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31.
Mahmoud Sawsan A. Mohamed Fatma E. El-Sadek B. M. Elsawy M. M. Bendary Samar H. 《Journal of Solid State Electrochemistry》2021,25(8):2345-2360
Journal of Solid State Electrochemistry - In this context, the electrical conductivity and surface activity of cobalt sulphide (CoS) as counter electrode CE is improved by incorporating with... 相似文献
32.
Achim Müller Samar K. Das Vladimir P. Fedin Erich Krickemeyer Christian Beugholt Hartmut Bgge Marc Schmidtmann Bjrn Hauptfleisch 《无机化学与普通化学杂志》1999,625(7):1187-1192
The blue mixed-crystal title compound Na15[MoMoO462H14 (H2O)70]0.5[MoMoO457H14 · (H2O)68]0.5 · ca. 400 H2O ≡ Na15[ 1 a ]0.5[ 1 b ]0.5 · ca. 400 H2O 1 , which crystallizes in the triclinic space group P 1 (a = 30.785(2), b = 32.958(2), c = 47.318(3) Å, α = 90.53(1), β = 89.86(1), γ = 96.85(1)°, V = 47665(6) Å3, Z = 2, Dcalc = 2.149 g cm–3), precipitates within one day when an acidic (pH ≈ 1) aqueous solution of sodium molybdate (because of the extremely high solubility of the reaction product used in relatively high concentration) is reduced by sodium dithionite. 1 contains hitherto unknown pure molybdenum-oxide based, nanosized, ring-shaped, crystallographically independent cluster anions of the type {Mo154} 1 a and {Mo152} 1 b , the lacunary-type analogue of 1 a . Using the same reducing agent but in the presence of a reagent with a high affinity to the specific {Mo2}-type building unit (also a leaving group) of 1 a , such as formic acid, the compound Na22[MoMoO442H14(H2O)58] · ca. 250 H2O 2 (space group P 1, a = 24.724(1), b = 35.726(2), c = 44.608(3) Å, α = 93.25(1), β = 93.51(1), γ = 106.72(1)°, V = 37552(4) Å3, Z = 2, Dcalc = 2.401 g cm–3) is obtained in which the giant rings, having four missing {Mo2} units compared to 1 a , are linked to chains. Until now, similar chain-type compounds could only be obtained using a non-well-defined synthetic method. 相似文献
33.
Mirza Nadeem Ahmad Sohail Nadeem Mohsin Javed Shahid Iqbal Sadaf ul Hassan Samar O. Aljazzar Eslam B. Elkaeed Rami Adel Pashameah Eman Alzahrani Abd-ElAziem Farouk Mohammed T. Alotaibi Hisham S. M. Abd-Rabboh 《Molecules (Basel, Switzerland)》2022,27(17)
The synthesis of MMT and poly(o-anisidine) (MMT/POA) clay nanocomposites was carried out by using the chemical oxidative polymerization of POA and MMT clay with POA, respectively. By maintaining the constant concentration of POA, different percentage loads of MMT clay were used to determine the effect of MMT clay on the properties of POA. The interaction between POA and MMT clay was investigated by FTIR spectroscopy, and, to reveal the complete compactness and homogeneous distribution of MMT clay in POA, were assessed by using scanning-electron-microscope (SEM) analysis. The UV–visible spectrum was studied for the optical and absorbance properties of MMT/POA ceramic nanocomposites. Furthermore, the horizontal burning test (HBT) demonstrated that clay nanofillers inhibit POA combustion. 相似文献
34.
Samar O. Aljazzar 《光谱学与光谱分析》2021,41(6):1971-1975
One of the phenolic acids is 4-hydroxybenzoic acid (HBA) which takes the form of a white crystalline solid with a molecular formula of C7H6O3, a melting point of 214.5 ℃ and a molecular weight of 138.12 g·mol-1. It soluble in polar organic solvents like acetone and alcohols, and slightly soluble in chloroform and water. The reactions between the metal ions and the HBA were carried out under specific conditions like (molar reaction was 2∶2 (ligand to metal), reaction temperature was 60 ℃, media was neutral (pH 7), and solvent was H2O ∶MeOH (1∶1). Under these conditions, the HBA was deprotonated to form (HOC6H4CO-2; L-). The ligand L- was coordinated to the metal ions forming the metal complexation. The reaction of 4-hydroxybenzoic acid (HOC6H4CO2H; HL) with the Ni(Ⅱ), Mn(Ⅱ) and Cu(Ⅱ) ions afford metal-complexes with gross formula of [Ni2L2(NO3)2(H2O)4], [Mn2L2(NO3)2(H2O)4] and [Cu2L2(NO3)2(H2O)4], respectively. These complexes were characterized by elemental analysis (CHN), magnetic susceptibility, UV-Vis spectra, infrared (IR), and X-ray powder diffraction (XRD) techniques. The complexes of HBA are insoluble in common solvents and hence molar conductance could not be measured, but this very insolubility indicates that the complexes are neutral. Data has demonstrated that the ligand (L-) was coordinated to the metal ion by bidentate bridging carboxylate group (COO-), with an octahedral geometry. Thus, HBA is expected to act as bidentate uninegative ions and the coordination number of the metal ions is six. XRD results showed that the complexes possess uniform and organized microstructures in the nanometer range with a main diameter in the range of 11~28 nm. 相似文献
35.
Mohammed Samar M. Moustafa Ahmed H. El-Sayed Hassan A. Ayman Aya Mohamed Abdussattar S. A. 《Russian Journal of General Chemistry》2022,91(1):S84-S88
Russian Journal of General Chemistry - Functionalization of α-aminopyridine to a new series of pyridine and fused pyridine derivatives has been achieved via its reaction with a variety of... 相似文献
36.
El-Sayed Hassan A. Moustafa Ahmed H. Farargy Ahmed F. El Mohammed Samar M. Saudy Esraa Gad Emad M. 《Russian Journal of General Chemistry》2022,92(4):709-717
Russian Journal of General Chemistry - The present study is devoted to functionalization of ethyl 2-{[3-cyano-6-(4-cyanophenyl)-4-(2,4-dichlorophenyl)pyridin-2-yl]oxy}acetate (1) by triazole-,... 相似文献
37.
Wanas AS Matsunami K Otsuka H Desoukey SY Fouad MA Kamel MS 《Chemical & pharmaceutical bulletin》2010,58(12):1596-1601
From the EtOAc and 1-BuOH fractions, three new ursane-type and four new lupane-type triterpenes, along with nine known glycosides and glycosyl esters of lupane-type were isolated from the leaves of Schefflera actinophylla. All the isolated compounds were obtained for the first time from this plant. The structures of the new triterpenes were determined through a combination of spectroscopic and chemical analyses. 相似文献
38.
Pankaj Gupta Vijay K. Sethi Subhash C. Taneja Bhahwal A. Shah Samar S. Andotra Surrinder Koul Swapandeep S. Chimni Ghulam N. Qazi 《Helvetica chimica acta》2007,90(1):196-204
A series of odoriferous cyclic ethers, including nerol oxide ( 1 ), Florol® ( 2 ), Florol methyl ether ( 3 ), and Pityol® methyl ether ( 4b ), were prepared by a versatile synthetic protocol based on co‐halogenation with 1,3‐dibromo‐5,5‐dimethylhydantoin (= 1,3‐dibromo‐5,5‐dimethylimidazolidine‐2,4‐dione; DDH) as the key step. The methodology provides a facile access to important perfumery molecules from abundantly available monoterpene alcohols. 相似文献
39.
The extract of Casimiroa edulis was investigated for antihypertensive activity. The ethanol and total alkaloids (in chloroform) extracts were found to have
antihypertensive properties at doses of 500 and 200 mg/kg, respectively. Four quinolinone alkaloids were isolated and identified
as: 2-(2′-hydroxy-4′-methoxyphenyl)-5,8-dimethoxy-3-propyl-1H-quinolin-4-one (1), 5,8-dimethoxy-2-(3′-methoxyphenyl)-3-propyl-1H-quinolin-4-one (2), 5,8-dimethoxy-2-(3′,4′-dimethoxyphenyl)-3-propyl-1H-quinolin-4-one (3), and 5,6-dimethoxy-2-(2′,5′,6′-trimethoxyphenyl)-1H-quinolin-4-one (4). Interestingly, compounds 1, 2, and 3 were found to be new alkaloids. The four isolated alkaloids showed antihypertensive activity at doses of 50, 100, 200, and
300 mg/kg, respectively.
Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 473–476, September–October, 2007. 相似文献
40.
Two Anderson-type heteropolyanion-supported copper phenanthroline complexes, [Al(OH)6Mo6O18[Cu(phen)(H2O)2]2]1+ (1c) and [Al(OH)6Mo6O18[Cu(phen)(H2O)Cl]2]1- (1a) complement their charges in one of the title compounds [Al(OH)6Mo6O18[Cu(phen)(H2O)2]2][Al(OH)6Mo6O18[Cu(phen)(H2O)Cl]2].5H2O [1c][1a].5 H2O 1. Similar charge complementarity exists in the chromium analogue, [Cr(OH)6Mo6O18[Cu(phen)(H2O)2]2][Cr(OH)6Mo6O18[Cu(phen)(H2O)Cl]2].5 H2O [2c][2a].5 H2O 2. The chloride coordination to copper centers of 1a and 2a makes the charge difference. In both compounds, the geometries around copper centers are distorted square pyramidal and those around aluminum/chromium centers are distorted octahedral. Three lattice waters, from the formation of intermolecular O-H.....O hydrogen bonds, have been shown to self-assemble into an "acyclic water trimer" in the crystals of both 1 and 2. The title compounds have been synthesized in a simple one pot aqueous wet-synthesis consisting of aluminum/chromium chloride, sodium molybdate, copper nitrate, phenanthroline, and hydrochloric acid, and characterized by elemental analyses, EDAX, IR, diffuse reflectance, EPR, TGA, and single-crystal X-ray diffraction. Both compounds crystallize in the triclinic space group P. Crystal data for 1: a = 10.7618(6), b = 15.0238(8), c = 15.6648(8) angstroms, alpha = 65.4570(10), beta = 83.4420(10), gamma = 71.3230(10), V = 2182.1(2) angstroms3. Crystal data for 2: a = 10.8867(5), b = 15.2504(7), c = 15.7022(7) angstroms, alpha = 64.9850(10), beta = 83.0430(10), gamma = 71.1570(10), V = 2235.47(18) angstroms3. In the electronic reflectance spectra, compounds 1 and 2 exhibit a broad d-d band at approximately 700 nm, which is a considerable shift with respect to the value of 650-660 nm for a square-pyramidal [Cu(phen)2L] complex, indicating the coordination of [M(OH)6Mo6O18]3- POM anions (as a ligand) to the monophenanthroline copper complexes to form POM-supported copper complexes 1c, 1a, 2c, and 2a. The ESR spectrum of compound 1 shows a typical axial signal for a Cu2+ (d9) system, and that of compound 2, containing both chromium(III) and copper(II) ions, may reveal a zero-field-splitting of the central Cr3+ ion of the Anderson anion, [Cr(OH)6Mo6O18]3-, with an intense peak for the Cu2+ ion. 相似文献