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891.
Kang Shi Jing Tang Li Zhang Yong-liang Zhou Dong-sheng Qu Li-Ning Sun Zhong-Qun Tian 《Journal of Solid State Electrochemistry》2005,9(5):398-402
Chemical micro-machining of complex 3-dimensional (3-D) patterns of silicon substrates was preliminarily explored by the confined etchant layer technique (CELT). Through systematic investigation, we demonstrated that cysteine as a scavenger and Br2 as an etchant can be used to etch silicon substrates. The CELT has the potential to develop into a new means of micro-machining complex 3-D patterns on silicon substrates. However, due to the highly corrosive property of the chemicals used for the silicon etched system, great effort must be made to overcome these problems including the mold electrode with high chemical stability.Dedicated to Professor Gygy Horyi on the occasion of his 70th birthday 相似文献
892.
DNA silver staining is widely used to detect DNA fragment in polyacrylamide gel with high sensitivity. Conventional procedures of the silver staining involve several steps, which take about 40 min to 2 h in total. To improve the efficiency of DNA silver staining, a more efficient protocol is developed in this study. The procedure comprises only four steps including impregnating, rinsing, developing, and stopping, and could be completed within 20 min. Nitric acid and ethanol in the silver-impregnation step of the new procedure eliminates the need for prior treatment of gels with a fixing solution and following rinse prior to impregnation with silver. The procedure has high sensitivity and long storage lifetime. The minimum detectable mass of DNA is 0.44 and 3.5 ng in denaturing and nondenaturing polyacrylamide gel, respectively. 相似文献
893.
894.
895.
An analytical method is presented based on reverse isotope dilution single detector inductively coupled plasma magnetic sector mass spectrometry (ID-ICP-SMS) and applied to the specific case of the certification of a (111)Cd enriched candidate Cd spike calibration material (nominal mass fraction 10 mg kg(-1) in 5% HNO3 solution). Uncertainty propagation was used as a tool for both determining the analytical approach and validating it. The robustness of close to "exact matching" reverse IDMS to correction of measured isotope intensities for multiplicative (mass discrimination) and (semi)additive effects (dead time, instrumental background, and isobaric interference) is discussed. The very low experimental relative standard deviation of the mean (0.08%) of eight replicate determinations indicated that all significant sources of uncertainty had probably been taken into account for the estimation of the final combined uncertainty statement (U(c) = 0.17%, k = 1). IRMM-621 was used as comparator. Uncertainties on IUPAC isotopic abundances of 111Cd and 112Cd, for the natural Cd solution involved between the two enriched materials, formed nearly 60% of U(c). The repeatability of the isotope ratio measurements contributed less than 10%. Correction for procedural blank necessitated somewhat unusual calculations (potential contamination of an enriched material with natural Cd). The procedure also involved a quadrupole based ICP-MS judged to be appropriate for the characterization of the isotopic composition. For comparison purposes, direct IDMS results are simulated using identical experimental input data. Finally, a significant background signal in the 106-116 mass region, observed only with the magnetic sector instrument, was attributed to argon based isobaric interferences. 相似文献
896.
离子聚合物在Nylon-1010/PP共混物中的增容作用曲桂杰,刘景江(中国科学院长春应用化学研究所长春130022)关键词聚丙烯,Nylon-1010,离子聚合物,增容选择离子聚合物作为高聚物共混的增容剂,通过离子间的相互作用可达到增容效果[1]。... 相似文献
897.
天然高分子吸附剂研究:Ⅰ.乙二醇双缩水甘油醚交联壳聚糖的制备及其对Cu(? 总被引:15,自引:1,他引:15
报道了乙二醇双缩水甘油醚改性壳聚糖的制备及其对Cu(Ⅱ)、Ni(Ⅱ)的吸附性能,同时考察了PH值、时间、温度等因素对吸附的影响。结果表明,改造后的壳聚糖具有不流失,易再生,在Cu(Ⅱ)、Ni(Ⅱ)共存时能选择吸附Cu(Ⅱ)的特点。 相似文献
898.
YBCO涂层导体CeO2,Y2O3缓冲层的生长研究 总被引:2,自引:1,他引:2
采用反应溅射的方法在具有立方织构的Ni基底上制备了CeO2,Y2O3缓冲层.Ar/H2气氛下预沉积的引入,有效地抑制了基底的氧化.同时,为保证薄膜的外延取向,预沉积时间必须和总沉积时间满足线性关系.对比CeO2,Y2O3的生长条件,发现CeO2的外延生长区间比Y2O3宽,Y2O3的生长对温度、气压等条件更为敏感.最终制备的CeO2缓冲层是纯的(100)取向,其平面内φ扫描半高宽(FWHM)为8.5°;而Y2O3存在两种平面取向,一种是Y2O3(110)‖Ni(100),另一种是Y2O3(100)‖ Ni(100).俄歇能谱观察表明,CeO2/Ni界面优于Y2O3/Ni界面.扫描电镜照片显示,CeO2,Y2O3缓冲层的表面均匀致密,无裂纹生成,但两种薄膜中,都有呈三角形的胞状突起. 相似文献
899.
900.
两种稀土卟啉配合物与大肠杆菌作用的微量热研究 总被引:5,自引:0,他引:5
用LKB-2277生物活性检测系统测定了新合成的阳离子型稀土卟啉配合物{[Re(TMP)(H2O)3]Cl, Re=Y、Yb, TMP=5, 10, 15, 20-四(4’-甲氧基苯基)卟啉}在37 ℃时对大肠杆菌作用的产热曲线,根据产热曲线求算了在稀土卟啉配合物作用下,大肠杆菌生长代谢的速率常数k,抑制率I,传代时间tG和半抑制浓度cI,50等热动力学参数.结果表明,稀土卟啉配合物在低浓度下对大肠杆菌有刺激作用,高浓度下为抑制作用,[Yb(TMP)(H2O)3]Cl的半抑制浓度cI,50为143 mg•L-1,其对大肠杆菌的抑制作用优于[Y(TMP)(H2O)3]Cl. 相似文献