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921.
Regiospecific N‐Arylation of Aliphatic Amines under Mild and Metal‐Free Reaction Conditions 下载免费PDF全文
Dr. Nibadita Purkait Gabriella Kervefors Erika Linde Prof. Berit Olofsson 《Angewandte Chemie (International ed. in English)》2018,57(35):11427-11431
A transition metal‐free N‐arylation of primary and secondary amines with diaryliodonium salts is presented. Both acyclic and cyclic amines are well tolerated, providing a large set of N‐alkyl anilines. The methodology is unprecedented among metal‐free methods in terms of amine scope, the ability to transfer both electron‐withdrawing and electron‐donating aryl groups, and efficient use of resources, as excess substrate or reagents are not required. 相似文献
922.
Alternative Strategies with Iodine: Fast Access to Previously Inaccessible Iodine(III) Compounds 下载免费PDF全文
《Angewandte Chemie (International ed. in English)》2018,57(27):8306-8309
Non‐iodinated arenes can be easily and selectively converted into (diacetoxyiodo)arenes in a single step under mild conditions by using iodine triacetates as reagents. The oxidative step is decoupled from the synthesis of hypervalent iodine(III) reagents, which can now be prepared conveniently in a one‐pot synthesis for subsequent reactions without prior purification. The chemistry of iodine triacetates was also expanded to heteroatom ligand exchanges to form novel inorganic hypervalent iodine compounds. 相似文献
923.
Congxin Xie Prof. Huamin Zhang Wenbin Xu Prof. Wei Wang Prof. Xianfeng Li 《Angewandte Chemie (International ed. in English)》2018,57(35):11171-11176
A zinc–iodine flow battery (ZIFB) with long cycle life, high energy, high power density, and self‐healing behavior is prepared. The long cycle life was achieved by employing a low‐cost porous polyolefin membrane and stable electrolytes. The pores in the membrane can be filled with a solution containing I3? that can react with zinc dendrite. Therefore, by consuming zinc dendrite, the battery can self‐recover from micro‐short‐circuiting resulting from overcharging. By using KI, ZnBr2, and KCl as electrolytes and a high ion‐conductivity porous membrane, a very high power density can be achieved. As a result, a ZIFB exhibits an energy efficiency (EE) of 82 % at 80 mA cm?2, which is 8 times higher than the currently reported ZIFBs. Furthermore, a stack with an output of 700 W was assembled and continuously run for more than 300 cycles. We believe this ZIFB can lead the way to development of new‐generation, high‐performance flow batteries. 相似文献
924.
Yusubov M. S. Zholobova G. A. Filimonova I. L. Vasil"eva V. P. Filimonov V. D. Chi Ki-Whan 《Russian Chemical Bulletin》2001,50(6):1051-1055
While heating 1,2,4,5-tetramethyl-3,6-bis(phenylethynyl)benzene, 1,3,5-trimethyl-2,4-bis(phenylethynyl)benzene, and 1,2,4,5-tetramethyl-3-(phenylethynyl)benzene with iodine in DMSO in the absence of oxygen, the triple bonds are oxidized to give the corresponding 1,2-diketones. In the presence of oxygen, the previously unknown competitive oxidative process causes the cleavage of the aryl—ethynyl bonds so that duroquinone and the corresponding 4-hydroxybenzils are formed. This cleavage is produced by oxygen only in the presence of iodine and DMSO. It was shown that the key stage of the process is the formation of intermediate charge-transfer complexes between polymethylbenzene rings and iodine. 相似文献
925.
The interaction of fullerene C60 with molecular iodine in organic solvents was studied. The stoichiometry of the complex formed, C60I2=13, was determined spectrophotometrically and by the interphase distribution technique. The constant of the formation of the adduct in toluene was calculated to be logK=8.9±0.3.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 481–483, March, 1995. 相似文献
926.
Francesco Minisci Francesco RecuperoCristian Gambarotti Carlo PuntaRoberto Paganelli 《Tetrahedron letters》2003,44(36):6919-6922
Alkylbenzenes are selectively functionalised to the corresponding acetates by nitric aerobic oxidation catalysed by N-hydroxyphthalimide and iodine. With cyclohexane the oxidation leads to a mixture of cyclohexyl acetate and trans-2-iodocyclohexyl acetate. The mechanism is discussed. 相似文献
927.
Sevim Hoyer 《Journal of fluorine chemistry》2004,125(6):989-996
The known compound phenyltetrafluoroiodine(V) is shown by X-ray diffraction to have a tetragonal pyramidal structure with an apical phenyl group. This structure is compared to that of IF(OTeF5)4, where the apical position is occupied by the fluorine atom. C6H5IF4 adds F−, forming C6H5IF5−, which has a pentagonal pyramidal structure with an apical phenyl group. Fluoride abstraction from C6H5IF4 by SbF5 results in the formation of the cation C6H5IF3+, which has a pseudotrigonal bipyramidal structure with the phenyl group occupying an equatorial position. Isoelectronic C6H5IOF2 has a similar structure, with the phenyl group and oxygen atom both occupying equatorial positions. 相似文献
928.
Laser-induced addition reactions of iodine with acetylene at 5145 and 4880 Å excitation wavelengths are studied, while trans-1,2-diiodoethylene is identified as the exclusive reaction product. A sequential addition reaction mechanism initiated by iodine atoms from the direct photodissociation process or collisional induced dissociation can be inferred. 相似文献
929.
Solutions of iodobenzene diacetate in CH3CN, AcOH, MeOH/H2O and MeOH (with or without base) were analyzed by electrospray ionization mass spectrometry (ESI-MS) and tandem mass spectrometry (ESI-MS/MS). The major species in CH3CN, AcOH and MeOH/H2O solutions are [PhI(OAc)2Na]+, [PhI(OAc)2K]+, [PhI]+, [PhIOAc]+, [PhIOH]+, [PhIO2Ac]+, [PhIO2H]+ and the dimer [Ph2I2O2Ac]+. On the other hand, MeOH solutions showed [PhIOMe]+ as the most abundant species. A similar result was observed adding 2, 3 or 4 equiv of KOH to MeOH solutions. However, in the presence of 10 equiv of KOH, probably occurs the formation of a polymeric material. Similarly, ESI-MS analysis of the MeOH solution of iodobenzene bis(trifluoroacetate) showed a pattern analogous to that observed for the corresponding solutions of PhI(OAc)2. However, ESI-MS spectral data of PhI(O2CCF3)2 of CH3CN suggests that the main species in solutions is iodosylbenzene, which contrasts with the results obtained for PhI(OAc)2. 相似文献
930.
报道了用4-硝基邻苯二甲酸制得四硝基酞菁镍再经Na_2S还原而得四氨基酞菁镍的合成方法以及产物的表征。四氨基酞菁镍与碘所得到的复合物〔Ni(NH_2)_4Pc〕I_x的碘含量范围很宽(0.4≤x≤3.77),其电导率为10~(-2)~10~(-3)S/cm,比未掺杂时提高了4~6个量级,而且在空气中很稳定,放置二个月后电导率仍几乎保持不变。 相似文献