from the pavement's aerial resemblance to the aquatic bird).[6] Such a design is sometimes referred to as a Michigan loon; in Utah, as a ThrU Turn, which is a portmanteau combining the terms "Through" (the intersection, followed by a) "U Turn".[7]
In 2013, Michigan lefts were installed in Alabama for the first time, in several locations along heavily traveled U.S. Route 280 in metro Birmingham.[9]
Tucson, Arizona, began introducing Michigan lefts in 2013, at Ina/Oracle and Grant/Oracle. Their reception has been mixed.[10]
The design is relatively common in New Orleans, Louisiana, and its suburb Metairie, where city boulevards may be split by streetcar tracks,[11] and suburban thoroughfares are often split by drainage canals.[12] Some intersections using this design are signed similarly to those in Michigan, but with more descriptive text,[13] however in some cases the only signage is "No Left Turn" and drivers are left to figure it out for themselves.[14]
Since the redevelopment of the intersection between University Boulevard (MD 193) and Colesville Road (US 29) in Silver Spring, Maryland, a Michigan left has been used to increase efficiency of traffic through an otherwise underdeveloped and congested intersection. Due to its proximity to the Capital Beltway, heavy traffic is handled more safely and efficiently.[citation needed]A typical Michigan left layout: Telegraph Road (US 24) at Warren Road near Detroit, showing Michigan lefts 42°20′28″N 83°16′23″W / 42.341°N 83.273°W / 42.341; -83.273 (US 24 (Telegraph Road) at Warren Road, Dearborn, Michigan)
The Michigan Department of Transportation first used the modern design at the intersection of 8 Mile Road (M-102) and Livernois Avenue[15] (42°26′46″N 83°08′28″W / 42.4461°N 83.141°W / 42.4461; -83.141 (M-102 (8 Mile Road) at Livernois Avenue))[16] in Detroit in the early 1960s. The increase in traffic flow and reduction in accidents was so dramatic (a 30–60% decrease[17]) that over 700 similar intersections have been deployed throughout the state since then.[18]
North Carolina has been implementing Michigan lefts along US 17 in the southeastern part of the state, outside Wilmington.[18] In 2015, a Michigan left was constructed at the intersection of Poplar Tent Road and Derita Road in the Charlotte suburb of Concord.[citation needed]
Columbus, Ohio introduced a Michigan left at the intersection of SR 161 and Strawberry Farms Boulevard in 2012. Reception has been mixed with several accidents occurring per year.[citation needed]
At least two Michigan lefts have existed in Texas. One was located at the intersection of Fondren Road and Bellaire Boulevard in Houston from the 1980s through 2007, when it was replaced with conventional left-turn lanes. Another was built in mid-2010 in Plano at the intersection of Preston Road and Legacy Drive.[19] In January 2014, the city announced plans to revert the turn to a traditional intersection as a result of drivers' confusion.[citation needed] A section of State Highway 71 east of Austin-Bergstrom International Airport at FM 973 in Austin, Texas did have a signalized Michigan U-turn which was constructed in 2014—this was a temporary fix until the SH71 tollway over SH130 (including the re-routing of FM973) was completed in early 2016.[citation needed] There are multiple Michigan left turns currently being used along US 281 north of Loop 1604 in San Antonio. These were adopted as a short-term solution for traffic issues as development expanded north, but will likely be phased out as US 281 is elevated.[citation needed]
The city of Draper, Utah, a suburb of Salt Lake City, announced in 2011 that it would be building Utah's first "ThrU Turn" at the intersection of 12300 South and State Street, just off Interstate 15 through Salt Lake County. Construction began in summer 2011 and was completed in fall 2011.[7][20][21] Other similar intersections were implemented in South Jordan[22] and Layton.[23]
In Australia, where traffic drives on the left, the Victorian state government introduced the "P-turn", similar to the Michigan left, at one intersection in 2009. This requires right-turning vehicles to turn left then make a U-turn. As of May 2015, the intersection in the southeastern Melbourne suburb of Frankston remains the only one of its kind in the state, and local residents have called for its removal.[24]
A similar style P-turn is used in the junction of the A4 Great West Road and A3002 Boston Manor Road in Brentford, England.
The design has been proposed in Toronto, Ontario, to relieve motorists who wish to make a left-turn on roadways which will contain a proposed streetcar line by the Transit City project.
In Ottawa, Ontario, a Michigan left exists to proceed from Riverside Drive, northbound, to Bank Street northbound.
Another Michigan left exists in Windsor, Ontario, on Huron Church Road, just north of the E.C. Row Expressway, where a narrow-median variant put in place years ago is now seldom used due to the realignment of the expressway in conjunction with the construction of the Herb Gray Parkway.
In Mexico, Guadalajara has a grade-separated variation of this setup in the intersection of Mariano Otero Avenue and Manuel Gómez Morín Beltway (20°37′50″N 103°26′06″W / 20.630666°N 103.434981°W / 20.630666; -103.434981).[25] Traffic flowing through Mariano Otero is routed through an overpass above the beltway, with two access roads allowing right turn on all four possible directions; the U-turns, meanwhile, are built underneath the beltway and allow the left turn from Mariano Otero avenue to the beltway. U-turn intersections are very common throughout Mexico, particularly in Mexico City.
Brazil is also known to utilize this setup especially in São Paulo.
This is the design at some busy junctions in Hong Kong. In Hong Kong Island examples include the junction of Fleming Road and Harbour Road in Wan Chai North, and the junction of Hennessey Road and Canal Road Flyover in Wong Nai Chung. In Kowloon this design exists between Cheong Wan Road and Hong Chong Road/Salisbury Road.
The capital city of Angola, Luanda, makes widespread use of a simplified variant of this type of intersection on its two- and three-lane, median-separated throughways instead of using traffic lights. Larger junctions use this intersection type instead of much more costly grade-separated interchanges.
This type of intersection configuration, as with any engineered solution to a traffic problem, carries with it certain advantages and disadvantages and has been subject to several studies.
Studies[by whom?][when?] have shown a major reduction in left-turn collisions and a minor reduction in merging and diverging collisions, due to the shifting of left turns outside the main intersection[clarification needed].[1] In addition, it reduces the number of different traffic light phases, significantly increasing traffic flow. Because separate phases are no longer needed for left turns, this increases green time for through traffic. The effect on turning traffic is mixed.[1] Consequently, the timing of traffic signals along a highway featuring the design is made easier by the elimination of left-turn phases both on that highway and along intersecting roadways contributing to the reduction of travel times and the increased capacity of those roadways.[1]
It has been shown to enhance safety to pedestrians crossing either street at an intersection featuring the design since they only encounter through traffic and vehicles making right turns. The left-turning movement, having been eliminated, removes one source of potential vehicle-pedestrian conflict.[1] One minor disadvantage of the Michigan left is the extra distance required for the motorist to drive. Sometimes the distance to the turnaround is as far away as 1⁄4 mile (400 m) past the intersection. This design leads to each motorist driving an additional 1⁄2 mile (800 m) to make a left turn. It also results in left-turning vehicles having to stop up to three times in the execution of the turn.
Crocodile crackingAsphalt batch mix plant A machine laying asphalt concrete, fed from a dump truck
Asphalt concrete (commonly called asphalt,[1] blacktop, or pavement in North America, and tarmac or bitumen macadam or rolled asphalt in the United Kingdom and the Republic of Ireland) is a composite material commonly used to surface roads, parking lots, airports, as well as the core of embankment dams.[2] It consists of mineral aggregate bound together with asphalt, laid in layers, and compacted. The process was refined and enhanced by Belgian inventor and U.S. immigrant Edward de Smedt.[3]
The terms asphalt (or asphaltic) concrete, bituminous asphalt concrete, and bituminous mixture are typically used only in engineering and construction documents, which define concrete as any composite material composed of mineral aggregate adhered with a binder. The abbreviation, AC, is sometimes used for asphalt concrete but can also denote asphalt content or asphalt cement, referring to the liquid asphalt portion of the composite material.As shown in this cross-section, many older roadways are smoothed by applying a thin layer of asphalt concrete to the existing portland cement concrete, creating a composite pavement.
Mixing of asphalt and aggregate is accomplished in one of several ways:[4]Hot-mix asphalt concrete (commonly abbreviated as HMA) This is produced by heating the asphalt binder to decrease its viscosity, and drying the aggregate to remove moisture from it prior to mixing. Mixing is generally performed with the aggregate at about 300 °F (roughly 150 °C) for virgin asphalt and 330 °F (166 °C) for polymer modified asphalt, and the asphalt cement at 200 °F (95 °C). Paving and compaction must be performed while the asphalt is sufficiently hot. In many countries paving is restricted to summer months because in winter the compacted base will cool the asphalt too much before it is able to be packed to the required density. HMA is the form of asphalt concrete most commonly used on high traffic pavements such as those on major highways, racetracks and airfields. It is also used as an environmental liner for landfills, reservoirs, and fish hatchery ponds.[5] Asphaltic concrete laying machine in operation in Laredo, Texas Warm-mix asphalt concrete (commonly abbreviated as WMA) This is produced by adding either zeolites, waxes, asphalt emulsions, or sometimes even water to the asphalt binder prior to mixing. This allows significantly lower mixing and laying temperatures and results in lower consumption of fossil fuels, thus releasing less carbon dioxide, aerosols and vapors. Not only are working conditions improved, but the lower laying-temperature also leads to more rapid availability of the surface for use, which is important for construction sites with critical time schedules. The usage of these additives in hot mixed asphalt (above) may afford easier compaction and allow cold weather paving or longer hauls. Use of warm mix is rapidly expanding. A survey of US asphalt producers found that nearly 25% of asphalt produced in 2012 was warm mix, a 416% increase since 2009.[6] Cold-mix asphalt concrete This is produced by emulsifying the asphalt in water with (essentially) soap prior to mixing with the aggregate. While in its emulsified state the asphalt is less viscous and the mixture is easy to work and compact. The emulsion will break after enough water evaporates and the cold mix will, ideally, take on the properties of an HMA pavement. Cold mix is commonly used as a patching material and on lesser trafficked service roads. Cut-back asphalt concrete Is a form of cold mix asphalt produced by dissolving the binder in kerosene or another lighter fraction of petroleum prior to mixing with the aggregate. While in its dissolved state the asphalt is less viscous and the mix is easy to work and compact. After the mix is laid down the lighter fraction evaporates. Because of concerns with pollution from the volatile organic compounds in the lighter fraction, cut-back asphalt has been largely replaced by asphalt emulsion.[7] Mastic asphalt concrete, or sheet asphalt This is produced by heating hard grade blown bitumen (i.e., partly oxidised) in a green cooker (mixer) until it has become a viscous liquid after which the aggregate mix is then added. The bitumen aggregate mixture is cooked (matured) for around 6–8 hours and once it is ready the mastic asphalt mixer is transported to the work site where experienced layers empty the mixer and either machine or hand lay the mastic asphalt contents on to the road. Mastic asphalt concrete is generally laid to a thickness of around 3⁄4–1 3⁄16 inches (20–30 mm) for footpath and road applications and around 3⁄8 of an inch (10 mm) for flooring or roof applications. High-modulus asphalt concrete, sometimes referred to by the French-language acronym EMÉ (enrobé à module élevé) This uses a very hard bituminous (penetration 10/20), sometimes modified, in proportions close to 6% on the weight of the aggregates, and a proportion of mineral powder also high, between 8–10%, to create an asphalt concrete layer with a high modulus of elasticity, of the order of 13000 MPa, as well as very high fatigue strengths.[8] High-modulus asphalt layers are used both in reinforcement operations and in the construction of new reinforcements for medium and heavy traffic. In base layers, they tend to exhibit a greater capacity of absorbing tensions and, in general, better fatigue resistance.[9]
In addition to the asphalt and aggregate, additives, such as polymers, and antistripping agents may be added to improve the properties of the final product.
Asphalt concrete pavements—especially those at airfields—are sometimes called tarmac for historical reasons, although they do not contain tar and are not constructed using the macadam process.
A variety of specialty asphalt concrete mixtures have been developed to meet specific needs, such as stone-matrix asphalt, which is designed to ensure a very strong wearing surface, or porous asphalt pavements, which are permeable and allow water to drain through the pavement for controlling stormwater.An airport taxiway, one of the uses of asphalt concrete
Different types of asphalt concrete have different performance characteristics in terms of surface durability, tire wear, braking efficiency and roadway noise. In principle, the determination of appropriate asphalt performance characteristics must take into account the volume of traffic in each vehicle category, and the performance requirements of the friction course. Asphalt concrete generates less roadway noise than a Portland cement concrete surface, and is typically less noisy than chip seal surfaces.[10][11]
Because tire noise is generated through the conversion of kinetic energy to sound waves, more noise is produced as the speed of a vehicle increases. The notion that highway design might take into account acoustical engineering considerations, including the selection of the type of surface paving, arose in the early 1970s.[12][13] With regard to structural performance, the asphalt behaviour depends on a variety of factors including the material, loading and environmental condition. Furthermore, the performance of pavement varies over time. Therefore, the long-term behaviour of asphalt pavement is different from its short-term performance. The LTPP is a research program by the FHWA, which is specifically focusing on long-term pavement behaviour.[14][15]Asphalt damaged by frost heaves
Asphalt deterioration can include crocodile cracking, potholes, upheaval, raveling, bleeding, rutting, shoving, stripping, and grade depressions. In cold climates, frost heaves can crack asphalt even in one winter. Filling the cracks with bitumen is a temporary fix, but only proper compaction and drainage can slow this process.
Factors that cause asphalt concrete to deteriorate over time mostly fall into one of three categories: construction quality, environmental considerations, and traffic loads. Often, damage results from combinations of factors in all three categories.
Construction quality is critical to pavement performance. This includes the construction of utility trenches and appurtenances that are placed in the pavement after construction. Lack of compaction in the surface of the asphalt, especially on the longitudinal joint can reduce the life of a pavement by 30 to 40%. Service trenches in pavements after construction have been said to reduce the life of the pavement by 50%, mainly due to the lack of compaction in the trench, and also because of water intrusion through improperly sealed joints.
Environmental factors include heat and cold, the presence of water in the subbase or subgrade soil underlying the pavement, and frost heaves.
High temperatures soften the asphalt binder, allowing heavy tire loads to deform the pavement into ruts. Paradoxically, high heat and strong sunlight also cause the asphalt to oxidize, becoming stiffer and less resilient, leading to crack formation. Cold temperatures can cause cracks as the asphalt contracts. Cold asphalt is also less resilient and more vulnerable to cracking.
Water trapped under the pavement softens the subbase and subgrade, making the road more vulnerable to traffic loads. Water under the road freezes and expands in cold weather, causing and enlarging cracks. In spring thaw, the ground thaws from the top down, so water is trapped between the pavement above and the still-frozen soil underneath. This layer of saturated soil provides little support for the road above, leading to the formation of potholes. This is more of a problem for silty or clay soils than sandy or gravelly soils. Some jurisdictions pass frost laws to reduce the allowable weight of trucks during the spring thaw season and protect their roads.
The damage a vehicle causes is proportional to the axle load raised to the fourth power,[16] so doubling the weight an axle carries actually causes 16 times as much damage. Wheels cause the road to flex slightly, resulting in fatigue cracking, which often leads to crocodile cracking. Vehicle speed also plays a role. Slowly moving vehicles stress the road over a longer period of time, increasing ruts, cracking, and corrugations in the asphalt pavement.
Other causes of damage include heat damage from vehicle fires, or solvent action from chemical spills.
The life of a road can be prolonged through good design, construction and maintenance practices. During design, engineers measure the traffic on a road, paying special attention to the number and types of trucks. They also evaluate the subsoil to see how much load it can withstand. The pavement and subbase thicknesses are designed to withstand the wheel loads. Sometimes, geogrids are used to reinforce the subbase and further strengthen the roads. Drainage, including ditches, storm drains and underdrains are used to remove water from the roadbed, preventing it from weakening the subbase and subsoil.
Good maintenance practices center on keeping water out of the pavement, subbase and subsoil. Maintaining and cleaning ditches and storm drains will extend the life of the road at low cost. Sealing small cracks with bituminous crack sealer prevents water from enlarging cracks through frost weathering, or percolating down to the subbase and softening it.
For somewhat more distressed roads, a chip seal or similar surface treatment may be applied. As the number, width and length of cracks increases, more intensive repairs are needed. In order of generally increasing expense, these include thin asphalt overlays, multicourse overlays, grinding off the top course and overlaying, in-place recycling, or full-depth reconstruction of the roadway.
It is far less expensive to keep a road in good condition than it is to repair it once it has deteriorated. This is why some agencies place the priority on preventive maintenance of roads in good condition, rather than reconstructing roads in poor condition. Poor roads are upgraded as resources and budget allow. In terms of lifetime cost and long term pavement conditions, this will result in better system performance. Agencies that concentrate on restoring their bad roads often find that by the time they've repaired them all, the roads that were in good condition have deteriorated.[17]
Some agencies use a pavement management system to help prioritize maintenance and repairs.A small-scale asphalt recycler
Asphalt concrete is 100% recyclable and is the most widely reused construction material in the world. Very little asphalt concrete — less than 1 percent, according to a 2011 survey by the Federal Highway Administration and the National Asphalt Pavement Association — is actually disposed of in landfills.[18]
There is asphalt recycling on a large scale (known as in-place asphalt recycling or asphalt recycling performed at a hot mix plant) and asphalt recycling on a smaller scale. For small scale asphalt recycling, the user separates asphalt material into three different categories:Blacktop cookies Chunks of virgin uncompacted hot mix asphalt which can be used for pothole repair. The use of blacktop cookies has been investigated as a less expensive, less labor-intensive, more durable alternative to repairing potholes with cold patch. In a program in Pittsfield, Massachusetts, workers purchased new hot mix asphalt and spread it liberally on the ground to produce approximately 25 lb. wafers. Once cooled, the wafers could be stored until reheated in a hotbox to make minor road repairs. Blacktop cookies may also be produced from leftover material from paving jobs.[19] Reclaimed asphalt pavement (RAP) Chunks of asphalt that have been removed from a road, parking lot or driveway are considered RAP. These chunks of asphalt typically are ripped up when making a routine asphalt repair, man hole repair, catch basin repair or sewer main repair. Because the asphalt has been compacted, RAP is a denser asphalt material and typically takes longer to recycle than blacktop cookies. Asphalt millings Small pieces of asphalt produced by mechanically grinding asphalt surfaces are referred to as asphalt millings. Large millings that have a rich, black tint indicating a high asphalt cement content are best for asphalt recycling purposes. Surface millings are recommended over full depth millings when choosing asphalt millings to recycle. Full depth millings usually contain sub-base contaminants such as gravel, mud and sand. These sub base contaminants will leach oil away from original asphalt and dry out the material in the recycling process. Asphalt milled from asphalt is better than asphalt milled from concrete. When milling asphalt from concrete the dust that is created is not compatible with asphalt products because it is not asphalt.[20]
Small scale asphalt recycling will usually involve high speed on-site asphalt recycling equipment or overnight soft heat asphalt recycling.
Small scale asphalt recycling is used when wanting to make smaller road repairs vs. large scale asphalt recycling which is done for making new asphalt or for tearing up old asphalt and simultaneously recycling / replacing existing asphalt. Recycled asphalt is very effective for pothole and utility cut repairs. The recycled asphalt will generally last as long or longer than the road around it as new asphalt cement has been added back to the material.[21]
For larger scale asphalt recycling, several in-place recycling techniques have been developed to rejuvenate oxidized binders and remove cracking, although the recycled material is generally not very water-tight or smooth and should be overlaid with a new layer of asphalt concrete. Cold in-place recycling mills off the top layers of asphalt concrete and mixes the resulting loose millings with asphalt emulsion. The mixture is then placed back down on the roadway and compacted. The water in the emulsion is allowed to evaporate for a week or so, and new hot-mix asphalt is laid on top.
Asphalt concrete that is removed from a pavement is usually stockpiled for later use as aggregate for new hot mix asphalt at an asphalt plant. This reclaimed material, or RAP, is crushed to a consistent gradation and added to the HMA mixing process. Sometimes waste materials, such as asphalt roofing shingles, crushed glass, or rubber from old tires, are added to asphalt concrete as is the case with rubberized asphalt, but there is a concern that the hybrid material may not be recyclable.


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Politicians and Election, Vote in Freedom, Actively Participate in Democracy, Vote for Change, Online referendum
Civil Force (Hong Kong)
> China > Parties > Civil Force (Hong Kong)
Civil Force (Hong Kong) is ready for your opinion, support and vote. Vote online NOW!
公民力量 - for
公民力量-,香港一個地區組織,主要活躍於新界沙田區和西貢區。 | Civil Force is a community alliance in the Hong Kong Special Administrative Region of the PRC.
公民力量 - against
按一下,如果你不支持他们。 Click, if you do not support the Civil Force. Say why.
civil force, 公民力量, 公民图标, civil force 公民力量, 公民力量 force, civilforce election, 公民力量, 公民力量參選, 公民力量 劉江華 and more...
Related polls > New Century Forum (NCF), Communist Party of China (CPC), Chinese Nationalist Party (KMT), League of Social Democrats, The Frontier (Hong Kong), HK FTU, Southern Democratic Alliance, ADPL (Hong Kong), China Democratic Socialist Party, HK CTU, Civic Party (Hong Kong), Liberal Party (Hong Kong), China Youth League, Democratic Party (DPHK), (Civil Force (Hong Kong)) and more...

subset: commoncrawl


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I recently heard from a homeschooling friend about this site called Code, which encourages people of all ages to learn computer science by completing an "Hour of Code."
Learn the basic concepts of Computer Science with drag and drop programming. This is a game-like, self-directed tutorial starring video lectures by Bill Gates, Mark Zuckerberg, Angry Birds and Plants vs. Zombies. Learn repeat-loops, conditionals, and basic algorithms.
After a busy day of art and parkour classes, jumping on the trampoline, Minecraft, playing and more, my husband Jody and the kids sprawled out in the middle of the living room this evening and started working on it.
Ava was reluctant to start at first, but once she started, she loved it. She's already completed 352 lines of code! After seeing some of her coding in action Ava declared it, "Epic!" She said her favorite part was the drawing.
Julian did about 50 lines of code as well, but wasn't as interested in it at this point as Ava and that's OK. That's the beauty of unschooling. He might want to do it now or later or never at all. He can decide.
I think it's awesome that this free program exists and gives kids as young as six and adults the opportunity to learn how to code. Both of my children are interested in creating mods on Minecraft (their favorite game) and this gives them an idea of what it might be like to do that someday.
If you or your kiddos want to get started learning how to code, check out Learn an Hour of Code: Tutorials for Beginners. I'm excited to get started on it myself as well!
Related posts from around the 'net:


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Blue & Silver Charro Sombrero
$49.95 - $59.95
Item Number: SOM003
Sombreros are an icon of Mexican culture and are perfect for almost any festive occasion. These genuine "Pigalle" sombreros are direct from Mexico and can be used for both formal and party events. These sturdy sombreros are covered in fine felt and stunningly decorated in either silver or gold accents. A chin strap made of decorated string is included to hold the sombrero in place. Don't be fooled by cheap straw imitations! Multiple color and sizeMore…
|by Robert R.; Boca Raton, FL on May 18, 2015


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Panache Restaurant + Lounge
- 50% off
- Only on the App
- Farragut/Dupont
- Tapas Bars, Lounges
Just like the street it sits on, Panache also exudes a NYC vibe–you're more likely to strike up a conversation with a stranger here about what you're drinking than what you do.As soon as we turned the corner to get on Desales Street, which sits horizontally between Connecticut Avenue and 17th Street, just south of M Street, we felt transported. We looked at our bike and said, "Cornelius, we don't think we're in DC anymore." And while you might be shocked 1) that we call our bike Cornelius; and 2) that there's a little NY-style hidden street in the middle of very well-trafficked area of the city, wait 'til you step into Panache, a.k.a. our latest go-to spot for awesomeness.
Just like the street it sits on, Panache also exudes a NY vibe–you're more likely to strike up a conversation with a stranger here about what you're drinking than what you do. We came for a long lunch, complete with a oh-so-summertime-refreshing sangria-tini, which is basically a more booze-laden version of sangria (although you can get that here, too). We sipped it with a few small plates, most notably the prosciutto-wrapped figs. But don't fret if your stomach is as big as your eyes. The Italian chef here also serves up heaping piles of pasta and other lunch specialities. In summary, get here now.
Menu Highlights:
Salmon and Spinach Salad, $13.50
Risotto con Frutti di Mare, $23.95
Prosciutto Wrapped Dates, $7.95
Tortilla Espanola, $7.95
Mozzarella Antipasto, $8.50
Specialty Cocktails, $6 to $10
Tiramisu, $7.50
Monday - Thursday, 11 a.m. to 10 p.m.
Friday, 11 a.m. to 2 a.m.
Saturday, 5 p.m. to 3 a.m.


text: Kristian Slavov wrote: > Manu Abraham wrote: >> Marko Ristola wrote: >> >>> If the current Mantis branch changes would be merged into v4l-dvb, >>> you could concentrate more on other maybe more >>> important projects. You would just sometimes pull >>> v4l-dvb changes into your Mantis branch and if some bug is found in >>> v4l-dvb, >>> you could fix it first into Mantis branch, or then you could send >>> a fix into v4l-dvb directly and pull the changes back. >> Eh ? You wanted to fix INVERSION for the CU1216. This file itself doesn't >> exist in linuxtv.org/hg/v4l-dvb >> >> I don't see your problem, though > > I'm not sure if this is related, but I have both mantis dvb-c pci card and > em2880 based dvb-t usb stick. I would like to get them working at the same time. > Since the mantis branch is probably quite outdated wrt. dvb core, and due to the > recent disagreements between Marcus and some other developers, my problem might > go unsolved for quite some time. > However, if the mantis branch would be closer to the main dvb tree, I might have > a chance to hack the drivers to coexist in my system. > Give me a bit of time Manu


text:
Anthony Wald necesitaba un nuevo diseño de logotipo y lanzó un concurso de diseño en 99designs.
Un ganador ha sido elegido entre 85 diseños de 24 diseñadores freelance.
Remote Rhythm Management Pty Ltd
We are a young company that prides itself in having some of the most experienced cardiac technologist in the field of cardiac rhythm management. Remote management of pacemakers and defibrillators is a paradigm shift in cardiac rhythm management. We are the first national organisation offering a co-ordinated service for both patietns and doctors.
Our target audience is divided into two main areas:
Medical Specialists – doctors (highly educated, astute business people)
The patients – elderly people (not very technologically savvy)
Remote Rhythm Management positions itself as a contemporary company and thus needs a logo to reflect same.
We envision a logo that incorporates the theme of a pacemaker and telemetry, BUT, do not want a plain picture of a pacemaker, antenna and radio waves. The logo needs to reflect the technological advancement in pacemaker programming from office to home.
Due consideration needs to be given to colour palette, font and style as all these elements will flow on to all company collateral.
Descubre cómo funciona un concurso de diseño u obtén más información sobre nuestros servicios de diseño de logo.


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What do they do?
Cracow bakery is one of the few bakeries in and around Greater forex trading
London area that baker an authentic polish bread (brown, crusty skin, generally heavier and thicker than London Bloomer), cakes and polish pastries.
Generally they don't take individual orders, but I am sure you can find their bread and cakes in one of the corner shops near by.
Anything else?
Christmas is coming and Cracow Bakery has a kind of Christmas Specials in their 'menu' First of all it is this chalka cake, which similar to french brioche. Second it's the poppy seed cake and their cheesecakes. Full list of delicacies is available here: http://www.cracowbakery.co.uk/products/cakes. To chcek on full range of products simply visit their website at http://www.cracowbakery.co.uk
If you have a polish friend- get them cakes from Cracow Bakery for Chrismas. They will be delighted!


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Video Startup FlixMaster Lands Funding From Golden Seeds
We tend to think of video on the Web as a fairly linear thing. When a video catches your attention, you may choose to watch it, you may not, or you may watch part of it before your Web-shortened attention span gives out and you're ready to move on to the next thing.
A startup in Colorado called FlixMaster has been challenging that notion with a technology that allows companies to create videos that are more complex and viewer-directed. The company has an API and a cloud-based video editor that can be used to stitch together videos that fork in different directions according to choices the viewer makes.
It's an interesting new way to keep people watching videos for a little longer, and the longer you keep those eyeballs, the more engaged they get with whatever message you're trying to convey, whether it's to sell something or to get them to tune in to something.
FlixMaster is still a relatively small company, but it is punching above its weight in the clients it's landing. HBO has used its platform to create an interactive video for its new Cinemax show, "Banshee." And before that USA Networks used it to promote "Covert Affairs."
Today, FlixMaster says it has landed a new round of funding, its second. The round is $1.125 million, and comes from Golden Seeds, a New York-based investment firm that specializes in early-stage investments in companies run by women.
While media companies present an obvious base of potential customers, enterprises are taking to it in a surprising way. CEO Erika Trautman told me that one company — she declined to name it — uses FlixMaster's technology to produce training videos: Completing one level and passing a test at the end unlocks the next level, and so on. The investment, she said, would help expand sales and marketing efforts targeting enterprise customers.
Trautman also said that FlixMaster is launching some industry-specific modules for editing videos designed for online retailing, corporate customer service and media markets.


text:
See what questions
a doctor would ask.
Cheek itch: A sensation that causes a desire to scratch the skin of the cheek. See detailed information below for a list of 20 causes of Cheek itch, Symptom Checker, including diseases and drug side effect causes.
» Review Causes of Cheek itch: Causes | Symptom Checker »
The following medical conditions are some of the possible
causes of Cheek itch.
There are likely to be other possible causes, so ask your doctor
about your symptoms.
See full list of 20 causes of Cheek itch
» Review Causes of Cheek itch: Causes | Symptom Checker »
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Psoriasis often undiagnosed cause of skin symptoms in children: Children who suffer from the skin disorder called psoriasis can often go undiagnosed. The main problem is that psoriasis is rare in children, and not often seen by physicians for this reason. children...read more »
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The following list of conditions have 'Cheek itch' or similar listed as a symptom in our database. This computer-generated list may be inaccurate or incomplete. Always seek prompt professional medical advice about the cause of any symptom.
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Important:In extreme cases, always seek advice from emergency services :
Medical Conditions associated with Cheek itch:
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Symptoms related to Cheek itch:
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text:
Please check back soon for more information on post-procedure instructions.
Copyright © 2009 Advanced Pediatric Gastroenterolgy. All Rights Reserved.
Home | Meet Dr. Khurana | Medical Services | Library | Patient Resources | About Us | HIPAA/Privacy Policy | Terms & Conditions
Dr. Sanjeev Khurana, MD is a pediatric gastroenterologist serving Phoenix, AZ, Glendale, AZ; Casa Grande, AZ; Surprise, AZ; Tolleson, AZ; and Anthem, AZ; and Goodyear, AZ.


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Although implanting a pacemaker is considered a minor procedure, you will have pre-operative guidelines to follow. Your doctor will provide specific instructions regarding eating and drinking, prior to your procedure. They may also recommend that you stop taking certain medications - like aspirin, which can thin the blood - several hours or days in advance.
Prior to the procedure, you will be required to sign a consent form. As with any procedure, there are risks associated with implanting a pacemaker, including infection, severe bleeding and a collapsed lung. Be sure to discuss these risks or any concerns you may have with your healthcare team.
When you arrive at the hospital, you will dress in a hospital gown and be asked to remove any jewelry or accessories, such as contact lenses or dentures. These will be given to a family member for safe-keeping.
Pacemakers are implanted on either the left or right side of the chest. You will have input as to where it will be best suited for you.
Prior to the procedure, you will be given medications to help relax you. Your chest will be shaved, cleaned, and prepared near the collarbone where the incision will be made.
Although pacemaker procedures may be performed in an operating room, it is not open heart surgery. The procedure is often performed in a cardiac catheterization lab.
You will be conscious during the procedure; however, a local anesthetic will be administered so you will not feel any discomfort. An IV will be started and electrodes will be attached to monitor your heart rhythms during the
The doctor will make an incision about two to four inches long right below the collarbone to create a small pocket. The pacing lead will be threaded through a vein and into your heart. X-ray monitors will guide your physician through the procedure. If a second lead is used, the doctor will repeat the process.
Leads will be tested for sensing and stimulation, and then sewn into the small pocket under the skin. The electrical pacing for your device is then programmed and the incision closed.
Animation Copyright © Milner-Fenwick


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Mike and I both love a big ole' cake, pie or jar full of cookies. His all time favorite is a chocolate cake in an old school 9x13 pan with vanilla buttercream.
The problem is that I work from home.
And most days I work with my computer from the kitchen island (we built ourselves!)... which means that big ole' cake is staring at me all day long. I find myself taking a tiny bite here and there (I'll even keep the fork right in the cake pan - too much work washing all of those forks!). After a couple of days the pan (or cookie jar, or brownie pan) is empty and I am full. Ugh.
But... we really like to have dessert at night when we're winding down in front of the TV. I decided I needed to come up with some mini, individual, easy desserts that I could whip up without making an entire batch.
Keep Reading... Individual Blackberry Crumble Recipe >>
My first solution is an Individual Blackberry Crumble. Not only was it so good - it was healthy, mostly berries with a small amount of crumb topping (about the equivalent of a half of a cookie split between the two of us).
This is also a great dessert to make ahead for a party - you can make individuals or one large pie.
Individual Blackberry Crumble
serves 2
1/2 pint of Blackberries, rinsed
1/4 cup of flour
2+1* tablespoons of sugar
2 tablespoons of brown sugar
1 pinch of cinnamon
1/2 pinch of sea salt
2 tablespoons of butter, cold
*+1 tablespoon of sugar for topping
Place berries in a 4-inch oven-safe ramekin. In a small bowl, mix together dry ingredients with a fork. Using the fork, cut up 2 tablespoons of butter. Put the butter in the bowl with the dry ingredients and begin to incorporate by cutting the butter into the flour mixture. Continue until the butter is the size of peas. Use your hands to crumble the ingredients together. Crumble over the berries. Sprinkle the remaining tablespoon of the sugar over the crumble.
Bake at 350 degrees for 15-20 minutes.
1 bowl + 1 fork
Cut up the butter with a fork. Make sure the butter is cold.
Smash butter into dry ingredients with the fork.
Continue to mix until it looks like this - crumbly.
Crumble it together with your hands.
Sprinkle over the berries.
Top with sugar.
Ice cream highly recommended.


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Visual Acuity on your wrist!
To test your distance vision, use any display in the local wireless as a remote screen.
This app is a joint project between us and Dr. Matthias Hartmann, an ophthalmologist based in Berlin and veteran Apple-enthusiast.
Now with Apple Watch support.iOS Development UX
Started with backwards compatibility to the original iPhone, this was my first iOS project in 2009.
A board game completely in 3D using OpenGL ES, with a challenging AI and unique rule set.
Unfortunately, the multiplayer server is currently offline due to low demand, but as of May 2015 you can download it for free!
(The dev-blog is still available here)
Designed by Viacom, implemented by us, this is the place where your pre-school child can watch & learn!
Featuring friendly colors and lots of multi-touch interactivity, this is an industry standard front-end solution for streaming & downloading videos.
At first glance, this app is just a sales point for Isogon, a Berlin-based company producing high-quality energy-saving windows & doors.
A deeper looks reveals technologically interesting features, such as the ability to measure glass widths with the help of the iPhone's accelerometer, a level-meter, and an energy-savings calculator. What's unique is the ability to preview structured glasses using 3D-scanned meshes that are presented using custom-made OpenGL shaders.
German gamers will know the Game One TV show; we had the opportunity to develop and design the iOS7 version with a completely new look and menu structure.
The original 1.0 version was created by the good people at codenauts.iOS7 Version