全文获取类型
收费全文 | 64篇 |
免费 | 7篇 |
国内免费 | 15篇 |
专业分类
化学 | 59篇 |
晶体学 | 1篇 |
力学 | 3篇 |
综合类 | 2篇 |
数学 | 7篇 |
物理学 | 14篇 |
出版年
2024年 | 1篇 |
2023年 | 3篇 |
2022年 | 10篇 |
2021年 | 4篇 |
2020年 | 3篇 |
2019年 | 10篇 |
2018年 | 4篇 |
2016年 | 4篇 |
2015年 | 5篇 |
2014年 | 4篇 |
2013年 | 2篇 |
2012年 | 5篇 |
2011年 | 2篇 |
2010年 | 2篇 |
2009年 | 4篇 |
2008年 | 2篇 |
2007年 | 4篇 |
2006年 | 4篇 |
2005年 | 2篇 |
2002年 | 1篇 |
1999年 | 2篇 |
1993年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1959年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有86条查询结果,搜索用时 0 毫秒
81.
用魔芋多糖(KGM)和N,N-二甲基甲酰胺(DMF)的加合物,将肌红蛋白(Mb)固定在玻碳电极(GCE)上,制备了稳定的Mb-KGM-DMF/GCE修饰电极,并研究了Mb在修饰电极上的直接电化学行为和电催化性能。该电极在pH=7.0的磷酸盐缓冲溶液(PBS)中,-0.38 V(E0′)处有一对氧化还原峰,峰电位差ΔEp=70 mV,该峰正是Mb中血红素辅基FeⅢ/FeⅡ电对的氧化还原特征峰。在0.2~9.0 V/s扫速的范围内,氧化还原峰峰电流大小和扫描速率成正比,呈现出表面控制行为。在pH为5.0~12.0的范围内,式电位和pH值呈线性关系,表明电子传递过程伴随着质子转移。同时,Mb-KGM-DMF/GCE修饰电极表现出良好的电催化性能,对氧、H2O2有显著的催化作用。在4.70~75.0μmol/L的范围内,其催化峰电流大小与H2O2的浓度有良好的线性关系,其线性回归方程i=0.127 0.093C,r=0.9989,表观米氏常数为80.8μmol/L。 相似文献
82.
Kaan Atak Ozgur O. Aybar Gokhan ?ahin Avadis Hac?nl?yan Yani Skarlatos 《Central European Journal of Physics》2009,7(3):568-574
Polyethylene Glycol has an irregular current characteristic under constant voltage and slowly varying relative humidity. The
current through a thin film of Gamma-isocyanatopropyltriethoxysilane added Polyethylene glycol (PEG-Si), its hydrogenated
and hydrophobically modified forms, as a function of increasing relative humidity at equal time steps is analyzed for chaoticity.
We suggest that the irregular behavior of current through PEG-Si thin films as a function of increasing relative humidity
could best be analyzed for chaoticity using both time series analysis and detrended uctuation analysis; the relative humidity
is kept as a slowly varying parameter. The presence of more then one regime is suggested by the calculation of the maximal
Lyapunov exponents. Furthermore, the maximal Lyapunov exponent in each of the regimes was positive, thus confirming the presence
of low dimensional chaos. DFA also confirms the presence of at least two different regimes, in agreement with the behavior
of the maximal Lyapunov exponent in the time series analysis. We also suggest that the irregular behavior of the current through
PEG-Si can be reduced by hydrogenating and hydrophobically modifying PEG-Si and the improvement in stability can be confirmed
by our study.
相似文献
83.
Prof. Chunshan Lu Xuejie Zhang Yani Qi Haoke Ji Qianwen Zhu Hao Wang Yebin Zhou Zhenlong Feng Prof. Xiaonian Li 《ChemistryOpen》2019,8(1):87-96
A nitrogen-carbon framework with the thickness of several molecules was fabricated through a straightforward nitrogen-doping strategy, in which specially designed surface-oxygen-containing groups (SOGs) first introduced onto the porous carbon support were used to guide the generation of a surface-nitrogen-containing structure through condensation reactions between SOGs and the amidogen group of organic amines under hydrothermal conditions. The results indicate that different kinds of SOGs generate different types and abundances of N species. The CO-releasing groups are apt to form a high proportion of amino groups, whereas the CO2-releasing groups, especially carboxyl and lactones, are mainly transformed into pyrrolic-type nitrogen. In the framework with dominant pyrrolic-type nitrogen, an electron-rich Pd activated site composed of Pd, pyrrolic-type N and C is built, in which electron transfer occurs from N to C and Pd atoms. This activated site contributes to the formation of electron-rich activated hydrogen and desorption of p-chloroaniline, which work together to achieve the superior selectivity about 99.90 % of p-chloroaniline and the excellent reusable performance. This strategy not only provides low-cost, nitrogen-doped carbon materials, but also develops a new method for the fabrication of different kinds of nitrogen species structures. 相似文献
84.
Sans résumé
Presented by J. D. Monk. 相似文献
85.
Shuming Dou Jie Xu Danfeng Zhang Wen Liu Cuihua Zeng Jiangchao Zhang Zhedong Liu Haoqiang Wang Yani Liu Yu Wang Yanbing He Wei-Di Liu Wei Gan Yanan Chen Qunhui Yuan 《Angewandte Chemie (International ed. in English)》2023,62(26):e202303600
Bimetallic alloy nanomaterials are promising anode materials for potassium-ion batteries (KIBs) due to their high electrochemical performance. The most well-adopted fabrication method for bimetallic alloy nanomaterials is tube furnace annealing (TFA) synthesis, which can hardly satisfy the trade-off among granularity, dispersity and grain coarsening due to mutual constraints. Herein, we report a facile, scalable and ultrafast high-temperature radiation (HTR) method for the fabrication of a library of ultrafine bimetallic alloys with narrow size distribution (≈10–20 nm), uniform dispersion and high loading. The metal-anchor containing heteroatoms (i.e., O and N), ultrarapid heating/cooling rate (≈103 K s−1) and super-short heating duration (several seconds) synergistically contribute to the successful synthesis of small-sized alloy anodes. As a proof-of-concept demonstration, the as-prepared BiSb-HTR anode shows ultrahigh stability indicated by negligible degradation after 800 cycles. The in situ X-ray diffraction reveals the K+ storage mechanism of BiSb-HTR. This study can shed light on the new, rapid and scalable nanomanufacturing of high-quality bimetallic alloys toward extended applications of energy storage, energy conversion and electrocatalysis. 相似文献
86.
The host–guest inclusion mechanism formed between β-cyclodextrin and those poorly water-soluble drug molecules has important applications in supramolecular chemistry, biology and pharmacy. In this work, the chiral recognition ability of β-cyclodextrin to one of nonsteroidal anti-inflammatory drugs, ketoprofen, has been systematically investigated using molecular dynamics and free energy simulation methods. The R- and S-enantiomers of ketoprofen were explicitly bound within the cyclodextrin cavity in our simulations, respectively. In consistent with experimental observations, tiny structural difference between two isomers could be observed. Calculated absolute binding free energies using adapted biasing force (ABF) method and MM/GBSA approach for both isomers are comparable to experimental values. Significant binding fluctuations along the MD trajectory have been observed. The free energy profiles calculated using two different approaches reveal that the ketoprofen prefers binding in the cavity with the carboxylate group facing the wider edge of β-cyclodextrin. Similar free energy profiles for two enantiomers obtained using ABF calculations indicate that it is very hard to separate and identify the chiral conjugates within the framework of the natural β-cyclodextrin. 相似文献