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31.
This paper studies a system of partial differential equations modelling the behaviour of a reverse flow reactor. For the parameters appropriate for the oxidation of ammonia on a Pt/Al2O3 catalyst in a typical laboratory set-up, the reactor may be split into regions where approximate formulas that determine its behaviour are deduced. Numerical calculations are presented and can be used to compare with the analytical formulas. The physical insight gained from the asymptotic analysis suggests a new switching strategy which is the subject of numerical experiments. The switching strategy is found to be efficient at minimising the ammonia exiting the reactor after reversal. 相似文献
32.
33.
H Chen M Kalaitsidaki AC Warren D Avramopoulos SE Antonarakis 《Canadian Metallurgical Quarterly》1993,15(3):621-625
PURPOSE: To evaluate the therapeutic effectiveness of a combined chemoradiotherapy program, followed by surgery in selected cases, in Stage III non-small cell lung cancer. METHODS AND MATERIALS: Between August 1988 and February 1990, 43 patients Staged IIIa-b (UICC 1987, 58% IIIb) have been treated with concomitant chemotherapy (cisplatin 15 mg/m2 and VP16 75 mg/m2, 5 days a week on week 1 and 5) and radiotherapy (40 Gy split course, 2 Gy/day on week 1, 2, 5, and 6), followed by attempted curative thoracotomy or more cycles of full dose chemotherapy with the same two drugs. RESULTS: Planned chemoradiotherapy has been given to 91% of patients; 13/43 patients have been operated, with 12 complete resections and three (7%) pathological complete responses. Toxicity was significant, with two postoperative deaths and two fatal radiation pneumonitis. Crude progression-free survival rate is 21% at 30 months, with nine patients (21%) alive and free from progression at follow-up times ranging from 31 to 49 months. Subset survival analysis showed a possibly greater therapeutic effect for non-squamous histology as compared to squamous carcinoma. CONCLUSION: These results are encouraging in a cohort of patients with quite advanced disease (58% Stage IIIb). 相似文献
34.
RW Sidwell DF Smee RP Warren JH Huffman BJ Gilbert RA Burger FC Pearson 《Canadian Metallurgical Quarterly》1993,20(4):279-292
ImuVert, a sterile preparation composed primarily of Serratia marcescens membrane vesicles and ribosomes, was significantly inhibitory to murine cytomegalovirus (MCMV) infections in BALB/c mice. Antiviral activity was manifested as increased survivor number and decreased recoverable virus titers in spleens, lungs and salivary glands. Treatments were intraperitoneal (i.p.) beginning 24 h pre, 4 h post- or 24 h post-virus inoculation and then repeated 4 days later. Doses of 5, 16 or 50 micrograms/mouse were effective; 160 micrograms/mouse, which caused host weight loss in toxicity controls, was not inhibitory to the infection. A single i.p. treatment of mice substantially augmented natural killer (NK) cell activity and increased total B-cells, while reducing total T- and T-helper cells. A late (48 h) decline in T-cell function and transient increases in B-cell function were observed in the treated animals. Serum interferon was not induced. Mice pretreated with anti-asialo GM1 antibody to reduce their NK cell populations, then infected with MCMV and treated with ImuVert were protected to the same degree as normal animals. Severe combined immunodeficient mice infected with MCMV and treated with ImuVert were not protected from the infection. These data suggest ImuVert to act by a mechanism other than NK cell activation in preventing MCMV infections. 相似文献
35.
Warren J. Batchelor Trevor R. Finlayson Anita K. Gross 《Journal of the American Ceramic Society》1993,76(7):1895-1897
The measured plastic deformation of Mg-PSZ under stress contains contributions from both transformation and microcracking. A method is described to separate the contributions from transformation and microcracking for samples deformed in uniaxial tension. Such a separation enables the ratio of the longitudinal to transverse strains arising from the transformation to be estimated. The results are compared to the predictions of the shear–dilatation model of Chen and Reyes-Morel. Serious discrepancies are found between the experimental results and the predictions of the model and the possible reason for this is discussed. 相似文献
36.
Olivier Klein Steve Donovan Martin Dressel George Grüner 《Journal of Infrared, Millimeter and Terahertz Waves》1993,14(12):2423-2457
This report reviews the analysis used to extract the complex conductivity of a compound from a microwave cavity perturbation measurement. We intend to present a generalized treatment valid for any spheroidally shaped sample of arbitrary conductivity which is placed at either the electric or magnetic field antinode of the cavity. To begin with, we establish the relationship between the measured parameters and the conductivity for a spherical sample. Next, we extend these results to the case of spheroids; and for the first time, we cover all different configurations that one can possibly use to study an arbitrary conducting sample inside a cavity: in particular, all possible orientations of the sample with respect to the applied field are solved. 相似文献
37.
Steve Jones 《世界电子元器件》2003,(7):44-46
运行在869MHz-2.17GHz频段内的蜂窝无线基站是射频功率晶体替如今最大的市场。其中,基中硅的LDMOS器件被广泛使用于500MHz=2.5GHz之间的射频功率放大器应用当中。作为增强模式的N沟道MOSFET,LDMOS器件(LD代表侧面扩散,描述了器件的沟道结构)专门被设计成为具有高的工作电压(长沟道)和低寄生电容,从而能在高频下工作。在早 相似文献
38.
Warren Webb 《电子设计技术》2004,11(9):52-60
AdvancedTCA(先进电信计算体系结构)是为下一代电信设备制定的一个有关电路板、背板和软件的新规范.由于具有更大的形状系数、高可用性性能以及高速互连性,AdvancedTCA有可能成为当今专有设备的现成替代品.这一新颖体系结构出现时,电信市场正面临业务与技术的双重挑战. 相似文献
39.
Belli Robert F.; Windschitl Paul D.; McCarthy Thomas T.; Winfrey Steve E. 《Canadian Metallurgical Quarterly》1992,18(2):356
Suggests that detecting memory impairment with the modified test relies on long retention intervals that provide the necessary forgetting of event information for impairing effects of postevent misinformation to occur. 288 Ss were tested in 4 experiments that presented event items centrally, introduced verbal postevent items to a misled condition, and used the modified test, but differed by using either short (15 min) or long (5–7 days) retention intervals. As evidenced by poorer misled than control test performances, memory impairment only occurred with long retention intervals. Retrieval- and storage-based versions of memory-impairment hypotheses are assessed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
40.
Notes that an extensive network of empirical relations has been identified in research on the psychological construct of self-monitoring. Nevertheless, in recent years some concerns have been expressed about the instrument used for the assessment of self-monitoring propensities, the Self-Monitoring Scale (SMS) developed by the 1st author (see record 1975-03047-001). Both the extent to which the SMS taps an interpretable and meaningful causal variable and the extent to which the self-monitoring construct provides an appropriate theoretical understanding of this causal variable have been questioned. An examination of reanalyses of studies of self-monitoring, analyses of the internal structure of the SMS, and further relevant data suggests that the measure does tap a meaningful and interpretable causal variable with pervasive influences on social behavior, a variable reflected as a general self-monitoring factor. The evaluation and furthering of the interpretation of this latent causal variable are discussed, criteria for evaluating alternative measures of self-monitoring are offered, and a new 18-item SMS is presented. (88 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献