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21.
The extraction of Cu(II) with 1-phenyl-3-methyl-4-acyl-5-pyrazolone (HA), in different organic solvents has been studied. The extraction mechanism of Cu(II) and the composition of the extracted species has been determined. Cu(II) was extracted as CuA2, or in the presence of TOPO, as CuA2TOPO. The extraction constants do not change regularly with increasing the length of acyl chain in the 1-phenyl-3-methyl-4-acyl-5-pyrazolone derivatives. The effect of the temperature on the extraction of Cu(II) has also been investigated. 相似文献
22.
In the presence of a catalytic amount of tetrakis(triphenylphosphine)platinum(0), allenes undergo carbonylative thiolation with carbon monoxide and thiols to provide the corresponding α,β- and β,γ-unsaturated thioesters in good yields. In contrast, the use of rhodium(I) catalysts such as RhH(CO)(PPh3)3 in place of Pt(PPh3)4 leads to copolymerization of allenes and carbon monoxide without incorporation of thio groups. 相似文献
23.
Takuya Miyazaki Yoshiaki Shoji Fumitaka Ishiwari Takashi Kajitani Takanori Fukushima 《Chemical science》2020,11(32):8388
As a new element for electric-field driven molecular memory, we developed a hexaarylbenzene derivative in which three difluorophenyl groups and three aryl groups as a dipolar rotor and a rotation suppressor, respectively, are alternately positioned on the central benzene core. This molecule has two rotational isomeric forms, both of which preserve their conformational states at room temperature but exhibit interconversion at high temperatures. Amorphous thin films fabricated from the hexaarylbenzene show a reversible change in surface potential by application of electric fields.A hexaarylbenzene derivative with an alternating circular array of dipolar rotors and rotation suppressors holds promise as a new element for electric-field driven molecular memory. 相似文献
24.
Takayoshi Tsuzuki Natsumi Sakaguchi Dr. Takashi Kudoh Satoshi Takano Masato Uehara Dr. Takashi Murayama Prof. Dr. Takashi Sakurai Dr. Minako Hashii Prof. Dr. Haruhiro Higashida Karin Weber Prof. Dr. Andreas H. Guse Dr. Tomoshi Kameda Dr. Takatsugu Hirokawa Dr. Yasuhiro Kumaki Prof. Dr. Barry V. L. Potter Dr. Hayato Fukuda Dr. Mitsuhiro Arisawa Prof. Dr. Satoshi Shuto 《Angewandte Chemie (International ed. in English)》2013,52(26):6633-6637
25.
The cobalt dithiolene complex with the sulfonylamide-substituted Cp ligand [(C5H4-NHTs)Co{S2C2(COOMe)2}] (1, Ts = p-SO2C6H4Me) reacted with TsOH · H2O to give [(C5H4-NH2)Co{S2C2(COOMe)(H)}] (2), [(C5H4-NHTs)Co(S2C2H2)] (3) and [(C5H4-NHTs)Co{S2C2(COOMe)(H)}] (4). Complex 1 was dissolved in a basic aqueous solution, and the anion reacted with Me2SO4 to form the N-methylated product [{C5H4-N(Me)Ts}Co{S2C2(COOMe)2}] (5); the carboxylic acid complex [{C5H4-N(Me)Ts}Co{S2C2(COOMe)(COOH)}] (6) formed by a base hydrolysis. The X-ray crystal structures of complexes 4-6 and the methylsulfonylamide-substituted Cp complex [(C5H4-NHMs)Co{S2C2(COOMe)2}] (7, Ms = SO2Me) were determined. In the crystal structures of complexes 4 and 7, intermolecular hydrogen bondings of NH?O (ca. 2.1 Å) and NH?S (ca. 3.1 Å) were observed. Complex 6 showed the OH?O intermolecular hydrogen bonding (ca. 1.6 Å) of COOH moiety between two molecules, and these two molecules were assembling each other. Complexes 5 and 6 showed an intramolecular π-π interaction between the aromatic cobaltadithiolene and benzene rings, and complex 5 also has intermolecular π-π interactions between two benzene rings, and between two cobaltadithiolene rings. 相似文献
26.
Itsuo Mori Takako Matsuo Yoshikazu Fujita Minako Toyoda Kenichi Ichitani Noriko Inoue 《Fresenius' Journal of Analytical Chemistry》1994,348(5-6):346-349
Summary A spectrofluorophotometric determination of thallium(III) is proposed. It is based on the enhancement of the fluorescence reaction of 3,4,5,6-tetrachlorofluorescein (TCF) with Pyrogallol Red (PR) by thallium(III) in the presence of Swanol (AM 301, lauryldimethyl aminoacetic acid betain) as an amphoteric surfactant. The method was found to be suitable for the determination of thallium(III) down to 4.0 g in 10.0 ml by measuring the difference in the relative fluorescence intensities of a TCF/PR/thallium(III) solution and a TCF/PR solution. The recovery test in artificial urine was satisfactory (96±2%). 相似文献
27.
A facile synthesis of novel 1,2-diazepino[3,4-b]quinoxalines by a 1,3-dipolar cycloaddition reaction
Ho Sik Kim Yoshihisa Kurasawa Chiemi Yoshii Minako Masuyama Atsushi Takada Yoshihisa Okamoto 《Journal of heterocyclic chemistry》1990,27(3):819-822
The 1,3-dipolar cycloaddition reaction of the quinoxaline 4-oxides 4a,b with 2-chloroacrylonitrile gave the 2,3-dihydro-1H-1,2-diazepino[3,4-b]quinoxalines 5a,b , respectively, which were converted into the 2,3,4,6-tetrahydro-1H-1,2-diazepino[3,4-b]quinoxalines 7a,b and 8a,b , respectively. 相似文献
28.
Itsuo Mori Yoshikazu Fujita Minako Toyoda Sachiko Kubo 《Fresenius' Journal of Analytical Chemistry》1992,342(1-2):80-82
Summary The alternative and simultaneous spectrophotometric determination of niobium and tantalum was examined by using the colour development between o-hydroxyhydroquinonephthalein (Qnph) and niobium or tantalum in the presence of hexadecyltrimethylammonium chloride (HTAC) in strong acidic media. Beer's law was obeyed up to 10.0 g of niobium and up to 18.0 g of tantalum in a final volume of 10.0 ml. The apparent molar absorption coefficients for niobium and tantalum were 2.18×105 and 2.09×105 l mol–1 cm–1 with Sandell's sensitivities of 0.00042 g/cm2 niobium at 520 nm and 0.00085 g/cm2 tantalum at 510 nm, respectively. The alternative assay of niobium and tantalum was possible by using two methods: Method A — masking method with oxalic acid, Method B — acid adjusting-method using 50% sulfuric acid. These methods were 2–6-times more sensitive than other methods.Application of xanthene derivatives in analytical chemistry. Part XC. Part LXXXIX see ref [1] 相似文献
29.
The Effects of Serum on Cellular Uptake and Phototoxicity of Mono-L-Aspartyl Chlorin e6 (NPe6) In Vitro 总被引:1,自引:0,他引:1
Llyar Sheyhedin Katsuo Aizawa Minako Araake Hideo Kumasaka Tetsuya Okunaka Harubumi Kato 《Photochemistry and photobiology》1998,68(1):110-114
Abstract— Previous reports showed that the photosensitizer mono- l -aspartyl chlorin e6 (NPe6) binds to serum proteins. However, the influence of this binding on the cellular uptake and photodynamic therapy (PDT) phototoxicity of NPe6 is still undefined. In this paper, we studied how serum in medium affected the P388 cellular uptake and PDT phototoxicity of NPe6 in vitro. This was assessed by (1) detection of the red shift (654 nm Q band peak of absorption) induced by protein binding NPe6; (2) detection of intracellular concentration of NPe6 by HPLC and (3) measurements of the cell survival ratio after PDT by MTT assay. The 654 nm Q band peak of NPe6 shifted to 665 nm after binding of NPe6 and serum proteins. The protein-bound NPe6 cannot be uptaken by cells, thus there was no PDT phototoxicity. Nevertheless, phototoxicity recovered when the concentration of NPe6 excessed the serum protein binding ability or there was free serum protein in the medium. These data suggested that the cellular uptake of NPe6 is inhibited by serum components in the medium, and that only free NPe6 is accumulated by P388 cells even during relatively long incubations. The cytotoxicity of PDT mainly depends on the free NPe6 level in the medium. 相似文献
30.
Ikuko Tsukamoto Madoka Saito Minako Yamane Kenji Kawata Yuji Kitamura Youji Kitamura Masaki Mifune Yutaka Saito Jun Haginaka 《Analytical sciences》2006,22(7):1035-1038
The effect of the central metal of columns packed with silica gels binding Ni(2+)- and Cu(2+)-phthalocyanine derivatives (Ni-and Cu-PCS(D)s) on the retention behavior of poly-aromatic-hydrocarbons (PAHs) thereof in a polar eluent was examined. The retention factors of PAHs on the Ni- and Cu-PCS(D)s in 80% methanol showed a good linear correlation. The Cu-PCS(D) column exhibited the pi-pi interactions for PAHs, while the Ni-PCS(D) column exhibited the pi-d interactions for PAHs in addition to the pi-pi interaction for PAHs. Further, an investigation of the retention behavior of anthracene derivatives having different substituents revealed that the Ni- and Cu-PCS(D) columns could recognize the differences of substituents only in a polar eluent. 相似文献