Concurrent

Around 2000, the regulations should become more severe. In this area, a European limit of benzene of 3% appears very probable certain countries such as Germany are even looking at 1%. In Italy, it was decided towards the end of 1991, to limit benzene to 2.5% for leaded and unleaded fuels in the seven largest cities characterized by having heavy atmospheric pollution concurrently, in these same cities, the overall aromatic contents of gasolines should not exceed 33%. 

Product quality specification Contractual agreements Capacity and availability Concurrent operations Monitoring and control Testing metering Standardisation Flaring and venting Waste disposal Utilities systems... 

Fig.3. The piston s castings are tested on surfaces A, B by using the two pair of transducers worked in separate-concurrent regime.

Rettner C T 1994 Reaction of an H-atom beam with Cl/Au(111)—dynamics of concurrent Eley-Rideal and Langmuir-Hinshelwood mechanisms J. Chem. Phys. 101 1529... 

Factors other tlian tire Si/Al ratio are also important. The alkali-fonn of zeolites, for instance, is per se not susceptible to hydrolysis of tire Al-0 bond by steam or acid attack. The concurrent ion exchange for protons, however, creates Bronsted acid sites whose AlO tetraliedron can be hydrolysed (e.g. leading to complete dissolution of NaA zeolite in acidic aqueous solutions). 

As noted above, one of the goals of NAMD 2 is to take advantage of clusters of symmetric multiprocessor workstations and other non-uniform memory access platforms. This can be achieved in the current design by allowing multiple compute objects to run concurrently on different processors via kernel-level threads. Because compute objects interact in a controlled manner with patches, access controls need only be applied to a small number of structures such as force and energy accumulators. A shared memory environment will therefore contribute almost no parallel overhead and generate communication equal to that of a single-processor node. 

The primary developers of NAMD 1 were M. Nelson, W. Humphrey, A. Gursoy, A. Dalke and R. Brunner. The primary developers of NAMD 2 were J. Phillips, A. Shinozaki, R. Brunner, N. Krawetz, M. Bhandarkar and A. Gursoy. NAMD development was performed at the National Institutes of Health Resource for Concurrent Biological Computing under the supervision of principal investigators L.V. Kale, R. Skeel, and K. Schulten. This work was... 

Kale, L., Krishnan, S. Charm-t—1- A Portable Concurrent Object Oriented System Based on C-(—1-. In Proceedings of the Conference on Object Oriented Programming Systems, Languages and Applications. A. Paepcke, editor. ACM Press, New York, N.Y., 1993. 

Concurrently with the preparation of the phenyldiazonium chloride solution, prepare a cold suspension of sodium arsenite. Place 250 ml. of water in a 3-htre round-bottomed flask equipped with a mechanical stirrer. Heat the water to boding, add 125 g. of anhydrous sodium carbonate, and, as soon as the carbonate has dissolved, introduce 62 5 g. of pure arsenious oxide and 3 g. of crystallised copper sulphate with stirring. When all the solids have dissolved, cool the solution with stirring under a stream of tap water until the temperature has fallen to 15°. 

Matrix QMC procedures, similar to configuration interaction treatments, have been devised in an attempt to calculate many states concurrently. These methods are not yet well developed, as evidenced by oscillatory behavior in the excited-state energies. 

One route to 0-vinyl derivatives involves LiPdCl4-calalysed exchange with vinyl acetate[l]. Rearrangement and cyclization occur concurrently to give 1-acylindoles. 

By having a large number of point ion collectors in a line in a plane, many different m/z values can be recorded at the same bme (concurrently rather than sequentially, as with a single-point ion collector). 

One drawback of time bins relates to the events they record. If two or more ions arrive at the array detector at the same instant, the resulting electrical pulse is the same as if only one ion had arrived. The bins are blind to multiple concurrent events. 

Mineralocorticoids foUow a mechanistic route similar to that of glucocorticoids, though differing in the proteins expressed. The activated MR-DNA complex promotes the expression of aldosterone-induced proteins (AIPs), which then act to increase conductance of the luminal membrane and concurrently increase pump activity of the basolateral membrane. These actions result from a number of AlP-influenced cellular characteristics,... 

The selective addition of the second HCN to provide ADN requires the concurrent isomerisation of 3PN to 4-pentenenitrile [592-51 -8] 4PN (eq. 5), and HCN addition to 4PN (eq. 6). A Lewis acid promoter is added to control selectivity and increase rate in these latter steps. Temperatures in the second addition are significandy lower and practical rates may be achieved above 20°C at atmospheric pressure. A key to the success of this homogeneous catalytic process is the abiUty to recover the nickel catalyst from product mixture by extraction with a hydrocarbon solvent. 2-Methylglutaronitrile [4553-62-2] MGN, ethylsuccinonitfile [17611-82-4] ESN, and 2-pentenenitrile [25899-50-7] 2PN, are by-products of this process and are separated from adiponitrile by distillation. 

The price of acetaldehyde duriag the period 1950 to 1973 ranged from 0.20 to 0.22/kg. Increased prices for hydrocarbon cracking feedstocks beginning in late 1973 resulted in higher costs for ethylene and concurrent higher costs for acetaldehyde. The posted prices for acetaldehyde were 0.26/kg in 1974, 0.78/kg in 1985, and 0.92/kg in 1988. The future of acetaldehyde growth appears to depend on the development of a lower cost production process based on synthesis gas and an increase in demand for processes based on acetaldehyde activation techniques and peracetic acid. 

Other Separations. Other TSA appHcations range from CO2 removal to hydrocarbon separations, and include removal of air poUutants and odors, and purification of streams containing HCl and boron compounds. Because of their high selectivity for CO2 and their abiHty to dry concurrently,... 

The heated polymer solution emerges as filaments from the spinneret into a column of warm air. Instantaneous loss of solvent from the surface of the filament causes a soHd skin to form over the stiU-Hquid interior. As the filament is heated by the warm air, more solvent evaporates. More than 80% of the solvent can be removed during a brief residence time of less than 1 s in the hot air column. The air column or cabinet height is 2—8 m, depending on the extent of drying required and the extmsion speed. The air flow may be concurrent or countercurrent to the direction of fiber movement. The fiber properties are contingent on the solvent-removal rate, and precise air flow and temperature control are necessary. 

The single-step -duoroaruline [31-40-4] process based on duorodeoxygenation of nitrobenzene (via in situ generation of /V-phenylhydroxyl amine) in anhydrous hydrogen duoride (94—96) has not been commercialized primarily due to concurrent formation of aniline, as well as limited catalyst life. The potential attractiveness of this approach is evidenced by numerous patents (97—101). Concurrent interest has been shown in the two-step process based on /V-phenylhydroxylamine (HF-Bamberger reaction) (102—104). 

PVF is more thermally stable than other vinyl halide polymers. High molecular weight PVF is reported to degrade in an inert atmosphere, with concurrent HF loss and backbone cleavage occurring at about 450°C (71,72). In air, HF loss occurs at about 350°C, followed by backbone cleavage around 450°C. 

Of the water-soluble vitamins, intakes of nicotinic acid [59-67-6] on the order of 10 to 30 times the recommended daily allowance (RE)A) have been shown to cause flushing, headache, nausea, and moderate lowering of semm cholesterol with concurrent increases in semm glucose. Toxic levels of foHc acid [59-30-3] are ca 20 mg/d in infants, and probably approach 400 mg/d in adults. The body seems able to tolerate very large intakes of ascorbic acid [50-81-7] (vitamin C) without iH effect, but levels in excess of 9 g/d have been reported to cause increases in urinary oxaHc acid excretion. Urinary and blood uric acid also rise as a result of high intakes of ascorbic acid, and these factors may increase the tendency for formation of kidney or bladder stones. AH other water-soluble vitamins possess an even wider margin of safety and present no practical problem (82). 

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