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741.
Pergolizzi G Butt JN Bowater RP Wagner GK 《Chemical communications (Cambridge, England)》2011,47(47):12655-12657
A novel, fluorescent NAD derivative is processed as substrate by three different NAD-consuming enzymes. The new probe has been used to monitor enzymatic activity in a continuous format by changes in fluorescence and, in one case, to directly visualize alternative reaction pathways. 相似文献
742.
Abdulqader Alhaider Abdel Galil Abdelgader Abdullah Arif Turjoman Keri Newell Stephen W. Hunsucker Baozhen Shan Bin Ma David S. Gibson Mark W. Duncan 《Journal of mass spectrometry : JMS》2013,48(7):779-794
The milk of the one‐humped camel (Camelus dromedarius) reportedly offers medicinal benefits, perhaps because of its unique bioactive components. Milk proteins were determined by (1) two‐dimensional gel electrophoresis and peptide mass mapping and (2) liquid chromatography–tandem mass spectrometry (LC–MS/MS) following one‐dimensional polyacrylamide gel electrophoresis. Over 200 proteins were identified: some known camel proteins including heavy‐chain immunoglobulins and others exhibiting regions of exact homology with proteins from other species. Indigenous peptides were also identified following isolation and concentration by two strategies: (1) gel‐eluted liquid fraction entrapment electrophoresis and (2) small‐scale electrophoretic separation. Extracts were analyzed by LC–MS/MS and peptides identified by matching strategies, by de novo sequencing and by applying a sequence tag tool requiring similarity to the proposed sequence, but not an exact match. A plethora of protein cleavage products including some novel peptides were characterized. These studies demonstrate that camel milk is a rich source of peptides, some of which may serve as nutraceuticals. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
743.
744.
McNamee CE Yamamoto S Butt HJ Higashitani K 《Langmuir : the ACS journal of surfaces and colloids》2011,27(3):887-894
The aim of this study was to analyze if and how monolayers of TiO(2) particles could be directly formed at the air/water interface and if these monolayers could be transferred to a solid surface. TiO(2) particles with diameters of 300 nm, 500 nm, 1 μm, 5 μm, 10 μm, and 20 μm formed stable monolayers at pH 2. At low surface pressures, the particles formed small two-dimensional aggregates. Particles up to a radius of 5 μm displayed close packing at increased surface pressures. Particles of 10 μm radius formed a loose network, which is attributed to the strong adhesion caused by the weight-induced lateral capillary attraction. Every monolayer of particles could be transformed to a solid surface by the Langmuir-Blodgett deposition. At pH 6 or 11, the particles did not form stable monolayers at the air/water interface. They were instead dispersed in the aqueous phase and eventually sank to the bottom of the trough. At pH 11 the monolayer could, however, be stabilized by the addition of salt (0.5 M NaCl). The results are interpreted based on a changed wettability of the particles depending on pH and salt concentration. 相似文献
745.
Appraisal of venomous metals in selected crops and vegetables from industrial areas of the Punjab Province 总被引:1,自引:0,他引:1
S.?N.?HusainiEmail author J.?H.?Zaidi Matiullah M.?Arif 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(3):535-541
Due to the inadequate water sources, usually sewerage water and industrial effluents are being use for irrigation of the agricultural
land around the industrial areas in Pakistan wherein crops and vegetables are cultivated. As untreated effluents contain heavy
elements, toxic metals and organic pollutants that may find its way through food chain to general public and may cause health
hazards. It is, therefore, mandatory to assess the toxic metals in such crops and vegetables. In this regard, samples of corn,
millet, cabbage, spinach and potato were collected within the vicinity of industrial areas of the Faisalabad and Gujranwala
regions. The food samples were analyzed using neutron activation analysis (NAA) technique. The highest concentration values
of Arsenic (1.9 ± 0.1 μg/g) and Cobalt (0.85 ± 0.01 μg/g) were found in cabbage whereas Manganese (91.6 ± 0.2 μg/g), Antimony
(0.15 ± 0.03 μg/g) and Selenium (1.1 ± 0.1 μg/g) were observed in spinach and Chromium (9.63 ± 1.3 μg/g) was found in millet
crop. The observed concentrations of all the toxic and heavy metals in crops and vegetables are higher than those reported
in the literature. 相似文献
746.
Magnetic properties of superconducting yttrium barium copper oxide (YBa2Cu3O7-δ) nanoparticles (31–43 nm) prepared by a chemical route have been studied. These nanoparticles have been found to clearly
exhibit ferromagnetism at room temperature while superconducting transition is observed at lower temperatures. The low temperature
hysteresis loops show evidence suggesting the presence of a large paramagnetic contribution in addition to the superconducting
contributions from the particles. Bulk YBCO obtained by pelletizing and heating the same nanoparticles at a high temperature,
displays the usual superconducting characteristics and gives no trace of ferromagnetism down to 10 K. The superconducting
transition temperature of the nanoparticles is lower than for the bulk YBCO and there is a trend of decreasing T
c with smaller size of the particles. In contrast the ferromagnetic moment increases with decreasing particle size. The development
of ferromagnetism is attributed to the presence of surface oxygen vacancies that lead to electron redistribution on the different
ions at the surface. The simultaneous decrease of superconducting T
c and the increase of ferromagnetism with decreasing size considered as being reflective of the increased role of finite size
and surface defects that weaken the superconductivity and enhance the ferromagnetism. Possible coexistence of surface ferromagnetism
and bulk superconductivity at lower temperatures is discussed. 相似文献
747.
Molecular Diversity - Machine learning (ML) methods have attracted increasing interest in chemistry as in all fields of science in recent years. This method is of great importance for the design of... 相似文献
748.
Cronin-Hennessy D Gao KY Gong DT Hietala J Kubota Y Klein T Lang BW Poling R Scott AW Smith A Zweber P Dobbs S Metreveli Z Seth KK Tomaradze A Ernst J Severini H Dytman SA Love W Savinov V Aquines O Li Z Lopez A Mehrabyan S Mendez H Ramirez J Huang GS Miller DH Pavlunin V Sanghi B Shipsey IP Xin B Adams GS Anderson M Cummings JP Danko I Napolitano J He Q Insler J Muramatsu H Park CS Thorndike EH Yang F Coan TE Gao YS Liu F Artuso M Blusk S Butt J Li J Menaa N Mountain R Nisar S 《Physical review letters》2008,100(25):251802
By using 1.8x10{6} DDpairs, we have measured B(D{0}-->pi{-}e{+}nu{e})=0.299(11)(9)%, B(D{+}-->pi{0}e{+}nu{e})=0.373(22)(13)%, B(D{0}-->K{-}e{+}nu{e})=3.56(3)(9)%, and B(D{+}-->K{0}e{+}nu{e})=8.53(13)(23)% and have studied the q;{2} dependence of the form factors. By combining our results with recent lattice calculations, we obtain |V{cd}|=0.217(9)(4)(23) and |V{cs}|=1.015(10)(11)(106). 相似文献
749.
He Q Insler J Muramatsu H Park CS Thorndike EH Yang F Coan TE Gao YS Artuso M Blusk S Butt J Li J Menaa N Mountain R Nisar S Randrianarivony K Sia R Skwarnicki T Stone S Wang JC Zhang K Bonvicini G Cinabro D Dubrovin M Lincoln A Asner DM Edwards KW Briere RA Ferguson T Tatishvili G Vogel H Watkins ME Rosner JL Adam NE Alexander JP Cassel DG Duboscq JE Ehrlich R Fields L Gibbons L Gray R Gray SW Hartill DL Heltsley BK Hertz D Jones CD Kandaswamy J Kreinick DL Kuznetsov VE Mahlke-Krüger H 《Physical review letters》2008,100(9):091801
We present measurements of D--> KS0 pi and D--> KL0 pi branching fractions using 281 pb(-1) of psi(3770) data at the CLEO-c experiment. We find that B(D0--> KS0 pi 0) is larger than B(D0--> KL0 pi 0), with an asymmetry of R(D0)=0.108+/-0.025+/-0.024. For B(D+--> KS0 pi+) and B(D+--> KL0 pi+), we observe no measurable difference; the asymmetry is R(D+)=0.022+/-0.016+/-0.018. The D0 asymmetry is consistent with the value based on the U-spin prediction A(D0--> K0 pi 0)/A(D0--> K0 pi 0)=-tan2 theta C, where theta C is the Cabibbo angle. 相似文献
750.
J. H. Zaidi M. Arif I. Fatima S. Ahmed I. H. Qureshi 《Journal of Radioanalytical and Nuclear Chemistry》1999,241(1):123-127
Rapid radiochemical neutron activation analysis (RNAA) procedures were developed and employed for the determination of 32
trace impurities in high purity aluminum thin foils. Anion exchange column chromatography was developed for the sequential
group chemical separation of various elements which helped in reducing the spectral interferences and improving the sensitivity
of the method. The procedure is simple and requires a very short time to separate the elements in three groups for radiometric
assay. To determine very low contents of uranium and thorium,239Np and233Pa as activation products were separated using anion exchange and coprecipitation methods. The impurity contents were found
to be low, therefore, their adverse effects on microelectronic devices would be negligible. Our data could partially be compared
with the data reported in literature. 相似文献