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71.
Fluorogenic benzothiazole-based receptor has been easily immobilised onto filter paper and silica nanoparticle by sol-gel reaction. The sensing ability of the benzothiazole-immobilised thin layer filter paper chromatography (TLC-1) was evaluated on the basis of fluorescent changes caused by metal ions that were dropped onto the TLC plate. The TLC-1 exhibited a high affinity and selectivity for Hg2+ over other competing metal ions. Therefore, the TLC-1 holds promise as a portable sensor for the detection of Hg2+ in aqueous solution. Furthermore, the adsorption capacity of a column packed with SiO2-1 was evaluated by the application of metal ions under various experimental conditions, such as pH, flow rate and concentration. The SiO2-1 column removed 98% of Hg2+ from drinking water containing 10 ppb of Hg2+. The adsorption capacity of the SiO2-1 column was not strongly affected by pH and flow rates. 相似文献
72.
The First Polyiodo Complex – Triethylsulfoniumtriiodomercurate(II)-tris(diiodine), (Et3S)[Hg2I6]1/2 · 3 I2 After Raman spectroscopic investigation of the system HgI2/Et3SIx, x = 3, 5, 7, triethylsulfoniumtriiodomercuratetris(diiodine), (Et3S)[Hg2I6]1/2 · 3 I2 was synthesized by reacting of HgI2 and liquid Et3SI7. The compound crystallizes at room temperature triclinically in the space group P1 with a = 879.4(7), b = 1 209.1(5), c = 1 291.5(5) pm, α = 96.16(3)°, β = 103.82(6)°, γ = 99.05(5)° and Z = 2. The crystal structure is composed of disordered Et3S+ cations, the centrosymmetric complex anion [HgI2/2I2]22? and three connecting iodine molecules I2. 相似文献
73.
Manual Snchez-Maestre Rafael Rodríguez-Amaro Eulogia Muoz Juan Jos Ruiz Luis Camacho 《Journal of Electroanalytical Chemistry》1995,390(1-2)
The reduction of 4,4′-bipyridine (BPH2+2) on mercury in an acid medium gives a very narrow sharp tail-less reversible voltammetric peak that can be ascribed to the formation of a two-dimensional (2D) phase of the cation radical BPH·+2 at the electrode according to the reaction The corresponding oxidation peak possesses similar properties and arises from the destruction (fusion) of the 2D phase.In this work we studied the influence of some experimental variables, namely the type of anion present in the medium, the concentration of 4,4′-bipyridine and temperature on the 2D phase transition peaks. Also, we tested various analytical criteria to validate this assignation and fitted both voltammetric peaks numerically to the theoretical model developed for this purpose. 相似文献
BPH2+2 + e− |BPH·+2|2D
74.
Cheng X Li S Jia H Zhong A Zhong C Feng J Qin J Li Z 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(6):1691-1699
A new series of intramolecular-charge-transfer (ICT) molecules (compounds 1, 2, and 3) were synthesized by attaching various electron-donating thiophenes groups to a triphenylamine backbone with an aldehyde group as the electron acceptor. Based on the protection reaction between ethanethiol and aldehyde, the corresponding dithioacetals (compounds S1, S2, and S3) were prepared to serve as novel colorimetric and fluorescent chemosensors for Hg(2+) ions. Also, compound S1 was further utilized to construct the chemical-reaction-based conjugated polymer probe (PS1) towards Hg(2+) ions. In the presence of as little as 10 nM Hg(2+), compound PS1 displayed an apparent change in the fluorescent intensity. The sensing processes were revealed to be mediated by ICT, as confirmed by time-dependent DFT calculations. Furthermore, compound S1 was successfully applied to microscopic imaging for the detection of Hg(2+) in HeLa cells with ratiometric fluorescent methods. 相似文献
75.
Dr. Tania Lasanta Prof. Dr. José M. López‐de‐Luzuriaga Dr. Miguel Monge Dr. M. Elena Olmos David Pascual 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(15):4754-4766
Heteronuclear complexes {[Hg(R)2][Au(R′)(PMe3)]2}n (R=R′=C6Cl2F3 ( 3 ); R=R′=C6F5 ( 4 ); R=C6Cl2F3, R′=C6F5 ( 5 ); R=C6F5, R′=C6Cl2F3 ( 6 )) were prepared by the treatment of the corresponding organomercury compounds, [Hg(C6X5)2], with two equivalents of [Au(C6X5)(PMe3)]. Their crystal structures, as determined by using X‐ray diffraction methods, display Au???Hg interactions. Although only compound 4 and 5 show luminescence in the solid state, all of these compounds quench the fluorescence of naphthalene in solution. Solution studies of these derivatives suggest a cooperative effect of the gold(I) center in switching on the quenching capabilities of the [Hg(C6X5)2] synthon with naphthalene. Theoretical studies confirmed the quenching ability of the organomercury species in the presence of gold. 相似文献
76.
Harry J. Whitlow Margaretha Andersson Mikael Hult Leif Persson Mohamed El Bouanani Mikael Östling Carina Zaring Nils Lundberg David D. Cohen Nick Dytlewski Peter N. Johnston Ian F. Bubb Scott R. Walker Erik Johanson Sture Hogmark P. Anders Ingemarsson 《Mikrochimica acta》1995,120(1-4):171-181
Recoil Spectrometry covers a group of techniques that are very similar to the well known Rutherford backscattering Spectrometry technique, but with the important difference that one measures the recoiling target atom rather than the projectile ion. This makes it possible to determine both the identity of the recoil and its depth of origin from its energy and velocity, using a suitable detector system. The incident ion is typically high-energy (30–100MeV)35C1,81Br or127I. Low concentrations of light elements such as C, O and N can be profiled in a heavy matrix such as Fe or GaAs. Here we present an overview of mass and energy dispersive recoil Spectrometry and illustrate its successful use in some typical applications. 相似文献
77.
本文采用不同的溶剂对溶解前后的胆色素类结石进行了超微结构的观测.并用能谱仪对溶解前后的胆色素类结石进行了主要元素的检测,同时对特征色素类结石进行了有机元素分析.通过比较溶解前后超微结构和各种元素含量的变化,认为胆红素与金属离子,尤其是钙及其它二价金属离子,形成了胆色素盐或配位给合物,并与糖蛋白等螯合成了大分子复合物,这是胆色素类结石难溶的主要原因. 相似文献
78.
倒数示波计时电位法在合金样品测定中的应用 总被引:2,自引:0,他引:2
应用倒数示波计时电位法,在含有吸附络合物的溶液中,采用桂汞电极作为极化电极,测定了Cu^2+、Ni^2+、Cd^2+、Pb^2+等几种金属离子的检测下限,并通过沿(dE/dt)-1 ̄E曲线上的峰高对合金样品进行定量分析,得到满意结果。实现了示波分析由常量到微量的飞跃。 相似文献
79.
碳纤维汞膜微电极1.5次微分伏安法测定米托蒽醌的研究 总被引:4,自引:1,他引:4
米托蒽醌(MXT)能吸附在碳纤维汞膜微电极表面,阴极溶出时,产生一个灵敏的1.5次微分溶出峰,其峰电流和米托葱酿的浓度在1.0×10-5mol/L~1.3×10-9mol/L范围内具有良好的线性关系,经3min的富集,检出限可达1.0×10-10mol/L,据此建立了测定MXT的灵敏的新方法,本文讨论了实验条件,并对血样中的MXT进行了测定。 相似文献
80.