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91.
Ming Ze Wu Zhi Long Ma Jian Yun Shi Xiu Juan Shi 《Journal of Coordination Chemistry》2019,72(22-24):3495-3501
AbstractSolvothermal reaction of a multidentate ligand (tetrakis[4-(1-triazolyl)phenyl]-methane (ttpm)), with Cd(NO3)2 afforded a cationic Cd(II) coordination polymer {[Cd(ttpm)·DMSO]·2NO3}n. Single-crystal X-ray diffraction analyses showed that ttpm belonged to the tetragonal space group I41/a, and 1 was a 2-D (4,4) network. 1-D channels along the c direction exist in the 3D stacking map to accommodate the charge-balancing NO3? anions. N2 adsorption/desorption experiments showed the framework had a BET surface area of 11.36?m2·g?1. Compared with luminescence of ttpm, 1 showed red-shifted luminescence spectra with higher intensity from the more rigid arrangement of the π systems. 相似文献
92.
93.
在碘化亚铜、四丁基溴化铵和磷酸钾存在下,9,9-二(4-羟基苯基)呫吨(1)和4-甲基碘苯(2)于N,N-二甲基甲酰胺溶剂中发生Ullmann偶联反应,加热回流反应24 h,以95%的产率合成了中间体--9,9-二[4-(4-甲基苯氧基)苯基]呫吨(3),继而加入催化量的N-溴代丁二酰亚胺并在光照条件下,将中间体3氧化得到一种新型芳香族二羧酸--9,9-二[4-(4-羧基苯氧基)苯基]呫吨(4),其产率为84%,二步反应总收率为79.8%。 目标化合物4经1H NMR、13C NMR、IR和元素分析测试技术确定了其结构。 该法具有原料易得,操作简单,反应条件温和,收率高等优点。 相似文献
94.
Computational design and screening of promising energetic materials: Novel azobis(tetrazoles) with ten catenated nitrogen atoms chain 下载免费PDF全文
Piao He Jian‐Guo Zhang Le Wu Jin‐Ting Wu Tong‐Lai Zhang 《Journal of Physical Organic Chemistry》2017,30(10)
Density functional theory methods were used to study on 2 N10 compounds, 1,1′‐azobis(tetrazole) and 1,1′‐azobis(5‐methyltetrazole). We systematically investigated 10 novel substituted azobis(tetrazoles) with 10 catenated nitrogen atoms and various energetic groups (–CF3 1 , –C(NO2)3 3 , –N3 5 , –NH2 6 , –NHNH2 7 , –NHNO2 8 , –NO2 9 , –OCH3 10 , –OH 11 , –ONO2 12 ). The optimized geometry, frontier molecular orbitals, electrostatic potential, Infrared and nuclear magnetic resonance spectrum were calculated for inspecting the molecular structure and stability as well as chemical reactivity. The effects of different substituents on the density, enthalpy of formation, heat of explosion, detonation velocity and pressure, and sensitivity of the azobis(tetrazole) derivatives have been investigated. Compound 9 with nitro was found to have remarkable detonation performances (D = 9.61 km/s, P = 42.14 GPa), which are close to the excellent explosive CL‐20. Results show that compounds 1 , 3 , 4 , 7 , 9 , 11, and 12 have high potential to replace RDX. It is surprising that compounds 1 , 3 , 9, and 12 possess better energetic properties than HMX. These novel substituted azobis(tetrazoles) with unique N10 structure may be promising candidates of HEDMs with outstanding performance and acceptable sensitivities. 相似文献
95.
Anilinolysis of O‐butyl phenyl phosphonochloridothioate in acetonitrile: Synthesis,characterization, kinetic study,and reaction mechanism 下载免费PDF全文
This paper describes a simple optimized method for the synthesis of O‐butyl phenyl phosphonochloridothioate ( 4 ) under mild conditions. The target compounds were characterized by 1H‐nuclear magnetic resonance (NMR), 13C‐NMR, and 31P‐NMR spectroscopy, as well as mass spectroscopy. The apparent structure of 4 was confirmed by optimization using the B3LYP/6‐311 + G(d,p) level in the Gaussian 09 program in acetonitrile. The nucleophilic substitution reactions of 4 with X‐anilines (XC6H4NH2) and deuterated X‐anilines (XC6H4ND2) were investigated kinetically in acetonitrile at 55.0°C. The free energy relationship with X in the anilines looked biphasic concave upwards with a break region between X = H and X = 3‐MeO, giving large negative ρX and small positive βX values. The deuterium kinetic isotope effects were secondary inverse (kH/kD < 1: 0.789‐0.995) and the magnitudes, (kH/kD), increased when the nucleophiles were changed from weakly basic to strongly basic anilines. A concerted SN2 mechanism is proposed on the basis of the selectivity parameters and the variation trend of the deuterium kinetic isotope effects with X. 相似文献
96.
Franco M. Rabagliati Mónica A. Pérez Francisco J. Rodríguez Rodrigo A. Cancino Nocolas Crispel Gabriela A. Mardones Héctor E. Muñoz Marcela A. Saavedra Manuel Vidal Lisa A. Muñoz 《Macromolecular Symposia》2011,304(1):33-39
Summary: Binary metallocene-MAO and ternary diphenylzinc-metallocene-MAO initiator systems have been tested as initiators in the homopolymerization of styrene and also in its copolymerization with several diverse comonomers including substituted styrenes, styrene derivatives, α-olefins and dienes. Various titanocenes and zirconocenes and some exploratory experiment with hafnocene were carried out. The results indicate that titanocenes were more effective than zirconocenes in the homopolymerization of styrene while zirconocenes did better in α-olefin polymerization. It was found that titanocenes generated mainly syndiotactic polystyrene, s-PS, while zirconocenes yielded atactic polystyrene or, depending on the zirconocene, a low percentage of s-PS. For these types of initiators the polymerization process depends largely on the inductive effect of the substituents linked to the benzene ring of styrene and on its position (ortho, meta or para). Substituent multiplicity reduced markedly the effectiveness of these initiator systems. Styrene/isoprene polymerization was also studied using binary zirconocene-MAO initiator systems that yielded low conversions and also low molecular weight polymers. 相似文献
97.
The synthesis and characterization of a series of heterocyclic liquid crystal, 4-{[(thiophen-2-yl)methylidene]amino}phenyl 4-alkoxybenzoates possessing even number of carbon atoms at the alkoxy chain (CnH2n+1O-, n = 6, 8, 10, 12, 14, 16, 18) are reported. The molecular structures of title compounds were elucidated using Fourier-transform infrared spectroscopy (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopic techniques along with mass spectrometric analysis. The phase behavior of these compounds was characterized and studied by differential scanning calorimetry and polarizing optical microscopy. All members exhibited enantiotropic nematic phase except for the highest member (n = 18) which is a non-mesogen. Influence of alkoxy chain length on the transition temperatures of crystal-to-nematic (melting point) and nematic-to-isotropic (clearing point) was studied. Nematic phase range was found to increase from n = 6 to n = 10, then it started to descend from n = 12 to n = 16 and finally the nematic phase disappeared when n changed to 18. 相似文献
98.
Phenyl‐modified natural rubber was prepared in latex stage by bromination of deproteinized natural rubber followed by Suzuki‐Miyaura cross‐coupling reaction. First, the bromination of natural rubber was carried out using N‐bromosuccinimide in latex stage. The bromine atom content increased as amount of N‐bromosuccinimide increased. Second, the allylic bromine atom was replaced with a phenyl group using phenyl boronic acid in the presence of a palladium catalyst, according to the Suzuki‐Miyaura cross‐coupling reaction in latex stage. The resulting products were characterized by nuclear magnetic resonance (NMR) spectroscopy. Signal at 7.13 ppm was assigned to the phenyl group of the product, while signals at 3.98, 4.14, and 4.44 ppm were assigned to the remaining allylic brominated cis‐1,4‐isoprene units. The estimated phenyl group content and the conversion of the Suzuki‐Miyaura cross‐coupling reaction were 1.32 and 23.7 mol%, respectively. Glass transition temperature (Tg) of deproteinized natural rubber increased from ?62°C to ?46.7°C, when the phenyl group was introduced into the rubber. 相似文献
99.
Dr. Ruihao Xie Prof. Dr. Lei Ying Kang An Wenkai Zhong Qingwu Yin Shengzu Liao Prof. Dr. Fei Huang Prof. Dr. Yong Cao 《Chemphyschem》2019,20(20):2668-2673
Two wide-bandgap polymer donors containing an alkylthiophenyl substituted benzo[1,2-b : 4,5-b′]dithiophene moiety, namely PTZPO and PTZPS, were designed and synthesized. Both polymers exhibit relatively wide optical bandgap of 1.95 V with similar absorption profiles. The polymer PTZPS with alkylthiophenyl substituted benzo[1,2-b : 4,5-b′]dithiophene units showed enhanced light-harvesting capabilities, leading to improved short-circuit current densities. The PTZPS : ITIC film shows more appreciable film morphology and phase separation than the film composed of a blend of ITIC with alkoxyl substitutions containing copolymer PTZPO, which facilitates exciton dissociation and charge transport. The PTZPS : ITIC-based non-fullerene organic solar cells show clearly improved short-circuit current density and an impressively high power conversion efficiency of more than 11 %. These observations demonstrate the great promise of using PTZPS as electron-donating materials for high-performance non-fullerene organic solar cells. 相似文献
100.
P. P. Pershukevich I. K. Shushkevich E. A. Makarova K. N. Solov’eva 《Journal of Applied Spectroscopy》2008,75(5):706-713
We have studied the spectral luminescence properties of a zinc complex of dibenzobarreleno-substituted tetraazaisobacteriochlorin
(a synthetic tetrapyrrole pigment which is the structural analog of the biologically important chromophore isobacteriochlorin)
and a palladium complex of dibenzobarreleno-substituted tetraazachlorin. We have shown that despite the substantial effect
of aza-substitution on the electronic structure and the electronic spectra of the tetrapyrrole molecules, the effect of hydrogenation
of adjacent pyrrole rings on the spectral luminescence properties is similar in compounds with nitrogen and carbon bridges.
As in the free base case, the fluorescence of the studied zinc complex is strongly quenched at 293 K but flares up at 77 K
(temperature and viscosity-dependent quenching). To study the substituted Zn-tetraazaisobacteriochlorin, we determined the
position of the 0-0 band of the low-intensity transition S0 → S2 and showed that the S2 → S1 energy difference increases with bridge aza substitution. For the Pd complex of dibenzobarreleno-substituted tetraazachlorin,
we could not detect phosphorescence in the near IR region (to 1150 nm); we detected weak fluorescence.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 75, No. 5, pp. 700–707, September–October, 2008. 相似文献