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121.
Antonilêni F. D. Medeiros Ana Flávia O. Santos F. S. de Souza J. V. V. Procópio Márcia Ferraz Pinto R. O. Macêdo 《Journal of Thermal Analysis and Calorimetry》2007,87(2):377-382
Organobentonites were synthesized by treating Na-bentonites (Wyomingand Re?adiye) with cetylpyridinium chloride (CPC) using ion exchangemethod. The difference in the basal spacing by 0.65 Å and a higher massloss by 13.32% of organobentonite (Wyoming) in the temperature range 200–550°Ccomparing with that of organobentonite (Re?adiye) were in conformitywith the CEC values of organobentonites. The HOH stretching and bending peaksof bentonites became sharper following the treatment with the organo-cation.The intensity decrease of the Al–OH band for organobentonite (Re?adiye)and in particular, the significantly higher amount of m-cresolretained by the organobentonite of lower CEC than that by the organobentonite(Wyoming) indicate the influence of the CP cation on the adsorption process. 相似文献
122.
123.
A simple and sensitive method for the determination of baclofen in plasma is described. Baclofen and the internal standard, KM 08205, were isolated from plasma by solid-phase extraction using C18 material. After separation by reversed-phase liquid chromatography, the analytes were detected with tandem mass spectrometry. The extraction procedure was optimised regarding the solid-phase extraction material, the pH in the conditioning solution and the washing volume. The method was proven to be selective and sensitive with an absolute recovery of about 95%, a relative standard deviation below 5% and a limit of quantification of 10 nmol/1. 相似文献
124.
Human blood group A and B glycosyltransferases (GTA, GTB) are retaining glycosyltransferases, requiring a catalytic mechanism that conserves the anomeric configuration of the hexopyranose moiety of the donor substrate (UDP-GalNAc, UDP-Gal). Previous studies have shown that GTA and GTB cycle through structurally distinct states during catalysis. Here, we link binding and release of substrates, substrate-analogs, and products to transitions between open, semi-closed, and closed states of the enzymes. Methyl TROSY based titration experiments in combination with zz-exchange experiments uncover dramatic changes of binding kinetics associated with allosteric interactions between donor-type and acceptor-type ligands. Taken together, this highlights how allosteric control of on- and off-rates correlates with conformational changes, driving catalysis to completion. 相似文献
125.
D. Rodríguez G. Ban D. Durand F. Duval X. Fléchard E. Liénard F. Mauger A. Méry O. Naviliat-Cuncic J. -C. Thomas Ph. Velten 《The European Physical Journal A - Hadrons and Nuclei》2009,42(3):397-400
The LPCTrap setup at GANIL is fully operational since 2006. The first breakthrough was the detection of 100000 coincidences between the $ \beta$ particles and the recoil ions from the decay of 6He+ produced by the SPIRAL source. After preparation, the decaying nuclei are confined in a transparent Paul trap which is surrounded by a $ \beta$ -telescope made of a double-sided silicon strip detector followed by a scintillator, and by a micro-channel plate position-sensitive detector to record in coincidence the $ \beta$ particles and the recoil ions. Simulations of this system are needed in order to study possible systematic effects and extract with high accuracy the $ \beta$ - $ \nu$ angular-correlation coefficient. A code based on Geant4 is well suited for this purpose. In this contribution the results from the simulations compared with those from the experiment will be presented and discussed. 相似文献
126.
Sonja Herres‐Pawlis Dr. Tarimala Seshadri Ulrich Flörke Gerald Henkel Prof. Dr. 《无机化学与普通化学杂志》2009,635(8):1209-1214
The reaction of 2,2′‐Bis(2N‐(1,1′,3,3′‐tetramethyl‐guanidino))diphenylene‐amine (TMG2PA) ( 1 ) with CuI in MeCN results in the formation of [CuII(TMG2PAamid)I] ( 2 ) indicatingthat CuI is the target of an oxidative attack of the N‐H proton of the ligand which itself is converted to molecular hydrogen. In contrast, if [Cu(MeCN)4][PF6] is used as the CuI source, [CuI2(TMGbenz)2][PF6]2 ( 3 ) is obtained instead. The use of the non‐coordinating counterion [PF6]– apparently prevents CuI from oxidation but induces itself a cyclisation reaction within the ligand which results in the formation of a benzimidazole‐guanidine ligand. 相似文献
127.
Janna Börner M. Sc. Ulrich Flörke Dr. Klaus Huber Prof. Dr. Artjom Döring Dipl.‐Chem. Dirk Kuckling Prof. Dr. Sonja Herres‐Pawlis Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(10):2362-2376
New class of air‐stable catalysts for lactide polymerisation: Guanidine–pyridine hybrid ligands (picture, left) were used to prepare a series of zinc complexes (e.g., depicted cation [ZnL2(CF3SO3)]+, where L is the quinoline‐containing ligand with R1=R2=R3=R4=Me), in which the ligand binds through two different N‐donor atoms. The zinc complexes show high activity in ring‐opening polymerisation of d,l ‐lactide (right), giving polylactide with molecular masses up to 176 000 g mol?1 and in high yield.
128.
Fátima Duarte Freire C. Flávio Soares Aragão T. Flávio Accioly de Lima e Moura Fernanda Nervo Raffin 《Journal of Thermal Analysis and Calorimetry》2009,97(1):355-357
Chlorpropamide ((4-chloro-N-(propylamino)-carbonyl)-benzenesulfonamide) belongs to compounds having sulfonylurea group and is widely used as an oral
antidiabetic agent. In this work differential scanning calorimetry (DSC) was used during pre-formulation of chlorpropamide
tablets to determine the drug-excipients compatibility. The DSC curves of chlorpropamide and binary mixtures with excipients
(sodium croscarmellose, sodium lauryl sulfate, microcrystalline cellulose, magnesium stearate and calcium carbonate) showed
that chlorpropamide exhibited interaction with magnesium stearate and sodium lauryl sulfate. The binary mixtures of chlorpropamide–magnesium
stearate presented a single endothermic process at 96–108 °C and chlorpropamide–sodium lauryl sulfate showed a wide endotherm
at 99–120 °C. 相似文献
129.
E. Bagnaschi M. Borsato K. Sakurai O. Buchmueller R. Cavanaugh V. Chobanova M. Citron J. C. Costa A. De Roeck M. J. Dolan J. R. Ellis H. Flächer S. Heinemeyer G. Isidori M. Lucio F. Luo D. Martínez Santos K. A. Olive A. Richards G. Weiglein 《The European Physical Journal C - Particles and Fields》2017,77(4):268
We perform a likelihood analysis of the minimal anomaly-mediated supersymmetry-breaking (mAMSB) model using constraints from cosmology and accelerator experiments. We find that either a wino-like or a Higgsino-like neutralino LSP, \(\tilde{\chi }^0_{1}\), may provide the cold dark matter (DM), both with similar likelihoods. The upper limit on the DM density from Planck and other experiments enforces \(m_{\tilde{\chi }^0_{1}} \lesssim 3 \,\, \mathrm {TeV}\) after the inclusion of Sommerfeld enhancement in its annihilations. If most of the cold DM density is provided by the \(\tilde{\chi }^0_{1}\), the measured value of the Higgs mass favours a limited range of \(\tan \beta \sim 5\) (and also for \(\tan \beta \sim 45\) if \(\mu > 0\)) but the scalar mass \(m_0\) is poorly constrained. In the wino-LSP case, \(m_{3/2}\) is constrained to about \(900\,\, \mathrm {TeV}\) and \(m_{\tilde{\chi }^0_{1}}\) to \(2.9\pm 0.1\,\, \mathrm {TeV}\), whereas in the Higgsino-LSP case \(m_{3/2}\) has just a lower limit \(\gtrsim 650\,\, \mathrm {TeV}\) (\(\gtrsim 480\,\, \mathrm {TeV}\)) and \(m_{\tilde{\chi }^0_{1}}\) is constrained to \(1.12 ~(1.13) \pm 0.02\,\, \mathrm {TeV}\) in the \(\mu >0\) (\(\mu <0\)) scenario. In neither case can the anomalous magnetic moment of the muon, \((g-2)_\mu \), be improved significantly relative to its Standard Model (SM) value, nor do flavour measurements constrain the model significantly, and there are poor prospects for discovering supersymmetric particles at the LHC, though there are some prospects for direct DM detection. On the other hand, if the \(\tilde{\chi }^0_{1}\) contributes only a fraction of the cold DM density, future LHC Open image in new window -based searches for gluinos, squarks and heavier chargino and neutralino states as well as disappearing track searches in the wino-like LSP region will be relevant, and interference effects enable \(\mathrm{BR}(B_{s, d} \rightarrow \mu ^+\mu ^-)\) to agree with the data better than in the SM in the case of wino-like DM with \(\mu > 0\). 相似文献
130.
Uzma Habib Amin Badshah Ulrich Flörke Rizwana Aleem Qureshi Bushra Mirza Nazar-ul-Islam Azeem Khan 《Journal of chemical crystallography》2009,39(10):730-734
Abstract The reaction of Cu(OOCCH3)2·H2O with (2,4-diamino-5-(3′,4′,5′-trimethoxybenzyl) pyrimidine (trimethoprim) in ethanolic solution at 80 °C affords the title
complex which has been characterized by elemental, IR, and NMR (1H and 13C).The crystal structure has been determined by single crystal X-ray diffraction. Compound 1 (C36H48Cu2N8O14) is triclinic, space group P-1 with a = 7.2676(4) ?, b = 11.6721(7) ?, c = 12.8279(8) ?, α = 95.839(1)°, β = 93.456(1)°, γ = 105.541(1)°, Z = 1. Two copper atoms are coordinated directly to each other as well as are held together by four bridging aceto groups.
Each copper atom is also bonded opposite the Cu–Cu vector to a trimethoprim molecule through the N(1) atom of the pyrimidine
ring. Trimethoprim acts as a monodentate ligand through the pyrimidine nitrogen N(1) atom. The complex was screened for the
activity against several bacteria, showing more activity against bacteria as compared to trimethoprim.
Graphical Abstract To enhance the activity of trimethoprim, its derivative was prepared and there bacterial activity against several bacteria
was analyzed.
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