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排序方式: 共有318条查询结果,搜索用时 31 毫秒
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以废弃生物质油茶壳为原料,在经过一系列炭化、磺化后成功制备了一种新型的炭基固体酸催化剂(C-SO3H),考察了催化剂制备过程中温度和浓度等因素对催化活性的影响,利用X射线衍射仪、扫描电子显微镜、红外光谱仪和核磁共振波谱仪等对催化剂及其催化废弃聚对苯二甲酸乙二醇酯(PET)的催化效率、催化机理等进行了测定和分析。结果表明,催化剂的最佳制备条件为:浸渍比1∶1、浸渍浓度2 mol/L、炭化温度700 ℃、磺化温度160 ℃;催化PET的最大的转化率和BHET回收率分别为95 %和68 %;催化剂微观呈现无定型炭结构,含有大量的羟基,具有较大的比表面积;醇解反应产物为单体BHET。 相似文献
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In this study, the two most effective aromatic amine antioxidants N,N′-diphenyl-1,4-phenylenediamine (DPPD) and N-phenyl-1,4-phenylenediamine (NPPD), were used at a concentration of 2000 ppm. The impact of antioxidants on the oxidation stability, exhaust emission and engine performance of a multi-cylinder diesel engine fuelled with MB20 (20% Moringa oil methyl ester and 80% diesel fuel blend) were analysed at varying speed conditions at an interval of 500 rpm and a constant load. It was observed that, blending with diesel enhanced the oxidation stability of the moringa biodiesel by approximately 6.97 h, and the addition of DPPD and NPPD to MB20 increased the oxidation stability up to 34.5 and 18.4 h, respectively. The results also showed that the DPPD- and NPPD-treated blends reduced the NOx emission by 7.4% and 3.04%, respectively, compared to the untreated blend. However, they do have higher carbon monoxide (CO) and hydrocarbon (HC) levels and smoke opacities, but it should be noted that these emissions are still well below the diesel fuel emission level. The results show that the addition of antioxidant with MB20 also improves the engine's performance characteristics. Based on this study, MB20 blends with amine antioxidants can be used in diesel engines without any modification. 相似文献
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K. Thirugnanasambandham 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(3):343-350
The present research analyzes the extraction of oil from Moringa oleifera Lam. seed using ultrasound-assisted extraction (UAE) technique under different operating conditions such as temperature, solvent type, and time. Three factors with three levels Box-Behnken response surface design was employed to optimize and investigate the effect of process variables on the response (oil yield). The independent variables showed significant effect on the extraction process. Interactive effects of the extraction process variables were analyzed by Pareto analysis of variance (ANOVA), and second-order polynomial model was used to plot the 3D response surface plot. Optimum extraction conditions for the maximizing the extraction yield of oil (59%) was found to be: temperature of 35°C, solvent type of 2, and time of 20 min. FT-IR was used to analysis the oil. From the results, it can be concluded that the UAE is the effective technique to extract the oil from Moringa oleifera Lam. seed. 相似文献
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Beibei Zhao Hua Li Tao Lan Di Wu Zhicheng Chen 《Journal of the American Oil Chemists' Society》2019,96(5):523-533
This work focused on physicochemical property assaying, fatty acid composition, triacylglycerol (TAG) profiles, and unsaponifiable matter composition of the Chinese Moringa oleifera seed oil. The results indicated that there was no significant difference in approximate nutritional components between M. oleifera seeds from China and India, while variations in the mineral element contents are significant. Both the Soxhlet extraction method and the aqueous enzymatic extraction method were adopted to extract oil from Chinese M. oleifera seeds. Oil yield obtained using the Soxhlet extraction method was higher than that obtained using the aqueous enzymatic extraction method. While both the iodine value and unsaponifiable matter content of the aqueous enzymatic extracted oil were a little higher than that of the Soxhlet extracted oil. Both oils possess a very low acid value and peroxide value, suggesting their good quality as edible oil. Fatty acid composition results indicated that this oil was especially high in oleic acid. Characterization of the TAG composition was achieved by a two-dimensional high-performance liquid chromatography (HPLC) coupling of nonaqueous reverse-phase and silver ion HPLC with the atmospheric pressure chemical ionization mass spectrometry method. A total of 22 TAG including 16 regioisomers were determined. Composition results of unsaponifiable matters revealed that this oil possesses a number of phytosterols, in which β-sitosterol and stigmasterol are most predominant. 相似文献
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Ming Chang Jie Lian Ruijie Liu Qingzhe Jin Xingguo Wang 《International Journal of Food Science & Technology》2014,49(7):1715-1721
Camellia oleifera meal was evaluated to be a potential feedstock for the production of yellow wine (YW), and process conditions were investigated. In this study, C. oleifera meal was firstly pretreated using mixed cultured Bacillus subtilis and Aspergillus niger under solid‐substrate fermentation to degrade the tea saponin (TS) for the following YW fermentation. Response surface methodology helped evaluate the effects of the selected operating parameters, and the optimal condition at a fixed time of 4 days, which gave a 67.84 ± 0.23% degradation rate of TS, was reached as inoculum concentration of 16%, initial moisture content of 55% and temperature of 30 °C. Finally, 7‐day fermentation was harvested to be the most suitable pretreatment for producing YW from C. oleifera meal, and the twice‐feeding fermentation for YW was obtained as wheat koji 12% and active yeast 1.2%. In addition, ample amino acids, phenolic components and the trace TS endowed the C. oleifera wine, the more nutritional characteristics. 相似文献
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《The International journal of environmental studies》2013,70(6):617-618
The present study involved the use of a pilot scale water treatment plant to treat turbid surface water from a stream using processed Moringa oleifera seed and alum as primary coagulants. At low initial turbidity of 21.5 to 49.3 NTU, residual turbidities of 2.7, 1.8 and 1.4 NTU were achieved after treatment using Moringa oleifera, alum, and alum with Moringa oleifera as coagulant‐aid, respectively. For medium turbidities varying from 51.8 to 114 NTU, lowest residual turbidities of 2.9, 1.2 and 1.4 were achieved after treatment using Moringa oleifera, alum, and alum with Moringa oleifera as coagulant‐aid, respectively. For high turbidity varying from 163 to 494 NTU, minimum residuals of 1.4, 1.9 and 0.9 NTU were achieved after treatment using Moringa oleifera, alum, and alum with Moringa oleifera as coagulant‐aid, respectively. The proposed mechanism for turbidity removal by Moringa oleifera seed in this study is a combination of partial‐charge neutralization and micro‐bridging or an electrostatic patch mechanism based on the results of zeta potential measurements. 相似文献
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研究恭城油茶对D-半乳糖致衰老小鼠认知障碍的改善作用。将KM小鼠随机分为正常组、衰老模型组、Vc干预组(100 mg/kg)、恭城油茶干预组(750 mg/kg)。Morris水迷宫实验评价小鼠学习记忆能力;检测各组小鼠海马体和脑指数;比色法测定海马体、脑和肠道组织中谷胱甘肽过氧化物酶(GSH-Px)和总超氧化物歧化酶(T-SOD)活性、总抗氧化能力(T-AOC)和丙二醛(MDA)水平;取部分海马体和脑组织制备切片,观察其病理变化。结果发现,恭城油茶能显著升高衰老小鼠海马体指数(35.56%)和脑指数(42.16%)(P<0.05);增加平台象限游泳时间比例(20.44%)和平台象限游泳路程比例(16.10%)(P<0.05);提高海马体中GSH-Px(37.95%)、T-SOD(86.83%)、T-AOC活性(199.22%)(P<0.05),降低MDA含量(65.66%)(P<0.05);增加脑组织中GSH-Px(331.49%)和T-SOD活性(177.16%)(P<0.05);切片结果显示,恭城油茶可缓解衰老过程中脑部的损伤。综上,恭城油茶可通过减... 相似文献