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991.
转炉钢渣配烧水泥熟料,可降低能耗和成本,提高水泥产量和质量,具有显著的经济效益和环境效益.本文介绍了钢渣配烧水泥熟料的理论依据、生料制备、熟料煅烧和熟料分析检验,以及试生产情况. 相似文献
992.
高炉炉体冷却水水质稳定处理 总被引:1,自引:0,他引:1
用复合水稳药剂对高炉炉体冷却水进行水质稳定处理,系统处理后结垢附着速度0.14.m·c·m,腐蚀速度0.033mm/a.本法应用于石家庄钢铁厂高炉净环水. 相似文献
993.
994.
介绍了用高流量大气采样器和瓦特曼滤膜采集样品,以硝酸-高氯酸消化,无火焰原子吸收分光光度法测定海洋气溶胶中铜、铅、镉。对高流量大气采样流量校准、滤膜选用,仪器测试条件及消化方法进行试验和讨论。本方法检测限分别为铜1.8ng/m3、铅1.4ng/m3、镉0.7ng/m3,变异系数分别为铜9.6%、铅8.9%、镉18.0%。 相似文献
995.
Sudipta B. Sarmah B. Das A. Garg L. Gao R. K. Pai 《International Journal of Green Energy》2020,17(8):510-520
ABSTRACT Estimation of State of Health (SoH) of Lithium-ion (Li-ion) battery is essential to predict the lifespan of batteries of an electric vehicle (EV). The efficient prediction of battery health indicates to the effective and safe operation of EV. However, delivering an effective and accurate method for the estimation of SoH in the real condition is truly a challenging task. The present study proposed a holistic procedure of combining both experimental and numerical investigations to conduct the fundamental study on coupled mechanical-electrochemical behavior of Li-ion battery. The proposed investigation highlighted the effect of stress on the capacity of the battery, considering capacity fade as an equivalent parameter to its health for real-time estimation of SoH. Finally, a simple model of Artificial Neural Network (ANN) is provided, which shows the linear dependency of stress with the SoH. The results obtained from the ANN model are validated with a Linear Regression (LR) model for a better understanding of the inspection. The predicted value of mean Square Error (MSE) and R square error in the ANN training model are found to be 0.000309 and 0.849687, respectively. Whereas for the test model, these predicted values are found to be 0.000438 and 0.819347, respectively. 相似文献
996.
针对中空纤维膜应用于水力压裂返排液处理时存在的膜污染严重、通量衰减快、影响处理效率等问题,研究了PVDF固含量、凝固浴温度等因素对PVDF膜性能的影响,通过非溶剂致相分离法制备了PVDF中空纤维膜,并采用表面接枝技术,对PVDF中空纤维膜进行了表面亲水化改性。压裂返排液吸附实验结果表明,表面接枝降低了PVDF的接触角,提高了膜的亲水性。与未接枝改性的PVDF膜相比,亲水改性后的PVDF膜表面吸附的压裂返排液更少。将亲水性中空纤维膜用于页岩气水力压裂返排液的过滤处理,应用结果表明其对压裂返排液中的总铁、SS、浊度、细菌去除率达到90%以上,长时间运行后的通量保持率高,有较好的抗膜污染性。 相似文献
997.
制备了锰粉改进的规整化微电解填料,采用电化学辅助改进微电解填料处理初始COD为6 153.6 mg/L、ρ(NH_3-N)为182.6 mg/L的焦化废水,优化了工艺条件。实验结果表明,电化学辅助微电解法处理焦化废水的最佳工艺条件为电压8 V,填料投加量20 g/L,初始废水pH 6,反应时间30 min。在此条件下废水COD去除率为75.3%,NH_3-N去除率为65.4%;在其他工艺条件相同的情况下,未通过电化学辅助的填料微电解反应的COD去除率为33.0%,NH_3-N去除率为16.2%,电化学辅助后的COD去除率和NH_3-N去除率均明显提高。 相似文献
998.
Changzhou Xu Rongjun Qu Shasha Li Changmei Sun Ying Zhang Jingjing Gao Yuzhong Niu Qianli Ma Xiquan Song Shuangcheng Wang Chunxia Li 《Journal of Polymers and the Environment》2016,24(3):206-220
A series of nanaoscale aramid-based adsorbents were prepared by the functionalization of poly (p-phenylene terephthalamide) (PPTA) with different content of ethylenediamine (EDA). Their structures were characterized by field emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and elemental analysis. Metal ions, including Hg2+, Pb2+, Ag+, Cu2+, Cd2+, and Ni2+ were chosen as the models to explore the binding behaviors of PPTA–ECH–EDA in aqueous medium. Results showed that PPTA–ECH–EDA exhibited higher adsorption capacity for Hg2+ due to their nanoscale structures. In particular, the adsorption rate was so high that equilibrium was achieved within 15 min for Hg2+. The adsorption of Hg2+ on PPTA–ECH–EDA followed the pseudo second-order model well. Langmuir and Freundlich models were employed to fit the isothermal adsorption, and the results revealed that Freundlich isotherm was a better model to predict the experimental data. The adsorption mechanism was revealed by X-ray photoelectron spectroscopy. It is preconceived that PPTA–ECH–EDA could be used as an effective adsorbent for fast removal of heavy ions from wastewater. 相似文献
999.
Yan MA Naiyun GAO Wenhai CHU Cong LI 《Frontiers of Environmental Science & Engineering》2013,7(2):158-165
In this study, the adsorption performance of powdered activated carbon (PAC) on phenol was investigated in aqueous solutions. Batch adsorption studies were performed to evaluate the effects of various experimental parameters like PAC type, PAC dose, initial solution pH, temperature and pre-oxidation on the adsorption of phenol by PAC and establish the adsorption kinetics, thermodynamics and isothermal models. The results indicated that PAC adsorption is an effective method to remove phenol from water, and the effects of all the five factors on adsorption of phenol were significant. The adsorption rate of phenol by PAC was rapid, and more than 80% phenol could be absorbed by PAC within the initial 10 min. The adsorption process can be well described by pseudo-second-order adsorption kinetic model with rate constant amounted to 0.0313, 0.0305 and 0.0241 mg·μg -1·min -1 with coal, coconut shell and bamboo charcoal. The equilibrium data of phenol absorbed onto PAC were analyzed by Langmuir, Freundlich and Tempkin adsorption isotherms and Freundlich adsorption isotherm model gave the best correlation with the experimental data. Thermodynamic parameters such as the standard Gibbs free energy (?G o), enthalpy (?H o) and entropy (?S o) obtained in this study indicated that the adsorption of phenol by PAC is spontaneous, exothermic and entropy decreasing. 相似文献
1000.
地方性砷中毒地区环境砷暴露健康风险研究进展 总被引:2,自引:0,他引:2
自然因素引起的环境高砷暴露及其健康效应,尤其是饮水型地方性砷中毒是砷污染健康风险评估的基础。总结地方性砷中毒在环境砷暴露的风险识别、暴露途径和暴露与健康效应关系研究中的作用基础上,指出了地方性砷中毒研究中仅强调了饮水污染,关注的暴露途径比较单一,因此,人体多途径联合砷暴露的健康风险评估过程存在较大的不确定性。我国是唯一存在饮水和燃煤2种自然环境高砷暴露的国家,是研究2种类型砷暴露异同的天然场地,然而目前环境高砷的暴露及其健康效应的研究均为独立研究,对燃煤型地方性砷中毒在呼吸链砷暴露风险评估中的作用重视不够。因此,通过开展两种环境砷暴露及其健康效应的综合比较研究,建立呼吸链暴露评估和暴露-健康效应模型,可以为人体多途径联合砷暴露的健康风险研究提供新的依据。 相似文献