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61.
62.
Simultaneous quantification of atenolol and chlorthalidone in human plasma by ultra‐performance liquid chromatography–tandem mass spectrometry 下载免费PDF全文
Jaivik V. Shah Daxesh P. Patel Priyanka A. Shah Mallika Sanyal Pranav S. Shrivastav 《Biomedical chromatography : BMC》2016,30(2):208-216
A simple, sensitive and reproducible ultra‐performance liquid chromatography–tandem mass spectrometry method has been developed for the simultaneous determination of atenolol, a β‐adrenergic receptor‐blocker and chlorthalidone, a monosulfonamyl diuretic in human plasma, using atenolol‐d7 and chlorthalidone‐d4 as the internal standards (ISs). Following solid‐phase extraction on Phenomenex Strata‐X cartridges using 100 μL human plasma sample, the analytes and ISs were separated on an Acquity UPLC BEH C18 (50 mm × 2.1 mm, 1.7 µm) column using a mobile phase consisting of 0.1% formic acid–acetonitrile (25:75, v/v). A tandem mass spectrometer equipped with electrospray ionization was used as a detector in the positive ionization mode for both analytes. The linear concentration range was established as 0.50–500 ng/mL for atenolol and 0.25–150 ng/mL for chlorthalidone. Extraction recoveries were within 95–103% and ion suppression/enhancement, expressed as IS‐normalized matrix factors, ranged from 0.95 to 1.06 for both the analytes. Intra‐batch and inter‐batch precision (CV) and accuracy values were 2.37–5.91 and 96.1–103.2%, respectively. Stability of analytes in plasma was evaluated under different conditions, such as bench‐top, freeze–thaw, dry and wet extract and long‐term. The developed method was superior to the existing methods for the simultaneous determination of atenolol and chlorthalidone in human plasma with respect to the sensitivity, chromatographic analysis time and plasma volume for processing. Further, it was successfully applied to support a bioequivalence study of 50 mg atenolol + 12.5 mg chlorthalidone in 28 healthy Indian subjects. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
63.
Ovender Singh Priyanka Gupta Anshu Singh Ankur Maji Udai P. Singh Kaushik Ghosh 《应用有机金属化学》2019,33(5)
Hexacoordinated non‐heme iron complexes [FeII(L1)2](ClO4)2 ( 1 ) and [FeII(L2)2](PF6)2 ( 2 ) have been synthesized using ligands L1 = (E)‐2‐chloro‐6‐(2‐(pyridin‐2ylmethylene) hydrazinyl)pyridine and L2 = (E)‐2‐chloro‐6‐(2‐(1‐(pyridin‐2‐yl)ethylidene)hydrazinyl) pyridine]. These complexes are highly active non‐heme iron catalysts to catalyze the C (sp3)?H bonds of alkanes. These iron complexes have been characterized using ESI?MS analysis and molecular structures were determined by X‐ray crystallography. ESI ? MS analysis also helped to understand the generation of intermediate species like FeIII?OOH and FeIV=O. DFT and TD?DFT calculations revealed that the oxidation reactions were performed through high‐valent iron center and a probable reaction mechanism was proposed. These complexes were also utilized for the degradation of orange II and methylene blue dyes. 相似文献
64.
Priyanka Lohar Manish Kumar Sharma Amit Kumar Sahu Rajeswari Rathod Pinaki Sengupta 《Biomedical chromatography : BMC》2019,33(12)
The combination of acebrophylline (ABP), levocetirizine (LCZ) and pranlukast (PRN) is used to treat allergic rhinitis, asthma, hay‐fever and other conditions where patients experience difficulty in breathing. This study was carried out with the aim of developing and validating a reverse‐phase high‐performance liquid chromatographic bioanalytical method to simultaneously quantitate ABP, LCZ and PRN in rat plasma. The objective also includes determination of the pharmacokinetic interaction of these three drugs after administration via the oral route after individual and combination treatment in rat. Optimum resolution between the analytes was observed with a C18 Kinetex column (250 mm × 4.6 mm × 5 μm). The chromatography was performed in a gradient elution mode with a 1 mL/min flow rate. The calibration curves were linear over the concentration range of 100–1600 ng/mL. The intra‐ and inter‐day precision and accuracy were found to be within acceptable limits as specified in US Food and Drug Administration guideline for bioanalytical method validation. The analytes were stable on the bench‐top (8 h), after three freeze–thaw cycles, in the autosampler (8 h) and as a dry extract (?80°C for 48 h). The statistical results of the pharmacokinetic study in Sprague–Dawley rats showed a significant change in pharmacokinetic parameters for PRN upon co‐administration of the three drugs. 相似文献
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66.
Kapil Mohan Saini Rakesh K. Saunthwal Sushmita Akhilesh K. Verma 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(5):1017-1021
Transition-metal-free regioselective synthesis of functionalized amino-indenones by the reaction of ortho-alkynylaldehydes with a broad range of primary amines by intramolecular cyclization has been described. The designed reaction proceeds through KOH-mediated Prins-type cyclization and DMSO-promoted oxidation of the cyclopent-2-en-1-one system. The proposed mechanism and role of solvent were well supported by control experiments. For the first time, we have disclosed the reverse reactivity of (2-alkynyl)-arylaldimines in a super basic system. 相似文献
67.
Singh Swati Bawitlung Laldingngheti Singh Munmun Kumar Chauhan Amit Padalia Rajendra Chandra Pal Anirban Verma Ram Swaroop 《Chemistry of Natural Compounds》2022,58(1):161-162
Chemistry of Natural Compounds - 相似文献
68.
NMR is a fast method for obtaining a holistic snapshot of the metabolome and also offers quantitative information without separating the compounds present in a complex mixture. Identification of the metabolites present in a plant extract sample is a crucial step for all plant metabolomics studies. In the present work, we used various two dimensional (2D) NMR methods such as J-resolved NMR, total correlation spectroscopy (TOCSY), and heteronuclear single quantum coherence sensitivity enhanced NMR spectroscopy for the identification of 36 common metabolites present in Coriandrum sativum L. seed extract. The identified metabolites belong to the following classes: organic acids, amino acids, and carbohydrates. 1H NMR spectra of such complex mixtures in general display tremendous signal overlap due to the presence of a large number of metabolites with closely resonating multiplet signals. This signal overlapping leads to ambiguity in an assignment, and hence, identification of metabolites becomes tedious or impossible in many cases. Therefore, the utility of pure-shift proton spectrum along the indirect (F1) dimension of the F1-PSYCHE-TOCSY spectrum is demonstrated for overcoming ambiguity in assignment of metabolites in crowded spectral regions from Coriandrum sativum L. seed extract sample. Because pure-shift NMR methods yield ultrahigh resolution spectrum (i.e., a singlet peak per chemical site) along one or more dimensions, such spectra provide better identification of metabolites compared with regular 2D TOCSY where signal overlap and peak distortions lead to ambiguity in the assignment. Nine metabolites were unambiguously assigned by pure-shift F1-PSYCHE-TOCSY spectrum, which was unresolved in regular TOCSY spectrum. 相似文献
69.
Dwivedi Jyotsana Gupta Abhishek Verma Shikhar Paliwal Sarvesh Rawat Ajay Kumar Singh 《平面色谱法杂志一现代薄层色谱法》2019,32(2):103-108
JPC – Journal of Planar Chromatography – Modern TLC - A high-performance thin-layer chromatography (HPTLC) method for the simultaneous quantitative determination and validation of... 相似文献
70.
Poojali P. Warekar Priyanka T. Patil Kirti T. Patil Dattatraya K. Jamale Govind B. Kolekar 《合成通讯》2016,46(24):2022-2030
An ecofriendly route has been investigated for the synthesis of 4-(4-nitro-phenyl)-2-phenyl-1,4-dihydro-benzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxylic acid ethyl ester derivatives by one-pot, three-component condensation of ethyl benzoylacetate, aromatic aldehydes, and 2-amino benzimidazole using 260?mol% of citric acid as reaction mediator. Citric acid is an inexpensive, nontoxic, and green medium with smoothly activates the rate of reaction. The synthesized compounds were assessed for in vitro antimycobacterial activity against Mycobacterium tuberculosis H37RV strain using the microplate alamar blue assay (MABA). The results indicate that among all the synthesized compound series, P-4 and P-9 compounds illustrate effective activity with a minimum inhibitory concentration of 25?µg/ml. 相似文献