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排序方式: 共有1202条查询结果,搜索用时 15 毫秒
941.
942.
943.
944.
Yugo Kuriki Takafusa Yoshioka Mako Kamiya Toru Komatsu Hiroyuki Takamaru Kyohhei Fujita Hirohisa Iwaki Aika Nanjo Yuki Akagi Kohei Takeshita Haruaki Hino Rumi Hino Ryosuke Kojima Tasuku Ueno Kenjiro Hanaoka Seiichiro Abe Yutaka Saito Jun Nakajima Yasuteru Urano 《Chemical science》2022,13(16):4474
Fluorescent probes that can selectively detect tumour lesions have great potential for fluorescence imaging-guided surgery. Here, we established a library-based approach for efficient screening of probes for tumour-selective imaging based on discovery of biomarker enzymes. We constructed a combinatorial fluorescent probe library for aminopeptidases and proteases, which is composed of 380 probes with various substrate moieties. Using this probe library, we performed lysate-based in vitro screening and/or direct imaging-based ex vivo screening of freshly resected clinical specimens from lung or gastric cancer patients, and found promising probes for tumour-selective visualization. Further, we identified two target enzymes as novel biomarker enzymes for discriminating between tumour and non-tumour tissues. This library-based approach is expected to be an efficient tool to develop tumour-imaging probes and to discover new biomarker enzyme activities for various tumours and other diseases.Efficient methodology to develop tumor-imaging fluorescent probes based on screening with our newly constructed probe library for aminopeptidase/protease (380 probes) and clinical samples has been established. 相似文献
945.
Seiya Fukagawa Masahiro Kojima Tatsuhiko Yoshino Shigeki Matsunaga 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(50):18322-18326
Catalytic enantioselective directed methylene C(sp3)?H amidation reactions of 8‐alkylquinolines using a Cp*RhIII/chiral carboxylic acid (CCA) hybrid catalytic system are described. A binaphthyl‐based chiral carboxylic acid efficiently differentiates between the enantiotopic methylene C?H bonds, which leads to the formation of C?N bonds with good enantioselectivity. 相似文献
946.
We investigated the enhancing effect of three alkyl-2-pyrrolidones on transdermal penetration of phenolsulfonphthalein (phenol red) and indomethacin from an aqueous vehicle by using an in vitro technique with excised rat skin. The enhancers included 1-methyl- (I), 1-hexyl- (II) and 1-lauryl-2-pyrrolidone (III). These derivatives effectively enhanced the penetration and skin accumulation of phenol red and indomethacin. Lipophilic enhancers such as II and III showed particularly high enhancing effects. The penetration profiles of phenol red and indomethacin showed a lag phase followed by a linear increase. Compounds II and III showed long lag times. The enhancer penetration was also determined. Compounds I and II showed a slight penetration. Compound III showed little penetration but high skin accumulation. 相似文献
947.
Eiki Tomita Kodai Yamada Dr. Yu Shibata Prof. Dr. Ken Tanaka Dr. Masahiro Kojima Dr. Tatsuhiko Yoshino Prof. Dr. Shigeki Matsunaga 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(26):10560-10564
The synthesis, characterization, and catalytic performance of iridium(III) catalysts that bear an amide-pendant cyclopentadienyl ligand ([CpAIrI2]2) is reported. These [CpAIrI2]2 catalysts were obtained from the complexation of a CpA ligand precursor with [Ir(cod)OAc]2 followed by oxidation. Double aromatic homologation reactions of benzamides with alkynes by fourfold C−H activation proceeded in good to high yield with these [CpAIrI2]2 catalysts, demonstrating their superior catalytic performance in this challenging transformation. 相似文献
948.
Dr. Tatsuhiro Kojima Hiroto Takeda Dr. Naoto Kuwamura Prof. Takumi Konno 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(64):15981-15985
Solvent-mediated crystal-to-crystal transformations of [Au6Ag3Cu3(H2O)3(d -pen)6(tdme)2]3+ (d -[ 1 (H2O)3]3+; pen2−= penicillaminate, tdme=1,1,1-tris(diphenylphosphinomethyl)ethane) to form unique supramolecular species are reported. Soaking crystals of d -[ 1 (H2O)3]3+ in aqueous Na2bdc (bdc2−=1,4-benzenedicarboxylate) yielded crystals containing d -[ 1 (bdc)(H2O)2]+ due to the replacement of a terminal aqua ligand in d -[ 1 (H2O)3]3+ by a monodentate bdc2− ligand. When γ-cyclodextrin (γ-CD) was added to aqueous Na2bdc, d -[ 1 (H2O)3]3+ was transformed to d -[ 1 (bdc@γ-CD)(H2O)2]+, where a γ-CD ring was threaded by a bdc2− molecule to construct a pseudorotaxane structure. While the use of dicarboxylates with an aliphatic carbon chain instead of bdc2− afforded analogous pseudorotaxanes, such pseudorotaxane species were not formed when crystals of [Au6Ag3Cu3(H2O)3(l -pen)6(tdme)2]3+ (l -[ 1 (H2O)3]3+) enantiomeric to d -[ 1 (H2O)3]3+ were soaked in aqueous Na2bdc and γ-CD, affording only crystals containing l -[ 1 (bdc)(H2O)2]+. 相似文献
949.
Radial rutile TiO2 nanorod homomesocrystals (TiO2-NR HOMCs) or the so-called “sea urchin-like TiO2 microspheres” were synthesized by using a hydrothermal method. TiO2-NR HOMCs show photocatalytic activity for aerobic oxidative degradation of 2-naphthol under irradiation of UV- and visible light. Furthermore, extremely small iron oxide clusters were formed on the surface of TiO2-NR HOMCs (FeOx/TiO2-NR HOMCs) by the chemisorption-calcination technique to reduce the band gap. The FeOx-surface modification gives rise to drastic enhancement of the UV- and visible-light activity. Reversed double-beam photoacoustic spectroscopy measurements were performed for TiO2-NR HOMCs and FeOx/TiO2-NR HOMCs to obtain the ERDT (energy-resolved distribution of electron traps)/CBB (conduction-band bottom) patterns. The ERDT/CBB pattern of TiO2-NR HOMCs consists of two components derived from rutile (C1) and amorphous TiO2 (C2). In the pattern, the surface electron traps in C2 exist near the CBB to be removed by the FeOx-surface modification. By taking this finding into consideration, the striking surface modification effect is ascribable to the electrocatalytic activity (or the action as an electron reservoir) of the FeOx clusters for multiple ORR, the suppression of recombination, and the increase in the visible-light harvesting efficiency. 相似文献
950.
Narumi Komami Keitaro Matsuoka Ayako Nakano Dr. Masahiro Kojima Dr. Tatsuhiko Yoshino Prof. Dr. Shigeki Matsunaga 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(5):1217-1220
Monoaryl-λ3-iodanes are potentially attractive arylating agents. They are generally synthesized from aryl iodides via oxidation, which can cause functional group incompatibility, especially when polyfunctionalized derivatives are desired. This work describes the direct synthesis of monoaryl-λ3-iodanes through a chemoselective ipso-substitution reaction of arylgermanes and arylstannanes with iodine tris(trifluoroacetate). The generated iodanes were converted to iodonium ylides or used for further transformations in one pot. The presented method enables the preparation of polyfunctionalized monoaryl-λ3-iodanes. 相似文献