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201.
Thin films of spinel LiMn2O4 have been fabricated using a metallorganic precursor. Crystalline films have been deposited on Au substrates to exhibit as
the cathode in rechargeable thin film lithium batteries. The nucleation and growth of spinel LiMn2O4 crystallites were investigated with heat treatment of the deposited thin films. Film capacity density as high as 22 μAh/cm2 was measured for LiMn2O4. The film heat treated at 700 °C were cycled electrochemically up to 30 cycles against Li metal without any degradation of
the capacity. There were neither open area nor amorphous layers which prevent the Li+ions transfer at the boundaries in the LiMn2O4 thin film. The microscopic study revealed that (111) planes in the two grains directly bonded at the grain boundary which
could proceed the lithium ion intercalation or deintercalation smoothly. 相似文献
202.
203.
Harusawa S Kawamura M Araki L Taniguchi R Yoneyama H Sakamoto Y Kaneko N Nakao Y Hatano K Fujita T Yamamoto R Kurihara T Yamatodani A 《Chemical & pharmaceutical bulletin》2007,55(8):1245-1253
The (2R,5S)-trans- and (2S,5S)-cis-stereoisomers 1a and 1b of 4(5)-(5-aminotetrahydropyran-2-yl)imidazole, which have two chiral centers and adopt a stable chair conformation, were synthesized via cyclization of diol intermediates 7 using L-glutamine as the starting material. Their enantiomers, (2S,5R)-trans-1c and (2R,5R)-cis-1d, were synthesized by the same methodology from D-glutamine. Stereo isomers 1a-d were converted into cyanoguanidines 11a-d, and into N-isopropyl and N-3,3-dimethylbutyl derivatives 12a-d and 13a-d, respectively. The results of in vivo brain microdialysis of the derivatives apparently indicated that only (2S,5R)-isomers increased the release of neuronal histamine. Among the many (2S,5R)-N-alkyl derivatives, 13c (OUP-133) and 18 (OUP-153) increased histamine release to 180-190% and 180-200% of basal levels, respectively, and were found to be novel histamine H(3) antagonists. 相似文献
204.
Yumi YamaguchiMariko Hashimoto Katsumi TohyamaMasanari Kimura 《Tetrahedron letters》2011,52(8):913-915
Pd/Et3B and Pd/Et2Zn systems promote the nucleophilic allylations of 2-aminotetrahydrofuran and 2-aminotetrahydropyran with allylic alcohols to provide ω-hydroxyhomoallylamines in high yields. The transformation is applicable to the allylation of non-protective carbohydrates, such as ribose and deoxyribose. 相似文献
205.
Ohyama K Shirasawa Y Wada M Kishikawa N Ohba Y Nakashima K Kuroda N 《Journal of chromatography. A》2004,1042(1-2):189-195
A novel packing material, 3-(4-sulfo-1,8-naphthalimido)propyl-modified silyl silica gel (SNAIP), was prepared for the use as a stationary phase of capillary electrochromatography (CEC). The sulfonic acid groups on SNAIP stationary phase contributed to the generation of electroosmotic flow (EOF) at low pH and served as a strong cation-exchanger. In CEC with SNAIP, a mixed-mode separation was predicted, comprising hydrophobic and electrostatic interactions as well as electrophoretic migration process. In order to understand the retention mechanism on SNAIP, effects of buffer pH, concentration, and mobile phase composition on EOF mobility and the retention factors of barbiturates and benzodiazepines were systematically investigated. Moreover, the retention behavior of barbiturates on SNAIP was investigated and compared with those on octadecyl silica (ODS), phenyl-bonded silica, and 3-(1,8-naphthalimido)propyl-modified silyl silica gel to confirm the presence of pi-pi interaction on its retention mechanism. It was observed that a column efficiency was more than 85,000 N/m for retained compounds and the relative standard deviations for the retention times of EOF marker, thiourea, and five barbiturates were below 2.5% (n = 4). Under an applied voltage of 20 kV and a mobile phase consisted of 5 mM phosphate (pH 3.8) and 40% methanol, the baseline separation of five barbiturates was achieved within 3 min. 相似文献
206.
Indolenines were generated at −78 °C from 3-benzylic or 3-allylic indoles by dehydrogenation with N-tert-butylbenzenesulfinimidoyl chloride, and a carbon-carbon bond was formed at −78 °C in a one-pot manner by treating these indolenines with various carbon nucleophiles such as active methylene compounds or organocuprates. 相似文献
207.
The well‐defined polystyrene‐block‐poly(4‐vinylpyridine) [PS‐block‐P4VP (SV1); lamellar morphology] and polyisoprene‐block‐poly(α‐methyl styrene) [PI‐block‐PMS (IMS1); PI spherical morphology] diblock copolymers were prepared by sequential anionic polymerization techniques. The segregated chains in the P4VP lamellar layers of the SV1 film (PS lamellae: 41 nm; P4VP lamellae: 51 nm) were crosslinked with 1,4‐dibromobutane. This crosslinked film was insoluble in organic solvents such as benzene and chloroform (CHCl3) and exhibited various structural colors under the swollen state. The IMS1 film (body‐centered cubic lattice, diameter of PI spheres: 53 nm) was soaked in the mixture of CHCl3/hexane (1 : 10, v/v). This solvent system resulted in the swelling of PI spherical domains. The transmitted and reflected light color through the swollen film changed to a deep blue. Such color changes were reversible upon swelling in solvent and evaporation of the solvent. Subsequently, photofunctional diethyldithiocarbamate (DC) groups were introduced into the PS block of the parent block copolymer IMS1 by means of polymer reactions. The locking of the cubic lattice was performed with living radical graft copolymerization from DC groups of swollen as‐cast film in methyl methacrylate (MMA) under UV irradiation. The locking of structural colors such as blue and green was also achieved, varying the content of poly(methyl methacrylate) (PMMA) grafted chains. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
208.
Masashi Ozaki Ai Shimazaki Mina Jung Yumi Nakaike Naoki Maruyama Shinya Yakumaru Alwani Imanah Rafieh Takahiro Sasamori Norihiro Tokitoh Piyasiri Ekanayake Yasujiro Murata Richard Murdey Atsushi Wakamiya 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(28):9489-9493
A high‐purity methylammonium lead iodide complex with intercalated dimethylformamide (DMF) molecules, CH3NH3PbI3?DMF, is introduced as an effective precursor material for fabricating high‐quality solution‐processed perovskite layers. Spin‐coated films of the solvent‐intercalated complex dissolved in pure dimethyl sulfoxide (DMSO) yielded thick, dense perovskite layers after thermal annealing. The low volatility of the pure DMSO solvent extended the allowable time for low‐speed spin programs and considerably relaxed the precision needed for the antisolvent addition step. An optimized, reliable fabrication method was devised to take advantage of this extended process window and resulted in highly consistent performance of perovskite solar cell devices, with up to 19.8 % power‐conversion efficiency (PCE). The optimized method was also used to fabricate a 22.0 cm2, eight‐cell module with 14.2 % PCE (active area) and 8.64 V output (1.08 V/cell). 相似文献
209.
210.
The hydrothermal reaction of fumaric acid, benzylamine, and metal salts yielded M[(rac-N-benzyl-Asp)(H(2)O)] (M = Co, Ni), 1 and 2, and Ni[(rac-N-benzyl-Asp)(H(2)O)(3)]·H(2)O 3. Under mild hydrothermal conditions, Michael addition of benzylamine to fumaric acid led to the formation of a racemic mixture of N-benzyl aspartic acid enantiomers. The noncentrosymmetric structures of 1 and 2 consist of one-dimensional polymeric chains in which metal cations are bridged by d- and l-N-benzyl aspartate anions alternating along the chain. The centrosymmetric structure of 3 is composed of discrete Ni[(rac-N-benzyl-Asp)(H(2)O)(3)] units that are connected by hydrogen bonds into layers. The single layers are homochiral but are hydrogen bonded to similar homochiral layers that contain the N-benzyl aspartate with the opposite handedness. Compounds 1 and 2 showed second harmonic generation (SHG), and their magnetic and thermodynamic properties are described. 相似文献