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11.
《Analytical letters》2012,45(12):2237-2250
Abstract An ultrasensitive electrochemical immunoassay based on biocatalytic deposition has been proposed for the detection of Schistosoma japonicum antibody (SjAb) in infected rabbit serum. Schistosoma japonicum antigen (SjAg) was immobilized on the gold electrode surface via glutaraldehyde crosslink and then incubated with infected rabbit serum containing SjAb; finally, the goat anti-rabbit IgG labeled with alkaline phosphatase was sandwiched to form the immunocomplex on the gold electrode surface. The alkaline phosphatase converted nonelectroactive substrate into the reducing agent and the latter, in turn, reduced metal ions to form electroactive metallic product on the electrode surface. Linear sweep voltammetry (LSV) was used to quantify the amount of the deposited silver and give the analytical signal for SjAb. Assay conditions such as the antigen concentration and enzymatic silver deposition time were optimized. The electrochemical immunosensor was able to realize a reliable determination of SjAb in the dilution range from 1:5000 to 1:100 with a detection limit of 1:6457 of dilution ratio. The feasibility of the proposed immunosensor for possible clinical applications was also investigated by analyzing real serum samples. 相似文献
12.
The synthesis and crystal structure of γ‐aminobutyric acid naphthalene diimides derivative with the LaIII coordination complex, [La(L)(DMF)Cl]n, was reported, which is a twofold interpenetrating metal‐organic framework architecture. The coordination polymer was characterized by elemental analysis, infrared spectroscopy, thermal gravimetric analysis, and single‐crystal X‐ray diffraction. The optical properties of the crystallized complex were investigated both in solution and the solid state. 相似文献
13.
Alex R. Petrov Noa K. Pruß Andrei V. Churakov Konstantin A. Rufanov Jrg Sundermeyer 《无机化学与普通化学杂志》2019,645(9):679-682
A convenient one‐pot synthetic protocol towards THF and DME solvates of lanthanum and other early lanthanide tribromides was developed using the water‐catalyzed reaction of lanthanide(III) oxides with highly reactive Me3SiBr in situ formed from commercially available disilane Si2Me6 and Br2. This practical route allows to obtain the target lanthanum tribromide solvates [LaBr3(thf)4] ( 1a ) and [LaBr3(dme)2]2 ( 1b ) as well as analogous early lanthanide molecular tribromide solvates [NdBr3(thf)4] ( 2a ), [NdBr3(dme)2] ( 2b ), [SmBr3(thf)2] ( 3a ), and [SmBr3(dme)2] ( 3b ) difficult to prepare by other solution‐based procedures. The molecular structure of 1b· 2CH2Cl2 was determined by an XRD study. 相似文献
14.
Jonas Strh Laura Ruiz Arana Philipp Polzin Irma Vania Eliani Patric Lindenberg Niclas Heidenreich Csar dos Santos Cunha Sebastian Leubner Huayna Terraschke 《无机化学与普通化学杂志》2019,645(5):537-543
Despite the strong technological importance of lanthanide complexes, their formation processes are rarely investigated. This work is dedicated to determining the influence of synthesis parameters on the formation of [Ce(bipy)2(NO3)3] as well as Ce3+‐ and Tb3+‐substituted [La(bipy)2(NO3)3] (bipy = 2,2′‐bipyridine) complexes. To this end, we performed in situ luminescence measurements, synchrotron‐based X‐ray diffraction (XRD) analysis, infrared spectroscopy (IR), and measured pH value and/or ion conductivity during their synthesis process under real reaction conditions. For the [Ce(bipy)2(NO3)3] complex, the in situ luminescence measurements initially presented a broad emission band at 490 nm, assigned to the 5d→4f Ce3+ ions within the ethanolic solvation shell. Upon the addition of bipy, a red shift to 700 nm was observed. This shift was attributed to the changes in the environment of the Ce3+ ions, indicating their desolvation and incorporation into the [Ce(bipy)2(NO3)3] complex. The induction time was reduced from 8 to 3.5 min, by increasing the reactant concentration by threefold. In contrast, [La(bipy)2(NO3)3] crystallized within days instead of minutes, unless influenced by high Ce3+ and Tb3+ concentrations. Monitoring and controlling the influence of the reaction parameters on the structure of emissive complexes is important for the development of rational synthesis approaches and optimization of their structure‐related properties like luminescence. 相似文献
15.
LI Ben-xian LIU Xiao-yang CHU Qing-xin LI Guang-hua WANG Xiao-feng ZHAO Xu-dong 《高等学校化学研究》2013,29(5):825-827
High pressure synthesis of solid material tends to increase the density,coordination number,symmetry of material and shorten bond length.The solid synthesized at a high pressure and decompressed to ambient pressure often exhibits a metastable "stretched" state,within the high pressure stability field.The crystal grown at a high pressure is of great importance with the development of high pressure technology.Crystal growth is an important factor in the material synthesis.And many methods including gas,solid and solution methods have been used to obtain various single crystals[1].Especially,flux method is an important method for crystal growth,where the components of the desired substance dissolved in a solvent(flux) grow in the process of deposit.Its advantage is that the crystal growth displays natural facets and the disadvantage is that the crystals are relatively small.Up to date,some solid materials have been successfully synthesized by high pressure flux method[2-7]. 相似文献
16.
Zhang Youjin Hu Qixiu Guan Hangmin Hu Biao Fang Zhiyong Cheng Tao Zhang Zude 《化学物理学报(中文版)》2005,18(5):827-831
Single-crystalline LaF3 flakes was synthesized through a facile solution-phase approach in aqueous ammonia and ethylenediamine. Applying the thermal treatment at 100 ℃ for 20 h, the LaF3 recrystallized, grew epitaxially and precipitated into flakes in aqueous ammonia or ethylenediamine. The formation of flakes could be attributed to the coordination effect of the solvent. 相似文献
17.
耐高温高表面氧化铝的制备及性质──添加钡及钡与镧的协同作用对氧化铝热稳定性的影响 总被引:7,自引:0,他引:7
氧化铝是高温催化反应中常用的载体材料. 高于1 000 ℃时, Al2O3通过表面活性原子的迁移和表面羟基脱水发生烧结, 并向α相转变[1,2], 同时随着比表面积剧烈下降, 导致催化剂活性组分聚集, 催化剂活性下降等. 大量研究表明, 稀土元素, 硅及碱土元素可明显改善氧化铝的热稳定性[3~8]. 本文以溶胶-凝胶法单独引入Ba元素, 考察了Ba添加量对Al2O3热稳定性的影响. 还采用溶胶-凝胶与表面浸渍相结合的方式共同引入La和Ba, 考察了两元素协同作用对Al2O3热稳定性的影响. 相似文献
18.
19.
Min Ren Aili Wang Chen Ge Chunyan Liu Longbao Yu Tingshun Jiang Yumin Liu Ying Hang 《Applied Surface Science》2008,254(22):7314-7320
TiO2-coated sericite powders were prepared by the chemical deposition method starting from lamellar sericite and TiCl4 in the presence or absence of La3+ cations. After calcination at 900 °C for 1 h, the resultant TiO2 nanoparticles on the sericite surfaces existed in anatase phase. The light scattering indexes of the TiO2-coated lamellar sericite powders were dozens of times higher than that of the naked lamellar sericite powders. The presence of La3+ in the deposition solution was beneficial to the formation of the small-sized anatase TiO2 nanoparticles, resulting in the formation of the dense and uniform island-like TiO2 coating layers in a large range of the weight ratios of TiO2 to sericite from 5% to 20%. The TiO2-coated lamellar sericite powders prepared in the presence of La3+ had higher light scattering index than that prepared in the absence of La3+. XPS analysis shows that when La3+ cations were absent in the reaction solution, TiO2 coating layers anchored at the sericite surface via the Ti-O-Si and Ti-O-Al bonds. The presence of La3+ cations caused the formation of Si-O-La and Al-O-La bonds at the sericite surface and Ti-O-La bond at the surface of TiO2 coating layers. After coating TiO2 on the sericite surface, the yellowness of the TiO2-coated sericite powders obviously increased and the brightness slightly decreased. 相似文献
20.
The yet unknown intermetallic phase La5Al3Ni2 was obtained by partially crystallizing amorphous La50Al25Ni25 at 550 K (further heating above 600 K leads to irreversible disappearance of this phase), and its crystal structure was determined from X‐ray powder diffraction data. The crystal structure of the La5Al3Ni2 phase constitutes a new structure type (Cmcm, a = 14.231Å, b = 6.914Å, c = 10.460Å, oC40) and is built from [Al3Ni2] chains surrounded by La atoms. In the ternary system La‐Al‐Ni La5Al3Ni2 is located on the section La50Al50−nNin (0 ≤ n ≤ 50) with the binary compounds LaAl and LaNi as end members. Strikingly, also the crystal structures of the end members can be conceived as chain structures with Al and Ni chains surrounded by La, respectively. 相似文献