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91.
M. Yosoi H. Akimune I. Daito H. Ejiri H. Fujimura M. Fujiwara K. Hara K. Y. Hara T. Ishikawa M. Itoh Y. Itow T. Kawabata K. Kobayashi M. Nakamura T. Noro E. Obayashi H. Sakaguchi Y. Sakemi M. Shiozawa H. Takeda T. Taki A. Tamii H. Toyokawa N. Tsukahara M. Uchida T. Yamada Y. Yasuda H. P. Yoshida R. G. T. Zegers 《Physics of Atomic Nuclei》2004,67(10):1810-1817
Decay particles from the s-hole states in 11B and 15N have been measured in coincidence with the quasifree 12C(p, 2p) and 16O(p, 2p) reactions at E p =392 MeV. Triton decay is found to be dominant for the 11B(s-hole) state and also found to be larger than α decay for the 15N(s-hole) state despite its smaller Q value compared to α decay. Measured decay branching ratios are discussed in comparison with the results of statistical-model, SU(3)-model, and shell-model calculations. The energy spectra around the s-hole states in both 11B and 15N exhibit some bumplike structures, which can be qualitatively explained by recent shell-model calculations for both nuclei. 相似文献
92.
Bergman AC Benjamin T Alaiya A Waltham M Sakaguchi K Franzén B Linder S Bergman T Auer G Appella E Wirth PJ Jörnvall H 《Electrophoresis》2000,21(3):679-686
Two-dimensional gel electrophoresis with subsequent analysis by mass spectrometry was applied to study differences in protein expression between benign and malignant solid tumors from human beast, lung and ovary cells. Cells from freshly resected clinical material were lysed and the extracts were subjected to isoelectric focusing with immobilized pH gradients followed by second-dimensional separation on 10-13% sodium dodecyl sulfate (SDS)/polyacrylamide gels. Polypeptides were identified using matrix-assisted laser desorption/ionization and electrospray ionization mass spectrometry after in-gel protein digestion. Some of the upregulated polypeptides in malignant cells are of potential importance as markers of tumor proliferation. Twenty such proteins were identified, ten constituting novel identifications and ten sequence verifications of previously gel-matched proteins. The proteins identified span a wide range of functions, but several cases of protein truncation were found. Truncated forms of cytokeratins 6D and 8, and of cathepsin D were identified. Truncated froms of these over-expressed proteins support the presence of proteolytic processing steps in tumor material. The protein processing and the difference between protein and mRNA abundancies in tumors of different malignancy and origin suggest that studies at the protein level are important for an understanding of tumor phenotypes. 相似文献
93.
Kawasaki T Ogawa A Terashima R Saheki T Ban N Sekiguchi H Sakaguchi KE Sakamoto M 《The Journal of organic chemistry》2005,70(8):2957-2966
Hexahydropyrrolo[2,3-b]indoles 6 were synthesized in five steps from indolin-3-one 8 by a general and efficient method, in which elements of molecular diversity were readily added onto the 3a-position of the pyrrolo[2,3-b]indole ring system. Horner-Wadsworth-Emmons reaction of 2-allyloxyindolin-3-ones 7, derived from indolin-3-one 8 and a variety of allylic alcohols, smoothly proceeded with successive Claisen rearrangement to give the corresponding 3-allyl-3-cyanomethylindolin-2-ones 15. Indolin-2-ones 15 were converted into pyrrolo[2,3-b]indoles 6 using partial hydrolysis followed by reductive cyclization with LiAlH(4). Synthesis of N-methylated pyrrolo[2,3-b]indole derivatives 23 and 26 is also described. 相似文献
94.
Tayama O Nakano A Iwahama T Sakaguchi S Ishii Y 《The Journal of organic chemistry》2004,69(16):5494-5496
A facile method for the synthesis of organophosphonates from alkenes and dialkyl phosphites was developed by the use of Mn(II) under air. Thus, the reaction of 1-octene with diethyl phosphite in the presence of Mn(OAc)2 (5 mol %) under air at 90 degrees C led to diethyl octylphosphonate (78%) and diethyl (2-hexyl)decylphosphonate (6%). Internal alkenes such as cis-2-octene gave a regioisomeric mixture of the corresponding hydrophosphorylation products in 84% yields. 相似文献
95.
A novel strategy for production of mono- and dicarboxylic acids by the addition of carboxyalkyl radicals to alkenes and dienes, respectively, was successfully developed through a catalytic process with use of Mn(II)/Co(II)/O(2) system. Thus, a variety of carboxylic acids were prepared by the reaction of alkenes and dienes with acid anhydrides in the presence of a very small amount of Mn(OAc)(2) (0.5 mol %) and Co(OAc)(2) (0.1 mol %) under dilute dioxygen. 相似文献
96.
Ishii Y Takeno M Kawasaki Y Muromachi A Nishiyama Y Sakaguchi S 《The Journal of organic chemistry》1996,61(9):3088-3092
Cp(2)Sm(thf)(2) was found to be an efficient catalyst for the acylation of alcohols and amines with esters under mild conditions. In the present acylation, vinyl and isopropenyl acetates served as good acylating agents. Thus, a variety of alcohols and amines underwent acylation with vinyl and isopropenyl acetates in the presence of Cp(2)Sm(thf)(2) to give the corresponding esters and amides in good to excellent yields. This catalytic acylation of alcohols and amines offers an additional useful method by the use of various esters, instead of acid anhydrides and acid chlorides, as acylating agents under very mild conditions. 相似文献
97.
The electrofluorination of acetamide (CH3CONH2) and formamide (HCONH2) on the anode was studied in a molten KH2F3 at 120°C. Amorphous carbon was used as the anode and Pt rod as the reference electrode. Anodic products were analyzed by both gas chromatography and infrared spectroscopy.In the both CH3CONH2 and HCONH2, the anode effect did not occur in the current density range of 3-11mA2cm2 and anode gas was then composed of N2(+O2), NF3, CF4, C2F6, N2O, CO2(+COF2) and so on. The addition of 1.0w% LIF to the electrolyte was available for prevention from the anode effect.From these results, it is suggested that CH3CONH2 and HCONH2 would react chemically with fluorine radical produced by the discharge of fluoride ion and that the change of the CmFn [(CF)n?I] film on the anode to (CF)n [(CF)n?II] film was prevented specially in the case of HCONH2. The mechanism of electrofluorination of CH3CONH2 in the melt is as folIows; CH3CONH2 CH3COF,·NH2 N2,NF3,CF4,C2F6,CHF3,COF2(CO2),N2O. 相似文献
98.
Carpenter JE Christoffels A Weinbach Y Hide WA 《Journal of computational chemistry》2002,23(7):755-757
The exponential increase in expressed sequence tag (EST) sequence data amplifies the computational cost of clustering sequences such that new algorithms are required to analyze data at a greater rate. We have parallelized d2_cluster on a SGI Origin 2000 multiprocessor and observed a speedup of approximately 100x on 126 processors when processing a 15,876 EST dataset. The parallelized d2_cluster code is obtainable from the SANBI website (http://www.sanbi.ac.za/CODES). 相似文献
99.
Terai T Osakabe K Katai M Sakaguchi K Narama I Matsuura T Katakawa J Tetsumi T 《Chemical & pharmaceutical bulletin》2003,51(3):351-353
Novel 9alpha and 9beta-hydroxy grayanotoxin II derivatives were prepared by photo-sensitized oxygenation of iso-grayanotoxin II and oxidation of grayanotoxin II tetraacetate with selenium dioxide respectively. The lethal dosage of 9alpha and 9beta-hydroxy grayanotoxin II were lower than that of grayanotoxin II. In addition, the lethal dosage of 9beta-hydroxy-dihydro grayanotoxin II was higher than that of dihydro grayanotoxin II. 相似文献
100.
Kenzo Kitayama Masanori Sakaguchi Youhei Takahara Hiroyuki Endo Hirofumi Ueki 《Journal of solid state chemistry》2004,177(6):1933-1938
Phase equilibrium was established in the Y-Fe-O system at 1100°C by varying the oxygen partial pressure from −log(PO2/atm)=15.00 to 0, allowing construction of a phase diagram at 1100°C for the system Y2O3-Fe-Fe2O3. In the system, two ternary compounds, YFeO3 and Y3Fe5O12, were stable and had nonstoichiometric composition, whereas YFe2O4 was not found to be stable. The present result was different from that of previous studies at 1200°C, in which YFe2O4 was stable, along with the above two ternary compounds. Lattice constants of YFeO3 and Y3Fe5O12, prepared in air by a quenching method, were determined and compared with previous values, and showed close agreement. The standard Gibbs energy changes of the reactions in the Fe-O system, Fe+1/2O2=FeO, 3FeO+1/2O2=Fe3O4, and 2/3Fe3O4+1/6O2=Fe2O3, were determined, and the obtained values were compared with the previous values. The standard Gibbs energy changes of the reactions, Fe+1/2Y2O3+3/4O2=YFeO3, and 3YFeO3+2/3Fe3O4+1/6O2=Y3Fe5O12, were calculated from the oxygen partial pressures in equilibrium. 相似文献