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排序方式: 共有157条查询结果,搜索用时 281 毫秒
51.
A new cadmium (II) coordination polymer, [Cd(TTTMB)2]‐(SO4) · 21H2O, where TTTMB =1,3, 5‐tris (imidazol‐1‐yl‐methyl)‐2,4,6‐trimethylbenzene, was obtained by self‐assembly of tripodal ligand TTTMB with CdSO4·2.7H2O in acetonitrile, and characterized by X‐ray crystallography. The crystal data belongs to monoclinic space group Cc with cell parameters a = 1.16891(4) nm, b=2.06671(6) nm, c = 2.48185(7) nm, β = 97.8560(10)°, R = 0.0487, wR = 0.1211. The results of structure analysis indicate that each TTTMB ligand coordinates three metal atoms and in turn each Cd(II) atom with octahedral coordination geometry connects six nitrogen atoms of imidazole group from six different TTTMB ligands to produce a 2D honeycomb network structure. There are a lot of water molecules linked by hydrogen bonds and occupied the channels formed intra‐ and inter‐sheets. 相似文献
52.
Hirobumi Takahashi Takehiro Fukami Hisaki Kojima Takeru Yamakawa Hiroyuki Takahashi Toshihiro Sakamoto Teruyuki Nishimura Masayuki Nakamura Takashi Yosizumi Kenji Niiyama Norikazu Ohtake Takashi Hayama 《Tetrahedron》2005,61(14):3473-3481
A robust synthetic method for 2-alkylamino-6-carboxy-5,7-diarylcyclopenteno[1,2-b]pyridines via acylamination at the alpha position of the functionalized pyridine system has been developed. The key step in this method was achieved by treatment of the corresponding pyridine N-oxides with 2.5 equiv of imidoyl chlorides in the presence of triethylamine, thus producing the desired 2-acylaminopyridines in good yields (74-96%). 相似文献
53.
Okada Yutaka Miyamoto Norikazu Hishimoto Munemitsu Hayashi Takatoshi 《Transition Metal Chemistry》1999,24(3):258-262
Reactions between benzoferrocenes and substituted benzenes gave products resulting from intramolecular and intermolecular ligand exchange. The product ratios were influenced by the number of methyl substituents on the benzene ring; the larger the number, the greater the ratio of intermolecular products. 相似文献
54.
Man-Sheng Chen Qin Hua Zheng-Shuai Bai Taka-aki Okamura Zhi Su Wei-Yin Sun Norikazu Ueyama 《Polyhedron》2010
Four new inorganic–organic hybrid frameworks [Mn(L)(H2O)2]n (1), {[Co(L)(H2O)3]·2H2O·CH3OH}n (2), {[Zn(L)(H2O)]·H2O}n (3) and [Cd(HL)2]n (4) [H2L = 4-(isonicotinamido)phthalic acid] have been synthesized and characterized by single-crystal X-ray diffraction analysis. Complex 1 has three-dimensional (3D) structure and topology related to SrAl2 (sra) with Schläfli symbol of (42·63·8). And 2 displays (3,3)-connected two-dimensional (2D) network with (4,82) topology, while 3 exhibits a uninodal (3,3)-connected (6,3) 2D network, which is further linked by N–H?O hydrogen bonding interactions to give 3D structure with hms topology and Schläfli symbol of (63)(69·8). Complex 4 with partial deprotonated HL− ligands also has a 2D network structure. In addition, the magnetic property of 1, nonlinear optical property of 3 and photoluminescence of 3 and 4 were investigated. 相似文献
55.
Qian Chu Guang-Xiang Liu Taka-aki Okamura Yong-Qing Huang Wei-Yin Sun Norikazu Ueyama 《Polyhedron》2008
Self-assembly of a new carboxylate containing ligand, N-(3-carboxyphenyl)iminodiacetic acid (H3L), with Cd(II) and Co(II) salts under different reaction pH results in the formation of four new coordination polymers, namely [Cd(HL)(H2O)] (1), [Co(HL)(H2O)] (2), [Cd(HL)(H2O)4] (3) and [Cd3(L)2(H2O)9] · 7H2O (4). Single crystal X-ray diffraction analysis indicates that 1 and 2 are isomorphous and isostructural with a 2D wave-like network structure, while 3 has a 1D zigzag chain structure. The complexes 1–3 were obtained at low pH (<7) which makes the ligands only partly deprotonated. However, complex 4, obtained at pH 7 with all the carboxylate groups deprotonated, exhibits a 2D network structure. The results suggest that the reaction pH is one of the key factors in the formation of the coordination architectures. In addition, the photoluminescence properties of the free ligand (H3L) and complexes 1, 3 and 4 were studied in the solid state at room temperature. Moreover, the magnetic property of complex 2 was investigated. 相似文献
56.
组蛋白去乙酰化酶(HDACs)通过催化各种底物蛋白包括组蛋白、转录因子、α-微管蛋白和核输入蛋白等的ε-赖氨酸残基乙酰化侧链的去乙酰化来影响细胞功能,抑制HDAC活性可以治疗表观遗传异常引起的癌症和其他慢性疾病.以HDAC抑制剂(HDACi) Chlamydocin为骨架设计合成一类新型抑制剂,将HDACi的结合区设计为二硫键结构、在环肽中苯丙氨酸的苯环不同位点引入甲基,合成4种不同序列的环肽类HDACi.考察HDACi体外抗肿瘤细胞(MCF-7,Hela和7721)活性,结果表明HDACi对三种肿瘤细胞系均显示良好的生长抑制作用,细胞形态都发生明显变化,其中对Hela细胞的毒性最高,IC50达到0.1 μmol/L. 相似文献
57.
Qian Chu Ling‐Yan Kong Taka‐aki Okamura Hiroyuki Kawaguchi Wen‐Li Meng Wei‐Yin Sun Prof. Dr. Norikazu Ueyama 《无机化学与普通化学杂志》2007,633(2):326-331
Assembly of bidentate ligand 1‐(1‐imidazolyl)‐4‐(imidazol‐1‐ylmethyl)benzene (IIMB) with varied metal salts of ZnII, CdII and PbII provide three new complexes, [Zn(IIMB)2](ClO4)2·2H2O ( 1 ), [Cd(IIMB)2(SCN)2] ( 2 ) and [Pb(IIMB)2(SCN)](SCN) ( 3 ). Single crystal X‐ray diffraction studies revealed that complexes 1 and 2 display a similar one‐dimensional double stranded chain structure, while complex 3 is a slight distorted rhombohedral grid network with (4,4) topology. The results indicate that the coordination geometry of the metal ion and the counter anion have great impact on the structure of the complexes. In addition, the photoluminescence properties of ligand IIMB and complexes 1 – 3 were studied in the solid state at room temperature. 相似文献
58.
59.
1,3,5-苯三乙酸-钬配合物的合成、结构和磁性质研究 总被引:1,自引:0,他引:1
利用柔性三脚架配体1,3,5-苯三乙酸(H3bta)与Ho(NO3)3•6H2O在水热条件下组装得到了一个具有三维孔道结构的配位聚合物: {[Ho(bta)(H2O)]•1.26H2O}n (1). X射线单晶衍射分析表明该配合物属三斜晶系, 空间群P-1, 晶胞参数 a=0.7621(4) nm, b=0.9634(4) nm, c=1.0500(5) nm, α=106.409(18)°, β=105.273(18)°, γ=100.88(2)°, Z=2, V=0.6839(6) nm3, Dc=2.208 g/cm3, μ=5.824 mm-1, F(000)=437, R1=0.0224, wR2=0.0462. 在1.8~300 K的温度范围内研究了该配合物固体样品的磁性质. 相似文献
60.
Manabu Miyamoto Kaori Nagata Takanori Maruo Norikazu Nishiyama Katsunori Yogo Yasuyuki Egashira Korekazu Ueyama 《Journal of membrane science》2008
Mesoporous silica membranes were prepared on porous alumina substrates by a vapor infiltration of tetraethoxysilane (TEOS) into a non-ionic poly(oxyethylene) (Brij56) surfactant film. Periodic mesostructured silica membranes were formed on both α- and γ-alumina substrates pre-treated with polystyrene. The polystyrene polymer plugged the pores of the alumina substrates and inhibited the deposition of silica in the alumina pores, resulting in the formation of a very thin silica membrane without a silica/alumina composite layer at the interface between mesoporous silica and the alumina substrates. The calcined mesoporous silica membrane showed very high nitrogen permeance (>10−6 mol m−2 s−1 Pa−1). The single gas permeation was governed by the Knudsen diffusion mechanism. The durability of the mesoporous silica membrane against moisture in air was improved by a silylation with trimethylethoxysiliane. 相似文献