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61.
Oana Carp E. Segal Maria Brezeanu Luminita Patron R. Barjega N. Stanica 《Journal of Thermal Analysis and Calorimetry》1996,47(3):857-869
The authors analyse the possibility of obtaining manganese-zinc ferrite through the transformations of polynuclear coordination compounds (pcc), either in the solid state or in a reaction medium. Polynuclear coordination compound precursors with the general molecular formula: [Fe(II)xFe(III)y(Mn0.5Zn0.5)(C2O4)2(OH)y+2(H2O)2] with 0.2相似文献
62.
Claudia Maria Simonescu V. S. Teodorescu Oana Carp Luminita Patron Camelia Capatina 《Journal of Thermal Analysis and Calorimetry》2007,88(1):71-76
Thermal behaviour of CuS (covellite) obtained from the Cu(CH3COO)2·H2O and Na2S2O3·5H2O
system, working at different molar ratio (1:6 and 1:4) in presence/absence
of NH4VO3, was studied. It was
established that the presence of vanadium in the system induces a densification
of CuS nodules, but do not change the hexagonal CuS structure. It has an important
influence in thermal behaviour of copper sulfide CuS obtained also. The morphological
characteristics of CuS play an important role in the thermal stability and
the stoichiometry of the thermal decompositions.
Also, the possibility
to obtain copper sulfides with greater cooper content was investigated. 相似文献
63.
Using the properties of the generating function of the Hermite polynomials, we have calculated the matrix elements for the Gaussian-type potential VG(x)=A exp{−B(x−C)2} and for the Morse-type potential VM(x)=De[1−exp(−ax)]2 in the basis of the non-degenerate harmonic oscillator wavefunctions. The final forms of these matrix elements are very simple to use and hence suitable for the numerical resolution of the Schrödinger equation for multiple-well potentials or anharmonic oscillators. 相似文献
64.
P. Budrugeac Alice Luminita Petre E. Segal 《Journal of Thermal Analysis and Calorimetry》1996,47(1):123-134
The validity of isoconversional methods used to evaluate the activation energy is discussed. The authors have shown that the Flynn-Wall-Ozawa and Friedman methods give results that agree with each other only if the activation energy does not change with the degree of conversion. A criterion for the reaction mechanism as expressed by the differential conversion function is suggested too. 相似文献
65.
Toma L Lescouëzec R Vaissermann J Delgado FS Ruiz-Pérez C Carrasco R Cano J Lloret F Julve M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(23):6130-6145
The preparation, X-ray crystallography and magnetic investigation of the compounds PPh4[Cr(bipy)(CN)4].2 CH3CN.H2O (1) (mononuclear), [[Cr(bipy)(CN)4]2Mn-(H2O)4].4H2O (2) (trinuclear), [[Cr(bipy)(CN)4]2Mn(H2O)2] (3) (chain) and [[Cr(bipy)(CN)4]2Mn(H2O)].H2O.CH3CN (4) (double chain) [bipy=2,2'-bipyridine; PPh4 (+)=tetraphenylphosphonium] are described herein. The [Cr(bipy)(CN)4]- unit act either as a monodentate (2) or bis-monodentate (3) ligand toward the manganese atom through one (2) or two (3) of its four cyanide groups. The manganese atom is six-coordinate with two (2) or four (3) cyanide nitrogens and four (2) or two (3) water molecules building a distorted octahedral environment. In 4, two chains of 3 are pillared through interchain Mn-N-C-Cr links which replace one of the two trans-coordinated water molecules at the manganese atom to afford a double chain structure where bis- and tris-monodenate coordination modes of [Cr(bipy)(CN)4]- coexist. The magnetic properties of 1-4 were investigated in the temperature range 1.9-300 K. A Curie law behaviour for a magnetically isolated spin quartet is observed for 1. A significant antiferromagnetic interaction between CrIII and MnII through the single cyanide bridge [J=-6.2 cm(-1), the Hamiltonian being defined as H=-J(SCr1.SMn+SCr2.SMn] occurs in 2 leading to a low-lying spin doublet which is fully populated at T <5 K. A metamagnetic behaviour is observed for 3 and 4 [the values of the critical field Hc being ca. 3000 (3) and 1500 Oe (4)] which is associated to the occurrence of weak interchain antiferromagnetic interactions between ferrimagnetic Cr2III MnII chains. The analysis of the exchange pathways in 2-4 through DFT type calculations together with the magnetic bevaviour simulation using the quantum Monte Carlo methodology provided a good understanding of their magnetic properties. 相似文献
66.
Coralia Cotoraci Alina Ciceu Alciona Sasu Eftimie Miutescu Anca Hermenean 《Molecules (Basel, Switzerland)》2021,26(9)
The use of biologically active compounds has become a realistic option for the treatment of malignant tumors due to their cost-effectiveness and safety. In this review, we aimed to highlight the main natural biocompounds that target leukemic cells, assessed by in vitro and in vivo experiments or clinical studies, in order to explore their therapeutic potential in the treatment of leukemia: acute myeloid leukemia (AML), chronic myeloid leukemia (CML), acute lymphocytic leukemia (ALL), and chronic lymphocytic leukemia (CLL). It provides a basis for researchers and hematologists in improving basic and clinical research on the development of new alternative therapies in the fight against leukemia, a harmful hematological cancer and the leading cause of death among patients. 相似文献
67.
Musuc Adina Magdalena Patrinoiu Greta Budrugeac Petru Cucos Andrei Dascalu Radu Calderon-Moreno Jose Carp Oana 《Journal of Thermal Analysis and Calorimetry》2022,147(22):12805-12814
Journal of Thermal Analysis and Calorimetry - The combustion behavior of fructose-derived hydrochar was investigated using a kinetic evaluation protocol that brings about novel elements related to... 相似文献
68.
Adina Magdalena Musuc Domnina Razus Dumitru Oancea 《Journal of Thermal Analysis and Calorimetry》2009,98(3):779-784
The thermal decomposition of new N-methoxy-polynitroanilines was studied using the differential scanning calorimetry (DSC) method. The characteristic melting
parameters were measured and the activation parameters of the most probable kinetic models of thermal decomposition were determined
using a multivariate non-linear regression method. All investigated compounds followed an autocatalytic decomposition mechanism.
Depending on the number and position of substituents on the aromatic ring the thermal decomposition occurs in one, two or
three steps. 相似文献
69.
The biochemistry of the para-sulfonato-calix[n]arenes has shown rapid development during the past ten years, the highly diverse biomedical applications of these molecules now include anti-viral, anti-thrombotic activities, enzyme blocking and protein complexation. The future is even more promising as para-sulfonato-calix[n]arenes have, now, been shown to have potential in the diagnosis of prion-based diseases. Their innocuous nature, as far as is known at present, may open up their future use in medications. 相似文献
70.
The aim of this paper is to obtain high efficient and inexpensive spectral selective solar absorbers, for solar thermal flat plat collectors using a simple technique – spray pyrolysis deposition (SPD). To achieve maximum solar absorptance and minimum thermal emittance, the following parameters are optimized: the precursor solution concentration and composition, substrate temperature and annealing treatment. The structural and morphological properties of the films were investigated by X-ray diffraction, atomic force microscopy and contact angle measurements. The thermal emittance and solar absorptance of as-deposited films were correlated with the chemical composition, crystalline structure and morphology. The results prove that coatings with excellent spectral selective properties (normal solar absorptance of 0.92 and a normal thermal emittance of 0.03) can be obtained by SPD. 相似文献