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51.
赵丽杰 《石油化工高等学校学报》1997,10(1):11-13
阐述了以脂肪醇聚氧乙烯醚 ( AEO3)为起始剂 ,五氧化二磷为磷化剂 ,经直接酯化 ,水解制备脂肪醇聚氧乙烯醚磷酸酯。酯化反应:AEO3/P2 O5为 3.1 /1 ( mol/mol) ,温度为 60~70℃ ,时间为 6~ 7h;水解 :加水量为 4% ,温度为 60~ 70℃ ,时间为 2 h。酯化率大于 78% ;活性物质量分数大于 83% ;无机磷质量分数 <1 %。 相似文献
52.
迟永祥 《四川大学学报(工程科学版)》1997,(3)
本文介绍了一种先进的甘氨酸合成工艺,产品产率达85%,纯度大于98%,并采用正交设计优化实验方案。实验证明,本工艺与国内现行工艺相比,具有收率高,生产周期短,后处理简单等优点,有较高的工业价值 相似文献
53.
本文对TiO2-SO2-4型固体超强酸催化剂的制备进行了研究,并应用于苄基甲苯的合成。考察了H2SO4浓度,与H2SO4接触时间、焙烧温度等条件对催化剂活性的影响。通过改变催化剂用量、反应温度对产品收率的影响,由正交实验确定了最佳工艺条件。在最佳工艺条件下,对二元及三元复合型固体超强酸催化剂的活性也进行了一些研究。实验结果表明,TiO2-SO2-4型固体超强酸催化剂及其复合型催化剂可用于苄基甲苯的合成,具有工业摧广价值。 相似文献
54.
新型超高相对分子量阳离子聚丙烯酰胺的合成 总被引:8,自引:0,他引:8
研究了由过硫酸铵、甲醛次硫酸氢钠、功能性单体 DA及其它助剂组成的低温复合引发体系引发丙烯酰氧乙基三甲基氯化铵 (AETMAC)与丙烯酰胺 (AM)水溶液绝热聚合。考察了影响共聚物特性黏数[η]的因素 :单体浓度 1 8%~ 3 2 % ,引发剂浓度 (9~ 3 0 ) mg/L ,功能单体浓度 (2 .9~ 2 3 .2 )× 1 0 - 3mol/L。由该低温复合引发体系在适宜条件下引发 AETMAC/AM共聚合 ,可得到溶解性能很好、阳离子度为 1 0 %~70 % ,分子量 (1~ 2 )× 1 0 7的 P(AETMAC-AM)干粉。 相似文献
55.
相转移催化合成肉桂酸苄酯的研究 总被引:1,自引:0,他引:1
探索了以十六烷基三甲基溴化铵为相转移催化剂催化合成肉桂酸苄酯的方法,考察了催化剂、温度、时间和物料配比等因素对反应的影响。实验结果表明:十六烷基三甲基溴化铵是一种有效的催化剂,在最适宜的条件下,产率可达91.7%。最适宜的条件是:肉桂酸钠与氯化苄摩尔比为1:1.3,催化剂的质量为0.6g,反应时间3.0h,反应温度为95℃。产物的结构经IR,^1H NMR和MS表征。 相似文献
56.
57.
We have been developed novel catalysts for gasification of biomass with much higher energy efficiency than conventional methods (non-catalyst, dolomite, commercial steam reforming Ni catalyst). From the result of the gasification of cellulose over novel Rh/CeO2/SiO2 catalysts, it is found that the gasification process consists of the reforming of tar and the combustion of solid carbon. We also tested novel Rh/CeO2/SiO2 in the gasification with air, pyrogasification, and steam reforming of cedar wood. As a result, Rh/CeO2/SiO2 gave higher yield of syngas than the conventional steam reforming Ni catalyst. Furthermore, we compared the performance between single and dual bed reactors. Single bed reactor was effective in the gasification of cedar, however, it was not suitable for the gasification of rice straw since a rapid deactivation was observed. Gasification of rice straw, jute stick, baggase using the fluidized dual-bed reactor and Rh/CeO2/SiO2 was also investigated. Especially, the catalyst stability in the gasification of rice straw clearly was enhanced by using the fluidized dual bed reactor. 相似文献
58.
Assabumrungrat Suttichai Wongwattanasate Darin Pavarajarn Varong Praserthdam Piyasan Arpornwichanop Amornchai Goto Shigeo 《Korean Journal of Chemical Engineering》2004,21(6):1139-1146
The synthesis of ethyl tert-butyl ether (ETBE) from a liquid phase reaction between tert-butyl alcohol (TBA) and ethanol (EtOH)
in reactive distillation has been studied.β-Zeolite catalysts with three compositions (Si/Al ratio=13, 36 and 55) were compared by testing the reaction in a semi-batch
reactor. Although they showed almost the same performance, the one with Si/Al ratio of 55 was selected for the kinetic and
reactive distillation studies because it is commercially available and present in a ready-to-use form. The kinetic parameters
of the reaction determined by fitting parameters with the experimental results at temperature in the range of 343–363 K were
used in an ASPEN PLUS simulator. Experimental results of the reactive distillation at a standard condition were used to validate
a rigorous reactive distillation model of the ASPEN PLUS used in a simulation study. The effects of various operating parameters
such as condenser temperature, feed molar flow rate, reflux ratio, heat duty and mole ratio of H2O : EtOH on the reactive distillation performance were then investigated via simulation using the ASPEN PLUS program. The
results were compared between two reactive distillation columns: one packed withβ-zeolite and the other with conventional Amberlyst-15. It was found that the effect of various operating parameters for both
types of catalysts follows the same trend; however, the column packed withΒ-zeolite outperforms that with Amberlyst-15 catalyst due to the higher selectivity of the catalyst. 相似文献
59.
凉味剂左旋薄荷酰胺的合成 总被引:3,自引:0,他引:3
凉味剂WS 3 (即N 乙基 L 薄荷基甲酰胺 )可以左旋薄荷醇为原料 ,经氯代、羧酸化和酰胺化三步制成 ,以左旋薄荷醇为起始原料计 ,总产率为 3 0 .1 %。中间体 ( 1R ,2S ,5R) ( ) 氯代薄荷、( 1R ,2S ,5R) ( ) 薄荷基羧酸、( 1R ,2S ,5R) ( ) 薄荷基羧酸酰氯和终产品N 乙基 L 薄荷基甲酰胺通过GC、m .p.、旋光度的测定及红外光谱等分析确证其与目标产物结构一致。左旋的凉味剂WS 3凉味纯正强烈 ,无杂味。 相似文献
60.
Jinguang?Xu Zhijian?TianEmail author Junwei?Wang Yunpeng?Xu Zhusheng?Xu Liwu?Lin 《Korean Journal of Chemical Engineering》2003,20(2):217-221
Hydrothermal synthesis by using urea hydrolysis at 1.0-3.0 MPa and 120-130 ‡C was employed to prepare Mn-substituted hexaaluminate
catalysts for methane combustion. The results from DTA-MS demonstrated that CO3- and Off anions co-exist in the hydrothermal reaction. XRD reveals that the components of carbonates and hydroxides in the
hydrothermal reaction are more favorable than those in the (NH4)2CO3 co-precipitation for the formation of the Mn-substituted hexaaluminate phase. After calcination at 1,200 ‡C for 2 h, LaMnAl11O19 is the major phase of the catalyst prepared by the hydrothermal synthesis method while LaAlO3 is the major one of the catalysts prepared by NH4OH and (NH4)2CO3 co-precipitation. The catalyst prepared by hydrothermal synthesis has higher activity than that prepared by NH4OH and (NH4)2CO3 co-precipitation. The major reason is that more Mn2+ ions have incorporated into the hexaaluminate lattice. The effect of drying methods on the formation of hexaaluminate phase
was also discussed. 相似文献