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11.
Efficient routes to hitherto unknown 1d-2,5-di-azido-di-deoxy-allo-inositol, 1d-2,5-di-amino-di-deoxy-allo-inositol, 1l-1-azido-1-deoxy-chiro-inositol and 1l-1-amino-1-deoxy-chiro-inositol were developed by using cheaply available myo-inositol as the starting material. Preliminary investigations on the enzyme inhibitory properties were done. The methodology reported is amenable to gram scale synthesis and thus can find application in natural product synthesis. 相似文献
12.
Shigendo?Enomoto Ken-ichi?Kumagai Taro?Tamura Miki?Hasegawa Kyoko?Nakada Toshihiko?Hoshi Michio?KobayashiEmail author 《Monatshefte für Chemie / Chemical Monthly》2004,135(5):471-481
Summary. Fluoranthene (FA) forms a 1:1 van der Waals complex with benzene in cyclohexane. The 1H NMR spectrum of this complex shows that the FA moiety in the complex state has five kinds of hydrogen atoms and that the 1H NMR peaks assigned to the protons attached to the naphthalene skeleton are largely shifted to higher magnetic field on complex formation with benzene. These observations indicate that the complex takes the structure of CS symmetry, in which the benzene molecule mainly interacts with the electronic system localized on the naphthalene moiety of FA. The present ab initio calculations reproduce well the 1H NMR spectral shifts mentioned above and the experimentally predicted CS structure of the complex. According to the PPP calculations for the electronic absorption spectral changes on the complex formation, the FA-benzene complex is considered to take a sandwich type structure. 相似文献
13.
Ikuta A Mizuta N Kitahata S Murata T Usui T Koizumi K Tanimoto T 《Chemical & pharmaceutical bulletin》2004,52(1):51-56
Six novel branched beta-cyclodextrins (betaCDs) having beta-D-galactose residues on the non-reducing terminal of the sugar side chains, namely 6(1),6(4)-di-O-(beta-D-galactosyl)-betaCD (10), 6-O-(beta-D-galactosyl)-betaCD (11), 6(1),6(4)-di-O-(beta-lactosyl)-betaCD (14), 6-O-(beta-lactosyl)-betaCD (15), 6(1),6(4)-di-O-(4'-O-beta-D-galactosyl-beta-lactosyl)-betaCD (18), and 6-O-(4'-O-beta-D-galactosyl-beta-lactosyl)-betaCD (19), were chemically synthesized using the trichloroacetimidate method. The reaction products were separated by HPLC on an amino column into dibranched and monobranched betaCDs. Their structures were confirmed by mass spectrometry (MS) and two-dimensional (2D) NMR spectroscopic analysis. To study the length of the sugar side chains attached to the CD ring, which leads to differences in the functions of the branched CDs, interactions of these compounds with peanut (Arachis hypogaea) agglutinin (PNA) were investigated using an optical biosensor and an inhibition assay based on hemagglutination. The results showed that all branched betaCDs interacted with PNA, and the binding affinity was 18>14>10 and 19>15>11 when the derivatives were compared on the basis of side chain length. 相似文献
14.
Prof. Dr. Akira Watanabe Dr. Hisako Tamai Mrs. Kyoko Hayashi 《Colloid and polymer science》1977,255(8):773-781
Summary The adsorption of ionic dyes, the builder effect, and the interaction between ionic dyes and surface active agents were investigated by using the electrocapillarity at oil/water interfaces. The oil phase was the solution of tetra-butylammonium chloride, sodium cetylsulphate, cetylpyridinium chloride or stearylamine in methylisobutylketone, and the water phase contained various dyes in addition to the inorganic electrolyte. The interfacial tension decreased over the anodic (or cathodic) polarization range, when anionic (or cationic) dyes were added to the water phase, thus indicating the dye adsorption at the interface. The interfacial excess of dye ions was found to increase linearly with the cubic roots of dye concentration and of ionic strength of the water phase. The counterion binding took place at the oil/water interface between anionic (or cationic) dyes and positive (or negative) head groups of surface active agent ions adsorbed at the interface. It was found that the equilibrium constants of binding between anionic dyes and cationic surface active agents at the oil/water interface were of the same order of magnitude as, and a little larger than, those obtained at the water bulk phase.
With 12 figures and 2 tables 相似文献
Zusammenfassung An Öl-Wasser-Grenzflächen wurde die Adsorption ionischer Farbstoffe, die Füllerwirkung und die Wechselwirkung zwischen ionischen Farbstoffen und grenzflächenaktiven Verbindungen mit Hilfe der Elektrokapillarität untersucht. Die Ölphase bestand aus einer Lösung von Tetrabutylammoniumchlorid, Natriumcetylsulfat und Cetylpyridiniumchlorid oder Stearylamin in Methylisobutylketon. Die wässerige Phase enthielt verschiedene Farbstoffe und anorganische Elektrolyte. Die Grenzflächenspannung wurde durch anodische (bzw. kathodische) Polarisation erniedrigt, wenn anionischer (bzw. kationischer) Farbstoff zur Wasserphase gegeben wurde. Dies zeigt an, daß Farbstoff an der Grenzfläche adsorbiert wird. Die Grenzflächenkonzentration des Farbstoffions nimmt linear mit der Kubikwurzel der Farbstoffkonzentration und mit der Ionenstärke zu. Als Gegenionen für die anionischen (bzw. kationischen) Farbstoffe an der Grenzfläche wirken die positiven (bzw. negativen) Endgruppen der Tenside, die ebenfalls in der Grenzschicht adsorbiert sind. Die Gleichgewichtskonstanten für die Wechselwirkung zwischen den ionischen Farbstoffen und den grenzflächenaktiven Verbindungen sind an der Öl-Wasser-Grenzfläche von der gleichen Größenordnung bzw. geringfügig größer als in der wässerigen Volumenphase.
With 12 figures and 2 tables 相似文献
15.
Kawahara K Sekiguchi A Kiyoki E Ueda T Shimamura K Kurosaki Y Miyaoka S Okabe H Miyajima M Kimura J 《Chemical & pharmaceutical bulletin》2003,51(3):336-338
Newly formulated cationic liposomes (TRX-liposomes) with four different mean diameters were injected into twelve male rats via the lateral tail vein in order to evaluate the effect of liposomal size on pharmacokinetic parameters. TRX-liposomes disappeared from the blood according to the one-compartment model and demonstrated maximum and minimum half-lives of ca. 14 h (mean diameter of 114.3 nm) and ca. 5 h (mean diameter of 285.9 nm), respectively. This prolonged half-life tended to decrease at the boundary of 114.3 nm mean diameter. The optimal size (114.3 nm) for prolonged circulation of TRX-liposomes was consistent with that of pegylated liposomes such as Doxil((R)), however, the half-life was different among these liposomes. The electric charge of the TRX-liposomal surface is assumed to be responsible for this difference. The results of the present study will be very useful in the design of long-circulating cationic liposomes. 相似文献
16.
Takehiko Nishio Kyoko Iseki Norihito Araki Takenori Miyazaki 《Helvetica chimica acta》2005,88(1):35-41
The radical reactions of N‐(2‐halogenoalkanoyl)‐substituted anilines (anilides) of type 1 have been investigated under various conditions. Treatment of compounds 1a – 1o with Bu3SnH in the presence of (2,2′‐azobis(isobutyronitrile) (AIBN) afforded a mixture of the indolones (oxindoles) 2a – 2o and the reduction products 5a – 5o (Table 1). In contrast, the N‐unsubstituted anilides 1p – 1s, 1u , and 1v gave the corresponding reduction products exclusively (Table 1). Similar results were obtained by treatment of 1 with Ni powder (Table 2) or wth Et3B (Table 3). Anilides with longer N‐(phenylalkyl) chains such as 6 and 7 were inert towards radical cyclization, with the exception of N‐benzyl‐2‐bromo‐N,2‐dimethylpropanamide ( 6b ), which, upon treatment with Ni powder in i‐PrOH, afforded the cyclized product 9b in low yield (Table 4). Upon irradiation, the extended anilides 6, 7, 10 , and 11 yielded the corresponding dehydrobromination products exclusively (Table 5). 相似文献
17.
The asymmetric hydroformylation of 2‐ and 3‐vinylfurans ( 2a and 2b , resp.) was investigated by using [Rh{(R,S)‐binaphos}] complexes as catalysts ((R,S)‐binaphos = (11bS)‐4‐{[1R)‐2′‐phosphino[1,1′‐binaphthalen]‐2‐yl]oxy}dinaphtho[2,1‐d:1′,2′‐f][1,3,2]dioxaphosphepin; 1 ). Hydroformylation of 2 gave isoaldehydes 3 in high regio‐ and enantioselectivities (Scheme 2 and Table). Reduction of the aldehydes 3 with NaBH4 successfully afforded the corresponding alcohols 5 without loss of enantiomeric purity (Scheme 3). 相似文献
18.
Wenjie Tao Xiaoming Wang Shingo Ito Kyoko Nozaki 《Journal of polymer science. Part A, Polymer chemistry》2019,57(3):474-477
Herein, we report the synthesis of palladium complexes bearing an N‐heterocyclic carbene (NHC)‐sulfonamide bidentate ligand and their application in ethylene oligomerization and ethylene/polar monomer cooligomerization. These catalysts could smoothly catalyze ethylene oligomerization and ethylene/methyl acrylate cooligomerization albeit the performance was lower compared to that of a NHC–phenoxide catalyst. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 474–477 相似文献
19.
Atsutoshi Yamada Yuki Watanabe Kyoko Noda Sumitaka Itoh Koji Ishihara Masahiko Inamo Refat Moustafa Hassan Hideo D. Takagi 《Journal of solution chemistry》2014,43(9-10):1479-1486
The reduction reaction of the Cu(II)–pitn complex (pitn = 1,3-di(pyridine-2-carboxaldimino)propane) by decamethylferrocene [Fe(Cp*)2] was examined in acetonitrile. The observed pseudo-first-order rate constants exhibited saturation kinetics with increasing excess amount of [Fe(Cp*)2]. Detailed analyses revealed that the reaction is controlled by a structural change prior to the electron transfer step, rather than a conventional bimolecular electron transfer process preceded by ion pair (encounter complex) formation. The rate constant for the structural change was estimated to be 275 ± 13 s?1 at 298 K (?H* = 33.3 ± 1.0 kJ·mol?1, ?S* = 86 ± 5 J·mol?1·K?1), which is the fastest among gated reactions involving CuN4 complexes. It was confirmed by EPR measurement and Conflex calculations that the dihedral angle between the two N–N planes is significantly large (40°) in solution whereas it is merely 17.14° in the crystal. 相似文献
20.
Yohei Saito Atsushi Mizokami Kouji Izumi Renato Naito Masuo Goto Kyoko Nakagawa-Goto 《Molecules (Basel, Switzerland)》2021,26(9)
α-Trifluoromethyl chalcones were prepared and evaluated for their antiproliferative activities against androgen-independent prostate cancer cell lines as well as five additional types of human tumor cell lines. The most potent chalcone 5 showed superior antitumor activity in vivo with both oral and intraperitoneal administration at 3 mg/kg. Cell-based mechanism of action studies demonstrated that 5 induced cell accumulation at sub-G1 and G2/M phases without interfering with microtubule polymerization. Furthermore, several cancer cell growth-related proteins were identified by using chalcone 5 as a bait for the affinity purification of binding proteins. 相似文献