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61.
Yae Eun Chong Manting Chiang Kiran Deshpande Simon Haroutounian Leonid Kagan Jong Bong Lee 《Biomedical chromatography : BMC》2019,33(11)
Ondansetron, a widely used antiemetic agent, is a P‐glycoprotein (P‐gp) substrate and therefore expression of P‐gp at the blood–brain barrier limits its distribution to the central nervous system (CNS), which was observed to be reversed by coadministration with P‐gp inhibitors. Tariquidar is a potent and selective third‐generation P‐gp inhibitor, and coadministration with ondansetron has shown improved ondansetron distribution to the CNS. There is currently no reported bioanalytical method for simultaneously quantifying ondansetron with a third‐generation P‐gp inhibitor. Therefore, we aimed to develop and validate a method for ondansetron and tariquidar in rat and human plasma samples. A full validation was performed for both ondansetron and tariquidar, and sample stability was tested under various storage conditions. To demonstrate its utility, the method was applied to a preclinical pharmacokinetic study following coadministration of ondansetron and tariquidar in rats. The presented method will be valuable in pharmacokinetic studies of ondansetron and tariquidar in which simultaneous determination may be required. In addition, this is the first report of a bioanalytical method validated for quantification of tariquidar in plasma samples. 相似文献
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63.
Yi-Hao Huang Chung-Cheng Chiang Yet-Pole I Chuen-Tzay Kuo Sheng-Hung Wu Jyh-Ping Hsu Jean-Claude Charpentier 《Journal of Thermal Analysis and Calorimetry》2013,114(3):1225-1229
This article covers the incompatible properties of nitric acid (HNO3) with formic acid (CH2O2), and more generally with various acids such as sulfuric acid (H2SO4), hydrochloric acid (HCl), and acetic acid (C2H4O2). Differential scanning calorimetry (DSC) was employed to determine the thermal hazard such as heat of decomposition (ΔH d), exothermic onset temperature (T 0), etc., in various acids. T 0 of HNO3 and CH2O2 were determined as 50 °C using DSC. Thus it has been observed that HNO3 mixed with CH2O2 should be prohibited during transportation, storage, and use. And more generally, process safety engineers and operator must take care to handle tanker and storage tank of typical acids in the transportation, storage, and manufacturing process. It is clear that there exists a need to follow and enforce in the chemical industries safety data sheets, globally harmonized system of classification and labeling of chemicals of United Nations (UN), education of safety and health, emergency response system, and process safety management. It is the aim of the present study concerning HNO3 with various acids. 相似文献
64.
C. L. Kuo T. L. Tsai A. C. Chiang K. S. Chang-Liao J. H. Chao 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(1):465-473
The purpose of this study is to develop a neutron activation method to determine trace amounts of 129I in cement-solidified radwastes. The radwaste samples were alkaline fused using KOH and then 129I and iodine carrier were chemically separated by solvent extraction before and after neutron irradiation. Both stable iodine (127I) and 129I can be activated by neutrons through 127I (n, 2n) 126I and 129I (n, γ) 130I reactions; their activated radionuclides were counted together with a high-purity germanium detector. The chemical recovery yields ranged from 30 to 60 %, and it was found that more than 99.9 % of interfering radionuclides can be removed using solvent extraction after neutron irradiation. The minimum detectable amounts can be lowered to less than 1 mBq g?1, which is superior to low energy γ-ray spectrometry by a factor of >102, on average. The established technique can be applied to re-evaluation of 129I content in radwastes that can be re-classified to lower classes, and the cost for designing a final disposal facility can be significantly reduced. 相似文献
65.
66.
Wu Qiyang Huang Tianyang Xia Songyan Otto Frank Lee Tzong-Yi Huang Hsien-Da Chiang Ying-Chih 《Journal of computer-aided molecular design》2022,36(7):537-547
Journal of Computer-Aided Molecular Design - When employing molecular dynamics (MD) simulations for computer-aided drug design, the quality of the used force fields is highly important. Here we... 相似文献
67.
Wang XL Yuan CZ Shen CP Wang P Adachi I Aihara H Arinstein K Aushev T Bakich AM Barberio E Bedny I Bhardwaj V Bitenc U Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chen A Chen KF Cheon BG Chiang CC Chistov R Cho IS Choi SK Choi Y Dalseno J Danilov M Dash M Drutskoy A Eidelman S Epifanov D Gabyshev N Go A Gokhroo G Ha H Hayasaka K Hayashii H Hazumi M Heffernan D Hoshi Y Hou WS Hyun HJ Iijima T Inami K Ishikawa A Ishino H Itoh R Iwasaki Y Kah DH Kang JH Kawai H Kawasaki T 《Physical review letters》2007,99(14):142002
The cross section for e+ e- --> pi+ pi- psi(2S) between threshold and sqrt[s]=5.5 GeV is measured using 673 fb(-1) of data on and off the Upsilon(4S) resonance collected with the Belle detector at KEKB. Two resonant structures are observed in the pi+ pi- psi(2S) invariant-mass distribution, one at 4361 +/- 9 +/- 9 MeV/c2 with a width of 74 +/- 15 +/- 10 MeV/c2, and another at 4664 +/- 11 +/- 5 MeV/c2 with a width of 48 +/- 15 +/- 3 MeV/c2, if the mass spectrum is parametrized with the coherent sum of two Breit-Wigner functions. These values do not match those of any of the known charmonium states. 相似文献
68.
We show how the forbidden bands of a Bragg reflector may shrink to points and how some classes of the guided modes of a planar Bragg waveguide may disappear altogether by shrinking with the forbidden bands. We derive the general conditions to determine the missing modes and explain these conditions with examples. It is possible, for example, to design a Bragg waveguide that rejects all antisymmetric modes and supports only symmetric modes for the TE polarization. We also highlight the effect of Brewster incidence on the interpretation of the missing modes for the TM polarization. 相似文献
69.
Jiann-Jyh Huang Yu-Hsiang Lin Chun-Liang Lai Sheng-Chuan Yang Shu Fu Lin Ju-Ying Yang Hung-Jyun Huang Chiawei Liu Win-Yin Wei Shih-Hsien Chuang Chao-Cheng Chiang Ying-Shuen E. Lee Chu-Bin Liao Ching Yuh Chern 《中国化学会会志》2020,67(3):422-429
In this study, we reported the inhibition profiles of 4′-acylpyrrole–5-fluoroindolin-2-one 3 with a C-3′ side chain for VEGFR2, PDGFR-β, and FGFR-1 protein kinases. The pyrrole-fused cyclohexanone moiety provided 3 with the best potency to inhibit the three kinases, and the C-3′ side chains contributed to the different inhibition profiles of 3 . Compound 3b with a C-3′ 2-carboxylethyl side chain showed good potency for the three kinase (IC50: 25–260 nM), and compound 3g with a N,N-dialkyl-2-carbamoylethyl side chain was more active for VEGFR2 (IC50: 59 nM) and PDGFR-β (IC50: 16 nM) than FGFR-1 (IC50: 1.7 μM). The C-3′ 3-(dialkylamino)propyl side chain accomplished 3h – j as selective PDGFR-β inhibitors (IC50: 7.8–13 nM). Compound 3b was further investigated and found potent to inhibit VEGF- and FGF-dependent cell proliferation with moderate in vivo anticancer activity. Results from docking simulations revealed that the interactions of 3b with VEGFR2 and FGFR-1 which could account for the different inhibition profiles of 3 . 相似文献
70.
The effects of group-delay difference in an active nonlinear long-period fiber grating (LPFG) made in an erbium-doped amplifying fiber (EDF) are investigated by proposing a general model that include the effects of detuning, group-delay difference, gain saturation, gain bandwidth and Kerr nonlinearity. In particular, we observe a new feature caused by the interaction between the group-delay difference and the gain bandwidth: the pulse breakup effect due to the group-delay difference can be suppressed by the finite bandwidth of the linear gain. 相似文献