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851.
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The solubilitices of benzene, toluene and diphenyl in mixed solvents of t-butyl alcohol (TBA) and water at 283.15, 288.15, 293.15 and 298.15 K have been determined by spectrophotometry. The mole fraction of TBA [x (TBA)] in the mixed solvent are 0.000, 0.010, 0.020, 0.030, 0.040, 0.045, 0.050, 0.060, 0.080 and 0.100, respectively. The standard Gibbs energies of solution of benzene, toluene and diphenyl in the mixed solvent have also been calculated based on the solubility data. The hydrophobic interactions (HI) for the pairs of benzene-benzene, methane-benzene and methane-methane in the mixed solvent were calculated and discussed. 相似文献
853.
B. Zhou S. Jiang L. Zou X. Wang D. Wang J. Liu S. Shang D. Zhou 《Journal of Thermal Analysis and Calorimetry》1999,58(2):487-493
A new compound cyclohexyl-t-butyldimethylammonium tetraphenylborate, [C6H11N(CH3)2(C(CH3)3)]BPh4 has been prepared, and its decomposition mechanism was studied by TG. The IR spectra of the products of thermal decomposition were examined at every stage. Kinetic analysis for the first stage of thermal decomposition process was obtained by TG and DTG curves, and kinetic parameters were obtained from the analysis of the TG-DTG curves with integral and differential equations. The most probable kinetic function was suggested by comparison of kinetic parameters.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
854.
Dongmei Zhou Hanfa Zou Jianyi Ni Hailin Wang Li Yang Yukui Zhang 《Chromatographia》1999,50(1-2):27-34
Summary Affinity columns suitable for HPLC were prepared by immobilization of various ligands of protein A, human IgG, human IgM and
pectinase on GMA modified cellulose membrane. The adsorption capacity, affinity efficiency and activity recovery of various
IgGs on these affinity columns were measured. It was observed that the length of the coupling arm plays a very important role
in affinity efficiency, and the effect of eluent flow-rate on adsorption capacity was very small. The protein A column was
exploited for the process monitoring of dog IgG in clinical experiments on immuno-adsorption therapy. A pectinase column was
used for the determination of polygalacturonase inhibiting proteins first purified on a hydroxyapatite column. It took only
about 2.5 min for analysis at a flow-rate of 1.0 mL min−1. The high speed analysis of biopolymers could be performed at a flow rate of 6.0 mL min−1 within 15 s. Membrane affinity chromatography gives good reproducibility, high efficiency, low column-pressure and is rapid.
It can also be used for micro-scale purification of biopolymers. 相似文献
855.
烟煤与重质油共处理的研究 总被引:4,自引:0,他引:4
煤与重质油的共处理是最有希望实现“由煤制油”的第三代煤液化新工艺之一。我国目前炼油厂每年有四、五千万吨石油渣油产出,只有一小部分用作制氢或合成气的生产原料以及生产沥青或石油焦,其余大部分用于工业燃料[1]。如将减压渣油与煤进行共处理,共同提质,提高其... 相似文献
856.
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859.
Formation and crystal structure of metallic inclusions in a HPHT as-grown diamond single crystal 总被引:2,自引:0,他引:2
L.-W. Yin N.-W. Wang Z.-D. Zou M.-S. Li D.-S. Sun P.-Z. Zheng Z.-Y. Yao 《Applied Physics A: Materials Science & Processing》2000,71(4):473-476
One of the most important characteristics associated with crystal growth technology is the entrapment of inclusions by the
growing crystal. Diamond single crystals prepared under high temperature-high pressure (HPHT) usually contain metallic inclusions.
In the present paper, metallic inclusions in a diamond grown from a Fe-Ni-C system using the HPHT method have been, for the
first time, systematically examined by transmission electron microscopy (TEM). Energy dispersive X-ray spectrometry (EDS)
, combined with selected area electron diffraction (SAD) patterns, has been used to identify the chemical composition and
crystal structure of the metallic inclusions. The metallic inclusions were found to be composed mainly of cubic γ-(FeNi),
face-centered cubic (FeNi)23C6, ortho-rhombic Fe3C and hexagonal Ni3C, which may have been formed through the entrapment of molten catalyst by the growth front or through reaction of the trapped
melt with contaminants in the diamond.
Received: 19 June 2000 / Accepted: 21 June 2000 / Published online: 16 August 2000 相似文献
860.