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991.
Mao-Peng Lin Tomiki Ikeda Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》1992,30(12):2569-2576
Vinylether was used as a cationically polymerizable moiety and incorporated into sidechain of polymers as copolymers of vinyloxyethyl methacrylate (VEM) and styrene (St). Photoirradiation of the copolymers containing a small amount of benzyl(4-hydroxyphenyl) methylsulfonium salt (BSS) resulted in a high crosslinking density as evidenced by a low degree of swelling, which is ascribed to the high reactivity of the vinyloxy moieties. The sensitivity of this photoreaction is significantly high because of a large kinetic chain length of the cationic polymerization of vinylethers, while copolymers of glycidyl methacrylate and St showed crosslinking to much less extent when irradiated under the same condition. The ability of other sulfonium salts, (4-hydroxyphenyl) methyl(4-nitrobenzyl) sulfonium salt and (4-hydroxyphenyl) methyl(1-naphthylmethyl)sulfonium salt, to induce photocrosslinking was also examined. © 1992 John Wiley & Sons, Inc. 相似文献
992.
Morikawa MA Yoshihara M Endo T Kimizuka N 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(5):1574-1578
alpha-Helical peptide microcapsules were prepared by the emulsion-templated self-assembly of amphiphilic poly(gamma-benzyl L-glutamate)s (PBLG) 1. By mixing solutions of 1 in dichloromethane (in the form of a sodium salt) with water, oil-in-water emulsions were obtained. Spontaneous stripping of the dichloromethane phase caused a decrease in the diameter of the microdroplets and finally stable microcapsules formed. The microcapsules contain an inner aqueous phase as observed by confocal laser scanning microscopy (CLSM). Binding of hydrophobic pyrene molecules to the polypeptide shell was also demonstrated. The present polypeptide microcapsules are stable even after drying in air and they would serve as supramolecular vehicles for both hydrophobic and water-soluble molecules. 相似文献
993.
Takeshi Furuya Tetsuya Ishikawa Toshitaka Funazukuri Yoshihiro Takebayashi Satoshi Yoda Katsuto Otake Tohru Saito 《Fluid Phase Equilibria》2007
The reduction of sulfur content in gasoline and diesel fuel is a great environmental concern to reduce the motor vehicle emissions. Oxidative desulfurization using acetonitrile biphasic system has received much attention in recent years. The oxidative desulfurization can be oxidized the unreactive sulfur contents in the hydrodesulfurization and removed effectively. For the oxidative desulfurization process design and development, liquid–liquid equilibria (LLE) for acetonitrile biphasic systems are needed as fundamental information. In our previous work, LLE for acetonitrile + n-octane and + n-decane systems have been reported. In this work, therefore, LLE for acetonitrile + n-hexadecane system was measured. Furthermore, NRTL equation was applied to correlate the LLE for these three acetonitrile + n-alkane systems. 相似文献
994.
(+)-Benzoylselenopederic acid (1), a left half of (+)-pederin (3), was synthesized stereoselectively based on the Zn(BH4)2 reduction and total synthesis of (+)-pederin (3) was accomplished from 1 and the previously synthesized 2. 相似文献
995.
Takeshi Miyamoto 《Journal of organometallic chemistry》1977,134(3):335-362
The preparation, IR and NMR spectra of 123 platinum hydrides of the general formula, trans-PtHX(PBz3)2 or trans-PtHL(PBz3)2BPh4 (X = a uninegative anionic ligand, L = a neutral donor molecule, Bz = benzyl), are described. Neutral platinum hydrides have been synthesized by the reduction of trans-PtCl2-(PBz3)2 with NaBH4, by the Michaelis—Arbuzov rearrangement, or by metathesis. Cationic hydridoplatinum(II) complexes are obtained from the reaction of trans-PtHX(PBz3)2 (X = Cl or NO3) with a donor molecule (L) in the presence of NaBPh4, or by coordinating a donor molecule through use of PtH(PBz3)2BPh4 · CH2Cl2. The observed trends in ν(PtH), τ(H), 1J(PtH) and 1J(PtP) in a series of the hydridobenzylphosphineplatinum(II) complexes are discussed in terms of “trans- or cis-influences”, defined as the ability of a ligand to weaken the bond trans or cis to itself. The data support the view that a donor atom trans to the hydridic ligand is important in determining the strength of the PtH bond in this series. Some remarks on the distinctive characteristics of some complexes, e.g., dissociation of coordinated cycloalkanone from platinum(II) or stereochemical non-rigidity of the sym-dimethylurea ligand, are included. Tricyclohexylphosphine analogs also have been prepared for comparison. 相似文献
996.
Yuushou Nakayama Kenji Sogo Hajime Yasuda Takeshi Shiono 《Journal of polymer science. Part A, Polymer chemistry》2005,43(15):3368-3375
Reactions of CrCl3(thf)3 with bis(imino)pyridines gave a series of {bis(imino)pyridine}chromium(III) trichloride complexes, {2,6‐(RN?CMe)2C5H3N}CrCl3 [R = C6HPr2‐2,6 ( 1 ), C6H3Et2‐2,6 ( 2 ), C6H3Me2‐2,6 ( 3 ), C6H2Me3‐2,4,6 ( 4 ), C6H3Me2‐3,5 ( 5 ), C6H5 ( 6 ), cyclohexyl ( 7 ), 2‐methyl‐1‐naphthyl ( 8 ), C6H3F2‐2,6 ( 9 ), C6H3Br2‐2,6 ( 10 ), C6F5 ( 11 )]. Pseudo‐octahedral geometries of 6 , 10 , and 11 were revealed by X‐ray crystallography. The complexes having bulky substituents such as 1 – 4 showed high activity for ethylene polymerization in combination with modified methylaluminoxane (MMAO) to give linear polyethylenes. In sharp contrast, the pentafluorophenyl complex 11 /modified methylaluminoxane system was found to be moderately active for ethylene homopolymerization to give moderately branched polyethylene with only ethyl branches. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3368–3375, 2005 相似文献
997.
A Mo(0) complex containing a new tetraphosphine ligand [Mo(P4)(dppe)] (1; P4 = meso-o-C6H4(PPhCH2CH2PPh2)2, dppe = Ph2PCH2CH2PPh2) reacted with CO2 (1 atm) at 60 °C in benzene to give a Mo(0) carbonyl complex fac-[Mo(CO)(η3-P4O)(dppe)] (2), where the O abstraction from CO2 by one terminal P atom in P4 takes place to give the dangling P(O)Ph2 moiety together with the coordinated CO. On the other hand, reaction of 1 with TolNCS (Tol = m-MeC6H4) in benzene at 60 °C resulted in the incorporation of three TolNCS molecules to the Mo center, forming a Mo(0) isocyanide-isothiocyanate complex trans,mer-[Mo(TolNC)2(η2-TolNCS)(η3-P4S)] (4), where the S abstraction occurs from two TolNCS molecules by P4 and dppe to give the η3-P4S ligand and free dppeS, respectively, together with two coordinated TolNC molecules. The remaining site of the Mo center is occupied by the third TolNCS ligating at the CS bond in an η2-manner. The X-ray analysis has been undertaken to determine the detailed structures for 2 and 4. 相似文献
998.
Masahiko Takahashi Min Zheng Takeshi Oshida Kiyosi Narahara 《Journal of heterocyclic chemistry》1994,31(1):205-207
1,1-Dichloro-3-phenylsulfonyl-2-propanone was treated with arenediazonium chlorides to give 1-arylhydrazono-3,3-dichloro-1-phenylsulfonyl-2-propanones, which were cyclized to 1-aryl-5-chloro-3-(phenylsulfonyl)pyrazol-4-ols on treatmemt with base. 相似文献
999.
Kamata J Okada T Kotake Y Niijima J Nakamura K Uenaka T Yamaguchi A Tsukahara K Nagasu T Koyanagi N Kitoh K Yoshimatsu K Yoshino H Sugumi H 《Chemical & pharmaceutical bulletin》2004,52(9):1071-1081
As part of a series of studies to discover new topoisomerase II inhibitors, novel pyrimidoacridones, pyrimidophenoxadines, and pyrimidocarbazoles were synthesized, and in vitro and in vivo antitumor activities and DNA-protein and/or DNA-topoisomerase II cross-linking activity as an indicator of topoisomerase II-DNA cleavable complex formation were evaluated. The pyrimidocarbazoles possessed high in vitro and in vivo potencies. Compound 26 (ER-37326), 8-acetyl-2-[2-(dimethylamino)ethyl]-1H-pyrimido[5,6,1-jk]carbazole-1,3(2H)-dione, showed in vitro growth inhibitory activity with respective IC(50) values of 0.049 microM and 0.35 microM against mouse leukemia P388 and human oral cancer KB. In vivo, this compound inhibited the tumor growth of mouse sarcoma M5076 implanted into mice with T/C values of 42% and 13% at 3.13 and 6.25 mg/kg/d respectively without significantly affecting the body weight. In addition, compound 26 (ER-37326) increased the formation of DNA-topoisomerase II cross-linking in P388 cells. 相似文献
1000.
Enrico Traversa Maria Luisa Di Vona Patrizia Nunziante Silvia Licoccia Takeshi Sasaki Naoto Koshizaki 《Journal of Sol-Gel Science and Technology》2000,19(1-3):733-736
Ag-TiO2 thin films were prepared with a sol-gel route, using titanium isopropoxide and silver nitrate as precursors, at 0.03 and 0.06 Ag/Ti nominal atomic ratios. After drying at 80°C, the films were fired at 300°C and 500°C for 30 min. The films were analysed by X-ray diffraction (XRD) with glancing angle, and X-ray photoelectron spectroscopy (XPS), with depth profiling of the concentration. XPS analysis showed the presence of C and N as impurities in the nanocomposite films. Their concentration decreased with increasing the firing temperature. Chemical state analysis showed that Ag was present in metallic state, except for the very outer layer where it was present as Ag+. For the films prepared with a Ag/Ti concentration of 0.06, depth profiling measurements of the film fired at 300°C showed a strong Ag enrichment at the outer surface, while composition remained almost constant within the rest of the film, at 0.019. For the films heated to 500°C, two layers were found, where the Ag/Ti ratios were 0.015 near the surface and 0.026 near the substrate. 相似文献