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排序方式: 共有178条查询结果,搜索用时 31 毫秒
61.
62.
In this study, 3-(4-{3-[3-(dimethylamino)phenoxy]propoxy}phenyl)propan-1-ol, 3-(4-{3-[3-(diethylamino)phenoxy]propoxy}phenyl)propan-1-ol and axially disubstituted silicon naphthalocyanines (SiNc) bearing electropolymerizable bis-[(4-{3-[3-(dimethylamino)phenoxy]propoxy}phenyl)propanoxy] and bis-[(4-{3-[3-(diethylamino)phenoxy]propoxy}phenyl)propanoxy] units were synthesized for the first time. Aggregation behavior of SiNcs was examined in different solvents and concentrations in DMSO. In all solvents and concentrations, SiNcs were non-aggregated. Also, electrochemical studies of SiNcs were investigated by cyclic and square wave voltammetry. While SiNcs gave only naphthalocyanine-based reduction process during the cathodic potential scans, they were electropolymerized on the working electrode during the anodic potential scan because of the oxidative electropolymerization of (4-{3-[3-(dimethylamino)phenoxy]propoxy}phenyl)propanoxy and (4-{3-[3-(diethylamino)phenoxy]propoxy}phenyl)propanoxy groups on the substituents of the complexes. 相似文献
63.
Özge Dağlı Dursun Ali Köse Gülçin Alp Avcı Onur Şahin 《Journal of Thermal Analysis and Calorimetry》2017,129(3):1389-1402
Coordination complexes of transition metal cations (CoII, NiII, CuII and ZnII) containing coumarilate and N,N′-diethylnicotinamide were synthesized. The structural characterization and thermal behaviour analysis of novel samples synthesized were conducted through elemental analysis, magnetic susceptibility, solid-state UV–Vis, direct and injection probe mass spectra, FTIR spectra, thermoanalytic TG-DTG/DTA and single crystal X-ray diffraction methods. The structural details of single crystals of [Co(dena)2(H2O)4](coum)2 (I) and [Cu(coum)2(dena)2(H2O)2] (III) complexes were resolved completely. Moreover, the results of analysis obtained for [Ni(coum)2(dena)2(H2O)2] (II) and [Zn(dena)2(H2O)4](coum)2 (IV) complexes were interpreted considering the samples with crystal structures defined and made assumptions about the structural details. It was determined that the complex of CoII metal cation has salt-type structure and the coordination number of metal is accomplished to six as the sum of 4 mol of water and also 2 mol of N,N′-diethylnicotinamide ligands in trans position located within the coordination sphere. It was observed that 2 mol of coumarilate anions are located outside the coordination sphere and have stabilized to the charge (2+) of metal. The CuII complex has totally molecular structure, and the coordination sphere of metal cation was 6 as the sum of 2 mol of water, 2 mol of N,N′-diethylnicotinamide and 2 mol of monoanionic monodentate coumarilate ligands. All ligands have been located in –trans position. The geometry of both complex structures is distorted octahedral. It is assumed that the NiII complex structure is isostructural with CuII complex structure and also does ZnII complex with CoII structure. It was determined that the decomposition products obtained from thermal analysis are the oxides of related metal cations. 相似文献
64.
65.
The aim of this study depends on understanding the effect of target‐to‐substrate distance (DTS) on ZnO thin films deposited by r.f. magnetron sputtering on to glass substrates at room temperature conditions. The DTS was changed from 35 mm to 65 mm with steps of 5 mm at 165 W and 0.2 Pa. The deposition rate of the films were ranged from 76 Ǻ / min to 146 Ǻ / min, while 10‐3 Ω.cm was obtained as the resistivity value with the help of four point probe technique. The structural investigations were carried out by using both the x‐ray diffraction (XRD) and high resolution transmission electron microscopy. According to XRD observations, the films were (002) oriented. Surface behaviour of the ZnO films was examined with atomic force microscopy and scanning electron microscopy. The root mean square (RMS) values were varied from 4.6 nm to 22.8 nm. Also, optical properties were obtained from UV–visible spectrophotometer and the transmittances as around 80 %. At 45 mm DTS value, the minimum resistivity measured as 9 × 10− 4 Ω.cm with 76 Ǻ / min deposition rate. The RMS was obtained as 4.9 nm and transmission was measured as 85.30 %, while band gap was 3.45 eV. 相似文献
66.
Gülsiye Öztürk Hasan Karabıyık Muhittin Aygün Serap Alp Serdar Özçelik 《Journal of fluorescence》2013,23(4):733-744
The solvatochromic and spectral properties of oxazolone derivatives in various solvents were reported. Fluorescence spectra clearly showed positive and negative solvatochromism depending on substituents. The solvatochromic plots and quantum chemical computations at DFT-B3LYP/6-31?+?G(d,p) level were used to assess dipole moment changes between the ground and the first excited singlet-states. The electron accepting nitro substituent at the para-position increased the π-electron mobility, however, the 3,5-dinitro substituent decreased the π-electron mobility as a result of inverse accumulation of the electronic density as compared with that of its ground state. Experimental and computational studies proved that the photoinduced intramolecular electron transfer (PIET) is responsible for the observed solvatochromic effects. We demonstrate that PIET can be finely tailored by the position of the electron accepting and donating substituents in the phenyl ring of the oxazolone derivatives. We propose that the photoactive CPO derivatives are new molecular class of conjugated push-pull structures using azlactone moiety as the π-conjugated linker and may find applications in photovoltaic cells and light emitting diodes. 相似文献
67.
R. Sevin?ek G. ?ztürk M. Aygün S. Alp O. Büyükgüng?r 《Journal of Structural Chemistry》2011,52(2):405-411
A novel oxazole-5-one derivative 2-o-tolyl-4-(3-N,N-dimethylaminophenylmethylene)-oxazol-5-one (TDPO) C19H18N2O2 is synthesized and characterized and the crystal structure is determined by X-ray crystallography. TDPO is monoclinic in
the P21/c space group. The molecule adopts the Z configuration. To enlighten the flexibility of TDPO, the selected torsion angle is
varied from −180° to 180° in each 10° separately, and the molecular energy profile is calculated and analyzed by density functional
calculations. In addition, Bader’s QTAIM analysis is performed to investigate the intramolecular weak interactions. 相似文献
68.
69.
70.
Li J Peng Q Barabanschikov A Pavlik JW Alp EE Sturhahn W Zhao J Schulz CE Sage JT Scheidt WR 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(40):11178-11185
We report our studies of the vibrational dynamics of iron for three imidazole-ligated oxyheme derivatives that mimic the active sites of histidine-ligated heme proteins complexed with dioxygen. The experimental vibrational data are obtained from nuclear resonance vibrational spectroscopy (NRVS) measurements conducted on both powder samples and oriented single crystals, and which includes several in-plane (ip) and out-of-plane (oop) measurements. Vibrational spectral assignments have been made through a combination of the oriented sample spectra and predictions based on density functional theory (DFT) calculations. The two Fe-O(2) modes that have been previously observed by resonance Raman spectroscopy in heme proteins are clearly shown to be very strongly mixed and are not simply either a bending or stretching mode. In addition, a third Fe-O(2) mode, not previously reported, has been identified. The long-sought Fe-Im stretch, not observed in resonance Raman spectra, has been identified and compared with the frequencies observed for the analogous CO and NO species. The studies also suggest that the in-plane iron motion is anisotropic and is controlled by the orientation of the Fe-O(2) group and not sensitive to the in-plane Fe-N(p) bonds and/or imidazole orientations. 相似文献