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261.
S. Sundaram P. Subhasri T. R. Rajasekaran R. Jayaprakasam T. S. Senthil V. N. Vijayakumar 《Brazilian Journal of Physics》2017,47(4):382-392
Hydrogen-bonded liquid crystal (HBLC) is synthesized from citric acid (CA) and 4-(octyloxy)benzoic acid (8OBA) with different mole ratios. Fourier transform infrared spectroscopy (FT-IR) confirms the presence of hydrogen bond between CA and 8OBA. Nuclear magnetic resonance (NMR) spectroscopic studies validate the intermolecular complementary, cyclic type of hydrogen bond, and molecular environment in the designed HBLC complex. Powder X-ray diffraction analysis reveals the monoclinic nature of liquid crystal complex in solid phase. Liquid crystal parameters such as phase transition temperature and enthalpy values for the corresponding mesogenic phases are investigated using a polarizing optical microscope (POM) and differential scanning calorimetry (DSC). It is observed that the change in chain length and steric hindrance while increasing the mole ratio in HBLC complex induces a new smectic X (Sm X) along with higher-order smectic G (Sm G) phases by quenching of smectic C (Sm C). From the experimental observations, induced Sm X phase has been identified as a finger print texture. Also, Sm G is a multi-colored mosaic texture in 1:1, 1:2, and 1:3 mol ratios. The optical tilt angle, thermal stability factor, and enhanced thermal span width of CA + 8OBA complex are discussed. 相似文献
262.
Kumaran Ramanathan Juraj Svitel Anatoli Dzgoev P. V. Sundaram Bengt Danielsson 《Applied biochemistry and biotechnology》2001,96(1-3):287-301
Molecular electronics involves expertise from several branches of science. Various biomaterials and electronics are involved
in the fabrication of such devices. While passive biomaterials are involved in anchoring the active biomolecules, the latter
are involved in switching and/or signal transduction. In the present investigation we have used a glass-capillary-based approach
to design a biosensor for retinol. The sensing element is retinol-binding protein (RBP). The affinity of retinoic-acid-horseradish
peroxidase (conjugate) to RBP is tested using a surface plasmon resonance technique. A simple photomultiplier-tube-based system
is exploited to monitor the chemiluminescent signal generated upon reaction of hydrogen peroxide and luminol with the conjugate
bound to RBP. The photomultiplier tube is directly coupled to a computer for data logging. 相似文献
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264.
Maury Suresh Kumar Kumar Dhirendra Kamal Arsala Singh Himanshu Kumar Kumari Savita Singh Sundaram 《Molecular diversity》2021,25(1):131-142
Molecular Diversity - A facile and efficient multicomponent synthesis of benzodiazepine ring in water under ultrasound irradiation is reported first time. The current procedure escapes traditional... 相似文献
265.
Verma Pratibha Chauhan Swati Singh Vishal Singh Sundaram Srivastava Vandana 《Molecular diversity》2022,26(3):1769-1777
A novel multicomponent one-pot expeditious synthesis of highly functionalized and pharmaceutically fascinated pyranopyrazoles has been developed. This reaction occurs via tandem Knoevenagel condensation reaction of methyl aryl derivatives, 3-methyl pyrazolone and malononitrile in the presence of urea hydrogen peroxide under the physical grinding method. The present methodology offers several benefits such as available green and cheap starting materials, solvent-free, mild reaction conditions, high atom economy, eco-friendly standards, excellent yields and easy isolation of the products without column chromatographic separation.
Graphic abstract266.
267.
Harihara Subramanian Sundaram Dhamodharan Raghavachari 《Journal of polymer science. Part A, Polymer chemistry》2012,50(5):996-1007
Controlled and very rapid ambient temperature polymerization of tert‐butyl acrylate (tBA) via atom transfer radical polymerization (ATRP) and single electron transfer living radical polymerization (SET‐LRP) conditions is reported. Two initiators, one that would generate a secondary radical and another that would generate a primary radical, upon activation, are used. A very active catalyst CuBr/Me6TREN was found to initiate rapid polymerization whether it was the primary or the secondary initiator. The polymerization was well controlled and very rapid. The initiator that produces secondary initiating site is found to result in more rapid polymerization than the one that produces primary initiating site. To explore the possibility of rapid ambient temperature polymerization through the SET‐LRP mechanism, the polymerization was also carried out in the presence of DMSO. It was found that the polymerization was much faster compared to the bulk ATRP, without loss of control. Styrene was block copolymerized from PtBA macroinitiators and vice versa. In both the cases, block copolymers with controlled molecular weights were obtained. The tBA block of the polymer was selectively hydrolyzed to get amphiphilic block copolymers. This amphiphilic block copolymer was found to be useful in preparing stable cadmium sulfide (CdS) nanoparticulate dispersion. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
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