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61.
以苄基氯(1a)、4-氯苄基氯(1b)、特戊酸氯甲酯(1c)为原料,通过叠氮取代和1,3-偶极环加成反应合成了三种含羟基的三氮唑衍生物1-苄基-4-羟甲基-1H-1,2,3-三氮唑(3a)、1-(4-氯-苄基)-4-羟甲基-1 H-1,2,3-三氮唑(3 b)、1-(特戊酸甲酯基)-4-羟甲基-1 H-1,2,3-三氮唑(3 c),实验应用FT-IR、1HNMR、13CNMR对产物的结构进行了表征,结果证实了合成路线的可行性,目标产物的收率分别为85.32%、90.26%、72.62%。 相似文献
62.
Sammy Drissi‐Amraoui Thibault E. Schmid Jimmy Lauberteaux Christophe Crvisy Olivier Basl Renata Marcia deFigueiredo Stphanie Halbert Hlne Grard Marc Mauduit Jean‐Marc Campagne 《Advanced Synthesis \u0026amp; Catalysis》2016,358(15):2519-2540
An efficient copper‐catalyzed enantioselective conjugate addition of dimethylzinc to unsaturated 2‐acyl‐N‐methylimidazoles has been achieved using a chiral bidentate hydroxyalkyl‐NHC ligand. The reactions proceed with excellent regioselectivity (1,4 vs. 1,6 and 1,8) in extended conjugated systems to afford the 1,4‐adducts in high enantioselectivities. This regioselectivity could be ascertained by DFT studies highlighting the crucial role of the imidazole ring. Thanks to the development of efficient protocols to regenerate the unsaturated 2‐acyl‐N‐methylimidazole moiety, an iterative process has been developed ultimately leading to 3,5,7 all‐syn or anti‐anti polydeoxypropionate stereodiads.
63.
Liang Wei Zuo‐Fei Wang Lu Yao Guofu Qiu Haiyan Tao Hua Li Chun‐Jiang Wang 《Advanced Synthesis \u0026amp; Catalysis》2016,358(24):3955-3959
An unprecedented copper(II)‐catalyzed enantioselective 1,3‐dipolar [3+4] cycloaddition of azomethine imines with in situ formed azoalkenes has been realized. This strategy provides a facile access to biologically important 1,2,4,5‐tetrazepine derivatives in high yield with exclusive regioselectivity and high stereoselectivity. Moreover, enantioenriched azomethine imines could be obtained via an efficient kinetic resolution using the same approach.
64.
The blend properties of semi-crystalline and amorphous polycaprolactone (PCL) are shown here for the first time. The amorphous polycaprolactone (PCLB) having 20% branches was made by radical-ring-opening polymerization of 2-methylene-1,3-dioxepane. The presence of branches led to non-crystallinity in PCLB. The blends were made in solution in entire concentration range and showed some very interesting properties in terms of synergistic effect on crystallinity leading to the increased crystallinity of PCL and induced crystallinity of amorphous PCLB, minima in the % elongation and maxima in spherulite size depending upon the ratio of amorphous and crystalline part. There was a drastic increase in the compostability as compared to pure PCL on adding even low % of amorphous PCLB in the blends without affecting the thermal stability. The addition of PCLB also affected the transparency and it increased exponentially from about 8% at 650 nm for PCL to about 45% for a blend with composition PCL:PCLB 30:70. 相似文献
65.
以2,3-O-异丙亚基-D-甘油醛为原料合成抗肿瘤药物中间体3R-2,2-二氟-3-羟基-3-(2,2-二甲基-1,3-二氧戊环基)戊酸乙酯,在锌粉的催化下加入了三甲基氯硅烷使需要得到的R结构产物的比例提高,反应温度为45℃,反应时间3h,收率为72.1%以上。用IR与1HNMR对其结构进行了表征。 相似文献
66.
以乙酰苯胺、间苯二胺为主要原料,经磺酰化、酰胺化、脱乙酰基,合成了替代致癌染料中间体N,N'-1,3-苯基二-(4-氨基)苯磺酰胺,并优化了酰胺化反应条件。产物分别经元素分析、红外、质谱和核磁表征确证了结构。 相似文献
67.
通过单因素试验筛选出DMF作为3-氯-2-氯甲基丙烯(CCMP)碱性水解制备2-亚甲基-1,3-丙二醇(MEPO)的溶剂.水解产物采用GC-MS联用仪、GC-900气相色谱仪进行结构分析,确定CCMP水解最佳工艺条件为:转速700 r/min,w(NaOH)=10%,温度92℃,V(CCMP)∶V(NaOH)=1∶5,m(DMF)∶m(CCMP)=0.2,反应时间6 h,在此条件下CCMP的水解率可达95%. 相似文献
68.
Frank S
S Rogerson Zelia Azevedo Nlia Fortunato Victor A
P de Freitas 《Journal of the science of food and agriculture》2002,82(11):1287-1292
1,3‐Dimethoxybenzene was identified by GC–O, GC–MS and Kovats indices (polar Supelcowax, 1709; non‐polar Rtx‐5MS, 1158) as a new volatile component of port wine. Sensory evaluation described this compound as having a sweet medicinal odour with hazelnut, resinous and woody notes. Respective threshold limits in model wine and port wine were 21 and 47 µg l?1. Quantitative analysis by GC–MS, using a selected characteristic ion (m/z 138), indicated that young port wines from the 1998 vintage contained up to 3 µg l?1 whereas ports from the 1999 vintage contained up to 20 µg l?1. © 2002 Society of Chemical Industry 相似文献
69.
Marko R. Djokic Kevin M. Van Geem Carlo Cavallotti Alessio Frassoldati Eliseo Ranzi Guy B. Marin 《Combustion and Flame》2014
The importance of 1,3-cyclopentadiene (CPD) and cyclopentadienyl (CPDyl) moieties in the growth of polycyclic aromatic hydrocarbons (PAHs) was studied using new experimental data and ab initio calculations. The experimental investigation was performed in a tubular continuous flow pyrolysis reactor under both high (24molN2/molCPD) and low (5molN2/molCPD) nitrogen dilutions, covering a temperature range of 873–1123 K, at a fixed pressure of 1.7 bara. At the most severe conditions up to 84% of CPD is converted, and the amount of PAHs is more than 65 wt%. Major products observed during CPD pyrolysis were benzene, indene, methyl-indenes and naphthalene, in line with previous studies. On-line GC × GC-FID/(TOF-MS) also allowed to quantify minor species (methane, toluene, styrene, phenanthrene, anthracene, etc.), never reported before at this level of accuracy. The new experimental data have been used to further analyze the role of the successive interactions of CPD, indene, and naphthalene as well as the recombination and addition reactions of their resonantly stabilized radicals and refine their kinetics. The results of the modeling study are in good agreement with existing and new experimental observations. 相似文献
70.
Catalytic use of zeolites in the Prins reaction of arylalkenes 总被引:1,自引:0,他引:1
María A. Aramendía Victoriano Borau César Jiménez José M. Marinas Francisco J. Romero Francisco J. Urbano 《Catalysis Letters》2001,73(2-4):203-206
The Prins reaction of various arylalkenes with paraformaldehyde on different zeolites as solid acid catalysts was studied. The main product of the reaction under the experimental conditions used was found to be the corresponding 1,3-dioxane. Of the catalysts tested, beta (75) zeolite proved the most active and selective in the Prins reaction of styrene, with a selectivity of 41.4% and a conversion of 95%. Other zeolites such as USY and, especially, ZSM-5, provided much lower yields. The reactions of other arylalkenes were found to be strongly influenced by the substituents on the double bond. 相似文献