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Ammonia removal from low-strength municipal wastewater by powdered resin combined with simultaneous recovery as struvite

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Frontiers of Environmental Science & Engineering 2021年第1期15卷 125-134页

作者： kuo Fang Fei Peng hui Gong Huanzhen Zhang Kaijun Wang State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China School of Water Resources&Environment China University of GeosciencesBeijing 100083China

Low-strength municipal wastewater is considered to be a recoverable nutrient resource with economic and environmental ***,various technologies for nutrient removal and recovery have been *** this paper,powdered ion exchange resin was employed for ammonia removal and recovery from imitated low-strength municipal *** effects of various working conditions(powdered resin dosage,initial concentration,and pH value)were studied in batch experiments to investigate the feasibility of the approach and to achieve performance *** maximum adsorption capacity determined by the Langmuir model was 44.39 mg/g,which is comparable to traditional ion exchange ***,the effects of co-existing cations(Ca^(2+),Mg^(2+),K^(+))were *** on the above experiments,recovery of ammonia as struvite was successfully achieved by a proposed two-stage crystallization process coupled with a powdered resin ion exchange *** electron microscopy(SEM)and X-ray diffractometry(XRD)results revealed that struvite crystals were successfully gained in alkaline conditions(pH=10).This research demonstrates that a powdered resin and two-stage crystallization process provide an innovative and promising means for highly efficient and easy recovery from low-strength municipal wastewater.

关键词： Ammonia removal and recovery Powdered resin Crystallization process Struvite Co-existing cations

Pressure-induced bimetallic carbon nanotubes from metalorganic frameworks as optimized bifunctional electrocatalysts for water splitting

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Rare Metals 2023年第1期42卷 155-164页

作者： Hong-Xu Chen hui Xu Zhi-Rong Song Yi Liu hui Cui Jun-kuo Gao Key Laboratory of Rare Earth Optoelectronic Materials and Devices of Zhejiang Province Institute of Optoelectronic Materials and DevicesCollage of Optical and Electronic TechnologyChina Jiliang UniversityHangzhou310018China Institute of Functional Porous Materials School of Materials Science and EngineeringZhejiang Sci-Tech UniversityHangzhou310018China Institute for Composites Science Innovation School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China Argonne National Laboratory Physics DivisionLemontIL60439USA Department of Chemistry and International Institute for Nanotechnology(IIN) Northwestern UniversityEvanstonIL60208USA

Carbon nanotubes(CNTs)have attracted great interest in numerous applications due to their excellent electronic and structural ***,harsh synthesis conditions and high energy consumption limit the further application of ***,we developed a facile and innovative strategy to generate CNTs by physically pressurizing metal-organic frameworks(MOFs)and then *** synthesized bimetallic nitrogen/sulfur double-doped carbon nanotubes are denoted as Fe_(x)Co_(1-x)P(x=0.5,0.6,0.7,0.8,0.9).The introduction of pressure not only revolutionized the morphology of the electrocatalysts,but also enhanced the activity of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)in alkaline ***_(0.6)Co_(0.4)-P exhibits superior OER and HER performances in 1.0 mol·L^(-1)KOH solution with overpotentials of 364 and 346 mV at 10 mA·cm^(-2),which are 28 and 5 mV lower than unpressurized Fe0.6Co0.4.

关键词： Metal-organic frameworks(MOFs) Carbon nanotubes(CNTs) Bifunctional Pressurizing Oxygen evolution reaction(OER) Hydrogen evolution reaction(HER)

Revealing the effect of preparation parameters on zeolite adsorption performance for low and medium concentrations of ammonium

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Journal of Environmental Sciences 2019年第11期31卷 177-188页

作者： Wenyan He hui Gong kuo Fang Fei Peng Kaijun Wang State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Beijing 100084China School of Water Resources & Environment China University of Geosciences Beijing 100083 China

The effect of preparation parameters on the performance of zeolite for ammonium (20-300 mg N/L) adsorption from simulated wastewater is *** was found that the ratios of Na2O/SiO2 and Si/Al had a more important influence than crystallization time on zeolite adsorption *** low Na2O/SiO2 ratios were beneficial for fabrication of zeolites with high proportions of micropore area and volume,which led to the surface adsorption mechanism being dominated by surface free energy and pore ***,with decreasing Si/Al ratios,the effect of ion-exchange was more prominent due to the high negative surface potential of *** addition,the concentration of weak acid sites on the zeolites was increased with lower ratios of Na2O/SiO2 and Si/Al,which may promote ammonium ***,the most effective zeolite for ammonium removal,which was fabricated at Na2O/SiO2 =1.375,Si/Al =4 and crystallization time of 48 hr,exhibited the cooperative effects of adsorption,ion-exchange and a large amount of weak acid *** maximum ammonium adsorption capacity (35.06 t 0.98 mg/g) and the removal efficiency (94.44%± 4.00%) were obtained at the dosage of 4.0 g/L zeolite NaX at ammonium concentrations of 300 mg N/L and 20 mg N/L,*** Freundlich isotherm and pseudo-first-order kinetics models provided excellent fitting for the ammonium adsorption *** addition,zeolite NaX showed about 1.23-3.2 times the ammonium adsorption capacity of *** stable and efficient reusability of zeolite NaX after five regeneration cycles demonstrated that this adsorbent has considerable potential for practical industrial applications.

关键词： Zeolite synthesis Ammonium nitrogen removal Ion exchange Performance optimization

Synthesis of high-quality ferrovanadium nitride by carbothermal reduction nitridation method

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Journal of Iron and Steel Research International 2021年第3期28卷 255-262页

作者： ying-cong Zhou Yu Wang kuo-chih Chou Guo-hua Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China

High-quality ferrovanadium nitride(FeV45N,FeV55N and Fe65N)was fabricated using the raw materials of Fe_(3)O_(4),V_(2)O_(5) and graphite via carbothermal reduction nitridation *** with the traditional methods,it shortens the production process of ferrovanadium nitride by avoiding the preparation of *** effects of C/O molar ratio and reaction temperature on phase transition,density,carbon,oxygen and nitrogen contents and microstructure were *** appropriate C/O molar ratio is crucial to obtain the products with high nitrogen *** is also found that a higher temperature is beneficial for the densification,and the density of the products obtained at 1550℃ is much higher than that at 1500℃.Moreover,a higher temperature contributes to the increase in nitrogen content owing to the higher reaction *** carbothermal reduction nitridation method is proved to be a facile route to fabricate cost-effective ferrovanadium nitride and is possible to be applied for industrial production.

关键词： Ferrovanadium nitride Carbothermal reduction nitridation High nitrogen content Densification

甲基化SIM2、GNA12、CTGF在子痫前期孕妇中表达水平及其对疾病的预测价值

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国际检验医学杂志 2024年第1期45卷 44-48页

作者：张阔陈莹刘丹汪俊红唐山市妇幼保健院产科河北唐山063000

目的探究子痫前期孕妇血浆中甲基化DNA的表达水平及对子痫前期发生的预测价值。方法纳入2022年1-12月在该院确诊的82例子痫前期孕妇作为观察组,另外纳入82例健康孕妇作为对照组。提取患者游离总DNA,经过DNA亚硫酸氢盐修饰后通过实时... 详细信息

目的探究子痫前期孕妇血浆中甲基化DNA的表达水平及对子痫前期发生的预测价值。方法纳入2022年1-12月在该院确诊的82例子痫前期孕妇作为观察组,另外纳入82例健康孕妇作为对照组。提取患者游离总DNA,经过DNA亚硫酸氢盐修饰后通过实时荧光定量PCR反应(qRT-PCR)检测患者血浆中甲基化单意同源物2(SIM2)、结缔组织生长因子(CTGF)及鸟嘌呤核苷酸结合蛋白(GNA12)基因的相对表达水平,并采用相关性分析及受试者工作特征(ROC)曲线对各甲基化DNA预测子痫前期发生的价值进行评估。结果观察组血浆甲基化SIM2、GNA12、CTGF相对表达水平均高于对照组(P<0.05),且重度子痫前期孕妇各甲基化DNA相对表达水平更高(P<0.05)。相关性分析结果表明,血浆甲基化SIM2、GNA12、CTGF相对表达水平与孕妇发生子痫前期均呈正相关(P<0.05)。ROC曲线分析结果表明,血浆甲基化SIM2、GNA12、CTGF相对表达水平单独及联合检测对预测孕妇子痫前期的效能均较好,且三者联合检测的预测效能最高(曲线下面积为0.888,95%CI:0.827~0.949)。结论相较于健康孕妇,子痫前期孕妇血浆中甲基化SIM2、GNA12、CTGF相对表达水平均较高,且其与孕妇子痫前期的发生率呈正相关,血浆甲基化SIM2、GNA12及CTGF相对表达水平有望成为判断子痫前期是否发生的重要指标。

关键词：子痫前期甲基化DNA 单意同源物2 鸟嘌呤核苷酸结合蛋白结缔组织生长因子

全双工主动窃听非正交多址接入系统智能超表面辅助物理层安全传输技术

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电子与信息学报 2024年第3期46卷 798-807页

作者：阔永红曹琳吕璐贺冰涛陈健西安电子科技大学通信工程学院西安710071

针对全双工被动窃听和主动干扰攻击下的多用户非正交多址接入(NOMA)系统,该文提出一种智能超表面(RIS)辅助的鲁棒波束赋形方案以实现物理层安全通信。考虑在仅已知窃听者统计信道状态信息的条件下,以系统传输中断概率和保密中断概率作... 详细信息

针对全双工被动窃听和主动干扰攻击下的多用户非正交多址接入(NOMA)系统,该文提出一种智能超表面(RIS)辅助的鲁棒波束赋形方案以实现物理层安全通信。考虑在仅已知窃听者统计信道状态信息的条件下,以系统传输中断概率和保密中断概率作为约束,通过联合优化基站发射波束赋形、RIS相移矩阵、传输速率和冗余速率,来最大化系统的保密速率。为解决上述多变量耦合非凸优化问题,提出一种有效的交替优化算法得到联合优化问题的次优解。仿真结果表明,所提方案可实现较高的保密速率,且通过增加RIS反射单元数,系统保密性能更佳。

关键词：智能超表面非正交多址接入物理层安全波束赋形

酶-超声波辅助提取海蜇胶原蛋白及其组成分析

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中国调味品 2024年第6期49卷 70-76页

作者：薛宇鑫于阔跃董高缘袁颖吕艳芳季广仁李颖畅渤海大学食品科学与工程学院生鲜农产品贮藏加工及安全控制技术国家地方联合工程研究中心辽宁锦州121013 锦州笔架山食品有限公司辽宁锦州121007

为确定酶-超声波辅助提取海蜇胶原蛋白的最佳工艺,采用单因素实验和响应面实验对工艺进行优化,考察胃蛋白酶添加量、提取时间、超声时间、超声功率对海蜇胶原蛋白得率的影响,并对胶原蛋白的氨基酸组成和结构进行分析。结果表明,酶-超声... 详细信息

为确定酶-超声波辅助提取海蜇胶原蛋白的最佳工艺,采用单因素实验和响应面实验对工艺进行优化,考察胃蛋白酶添加量、提取时间、超声时间、超声功率对海蜇胶原蛋白得率的影响,并对胶原蛋白的氨基酸组成和结构进行分析。结果表明,酶-超声波辅助提取海蜇胶原蛋白的最佳条件为胃蛋白酶添加量1%、提取时间48 h、超声时间32 min、超声功率318 W,此时海蜇胶原蛋白得率为38.03%。甘氨酸是海蜇胶原蛋白中的主要氨基酸,为24.96%,海蜇胶原蛋白的紫外吸收峰位于235 nm处。在酰胺A、B带以及Ⅰ、Ⅱ、Ⅲ带中,有海蜇胶原蛋白的典型红外光谱特征吸收峰。该研究为海蜇深加工提供了理论基础。

关键词：海蜇胶原蛋白提取胃蛋白酶超声波

Statistical Characteristics of Austral Summer Cyclones in Southern Ocean

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Journal of Ocean University of China 2012年第2期11卷 118-128页

作者： LIU Na FU Gang kuo ying-Hwa Department of Marine Meteorology Ocean University of ChinaQingdao 266100P.R.China National Center for Atmospheric Research Mesoseale and Microscale Meteorology DivisionBoulder 80307USA

Characteristics of cyclones and explosively developing cyclones (or 'bombs') over the Southern Ocean in austral summer (December, January and February) from 2004 to 2008 are analyzed by using the Final Analysis (FNL) data produced by the National Centers for Environmental Prediction (NCEP) of the United States. Statistical results show that both cyclones and explosively developing cyclones frequently develop in January, and most of them occur within the latitudinal zone between 55°S and 70°S. These cyclones gradually approach the Antarctic Continent from December to February. Generally cyclones and bombs move east-southeastward with some exceptions of northeastward movement. The lifetime of cyclones is around 2-6 d, and the horizontal scale is about 1000 km. Explosive cyclones have the lifetime of about 1 week with the horizontal scale reaching up to 3000 km. Compared with cyclones developed in the Northern Hemisphere, cyclones over the southern ocean have much higher occurrence frequency, lower central pressure and larger horizontal scale, which may be caused by the unique geographical features of the Southern Hemisphere.

关键词： cyclone explosive cyclone Southern Hemisphere lifetime

春尺蠖热激蛋白AcinHsp70基因的克隆、分子特性与表达分析

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西南农业学报 2024年第1期37卷 128-136页

作者：陈龙朱圣杰崔阔澍路慧王靖郝雅娴河套学院农学系内蒙古巴彦淖尔015000 四川省农业技术推广总站成都610041

【目的】克隆春尺蠖热激蛋白Hsp70基因,分析其理化性质与表达情况,探究该基因在春尺蠖应对外界不利环境中的作用。【方法】基于前期所测转录组数据(春尺蠖幼虫不同低温胁迫),克隆获取Hsp70基因,命名为AcinHsp70(GenBank登录号:OP750249)... 详细信息

【目的】克隆春尺蠖热激蛋白Hsp70基因,分析其理化性质与表达情况,探究该基因在春尺蠖应对外界不利环境中的作用。【方法】基于前期所测转录组数据(春尺蠖幼虫不同低温胁迫),克隆获取Hsp70基因,命名为AcinHsp70(GenBank登录号:OP750249);利用生物信息分析软件对Hsp70基因的理化性质进行分析;采用qPCR技术检测AcinHsp70基因在不同温度(-10、-5、0、5和25℃)胁迫中回温与不回温及4℃不同时间处理下的表达谱。【结果】春尺蠖AcinHsp70基因完整CDS序列全长1899 bp,编码633个氨基酸,蛋白质预测分子量为69.91 kDa,预测等电点为5.51。在N端均不含信号肽且无跨膜区。磷酸位点检测分别发现丝氨酸、苏氨酸和酪氨酸磷酸位点24、26和8个;未发现糖基化位点。该蛋白的平均亲水性为-0.507,预测不稳定系数为33.19,故该蛋白属于亲水稳定蛋白,亚细胞定位结果显示,其主要位于细胞质。序列一致性比对与系统进化树分析结果显示,春尺蠖与庆网蛱蝶(Melitaea cinxia)亲缘关系最近,序列一致性达92.91%。基因表达结果显示,不同温度(-10℃除外)胁迫下,AcinHsp70基因表达量均无明显差异,回温后表达量显著上调。AcinHsp70基因表达量总体呈先升后降趋势,在4℃处理1 h后表达量达到最大值。【结论】AcinHsp70基因与春尺蠖应对低温胁迫的响应密切相关,结果有助于揭示该基因在低温胁迫下的分子功能。

关键词：春尺蠖热激蛋白70 分子特性低温胁迫表达谱

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