全文获取类型
收费全文 | 91篇 |
免费 | 0篇 |
国内免费 | 2篇 |
专业分类
化学 | 45篇 |
晶体学 | 1篇 |
力学 | 3篇 |
数学 | 7篇 |
物理学 | 37篇 |
出版年
2021年 | 2篇 |
2019年 | 1篇 |
2017年 | 1篇 |
2016年 | 1篇 |
2013年 | 2篇 |
2012年 | 2篇 |
2011年 | 6篇 |
2010年 | 1篇 |
2009年 | 2篇 |
2008年 | 2篇 |
2007年 | 4篇 |
2006年 | 1篇 |
2005年 | 3篇 |
2004年 | 5篇 |
2003年 | 5篇 |
2002年 | 4篇 |
2001年 | 5篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1994年 | 7篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1981年 | 1篇 |
1980年 | 3篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1969年 | 4篇 |
1940年 | 2篇 |
1910年 | 1篇 |
排序方式: 共有93条查询结果,搜索用时 15 毫秒
1.
M. D. Zipper G. P. Simon P. Cherry A. J. Hill 《Journal of Polymer Science.Polymer Physics》1994,32(7):1237-1247
Homopolymers and blends of polycarbonate/ThermX have been investigated by differential scanning calorimetry, dynamic mechanical analysis, density measurements, and positron annihilation lifetime spectroscopy. The study focuses on the chain mobility and free volume in the amorphous miscible regions of the blends and how this mobility and free volume are affected by increasing crystallinity. It is proposed that judicious annealing, which results in increasing crystallinity (while avoiding ageing or transesterification), induces a constraint on the amorphous region leading to an increase in Tg and coalescence of free volume sites. © 1994 John Wiley & Sons, Inc. 相似文献
2.
3.
Peter C. Cherry Derek N. Evans Christopher E. Newall Nigel S. Watson Peter Murray-Rust Judith Murray-Rust 《Tetrahedron letters》1980,21(6):561-564
1,4-Addition of sulphur nucleophiles to the diene () derived the pen-2-em () from clavulanic acid provides the thiadeoxa analogues (–). X-ray analysis of the ester () shows the thermodynamically stable isomers to have the same relative stereochemistry as clavulanic acid. 相似文献
4.
Abdurashitov JN Gavrin VN Girin SV Gorbachev VV Ibragimova TV Kalikhov AV Khairnasov NG Knodel TV Kornoukhov VN Mirmov IN Shikhin AA Veretenkin EP Vermul VM Yants VE Zatsepin GT Bowles TJ Nico JS Teasdale WA Wark DL Cherry ML Karaulov VN Levitin VL Maev VI Nazarenko PI Shkol'nik VS Skorikov NV Cleveland BT Daily T Davis R Lande K Lee CK Wildenhain PW Khomyakov YS Zvonarev AV Elliott SR Wilkerson JF 《Physical review letters》1996,77(23):4708-4711
5.
The complexing ability of a range of 19 symmetrical, unsymmetrical and bridged calix[4]arene derivatives having ester, ketone, amide, amine and thioether functionalities were determined by the picrate extraction method. On incorporating these calix[4]arene derivatives as neutral carrier ionophores in sodium-selective poly (vinyl chloride) membrane electrodes the performance was assessed on the basis of the sensitivity and selectivity over the alkali, alkaline earth metals and hydrogen and ammonium ions. The temperature dependence, response times and lifetimes were also determined. Four ionophores in particular gave excellent sensitivity and selectivity and lifetimes of > 200 days. These electrodes were then tested without additional lipophilic additives and one ionophore was incorporated into poly (vinyl chloride) membrane electrodes with plasticizing solvents of varying polarity. 相似文献
6.
Abazov AI Anosov OL Faizov EL Gavrin VN Kalikhov AV Knodel TV Knyshenko II Kornoukhov VN Mezentseva SA Mirmov IN Ostrinsky AV Pshukov AM Revzin NE Shikhin AA Timofeyev PV Veretenkin EP Vermul VM Zatsepin GT Bowles TJ Cleveland BT Elliott SR O'Brien HA Wark DL Wilkerson JF Davis R Lande K Cherry ML Kouzes RT 《Physical review letters》1991,67(24):3332-3335
7.
8.
Gabriela Ionita Petre Ionita Victor EM. Sahini Constantin Luca 《Journal of inclusion phenomena and macrocyclic chemistry》2001,39(3-4):269-271
The kinetics of oxidation of amino acids (Arg, His, Lys, Phe, Thr and Tyr), a dipeptide (Gly-His), and BSA (bovine serum albumin) by two persistent water soluble free radicals of the hydrazyl type has been studied.The rate decreases in the order Arg>Lys>Tyr>Thr>HisBSAPheGly-His with bothfree radicals. Addition to the reaction mixture of - and -cyclodextrin decreases the oxidation rate, probably due to amino acidencapsulation in the cyclodextrin cavity. -Cyclodextrin protects more efficiently against oxidation than -cyclodextrin. 相似文献
9.
For plane-wave and many-spiral states of the experimentally based Luo-Rudy 1 model of heart tissue in large (8 cm square) domains, we show that a space-time-adaptive time-integration algorithm can achieve a factor of 5 reduction in computational effort and memory-but without a reduction in accuracy-when compared to an algorithm using a uniform space-time mesh at the finest resolution. Our results indicate that such an algorithm can be extended straightforwardly to simulate quantitatively three-dimensional electrical dynamics over the whole human heart. 相似文献
10.