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81.
Ammar R Baringer P Coppage D Davis R Kelly M Kwak N Lam H Ro S Kubota Y Lattery M Nelson JK Perticone D Poling R Schrenk S Wang R Alam MS Kim IJ Nemati B Romero V Sun CR Wang P Zoeller MM Crawford G Fulton R Gan KK Kagan H Kass R Lee J Malchow R Morrow F Sung MK Whitmore J Wilson P Butler F Fu X Kalbfleisch G Lambrecht M Skubic P Snow J Bortoletto D Brown DN Dominick J McIlwain RL Miller DH Modesitt M Shibata EI Schaffner SF Shipsey IP Battle M Ernst J Kroha H Roberts S Sparks K Thorndike EH 《Physical review D: Particles and fields》1992,45(11):3976-3985
82.
Alexander J Artuso M Bebek C Berkelman K Browder T Cassel DG Cheu E Coffman DM Crawford G DeWire JW Drell PS Ehrlich R Galik RS Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Kandaswamy J Katayama N Kreinick DL Lewis JD Ludwig GS Mistry NB Mueller J Nandi S Nordberg E O'Grady C Peterson D Pisharody M Riley D Sapper M Selen M Silverman A Stone S Worden H Worris M Sadoff AJ Avery P Besson D Garren L Yelton J Bowcock T Kinoshita K Pipkin FM Procario M Wilson R Wolinski J Xiao D Zhu Y 《Physical review letters》1990,65(13):1531-1534
83.
Jin-Seong ParkChang-Eun Yeom Soo Hyuk ChoiYong Shik Ahn Sunggu Ro Young Ho Jeon Dong-Kyu Shin B.Moon Kim 《Tetrahedron letters》2003,44(8):1611-1614
An orthogonally protected β,γ′-diamino acid 6 possessing conformationally-constrained ring system was synthesized as a novel cyclic amino acid analogue. This synthesis involves as key steps chemoselective enzymatic hydrolysis of cis-piperidine-3,5-dicarboxylic ester derivative followed by efficient kinetic resolution of the partially resolved half-acid to afford the C1-symmetric piperidine-3,5-dicarboxylic acid monoester in high enantiomeric excess (>98% ee). The optically active half-acid was transformed to the cyclic amino acid via Curtius-type rearrangement. 相似文献
84.
This paper describes the procedures of isolating strontium and yttrium from seawater that enable the determination of 89,90Sr. In one procedure, strontium is directly isolated from seawater on the column filled with Sr resin by binding of strontium to the resin from 3 M HNO3 in a seawater, and successive elution with HNO3. In others, strontium is precipitated from seawater with (NH4)2CO3, followed by isolation on a Sr column or an anion exchange column. It is shown that strontium precipitation is optimal with concentration of 0.3 M (NH4)2CO3 at pH = 11. In these conditions, 100% Y, 78% Sr, 80% Ca and 50% Mg are precipitated. Strontium is bound on to Sr column from 5 to 8 M HNO3, separated from other elements by elution with 3 M HNO3 and 0.05 M HNO3. Strontium and yttrium are bound on to anion exchange column from alcoholic solutions of nitric acid. The optimum mixture of alcohols for sample binding is a mixture of ethanol and methanol with the volume ratio 1:3. Strontium and yttrium are separated from Mg, Ca, K, and other elements by elution with 0.25 M HNO3 in the mixture of ethanol and methanol. After the separation, yttrium and strontium are eluted from the column with water or methanol.In the procedure of direct isolation from 1 l of the sample, the average recovery of 50% was obtained. In the remaining two procedures, the strontium recovery was about 60% for the Sr column and 65% for anion exchange column. Recovery of yttrium is about 70% for the anion exchange column. It turned out that the procedure with the Sr resin (direct isolation and isolation after precipitation) is simpler and faster in the phase of the isolation on the column in comparison with the procedure with the anion exchanger. The procedure with the anion exchanger, however, enables the simultaneous isolation of yttrium and strontium and rapid determination of 89,90Sr. These procedures were tested by determination of 89,90Sr on liquid scintillation counter and Cherenkov counting in 5 M HNO3. Obtained results showed that activity of 50 mBq l−1 of 89,90Sr and higher can be simultaneously determined. 相似文献
85.
The ligand of Numb protein-X (LNX) family, also known as the PDZRN family, is composed of four discrete RING-type E3 ubiquitin ligases (LNX1, LNX2, LNX3, and LNX4), and LNX5 which may not act as an E3 ubiquitin ligase owing to the lack of the RING domain. As the name implies, LNX1 and LNX2 were initially studied for exerting E3 ubiquitin ligase activity on their substrate Numb protein, whose stability was negatively regulated by LNX1 and LNX2 via the ubiquitin-proteasome pathway. LNX proteins may have versatile molecular, cellular, and developmental functions, considering the fact that besides these proteins, none of the E3 ubiquitin ligases have multiple PDZ (PSD95, DLGA, ZO-1) domains, which are regarded as important protein-interacting modules. Thus far, various proteins have been isolated as LNX-interacting proteins. Evidence from studies performed over the last two decades have suggested that members of the LNX family play various pathophysiological roles primarily by modulating the function of substrate proteins involved in several different intracellular or intercellular signaling cascades. As the binding partners of RING-type E3s, a large number of substrates of LNX proteins undergo degradation through ubiquitin-proteasome system (UPS) dependent or lysosomal pathways, potentially altering key signaling pathways. In this review, we highlight recent and relevant findings on the molecular and cellular functions of the members of the LNX family and discuss the role of the erroneous regulation of these proteins in disease progression. 相似文献
86.
L. Hock B. Helferich K. Neumann F. Peters H. Schmidt W. Lauppe B. Roßmann 《Colloid and polymer science》1951,123(1):54-56
Ohne Zusammenfassung 相似文献
87.
E. Mergel G. Schönwaβer H. Hübel D. Roβbach P. G. Thirolf M. Chromik D. Gassmann D. Habs P. Reiter 《Acta Physica Hungarica A》2001,13(1-3):199-202
Transitions between nuclear states with a large deformation difference may have large transition probabilities for E0 decay. Such an E0 decay has been found in the decay of the superdeformed 238U fission isomer back into the normal-deformed states [1]. However, a search for the E0 back-decay in 236U showed no result [2]. A setup has been developed to search for conversion electrons in this decay. 相似文献
88.
We present a method to deposit a wide range of radioactive probe atoms on surfaces, without introducing lattice damage or
contaminating the surface with other elements or isotopes. In this method, the probe atoms are mass-separated using an isotope
separator, decelerated to 5 eV, and directly deposited on the surface. The method allows for performing hyperfine interactions
experiments using trace amounts of radioactive probes located at surfaces and interfaces. The characteristics of the deposition
method will be described, with particular attention to the deceleration stage of the isotope separator. The method was tested
with perturbed angular correlation (PAC) experiments on the system In on Cu(17,1,1). The results are in agreement with molecular
dynamics simulations of the deposition process. New developments, in particular the study of the self-diffusion of Ag atoms
on Ag(100) by means of PAC with the 111Ag probe, are briefly discussed.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
89.
A polymeric film of a biodegradable poly(p‐dioxanone) was grown from 490 nm silica particles by monolayer formation via self‐assembly of hydroxy‐terminated triethoxysilane and subsequent surface‐initiated ring‐opening polymerization of p‐dioxanone. The resulting silica/poly(p‐dioxanone) hybrid particles were characterized by means of 1H NMR spectroscopy, IR spectroscopy, thermogravimetric analysis, field‐emission scanning electron microscopy, and energy‐dispersive X‐ray spectroscopy.
90.
Hyun Jung Hong Kyong Hye Joung Yong Kyung Kim Min Jeong Choi Seul Gi Kang Jung Tae Kim Yea Eun Kang Joon Young Chang Joon Ho Moon Sangmi Jun Hyun-Joo Ro Yujeong Lee Hyeongseok Kim Jae-Hyung Park Baeki E. Kang Yunju Jo Heejung Choi Dongryeol Ryu Chul-Ho Lee Hail Kim Kyu-Sang Park Hyun Jin Kim Minho Shong 《Experimental & molecular medicine》2022,54(7):932