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81.
Masaaki Yoshifuji Katsuhiro Shibayama Ichiro Shima Naoki Inamoto 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):11-14
Abstract Some reactions of diphosphenes and the related species involving oxidation, reduction, alkylation, sulfurization, and 6η-coordination are described. 相似文献
82.
Masaaki Kubota Raul A. Reimer Kuniko Terajima Yuji Yoshimura Akio Nishijima 《Analytica chimica acta》1987
Inductively-coupled plasma/atomic emission spectrometry with a high-resolution vacuum scanning monochromator is described for the determination of sulfur at 180.734 nm. The behavior of the signal-to-background ratio is investigated as functions of RF power, argon gas flow rate and observation height above the load coil. Under the operating conditions selected, the detection limit is 3 μg l?1. The Se I 196.090-nm line is chosen as internal standard, because the S/Se line pair exhibited the least change with carrier gas flow rate and acid concentration of solution. Sulfur in NiMo and CoMo/ Al2O3 catalysts used for coal liquefaction is determined as S(II) and S(VI) species. The total amount of the species agreed well with the sulfur value obtained by the conventinal combustion method. 相似文献
83.
Carbazoledioxazines with an angular type structure (5,15-dialkyl-7,17-dialkyloxy-9,19-dichloro-5,15-dihydrodiindolo[2,3-c:2′,3′-n]triphenodioxazines) were selectively synthesized by electrochemical oxidative ring closure of precursors (2,5-bis(9-alkyl-2-alkyloxy-3-carbazolylamino)-3,6-dichloro-1,4-benzoquinones). The structure was confirmed by 1H-nmr and other instrumental analyses. Their thermal properties and solubilities were investigated and were compared with those of carbazoledioxazines with a linear type structure. 相似文献
84.
Masaaki Suzuki Yoshihumi Sato Hiroshi Akatsuka 《Plasma Chemistry and Plasma Processing》1996,16(3):399-415
The objective of the present work is to investigate the behavior of hydrogen in an atmospheric-pressure free-burning argon are when a small amount of hydrogen is added into the arc. A two-dimensional model calculation is carried out under the assumption that the ionization reaction of argon is in equilibrium and the reactions among hydrogen molecules, atoms, ions, and electrons are not necessarily in equilibrium. This calculation gives the following conclusion. The hydrogen mass fraction of 0.001 is too small to affect the flow and temperature fields markedly, and the concentration ratios among the hydrogen species are in equilibrium in the greater part of the arc region except for same parts with a steep temperature gradient. The hydrogen mass Junction, however, is not uniform in the me and, especially in the high-temperature region near the cathodes, over three dynes mass fraction of the hydrogen accumulates and flows downstream to cause a high flux of hydrogen atom toward the anode. This phenomena can be explained by the large difference between the diffusivity of hydrogen atom and that of hydrogen ion in argon ion. 相似文献
85.
86.
Lithium is an important element for lithium battery and clinical treatment of manic depression. Thus,rapid and accurate methods for the determination of lithium and its separation and collection of lithium in recycle are receiving a great concern. Because of the high concentrations of Na+ in sea water and blood, very high Li+/Na+ selectivity is required for the separation and determination of Li+ at concentration less than 10-4 M (700 ppb) in a large excess of Na+. We report here the methods of separation, transport and determination of lithium as low as 10-5 M (M=mol dm-3) in the presence of Na+ more than 0.1 M by using a water-soluble octabromoporphyrin; H2P4-) synthesized in our laboratory. 相似文献
87.
The reactions of sterically protected phosphaalkenes with some boron reagents, such as boron hydrides, were carried out leading to hydroboration products depending on the substrates and boron reagents. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 187–196, 1999 相似文献
88.
Chieko Kogawa Asuka Fujiwara Ryuta Sekiguchi Taku Shoji Jun Kawakami Masaaki Okazaki Shunji Ito 《Tetrahedron》2018,74(49):7018-7029
Azulene analog of tryptanthrin, azuleno[1′,2′:4,5]pyrrolo[2,1-b]quinazoline-6,14-dione, was successfully prepared by the condensation reaction of azuleno[2,1-b]pyrrole-2,3-dione with isatoic anhydride in the presence of sodium hydride or diisopropylethylamine (DIPEA). Its 2-halo derivatives were also obtained in high yields by the condensation reaction with 5-haloisatoic anhydrides in the presence of DIPEA. Reactivity toward electrophilic reagents was revealed by halogenation with N-bromosuccinimide (NBS) or N-iodosuccinimide (NIS) to afford 12-halo derivatives in high yields. Among the halo derivatives, 2-iodo and 12-iodo derivatives were reactive enough to afford phenylethynyl derivatives under Pd-catalyzed Sonogashira cross-coupling conditions. Within the phenylethynyl derivatives, only 12-phenylethynyl derivative was transformed into its 1,1,4,4-tetracyanobutadiene (TCBD) derivative by the reaction with TCNE. Amphoteric redox properties of the novel azulene analogs of tryptanthrin were characterized by spectroscopic and voltammetric analyses. 相似文献
89.
Dr. Tatsuki Kurokawa Dr. Shigeki Kiyonaka Dr. Eiji Nakata Dr. Masayuki Endo Shohei Koyama Emiko Mori Nam Ha Tran Huyen Dinh Dr. Yuki Suzuki Kumi Hidaka Dr. Masaaki Kawata Dr. Chikara Sato Prof. Hiroshi Sugiyama Prof. Takashi Morii Prof. Yasuo Mori 《Angewandte Chemie (International ed. in English)》2018,57(10):2586-2591
In native systems, scaffolding proteins play important roles in assembling proteins into complexes to transduce signals. This concept is yet to be applied to the assembly of functional transmembrane protein complexes in artificial systems. To address this issue, DNA origami has the potential to serve as scaffolds that arrange proteins at specific positions in complexes. Herein, we report that Kir3 K+ channel proteins are assembled through zinc‐finger protein (ZFP)‐adaptors at specific locations on DNA origami scaffolds. Specific binding of the ZFP‐fused Kir3 channels and ZFP‐based adaptors on DNA origami were confirmed by atomic force microscopy and gel electrophoresis. Furthermore, the DNA origami with ZFP binding sites nearly tripled the K+ channel current activity elicited by heterotetrameric Kir3 channels in HEK293T cells. Thus, our method provides a useful template to control the oligomerization states of membrane protein complexes in vitro and in living cells. 相似文献
90.
Md. Akhtaruzzaman Masaaki Tomura Yoshiro Yamashita 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):751-753
The title compound, C20H10N4S, and its dipyridinium salt, 4,4′‐(2,1,3‐benzodiazol‐4,7‐diyldiethynyl)dipyridinium diperchlorate, C20H12N4S2+·2ClO4?, display bond alternation in the 2,1,3‐benzothiadiazole rings, which suggests their quinonoid character. The dipyridinium dication molecules stack along the a axis and form a dimer with short S?N interheteroatom contacts [3.146 (4) Å] between the two 1,2,5‐thiadiazole rings. The dimer is surrounded by the perchlorate anions with which it forms a large number of intermolecular N—H?O and C—H?O hydrogen bonds. 相似文献