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91.
以黄瓜为例 ,研究了其切割后经臭氧、涂膜、低温等处理后的物理、生理变化 .结果表明 ,黄瓜经过 4 .2mg/m3质量浓度的臭氧水以及涂膜配方C处理后具有较好的保鲜效果 ,能抑制最小加工黄瓜的呼吸作用 ,阻止可溶性固形物的分解 ,以及营养成分的损失 ,并有效地抑制酶促褐变 .  相似文献   
92.
前途光明的臭氧漂白技术   总被引:2,自引:1,他引:2  
本文介绍了臭氧漂白的漂白原理、发展过程及世界臭氧漂白的最新发展,展望了臭氧漂白的光明前景.  相似文献   
93.
臭氧和山梨酸钾对台湾青枣贮藏研究   总被引:6,自引:0,他引:6  
臭氧是一种强氧化剂,具有广谱、高效的杀菌作用,能降解乙烯、乙醇等有害气体,较常用于果蔬上的保鲜。台湾青枣(ZizyphusmauritianaLam.)经臭氧和山梨酸钾处理后在常温下贮藏保鲜,结果表明处理2用3×10-6的臭氧处理后,台湾青枣果实的贮藏有较好的效果。试验结果显示提高了好果率,第6天处理2有一个峰值为15.34CO2mg/kg·h,呼吸强度高峰比其他处理低;延缓了果实硬度,减缓了Vc含量的下降,提高了超氧化物歧化酶的活性。  相似文献   
94.
介绍3种新型橡胶防护蜡XJL系列产品的开发及其应用性能。结果表明:在轿车子午线轮胎胎侧胶中加入新型橡胶防护蜡,硫化胶的物理性能变化不大,耐臭氧老化性能明显提高;当新型橡胶防护蜡用量为2份时,胶料成本较低和产品外观质量较好;10#和30#橡胶防护蜡的耐臭氧老化性能优于或相当于国内外同类产品。  相似文献   
95.
AO/MBR/臭氧氧化工艺处理制衣废水   总被引:1,自引:0,他引:1  
史超  杨合  周玉  郭海霞 《广州化工》2013,(22):140-141,159
对天津某制衣厂废水处理系统存在的水量和水质等问题进行调研分析,在充分利用原有处理构筑物和设备,同时利用厂区周围空地的前提下,采用AO/MBR/臭氧催化氧化工艺进行扩容和升级。工程运行结果表明,改造工艺经调试运行稳定,处理出水BOD5、SS、色度等达到《城市污水再生利用城市杂用水水质》(GB/T18920-2002)标准。  相似文献   
96.
Abstract: Durum wheat grain from the field is naturally contaminated with bacteria, yeast, and mold. The reduction in aerobic plate count (APC) and yeast and mold count (YMC) is often necessary before processing wheat. Gaseous ozone, ozonated water, and acetic acid solution are nontraditional antimicrobial agents for grains and are safe for humans and the environment. Better disinfection may be possible by applying antimicrobial agents to grain in a fluidized state. Fluidization increases the exposure of grain surfaces, resulting in uniform and quick contact of grain with antimicrobial agents. Therefore, a fluidized bed was developed with automated spraying system (to spray treatment waters), and a port for gaseous ozone injection. The pressures and velocities within the fluidized bed system were measured to characterize the system. The treatments used on fluidized grain were: distilled water (control), gaseous ozone (6 ppm), ozonated water (23 mg/L), gaseous ozone + ozonated water (6 ppm, 23 mg/L), acetic acid solution (0.5%), acetic acid + ozonated water (0.5%, 26 mg/L), and gaseous ozone + acetic acid + ozonated water (6 ppm, 0.5%, 26 mg/L). The last of these treatments was most effective with 1.7 and 3.3 log reduction in APC and YMC, respectively. This combined treatment can be used to replace the chlorinated water that industry uses during tempering of grain. Ozonated water alone resulted in a 0.3 log reduction in both APC and YMC. Gaseous ozone alone did not cause a significant reduction in APC and YMC.  相似文献   
97.
BACKGROUND: Recent studies indicate that chemical oxidation may be compatible with subsequent biodegradation in contaminated soils. To test this, soil contaminated with 2,4‐dinintrotoluene (2,4‐DNT) was treated in batch slurry reactors with (1) ozone, (2) modified Fenton chemistry (MFC), and (3) iron‐activated sodium persulfate (SPS). Chemical and subsequent biological oxidation were monitored, and compared with biodegradation alone. Release of nitrite and nitrate distinguished biological from chemical oxidation of 2,4‐DNT, respectively. DNT‐degrading microorganisms were enumerated. The disappearance of volatile fatty acids (VFAs) accumulated during chemical oxidation was also monitored. RESULTS: In the biological reactor 66% of the 2,4‐DNT was degraded, but further biodegradation was inhibited by nitrite concentrations approaching 18 mmol L?1. At the doses tested, all oxidants achieved chemical oxidation followed by biodegradation, resulting in 98% DNT removal overall. Ozone achieved the greatest DNT removal (70%), but also caused the greatest reduction in DNT degraders and the longest rebound time (60 days) before biodegradation of the remaining DNT and VFAs. SPS resulted in the least DNT removal by chemical oxidation (37%), but showed no obvious rebound period for DNT degraders, and even signs of co‐existing chemical and biological oxidation. By releasing nitrate, which is less toxic than nitrite, the oxidants kept nitrite levels below 18 mmol L?1, enabling the follow‐on biodegradation step to attain lower concentrations of 2,4‐DNT than biodegradation alone. CONCLUSIONS: All three chemical oxidants were compatible with biodegradation of residual 2,4‐DNT. Post‐oxidation bioremediation should be included in remedial designs. Copyright © 2009 Society of Chemical Industry  相似文献   
98.
A life cycle optimization model intended to potentially reduce the environmental impacts of energy use in commercial buildings is presented. A combination of energy simulation, life cycle assessment, and operations research techniques are used to develop the model. In addition to conventional energy systems, such as the electric grid and a gas boiler, cogeneration systems which concurrently generate power and heat are investigated as an alternative source of energy. Cogeneration systems appeared to be an attractive alternative to conventional systems when considering life cycle environmental criteria. Internal combustion engine and microturbine (MT) cogeneration systems resulted in a reduction of up to 38% in global warming potential compared with conventional systems, while solid oxide fuel cell and MT cogeneration systems resulted in a reduction of up to 94% in tropospheric ozone precursor potential (TOPP). Results include a Pareto-optimal frontier between reducing costs and reducing the selected environmental indicators.  相似文献   
99.
通过臭氧氧化改性方法制备含有大量含氧官能团的改性碳纳米管(CNT)。采用有机元素分析、X射线光电子能谱(XPS)元素分析以及Boehm滴定法分别测得样品的表面含氧量、总含氧量以及不同含氧官能团含量,并对产物的比表面积、孔体积和孔径进行测定。结果表明,改性后含氧功能团数量增加了3~7倍,并且这种臭氧改性技术受温度影响显著。然后,考察了改性CNT对铀的吸附性能,对吸附条件进行优化。结果表明,未经改性的CNT样品的吸附效果较差,铀去除率仅为78.0%,而改性后的CNT对铀的吸附效果有显著提高,铀去除率高达95.0%以上,表明含氧量的增加显著提高了改性物对铀的吸附效果。  相似文献   
100.
It is shown to be theoretically possible to balance out almost completely the total error in measurements with a three-wave ozone meter used to determine the total ozone content in the atmosphere. The working algorithm is given together with the theoretical basis for the compensation condition. __________ Translated from Izmeritel'naya Tekhnika, No. 8, pp. 66–68, August, 2005.  相似文献   
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