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81.
溶胶-凝胶技术制备高效液相色谱氧化锆填料   总被引:5,自引:4,他引:5  
Zhang Q  Feng Y  Da S 《色谱》1999,17(3):284-286
 以氧氯化锆水解得到溶胶,然后以Span-80和Tween-85混合非离子表面活性剂为乳化剂、环己烷为有机相制成W/O型乳状液,用其控制粒度,可得到2~10μm的ZrO2凝胶微球。通过比表面积、孔容、孔径测试及对6种不同性质的物质的吸附试验表明,该微球产物可作为高效液相色谱填料。  相似文献   
82.
The preparation and characterization of the 1:1 inclusion compound of rhodium(II) -methyl cinnamate in -cyclodextrin is reported. Evidence of inclusion was obtained from X-ray powder diffraction results, Raman, IR and UV-Vis spectroscopic studies and thermal analysis. Given the potential antitumor activity of the rhodium(II) carboxylate and its virtual insolubility in water, its inclusion in -cyclodextrin opens the possibility for its transference to the aqueous phase.  相似文献   
83.
84.
Neon-like niobium X-ray lasers have been studied using both slab and thin-foil target geometries. Niobium foils of various lengths were irradiated from both sides with two beams of the frequency-doubled Nova laser system using a line focus. We looked for gain by measuring spectrally integrated line intensities at different plasma lengths. Gain was observed in four neon-like niobium lines corresponding to 3s–3p transitions. The line profile of theJ = 0–1 line ( = 145.9 ) shows splitting due to the hyperfine effect. Improved contrast in the hyperfine structure is observed as the plasma length is increased. Hyperfine splitting may be relevant to other 3s–3p transitions in neon-like niobium as well as other neon-like X-ray laser systems.  相似文献   
85.
神经网络在橡胶硫化温度预测中的应用   总被引:7,自引:1,他引:6  
本文针对难以通过在线测温实现等效硫化控制的情况,在确定硫化条件的直接测温实验基础上,提出了用神经网络模型预测实际生产过程中硫化制品内部温度的方法.在该方法中将所测温度值作为样本提供给神经网络学习,温度采集时刻及易测外部温度作为网络输入,输出值则是在硫化时制品难测温点处不同时刻的内温.神经网络通过学习取得了良好的效果,网络输出的温度值将成为等效硫化计算和硫化质量智能控制的有价值的依据.  相似文献   
86.
Treatment of a THF solution of trans-[ReCl(N2)(dppe)2] (dppe = Ph2PCH2CH2PPh2) with a 1-alkyne HCCR (R =tBu, CO2Me, CO2Et, or C6H4Me-4), in the presence of Tl[BF4]/[NH4][BF4], under sunlight, affords the corresponding carbyne-fluoro complexes trans-[ReF(CCH2R)(dppe)2][BF4] in an unprecedented single-pot synthesis. Further reaction with [BU4N]OH leads to the vinylidenefluoro compounds trans-[ReF(=C=CHR)(dppe)2] (R = CO2Me, CO2Et, or C6H4Me-4).  相似文献   
87.
Polysubstituted benzene derivatives were synthesized starting from the Baylis-Hillman adducts via the sequential introduction of primary nitroalkane at the primary position, Michael addition to β-branched Michael acceptor, aldol condensation, elimination of nitrous acid, and the final aromatization process.  相似文献   
88.
A pilot-scale sewage treatment system consisting of two upflow anaerobic sludge bed (UASB) reactors followed by five waste stabilization ponds (WSPs) in series was studied under subtropical conditions. The first UASB reactor started up in only 1 mo (stable operation, high chemical oxygen demand [COD] removal efficiency, low volatile fatty acids concentration in the effluent, alkalinity ratio above 0.7, biogas production above 0.1 Nm3/kg of CODremoved). Removal efficiencies up to 90% were obtained in the anaerobic steps at a hydraulic retention time of 6 + 4 h (80% removal in the first step). Fecal coliform removal in the whole system was 99.9999% (99.94% in anaerobic steps and 99.98% in WSPs). COD balances over UASB reactors are provided. A minimum set of data necessary to build COD balances is proposed. Intermittent sludge washout was detected in the reactors with the COD balances. Sludge washout from single-step UASB reactors should be monitored and minimized in order to ensure constant compliance with discharge standards, especially when no posttreatment is provided. The system combined high COD and fecal coliform removal efficiency with an extremely low effluent concentration, complying with discharge standards, and making it an attractive option for sewage treatment in subtropical regions.  相似文献   
89.
The use of supercritical fluids (SCFs) as solvents has been attracting widespread interest in the research and commercial applications. The study of partial molar volumes of solutes at infinite dilution in the near-critical region is of considerable fundamental importance, as these data reflects the interactions occurring between the solute and the solvent. Experimental measurements of partial molar volumes may be divided into two categories: direct and indirect methods. The direct methods…  相似文献   
90.
Monoclonal antibody technique was employed to detect the conformational difference of CaM induced by metal ions. A trivalent europium ion induced conformation-specific anti-calmodulin monoclonal antibody was successfully prepared with europium-saturated calmodulin as antigen.  相似文献   
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