Parallel channel

By far the most abundant phosphate mineral is apatite, which accounts for more than 95% of all P in the Earth s crust. The basic composition of apatite is listed in Table 14-2. Apatite exhibits a hexagonal crystal structure with long open channels parallel to the c-axis. In its pure form, F , OH , or Cl occupies sites along this axis to form fluorapatite, hydroxyapatite, or chlor-apatite, respectively. However, because of the "open" nature of the apatite crystal lattice, many minor substitutions are possible and "pure" forms of apatite as depicted by the general formula in Table 14-2 are rarely found. 

Selective oxidation of p-xylene was carried out over the temperature range of 450-590°C at an atmospheric pressure using an 8-channel parallel tubular reactor system made in-... 

Figure 5.9 Structure of silicon viewed down [110]. The atoms are drawn smaller than the atomic radius suggests for clarity. Channels parallel to <110> facilitate interstitial diffusion in this material.

The two major approaches for HPLC purification are fast gradient separation and parallel purification. Yan et al.178 utilized the former (Figure 1.51). The purification lab received a 96-well plate containing synthesized products at 0.1 to 0.2 mmol/well. A Hydra 96-probe liquid handler prepared QC plates for all samples that were analyzed with a MUX-LCT eight-channel parallel LCMS instrument at a throughput of 2000 samples/day. Only samples with purities above 10% were purified on a... 

The C=C double bond in [XCF=CFBF3] is more easily accessible to oxidation (fluorine addition) than that of XCF=CFBF2 (28). The oxidation is initiated by polarized XeF2, formed in a channel parallel to the xenodeborylation, by the interaction of XeF2 and the strong Lewis acid, XCF=CFBF2 (eq 8). 

Dow Plastics is to unveil a new resilient polyolefin foam, Strandfoam, which offers packagers of lightweight electronic equipment and components reduced package size, and savings in materials and shipping costs. Strandfoam is made of a special blend of PE and is produced by a proprietary extrusion process that yields fused strands of closed-cell foam with a network of air channels parallel to the foam strands. Strandfoam provides the required levels of protection with substantially smaller volumes of foam compared to urethane. 

Among eight Be-containing minerals in the BeO-Al Og-SiO -H O system, beryl has the widest stable range (=siOkbar, 320 —680 °C) [2], and exhibits a relatively stable Habitus bounded by 0001 and [1010] faces crystals showing spear-shaped tapered forms, or crystals containing channels parallel to the c-axis. 

A complete 3D structure of Ni(DPG)2I has been published and this shows a tetragonal space group with stacks of Ni(DPG)2 units staggered by 90°. The iodine species are located in channels parallel to the Ni(DPG)2 stacks.97 The presence of I5 ions has been identified from resonance... 

We have optimized an eight-way MUX coupled to a TOFMS analyzer to carry out eight-channel parallel LC/UV/MS analysis of combinatorial libraries14 in the past 2 years. This system has not only provided the capacity needed for library analysis, but also enabled simultaneous evaluation of experimental parameters to expedite the method development process. In this chapter, we discuss the optimization of this system and present a high-throughput protocol for combinatorial library analysis. We also compare the eight-channel parallel LC/UV/MS system to a conventional single channel LC/UV/MS system in terms of performance and operation. 

The j -Si3N4 structure exhibits channels parallel to the c-axis which are about 0.5 nm in diameter causing the relative high diffusion coefficient compared to a which do not show such channels (Table 1). These channels are changed into voids with seven nearest nitrogen neighbours in the a structure. 

Acrylonitrile is commercially produced from propylene by a molybdate-based catalyst that has been optimized to produce a yield of around 80% acrylonitrile. Utilizing a less-expensive feedstock, the selective ammoxidation of propane to acrylonitrile has significant potential in reducing acrylonitrile production cost. The work-flow for this chemistry consisted of a primary scale evaporative synthesis station and 256-channel parallel screening reactor using a proprietary optical-based detection method. For the initial work shown here, secondary screening was done on a six-channel fixed-bed reactor. 

Fig. 10.6 Scheme of a 16-channel parallel prototype reactor jointly developed with AMTEC GmbH company, now commercialised as SWITCH 16" reactor. See http //www.amtec-chemnitz.be. 

Fig. 11.9 Photograph of a 16-channel parallel rotating disk electrode (PRDE) test station for high-throughput screening of high surface-area carbon-supported electrocatalysts. The PRDE station is part of the secondary screening workflow for electrocatalysts.

Feng, B. McQueney, M. S. Mezzasalma, T. M. Slemmon, J. R. 2001. An integrated ten-pump, eight-channel parallel LC/MS system for automated high-throughput analysis of proteins. Anal. Chem, 73, 5691-5697. 

We have seen how the screw extruder pump is synthesized from a simple building block of two parallel plates in relative motion. We have also seen how the analysis of the screw extruder leads in first approximation back to the shallow channel parallel plate model. We carried out the analysis for isothermal flow of a Newtonian fluid, reaching a model (Eq. 6.3-27) that is satisfactory for gaining a deeper insight into the pressurization and flow mechanisms in the screw extruder, and also for first-order approximations of the pumping performance of screw extruders. 

The above requirements are to some extent contradictory, which has led to the proposition of a large number of different catalyst shapes and arrangements. However, only a few of these have proved really effective in practical operation. Suitable catalyst forms and arrangements include random packings of spheres, solid cylinders, and hollow cylinders, as well as uniformly structured catalyst packings in the form of monoliths with parallel channels, parallel stacked plates, and crossed, corrugated-plate packets (Fig. 3). 

Figure 5. Stereoview of the refined positions of one TPAF complex and Its relation to the surrounding portion of the silica framework and end C atoms of adjacent complexes. The N atom lies near the origin of the four arrows at the upper left of Figure 4, and the C8 and C9 atoms lie nearly in the center of a straight channel parallel to b. The C1-C6 atoms lie in a mirror plane and the C1-C3 and C4-C6 limbs point along adjacent zig and zag portions of a zigzag channel. (Reproduced from Ref. 4. Copyright 1982, American Chemical Society.)...

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