全文获取类型
收费全文 | 215篇 |
免费 | 10篇 |
国内免费 | 1篇 |
专业分类
化学 | 120篇 |
晶体学 | 6篇 |
力学 | 3篇 |
数学 | 22篇 |
物理学 | 75篇 |
出版年
2022年 | 1篇 |
2021年 | 1篇 |
2020年 | 3篇 |
2019年 | 1篇 |
2017年 | 1篇 |
2016年 | 3篇 |
2015年 | 4篇 |
2014年 | 2篇 |
2013年 | 7篇 |
2012年 | 15篇 |
2011年 | 10篇 |
2010年 | 10篇 |
2009年 | 20篇 |
2008年 | 10篇 |
2007年 | 8篇 |
2006年 | 19篇 |
2005年 | 6篇 |
2004年 | 11篇 |
2003年 | 6篇 |
2002年 | 12篇 |
2001年 | 4篇 |
2000年 | 8篇 |
1999年 | 7篇 |
1998年 | 3篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 6篇 |
1993年 | 3篇 |
1992年 | 8篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 4篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1978年 | 2篇 |
1976年 | 2篇 |
1975年 | 2篇 |
排序方式: 共有226条查询结果,搜索用时 15 毫秒
81.
The quadratic performance measure of estimation errors in approximated by using the Legendre polynomial approach for the design of optimal observers with specified distinct and multiple eigenvalues. This method is simple as compared with other design techniques of optimal observers. One example is illustrated, and only a small number (m=6) of shifted Legendre series are needed to produce a much better result than that obtained by the convenient block-pulse function. 相似文献
82.
Lin LC Meng HF Shy JT Horng SF Yu LS Chen CH Liaw HH Huang CC Peng KY Chen SA 《Physical review letters》2003,90(3):036601
The triplet to singlet exciton formation ratio in a MEH-PPV light-emitting diode is measured by comparing the triplet-induced absorptions with optical and electric excitations at the same singlet exciton density. The ratio is a strong universal decreasing function of the averaged electric field. Using 4 ns for singlet to triplet intersystem crossing time, the ratio is significantly larger than the spin-independent value 3 at intermediate field but is reduced to about 2 for higher field. 相似文献
83.
Pannuru Pavani Gupta Bhupender S. Horng Jia-Cherng Lee Ming-Jer 《Journal of Thermal Analysis and Calorimetry》2020,142(5):2003-2013
Journal of Thermal Analysis and Calorimetry - To elucidate the influence of commonly used biological buffers on the hemoglobin (Hb) structure, biomolecular interactions between Hb and the selected... 相似文献
84.
Crystal Structure Analysis of the Repair of Iron Centers Protein YtfE and Its Interaction with NO
下载免费PDF全文
![点击此处可从《Chemistry (Weinheim an der Bergstrasse, Germany)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Dr. Feng‐Chun Lo Chang‐Chih Hsieh Dr. Manuel Maestre‐Reyna Prof. Chin‐Yu Chen Dr. Tzu‐Ping Ko Prof. Yih‐Chern Horng Yei‐Chen Lai Prof. Yun‐Wei Chiang Chih‐Mao Chou Cheng‐Hung Chiang Prof. Wei‐Ning Huang Dr. Yi‐Hung Lin Prof. D. Scott Bohle Prof. Wen‐Feng Liaw 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(28):9768-9776
Molecular mechanisms underlying the repair of nitrosylated [Fe–S] clusters by the microbial protein YtfE remain poorly understood. The X‐ray crystal structure of YtfE, in combination with EPR, magnetic circular dichroism (MCD), UV, and 17O‐labeling electron spin echo envelope modulation measurements, show that each iron of the oxo‐bridged FeII–FeIII diiron core is coordinatively unsaturated with each iron bound to two bridging carboxylates and two terminal histidines in addition to an oxo‐bridge. Structural analysis reveals that there are two solvent‐accessible tunnels, both of which converge to the diiron center and are critical for capturing substrates. The reactivity of the reduced‐form FeII–FeII YtfE toward nitric oxide demonstrates that the prerequisite for N2O production requires the two iron sites to be nitrosylated simultaneously. Specifically, the nitrosylation of the two iron sites prior to their reductive coupling to produce N2O is cooperative. This result suggests that, in addition to any repair of iron centers (RIC) activity, YtfE acts as an NO‐trapping scavenger to promote the NO to N2O transformation under low NO flux, which precedes nitrosative stress. 相似文献
85.
S.Y. Yang J.J. ChiehW.C. Wang C.Y. YuN.S. Hing H.E. Horng Chin-Yih Hong H.C. Yang C.F. ChangH.Y. Lin 《Journal of magnetism and magnetic materials》2011,323(6):681-685
In this work, we investigate the feasibility of detecting quantitatively DNA molecules utilizing the technology named after the immunomagnetic reduction (IMR) assay. Magnetic nanoparticles dispersed in a phosphate buffer saline solution were bio-functionalized with probing single-strand DNA. A superconducting quantum interference device (SQUID) ac magnetosusceptometer was employed to detect IMR signals related to the concentration of the target DNA. The results reveal that use of IMR assay had merits such as a high convenience level, e.g. wash-free processes and high sensitivity, down to pM, for DNA detection. 相似文献
86.
Yi-Hao Huang Yet-Pole I Nan-Chi Chen Sheng-Hung Wu Jao-Jia Horng Yung-Tin Wu I-Jyh Wen 《Journal of Thermal Analysis and Calorimetry》2013,113(2):595-598
Benzoyl peroxide (BPO) has been used as initiator or medicine in the chemical industries. Several thermal runaway reactions, fires, and explosions have occurred in Taiwan due to its thermal reactivity and explosive properties. A serious accident was analyzed occurring at Fu-Kao Chemical Plant in Taiwan because of runaway reaction in a batch reactor including methyl acrylate (MA), acrylic acid (AA), and BPO. This accident resulted in one death and more than 100 injuries. Differential scanning calorimetry and thermogravimetry (TG) were used to investigate and calculate the thermal hazard and safety parameter of BPO. Finally, the effects of MA and AA mixed with BPO by DSC/TG were analyzed in this study. The T 0 of BPO was 109 °C in this study. Therefore, the T 0 of BPO/MA was calculated to be 105 °C by DSC. AA and MA were identified as catalyst for thermal decomposition of BPO. 相似文献
87.
In this study, we found that the double metal contact structure in Pt/Al/n-InP diodes provides better rectification characteristics than conventional single-metal/n-InP Schottky diodes. The effective barrier height was measured to be 0.67 eV for a 400 °C-annealed Pt/Al/n-InP diode sample. The increase in the barrier height is attributed to the formation of Al2O3 at the metal/n-InP contact interface during thermal annealing. The formation of the phase Al2O3 phase was monitored by X-ray diffraction (XRD) analysis. The corresponding element profiles of Al and O were also confirmed at the metal/n-InP contact interface using secondary ion mass spectrum (SIMS) analysis. The lowering of the Schottky barrier height due to the inhomogeneity at the metal/n-InP junction is also discussed on the basis of the TE theory. The distribution of local effective Schottky barrier heights was explained by a model incorporating the existence of double Gaussian barrier heights, which represent the high barrier and low barrier of the full distribution in the temperature ranges of 83-198 and 198-300 K. 相似文献
88.
Ting‐Ting Li Xiao Zhang Hongyang Wang Wenna Dai Shih‐Yu Huang Bing‐Chiuan Shiu Ching‐Wen Lou Jia‐Horng Lin 《先进技术聚合物》2020,31(3):451-460
The flexible polyurethane (PU) foam‐filled composite sandwiches are constructed using three types of needle‐punched fabrics (upper layer), PU foam (core layer), and nylon (bottom layer). Different contents of deionized water were used to adjust the pore size and bulk density of PU foam by free‐foaming. Effects of needle‐punched fabric components, cell structure, and fabric‐foam interface on sound absorption and compressive property of the composite sandwiches were investigated. Fabric‐foam interface contributes to improve high‐frequency sound absorption efficiency. When containing 0.5 wt% water in the core and nylon‐glass grid needle‐punched composite fabric (NPUN‐G) in the upper face, the composite sandwiches exhibited optimal sound absorption of 0.78 at low frequency of 450 Hz, and optimal compressive strength of 14.4 kPa. Combination of needle‐punched composite fabric improved the sound absorption coefficient and compressive strength, as high as 223% and 121%, respectively, compared with pure PU foam. This study provided an important basis for the preparation of high‐strength composite sandwiches with low‐frequency sound absorption. 相似文献
89.
90.