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41.
The title compound 7-acetamido-5-chloro-8-(p-methyloxybenzenesulfonyloxy)-2- styrylquinoline 4 (C26H21ClN2O5S, Mr = 508.96) has been synthesized and characterized by 1H- NMR, IR, ESI-MS and single-crystal X-ray diffraction techniques. The crystal belongs to orthorhombic, space group Pca21, with a = 7.920(3), b = 10.672(5), c = 28.008(12) , V = 2367.3(17) 3, Z = 4, Dc = 1.425 g/cm3, μ = 0.290 mm-1, F(000) = 1056, R = 0.0323 and wR = 0.0692 for 3895 unique reflections with 3127 observed ones (I > 2σ(I)). X-ray analysis reveals that the styrylquinoline subunit adopts a coplanar conformation, where the benzene ring and quinoline are in trans configuration.  相似文献   
42.
One novel polyoxometalate compound connected via trivalent cerium cation as bridge H2{[K(H2O)2]2[Ce(H2O)5]2(H2Mo1.16W10.84O42)}·8H2O 1 was designed and synthesized in aqueous solution. X-ray diffraction analysis reveals that the structure of 1 is a three-dimensional framework assembled from the arrangement of H2Mo1.16W10.84O42 (named paradodecmetalate-B) and Ce(H2O)53 containing two planes, which are constructed through the unification of H2Mo1.16W10.84O4210- and Ce(H2O)53 along the [100] and [001] directions. Crystal data: H96Ce4K4Mo2.32O128W21.68, Mr = 7074.89, monoclinic, P21/n, a = 12.5037(17), b = 17.002(2), c = 12.7473(17) (A), β = 105.966(2)°, V = 2605.4(6) (A)3, Z = 1, Dc = 4.509 g/cm3, F(000) = 3132, μ = 26.098 mm(1, R = 0.0377 and wR = 0.0789 (I > 2σ(I)).  相似文献   
43.
The title compound [Mn(O2CMe)2(phen)2] (phen = 1,10-phenanthroline) 1 has been synthesized and structurally determined by single-crystal X-ray diffraction. The crystal is of orthorhombic, space group Pbcn, with a = 12.554(4), b = 10.168(3), c = 17.704(5) (A), V = 2259.7(12) (A)3, Z = 4, C28H22MnN4O4, Mr = 533.44, Dc = 1.568 g/cm3, F(000) = 1100, Rint = 0.0242, T = 293(2) K and μ = 0.631 mm-1. The final R = 0.0687 and wR = 0.1960 for 2046 observed reflections with I > 2σ(I). The structure of the complex consists of one Mn(Ⅱ) core coordinated by two bidentate-bound CH3COO- groups and two η2-phen groups forming an eight-coordinate geometrical configuration.  相似文献   
44.
5-O-Benzoyl-1,2-O-isopropylidene-α-D-erythro-ketofuranose-3-ulose-3-aminothiose 3 was synthesized and characterized by spectral analysis, and its crystal structure was determined by X-ray diffraction analysis. The crystal belongs to orthorhombic, space group P212121 with a = 6.6276(13), b = 10.993(2), c = 25.027(5) , β = 90°, V = 1823.4(6)3, Z = 4, C16H20N3O5S, Mr = 366.41, Dc = 1.335 g/cm3, μ = 0.208 mm-1, F(000) = 772, S = 1.007, the final R = 0.0465 and wR = 0.1061 for 3251 observed reflections (I > 2σ(I)). Four hydrogen bonds are observed. The absolute configuration of this molecule was confirmed by comparing with that of the original material.  相似文献   
45.
A novel one-dimensional chain-like coordination polymer constructed from 3-nitrobenzene-1,2-dicarboxylic acid, [Cd2(C8H3NO6)2(H2O)4]n·2nH2O, has been synthesized and its structure was determined by X-ray crystallography method. The crystal belongs to monoclinic, space group P21/c with a = 6.1252(8), b = 20.706(3), c = 8.8067(11) (A), β = 95.608(2)°, V= 1111.6(2)(A)3, Mr =751.12, Dc = 2.244 g/cm3, F(000) = 736, μ = 2.011 mm-1, Z = 2, the final R = 0.0262 and wR = 0.0692for 2338 observed reflections with I > 2σ(I). The structure of the title compound presents a 1-D chain-like structure constructed by dimer units, [Cd2(CsH3NO6)2(H2O)4]n, through two carboxylate oxygen atoms. The fluorescence of the tifle compound has been also discussed in this paper.  相似文献   
46.
The title compound,[Cu2(CH3COO)4(C8H10N2)]n·nCH3CN1 (C8H10N2,4,4'-bipy = 4,4'-bipyridine),has been solvothermally synthesized in CH3CN and characterized by X-ray diffraction.The crystal is of monoclinic,space group Cc with a = 22.626(6),b = 14.012(4),c =15.106(4) (A),β = 107.610(3)°,V = 4565(2) (A)3,C20H23Cu2N3O8,Mr = 560.49,Z = 8,Dc = 1.631 g/cm3,μ = 1.914 mm-1,Flack parameter = 0.48(1),F(000) = 2288,R = 0.042 and wR = 0.)98 for 8887 observed reflections (I > 2σ(I)).It consists of nearly linear one-dimensional chains [Cu2(CH3COO)4(C8H10N2)]n derived from paddle-wheel [Cu2(CH3COO)4] unit linked by 4,4'-bipy,and CH3CN as guest molecule regularly decorates between the chains.  相似文献   
47.
建立了超高效液相色谱-静电场轨道阱高分辨质谱(UPLC-Orbitrap HRMS)同时测定合成革中8种异氰酸酯残留的方法。样品中残留的异氰酸酯经二氯甲烷超声萃取后,用9-甲氨基甲基蒽(MAMA)进行衍生,衍生产物浓缩定容后进行UPLC-Orbitrap HRMS分析,外标法定量。衍生产物在Hypersil GOLD色谱柱(100 mm×2.1 mm,1.9 μm)上进行分离,流动相为乙腈-0.1%(v/v)甲酸水溶液,采用电喷雾正离子(ESI+)模式电离,以保留时间和准分子离子精确质量数定性,以提取离子色谱峰面积定量。各组分的定量限均为0.2 μg/kg,在3个加标浓度水平下,方法的平均加标回收率为85.41%~95.53%,相对标准偏差(RSD)为2.55%~6.87%。应用该方法对市售合成革产品进行监测,结果在1个样品中检出了异佛尔酮二异氰酸酯。该方法定性准确,定量限低,灵敏度高,可用于合成革中异氰酸酯残留的测定。  相似文献   
48.
Newly synthesized proteins constitute an important subset of the proteome involved in every cellular process, yet existing chemical tools used to study them have major shortcomings. Herein we report a suite of cell‐permeable puromycin analogues capable of being metabolically incorporated into newly synthesized proteins in different mammalian cells, including neuronal cells. Subsequent labeling with suitable bioorthogonal reporters, in both fixed and live cells, enabled direct imaging and enrichment of these proteins. By taking advantage of the mutually orthogonal reactivity of these analogues, we showed multiplexed labeling of different protein populations, as well as quantitative measurements of protein dynamics by fluorescence correlation spectroscopy, could be achieved in live‐cell environments.  相似文献   
49.
刘胜男  陈高  孟健 《物理学报》2012,61(14):143201-143201
通过数值求解一维含时Schrödinger方程,研究了具有较长脉宽双色激光脉冲与氢原子相互作用产生的高次谐波和阿秒(as)脉冲.这里的双色激光脉冲由一束基频钛宝石主脉冲与另一束红外附加脉冲构成.研究发现,当合成脉冲的脉宽选为12 fs时, 选取合适的附加脉冲波长,合成电场的振幅在始末端时间段能被大幅抑制, 仅中间部分的电场对谐波谱平台区和截止位置起主要贡献. 通过分析合成脉冲电场始末端时间段抑制的机理,进一步扩展了合成脉冲脉宽到60 as, 并得到160 as的孤立短脉冲.这是迄今为止在孤立阿秒脉冲产生研究中所采用的最长脉宽. 该方案中的合成脉冲等效于单一5 fs短脉冲的作用, 却克服了5 fs脉冲低输出能量导致的阿秒脉冲能量低的困难.  相似文献   
50.
延凤平  刘鹏  谭中伟  陶沛琳  李琦  彭万敬  冯亭  谭思宇 《物理学报》2012,61(16):164202-164202
提出一种利用组合透镜系统与渐变折射率光纤相结合改进激光 器管芯到单模尾纤耦合性能的新方法. 这种方法首先利用组合透镜系统对具有像 散的激光器输出光束进行整形, 然后采用渐变折射率光纤对整形后的光束进行聚焦处理, 并将处理后的的光束耦合进入普通单模光纤. 利用Jones矩阵理论分析表明, 采用这种方法可以得到86%的功率耦合效率, 1 dB插入损耗对应的渐变折射率光纤长度、 横向偏移和倾斜角容差分别为60 μm, 30 μm和2.4°, 且结构简单, 便于操作, 特别适合于大功率激射的激光模块到单模光纤的耦合. 对于提高激光器输出功率, 改善光束质量具有重要意义.  相似文献   
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