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91.
An efficient and compact catalytic membrane reactor for reforming of CH4 was developed by integrating a hydrogen perm-selective silica membrane with an Rh/-Al2O3 catalyst layer. The catalytic layer was sandwiched between the outer surface of the -Al2O3 support tube and the silica membrane with an aim of improving the heat and mass transfer rates through the system and to simplify the reactor geometry. The system showed improved efficiency for reforming of CH4 at comparatively lower operating temperatures and steam to C molar ratios than the conventional fixed-bed steam reforming systems. Under optimized conditions, a nearly 25-30% improvement from the equilibrium conversion level was achieved as a result of abstraction of hydrogen from the product stream by the silica membrane integrated with the catalyst layer. The performance of the system was evaluated as a function of various process parameters. Because of the compactness and efficiency, the present system emerges as a promising alternative to the conventional membrane reactors, which possess separate catalytic and membrane units. 相似文献
92.
Toshiyuki Yamaguchi Yasutaka AsaiNaoyuki Oku Shigetoshi NiiyamaToshito Imanishi Shigeyuki Nakamura 《Solar Energy Materials & Solar Cells》2011,95(1):274-276
Cu(In,Ga)(S,Se)2 thin films with high Ga/III ratio (around 0.8) were prepared by sequential evaporation from CuGaSe2, CuInSe2, In2Se3 and Ga2Se3 compounds and then annealing in H2S gas atmosphere. The annealing temperature was varied from 400 to 500 °C. These samples were characterized by means of XRF, EPMA, XRD and SEM. The S/(S+Se) mole ratio in the thin films increased with increase in the annealing temperature, keeping the Cu, In and Ga contents nearly constant. The open circuit voltage increased and the short circuit current density decreased with increase in the annealing temperature. The best solar cell using Cu(In,Ga)(S,Se)2 thin film with Ga/(In+Ga)=0.79 and S/(S+Se)=0.11 annealed at 400 °C demonstrated Voc=535 mV, Isc=13.3 mA/cm2, FF=0.61 and efficiency=4.34% without AR-coating. 相似文献
93.
Tamotsu Tanaka Kouji Ikita Tetsuji Ashida Yoshiaki Motoyama Yasunori Yamaguchi Kiyoshi Satouchi 《Lipids》1996,31(11):1173-1178
The effects of growth temperature on the fatty acid compositions of the phosphatidylcholine (PC), phosphatidylethanolamine
(PE), and total lipid (TL) fractions of the free-living nematodeCaenorhabditis elegans were investigated. A reduction in growth temperature from 25 to 15°C caused the proportions of eicosapentaenoic acid (20∶5n-3)
to increase from 23.6 to 32.5% in the PC, from 7.4 to 10.8% in the PE, and from 12.9 to 19.9% in the TL fractions. Conversely,
the levels of dihomo-γ-linolenic acid (20∶3n-6) and arachidonic acid (20∶4n-6) in these phospholipid fractions and the TL
fraction both decreased with decreasing growth temperature. Analysis of the positional distribution of fatty acids in the
PC fraction revealed that the change in the composition of C20 polyunsaturated fatty acid was obvious in positionsn-2. Lowering the growth temperature induced an increase in the level of the diacyl subclass of PE from 58% at 25°C to 71%
at 15°C, with a concomitant decrease in the levels of the alkylacyl and alkenylacyl subclass of PE ofC. elegans. These changes observed in the phospholipids ofC. elegans might be one mechanism for adaptation to low temperature. Lipids 31, 1173–1178 (1996). 相似文献
94.
Imaging of optical disc using reflection-mode scattering-type scanning near-field optical microscopy
Yamaguchi M Sasaki Y Sasaki H Konada T Horikawa Y Ebina A Umezawa T Horiguchi T 《Journal of microscopy》1999,194(PT 2-3):552-557
A phase-change optical disc was observed using a reflection-mode scattering-type scanning near-field optical microscope (RS-SNOM). In an a.c.-mode SNOM image, the 1.2 microm x 0.6 microm recording marks were successfully observed although the data were recorded on the groove. In contrast, no recording marks could be resolved in a d.c.-mode SNOM image. These results are in good agreement with those from a numerical simulation using the finite difference time domain method. The resolution was better than 100 nm with a.c.-mode SNOM operation and the results indicate that recording marks in phase-change optical media can be directly observed with the RS-SNOM. 相似文献
95.
Theasaponin E1 destroys the salt tolerance of yeasts 总被引:1,自引:0,他引:1
Tomita M Yamamoto S Yamaguchi K Ohigashi H Yagi T Kohata K Berden JA 《Journal of Bioscience and Bioengineering》2000,90(6):637-642
Cells of Zygosaccharomyces rouxii in a medium containing a high concentration of NaCl were killed during incubation for 2-4 h with a low concentration of a mixture of saponins from tea seeds (TSS). The higher the concentration of NaCl in the medium, the higher the inhibitory effect of TSS on the growth of the yeast. The above inhibitory effect of TSS on the growth of the yeast was not observed when cells were incubated in hypertonic media composed of nonionic substances such as sugars. The ATPase activity of plasma membrane preparations from the yeast cells was slightly affected by the addition of TSS. It is shown that TSS facilitates leakage of glycerol from the yeast cells under NaCl-hypertonic conditions. The major inhibitor in the mixture of saponins was isolated and identified as theasaponin E1. Its isomer, theasaponin E2, did not have any effect on the salt tolerance of Z. rouxii or Saccharomyces cerevisiae. 相似文献
96.
Processability at extrusion coating and mechanical properties of the films obtained are investigated by means of linear and nonlinear rheological measurements and tensile tests for blends of polypropylene (PP) and linear low‐density polyethylene (LLDPE). Both materials are produced by metallocene catalyst. The processability of PP is found to be improved by the addition of LLDPE; the blend shows low level of motor torque and head pressure in an extruder and small level of neck‐in as compared with pure PP. Further, the anisotropy of ultimate tensile strength, which is prominent for PP, is reduced by blending with LLDPE. As a result, the blend having 20 wt % of LLDPE shows appropriate properties in the molten state for extrusion coating and in the solid state as a film. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
97.
毛细管电泳仪具有灵敏度高、分析速度快等优势,为降低其生产成本,基于电泳原理,以荧光显微镜为基础,设计了一套毛细管电泳系统。以20 bp(base pairs,碱基对)DNA ladder和100 bp DNA ladder为样本,全面分析了系统的稳定性、灵敏度和分离效果。结果表明:该系统在9 min内可以实现1500 bp以内DNA片段的高效分离,系统检测极限为0.1 ng/μL;在优化的电泳条件下,对限制性内切酶φX174-HincⅡ作用过的λ-DNA片段5 min内实现了291 bp与297 bp DNA片段的区分。 相似文献
98.
Yamaguchi T. Uppili S. Lee J.S. Kawamoto G.H. Dosluoglu T. Simpkins S. 《Electron Devices, IEEE Transactions on》1993,40(8):1484-1495
Process and device parameters are characterized in detail for a 30-GHz f T submicrometer double poly-Si bipolar technology using a BF2-implanted base with a rapid thermal annealing (RTA) process. Temperature ramping during the emitter poly-Si film deposition process minimizes interfacial oxide film growth. An emitter RTA process at 1050°C for 30 s is required to achieve an acceptable emitter-base junction leakage current with an emitter resistance of 6.7×10-7 Ω-cm2, while achieving an emitter junction depth of 50 nm with a base width of 82 nm. The primary transistor parameters and the tradeoffs between cutoff frequency and collector-to-emitter breakdown voltage are characterized as functions of base implant dose, pedestal collector implant dose, link-base implant dose, and epitaxial-layer thickness. Transistor geometry dependences of device characteristics are also studied. Based on the characterization results for poly-Si resistors, boron-doped p-type poly-Si resistors show significantly better performance in temperature coefficient and linearity than arsenic-doped n-type poly-Si resistors 相似文献
99.
100.
In the present work, the increase in the basicity index of the slag system of the flux, represented by the ternary system of MnO–SiO2–CaO oxides, is evaluated. The increment of the basicity index is performed by the addition of CaO, keeping the MnO/SiO2 percentage relation of the system constant, in order to evaluate the behaviour of the chemical composition resulting from the metal deposited by SAW. As a result, it is possible to intensify the Mn transfer to the deposited metal and at the same time attenuate that of the Si, S, P and the carbon remains basically unalterable. All this makes it possible, in combination with low-manganese wire, to obtain similar results to those obtained with fluxes of lower basicity in combination with medium manganese wires. 相似文献