全文获取类型
收费全文 | 492篇 |
免费 | 29篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 21篇 |
化学工业 | 197篇 |
金属工艺 | 17篇 |
机械仪表 | 11篇 |
建筑科学 | 12篇 |
能源动力 | 22篇 |
轻工业 | 44篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
无线电 | 34篇 |
一般工业技术 | 92篇 |
冶金工业 | 8篇 |
原子能技术 | 27篇 |
自动化技术 | 37篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 7篇 |
2021年 | 11篇 |
2020年 | 14篇 |
2019年 | 15篇 |
2018年 | 21篇 |
2017年 | 14篇 |
2016年 | 21篇 |
2015年 | 14篇 |
2014年 | 10篇 |
2013年 | 48篇 |
2012年 | 17篇 |
2011年 | 29篇 |
2010年 | 27篇 |
2009年 | 29篇 |
2008年 | 28篇 |
2007年 | 17篇 |
2006年 | 23篇 |
2005年 | 24篇 |
2004年 | 12篇 |
2003年 | 15篇 |
2002年 | 13篇 |
2001年 | 11篇 |
2000年 | 7篇 |
1999年 | 9篇 |
1998年 | 7篇 |
1997年 | 11篇 |
1996年 | 11篇 |
1995年 | 4篇 |
1994年 | 1篇 |
1993年 | 5篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 6篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 5篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1977年 | 1篇 |
1974年 | 2篇 |
1972年 | 2篇 |
1971年 | 1篇 |
排序方式: 共有524条查询结果,搜索用时 15 毫秒
521.
Dr. Chie Hashimoto Dr. Wataru Nomura Dr. Tetsuo Narumi Dr. Masayuki Fujino Dr. Hiroshi Tsutsumi Masaki Haseyama Prof. Naoki Yamamoto Dr. Tsutomu Murakami Prof. Hirokazu Tamamura 《ChemMedChem》2013,8(10):1668-1672
The human immunodeficiency virus type 1 (HIV‐1) uses CD4 and the co‐receptor CCR5 or CXCR4 in the process of cell entry. The negatively charged extracellular domains of CXCR4 (CXCR4‐ED) interact with positive charges on the V3 loop of gp120, facilitating binding via electrostatic interactions. The presence of highly conserved positively charged residues in the V3 loop suggests that CXCR4‐ED‐derived inhibitors might be broadly effective inhibitors. Synthetic peptide derivatives were evaluated for anti‐HIV‐1 activity. The 39‐mer extracellular N‐terminal region (NT) was divided into three fragments with 10‐mer overlapping sites ( N1 – N3 ), and these linear peptides were synthesized. Peptide N1 contains Met 1–Asp 20 and shows significant anti‐HIV‐1 activity. Extracellular loops 1 and 2 (ECL1 and 2) were mimicked by cyclic peptides C1 and C2 , which were synthesized by chemoselective cyclization. Cyclic peptides C1 and C2 show higher anti‐HIV‐1 activity than their linear peptide counterparts, L1 and L2 . The cytotoxicities of C1 and C2 are lower than those of L1 and L2 . These results indicate that Met 1–Asp 20 segments of the NT and cyclic peptides of ECL1 and ECL2 are potent anti‐HIV‐1 drug candidates. 相似文献
522.
Catalytic behavior of Bi2Mo3O12 supported on CoMoO4 or CO11/12Fe1/12MoO
x
was investigated in the oxidation of propylene to acrolein. A drastic promotion effect was observed only in the catalyst supported on Co11/12Fe1/12MoO
x
. but not on CoMoO4. Promotion effect of cobalt and iron in the multicomponent bismuth molybdate catalyst, Mo-Bi-MII-MIII-O was discussed. 相似文献
523.
Takashi Kojima Wataru Sakamoto Toshinobu Yogo Takashi Fujii Shin-ichi Hirano 《Journal of the American Ceramic Society》2000,83(2):281-286
A Ce-TZP/platelike La(Co(Fe0.9 Al0.1 )11 )O19 composite was synthesized in situ while sintering from a mixture of Ce-TZP, La(Fe0.9 Al0.1 )O3 , Fe2 O3 , Al2 O3 , and CoO powders. Platelike La(Co(Fe0.9 Al0.1 )11 )O19 crystals were grown in a dense Ce-TZP matrix after sintering at temperatures of 1200°–1350°C. The temperature range for sintering Ce-TZP/La(Fe,Al)12 O19 composites was expanded widely by substituting Co2+ ions for Fe2+ ions in its structure. The highest value of the bending strength of the Ce-TZP/La(Co(Fe0.9 Al0.1 )11 )O19 composites was 880 MPa, which was higher than that of the Ce-TZP/La(Fe,Al)12 O19 composite (780 MPa) and Ce-TZP (513 MPa). The saturation magnetization of the Ce-TZP/La(Co(Fe0.9 Al0.1 )11 )O19 composite was a constant value of 7.7 emu/g after the composite was sintered at 1200°–1350°C. 相似文献
524.
Wataru Kuriyama Yasunori Ino Osamu Ogata Noboru Sayo Takao Saito 《Advanced Synthesis \u0026amp; Catalysis》2010,352(1):92-96
A ruthenium complex was found to catalyze the hydrogen reduction of esters under mild and neutral conditions. A variety of optically active esters can be reduced to the corresponding alcohols in excellent yield without loss of their optical purity or causing undesirable side reactions. Hydrogen reduction needs such simple operations – reaction, concentration, and purification – that the violent quench step and extraction step, which accompany conventional sodium borohydride or lithium aluminum hydride reduction, can be omitted. 相似文献