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901.
902.
Jin-Feng Kenji Aramaki Akihiro Ogawa Masahiko Tsukahara Hironobu Kunieda 《Journal of Dispersion Science and Technology》2013,34(1-3):29-36
Sodium (3-dodecanoyloxy-2-hydroxy-propyl) succinate (SLGMS) forms microemulsions by mixing with cosurfactants such as glycerol mono(2-ethylhexyl) ether (MEH), although the combination with ordinary cosurfactant such as hexanol does not form a microemulsion of large solubilization. The middle-phase microemulsion coexists with excess water and oil (octane) phases at an optimum-mixing fraction of SLGMS and MEH in the presence of salt. The monomeric solubility of MEH in oil is low and MEH is mainly combined with SLGMS at an oil—water interface inside microemulsions. With decreasing salinity, the three-phase body shrinks and eventually disappears. The three-phase body may be terminated at a tricritical point, at which three phases simultaneously coexist. The effect of type of oil on the solubilization capacity of the microemulsions is also discussed. 相似文献
903.
Makoto Kiso Yuji Ogawa Shinji Tanaka Hideharu Ishida Akira Hasegawa 《Journal of carbohydrate chemistry》2013,32(4):621-630
The diastereoisomeric pair of a biologically active, lipid A-subunit analogs named in the title have been synthesized, starting from 2-amino-l,5-anhydro-2-deoxy-4,6-0-isopropylidene-D-glucitol and optically active 3-hydroxytetradecanoic acid. 相似文献
904.
Akira Hasegawa Masayuki Ogawa Hideharu Ishida Makoto Kiso 《Journal of carbohydrate chemistry》2013,32(4):393-414
ABSTRACT Coupling of the primary hydroxyl group in the suitably protected 2-(trimethylsilyl)ethyl glycosides of D-glucopyranose (3), N-acetyl-D-glucosamine (7), N-acetyl-D-galactosamine (9), D-lactose (10), and N-acetylneuraminic acid (11), with methyl (methyl 5-acetamido-4, 7,8, 9-tetra-O-acetyl-3, 5-dideoxy-2-thio-D-glycero-α-D-galacto-2-nonulopyranosid)onate (12) as the glycosyl donor in acetonitrile in the presence of dimethyl(methylthio)sulfonium triflate (DMTST) as a glycosyl promoter and molecular sieves 3A, gave predominantly the corresponding α-glycosides 13, 15, 17, 25, and 29 of N-acetylneuraminic acid in 43-71% yields, respectively, together with the ß-glycosides (13-24%). 相似文献
905.
Kazuki Ogata Daisuke Sasano Tomoya Yokoi Dr. Katsuhiro Isozaki Ryota Yoshida Dr. Toshio Takenaka Dr. Hirofumi Seike Dr. Tetsuya Ogawa Prof. Dr. Hiroki Kurata Dr. Nobuhiro Yasuda Prof. Dr. Hikaru Takaya Prof. Dr. Masaharu Nakamura 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(37):12356-12375
The NCN‐pincer Pd‐complex‐bound norvalines Boc‐D /L ‐[PdCl(dpb)]Nva‐OMe ( 1 ) were synthesized in multigram quantities. The molecular structure and absolute configuration of 1 were unequivocally determined by single‐crystal X‐ray structure analysis. The robustness of 1 under acidic/basic conditions provides a wide range of N‐/C‐terminus convertibility based on the related synthetic transformations. Installation of a variety of functional groups into the N‐/C‐terminus of 1 was readily carried out through N‐Boc‐ or C‐methyl ester deprotection and subsequent condensations with carboxylic acids, R1COOH, or amines, R2NH2, to give the corresponding N‐/C‐functionalized norvalines R1‐D /L ‐[PdCl(dpb)]Nva‐R2 2 – 9 . The dipeptide bearing two Pd units 10 was successfully synthesized through the condensation of C‐free 1 with N‐free 1 . The robustness of these Pd‐bound norvalines was adequately demonstrated by the preservation of the optical purity and Pd unit during the synthetic transformations. The lipophilic Pd‐bound norvalines L ‐ 2 , Boc‐L ‐[PdCl(dpb)]Nva‐NH‐n‐C11H23, and L ‐ 4 , n‐C4H9CO‐L ‐[PdCl(dpb)]Nva‐NH‐n‐C11H23, self‐assembled in aromatic solvents to afford supramolecular gels. The assembled structures in a thermodynamically stable single crystal of L ‐ 2 and kinetically stable supramolecular aggregates of L ‐ 2 were precisely elucidated by cryo‐TEM, WAX, SAXS, UV/Vis, IR analyses, and single‐crystal X‐ray crystallography. An antiparallel β‐sheet‐type aggregate consisting of an infinite one‐dimensional hydrogen‐bonding network of amide groups and π‐stacking of PdCl(dpb) moieties was observed in the supramolecular gel fiber of L ‐ 2 , even though discrete dimers are assembled through hydrogen bonding in the thermodynamically stable single crystal of L ‐ 2 . The disparate DSC profiles of the single crystal and xerogel of L ‐ 2 indicate different thermodynamics of the molecular assembly process. 相似文献
906.
907.
This critical review introduces a discussion on the influence of preparative procedures (nanofabrication) of nanostructured hybrids and biohybrids, comparing their structural and textural characteristics that determine the properties of the resulting materials. Selected examples of silicate-based hybrids of analogous compositions prepared by both molecular and blocks-assembly bottom-up strategies are discussed to show advantages and inconveniences of each methodology (341 references). 相似文献
908.
In vitro-transcribed, unmodified, and non-aminoacylated amber suppressor tRNAs that are recognized by natural aminoacyl-tRNA synthetase were improved toward higher suppression efficiency in batch-mode cell-free translation in wheat germ extract. The suppression efficiency of the suppressor obtained through four sequence optimization steps (anticodon alteration of natural tRNAs (the first generation); chimerization of the efficient suppressors in the first generation; investigation and optimization of the effective parts in the second generation; combination of the optimized parts in the third generation) and by the terminal tuning was approximately 60%, which was 2.4-fold higher than that of the best suppressor in the first generation. In addition, an eRF1 aptamer further increased the efficiency up to 85%. This highly efficient suppression system also functioned well in a dialysis-based large-scale protein synthesis. 相似文献
909.
A multinuclear palladium catalyst can be used to realize the efficient catalytic asymmetric alkylative ring-opening reaction of oxabicyclic alkenes using dimethylzinc. The use of (R)-BINOL-PHOS bearing bisphosphine and diol moieties is essential for achieving excellent catalytic performance; the corresponding monophosphine and hydroxy-protected derivatives showed lower catalytic activities and/or enantioselectivities. The generation of Pd/Zn-multinuclear complexes is a key feature of the present catalysis. 相似文献
910.
Nakatake H Ekimoto H Aso M Ogawa A Yamaguchi A Suemune H 《Chemical & pharmaceutical bulletin》2011,59(6):710-713
Bisphosphonates have high affinity for hydroxyapatite (HA), which is abundantly present in bone. Also, platinum complexes are known that have a wide spectrum of antitumor activities. The conjugate of bisphosphonate and a platinum complex might have HA affinity and antitumor activity, and become a drug for metastatic bone tumor. In this study, the authors synthesized platinum complexes that had dialkyl bisphosphonic acid as a ligand, and evaluated the possibility of the synthesized complexes as a drug for metastatic bone tumor. The synthesized dialkyl bisphosphonate platinum(II) complex was characterized, and its stability in an aqueous solution was also confirmed. The synthesized platinum complex showed higher HA affinity than other platinum complexes such as cisplatin and carboplatin in an experiment of adsorption to HA. In vitro, the platinum complex showed tumor growth inhibitory effect stronger than or equal to cisplatin, which is the most commonly used antitumor agent. Moreover, the platinum complex showed a bone absorption inhibitory effect on the osteoclast. These results suggest potential of dialkyl bisphosphonate platinum(II) complexes as a drug for metastatic bone tumor. 相似文献