全文获取类型
收费全文 | 325篇 |
免费 | 8篇 |
国内免费 | 1篇 |
专业分类
化学 | 268篇 |
晶体学 | 6篇 |
力学 | 2篇 |
数学 | 19篇 |
物理学 | 39篇 |
出版年
2022年 | 2篇 |
2021年 | 3篇 |
2020年 | 5篇 |
2019年 | 12篇 |
2018年 | 10篇 |
2017年 | 8篇 |
2016年 | 3篇 |
2015年 | 4篇 |
2014年 | 7篇 |
2013年 | 7篇 |
2012年 | 23篇 |
2011年 | 21篇 |
2010年 | 20篇 |
2009年 | 17篇 |
2008年 | 24篇 |
2007年 | 29篇 |
2006年 | 15篇 |
2005年 | 17篇 |
2004年 | 25篇 |
2003年 | 18篇 |
2002年 | 13篇 |
2001年 | 9篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 9篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 1篇 |
1985年 | 6篇 |
1984年 | 4篇 |
1982年 | 2篇 |
1975年 | 4篇 |
1971年 | 1篇 |
排序方式: 共有334条查询结果,搜索用时 78 毫秒
101.
102.
Tatsuro Ouchi Satoshi Jokei Hidenori Chikashita 《Journal of heterocyclic chemistry》1982,19(4):935-936
1,2:5,6-Di-O-isopropylidene-3-O-[3-(uracil-1-yl)propionoyl]-α-D-glucofuranose and 1,2-mono-O-isopropylidene-6-O-[3-(uracil-1-yl)propionoyl]-α-D-glucofuranose were synthesized. 相似文献
103.
Hidenori Kimura 《Journal of Optimization Theory and Applications》1971,8(6):431-440
A simple condition which assures the existence of the saddle point is derived for nonlinear differential games of prescribed duration. It is shown that this condition removes the possibility of a kind of singularity which is a source of many troublesome phenomena in differential games. 相似文献
104.
Nishida H Miyazaki Y Mukaihira T Saitoh F Fukui M Harada K Itoh M Muraoka A Matsusue T Okamoto A Hosaka Y Matsumoto M Ohnishi S Mochizuki H 《Chemical & pharmaceutical bulletin》2002,50(9):1187-1194
Intravascular clot formation is an important event in a number of cardiovascular diseases. The prevention of blood coagulation has become a major target for new therapeutic agents. Factor Xa (FXa) is a trypsin-like serine protease that plays a key role in the blood coagulation cascade and represents an attractive target for anticoagulant drug development. We have investigated substituents in the central part of a lead compound (3: M55113), and discovered that compound M55551 (34: (R)-4-[(6-Chloro-2-naphthalenyl)sulfonyl]-6-oxo-1-[[1-(4-pyridinyl)-4-piperidinyl]methyl]-2-piperazinecarboxylic acid) is a potent inhibitor of FXa (IC(50)=0.006 microM), with high selectivity for FXa over trypsin and thrombin. The activity of this compound is ten times more powerful than the lead compound. 相似文献
105.
Catalytic asymmetric Diels–Alder reaction of α-amino-o-quinodimethane with α,β-unsaturated aldehydes was achieved with high diastereo- and enantioselectivities in the presence of l-proline, which acts as a promoter to generate the quinodimethane from the corresponding precursor as well as a chiral catalyst for the enantioselective Diels–Alder reaction. 相似文献
106.
Ryoichi Kishi Kazuaki Hiroki Taiki Tominaga Ken‐Ichi Sano Hidenori Okuzaki Jose G. Martinez Toribio F. Otero Yoshihito Osada 《Journal of Polymer Science.Polymer Physics》2012,50(11):790-796
Novel electro‐conductive and mechanically‐tough double network polymer hydrogels (E‐DN gels) were synthesized by polymerization of 3, 4‐ethylenedioxythiophene in the presence of a double network hydrogel (DN gel) matrix. The E‐DN gels showed not only excellent mechanical performance, having a fracture stress of 1.4–2.1 MPa, but also electrical conductivity as high as 10?3 S cm?1, both under dry and water‐swollen states. The fracture stress and fracture energy of the E‐DN gel was increased by 1.7 and 3.4 times, respectively, as compared with the DN gel. From scanning electron microscope and AFM observations, it was found that electro‐conductive poly(3,4‐ethylenedioxythiophene) (PEDOT) was incorporated into DN gel matrix, apparently due to the formation of a poly‐ion complex with sulfonic acid group of the DN gel network. Thus, PEDOT incorporated into the DN gel matrix greatly improves not only electronic conductivity, but also mechanical properties, reinforcing the double network gel matrix. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
107.
Dr. Masahiro Yamamoto Dr. Ryuhei Nakamura Dr. Takafumi Kasaya Dr. Hidenori Kumagai Dr. Katsuhiko Suzuki Dr. Ken Takai 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(21):5819-5822
Deep-sea hydrothermal vents discharge abundant reductive energy into oxidative seawater. Herein, we demonstrated that in situ measurements of redox potentials on the surfaces of active hydrothermal mineral deposits were more negative than the surrounding seawater potential, driving electrical current generation. We also demonstrated that negative potentials in the surface of minerals were widespread in the hydrothermal fields, regardless of the proximity to hydrothermal fluid discharges. Lab experiments verified that the negative potential of the mineral surface was induced by a distant electron transfer from the hydrothermal fluid through the metallic and catalytic properties of minerals. These results indicate that electric current is spontaneously and widely generated in natural mineral deposits in deep-sea hydrothermal fields. Our discovery provides important insights into the microbial communities that are supported by extracellular electron transfer and the prebiotic chemical and metabolic evolution of the ocean hydrothermal systems. 相似文献
108.
109.
Brenden McDearmon Eunhee Lim Kathryn O'Hara Hidenori Nakayama Yingdong Luo Michael L. Chabinyc Craig J. Hawker 《Journal of polymer science. Part A, Polymer chemistry》2017,55(16):2618-2628
A new pentacyclic building block, benzodibenzofuranquinone (BDBFQ), is synthesized in a single step from the inexpensive and readily available feedstocks chloranil and 3‐bromophenol. This versatile repeat unit is incorporated into a series of conjugated materials as either the redox active quinone form or as an electron‐rich dialkylated benzodibenzofuran (BDBF) unit. To illustrate the performance that can be obtained from these systems, optical and electrochemical properties were studied via UV–vis–NIR spectroscopy and cyclic voltammetry. Thin‐film morphology was characterized via grazing incidence wide‐angle X‐ray scattering with thin‐film field‐effect transistor measurements further demonstrating the utility of this system. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2618–2628 相似文献
110.