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1.
用2,4,6-吡啶三甲酸和稀土钐、镝或钆的高氯酸盐溶液、碳酸锶、碳酸钾在180℃水热条件下进行反应,制备出3个含有3种金属离子的配位聚合物[LnSrK(ptc)2(H2O)]n(Ln=Sm(1)、Dy(2)、Gd(3),H3ptc=2,4,6-吡啶三甲酸)。X射线单晶衍射分析表明三者具有相同的结构,属三斜晶系,P1空间群。配合物中配体2,4,6-吡啶三甲酸根以2种不同的配位方式与3种金属离子配位,一种方式中连接了7个金属离子,另一种方式中连接了8个金属离子。Ln(Ⅲ)为八配位,与羧基上的6个氧原子和2个吡啶环上的2个氮原子配位;Sr(Ⅱ)也是八配位,配位原子均为氧原子;K(I)与5个氧原子配位。荧光发射光谱表明,钐和镝的配合物在紫外光激发下均发射Sm(Ⅲ)和Dy(Ⅲ)两种离子的特征荧光,钆的配合物在紫外光激发下由于发生荷移跃迁而发射绿色荧光。 相似文献
2.
Ming-Wei Hong Li Song Yi Zhao Lai-Shun Qin Cong-Yong Wang Hong-Sheng Shi Jia-Yu Guo Xiao-Dong Tao Kang-Ying Shu Wen-Xiang Chai 《Journal of Cluster Science》2014,25(6):1627-1640
A series of strongly phosphorescent copper(I) halide complexes, namely [Cu(μ-X)POP]2 (X = Cl (1), Br (2), I (3), Br0.5Cl0.5 (4), POP = bis[2-(diphenylphosphino)phenyl]ether), have been synthesized by reacting CuX with the diphosphine ligand in 1:1 molar ratio. All complexes were characterized by spectroscopic analysis (IR, UV–Vis), elemental analysis, and photoluminescence study. Single-crystal X-ray diffraction revealed that complex 2 is a dinuclear structure which is constructed by two μ-X bridges and two POP ligands as μ2 bridges. Other complexes were determined as isologues of complex 2 by powder X-ray diffraction and elemental analysis. All complexes exhibit intense blue-green phosphorescence with a lifetime of ~1 μs in the solid state. The halogen-mixed complex presents a lightly change in the luminescence comparing to that of parent complexes. The excited states of all complexes have been assigned as halide-to-ligand charge transfer state mixed metal-to-ligand charge transfer character based on the time-dependent density functional theory calculations. All complexes are thermally stable according to thermogravimetric analysis so that they are suitable for applying in luminescent devices. 相似文献
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用NaOH溶液吸收法研究了ZnNiZSM-5芳构化催化剂的积炭量,用色谱纯二氧化碳考察了此方法的准确度.用热失重法确定了烧炭的最佳温度为570℃,根据实验确定了烧炭时间为7h,空气流量为120mL/min.采用正交实验设计法对影响芳构化催化剂积炭量的温度、空速、高径比进行了研究.通过实验结果可知,积炭量最少的最佳工艺条件是温度为560℃,空速为1. 5h-1,高径比为6.1. 相似文献
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对回收聚对苯二甲酸乙二酯(R-PET)/LLDPE-g-MA马来酸酐改性的线性低密度聚乙烯共混物进行不同条件的热处理, 采用差示扫描量热仪(DSC)研究共混物基体PET的玻璃化转变行为. 结果表明, 当热处理温度低于PET的玻璃化转变温度(Tg)时, PET的玻璃化转变区域出现热焓松弛现象. 随着热处理温度的增加, PET的Tg逐渐升高; 在50~70 ℃下热处理48 h后, PET的Tg逐渐稳定. 当热处理温度高于PET的Tg而低于100 ℃时, PET的玻璃化转变区域出现2个热流转变, FTIR分析表明, PET分子构象开始发生变化. 当热处理温度为100 ℃时, DSC曲线上PET的玻璃化转变消失, PET的结晶度明显增加, 说明PET开始冷结晶的温度在90~100 ℃之间. 相似文献
7.
本文以聚(苯乙烯-异丙烯膦酸)-磷酸氢锆(ZPS-IPPA)为载体,对该载体进行氯甲基化、胺化修饰后与手性Salen Mn(Ⅲ)轴向配位,合成了一种新的固载型手性Salen Mn(Ⅲ)催化剂,采用FTIR,DR UV-Vis,XPS,SEM,TEM,TG等手段对催化剂进行表征.以次氯酸钠和间氯过氧苯甲酸为氧化剂,考察了固载催化剂对a-甲基苯乙烯不对称环氧化反应的催化性能,结果表明,固载型催化剂的催化活性比相应均相催化剂略低,但对映体选择性明显提高.在NaClO/PPNO氧化剂体系中0 ℃反应24h,a-甲基苯乙烯环氧化物的转化率达68%,e.e.值达99%.循环使用8次后催化效果无明显降低. 相似文献
8.
A series of triblock copolymers,containing a CO2-switchable block poly(2-(dimethylamino)ethyl methacrylate) (PDM) block and two symmetrical hydrophilic blocks polyacrylamide (PAM),were synthesized using atom transfer radical polymerization (ATRP) method.The pH and conductivity tests showed that the triblock copolymer exhibited switchable responsiveness to CO2,i.e.a relatively low conductivity of solution could be switched on and off by bubbling and removing of CO2,and the triblock copolymer aqueous solution displayed a CO2-switchable viscosity variation.The changes were all attributed to protonation of tertiary amine groups in PDM blocks and proven by 1H-NMR.Cryogenic transmission electron microscopy and dynamic light scattering characterization demonstrated that the viscosity variation was the result of a unilamellar vesicle-network aggregate structure transition.The release of rhodamine B from the vesicles with and without CO2 stimuli showed the potential application in drug delivery domains;after CO2 bubbling,the drug release rate could be accelerated.Finally,reasonable mechanism of CO2-switchable morphology changes and CO2-induced drug release was proposed. 相似文献
9.
合成了螺[异苯并呋喃-1(3H),9'-(9H)-2'-N,N-二苄胺基-6'-二乙胺基占吨]-酮-3,C_(37)H_(34)N_2O_3,单斜晶系,空间群Cc,晶体学参数为a=16.826(4),b=10.648(4),c=17.618(7),β=92.25(2)°,V=3154(2),Z=4,M_r=566.7,D_x=1.19g/cm3,F(000)=1200。结构由直接法解出,偏离因子R=0.080。分子由占吨和异苯并呋喃两部分组成Y形结构,占吨部分相连的苄基的两个苯环位于占吨部分的两侧。 相似文献
10.
Two- and three-dimensional lanthanide complexes: synthesis, crystal structures, and properties 总被引:1,自引:0,他引:1
Xia J Zhao B Wang HS Shi W Ma Y Song HB Cheng P Liao DZ Yan SP 《Inorganic chemistry》2007,46(9):3450-3458
3,5-pyrazoledicarboxylic acid (H3L) reacts with nitrate salts of lanthanide(III) (Ln=Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, and Er) under hydrothermal conditions to form a series of lanthanide polymers 1-9. These nine polymers have the same crystal system of monoclinic, but they exhibit three different kinds of metal-organic framework structures. The complexes {[Ln2(HL)3(H2O)4].2H2O}n (Ln=Pr (1), Nd (2), and Sm (3)) were isostructural and exhibited porous 3D frameworks with a Cc space group. The complexes {[Ln2(HL)3(H2O)3].3H2O}n (Ln=Eu (4), Gd (5), and Tb (6)) were isostructural and built 2D double-decker (2DD) frameworks with a P21/c space group. The complexes {[Ln(HL)(H2L)(H2O)2]}n ((Ln=Dy (7), Ho (8), and Er (9)) were also isostructural and formed 2D monolayer (2DM) frameworks with a P21/n space group. The structure variation from the 3D porous framework to the 2D double-decker to the 2D monolayer is attributed to the lanthanide contraction effect. Notably, six new coordination modes of 3,5-pyrazoledicarboxylic acid were observed, which proved that 3,5-pyrazoledicarboxylic acid may be used as an effective bridging ligand to assemble lanthanide-based coordination polymers. The photophysical and magnetic properties have also been investigated. 相似文献