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961.
IntroductionIthasbccndcmonstratcdthatmcthancrcformingt"ithcarbondioxidcpr0ducessynthcsisgasrichincarbonmonoxidc-x"hichisuscfulforthcs}nthcsisofaccticacid'dimcthylcthcrando.o-alcoholsll'2].Carbondioxidcref0rmingismorccndothcrmicthanstcamrcformingfCH4 CO2,'2CO 2H2Ai/'2,,=2473kJ..ol-1(l)Accordingl\"thisrcact1onnccdshighcrtcmpcraturcandlimitsspaccvclocityoffccdgas,Wehavcprct'ious1\studicdmcthancrcformingt"lthC02inthcmonotubcproccssl3J.Inordertoconvcrtmcthancinfccdgascomplctcl}',thcspaccvcloci… 相似文献
962.
研究了熔盐被覆铬碳化物的工艺过程,着重探讨了稀土对T12A钢熔盐渗铬的催渗及微合金化作用机理。结果表明,在加入稀土的熔盐中渗中提高渗速30%-56%,同时还能提高工件表面的抗氧化和耐腐蚀性能以及工件的使用寿命。 相似文献
963.
Zhengbin Zhang Liansheng Liu Hongbin Zhao Youjun Fu Fengyun Cheng Weihong Zhao 《中国科学B辑(英文版)》1997,40(4):353-364
A new method for the study of ternary surface complexes at liquid-solid interface, theE(%) -pH curve method, was proposed. Four types ofE(%)-pH curves, namely, phenomenon of left-right shifts of S-shaped curve, V-shaped curve, monodirection shift curve and X-shaped
curve, were discovered. Correspondingly, apart from type (I) ternary surface complex
and type (II) ternary surface complex
, a new type of ternary surface complex
was discovered.
Project supported by the National Natural Science Foundation of China and the Fund of Doctoral Degree’s Spot. 相似文献
964.
Small gold nanoparticles can mimic dehydrogenase activity to catalyze estradiol (E2) oxidation to estrone (E1), extending the range of nanozyme catalysis to environmentally and biologically important substrates. 相似文献
965.
A novel mode of affinity chromatography (AC) based on an open tubular capillary column (OTAC) is demonstrated. The OTAC column is prepared by immobilizing Cibacron blue F3GA onto the inner surface of a 50-microm-i.d. capillary column. The AC experiment is performed on a capillary electrophoresis instrument by using its pressure system as the driving force. Bovine serum albumin and lysozyme (Lys) are successfully separated with stepwise gradient elution. The relative standard deviation (RSD) for the elution time of the retained Lys is 0.08%, and good repeatability of its peak area and peak height with an RSD value lower than 2.12% for 10 consecutive runs is observed. The loading capacity and detection limit for the retained Lys are approximately 36 ng and 8.6 ng, respectively. It is also found that the amount of protein adsorbed is unaffected by the flow rate of the loading buffer, and OTAC can be used for the fast determination of biopolymers. Some of the advantages of OTAC over conventional modes of open tubular capillary liquid chromatography are that the detection sensitivity and loading capacity of a sample can be greatly improved, because the relatively large inner diameter of the capillary can be adopted and the whole capillary column can be used to adsorb the solute in OTAC. 相似文献
966.
967.
JieLiang Bi-qianLiu 《高分子科学》2005,(1):83-92
Plasma-induced surface graft copolymerization of acrylic acid on polypropylene non-woven fabric (PP-g-AA) and polypropylene membrane were reported. The extents of grafting were controlled by the plasma and polymerization condition. Hexadecyltrimethyl ammonium bromide was then coupled with the carboxyl group of PP-g-AA to obtain a polyion complex (PIC). At last, CF4 plasma was used to give PICs hydrophobic property. The moisture regain and water-repellency of the processed PICs was investigated. The surfaces were characterized using ATR FT-IR and XPS. The result indicates that the products have very high ability to adsorb moisture, even better than cotton fiber. At the same time, the products show excellent hydrophobic property, which can‘t be wetted by those reagents whose surface tensions were higher than 327mN/m. 相似文献
968.
969.
报道了配合物NdI3·C6 H1 2 N4 ·HI·13H2 O的新的合成方法 ,通过元素分析、X射线粉末衍射、红外光谱、核磁共振谱、质谱、差热 热重分析 ,确定了配合物的组成和结构 ,9个水分子与Nd3+ 形成配合阳离子 [Nd(H2 O) 9] 3+ ,C6 H1 2 N4 分子以N原子与Nd3+ 直接作用 ,而 3个I- ,HI以及剩余 4个水分子与配合阳离子 [Nd(H2 O) 9] 3+ 以静电引力或氢键的形式作用。首次测定了配体碘化钕、氢碘酸乌洛托品和配合物对枯草芽孢杆菌、大肠杆菌和葡萄球菌的抗菌活性。所有试样对枯草芽孢杆菌的杀死作用较对葡萄球菌、大肠杆菌的杀死作用显著 ,且高浓度溶液(0 .0 5mol·L - 1 )比低浓度溶液 (0 .0 1mol·L - 1 )的抗菌效果好。浓度为 0 .0 5mol·L - 1时 ,由于协同性 ,配合物NdI3·C6 H1 2 N4 ·HI·13H2 O对枯草芽孢杆菌的杀死作用大于相应的配体 相似文献
970.