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61.
Wenbo Liu Dr. Peichen Tang Yi Zheng Dr. Yun-Lai Ren Xinzhe Tian Wankai An Prof. Xianfu Zheng Yinggang Guo Zhenpeng Shen 《化学:亚洲杂志》2021,16(21):3509-3513
Nitrogen transfer from cyanide anion to an aldehyde is emerging as a promising method for the synthesis of aromatic nitriles. However, this method still suffers from a disadvantage that a use of stoichiometric Cu(II) or Cu(I) salts is required to enable the reaction. As we report herein, we overcame this drawback and developed a catalytic method for nitrogen transfer from cyanide anion to an alcohol via the complete cleavage of the C≡N triple bond using phen/Cu2O as the catalyst. The present condition allowed a series of benzyl alcohols to be smoothly converted into aromatic nitriles in moderate to high yields. In addition, the present method could be extended to the conversion of cinnamic alcohol to 3-phenylacrylonitrile. 相似文献
62.
《印度化学会志》2021,98(12):100224
Fertilization is the set of operations that consists of fertilizing the soil so that the plant finds all these mineral nutrition needs, among these nutrients is found potassium nitrate (KNO3), as an important source of two elements which are nitrogen (N) and potassium (K). The need for potassium nitrate for plants will increase dramatically as its demand for nutrition growing up. However, the application of this potassium in fertilization is limited by a physicochemical parameter which is solubility. The availability of potassium and nitrogen in ionic form, which can be assimilated by the plant, is closely related to its solubility in irrigation water. Herein, we have chosen three experimental parameters such as the KNO3 content, the magnetization time, and the type of water, to optimize the factors which have the maximum effect on KNO3 solubility.We adopted a model from nine experiments performed with Minitab software, which informed us that the solubility of KNO3 in irrigation water is strongly influenced by water type, magnetization time and KNO3 content. The best conditions which allow the best solubility of potassium nitrate are 24% KNO3, 30 min of water magnetization, and salt water (SW). 相似文献
63.
Johannes Kretsch Anne-Kathrin Kreyenschmidt Timo Schillmöller Dr. Märt Lõkov Dr. Regine Herbst-Irmer Prof. Dr. Ivo Leito Prof. Dr. Dietmar Stalke 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(38):9858-9865
A novel sterically demanding bis(4-benzhydryl-benzoxazol-2-yl)methane ligand 6 (4−BzhH2BoxCH2) was gained in a straightforward six-step synthesis. Starting from this ligand monomeric [M(4-BzhH2BoxCH)] (M=Na ( 7 ), K ( 81 )) and dimeric [{M(4-BzhH2BoxCH)}2] (M=K ( 82 ), Rb ( 9 ), Cs ( 10 )) alkali metal complexes were synthesised by deprotonation. Abstraction of the potassium ion of 8 by reaction with 18-crown-6 resulted in the solvent separated ion pair [{(THF)2K@(18-crown-6)}{bis(4-benzhydryl-benzoxazol-2-yl)methanide}] ( 11 ), including the energetically favoured monoanionic (E,E)-(4-BzhH2BoxCH) ligand. Further reaction of 4−BzhH2BoxCH2 with three equivalents KH and two equivalents 18-crown-6 yielded polymeric [{(THF)2K@(18-crown-6)}{K@(18-crown-6)K(4-BzhBoxCH)}]n (n→∞) ( 12 ) containing a trianionic ligand. The neutral ligand and herein reported alkali complexes were characterised by single X-ray analyses identifying the latter as a promising precursor for low-valent main group complexes. 相似文献
64.
利用和频光谱技术详细研究了磷酸钾缓冲溶液与带负电荷的生物仿生膜(d54-DMPG磷脂双层膜)相互作用的实时过程.通过监控CD2、CD3、磷脂分子头部的磷酸根以及羰基官能团的光谱信号随加入磷酸钾缓冲溶液的实时变化,获得了磷脂双层膜分子结构的动力学变化.结果表明K+能够结合到细胞膜上,并且很快地引起了CD2、CD3、磷脂头部磷酸根以及羰基官能团信号的变化.根据各官能团的和频信号响应,磷酸钾缓冲溶液很可能是通过在双层膜中形成环形气孔来与磷脂双层膜发生作用.该结果可以很好地解释磷酸钾缓冲溶液环境下的离子协助蛋白质的跨膜过程. 相似文献
65.
Facile Preparation of α‐Zirconium Phosphate/Polyaniline Hybrid Film for Detecting Potassium Ion in a Wide Linear Range 下载免费PDF全文
Yanhong Wang Chunfeng Xue Xiumin Li Xiao Du Zhongde Wang Guozhang Ma Xiaogang Hao 《Electroanalysis》2014,26(2):416-423
A novel α‐zirconium phosphate/polyaniline (α‐ZrP/PANI) hybrid film used as K+ ion sensor was fabricated on carbon paper by electrochemical method. Mechanisms of film formation and detection of K+ ions were also proposed. The exfoliated α‐ZrP was mixed with PANI and deposited on carbon paper. The resultant α‐ZrP/PANI film exhibited a good current response to K+ ion with different concentrations. It also showed a wide logarithmic linear response in detecting K+ ions in the ranges of 10?8–10?4 M and 10?4–10?2 M, respectively. The results can be attributed to the synergetic effect of α‐ZrP and PANI. 相似文献
66.
An efficient synthesis of Biginelli-type compounds using potassium phthalimide as a green, mild, and commercially available organocatalyst in a one-pot, multi-component cyclocondensation reaction of cyclopentanone, aldehydes, and urea/thiourea is reported. The present methodology is a green approach to access 4-aryl-7-(aryImethylene)-3,4,6,7-tetrahydro-1H-cyclopenta[d]pyrimidin-2(5H)-ones/thiones. It offers several merits such as simple operational procedures, no use of hazardous organic solvents, and cheap and environmentally friendly solid basic catalyst. 相似文献
67.
原位漫反射傅里叶变换红外光谱研究锰铁基催化剂上低温选择性催化还原反应机理简 总被引:4,自引:0,他引:4
采用自蔓延燃烧法制备了Ti0.9Mn0.05Fe0.05O2-δ催化剂,运用原位漫反射傅里叶变换红外光谱对该催化剂的NO和NH3稳态吸附以及NO和NH3瞬态反应进行了详细地分析与讨论. 结果表明,相比于Lewis酸性位,150℃时Brönsted酸性位吸附的NH3更具有SCR活性;与双齿硝酸盐和桥式硝酸盐相比,NO吸附产生的单齿硝酸盐是主要的中间物种;该SCR反应遵循Eley-Rideal和Langmuir-Hinshelwood机理,但以后者为主. 另外,O2的存在有利于NO的氧化和配位态NH3的活化. 相似文献
68.
69.
Litao Zhao Fanghong Luo Anting Wang Jing Zhang Yuanhang Wang Liangtao Zhao Zhaoyan Wang Qiaosheng Pu 《Electrophoresis》2020,41(15):1273-1279
Mutations in the potassium channel genes may be linked to the development of epilepsy and affect the blood potassium levels. Therefore, accurate determination of potassium in the blood will be critical to diagnose the cause of epilepsy. CE is a competent technique for the fast detection of multiple ions, but complicated matrices of a blood sample may cause significant variation of migration times and the peak shape. In this work, a procedure for rapid stabilization of the capillary inner surface through preflushing of a blood sample was employed. The process takes only 40 min for a capillary and then it can be used for more than 2 weeks. No pretreatment of the blood sample or other surface modification of the capillary is needed for the analysis. The RSDs of the migration time and peak area were reduced to 1.5 and 5.1% from 12.6 and 14.5%, respectively. The proposed method has been successfully applied to the determination of the potassium contents in the blood sample of patients with epilepsy at different stages. The recoveries of potassium ions in these blood samples are in a range from 86.5 to 104.5%. 相似文献
70.
The separation of the principal inorganic anions (bromide, carbonate, chlorate, chloride, fluoride, nitrate, nitrite, sulfate, phosphate) has been achieved using a capillary electrophoresis system with indirect UV detection at 260 nm. Several types of cationic surfactants (quaternary ammonium, phosphonium or methonium) were tested as electroosmotic flow modifiers and added to a chromatebased buffer prepared from potassium dichromate. The influence of many physicochemical parameters such as nature and concentration of cationic surfactant, buffer pH, dichromate concentration buffer, voltage and temperature upon the migration time of an analyte anion, peak efficiency, asymmetry factor, and finally resolution has been investigated. A linear relationship between the corrected area and the anion concentration in the 2.5–50 ppm range was obtained, thus allowing the quantitative analysis of anions in mineral water. Finally, by increasing the hydrodynamic injection time, the separation of inorganic anions at a low concentration level of 50 ng/ml was achieved without any loss of resolution. 相似文献