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Characteristics of change in water quality along reclaimed water intake area of the Chaobai River in Beijing, China

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Journal of Environmental Sciences 2016年第12期28卷 93-102页

作者： lei Yang jiangtao He Yumei Liu Jian Wang Lie jiang Guangcai Wang Beijing Key Laboratory of Water Resources and Environmental Engineering China University of Geosciences Beijing 100083 China Beijing Xinguohuan Environmental Technology Development Co. Ltd. Beijing 100044 China East China University of Technology Nanchang 330013 China jiangxi Institute of Geo-Environment Monitoring Nanchang 330012 China

To reveal the basic characteristics and controlling factors of water quality change in the project Wenyu to Chaobai reclaimed water diversion, the water quality in the study area was monitored for one year at seven monitoring sites. Inverse geochemical models of the statistical groups were developed using PHREEQC to elucidate the hydrochemistry characteristics of reclaimed water and the factors. The monitoring results indicated that nitrogen and phosphorus contents were significantly reduced along the river mainly caused by seasonal and location variation. The pH ranged from 7.44 to 9.81. Photosynthesis of algae and denitrification in anaerobic microenvironment ultimately led to a sudden pH increase after the Jian River and the Chaobai River confluence. Mg2＋ and SO^- levels dropped obviously in the summer and increased in winter seasons after intersection. Na＋ and C1- are relatively stable, and marked drop in the concentration only after the two rivers meet. And there is a decrease of Ca2＋ and HCO~ and increase in CO^- during monitoring period. As a whole, the primary ions and nutrient components, including nitrogen and phosphorus, had high levels in winter. Algae＇s photosynthesis and respiration were observed to have an impact on the river water quality; there was precipitation-dissolution of minerals and denitrification from upstream to downstream. Inverse geochemical PHREEQC modeling confirmed that there was precipitation of aragonite or calcite, and gypsum or anhydrite in summer, and dissolution in winter; as well as precipitation of dolomite in winter, and cationic exchange and denitrification along the river.

关键词： Reclaimed water Chaobai River Water quality PHREEQC

A novel energy storage system incorporating electrically rechargeable liquid fuels as the storage medium

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Science Bulletin 2019年第4期64卷 270-280页

作者： Haoran jiang lei Wei Xinzhuang Fan Jianbo Xu Wei Shyy Tianshou Zhao Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology Clear Water Bay

We propose a novel concept of energy storage that incorporates electrically rechargeable liquid fuels made of electroactive species, known as e-fuels, as the storage medium. This e-fuel energy storage system comprises an e-fuel charger and an e-fuel cell. The e-fuel charger electrically charges e-fuels, while the efuel cell subsequently generates electricity using charged e-fuels whenever and wherever on *** e-fuel energy storage system possesses all the advantages of conventional hydrogen storage systems,but unlike hydrogen, liquid e-fuels are as easy and safe to store and transport as gasoline. The potential efuel candidates have been identified to include inorganic electroactive materials, organic electroactive materials, and suspension of solid electroactive materials. In this work, we demonstrate an example efuel energy storage system for large-scale energy storage using inorganic e-fuels composed of V^(2+)/V^(3+) and VO_2^+/VO_2^+ redox couples, and compare the performance of the e-fuel energy storage system with that of existing technologies. Results show that our e-fuel charger achieves a charge efficiency of as high as～94%, while the e-fuel cell is capable of delivering a peak power density of 3.4 W cm^(-2), which is 1.7 times higher than that of hydrogen fuel cells. More excitingly, the e-fuel energy storage system exhibits a round-trip efficiency of 80.0% and an electrolyte utilization of 83.0% at an ultra-high discharge current density of 1,000 mA cm^(-2), which are 19.9% and 67.3% higher than those of conventional vanadium redox flow batteries. This unprecedented performance allows a 27.0% reduction in the capital cost of the e-fuel energy storage system compared with that of vanadium redox flow batteries.

关键词： Renewable energy Energy storage Batteries E-fuel energy storage system

A型扫查检测ISA 1932型流量计焊缝的研究

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无损探伤 2019年第5期43卷 7-11页

作者：罗昭强亚云启戴恩贤蒋磊龚杰宁波市特种设备检验研究院

利用A型扫查原理对ISA 1932型流量计两个环室短节之间的对接焊缝进行检测分析,首先提出如果环室短节直段足够长时,利用超声探头检测时可以将环室短节直段划分为6个扫查区域,并对分区依据及结果进行讨论;接着模拟NB/T 47013.3-2015所推荐... 详细信息

利用A型扫查原理对ISA 1932型流量计两个环室短节之间的对接焊缝进行检测分析,首先提出如果环室短节直段足够长时,利用超声探头检测时可以将环室短节直段划分为6个扫查区域,并对分区依据及结果进行讨论;接着模拟NB/T 47013.3-2015所推荐的K值为1.0、1.5、2.0以及非推荐的K值为0.8的超声探头对一台具体的ISA 1932型流量计进行检测分析,表明当K值为1.0、1.5、2.0时,环室短节直段长度并不满足探头扫查宽度所必须的长度,检验中存在着盲区,且若采用环室短节直段与斜段共同作为探头扫查宽度,能够有效地降低盲区。而当K值为0.8时,环室短节直段满足扫查所必须的扫查宽度,有效地消除了检验盲区。

关键词： A型扫查 ISA 1932型流量计对接焊缝检测

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喷射成形7055超高强铝合金锻件开裂原因

理化检验（物理分册） 2022年第5期58卷 62-66页

作者：单嗣宏张豪张捷陈思周张保玲江磊江苏豪然喷射成形合金有限公司镇江212000

某航空机轮用喷射成形7055超高强铝合金锻件在静压试验中提前开裂。结合锻件的热加工锻造工艺、热处理工艺和静压试验条件,采用宏观观察、电导率测试、力学性能测试、低倍组织检验、金相检验、断口及有限元模拟分析等方法,分析了锻件开... 详细信息

某航空机轮用喷射成形7055超高强铝合金锻件在静压试验中提前开裂。结合锻件的热加工锻造工艺、热处理工艺和静压试验条件,采用宏观观察、电导率测试、力学性能测试、低倍组织检验、金相检验、断口及有限元模拟分析等方法,分析了锻件开裂的原因。结果表明:该锻件在静压试验中开裂的失效模式属于一次性的过载断裂;由于其定位孔较深、根部直角应力集中,在螺栓定位孔径根部萌生裂纹,尖角处机轮锻件流线对裂纹的形成与扩展有促进作用。减小定位孔深度、增加孔径根部圆弧过渡处圆角、优化热处理工艺可以有效地提升该锻件静压试验的失效强度,使其满足验收要求。

关键词： 7055铝合金喷射成形锻件失效分析过载断裂应力集中

An improved implementable process for the synthesis of zeolite 4A from bauxite tailings and its Cr^(3+) removal capacity

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International Journal of Minerals,Metallurgy and Materials 2016年第7期23卷 850-857页

作者： Peng-cheng lei Xian-jiang Shen Yang Li Min Guo Mei Zhang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

A simple and practical method for the synthesis of zeolite 4A from bauxite tailings is presented in this paper. Systematic investigations were carried out regarding the capacity of zeolite 4A to remove Cr（III） from aqueous solutions with relatively low initial concentrations of Cr（III）（5–100 mg·L^（-1））. It is found that the new method is extremely cost-effective and can significantly contribute in decreasing environmental pollution caused by the dumping of bauxite tailings. The Cr（III） removal capacity highly depends on the initial p H value and concentration of Cr（III） in the solution. The maximum removal capacity of Cr（III） was evaluated to be 85.1 mg×g^（-1） for zeolite 4A, measured at an initial p H value of 4 and an initial Cr（III） concentration of 5 mg·L^（-1）. This approach enables a higher removal capacity at lower concentrations of Cr（III）, which is a clear advantage over the chemical precipitation method. The removal mechanism of Cr（III） by zeolite 4A was examined. The results suggest that both ion exchange and the surface adsorption-crystallization reaction are critical steps. These two steps collectively resulted in the high removal capacity of zeolite 4A to remove Cr（III）.

关键词： bauxite tailings zeolite trivalent chromium wastewater treatment

Effects of ionic strength and temperature on the aggregation and deposition of multi-walled carbon nanotubes

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Journal of Environmental Sciences 2017年第1期29卷 248-255页

作者： Lixin Wang Xuezhi Yang Qi Wang Yuxuan Zeng lei Ding Wei jiang Environment Research Institute Shandong UniversityJinan 250100China

The aggregation and deposition of carbon nanotubes（CNTs） determines their transport and fate in natural ***,the aggregation kinetics of humic-acid treated multi-walled carbon nanotubes（HA-MWCNTs） was investigated by time-resolved dynamic light scattering in NaCl and CaCl_2 electrolyte *** ionic strength induced HA-MWCNT aggregation due to the less negative zeta potential and the reduced electrostatic *** critical coagulation concentration（CCC） values of HA-MWCNTs were 80 mmol/L in NaCl and 1.3 mmol/L in CaCl_2 electrolyte,showing that Ca^（2＋） causes more serious aggregation than Na~＋.The aggregation behavior of HA-MWCNTs was consistent with Derjaguin-Landau-Verwey-Overbeek *** deposition kinetics of HA-MWCNTs was measured by the optical absorbance at 800 *** critical deposition concentrations for HA-MWCNT in NaCl and CaCl_2 solutions were close to the CCC values,therefore the rate of deposition cannot be increased by changing the ionic strength in the diffusion-limited aggregation *** deposition process was correlated to the aggregation since larger aggregates increased gravitational deposition and decreased random Brownian ***-MWCNTs hydrodynamic diameters were evaluated at 5,15 and 25℃.Higher temperature caused faster aggregation due to the reduced electrostatic repulsion and increased random Brownian motion and collision ***-MWCNTs aggregate faster at higher temperature in either NaCl or CaCl_2electrolyte due to the decreased electrostatic repulsion and increased random Brownian *** results suggest that CNT aggregation and deposition are two correlated processes governed by the electrolyte,and CNT transport is favored at low ionic strength and low temperature.

关键词： Carbon nanotubes Aggregation Deposition Electrolyte Temperature

抗病毒应答反应对HBV DNA高复制原发性肝癌根治术后疗效的影响

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福建医药杂志 2017年第1期39卷 93-95页

作者：蔡欣然陈燕凌蒋蕾陈江枝潘韡福建医科大学附属协和医院肝胆外科福州350001

目的探讨核苷类药物应答反应对HBV DNA阳性原发性肝癌根治术后复发的影响。方法对我科收治的157例HBV DNA高复制的原发性肝癌根治术患者,术后均予恩替卡韦抗乙肝病毒治疗;同期无抗病毒治疗的29例HBV DNA阴性肝癌根治术患者作为对照组。... 详细信息

目的探讨核苷类药物应答反应对HBV DNA阳性原发性肝癌根治术后复发的影响。方法对我科收治的157例HBV DNA高复制的原发性肝癌根治术患者,术后均予恩替卡韦抗乙肝病毒治疗;同期无抗病毒治疗的29例HBV DNA阴性肝癌根治术患者作为对照组。统计分析各患者的抗病毒应答反应、临床病理资料、肿瘤复发时间及无瘤生存期,及其各指标的相关性。结果 1)肝癌术后恩替卡韦治疗后24、48周HBV DNA转阴率为70.1%和90.2%;2)早期应答组、应答不良组、HBV DNA阴性组术后中位复发时间分别为26、20和28个月,早期应答组显著优于应答不良组(P=0.032),与阴性组比较无显著改变(P=0.242);3)早期应答组、应答不良组、HBV DNA阴性组术后1、3年的无瘤生存率分别为84.7%、73.0%、87.8%和39.7%、32.20%、40.3%,早期应答组显著优于应答不良组(P=0.024)。4)cox回归多因素分析脉管癌栓、手术切缘、肿瘤数目与肝癌术后近期复发显著相关;脉管癌栓、抗病毒应答、肿瘤分化与肝癌术后晚期复发显著相关。结论抗病毒早期应答有利于HBV DNA阳性肝癌患者根治术后延长复发时间和提高无瘤生存率。

关键词：肝肿瘤 HBV DNA 恩替卡韦病毒学应答疗效

二叶式主动脉瓣与三叶式主动脉瓣对TAVR术后患者左心室逆向重构的影响

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精准医学杂志 2021年第3期36卷 254-257页

作者：张甲易李贞福屈占军杨宝童江磊青岛大学附属医院心血管外科山东青岛266003

目的比较二叶式主动脉瓣(BAV)和三叶式主动脉瓣(TAV)对经导管主动脉瓣置换术(TAVR)后患者左心室逆向重构的影响。方法回顾性分析我院TAVR术后至少有3次连续超声心动图随访(1、3个月和1年)的67例患者的临床资料,比较BAV和TAV对经TAVR治... 详细信息

目的比较二叶式主动脉瓣(BAV)和三叶式主动脉瓣(TAV)对经导管主动脉瓣置换术(TAVR)后患者左心室逆向重构的影响。方法回顾性分析我院TAVR术后至少有3次连续超声心动图随访(1、3个月和1年)的67例患者的临床资料,比较BAV和TAV对经TAVR治疗后患者左心室逆向重构的影响。结果67例患者中BAV 23例,TAV 44例。两组患者术前基线资料比较差异无显著性(P>0.05);两组患者术后肺动脉收缩压(PASP)、左心室质量分数(LVMi)、相对室壁厚度(RWT)均随时间延长逐渐下降(F=3.64~25.59,P0.05)。结论BAV与TAV患者在接受TAVR术后均发生明显的左心室逆向重构,两者治疗效果相近。

关键词：心脏瓣膜疾病主动脉瓣经导管主动脉瓣置换心室重构治疗结果

碳氢酶烯类抗菌药物和替加环素在医院使用情况分析

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安徽医药 2020年第5期24卷 1027-1031页

作者：刘建军吕敏蒋磊刘俊王昊陈飞虎安徽省第二人民医院药学部安徽合肥230041 安徽医科大学第二附属医院药剂科安徽合肥230601 中国科学技术大学附属第一医院(安徽省立医院)检验科安徽合肥230001 安徽医科大学药学院安徽合肥230032

目的为临床合理使用碳氢酶烯类抗菌药物和替加环素提供参考依据。方法回顾性统计分析安徽省第二人民医院2018年1—6月碳氢酶烯类抗菌药物和替加环素的使用情况。结果碳氢酶烯类和替加环素共计使用647例,其中使用例数较多的为美罗培南和... 详细信息

目的为临床合理使用碳氢酶烯类抗菌药物和替加环素提供参考依据。方法回顾性统计分析安徽省第二人民医院2018年1—6月碳氢酶烯类抗菌药物和替加环素的使用情况。结果碳氢酶烯类和替加环素共计使用647例,其中使用例数较多的为美罗培南和比阿培南,分别为440例和176例;亚胺培南和替加环素占比较少,分别为24例和7例。用药合理率为68.16%,会诊率为49.61%,送检率达87.17%,非紧急情况下使用率为56.88%。结论该院住院病人的碳氢酶烯类抗菌药物和替加环素的应用较为合理,但仍存在少许不完善之处,亦需进一步结合国家卫生行政部门的相关政策法规加大管理力度,强化合理使用,保障安全用药。

关键词：药物利用评审碳氢酶烯类替加环素处方不当抗药性,细菌风险防控合理用药