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71.
Two luminescent Co(II)-based coordination polymers (CPs) with the formulae of [Co(L1)(1,4-ndc)·H2O]n (CP 1) and [Co2(L2)(1,4-chdc)2]n (CP 2) (L1?=?1,1′-(1,4-butanediyl)bis(5,6-dimethylbenzimidazole), 1,4-H2ndc?=?1,4-naphthalenedicarboxylic acid, L2?=?1,1′-(1,4-butanediyl)bis(2-methylbenzimidazole), 1,4-H2chdc?=?1,4-cyclohexanedioic acid) have been synthesized. Both CPs were characterized by single-crystal X-ray diffraction, thermogravimetric analysis, elemental analysis, IR spectroscopy, and powder X-ray diffraction. CP 1 reveals a 2D 3,5L2 framework, while CP 2 has a 2D (4,5)-connected 4,5L51 network. Both CPs are luminescent and can be employed for the selective detection of free MnO4? in water.  相似文献   
72.
由三齿配体2,6-二[1-(2-甲基苯基亚胺)乙基]吡啶(L1)和2,6-二[(1-苯基亚胺)乙基]吡啶(L2)分别与NiCl2.6H2O在乙腈中反应,合成了两个吡啶二亚胺基氯化镍配合物L1Ni(Ⅱ)Cl2.CH3CN(1)和L2Ni(Ⅱ)Cl2(2).通过元素分析、IR和1HNMR对配体和配合物进行了结构表征,并测定了配合物1和2的晶体结构.X射线衍射分析结果表明,两个配合物均为五配位扭曲三角双锥构型,属单斜晶系,Cc空间群.配合物1的晶胞参数a=2.5783(5)nm,b=1.4843(3)nm,c=1.5866(3)nm;β=122.82(3),°V=5.1024(18)nm3,Z=4,R1=0.0708,配合物2的晶胞参数a=1.5772(1)nm,b=0.8594(1)nm,c=1.5459(1)nm;β=103.27(1),°V=2.039(2)nm3,Z=4,R1=0.0375.配合物1和2经MAO活化后对乙烯聚合表现出较低的催化活性.  相似文献   
73.
The molecular geometries, frontier molecular orbital properties, and absorption and emission properties of three 4-phenoxy-1,8-naphthalimide derivatives, namely 4-phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide(1),4-(2-tert-butylphenoxy)-N-(2-hydroxyethyl)-1,8-naphthalimide(2), and 4-[2,4-di(tert-butyl)]phenoxy-N-(2-hydroxyethyl)-1,8-naphthalimide(3), are investigated by density functional theory(DFT) and time-dependent density functional theory(TD-DFT) calculations in conjunction with polarizable continuum models(PCMs). Four functionals and ten basis sets are employed for 1 to calculate the electron transition energies, which were compared with the experimental observations. Our results reveal that the B3LYP/6-311+G(d,p) method is the best choice to reproduce the experimental spectra. Moreover, the effects of substituents on the molecular geometries, electronic structures, absorption and emission spectra are also studied at the B3LYP/6-311+G(d,p) level. We find that the gap between the highest occupied molecular orbital(HOMO) and the lowest unoccupied molecular orbital(LUMO) decreases with increasing the number of tert-butyl substituents onto the phenoxy groups, suggesting red-shift of the absorption and emission bands. This is related to the increase of conjugation from 1 to 2 and 3. Our calculations are in good agreement with the experimental results.  相似文献   
74.
在中温混合溶剂热条件下合成了两个金属铜配位聚合物Cu3(2,2′-bipy)2(C8H4O4)2(C8H5O4)2和Cu(Ⅰ)Cu(Ⅱ)(4,4′-bipy)1.5(C8H4O4)(C8H5O4)(bipy=联吡啶,C8H4O4=1,3-间苯二甲酸),并对其进行了单晶结构解析及相关性能表征.配合物Cu3(2,2′-bipy)2(C8H4O4)2(C8H5O4)2(1)晶体属三斜晶系,P1空间群,a=1.03314(4)nm,b=1.08350(3)nm,c=1.15826(4)nm,α=83.104(2)°,β=84.609(2)°,γ=66.125(2)°,Z=1.配合物Cu(Ⅰ)Cu(Ⅱ)(4,4′-bipy)1.5(C8H4O4)(C8H5O4)(2)晶体属三斜晶系,P1空间群,a=1.06979(3)nm,b=1.09209(3)nm,c=1.47887(3)nm,α=91.795(2)°,β=93.2460(10)°,γ=118.6170(10)°,Z=2.通过使用不同的有机碱配体(2,2′-联吡啶和4,4′-联吡啶),并调节不同有机碱配体的用量,得到了结构不同的两个目标晶体产物相.产物均可稳定到3...  相似文献   
75.
高取代度玉米醋酸酯淀粉的制备与表征   总被引:3,自引:0,他引:3  
高取代度玉米醋酸酯淀粉的制备与表征;取代度;醋酸酯淀粉;玻璃化转变温度;结晶度  相似文献   
76.
迄今, 在中温水热条件下已合成了大量具有空旷骨架结构的过渡金属磷酸盐微孔材料[1], 这类材料在非线性光学材料、磁性材料、超导材料及催化等诸多方面具有潜在的应用前景[2~5].  相似文献   
77.
In the IBM4,when s.d.g bosons are presented,the symmetry group of the system is U(90) In this paper,the group chain.U90 U15(sdg)×U6(ST) SU15(sdg)×U6(ST) SU5(sdg)× O6(ST) SO5(dg)×O3(S)×O3(T) O3(dg)×O3(S)×O3(T) O3(J)×O3(T) is discussed,the reduction rules and the typical energy spectra are obtained.An example of a spectrum with this dynamical symmetry is found out,where the even-even nucleus 34S and odd-odd nucleus 34Cl are in one multiplet.  相似文献   
78.
The multicomponent coherent states associated with the Lie algebra SO(4) are presented. An inhomogeneous differential realization of SO(4) in this multicomponent coherent state space is obtained.  相似文献   
79.
基于磁二色效应的光发射电子显微镜磁成像技术是研究薄膜磁畴结构的一种重要研究手段,具有空间分辨率高、可实时成像以及对表面信息敏感等优点.以全固态深紫外激光(波长为177.3 nm;能量为7.0 eV)为激发光源的光发射电子显微技术相比于传统的光发射电子显微镜磁成像技术(以同步辐射光源或汞灯为激发源),摆脱了大型同步辐射光源的限制;同时又解决了当前阈激发研究中由于激发光源能量低难以实现光电子直接激发的技术难题,在实验室条件下实现了高分辨磁成像.本文首先对最新搭建的深紫外激光-光发射电子显微镜系统做了简单介绍.然后结合超高真空分子束外延薄膜沉积技术,成功实现了L10-FePt垂直磁各向异性薄膜的磁畴观测,其空间分辨率高达43.2 nm,与利用X射线作为激发源的光发射电子显微镜磁成像技术处于同一量级,为后续开展高分辨磁成像提供了便利.最后,重点介绍了在该磁成像技术方面取得的一些最新研究成果:通过引入Cr的纳米"台阶",成功设计出FePt的(001)与(111)双取向外延薄膜;并在"台阶"区域使用线偏振态深紫外激光观测到了磁线二色衬度,其强度为圆二色衬度的4.6倍.上述研究结果表明:深紫外激光-光发射电子显微镜磁成像技术在磁性薄膜/多层膜体系磁畴观测方面具备了出色的分辨能力,通过超高真空系统与分子束外延薄膜制备系统相连接,可以实现高质量单晶外延薄膜制备、超高真空原位传输和高分辨磁畴成像三位一体的功能,为未来磁性薄膜材料的研究提供了重要手段.  相似文献   
80.
Using the HPLC/DAD/ESI/MS method, the qualitative and quantitative analysis of senkyunolide A (SA) in the rhizomes of Ligusticum chuanxiong (Rhizoma chuanxiong; CX) and roots of Angelica sinensis (DG) was established. As a result, it was found that SA is a characteristic standard compound for the quality evaluation and chemical differentiation between CX and DG. Methanol was chosen in the preparation of standard solutions and extraction of samples based on the stability data. The identity of SA in CX and DG was unambiguously determined based on the quasimolecular ions in ESI-MS. A comprehensive validation of the method, including sensitivity, linearity, reproducibility and recovery, was conducted using the optimized chromatographic conditions. The linear calibration curve was acquired with R2>0.999 and limit of detection (S/N=3) was estimated to be 12.5 mug/g. The reproducibility was evaluated by repeated sample injection and replicated analysis of samples with the relative standard deviation (RSD) value found within 0.68%. The recovery rates of SA varied within the range of 96.91-101.50% with RSD less than 2.38%. In the present work, the contents of SA were quantified within 3.94-9.14 mg/g and 0.108-0.588 mg/g for 12 batches each of CX and DG. The results demonstrated that SA is a useful standard compound for the quality evaluation and chemical differentiation between CX and DG. The analytical procedure is precise and reproducible and thus suitable for the analysis of a large number of samples.  相似文献   
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