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91.
环己酮肟在B2O3/Al2O3-TiO2催化剂上的气相Beckmann重排反应 总被引:1,自引:0,他引:1
制备了B2O3/Al2O3-TiO2复合载体催化剂,并考察了其对环己酮肟气相Beckmann重排制己内酰胺反应的催化性能. 结果表明,载体中TiO2的含量、B2O3的负载量、载体的预处理温度及催化剂的焙烧温度等均对催化剂的性能产生明显的影响. 当载体中TiO2含量为60%,B2O3负载量为20%,催化剂经350 ℃焙烧时,环己酮肟的气相Beckmann重排反应的转化率和选择性很高. 用BET,NH3-TPD,XRD和IR等方法对催化剂的织构、表面酸性和晶相等进行了表征,并与催化剂的活性进行了关联,表明催化剂表面中等强度的酸中心浓度与催化剂的选择性具有对应关系. 相似文献
92.
Serhii A. Liakhov Igor A. Schepetkin Olexander S. Karpenko Hanna I. Duma Nadiia M. Haidarzhy Liliya N. Kirpotina Anastasia R. Kovrizhina Andrei I. Khlebnikov Irina Y. Bagryanskaya Mark T. Quinn 《Molecules (Basel, Switzerland)》2021,26(18)
c-Jun N-terminal kinase (JNK) plays a central role in stress signaling pathways implicated in important pathological processes, including rheumatoid arthritis and ischemia-reperfusion injury. Therefore, inhibition of JNK is of interest for molecular targeted therapy to treat various diseases. We synthesized 13 derivatives of our reported JNK inhibitor 11H-indeno[1,2-b]quinoxalin-11-one oxime and evaluated their binding to the three JNK isoforms and their biological effects. Eight compounds exhibited submicromolar binding affinity for at least one JNK isoform. Most of these compounds also inhibited lipopolysaccharide (LPS)-induced nuclear factor-κB/activating protein 1 (NF-κB/AP-1) activation and interleukin-6 (IL-6) production in human monocytic THP1-Blue cells and human MonoMac-6 cells, respectively. Selected compounds (4f and 4m) also inhibited LPS-induced c-Jun phosphorylation in MonoMac-6 cells, directly confirming JNK inhibition. We conclude that indenoquinoxaline-based oximes can serve as specific small-molecule modulators for mechanistic studies of JNKs, as well as potential leads for the development of anti-inflammatory drugs. 相似文献
93.
94.
Three new oxime‐based palladacycles, namely [Pd{C,N‐C6H4{C(Me)?NOH}‐2}(dppm)]ClO4 ( 1 ), [Pd2{C,N‐C6H4{C(Me)?NOH}‐2}2(dppe)2(μ‐dppe)](ClO4)2 ( 2 ) and [Pd{C,N‐C6H4{C(Me)?NOH}‐2}(dppmS2)]ClO4 ( 3 ), were synthesized by the reaction of dinuclear oxime complex [Pd{C,N‐C6H4{C(Me)?NOH}‐2}(μ‐Cl)]2 with different diphosphine ligands (dppm, dppe and dppmS2). The synthesized complexes were characterized using Fourier transform infrared, 31P NMR, 1H NMR and 13C NMR spectroscopic methods and elemental analyses, and their molecular structures were elucidated using X‐ray crystallography. The structure of 2 is worthy of note as it is the first oxime palladacycle where there are both bridging (P–) and chelating (P^P) dppe ligands, giving rise to a dinuclear complex. The palladium atom is in a five‐coordinate, square pyramidal P3NC environment, while in 3 the palladium atom is in a distorted square planar environment, coordinated by the oxime ligand and a chelating (S^S) dppmS2 ligand. These complexes were employed as efficient catalysts for the Suzuki–Miyaura cross‐coupling reaction of several aryl bromides with phenylboronic acid. The in vitro cytotoxicity of the compounds was also evaluated against human tumour cell lines (HT29, A549 and HeLa) using the MTT assay method. The results indicate that the dinuclear complex 2 has greater catalytic and anticancer activity in comparison with the mononuclear complexes 1 and 3 . 相似文献
95.
J. Nurit J. M. Leloup B. Pauvert O. Doumbia P. Chevallet A. Térol 《Journal of Thermal Analysis and Calorimetry》1995,45(3):535-558
The infrared,1H NMR and X-ray diffraction characteristics of a series of 3-(α-hydroxy-imino-aryl)-1,2,2-trimethyl cyclopentane carboxylate are reported. The thermal analysis of this series has been studied by differential scanning calorimetry. The results show a large variety of thermal behaviours with some of the compounds exhibiting polymorphism and the two types of isomers were detected. 相似文献
96.
Development of a Novel Homogeneous and Heterogeneous Pd Catalytic System for Organic Transformations
The results of our new finding on homogeneous and heterogeneous palladium catalytic system for oxidation of alcohols and alkenes using molecular oxygen are described together with several successful attempts to make the system recyclable from the viewpoint of environmental and economical concerns. In addition, some novel organic transformations of tert-cyclobutanols and cyclobutanone oximes are also presented where -carbon elimination involving C–C bond fission is a key step. 相似文献
97.
《无机化学与普通化学杂志》2018,644(12-13):585-589
The reaction of Hppko (Hppko = phenyl 2‐pyridyl ketone oxime) and CoCl2 · 6H2O in the CH3OH solvent with the presence of triethylamine (NEt3) at room temperature and the exposure to air resulted in the formation of a new pentanuclear, mixed‐valence cobalt complex with the molecular formula [{CoII(CH3O)3}2{CoIII3(μ3‐O)(ppko)3}Cl2]. X‐ray single crystal analysis displays a trigonal bipyramid configuration with the terminal two CoII ions wrapping an triangle [CoIII3O]7+ core. The intermolecular C–H ··· O and C–H ··· Cl interactions form a 2D network framework. The analysis of magnetic susceptibility revealed the dominant antiferromagnetic interactions and strong orbital contribution of CoII ions. 相似文献
98.
Lorena Martínez Livia Arizaga Donatella Armentano Francesc Lloret Ricardo González Carlos Kremer 《Journal of Coordination Chemistry》2018,71(6):748-762
AbstractTwo new mixed-valence iron complexes with 2-pyridyl oximes, [Fe(mpko)3Fe(H2O)2(NO3)](NO3)·2H2O (1) (mpko? = methyl(2-pyridyl)ketone oximate) and [{Fe(dpko)3}2Fe](ClO4)·4H2O (2) (dpko? = bis(2-pyridyl)ketone oximate), have been prepared by reaction of FeIII with mpkoH in methanol (1) and FeII with dpkoH in methanol/water (2). Dinuclear FeII(low-spin)FeIII(high-spin) and trinuclear FeII(low-spin)FeIII(high-spin)FeII(low-spin) cations are present in the crystal structure of 1 and 2, respectively. Intermolecular hydrogen bonds in 1 lead to weak antiferromagnetic interactions between pairs of neighboring FeIII centers, which allows observation of single-ion zero-field splitting effects. 相似文献
99.
100.
Sung Yun Cho Seung Kyu Kang Jin Hee Ahn Jae Du Ha Joong-Kwon Choi 《Tetrahedron letters》2006,47(51):9029-9033
A convenient and facile one-pot synthesis of 5,6-dihydro-4H-[1,2,4]oxadiazine is described. Treatment of aziridin-1-yl-oximes with Scandium(III) triflate readily afforded 5,6-dihydro-4H-[1,2,4]oxadiazine in the presence of chlorotrimethylsilane. 相似文献