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891.
892.
我国太阳能光伏发电产业发展方向及产业政策 总被引:3,自引:0,他引:3
随着新世纪的到来,出于对环保和未来能源供应的考虑,可再生能源在世界能源消费中的比重逐渐加大。其中,太阳能光伏发电技术的发展和应用颇为世人所瞩目。本文从国有光伏产品市场特点出发,分析了国产光伏系统在市场竞争中的优势和劣势所在,指出了当前我国太阳能光伏发电系统企业在市场中缺乏竞争力的原因。在此基础上,提出相应的解决方案。 相似文献
893.
894.
卡鲁塞尔氧化沟反应器两相流PIV图像处理研究及实验分析 总被引:1,自引:0,他引:1
在单相数字粒子图像测速度(PIV)技术的基础上,研究了PIV两相流动的测试及图像处理方法.利用数学形态学的原理以及互相关法,对两相粒子图像进行标定、识别、区分和流场分析,编辑了相应的软件.并采用此技术对卡鲁塞尔氧化沟模型直道及弯道段二维液固两相流速进行测量,克服了传统点测量方法无法获取全场流动同步信息的缺陷,较好地反映了不同位置处固液流动分布的基本特性.结果表明,沟内径向流速远小于轴向,流速大小相差约一个数量级;同一断面上轴向流动分布是决定水力特性的主要因素;径向流速和水体动能是决定污泥沉积位置的主要因数,固相总体流速小于液相. 相似文献
895.
Jialin Tian Xuehua Hu Liming Dai Liang Zhang Heng Li Xiaoyue Lin 《International Journal of Green Energy》2020,17(6):363-372
ABSTRACTAs oil and gas production gradually shifts to deep and ultra-deep formations, the pressure and complexity of stratum is increased and drilling efficiency is decreased. Based on this, a Dual-diameter and bi-speed composite drilling method that can realize the different depth, diameter, and rotate speed coupling using only hole-bottom power is proposed in this paper. And a Dual-diameter and bi-speed composite drilling tool is designed, processed, and carried out to complete the field experiment. The tool is connected by a two-stage screw to make the rotate speed of a pilot bit higher than that of the reaming bit to increase the rate of penetration. And a concave bottom hole is formed so that the ground stress is released and the drillability of rock is lifted. Based on the introduction of the speed-up mechanism of the tool, the numerical analysis of the drilling performance of the tool with different diameter ratios and rotate-velocity combinations is completed. The experimental data showed that the Dual-diameter and bi-speed composite drilling method can obviously increase the rate of penetration and drilling efficiency, and also help to reduce the risk of stick-slip and prolong the service life of the drill bit. 相似文献
896.
Tian Li Guan Xiangjiu Dong Yuchen Zong Shichao Dai Anna Zhang Ziying Guo Liejin 《Environmental Chemistry Letters》2023,21(3):1257-1264
Environmental Chemistry Letters - Future carbon neutrality and the energy crisis are calling for advanced methods to produce sustainable fuels such as hydrogen production by photocatalytic water... 相似文献
897.
Hyperaccumulating potential of Bidens pilosa L. for Cd and elucidation of its translocation behavior based on cell membrane permeability 总被引:2,自引:0,他引:2
Dai Huiping Wei Shuhe Twardowska Irena Han Ran Xu Lei 《Environmental science and pollution research international》2017,24(29):23161-23167
Environmental Science and Pollution Research - Phytoremediation with the use of hyperaccumulating plant species to remove excess trace metals from contaminated soil and water is considered a... 相似文献
898.
Shuguang Liu Bo Tan Chaomeng Dai Sha Lou An Tao Guihui Zhong 《Environmental science and pollution research international》2015,22(24):20101-20113
899.
900.
Biosorption of clofibric acid and carbamazepine in aqueous solution by agricultural waste rice straw
Zhanguang Liu Xuefei Zhou Xiaohua Chen Chaomeng Dai Juan Zhang Yalei Zhang 《环境科学学报(英文版)》2013,25(12):2384-2395
Due to their widespread use, clofibric acid (CA) and carbamazepine (CBZ) have been frequently detected simultaneously at relatively high concentrations in aquatic environments. In this study, agricultural waste rice straw was employed as a potentially low-cost, effective and easy-to-operate biosorbent (RSB) to remove CA and CBZ. The adsorption of both pharmaceuticals followed pseudo second-order kinetics, and intraparticle diffusion was an important rate-limiting step. The adsorption isotherms of both drugs were fit well with Freundlich model. The adsorption of CA onto RSB was exothermic and was more likely to be dominated by physical processes, while the adsorption of CBZ was endothermic. Solution pH was determined to be the most important factor for CA adsorption, such that the adsorption capacity of CA onto RSB increased with the decline of solution pH. In the lower range of solution pH below 3. l, the CA removal efficiency was enhanced with the increase of biosorbent dosage. The CBZ removal efficiency was enhanced with the increase of RSB dosage without pH control. The maximum adsorption capacities were 126.3 mg/g for CA and 40.0 mg/g for CBZ. 相似文献