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101.
Masaaki Abe Haruo Akashi Kiyoshi Isobe Akihiko Nakanishi Atsushi Yagasaki 《Journal of Cluster Science》1996,7(1):103-107
The methallyl moieties of [{(3-C4H7)2Rh}2(V4O12)]2– couple to yield 2,5-dimethyl-1,5-hexadiene in a selective manner by the action of P(OEt),3, while the reaction of [(
3-C4H7)2 Rh(acac)] with P(OEt)3 produces a mixture of organic compounds. The result shows that the vanadate support has a significant influence on the reactivity of organometallic complexes. 相似文献
102.
YanCAI MingQingCHEN JuanXU PinFangWU AkashiMITSURU XiaoHuaHUAN 《中国化学快报》2004,15(9):1109-1112
Poly (N-vinylacetamide) (PNVA) was synthesized by the free radical polymerization and its samarium (Ⅲ) binary complex was prepared and characterized by means of IR, UV-vis, X-ray photoelectron spectroscopy (XPS) and fluorescence spectra. The fluorescent intensity of samarium (Ⅲ) characteristic emission was increased significantly due to efficient energy transfer from polymeric ligand to Sm (Ⅲ) ion in the complex. 相似文献
103.
Jong‐Ha Choi Takayoshi Suzuki Md. Abdus Subhan Sumio Kaizaki Yu Chul Park 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(7):m409-m412
The crystal structure of the title compound, (C2H10N2)[Cr(C4H9N2O2)2]2Cl4·2H2O, has been determined by single‐crystal X‐ray diffraction studies at 293 and 100 K. The analyses demonstrated that the crystal consists of ethylenediammonium dications (which lie about inversion centres), bis[N‐(2‐aminoethyl)glycinato]chromium(III) monocations, Cl? anions and hydrate water molecules, in a molecular ratio of 1:2:4:2. The complex cation unit has a slightly distorted octahedrally coordinated Cr atom, with two Cr—O and four Cr—N bonds in the ranges 1.951 (1)–1.953 (1) and 2.054 (1)–2.089 (2) Å, respectively, at 293 K. The geometry of the bis[N‐(2‐aminoethyl)glycinato]chromium(III) moiety was found to be trans,cis,cis with respect to the carboxylate O atom and the primary and secondary amine N atoms. The two analyses, at 293 and 100 K, exhibited no remarkable structural differences, although the colour of the crystals did differ, being red at 293 K and orange at 100 K. 相似文献
104.
Yasuaki Mori Sumio Goto Sukeo Onodera Syoji Naito Shoji Takitani Hidetsuru Matsushita 《Fresenius' Journal of Analytical Chemistry》1993,345(1):63-67
Summary A HPLC method using a fluorescence detector is described for the determination of halogenated benz(a)anthracenes (BAX, x=Cl or Br) in water. It consists of the following three procedures; (1) liquid-liquid extraction of BAX with benzene, (2) elimination of interfering compounds from the extracts by one dimensional dual-band thin layer chromatography, and (3) quantitative determination of BAX by HPLC equipped with a fluorescence detector. The recoveries of BAX from water samples through the entire analytical procedure amounted to more than 72%. The calibration curves for BAX were linear, e.g., with a range from 1 to 20 ng ml–1 for 7-chlorobenz(a)anthracene (BACl). The lower detection limit for BACl was 20 pg for an injection volume of 20 l. This method has been applied to BAX in river water spiked with benz(a)anthracene [B(a)A] at 10 ng ml–1 after chlorination. B(a)A, BACl and BABr were found in the levels of 2.01, 0.16 and 0.13 or less ng ml–1, respectively. 相似文献
105.
Yuge R Yudasaka M Miyawaki J Kubo Y Ichihashi T Imai H Nakamura E Isobe H Yorimitsu H Iijima S 《The journal of physical chemistry. B》2005,109(38):17861-17867
We succeeded in large-scale preparation of single-wall carbon nanohorns (SWNH) encapsulating C60 molecules in a liquid phase at room temperature using a "nano-precipitation" method, that is, complete evaporation of the toluene from a C60-SWNH-toluene mixture. The C60 molecules were found to occupy 6-36% of the hollow space inside the SWNH, depending on the initial quantity of C60. We showed that the C60 in C60@SWNHox was quickly released in toluene, and the release rate decreased by adding ethanol to toluene. Numerical analysis of the release profiles indicated that there were fast and slow release processes. We consider that the incorporation quantity and the release rate of C60 were controllable in/from SWNHs because SWNHs have large diameters, 2-5 nm. 相似文献
106.
The 3′,5′-diene derivative of kanamycin B () was obtained from a 4′-ene derivative of kanamycin B () by treatment with trimethyl orthoacetate. Formation of the title compound () from deaminative cyclization with sodium methoxide followed by treatment with trifluoroacetic acid was described. 相似文献
107.
Sunatsuki Y Ohta H Kojima M Ikuta Y Goto Y Matsumoto N Iijima S Akashi H Kaizaki S Dahan F Tuchagues JP 《Inorganic chemistry》2004,43(14):4154-4171
The [Fe(II)(H(3)L)](BF(4))(2).3H(2)O (1) complex was synthesized, where H(3)L (tris[[2-[(imidazole-4-yl)methylidene]amino]ethyl]amine) is a tripodal ligand obtained by condensation of tris(2-aminoethyl)amine and 4-formylimidazole (fim) in a 1:3 molar ratio. Starting from 1, a series of complexes, [Fe(II)(H(1.5)L)](BF(4))(0.5) (2) (=[Fe(II)(H(3)L)][Fe(II)(L)]BF(4)), [Fe(H(1.5)L)]BF(4) (3) (=[Fe(II)(H(3)L)][Fe(III)(L)](BF(4))(2)), [Fe(III)(H(3)L)](BF(4))(3).fim.H(2)O (4), and [Fe(III)(L)].2.5H(2)O (5), has been synthesized and characterized. The single-crystal X-ray structure of each complex has been determined. The Fe(II) compound, 2, and a mixed valence Fe(II)-Fe(III) compound, 3, involve formally hemi-deprotonated ligands, H(1.5)L. The structure of 3 consists of a homochiral two-dimensional assembled sheet, arising from the intermolecular hydrogen bonds between [Fe(II)(H(3)L)](2+) and [Fe(III)(L)](0) (3). All but 5 exhibit spin crossover between low-spin (LS) and high-spin (HS) states. This is a rare case where both Fe(II) and Fe(III) complexes containing the same ligand exhibit spin-crossover behavior. Magnetic susceptibility and M?ssbauer studies showed that 3 has three accessible electronic states: LS Fe(II)-LS Fe(III), HS Fe(II)-LS Fe(III), and HS Fe(II)-HS Fe(III). Compounds 1-3 show the light-induced excited spin-state trapping effect at the Fe(II) sites upon irradiation with green light. The solution magnetic properties, electronic spectra, and electrochemical properties of 1, 4, and 5 were also studied. 相似文献
108.
Photochemistry of α,α-bisulfenylated ketone has been investigated. Irradiation of 2-phenylthiodihydrothiophen-3-one (1) in benzene gave the radical recombination products 9 (63%) and 10 (49%). In a polar solvent, the ionic chemistry became predominant. Brief irradiation of 1 in acetonitrile and methanol gave the cis-fused dihydrothiophene 11 as the major product in 43% and 20% yields, respectively. The stereoselective photocyclization was generally observed for other ketones (2–8) in acetonitrile solution (Table 1). The photo-products were easily dehydrated by treating with boron trifluoride etherate to give the corresponding benzothiophenes in high yields. Simple α-phenylthioketones are photoinert under the same conditions. The mechanism of this novel photocyclization of bisulfenylated ketones is also discussed. 相似文献
109.
Kaizaki Sumio Kita Przemyslaw Wiśniewska Joanna Sakagami Narumi 《Transition Metal Chemistry》1998,23(4):511-515
Three new complex ions, [Cr(NCS)(R-pdtrp)]-, [Cr(R-pdtrp)(NCSHg)]+ and [Cr(edtrp)(NCSHg)]+, that are derivatives of the trans-equatorial isomers of [Cr(R-pdtrp)(H2O)]0 and [Cr(edtrp)(H2O)]0 (edtrp= ethylenediamine-N,N,N-tripropionate, R-pdtrp= R-propane-1,2-diamine-N,N,N-tripropionate) have been obtained and characterized in solution. Rate constants and activation parameters, including, in two cases, volumes of activation, have been determined. Rate retardation for NCS- ligand release has been observed with increasing acidity within the pH 0–2 range. The mechanism of the reactions has been discussed. 相似文献
110.
Grubišic Sonja Gruden-Pavlović Maja Niketić Svetozar R. Sakagami-Yoshida Narumi Kaizaki Sumio 《Transition Metal Chemistry》2003,28(1):37-42
The structure of trans-equatorial [Cr(edtrp)(H2O)] · 3H2O (edtrp3– is the anion of ethylenediamine-N,N,N-tripropionic acid) was determined by single crystal X-ray diffraction. The chromium(III) ion is surrounded octahedrally by the two nitrogen and three oxygen atoms of the quinquedentate edtrp3–, forming a five-membered diamine ring and the three six-membered -propionato chelate rings. The remaining coordination position is occupied by the H2O ligand. The crystal structure conformation is compared to the result of recent molecular mechanics analysis. The ring strain of R and G chelate rings was found to be in agreement with the previously proposed mechanisms for the C—N bond cleavage and recombination. 相似文献