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31.
32.
丹麦生物质发电的现状和研究发展趋势 总被引:9,自引:7,他引:9
丹麦是世界上利用秸秆生物质燃烧发电技术开发、运行最好的国家,其经验值得中国借鉴。根据作者在丹麦对生物质燃烧发电的研究经历,系统地介绍了丹麦在秸秆生物质发电的经验、遇到的问题及相应的研究和今后的发展方向。 相似文献
33.
T. K. Yurik N. N. Rymar' L. I. Barsova G. N. Pirogova 《Russian Chemical Bulletin》1992,41(9):1531-1536
An investigation was made into the nature of paramagnetic centers in a Tc/Al2O3 system under varying conditions as to heat treatment and technetium content, and in O2 and CO adsorption environments. It was found that in the case of reduction at 573 K Tc2+ ions and, conceivably, other ionic forms developed and stabilized on the carrier surface. After reduction at 973 K two types of electron center appeared, whose concentration increased as reduction was prolonged. Signals were observed in the low fields (3–20 mT) of the ESR spectra having g1 13.5 and g2>30, which could be assigned to free charge carriers in a cluster of metal atoms or ions. Adsorption of O2 at 300 K caused O
2
–
ion radicals to form on the surface of the reduced Tc/Al2O3 samples, both electron centers and technetium ions constituting the electron donors. In the case of CO adsorption paramagnetic (CO)
2
–
particles appeared on the Tc/Al2O3 samples after prolonged exposure. On reaction with O2 two types of O
2
–
ion-radical with differing thermal stability were formed.Institute of Physical Chemistry, Russian Academy of Sciences, Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 1972–1978, September, 1992. 相似文献
34.
The interaction of AlR2(BHT)(OEt2) and AlMe(BHT)2 with methylmethacrylate (MMA) leads to the formation of the Lewis acid-base complexes AlR2(BHT)(MMA) [R = Me (1), Et (2)] and AlMe-(BHT)2(MMA) (3), respectively. The molecular structure of 1 has been determined by X-ray crystallography. The decrease in the C=O and C=C stretching frequencies in the IR spectrum, and downfield shift in the 13C NMR spectrum of the - and γ-carbons of the MMA, when compared to free MMA, is presented with respect to the activator ability of sterically crowded aryloxide compounds of aluminum to aluminum-porphyrin catalyzed (Inoue) polymerization of MMA. 相似文献
35.
近年来化学复合镀技术在工业中应用日益广泛 ,本文运用SEM、AES和XPS等手段对用化学复合镀制得的Ni P PTFE镀层的结构和组分进行了分析 ,并就其耐腐蚀性能与前期得到的Ni Sn P[1 ] 、Cu Sn P[2 ] 、Ni P CeO2 [3] 、Ni P SiO2 [4] 镀层进行了比较 ,结果表明 :含量一定的PTFE(聚四氟乙烯 )的共存增强镀层的耐腐蚀性及镀层表面的润滑性。1 实验部分1 1 仪器日产D/MAXⅢA型X 射线衍射仪 ,铜靶 ,管压 2 5kV ,电流 1 0mA。国产JJC 1型润滑湿角测量仪。美国PERKIN ELMERP… 相似文献
36.
A. I. Sizov T. M. Zvukova A. A. Gorkovskii Z. A. Starikova B. M. Bulychev 《Russian Chemical Bulletin》2004,53(10):2175-2178
The [Cp2HfH2Al(H)Br(OBu)]2 complex (1) was prepared by the reaction of Cp2HfBr2 with AlH3 in THF and characterized by X-ray crystallography. The formation of dinuclear complex 1 proceeds through the intermediate formation (as a result of cleavage of THF molecules) of the >Al(μ-OBu)2Al< fragment. The latter is linked to two hafnocene dihydride molecules by the Hf-H-Al hydrogen bridges. The Hf atom in complex 1 has a 16-electron environment.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2082–2085, October, 2004. 相似文献
37.
对新型的代铬刷镀层Ni-Fe-W-P-S进行了耐腐蚀性能机理的分析研究。用扫描电镜(SEM)、透射电镜(TEM)、扫描隧道显微镜(STM)、X射线衍射及电子能谱(XPS)等的分析表明,基体组织为非品结构是代铬刷镀层优异耐腐蚀性的主要原因. 相似文献
38.
39.
This is the first report on the determination of proteins with tetra-substituted sulphonated aluminum phthalocyanine (AlS4Pc) by resonance light-scattering (RLS). At pH 3.0, the weak RLS of AlS4Pc can be enhanced by the addition of proteins. Based on this, a novel quantitative method has been developed for the determination of proteins in aqueous solutions. Under optimal conditions, the linear ranges of the calibration curves were 0.050–2.0 μg ml−1 for both human serum albumin (HSA) and human r-IgG. The detection limits were 12.7 ng ml−1 for HSA and 16.1 ng ml−1 for human r-IgG. The method has been applied to the analysis of total protein in human serum samples collected from the hospital and the results were in good agreement with those reported by the hospital, which indicates that the method presented here is not only sensitive, simple, but also reliable and suitable for practical applications. 相似文献
40.
反应条件对Cu/Al-Ce-PILC上丙烯选择性催化还原NO反应的影响 总被引:2,自引:0,他引:2
采用聚合羟基复合阳离子合成交联黏土Al-Ce-PILC, 经SO2-4改性后,以浸渍法制备了铜基交联黏土催化剂Cu/Al-Ce-PILC, 并将其应用于C3H6选择性还原NO的反应,考察了预处理气氛、 O2和C3H6浓度、空速、水蒸气和SO2等反应条件对催化剂性能的影响. 结果表明, He预处理后催化剂表面的Cu物种以Cu+和Cu2+两种形式存在,而H2预处理后仅以Cu+存在, NO转化率最大值由23%升至56%. 反应体系中适当的O2和C3H6浓度可促进NO还原为N2, 但过高的浓度反而可降低NO的还原活性, O2同时可起到抑制积炭、清洁催化剂表面的作用. NO转化率随着空速的增大而降低. 10%水蒸气的存在可抑制NO的还原和C3H6的氧化,其转化率曲线向高温方向位移. 但是,由于金属氧化物交联柱表面的疏水特性, Cu/Al-Ce-PILC较Cu/ZSM-5具有较强的耐湿热稳定性, NO和C3H6最大转化率仅分别下降13%和5%. SO2的存在明显抑制了催化剂的低温活性,但对高温活性有一定促进作用. 相似文献