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131.
The potentiometric response characteristics of zinc ion selective PVC-based membrane electrode employing 1,12,14-triaza-5,8-dioxo-3(4),9(10)-dibenzoyl-1,12,14-triene as an inophore was investigated. The proposed electrode exhibits a Nernstian behavior with a slope of 29.2 ± 0.4 mV per decade with a working concentration range of 1.3 × 10?7–1.0 × 10?1 mol L?1 and a detection limit of 1.0 × 10?8 mol L?1. The membrane having the composition as TDODBCPT:O-NPOE:PVC:OA; 7:57:30:6 wt.% exhibits the best results. It has a fast response time of 7 s and can be used for at least 100 days without any considerable divergence in potential. The proposed electrode show good discrimination of Zn2+ ion from diverse ions. The potential response remains constant over a pH range of 3.5–9.2. The electrode found well work under laboratory conditions. The proposed sensor directly used for determination of zinc ions in human hair sample, wastewater and an indicator electrode with EDTA titration. 相似文献
132.
Yughandhar Sreedhar Neelam Rekha Dasari P. Reddy Prasad M. Sankar Nayak 《Journal of Saudi Chemical Society》2010,14(2):149-155
A novel analytical reagent 4-(2-hydroxy phenyl ethaminodiol), benzene-1,3-diol(4-2-HPEDB-1,3,D) was synthesized for the determination of molybdenum(VI). The present paper reveals the detailed study of electroanalytical behaviour for [Mo-(4-2-HPEDB-1,3,D)] complex under optimized conditions. The peak obtained for [Mo-(4-2-HPEDB-1,3,D)] prevent the interference of foreign ions which shows the sensitivity of the proposed method. The linearity was maintained at the concentration range of 0.5–200 μg/mL at pH 4.5 with correlation factor 0.9997. The present method was successfully applied for the analysis of molybdenum(VI) in biological fluids and plant material. The results obtained from the proposed method show good agreement with reference method. 相似文献
133.
Prashant Singh Pradeep Kumar Anju Katyal Rashmi Kalra Sujata K. Dass Satya Prakash Ramesh Chandra 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2010,75(3):983-991
In the present work, we report the synthesis and characterization of novel charge-transfer complexes of thiazolidine-2,4-dione (TZD) with sigma acceptor (iodine) and pi acceptors (chloranil, dichlorodicyanoquinone, picric acid and duraquinone). We also evaluated their thermal and electrochemical properties and we conclude that these complexes are frequency dependent. Charge-transfer complex between thiazolidine-2,4-dione and iodine give best conductivity. In conclusion, complex with sigma acceptors are more conducting than with pi acceptors. 相似文献
134.
K. Chandra Babu Raman Vysabhattar K.S.V. Srinivas Satish Nigam G. Madhusudhan K. Mukkanti 《Tetrahedron: Asymmetry》2010,21(21-22):2619-2624
We report an asymmetric synthesis of (4S,5S)-2-oxo-4-phenyloxazolidine-5-carboxylic acid via stereoselective addition of phenylmagnesium bromide (PhMgBr) to an N-sulfinimine derived from (R)-glyceraldehyde acetonide. (S)- and (R)-Glyceraldehyde acetonides, important chiral synthons in synthetic organic chemistry, are prepared from the corresponding epichlorohydrin using an identical synthetic methodology. 相似文献
135.
Dulal Chandra Kabiraz Tapan Kumar Biswas M. Entazul Huque 《Monatshefte für Chemie / Chemical Monthly》2010,39(11):1063-1068
Abstract
The apparent molar volumes (φ v) of KCl, KNO3, MgCl2, and Mg(NO3)2 have been determined in water and in aqueous sodium dodecylsulfate solutions from density measurements at 303.15, 308.15, 313.15, 318.15, and 323.15 K. The limiting apparent molar volumes (jv0 \varphi_{v}^{0} ) and experimental slopes (S v) were derived from the Masson equation. The partial molar volume transfer (\Updelta [`(V)]\texttr ) (\Updelta {\bar{V}}_{\text{tr}} ) of the electrolytes were obtained from limiting apparent molar volume data from water to aqueous sodium dodecylsulfate solutions and have been interpreted in terms of ion–ion, hydrophilic–hydrophilic, and hydrophobic–hydrophobic interactions on the basis of a co-sphere overlap model. It is shown that the transfer volumes (\Updelta [`(V)]\texttr ) (\Updelta {\bar{V}}_{\text{tr}} ) are positive and increase with increasing sodium dodecylsulfate concentration for all electrolytes. The structure making or breaking capacities of the electrolytes have been inferred from the sign of [∂2 φ v0/∂T 2]p, i.e., the second derivative of the limiting apparent molar volume with respect to temperature at constant pressure. In water, KCl and KNO3 exhibit structure breaking and MgCl2 and Mg(NO3)2 exhibit structure making behavior. All the studied electrolytes were found to act as structure makers in aqueous sodium dodecylsulfate solutions. 相似文献136.
Carlos Rodríguez-Abreu Margarita Sanchez-Domínguez Bojan Šarac Marija Bešter Rogač Rekha Goswami Shrestha Lok Kumar Shrestha Dharmesh Varade Goutam Ghosh Vinod K. Aswal 《Colloid and polymer science》2010,288(8):923-935
Mixtures of a hydrophobic triblock copolymer (L121, PEO5PPO68PEO5) and a hydrophobic anionic surfactant (AOT, Sodium bis(2-ethylhexyl)sulfosuccinate), each alone forming turbid vesicular
solutions in water, aggregate to produce a thermodynamically stable, transparent and isotropic solution. Mixed AOT/L121 aggregates
could be confirmed by fluorescence, surface tension, differential scanning calorimetry (DSC) and isothermal titration calorimetry
(ITC). In an isotropic region, where mixed aggregates are formed, there is a synergistic interaction between monomers of AOT
and L121 in the mixture. In addition, Small Angle Neutron Scattering (SANS) experiments provided evidence that mixed aggregates
have the shape of either spheres (with a certain polydispersity) or very short ellipsoids (axial ratio below 2), confirming
a transition from giant multilamellar vesicles to small aggregates upon mixing the two hydrophobic amphiphiles. Upon dilution,
the morphology changes to disk-like. From an examination of the results of all the methods the peculiar behavior of the mixed
AOT/L121 system is explained. 相似文献
137.
Maria A. Mendoza DeEtta K. Mills Hemant Lata Suman Chandra Mahmoud A. ElSohly Jose R. Almirall 《Analytical and bioanalytical chemistry》2009,393(2):719-726
Cannabis sativa is the most frequently used of all illicit drugs in the USA. Cannabis has been used throughout history for its stems in the
production of hemp fiber, seed for oil and food, and buds and leaves as a psychoactive drug. Short tandem repeats (STRs) were
chosen as molecular markers owing to their distinct advantages over other genetic methods. STRs are codominant, can be standardized
such that reproducibility between laboratories can be easily achieved, have a high discrimination power, and can be multiplexed.
In this study, six STR markers previously described for C. sativa were multiplexed into one reaction. The multiplex reaction was able to individualize 98 cannabis samples (14 hemp and 84 marijuana, authenticated as originating from 33 of the 50 states of the USA) and detect
29 alleles averaging 4.8 alleles per loci. The data did not relate the samples from the same state to each other. This is
the first study to report a single-reaction sixplex and apply it to the analysis of almost 100 cannabis samples of known geographic
origin.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
138.
B. Muktha Debajyoti Mahanta Giridhar Madras 《Journal of solid state chemistry》2007,180(10):2986-2989
An heterogeneous conducting polymer composite, poly(3-hexylthiophene)/TiO2 (P3HT/TiO2), was synthesized. The photocatalytic activity of P3HT alone and the composite was investigated for the first time by degrading a common dye under UV exposure. It was shown that the photocatalytic activity of the nanocomposites was higher compared to either the polymer or TiO2 alone. A simple mechanism was proposed to explain this observed synergetic effect. 相似文献
139.
Nand Kishor Gour Bhupesh Kumar Mishra Iftikar Hussain Ramesh Chandra Deka 《Structural chemistry》2016,27(5):1491-1499
Kinetics and thermochemistry of the H-atom abstraction reaction of CH3OCH2CH2Cl with OH radical have been carried out using dual level of methods. Initially, geometry optimization and frequency calculations are performed at M06-2X/6-31+G(d, p) level of theory, and energetic calculations are further refined using CCSD(T)/6-311++G(d, p) level of theory in order to characterized all stationary points on potential energy surface (PES). The result shows that H-atom abstraction from –OCH2 site of CH3OCH2CH2Cl is dominant path. The rate constants are calculated using canonical transition state theory at 298 K, which are found to be in good agreement with the experimental data. We have presented the standard enthalpies of formation for CH3OCH2CH2Cl and the radicals generated during the H-atom abstraction using group-balanced isodesmic reactions scheme. The atmospheric lifetime of title molecule is also calculated. 相似文献
140.
Manna SC Zangrando E Ribas J Ray Chaudhuri N 《Dalton transactions (Cambridge, England : 2003)》2007,(14):1383-1391
Polymeric networks, {[Co(dpyo)(ox)]}(n) (1), {[Co(dpyo)(fum)(H(2)O)(2)]}(n) (1) and {[Co(dpyo)(tp)(H(2)O)(2)] x [Co(H(2)O)(6)] x (tp) x (H(2)O)}(n) (3) [ox = oxalate dianion, fum = fumarate dianion, tp = terephthalate dianion and dpyo = 4,4'-dipyridyl N,N'-dioxide] have been synthesized and characterized by single crystal X-ray diffraction analyses. The structural determination reveals 1 and 2 are covalent bonded 2D networks of 4,4 topology and of these, complex 2 undergoes a H-bonding scheme resulting in a 3D supramolecular architecture. Complex 3 is a 1D coordination polymer built up by almost collinear hexacoordinated Co(ii), doubly bridged by a tp carboxylate group and a dpyo oxygen, which in combination with lattice [Co(H(2)O)(6)](2+), tp and water molecules shows an unprecedented 3D supramolecular network through H-bonding. In the polymer the dpyo shows novel mu-4,4 bridging mode towards the cobalt ion. Low temperature magnetic interaction reveals antiferromagnetic coupling in all of the complexes. 相似文献