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31.
Effect of electronic polarization on charge-transport parameters in molecular organic semiconductors
Valeev EF Coropceanu V da Silva Filho DA Salman S Brédas JL 《Journal of the American Chemical Society》2006,128(30):9882-9886
Theoretical investigations of charge transport in organic materials are generally based on the "energy splitting in dimer" method and routinely assume that the transport parameters (site energies and transfer integrals) determined from monomer and dimer calculations can be reliably used to describe extended systems. Here, we demonstrate that this transferability can fail even in molecular crystals with weak van der Waals intermolecular interactions, due to the substantial (but often ignored) impact of polarization effects, particularly on the site energies. We show that the neglect of electronic polarization leads to qualitatively incorrect values and trends for the transfer integrals computed with the energy splitting method, even in simple prototypes such as ethylene or pentacene dimers. The polarization effect in these systems is largely electrostatic in nature and can change dramatically upon transition from a dimer to an extended system. For example, the difference in site energy for a prototypical "face-to-edge" one-dimensional stack of pentacene molecules is calculated to be 30% greater than that in the "face-to-edge" dimer, whereas the site energy difference in the pentacene crystal is vanishingly small. Importantly, when computed directly in the framework of localized monomer orbitals, the transfer integral values for dimer and extended systems are very similar. 相似文献
32.
In this paper we have proved a main theorem concerning the | $\bar N$ , p n; δ |k summability methods, which generalizes a result of Bor and Özarslan [3]. 相似文献
33.
Betül en Serap Alp Gülsiye
ztürk Muhittin Aygün Orhan Büyükgüngr 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(4):o223-o224
Molecules of the title compound, C24H19NO6S, adopt the Z configuration and have a distorted tetrahedral geometry around the S atom. The oxazolone, 2‐phenyl and methoxyphenyl rings are approximately coplanar. The C atom between the methoxyphenyl and oxazolone rings displays a distorted trigonal bonding geometry. Pairs of molecules are linked into dimers through weak C—H⋯O hydrogen bonds. 相似文献
34.
Omer L. Gebizlioglu Serap Yörübulut 《Methodology and Computing in Applied Probability》2016,18(4):1043-1064
Pareto distributions are very flexible probability models with various forms and kinds. In this paper, a new bivariate Pseudo-Pareto distribution and its properties are presented and discussed. Main variables, order statistics and concomitants of this distribution are studied and their importance for risk and reliability analysis is explained. Joint and marginal distributions, complementing cumulative distributions and hazard functions of the variables are derived. Numerical illustrations, graphical displays and interpretations for the obtained distributions and derived functions are provided. An implementation example on defaultable bonds is performed. 相似文献
35.
36.
Gulsah Bor Ezgi Man Ozge Ugurlu Ayse Elcin Ceylan Simge Balaban Ceren Durmus Z. Pinar Gumus Serap Evran Suna Timur 《Electroanalysis》2020,32(9):1922-1929
Pesticide use in agriculture is one of the threats to water safety. Therefore, detection of pesticide residues is crucial for human health. Compared to conventional chromatographic methods, aptasensors are promising tools for fast, cheap and sensitive detection of environmental contaminants. To the best of our knowledge, such an aptasensor has not been reported for imidacloprid (Imi) which is one of the most widely used pesticides. In order to meet this demand, we initially selected two novel aptamers designated as ‘Apta‐1’ and ‘Apta‐2’ by graphene oxide‐SELEX (GO‐SELEX) method. Then, these aptamers were used to fabricate the gold electrode‐based aptasensor platforms and characterized by using electrochemical methods such as cyclic voltammetry, and electrochemical impedance spectroscopy as well as X‐Ray photoelectron spectroscopy. It was found that the limit of detection value of Apta‐1 based sensor for the Imi was found better than Apta‐2 based system, although linear ranges were similar. Based on that finding, Apta‐1 based system was further tested against possible interference molecules. The proposed platform was successfully used for detection of very low concentrations of Imi in the range of ng/mL. Thus, it eliminates the need for sample pre‐treatment and enables a practical analysis in real wastewater samples. 相似文献
37.
The cobalt and nickel complexes of some heterocyclic substituted azomethins have been synthesized. Metal/azomethine ratio of these complexes has been studied.
Teil der Dissertation,. Kaban, Univ. Istanbul 1975. 相似文献
Teil der Dissertation,. Kaban, Univ. Istanbul 1975. 相似文献
38.
P?ivi M?ki-Arvela Serap Sahin Narendra Kumar Jyri-Pekka Mikkola Kari Er?nen Tapio Salmi Dmitry Yu. Murzin 《Reaction Kinetics and Catalysis Letters》2008,94(2):281-288
Liquid phase tert-butylation of m-cresol was carried out using 12-tungstosilicic acid supported on neutral alumina by varying different parameters. The reaction
has also been carried out by using calcined samples under optimized conditions. The present catalyst shows an excellent activity
of 93.2%, conversion of 100% selectivity for the o-isomer, an important industrial product. 相似文献
39.
5,10,15,20-tetrakis(phenoxy acetic acid) porphyrin (PAAP) was covalently linked to Merrifield chloromethylated resin. Characterization
of PAAP and the modified polymeric matrix were performed by 1H NMR, FTIR and elemental analysis. The sorbent was used for the separation and enrichment of the d-electron metals (Mn(II), Co(II), Ni(II), Cu(II) and Zn(II)) at pH 6–8 and of the f-electron metals U(VI) and Th(IV) at pH 4–5. The metals ions were preconcentrated with a concentration factor range of 115–215
and then determined by flame atomic absorption spectrometry or visible spectrophotometry using Arsenazo(III). The retained
metals were eluted with 2.0 mol L−1 HNO3 in the case of the d-electron metals and 0.1/0.25 mol L−1 HCl in the case of the f-electron metals. The procedure was validated by analyzing the NIST standard reference material 2709 (San Joaquin Soil).
Correspondence: Melek Merdivan, Chemistry Department, Faculty of Arts and Sciences, Dokuz Eylul University, 35160 Buca, Izmir,
Turkey 相似文献
40.
Hasan Sezer Sezgin Fazilet Zumrut Biber Muftuler Cigdem Ichedef Ayfer Yurt Kilcar Serap Teksoz Perihan Unak Coskun Harmansah 《Journal of Radioanalytical and Nuclear Chemistry》2017,313(2):291-297
Penetrant technique is a sensitive non-destructive testing (NDT) method for detecting and locating the presence of cracks in sample surface. Today, NDT is used in a wide range of industries including aerospace, biotechnology, defence, marine, oil–gas and energy plants. This work focuses on potential use of radiolabeled ZnS coated CdTe quantum dots (QDots) as a penetrant for liquid penetrant testing. The synthesized QDots as a precursor were tested for surface defects detection in welded joints. The experimental results show the highest activities were found in defects on the sample surface. These finding are consistent with the sample NDT inspection test report. 相似文献