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31.
Multiresidue analysis of multiclass plant growth regulators in grapes by liquid chromatography/tandem mass spectrometry 总被引:1,自引:0,他引:1
Oulkar DP Banerjee K Ghaste MS Ramteke SD Naik DG Patil SB Jadhav MR Adsule PG 《Journal of AOAC International》2011,94(3):968-977
A selective and rapid multiresidue analysis method is presented for simultaneous estimation of 12 plant growth regulators (PGRs), namely, auxins (indol-3-acetic acid, indol-3-butyric acid, and naphthyl acetic acid), cytokinins (kinetin, zeatin, and 6-benzyladenine), gibberellic acid (GA3), abscisic acid, and synthetic compounds, namely, forchlorfenuron, paclobutrazole, isoprothiolane, and 2,4-dichlorophenoxy acetic acid (2,4-D) in bud sprouts and grape berries at the development stages of 2-3 and 6-8 mm diameters, which are the critical phases when exogenous application of PGRs may be necessary to achieve desired grape quality and yield. The sample preparation method involved extraction of plant material with acidified methanol (50%) by homogenization for 2 min at 15000 rpm. The pH of the extract was enhanced up to 6 by adding ammonium acetate, followed by homogenization and centrifugation. The supernatant extract was cleaned by SPE on an Oasis HLB cartridge (200 mg, 6 cc). The final extract was measured directly by LC/MS/MS with electrospray ionization in positive mode, except for 2,4-D, GA3, and abscisic acid extracts, which required analysis in negative mode. Quantification by multiple reaction monitoring (MRM) was supported with full-scan mass spectrometric confirmation using "information-dependent acquisition" triggered with MRM to "enhanced product ionization" mode of the hybrid quadrupole-ion trap mass analyzer. The LOQ of the test analytes varied between 1 and 10 ng/g with associated recoveries of 80-120% and precision RSD <25% (n = 8). Significant matrix-induced signal suppression was recorded when the responses for pre- and postextraction spikes of analytes were compared; this could be resolved by using matrix-matched calibration standards. The method could successfully be applied in analyzing incurred residue samples and would, therefore, be useful in precisely deciding the necessity and dose of exogenous applications of PGRs on the basis of measured endogenous levels. 相似文献
32.
Thaksen Jadhav Yuan Fang William Patterson Cheng‐Hao Liu Ehsan Hamzehpoor Dmitrii F. Perepichka 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(39):13891-13895
Designing structural order in electronically active organic solids remains a great challenge in the field of materials chemistry. Now, 2D poly(arylene vinylene)s prepared as highly crystalline covalent organic frameworks (COFs) by base‐catalyzed aldol condensation of trimethyltriazine with aromatic dialdehydes are reported. The synthesized polymers are highly emissive (quantum yield of up to 50 %), as commonly observed in their 1D analogues poly(phenylene vinylene)s. The inherent well‐defined porosity (surface area ca. 1000 m2 g?1, pore diameter ca. 11 Å for the terephthaldehyde derived COF‐1) and 2D structure of these COFs also present a new set of properties and are likely responsible for the emission color, which is sensitive to the environment. COF‐1 is highly hydrophilic and reveals a dramatic macroscopic structural reorganization that has not been previously observed in framework materials. 相似文献
33.
Satish N. DigheHemant R. Jadhav 《Tetrahedron letters》2012,53(43):5803-5806
Microwave assisted simple, rapid, solventless, and catalyst-free chemoselective method for the protection of amino group in aromatic, aliphatic, heterocyclic, aralkyl amines, phenyl hydrazine, and amino acid esters in good to excellent isolated yield (83-98%) in short reaction time (2-12 min) has been reported. 相似文献
34.
An efficient and eco-friendly procedure for the synthesis of 2-amino-5-oxo-4-aryl-4H,5H-pyrano[3,2-c]chromene-3-carboxamide has been developed through a one-pot three-component condensation of 4-hydroxycoumarin with aldehydes and cyanoacetamide, in the presence of catalytic amount of polystyrene-supported p-toluenesulfonic acid (PS-PTSA) as a highly active and reusable heterogeneous acid catalyst in EtOH at 80?°C conditions. This new procedure offers several advantages such as shorter reaction times, excellent yields, a wide range of functional group tolerance, easy experimental work-up procedure, operationally simple under metal-free reaction conditions and C-C/C-O bond formation. The catalyst can be recovered and reused for at least four runs without any significant impact on the product yields. 相似文献
35.
Swapnil R. Sarda Jagpal D. Kale Sunil K. Wasmatkar Vijay S. Kadam Pravin G. Ingole Wamanrao N. Jadhav Rajendra P. Pawar 《Molecular diversity》2009,13(4):545-549
Chalcones on condensation with malononitrile and ammonium acetate in the presence of ionic liquid ethylammonium nitrate affords
the corresponding 2-amino-4, 6-diphenylpyridine-3-carbonitrile in excellent yield. The ionic liquid is recycled and reused
several times. 相似文献
36.
37.
A convenient and highly efficient method for the synthesis of novel polyheterocyclic chromeno pyrimido[1,2-b]indazolone derivatives via a three-component condensation of 1H-indazol-3-amine, aldehydes and 4-hydroxycoumarin catalyzed by Bronsted acid ionic liquid [Et3NH][HSO4] under solvent-free reaction conditions is presented. This ionic liquid is air and water stable and easy to prepare from amine and acid. The main advantages of this protocol includes short reaction time, excellent yield, easy work-up, operational simplicity, a wide range of functional group tolerance and column chromatography-free method. The catalyst can be recovered and reused for at least four runs without any significant impact on the product yields. 相似文献
38.
G. Saravanan M. V. Suryanarayana Manoj J. Jadhav M. Ravikumar N. Someswararao P. V. R. Acharyulu 《Chromatographia》2007,66(5-6):435-438
This present work narrates the stress stability behavior and development of a liquid chromatographic method for the quantitative
determination of anastrozole. Anastrozole is appropriately used when using substantial amounts of aromatizing steroids, or
when one is prone to gynecomastia and using moderate amounts of such steroids. A chromatographic separation was achieved on
a Hichrom RPB18 (250 × 4.6 mm, 5 μ) column using water and mixture of acetonitrile and methanol (1:1 ratio) as mobile phase.
Forced degradation studies were performed on bulk samples of anastrozole using acid, base, hydrogen peroxide, heat and UV
light. Degradation of the drug substance was observed in base hydrolysis. Degradation product formed under base hydrolysis
was found to be Imp-C. The sample solution and mobile phase were found to be stable up to 48 h. The developed method was validated
with respect to linearity, accuracy, precision, robustness and forced degradation studies prove the stability indicating power
of the method. 相似文献
39.
Herein, we report the controlled and direct fabrication of Cu2O/CuO thin film on the conductive nickel foam using electrodeposition route for the electrochemical reduction of carbon dioxide (CO2) to methanol. The electrocatalytic reduction was performed in CO2 saturated aqueous solution consisting of KHCO3, pyridine and HCl at room temperature. CO2 reduction was carried out at a constant potential of −1.3 V for 120 min to study the electrochemical performance of the prepared electrocatalysts. Cu2O/CuO shows better electrocatalytic activity with highest current density of 46 mA/cm2. The prepared catalyst can be an efficient and selective electrode for the production of methanol. 相似文献
40.
Amol Maruti Jadhav Sandip Gangadhar Balwe Jong Su Kim Kwon Taek Lim Yeon Tae Jeong 《Tetrahedron letters》2019,60(7):560-565
An efficient, inexpensive and environmentally friendly synthesis of novel 3-amino-2-benzoyl-1-aryl-1H-pyrazolo[1,2-b]phthalazine-5,10-dione and 3-amino-2-benzoyl-1-aryl-1H-pyrazolo[1,2-a]pyridazine-5,8-dione derivatives has been developed via one-pot three-component reaction of phthalhydrazide or maleic hydrazide, aldehydes and arylacetonitrile in the presence of catalytic amount of InCl3 as a Lewis acid catalyst under solvent-free conditions. The most important features of the present protocol are mild reaction conditions, short reaction times, high yields, and a wide range of functional group tolerance. 相似文献