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991.
生物质能是一种可再生能源,它来源于生物体(如植物、动物、微生物等)通过光合作用将太阳能转化为化学能,并以有机物的形式储存。生物质能可以在适当的条件下被转化为热能、电能、生物燃料等,是一种重要的替代传统化石能源的可持续能源。生物质气化作为生物质的开发路径之一,是利用生物质生产合成气的有效方式。本文综述了生物质气化技术的研究,包括传统气化技术、共气化技术、化学链气化技术以及超临界气化技术等。介绍了每个气化技术的实验研究,阐述了各个气化技术的特点;详细介绍了化学链气化中载氧体与共气化中掺杂剂的使用。本文旨在探索使生物质气化效率达到最优的方案,并列举了目前存在的局限性,为进一步发展生物质气化技术以及生物质气化研究提供有益参考。 相似文献
992.
LI Bao-sheng LIU Yong ZHAI Yu-feng WANG An 《光电子快报》2006,2(1):75-77
The precise determination of the ZOPDfor the whitelight interferometryis essential toits applicationsinthefield of measurements of surface profile,height ,anddepth,and quality control[1-5].The ZOPDis a positionininterferogram with the highest envelope pea… 相似文献
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994.
Listless zerotree image compression algorithm 总被引:1,自引:0,他引:1
LIAN Jing WANG Ke 《光电子快报》2006,2(5):376-378
Recent years ,wavelet transformhas been widely usedin i mage compression because of its outstanding ti me-frequency localization ability and de-correlation ability.Among all the i mage compression algorithms ,EZW[1]and SPIHT[2]are two of the most influent… 相似文献
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Quasielastic light (QEL) scattering studies of semidilute solutions of polystyrene in benzene and benzene plus diethyl phthalate mixed solvents have been carried out. Comparisons are made between experiment and theoretical results. It is found that the relative amplitude of the viscoelastic modes depends on the coupling parameter β (defined in the text). For the solutions with β=0, no viscoelastic component is observed in the QEL scattering spectrum, consistent with the theoretical prediction. The amplitude and a relaxation time distribution of the viscoelastic component of the QEL scattering spectrum of PS in the mixed solvent are found to depend on time. Steady state values are obtained only after the solution is equilibrated for more than a month. Time evolution of the QEL spectrum has been investigated. 相似文献
998.
John Byrne Steven Hegedus Young-Doo Wang 《Progress in Photovoltaics: Research and Applications》1994,2(3):235-248
For photovoltaic (PV) technology to play an increasing role in the utility sector at its present price, the technology needs to be developed in a manner that is consistent with, and takes advantage of, the economics of the demand-side management (DSM) market. High-value applications in this direction are for photovoltaics to perform a DSM function either as a direct load control (DLC) device or as a peak-shaving option, which has the effect of raising the end-use efficiency of customers' electrical equipment. This paper describes two PV-DSM applications involving a water heater and an air conditioner studied at a residential PV test facility, Solar One House, located on the campus of the University of Delaware. A single 55-W PV module directly connected to an electric water heater was found to offset standby and mixing losses, resulting in a 2°C increase in water temperature at the end of the afternoon compared to the standard DLC (grid-disconnected) case. A conservatively sized PV array without storage could meet the house air-conditioning load over 97% of the time from noon to 3 p.m., but only 69% from 3 p.m. to 6 p.m. If a PV system is combined with an air-conditioning cycling program, success rates for supply of an air-conditioning load are greatly increased, meeting almost 100% of the load between noon and 3 p.m. and 85% during 3 p.m. to 6 p.m. Furthermore, our results suggest that a modest-size PV array with storage could significantly shave peak air-conditioning loads during 3 p.m. to 6 p.m., thus reducing the peak demand faced by a utility. Preliminary analyses support the economic compatibility of a PV system as a DLC device or a peak-shaving tool. 相似文献
999.
Light olefins such as ethylene and propylene are important industrial feedstocks, having essential applications in the production of plastics, ethylbenzene, and... 相似文献
1000.
Kunqian Mu Kaiwen Jiang Yue Wang Zihan Zhao Song Cang Kaishun Bi Qing Li Ran Liu 《Molecules (Basel, Switzerland)》2022,27(3)
β-cyclodextrin has a unique annular hollow ultrastructure that allows encapsulation of various poorly water-soluble drugs in the resulting cavity, thereby increasing drug stability. As a bioactive molecule, the metabolism of β-cyclodextrin is mainly completed by the flora in the colon, which can interact with API. In this study, understanding the in vivo fate of β-cyclodextrin, a LC-MS/MS method was developed to facilitate simultaneous quantitative analysis of pharmaceutical excipient β-cyclodextrin and API dextromethorphan hydrobromide. The established method had been effectively used to study the pharmacokinetics, tissue distribution, excretion, and metabolism of β-cyclodextrin after oral administration in rats. Results showed that β-cyclodextrin was almost wholly removed from rat plasma within 36 h, and high concentrations of β-cyclodextrin distributed hastily to organs with increased blood flow velocities such as the spleen, liver, and kidney after administration. The excretion of intact β-cyclodextrin to urine and feces was lower than the administration dose. It can be speculated that β-cyclodextrin metabolized to maltodextrin, which was further metabolized, absorbed, and eventually discharged in the form of CO2 and H2O. Results proved that β-cyclodextrin, with relative low accumulation in the body, had good safety. The results will assist further study of the design and safety evaluation of adjuvant β-cyclodextrin and promote its clinical development. 相似文献