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961.
962.
研究了B2O3和CaF2对C3S-C2.75B1.25A3S珚-C2S-C3A熟料矿物体系的组成、结构与力学性能的影响。研究结果表明:在该熟料体系中C3S,C2.75B1.25A3S珔,C2S和C3A的适宜含量分别为50%,10%,25%和15%,B2O3和CaF2的适宜掺量为2%和1.5%。在最佳组成和制备工艺条件下,合成的阿利特-硫铝酸钡钙水泥的1d,3d和28d抗压强度分别达到18MPa,48MPa和95MPa以上,展现了良好的早期力学性能。同时,掺加CaF2能有效降低熟料中游离氧化钙的含量,促进阿利特在低温条件下形成。利用SEM-EDS,XRD等测试手段对熟料的组成、结构及性能进行了分析。 相似文献
963.
964.
SBR反应器中反硝化条件下去除苯酚工艺 总被引:2,自引:0,他引:2
基于异养反硝化原理,在序批式间歇反应器(SBR)中对反硝化同时降解苯酚的菌种进行了149 d的驯化,驯化通过逐步提高进水中苯酚和NO3--N的浓度进行.驯化结束后,进水苯酚质量浓度达到360 mg/L,葡萄糖质量浓度达到100 mg/L,NO3--N质量浓度达到240 mg/L,水力停留时间6 h,苯酚和NO3--N去除率均大于98%.反应器运行结果表明:进水苯酚质量浓度低于720 mg/L时,SBR反应器运行稳定;高浓度NO2--N(>60 mg/L)可以严重影响微生物对苯酚以及NO3--N的去除能力,同时反应器中20.5%~23.5%的COD可被用于微生物的细胞合成. 相似文献
965.
Host Plant Volatiles Synergize Response to Sex Pheromone in Codling Moth, Cydia pomonella 总被引:1,自引:0,他引:1
Plant volatile compounds synergize attraction of codling moth males Cydia pomonella to sex pheromone (E,E)-8,10-dodecadien-1-ol (codlemone). Several apple volatiles, known to elicit a strong antennal response, were tested in a wind tunnel. Two-component blends of 1 pg/min codlemone and 100 pg/min of either racemic linalool, (E)-beta-farnesene, or (Z)-3-hexen-1-ol attracted significantly more males to the source than codlemone alone (60, 58, 56, and 37%, respectively). In comparison, a blend of codlemone and a known pheromone synergist, dodecanol, attracted 56% of the males tested. Blends of pheromone and plant volatiles in a 1:100 ratio attracted more males than 1:1 or 1:10,000 blends. Adding two or four of the most active plant compounds to codlemone did not enhance attraction over blends of codlemone plus single-plant compounds. Of the test compounds, only farnesol was attractive by itself; at a release rate of 10,000 pg/min, 16% of the males arrived at the source. However, attraction to a 1:10,000 blend of codlemone and farnesol (42%) was not significantly different from attraction to codlemone alone (37%). In contrast, a codlemone mimic, (E)-10-dodecadien-1-ol, which attracted 2% males by itself, had a strong antagonistic effect when blended in a 1:10,000 ratio with codlemone. 相似文献
966.
967.
968.
Faliang Zhang Yongchun Luo Anqiang Deng Zhaohui Tang Long Kang Jianhong Chen 《Electrochimica acta》2006,52(1):24-32
(La, Ce, Pr, Nd)2MgNi9 hydrogen storage alloys were prepared through induction melting followed by a long annealing treatment. The structure and electrochemical properties of annealed alloys have been investigated by orthogonal design experiments. Both the individual effects of each substituting element and their interaction in alloys were studied systemically. It has been shown that the structure of main phase in alloys belongs to PuNi3-type with a space group R-3m. Substituting rare-earth elements have a significant effect on both the phase structure of alloys and microstructure. The anisotropic change in the crystal structure of alloys can cause the acceleration of pulverization of alloy particles and result in the deterioration of the cyclic stability of alloy electrodes. Misch metals can raise the plateau pressure of hydrogen absorption/desorption. The discharge capacity of alloy ranges from 342.97 to 380.68 mAh g−1 depending on the sort and content of substituting elements. Both cerium and neodymium can obviously reduce the discharge capacity of alloy electrodes. When compared to the La2MgNi9 alloy electrode, mish metals can significantly improve the high rate dischargeability of alloy electrodes. The improvement of the kinetic characteristic of alloy electrodes mainly results from the increase of the hydrogen diffusion rate in alloy bulk. 相似文献
969.
A. Galal 《应用聚合物科学杂志》2006,102(3):2416-2425
Poly(3‐methlthiophene) films were prepared under “silent” and “sono‐electrochemical” potentiostatic (SEP) conditions. A three‐electrode one‐compartment sono‐cell was used with a working platinum disc electrode. The sono‐electrochemically formed polymer films were deposited with different working electrode‐to‐horn distances. The composition, electrochemical, spectroscopic, and morphological characteristics of the resulting polymer films were determined. Elemental analysis, FTIR‐spectra, and X‐ray photoelectron spectroscopy (XPS) data proved that the polymer films prepared under SEP conditions have predominant α‐α′‐couplings between the 3MT units, and the aromatic ring integrity is maintained in the film. Scanning electron microscopy showed that those films are more compact and less porous compared to the films prepared under silent conditions. The use of sono‐irradiation during electropolymerization enhanced the diffusion of the monomer units towards the electrode surface and resulted in relatively less doped polymers with less conductivity. Electrochemical impedance spectroscopy (EIS) data for films prepared under silent and SEP conditions were collected in a monomer‐free solution. The results show that the impedance of SEP films is relatively higher than those prepared under silent conditions, and a combination of charge transfer kinetics with diffusion‐controlled conduction mechanism within the films. The diffusion was found to be a function of the porosity of the film. Conductivity measurements are in good agreement with EIS, elemental analysis, and XPS data. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2416–2425, 2006 相似文献
970.
阳离子香豆胶的合成及结构表征 总被引:1,自引:1,他引:1
以3-氯-2-羟丙基三甲基氯化铵(HAT)为阳离子醚化剂,天然香豆胶为原料,异丙醇为分散剂制得季铵盐型阳离子香豆胶。研究了HAT、催化剂NaOH、反应温度和反应时间对合成阳离子香豆胶(CFG)的影响,用凯氏定氮法测定了CFG的取代度。合成CFG的优化实验条件为:m(香豆胶)∶m(异丙醇)∶m(HAT)∶m(NaOH)=1∶(1.6~2)∶(0.15~0.3)(∶4~8),反应温度40~50℃,反应时间2~3 h,制得的产品能满足工业应用要求的黏度及取代度范围(500~800 mPa.s,DS=0.86~1.32)。用FTIR和13CNMR对CFG的结构进行了表征。 相似文献