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991.
分子印迹电化学传感器敏感膜体系的构建及其研究进展 总被引:1,自引:0,他引:1
分子印迹技术具有构效预定性、特异识别性和广泛应用性的特点,在色谱分离、固相萃取、仿生传感器、模拟酶催化和膜分离等方面得到了广泛应用。近年来,分子印迹电化学传感器(MIECS)的研究日益受到人们的重视。在MIECS设计过程中,分子印迹敏感膜体系的构建非常关键,它直接影响着传感器的性能。该文简要介绍了MIECS的分类及其检测原理,对传统体系、自组装体系、分子印迹聚合物粒子镶嵌体系、电聚合体系和溶胶-凝胶体系等5种MIECS敏感膜体系的构建方法、特点及其研究进展进行综述,并展望了MIECS的发展方向。 相似文献
992.
合成了一个新颖的含ONN席夫碱配体N-水杨醛基-2-氨乙基苯并咪唑(HL),并在甲醇体系中合成了它的配合物ICu(L)(bipy)]ClO4(bipy为2,2'-联吡啶).利用X-射线单晶衍射法测定了配合物的晶体结构.配合物[Cu(L)(bipy)lClO4的晶体属于单斜晶系,C2/c空间群,a=2.585 5(8)nm,b=1.4355(5)nm,c=1.6242(5)nm,β=124.434(5)°,Z=8.在配合[Cu(L)(bipy)lClO4中,每个铜离子的配位数为5,分别和配体L的1个氧原子和2个氮原子及2,2'-联吡啶的2个氮原子配位,形成畸变的三角双锥配位环境.配合物[Cu(L)(bipy)]ClO4巾的氧键和π-π相互作用将配合物[Cu(L)(bipy)]ClO4连接成二维网络结构.用红外光谱、紫外-可见光谱对配合[Cu(L)(bipy)]ClO4进行了表征,并用循环伏安法对配合物进行了电化学性质的研究. 相似文献
993.
Switching on cell adhesion with microelectrodes 总被引:2,自引:0,他引:2
994.
《Analytical letters》2012,45(10):737-743
Abstract A procedure which combines electrochemical deposition and ESCA measurements for the determination of trace levels of metals in solution is described. The method is demonstrated by an experiment in which microgram quantities of Pb, Cd, and Bi are deposited on a mercury-coated platinum electrode and then detected by ESCA measurements. 相似文献
995.
Studies by the method of cyclic potential scanning from 0.2 to 1.9 V provided electroanalytical evidence that the reaction
of allyl dithiobenzoate with tetracyanoethylene (TCNE) in MeCN proceeds as the reaction of the TCNE.− radical anion with the PhSSAll.+ radical cation to form phenyl-substituted 2,2,3,3-tetracyano-7,8-dithiabicyclo[3.2.1]octane. When current is not applied,
the reaction does not proceed at 20°C for 3 days. However, this reaction in boiling MeCN occurs without electrochemical activation
and, apparently, involves intermediate formation of the above radical ions. It was established by semiempirical PM3 calculations
that allyl dithiobenzoate and TCNE form a stable charge-transfer complex that precedes chemical electron transfer.
Dedicated to the memory of Professor Viktor Nikolaevich Drozd.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 78–81, January, 1999. 相似文献
996.
997.
Lucía Rodríguez-Lpez Raquel Cela-Dablanca Avelino Núez-Delgado Esperanza lvarez-Rodríguez David Fernndez-Calvio Manuel Arias-Estvez 《Molecules (Basel, Switzerland)》2021,26(11)
In view of the rising relevance of emerging pollutants in the environment, this work studies the photodegradation of three antibiotics, evaluating the effects of the pH of the medium and the concentration of dissolved organic matter. Simulated light (with a spectrum similar to that of natural sunlight) was applied to the antibiotics Ciprofloxacin (Cip), Clarithromycin (Cla) and Trimethoprim (Tri), at three different pH, and in the presence of different concentrations of humic acids. The sensitivity to light followed the sequence: Cip > Cla > Tri, which was inverse for the half-life (Tri > Cla > Cip). As the pH increased, the half-life generally decreased, except for Cla. Regarding the kinetic constant k, in the case of Cip and Tri it increased with the rise of pH, while decreased for Cla. The results corresponding to total organic carbon (TOC) indicate that the complete mineralization of the antibiotics was not achieved. The effect of humic acids was not marked, slightly increasing the degradation of Cip, and slightly decreasing it for Tri, while no effect was detected for Cla. These results may be relevant in terms of understanding the evolution of these antibiotics, especially when they reach different environmental compartments and receive sunlight radiation. 相似文献
998.
Attachment of nickel nanoparticles on multiwalled carbon nanotubes (MWCNTs) was conducted to explore the influence of Ni loading
on the electrochemical capacitance of MWCNT electrodes. A chemical impregnation leaded to homogeneously disperse Ni particles
onto the surface of MWCNTs, and the Ni particles were found to be an average size of 30–50 nm. The capacitive behavior of
the MWCNT electrodes was investigated in 6 M KOH, by using cyclic voltammetry (CV), charge–discharge cycling, and ac electrochemical
impedance spectroscopy. CV measurements showed that the Faradaic current was found to increase with the Ni coverage, indicating
that the presence of Ni would enhance the pseudocapacitance through the redox process. Equivalent circuit analysis indicated
that both of electrical connection and charge transfer resistances accounted for the major proportion of the overall resistance
and were found to decrease with the amount of nickel. A linearity relationship between the total capacitance and the Ni population
reflected that each Ni particle exhibits an identical electrochemical activity in enhancing the electrochemical capacitance.
The overall electrochemical capacitance (including double layer capacitance and pseudocapacitance) of Ni-MWCNT electrode can
reach a maximum of 210 F/g over 500 cycles. 相似文献
999.
Tommasino L 《Radiation measurements》1999,31(1-6):395-400
Limited sensitivity and unpredictable background are the major drawbacks of damage track detectors in the assessment of low neutron doses and low concentrations of alpha emitters in biological and environmental samples. The simplest way to increase the sensitivity of the damage track detectors is to increase both the exposure time and the detector area. However, the strong variability of the background may make this task often impossible. This background problem has been finally solved by a new registration method based on counting coincidence spots in geometrically matched pair of detectors. By using spark counting and electrochemical etching, both of which produce spots visible at low magnification, coincidences induced in two matched detector-surfaces by a few-microns-long tracks can be easily seen. This novel counting approach can be considered just the converse of those used in the past with Bi-fission detectors and cosmic ray stacks. 相似文献
1000.
A. V. Toropchina V. V. Yanilkin V. I. Morozov L. P. Sysoeva A. I. Movchan B. I. Buzykin G. A. Chmutova 《Russian Journal of Electrochemistry》2003,39(11):1181-1196
Electron transfer processes in a series of pyrazole-2-in-5-ones (pyrazolones-5) and some of their thioanalogues are studied experimentally and theoretically for the first time. The electrochemical behavior of thiopyrazolones and oxygen analogues is found to differ. The effect the nature of the electrode, heteroatom, and substituents exerts on the redox potentials is established. Schemes of redox processes for the compounds studied in nonaqueous media are suggested. The schemes take account the ability of pyrazolones-5 to autoprotonation. Electrooxidation of 1-phenyl-3-methyl-4-benzoylpyrazole-2-in-5-one and its thioanalogues is shown to occur similarly to electroless oxidation with the formation of various dimers. It is established that, in the absence of active substituents during the electroreduction of compounds under study, the reaction center is the pyrazolone cycle, whose reduction does not involve decomposition of heterocyclic system. 相似文献