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1.
光谱学研究血卟啉与鲱鱼精DNA的相互作用   总被引:3,自引:0,他引:3  
以中性红(NR)作探针研究了血卟啉(HD)与DNA的相互作用.光谱学研究表明,血卟啉与DNA发生作用生成了超分子复合物.其结合比nHD:nDNA=3:1,血卟啉与DNA的结合常数K=1.84×104L/mol.同时运用Scatchart方程研究了血卟啉与DNA的作用方式,确定了血卟啉与鲱鱼精DNA之间的作用方式为混合作用方式.其作用机理可能是血卟啉以部分插入方式同时伴随共价和静电方式与DNA作用,影响其基因调控与表达,进而抑制肿瘤细胞的生长.  相似文献
2.
二对硝基苯酯与β-环糊精相互作用的光谱学研究   总被引:1,自引:0,他引:1  
以二环己基碳二亚胺(DCC)为脱水剂,使有关脂肪族二酸与对硝基苯酚缩合,合成了丁二酸二对硝基苯酯、己二酸二对硝基苯酯和癸二酸二对硝基苯酯等3种具有不同长度碳链的二酸二对硝基苯酯。利用红外光谱、质子核磁共振、元素分析、差示扫描量热等手段确证了酯的组成和结构。在此基础上以荧光猝灭、荧光光谱、紫外-可见光谱等技术系统研究了3种二酯与β-环糊精(β-CD)之间的主客体相互作用。结果表明:随二酯中二酸碳链增长,二酯与β-CD发生主客体作用的难度增加。实验条件下,丁二酸二对硝基苯酯分子中两个对硝基苯基结构均可进入β-CD疏水内腔,己二酸二对硝基苯酯分子中只有一个对硝基苯基结构可以进入β-CD疏水内腔,而癸二酸二对硝基苯酯分子中的两个对硝基苯基结构都不能进入β-CD疏水内腔,这种现象产生的原因可能是由于3种二酯在水溶液中采取了不同的构象。因此,碳链较短的二酸二对硝基苯酯可能比较适合于构筑基于主客体相互作用的三维网状结构。  相似文献
3.
流动注射化学发光法测定山奈酚   总被引:1,自引:0,他引:1  
采用流动注射技术,研究了高锰酸钾-山奈酚-过氧化氢体系的化学发光行为,对影响化学发光强度的因素进行了试验,建立了流动注射化学发光法测定山奈酚的新方法。方法检出限为1×1-0 10g.mL-1,线性范围为1.0×10-7—1.0×1-0 4g.mL-1。对1.0×1-0 6g.mL-1的山奈酚平行测定11次,其RSD为2.1%。该方法用于三叶青中山奈酚含量的测定,结果令人满意。  相似文献
4.
共振瑞利散射光谱法测定人体血浆和尿液中的加替沙星   总被引:1,自引:0,他引:1  
韩权  王媚  田丽  杨娜 《光谱实验室》2010,27(6):2146-2150
提出了共振瑞利散射光谱法测定加替沙星的新方法。在pH5.2~5.6的Britton—Robinson缓冲溶液中,加替沙星(Gatifloxaein,GTFX)与钻(Ⅱ)能形成阳离子配合物,它可进一步与酸性染料刚果红(CR)阴离子反应形成2:1:1(GTFX:Co2+:CR)的三元离子缔合物,使共振瑞利散射(RRS)急剧增强。其2个散射峰分别位于382nm和560nm处。在382nm处,加替沙星的浓度在0-5.26ug·mL-1范围内,与RRS强度有良好的线性关系,检出限(3a)为7.5ng·mL-1。此方法简便、快速,且具有良好的选择性,用于片剂、尿液和血浆中加替沙星的测定,其回收率在96.1%-103.6%。  相似文献
5.
康丽君  徐强 《光谱实验室》2009,26(3):745-748
制备了水杨酸功能化聚苯乙烯包覆硅胶复合微粒,填充微柱后,测定了微柱的穿透曲线和洗脱曲线。将微柱用于低浓度Ag(I)的分离富集测定,研究了各影响因素,优化了实验条件。测定Ag(I)的线性范围为0.020—0.50μg/mL。方法可用于水样中痕量银的测定。  相似文献
6.
在碱性条件下,以混合模板剂pH调节水热合成了掺入铈的介孔分子筛Ce-MCM-48,并采用XRD,DRUV-Vis(紫外-可见漫反射),FTIR,XRF结合BET等测试手段对样品进行表征.实验结果表明,采用本方法所合成的掺铈介孔材料仍保持立方介孔的有序结构,同时适量的铈的掺入和pH调节使分子筛的有序性及吸附性能得到改善,晶胞参数增大,孔径更均一,孔壁增厚.从而可推出Ce-MCM-48的热稳定性、水热稳定性、催化活性及择形选择性可得到提高.掺入的铈以四配位状态高度分散在介孔的有序结构当中.红外光谱表明不同量的铈的掺入对骨架硅的各种振动扰动程度不同.  相似文献
7.
利用罗丹明B(RhB)-H2O2化学发光体系及流动注射技术,研究了十二烷基磺酸钠(SDS)存在下,氯化血红素在紫外光下的光解反应动力学规律,并与不加入SDS时氯化血红素光解行为进行了对比.结果表明:SDS存在与否,氯化血红素的光解行为均符合一级动力学反应方程.但是加入SDS后所形成的胶束相,减缓了氯化血红素的光解速度,提高了其光稳定性.  相似文献
8.
TiO2 nanoparticles capped with sodium dodecylbenzenesulfonate (DBS) are synthesized by a sol-hydrothermal process using tetrabutyl titanate and DBS as raw materials. The effects of surface-capping DBS on the surface photovoltage spectroscopy (SPS), photoluminescence (PL) and photocatalytic performance of TiO2 nanoparticles are principally investigated together with their relationships. The results show that the surface of TiO2 nanoparticles can be well capped by DBS groups while the pH value and added DBS amount are controlled at 5.0 and 2% of TiO2 mass weight, respectively, and the linkage between DBS groups and TiO2 surfaces is mainly by means of quasi-sulphonate bond. The intensities of SPS and PL spectra of TiO2 obviously decrease after DBS-capping, while the activity can greatly increase during the photocatalytic degradation of Rhodamine B (RhB) solution, which are mainly attributed to the electron-withdrawing character of the DBS groups. Moreover, the enhancement of photocatalytic activity of DBS-capped TiO2 is also related to the increase in the capability for adsorbing RhB.  相似文献
9.
FexPt100−x(30 nm) and [FexPt100−x(3 nm)/ZrO2]10 (x = 37, 48, 57, 63, 69) films with different ZrO2 content were prepared by RF magnetron sputtering technique, then were annealed at 550 °C for 30 min. This work investigates the effect of ZrO2 doping on the microstructural evolution, magnetic properties, grain size, as well as the ordering kinetics of FePt alloy films. The as-deposited films behaved a disordered state, and the ordered L10 structure was obtained by post-annealing. The magnetic properties of the films are changed from soft magnetism to hard magnetism after annealing. The variation of the largest coercivities of [FexPt100−x/ZrO2]10 films with the Fe atomic percentage, x and differing amounts of ZrO2 content reveals that as we increase the ZrO2 content we must correspondingly increase the amount of Fe. This phenomenon suggests that the Zr or O atoms of ZrO2 preferentially react with the Fe atoms of FePt alloy to form compounds. In addition, introducing the nonmagnetic ZrO2 can reduce the intergrain exchange interactions of the FePt/ZrO2 films, and the interactions are decreased as the ZrO2 content increases, the dipole interactions are observed in FePt/ZrO2 films as the ZrO2 content is more than 15%.  相似文献
10.
A novel photo-luminescence film has been prepared by immobilizing pyrene on a quartz plate surface via diethylenetriamine. Imino structure was intentionally introduced into the long flexible spacer due to their hydrogen bond forming abilities with carboxylic acids. It has been found that the film shows combined monomer and excimer emission of pyrene both in wet and dry states. Steady-state and time-resolved fluorescence emission measurements demonstrated that the excimer emission mainly came from direct excitation of ground state dimers, and/or monomers in aggregated state. The structures of the excimers formed during the excitation are mixtures of “standard excimers” and “distorted excimers” of the fluorophore moieties. Fluorescence lifetime measurements showed that the decay of the film is complex, and a four exponential fit is necessary for getting a satisfied result. The photophysical behavior of the present film could be rationalized by employing the model proposed before. Sensing property studies showed that the emission of the film is sensitive to the presence of dicarboxylic acids, including ethanedioic acid, malonic acid, etc. In contrast, presence of monocarboxylic acids, such as formic acid and acetic acid, had little effect upon the fluorescence emission of the film. Compared with the films taking ethylenediamine or 1,3-diaminopropane as their spacer component, introduction of diethylenetriamine into the spacer improved the performance of the film greatly. In addition, the sensing process is reversible, and the film is stable within a number of months provided it is properly preserved. These characteristics showed that the film is worthwhile for further exploration.  相似文献
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