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171.
The CuOAc-catalyzed reaction of internal alkynoates with arylboronic acids proceeded under mild conditions to yield trisubstituted cinnamates stereoselectively. 相似文献
172.
Fujiwara S Okada K Shikano Y Shimizu Y Shin-Ike T Terao J Kambe N Sonoda N 《The Journal of organic chemistry》2007,72(1):273-276
N-Carbonylation of less nucleophilic nitrogen compounds was achieved by the reaction of the lithium azaenolates with carbon monoxide and selenium. This reaction proceeds in the cases of amides, formamides, ureas, and carbamates, leading to the formation of the corresponding carbamoselenoates in good to high yields after trapping with BuI. 相似文献
173.
Saito N Akagawa K Ito M Takazawa A Hayano Y Saito Y Ito M Takami H Iye M Wada S 《Optics letters》2007,32(14):1965-1967
We report on a sodium D(2) resonance coherent light source achieved in single-pass sum-frequency generation in periodically poled MgO-doped stoichiometric lithium tantalate with actively mode-locked Nd:YAG lasers. Mode-locked pulses at 1064 and 1319 nm are synchronized with a time resolution of 37 ps with the phase adjustment of the radio frequencies fed to acousto-optic mode lockers. An output power of 4.6 W at 589.1586 nm is obtained, and beam quality near the diffraction limit is also achieved in a simple design. 相似文献
174.
Niidome Y Honda K Higashimoto K Kawazumi H Yamada S Nakashima N Sasaki Y Ishida Y Kikuchi J 《Chemical communications (Cambridge, England)》2007,(36):3777-3779
Colloidal gold nanorods (GNRs), which were passivated with cationic cerasome-forming lipids having triethoxysilyl groups, were obtained in the aqueous phase by sonication of the mixture of lipids and GNRs. 相似文献
175.
A Combined Transition‐Metal‐Catalyzed and Photopromoted Process: Synthesis of 2,3‐Fused 4‐Phenylnaphthalen‐1‐yl Carboxylates from 1,7‐Diaryl‐1,6‐diynes
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Prof. Dr. Yoshihiko Yamamoto Shota Mori Dr. Masatoshi Shibuya 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(25):9093-9100
2,3‐Fused 4‐phenylnaphthalen‐1‐yl carboxylates were synthesized in a step‐ and atom‐economical manner using a ruthenium‐catalyzed hydrocarboxylative cyclization of 1,7‐diaryl‐1,6‐diynes and subsequent oxidative photocyclization. The scope of this novel two‐step process was demonstrated by the construction of diverse structures from substrates with various tethers and terminal aryl groups. Late‐stage C?H functionalizations of the arylnaphthalene product further enhance the synthetic potential of the developed process. 相似文献
176.
Inside Back Cover: A Combined Transition‐Metal‐Catalyzed and Photopromoted Process: Synthesis of 2,3‐Fused 4‐Phenylnaphthalen‐1‐yl Carboxylates from 1,7‐Diaryl‐1,6‐diynes (Chem. Eur. J. 25/2015)
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177.
Shotaro Takano Ryosuke Shiomi Yoshihiko Morimoto Dr. Takuya Kochi Prof. Dr. Fumitoshi Kakiuchi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(29):11852-11855
We report a hydroaminative cyclization of enynes using phosphine-quinolinolato rhodium catalysts. The hydroaminative cyclization of 2-vinylphenylacetylene derivatives with secondary amines gives 2-aminoindenes in good yields. The reaction is considered to proceed through carbon–carbon bond formation on a catalytically generated aminocarbene ligand. 相似文献
178.
Sayaka Suzuki Samuel L. Manzello Yoshihiko Hayashi 《Proceedings of the Combustion Institute》2013,34(2):2479-2485
Wildfires that spread into communities, commonly referred to as Wildland-Urban Interface fires (WUI), are a significant international problem. Post-fire damage studies have suggested for some time that firebrands are a significant cause of structure ignition in WUI fires, yet little research has been conducted to investigate firebrand production from burning vegetation and structures. To this end, firebrand production from real-scale building components under well-controlled laboratory conditions was investigated. Specifically, wall and re-entrant corner assemblies were ignited and during the combustion process, firebrands were collected to determine the size/mass distribution generated from such real-scale building components under varying wind speed. Finally, the size and mass distributions of firebrands collected in this study were compared with the data from an actual full-scale structure burn to determine if simple component tests such as these can provide insights into firebrand generation data from full-scale structures. The results are presented and discussed. 相似文献
179.
Kaori Kimura‐Kataoka Toshihiro Yasuda Junko Fujihara Tomoko Toga Rei‐Ichiro Ono Yosuke Otsuka Misuzu Ueki Reiko Iida Rie Sano Tamiko Nakajima Yoshihiko Kominato Hideaki Kato Haruo Takeshita 《Electrophoresis》2012,33(18):2852-2858
Five SNPs in the human DNase II gene have been reported to be associated with rheumatoid arthritis (RA). Genotype and haplotype analysis of 14 SNPs, nine SNPs of which reported in the NCBI dbSNP database in addition to these five SNPs, was performed in healthy subjects. The enzymatic activities of the amino acid substituted DNase II corresponding to each SNP and serum DNase II in healthy Japanese, and promoter activities derived from each haplotype of the RA‐related SNPs were measured. Significant correlations between genotype in each RA‐related SNP and enzymatic activity levels were found; alleles associated with RA exhibited a reduction in serum DNase II activity. Furthermore, the promoter activities of each reporter construct corresponding to predominant haplotypes in three SNPs in the promoter region of the gene exhibited significant correlation with levels of serum DNase II activity. These findings indicate these three SNPs could alter the promoter activity of DNASE2, leading to a decline in DNase II activity in the serum through gene expression. Since the three SNPs in the promoter region of the DNase II gene could affect in vivo DNase II activity through reduction of the promoter activity, it is feasible to identify these SNPs susceptible to RA. 相似文献
180.
Yoshihiko Noguchi Tomoyasu Hirose Yujiro Furuya Aki Ishiyama Kazuhiko Otoguro Satoshi Ōmura Toshiaki Sunazuka 《Tetrahedron letters》2012,53(14):1802-1807
We report the first total synthesis and reassignment of the relative stereochemistry of naturally occurring 16-hydroxy-16,22-dihydroapparicine. Our novel route proceeds by a cascade reaction to efficiently construct a 1-azabicyclo[4.2.2]decane core, along with two stereocenters (C-15 and C-16). The C-16 quaternary carbon was constructed through stereospecific 1,2-addition using an indole nucleophile to an aldehyde or a methylketone. The stereospecific synthesis of two diastereomers of the target product has revealed the true relative stereochemistry of the natural compound. 相似文献