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111.
Coordination complexes containing Ce(III) and tri-n-butyl phosphate (TBP) in the 1+, 2+ and 3+ charge states were generated using both direct infusion electrospray ionization (ESI) and fused droplet (FD) ESI using a target capillary, in which the analyte solutions are impinged by the ESI droplets. The same coordination complexes were produced in each experiment, and their relative abundances were also very close, suggesting that similar processes are occurring in both experiments. The ion species formed in both experiments have the general formula [Ce(NO(3) )(m=0-2) (TBP)(n=3-7) ]((3-m)+) . The appearance of abundant 1+ and 2+ ion pair complexes indicated that the ESI process was modifying the ion populations in the original solutions, which contain predominantly 3+ and 2+ species. The FD ESI experiments were less sensitive for coordination complexes compared to direct infusion ESI; however, mid-picomolar quantities of coordination complexes were measured using the target capillary, indicating that sensitivity would be sufficient for measuring species in many industrial separations processes. 相似文献
112.
113.
Jia Liu Chao Ding Sicheng Gong Kun Fu Huiping Deng Jun Shi 《Molecules (Basel, Switzerland)》2022,27(20)
The nonradical process in the peroxydisulfate (PDS) oxidation system is a promising method for antibiotic removal in water. In this study, CuO@CNT was successfully synthesized by a facile approach to catalyze PDS. The removal efficiency of the antibiotic sulfamethoxazole (SMX) was 90.6% in 50 min, and the stoichiometric efficiency (ΔSMX/ΔPDS) was 0.402. The very different degradation efficiency of common organic contaminants revealed the selective oxidation of the surveyed system. The process of 1O2 oxidation and the electron-transfer regime was exhibited by chemical quenching tests, electron paramagnetic resonance (EPR) determination, a UV–vis spectrophotometer, X-ray photoelectron spectroscopy (XPS) detection, and cyclic voltammetry (CV) measurements. Sustainable catalysis was promoted by the circulation between the surface electron-rich centers of Cu(II) and Cu(III). Dissolved oxygen (DO) and a metastable Cu(III) intermediate contributed to the generation of 1O2. Still, a portion of SMX was removed by the mildly activated PDS. Moreover, the influence factors (pH, dosage, water matrix) were examined, and suppressions were acceptable by common anions and real water. Distinguished from the radical process, unique intermediate products were ascertained via the theoretical calculation and liquid chromatography–mass spectrometry (LC-MS) detection. Furthermore, CuO@CNT showed a satisfactory activation ability in the cycling experiments. Overall, this study developed CNT to be a supporter of CuO, unveiled the mechanism of catalysis, and evaluated the application potential of the nonradical process. 相似文献
114.
氮气分子具有高的化学惰性,氮气的活化与转化充满挑战.含氮有机物在国民经济发展中具有广泛且重要的价值,实现温和条件下由氮气直接转化为含氮有机物在科学和经济上均具有重要意义.目前对氮气的活化与转化的研究主要集中在主族与过渡金属配合物,稀土和锕系元素由于具有特殊的电子结构,在氮气的活化与转化领域展现出了区别于主族和过渡金属的特殊反应活性.我国作为稀土和钍资源大国,开展稀土及锕系元素的固氮转化研究具有重要的战略意义.本综述归纳和总结了过去五年内稀土和锕系金属氮气配合物的合成,以及由稀土和锕系配合物促进的以氮气为原料生成含氮有机物的研究. 相似文献
115.
基于5-(3,4-二羧基苯氧基)间苯二甲酸(H4dppa)配体,通过水热法设计并合成了2种镧系金属有机骨架(Ln-MOFs):{(dima)[Dy (dppa)(H2O)2]·2.5H2O}n(Dy-MOF)和{(dima)[Eu (dppa)(H2O)2]·1.5H2O}n(Eu-MOF)(dima=二甲胺阳离子)。并用元素分析、红外光谱、单晶X射线衍射等对其进行了结构表征。2种Ln-MOFs为异质同构的二维网状结构,相邻的二维网络通过氢键作用进一步形成三维超分子网络结构。荧光分析表明Dy-MOF和Eu-MOF在室温下具有优良的荧光性能,而且Dy-MOF还具有优异的荧光传感性能,可高效、高灵敏检测多种水中污染物:苯胺(ANI)、硝基苯(NB)、四环素(TC)、嘧霉胺(PTH)以及色氨酸(Trp)。此外还探究了Dy-MOF检测污染物时的荧光淬灭机理。 相似文献
116.
合成了4个新的基于多胺酚配体的Dy(Ⅲ)和Zn/Ni-Dy(Ⅲ)配合物:[Dy(CH_3OCH3)L](1),[Dy2(μ-H2O)L2](2),[Zn2DyL2]ClO4·H2O(3)和[Ni2DyL2]ClO4·H2O (4)(H3L=N,N′,N″-三(3,5-二甲基-2-羟基苯酚)-1,4,7-三氮杂环壬烷)。X射线单晶衍射分析表明,配合物1和2分别为单核和双核Dy(Ⅲ)配合物,3和4为M-Dy(Ⅲ)-M三核配合物(M=Zn (3),Ni (4))。磁性测试表明,配合物1和2具有场诱导的慢磁弛豫行为,且2具有多个磁弛豫过程,配合物3和4中没有观察到明显的慢磁弛豫行为。荧光测试表明,配合物1~3具有Dy(Ⅲ)离子典型的窄带特征发射,由于Ni(Ⅱ)离子的荧光猝灭作用,配合物4没有明显的荧光产生。 相似文献
117.
通过水热方法合成了一种新颖的异金属金属-异烟酸无机-有机杂化体[Zn0.5(H2O)]{(Hg2Cl5)[Er(C6NO2H4)3(H2O)2]}(HgCl2)·0.5CH3OH·0.5H2O (1)并对其进行了单晶X-射线衍射结构表征。该化合物是首例4f-3d-5d多金属-异烟酸配合物。化合物1属于单斜晶系C2/c空间群,每个单胞中有8个分子,晶体学参数为:a = 34.165(4) Å,b = 9.4692(8) Å,c = 24.575(3) Å,β = 115.090(5)°,V = 7200(1) Å3,C18.50H21Cl7ErHg3N3O10Zn0.50,Mr = 1495.25,Dc = 2.759 g/cm3,T = 293(2) K,μ(MoKα) = 15.954 mm-1,F(000) = 5400, R1/wR2 = 0.0561/0.0909,共有6468个独立衍射点,其中[I > 2σ(I)]的有3157个。该化合物具有新颖的二维{(Hg2Cl5)[Er(C6NO2H4)3(H2O)2]}层状结构,由Hg2Cl5–连接[Er(C6NO2H4)3(H2O)2]链形成。该二维层和氯化汞及结晶水之间通过氢键形成三维结构,甲醇分子和水合锌离子位于该三维结构的空隙中。对化合物1的磁性测试显示该化合物具有反铁磁作用。 相似文献
118.
Patrycja Wytrych Jzef Utko Julia Kak Maciej Ptak Mariusz Stefanski Tadeusz Lis Jolanta Ejfler ukasz John 《Molecules (Basel, Switzerland)》2022,27(1)
In alkali metal and lanthanide coordination chemistry, triphenylsiloxides seem to be unduly underappreciated ligands. This is as surprising as that such substituents play a crucial role, among others, in stabilizing rare oxidation states of lanthanide ions, taking a part of intramolecular and molecular interactions stabilizing metal-oxygen cores and many others. This paper reports the synthesis and characterization of new lithium [Li4(OSiPh3)4(THF)2] (1), and sodium [Na4(OSiPh3)4] (2) species, which were later used in obtaining novel gadolinium [Gd(OSiPh3)3(THF)3]·THF (3), and erbium [Er(OSiPh3)3(THF)3]·THF (4) configuration, it can result in res were determined for all 1–4 compounds, and in addition, IR, Raman, absorption spectroscopy studies were conducted for 3 and 4 lanthanide compounds. Furthermore, direct current (dc) variable-temperature magnetic susceptibility measurements on polycrystalline samples of 3 and 4 were carried out in the temperature range 1.8–300 K. The 3 shows behavior characteristics for the paramagnetism of the Gd3+ ion. In contrast, the magnetic properties of 4 are dominated by the crystal field effect on the Er3+ ion, masking the magnetic interaction between magnetic centers of neighboring molecules. 相似文献
119.
以1,1′-二羟基-5,5′-联四唑(H_2BTO)为配体,镧系金属离子作为金属中心,采用溶剂热法制备了5种金属配合物:[La_2(BTO)_3(H_2O)_8]·2H_2O (1)、[Ce_2(BTO)_3(H_2O)_8]·2H_2O (2)、[Pr_2(BTO)_3(H_2O)_8]·2H_2O (3)、[Sm_2(BTO)_3(H_2O)_8]·2H_2O (4)和[Nd_2(BTO)_3(DMF)_4]·6H_2O (5)。通过单晶X射线衍射和元素分析对5种配合物的结构进行了表征。结果表明,5种配合物均属于单斜晶系,P2_1/n空间群。利用差示扫描量热法研究了配合物1~4的热稳定性,采用Kissinger法和Ozawa法分别计算了其热分解动力学参数。 相似文献
120.
[5‐(p‐alkoxy)phenyl‐10, 15, 20‐tri‐phenyl] porphyrin and their rare earth complex liquid crystalline
Miao Yu Wen‐yang Zhang Yong Fan Wen‐ping Jian Guo‐fa Liu 《Journal of Physical Organic Chemistry》2007,20(4):229-235
Three series of porphyrin liquid crystalline compounds, [5‐(p‐alkoxy)phenyl‐10, 15, 20‐tri‐phenyl] porphyrin and their rare earth complexes (Tb (III), Dy (III), Er (III), Yb (III)), with a hexagonal columnar discotic columnar(Colh) phase have been synthesized. These compounds were characterized by elemental analysis, molar conductances, UV‐visible spectra, infrared spectra, luminescence spectra, and cyclic voltammetry. These compounds exhibit more than one mesophases, which transition points of temperature change from ?33.6 to 16.0 °C, and transition points of temperature for isotropic liquid also increase from 4.9 to 38.2 °C, with increasing chain length. Their surface photovoltage (SPV) response have also been investigated by the means of surface photovoltage spectroscopy (SPS) and field‐induced surface photovoltage spectroscopy (EFISPS). It was found that their SPV bands are analogous with the UV‐visible absorption spectra and derived from the same transition. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献