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1.
吴范宏  顾松  黄维垣 《有机化学》2006,26(5):671-675
以连二亚硫酸钠为引发剂, 烯丙基丙二酸二乙酯与多氟烷基碘代烷在温和反应条件下反应, 方便地得到一系列多氟烷基取代的环丙烷衍生物, 产率45%~55%. 在相同条件下, 烯丙基乙酰乙酸乙酯与多氟烷基碘代烷反应得到相应的加成物, 加成物随后用碱处理也得到环合的产物.  相似文献   
2.
Two silver(I) complexes of triethyl betaine (Et3N+CH2COO, Et3BET) have been prepared and characterized by X-ray crystallography. Both complexes, [Ag2(Et3BET)2 (NO3)2] (1) and [Ag2(Et3BET)2]n (ClO4)2n (2), contain centrosymmetric bis-carboxylato-bridged Ag2(carboxylato-O,O′)2 dimers (Ag---O = 2.16–2.23 Å). The dimeric unit in 1 is bound to a chelating nitrato group [Ag---O = 2.524(3), 2.619(3) Å] at each axial site, resulting in a discrete molecule. In 2 the dimers are extended into a stair-like cationic chain via the coordination of each metal centre by a carboxylato oxygen atom [Ag---O =2.565(5) Å] from an adjacent unit. The intra-dimer Ag… Ag distance is 2.928(1) Å for 1 and 2.856(2) Å for 2.  相似文献   
3.
Per- and poly-fluoroalkylated α, β-unsaturated alkenals were synthesized by the reaction of silyl enol ether of alkanals with per- and poly-fluoroalkyl iodide initiated by Na2S2O4 conveniently in high yield. Their corresponding alkenol and 2,4-dinitrophenylhydrazone were also synthesized.  相似文献   
4.
Using sulfinatodehalogenation and related reagent systems several groups of perfluoroalkylated compounds including olefins, dienes, phenolic compounds and aromatic dicarboxylic acids were synthesized which may be useful as potential monomers.  相似文献   
5.
前文已报道了全氟碘代烷在连二亚硫酸钠的引发下,对烯烃、富电子芳环的反应,并认为反应是自由基历程。本文报道应用这个反应合成α-全氟烷基吡咯。 Waksclman报道N-甲基吡咯与R_FI在自  相似文献   
6.
N, N-deithyl-iododifluoroacetamide 1 reacted with alkenes, alkynes in aqueous acetonitrile solutions of sodium dithionite and sodium hydrogen carbonate at room temperature to give the corresponding adducts, thus constituting a new method for introducing the CF2 group into organic molecules. Compound 1 reacted with conjugated olefins 2b, c to afford the iodine-free adducts 7b, c. The adducts 3d—f, from addition of 1 to alkenes 2d—f, could be converted into α,α-difluoro-γ-lactones 5d—f by treatment with silica gel. Compound 1 reacted with ethyl vinyl ether 2i to give aldehyde 8, and perfluoroalkyl or polyfluoroalkyl iodides reacted similarly. A radical mechanism was proposed for the addition reaction. Under the same condition, N,N-diethyl-bromodifluoroacetamide produced only the corresponding sulfinate Et2NC(O)CF2SO2Na.  相似文献   
7.
The lanthanide chelates of (l)-2, 2-dimethyl-6-trifluoromethyl-7-oxa-6, 8, 8, 9, 9, 10, 10, 10-octafluoro-3, 5-decanedione, Ln [(l)-CF3CF2CF2OCF (CF3) COCHCOC (CH3)3]3 (l-3a, Ln=Eu; 3b, Ln=Pr), are useful as 1H NMR shift reagents for direct determination of enantiomeric composition of enantiomorphous alcohols, ketones and amines. With these substrates, l-3a induces shift difference similar to that induced by Eu(facam)3 and Eu(hfbc)3. However, due to the higher solubility of the chelates l-3a and l-3b in nonpolar organic solvent such as CHCl3, CCl4 and only one 1H signal from l-3a and l-3b is observed, their application as the new chiral shift reagents seems promising. The spectral nonequivalence is also observed for dimethylsulfoxide in the presence of l-3a.  相似文献   
8.
Perfluoroalkyl-substituted tetrakisphenylporphyrins were synthesized through the couplingreaction of perfluoroalkyl iodides(R_FI)with the corresponding bromophenylporphyrin under theCu-bronze catalysis.  相似文献   
9.
Sodium perfluoroalkanesulfinates [Cl (CF2)n SO2 Na (1), a , n = 4; b , n = 6; c , n = 8] with the reduction potentials about 0.95—1.00V could be oxidized readily with various oxidizing agents such as Mn (OAc)3 2H2O, Ce (SO4)2, HgSO4 and Co2O3 to generate perfluoroalkyl radicals which added to the olefins RCH ? CHR' to give two kinds of adducts, namely RCH (Rf) CHXR' (3, X ? H; 4, X ? OAc), with good yields depending upon the solvent system used. Different oxidizing agents showed slight variation on the yields of the adducts. The reaction time could be greatly shortened at higher temperature. Thus, this reaction provides a new way for introducing a perfluoroalkyl group into olefinic compounds.  相似文献   
10.
基于内乘波概念的TBCC进气道过渡模态研究   总被引:2,自引:0,他引:2  
TBCC(涡轮基组合循环)在过渡模态的工作,是这种新型高速动力系统的关键问题。本文针对基于内乘波概念的内并联式TBCC进气道进行了其过渡模态流场的研究。首先,应用本团队自主提出的内乘波式进气道设计概念,提出一种新型TBCC进气道设计方案。然后,验证了其在设计马赫数4.0下实现全流量捕获,在模态转换时,分流板的分流是有效的。针对其在过渡模态马赫数2.5的性能,通过基于数值模拟的设计参数分析,发现在内参考收缩比为3.11时进气道流通面积合适可实现自起动、且综合性能较优。研究还发现,分流板偏转角度范围越小,分流段流动越好、通流出口总压恢复系数也越高。  相似文献   
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