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1.
This paper presents an algorithm and the supporting theory for solving a class of nonlinear multiple criteria optimization problems using Zionts—Wallenius type of interaction. The Zionts—Wallenius method, as extended in this paper, can be used for solving multiple criteria problems with concave objective and (implicit) value functions and convex feasible regions. Modifications of the method to handle nonconvex feasible regions and general nonlinear objective functions are also discussed.This research was supported, in part, by a Faculty Research Development Award and by a Council of 100 Research Grant from Arizona State University (Roy), and by a grant from Y. Jahnsson Foundation, Finland (Wallenius). The research was performed while the second author was a Visiting Professor at Arizona State University. 相似文献
2.
Raj Gandhi Kamales Kar S. Uma Sankar Abhijit Bandyopadhyay Rahul Basu Pijushpani Bhattacharjee Biswajoy Brahmachari Debrupa Chakraborti M. Chaudhury J. Chaudhury Sandhya Choubey E. J. Chun Atri Desmukhya Anindya Datta Gautam Dutta Sukanta Dutta Anjan Giri Sourendu Gupta Srubabati Goswami Namit Mahajan H. S. Mani A. Mukherjee Biswarup Mukhopadhyaya S. N. Nayak M. Randhawa Subhendu Rakshit Asim K. Ray Amitava Raychaudhuri D. P. Roy Probir Roy Suryadeep Roy Shiv Sethi G. Sigl Arunansu Sil N. Nimai Singh Mark Vagins Urjit Yagnik 《Pramana》2003,60(2):405-409
This is the report of neutrino and astroparticle physics working group at WHEPP-7. Discussions and work on CP violation in
long baseline neutrino experiments, ultra high energy neutrinos, supernova neutrinos and water Cerenkov detectors are discussed. 相似文献
3.
Heribert Wiedemeier Asim K. Chaudhuri 《Monatshefte für Chemie / Chemical Monthly》1972,103(1):326-332
Zusammenfassung Durch Röntgenstrahlenbeugung mit Hilfe einer 190 mm Unicam-Hochtemperaturkamera wurde die thermische Ausdehnung von MnSe und MnSe2 von Zimmertemperatur bis 710° bzw. 522° C untersucht. Der thermische Ausdehnungskoeffizient wurde aus den Meßdaten nach der Methode der kleinsten Fehlerquadrate erhalten und beträgt für MnSe: =24,5·10–6°C–1 (94–450° C) und =14,3·10–6°C–1 (450–710° C). Die Ausdehnung von MnSe2 verläuft bis zum Bereich, in dem Zersetzung eintritt, linear. Die Methode der kleinsten Fehlerquadrate ergibt den Wert =20,0·10–6°C–1 (73–522° C).
Mit 2 Abbildungen
Herrn Prof.H. Nowotny gewidmet. 相似文献
High temperature X-ray studies of the thermal expansion ofMnSe andMnSe 2
The thermal expansion of MnSe and MnSe2 has been studied above room temperature up to 710° and 522° C, resp., by X-ray diffraction techniques using a 190 mm Unicam high temperature camera. The thermal expansion coefficients, , obtained from a linear least-squares analysis of the data are for MnSe: =24.5·10–6°C–1 (94–450° C) and =14.3·10–6°C–1 (450–710° C). The expansion of MnSe2 is linear up to the temperature range of decomposition. A least-squares analysis yields a value for of 20.0·10–6°C–1 (73–522° C).
Mit 2 Abbildungen
Herrn Prof.H. Nowotny gewidmet. 相似文献
4.
The standard potentialss
E
o of M/M+ (M=Li, Na, K, Rb, and Cs) electrodes in aqueous urea solutions containing 12, 20, 30 and 37% by weight of urea have been determined at 25°C from emf measurements on the cell M(Hg)/MCl (m), solvent/AgCl–Ag, from the activities of metals in amalgams by use of a similar type of cell in water, and from the values ofs
E
o of the Ag/AgCl electrode determined earlier. The standard free energies of transfer of MCl, G
t
o
(MCl), from water to the mixed solvents, computed by use of these values and those for the Ag–AgCl electrode, rise sharply from Li+ to Na+ but fall from Na+ to K+ and rather sharply from K+ to Cs+ with a maximum at Na+ in all the solvent compositions. This has been attributed to the superimposition of soft-soft interactions on the electrostatic interactions between the ions and the negative charge centers of the possible hydrogen-bonded solvent complexes in the mixed solvents. Comparison of G
t
o
(i) values for individual ions, obtained by a simultaneous extrapolation procedure, with those in aqueous mixtures of methanol,t-butanol, and dimethyl sulfoxide leads to the conclusion that the solvation of these ions in all these solvents is chiefly dictated by the acid-base type of ion-solvent interactions. 相似文献
5.
Summary In acid (HClO4) medium CeIV is reduced to CeIII by 8-hydroxyquinoline (1) and its derivatives, the 5-sulphonate (2) and 7-iodo-5-sulphonate (3), through precursor complex formation. The rates of precursor complex formation have been studied by stopped-flow spectrophotometry for both (1) and (2). Formation of the precursor complex occurs in two concurrent paths involving Ce
aq
4+
and [Ce(OH)]
aq
3+
reacting by Ia and Id processes respectively. The reaction with (3) is, however, too fast for the stopped-flow method. The rates for subsequent intramolecular electron transfer processes in the precursor complexes are sufficiently slow for all the three species(1)–(3) for evaluation by conventional spectrophotometry. For the electron transfer process the rate varies in the sequence:(2)>(1)(3) due to electron-withdrawing character of the substituent SO
3
–
and electron-releasing character of I. 相似文献
6.
Ashis Kumar Pondit Asim Kumar Das Soma Gangopadhyay Debabrata Banerjea 《Transition Metal Chemistry》1988,13(6):437-439
Summary Acid catalysed dissociation of the copper(II) and nickel(II) complexes (ML2+ of the quadridentate macrocyclic ligand 1, 5, 9, 13-tetraaza-2, 4, 4, 10, 12, 12-hexamethyl-cyclohexadecane-1, 9-diene (L) has been studied spectrophotometrically. Both complexes dissociate quite slowly with the observed pseudo-first order rate constants (kobs) showing acid dependence; for the nickel(II) complex (kobs)=kO+kH[H+], the ko path is however absent with the copper(II) complex. At 60°C (I=0.1M) the kH values areca 10–4 M–1 s–1 for both complexes; k
H
Cu
/k
H
Ni
=ca. 3.9, comparable to some other square-planar complexes of these metal ions. The rate difference is primarily due to H values [copper(II) complex, 29.4±0.5 kJ mol–1; nickel(II) complex, 35.6±1.5 kJ mol–1] with highly negative S values [for copper(II), –215.5 ±6.1 JK–1 mol–1 and for nickel(II), –208.1 ±5.6 JK–1 mol–1] which are much higher than the entropy of solvation of Ni2+ (ca. –160 JK–1 mol–1) and Cu2+ (ca. –99 JK–1 mol–1) ions; significant solvation of the released metal ions and the ligand is indicated. 相似文献
7.
Summary In aqueous solution [Cu(bigH)2]2+ (bigH=biguanide) reacts with 2,2-bipyridyl (bipy) and 1,10-phenanthroline (phen) through intermediate formation of ternary complexes [Cu(bigH)(L)]2+ and [Cu(bipy)(phen)]2+ and binary complexes [CuL2]2+ (L=bipy, phen). The rates of the different steps have been followed in borax buffer (pH 8.0±0.1) by stopped-flow spectrophotometry. For each step kobs=k0+kL[L] and the kL path appears to be associative. H and S values for the kL path conform to an isokinetic trend. 相似文献
8.
Gülhan Turan-Zitouni Ahmet Özdemir Zafer Asim Kaplancikli Pierre Chevallet Yagmur Tunali 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2717-2724
The increasing clinical importance of drug-resistant fungal and bacterial pathogens has lent additional urgency to microbiological research and new antimicrobial compound development. For this purpose, new pyrazoline derivatives were synthesized and evaluated for antimicrobial activity. Some 1-[(N, N-disubstitutedthiocarbamoylthio)acetyl]-3,5-diaryl-2-pyrazolines derivatives were synthesized by reacting 1-(chloroacetyl)-3,5-diaryl-2-pyrazolines with appropriate potassium salts of secondary amine dithiocarbamic acids. The chemical structures of the compounds were elucidated by IR, 1 H-NMR, and FAB+-MS spectral data. Their antimicrobial activities against Staphylococcus aureus (B-767), Escherichia coli (B-3704), Pseudomonas aeruginosa (ATCC 27853), Proteus vulgaris (NRLL B-123), and Candida albicans (NRRL-27077) were investigated. The results showed that some of the compounds have notable activity against S. aureus and C. albicans. 相似文献
9.
Ambar Kumar Choudhury Asim Kumar Ray Nirmolendu Roy 《Journal of carbohydrate chemistry》2013,32(8):1153-1163
Abstract Starting from L-fucose, D-glucose and lactose, methyl O-[2,3-di-O-benzoyl-4, 6-O-(4-methoxybenzylidene)-β-D-glucopyranosyl]-(1→4)-2,3-di-O-benzoyl-α-L-fucopyranoside and methyl O-(2,3,4,6-tetra-O-benzyl-β-D-galactopyranosyl)-(1→4)-O-(2,3,6-tri-O-benzyl-α-D-glucopyranosyl)-(1→4)-O-(methyl 2,3-di-O-benzoyl-β-D-glucopyranosyluronate)-(1→4)-2,3-di-O-benzoyl-α-L-fucopyranoside were synthesized. Removal of protecting groups gave the tetrasaccharide repeating unit of the antigen from Klebsiella type-16 in the form of its methyl ester methyl glycoside. 相似文献
10.
Astam K. Patra Arghya Dutta Prof. Dr. Asim Bhaumik 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(37):12388-12395
Mesoporous nanoparticles composed of γ‐Al2O3 cores and α‐Fe2O3 shells were synthesized in aqueous medium. The surface charge of γ‐Al2O3 helps to form the core–shell nanocrystals. The core–shell structure and formation mechanism have been investigated by wide‐angle XRD, energy‐dispersive X‐ray spectroscopy, and elemental mapping by ultrahigh‐resolution (UHR) TEM and X‐ray photoelectron spectroscopy. The N2 adsorption–desorption isotherm of this core–shell materials, which is of type IV, is characteristic of a mesoporous material having a BET surface area of 385 m2 g?1 and an average pore size of about 3.2 nm. The SEM images revealed that the mesoporosity in this core–shell material is due to self‐aggregation of tiny spherical nanocrystals with sizes of about 15–20 nm. Diffuse‐reflectance UV/Vis spectra, elemental mapping by UHRTEM, and wide‐angle XRD patterns indicate that the materials are composed of aluminum oxide cores and iron oxide shells. These Al2O3@Fe2O3 core–shell nanoparticles act as a heterogeneous Fenton nanocatalyst in the presence of hydrogen peroxide, and show high catalytic efficiency for the one‐pot conversion of cyclohexanone to adipic acid in water. The heterogeneous nature of the catalyst was confirmed by a hot filtration test and analysis of the reaction mixture by atomic absorption spectroscopy. The kinetics of the reaction was monitored by gas chromatography and 1H NMR spectroscopy. The new core–shell catalyst remained in a separate solid phase, which could easily be removed from the reaction mixture by simple filtration and the catalyst reused efficiently. 相似文献