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Effect of Na^+ impregnated activated carbon on the adsorption of NH_4^+-N from aqueous solution

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Journal of Environmental Sciences 2013年第8期25卷 1501-1510页

作者： Mo Shi zhengfang wang Zheng Zheng Environmental Science and Engineering Department Fudan University

Two kinds of activated carbons modified by Na＋ impregnation after pre-treatments involving oxidation by nitric acid or acidification by hydrochloric acid （denoted as AC/N-Na and AC/HCl-Na, respectively）, were used as adsorbents to remove NH4＋-N. The surface features of samples were investigated by BET, SEM, XRD and FT-IR. The adsorption experiments were conducted in equilibrium and kinetic conditions. Influencing factors such as initial solution pH and initial concentration were investigated. A possible mechanism was proposed. Results showed that optimal NH4＋-N removal efficiency was achieved at a neutral pH condition for the modified ACs. The Langmuir isotherm adsorption equation provided a better fit than other models for the equilibrium study. The adsorption kinetics followed both the pseudo second-order kinetics model and intra-particle kinetic model. Chemical surface analysis indicated that Na＋ ions form ionic bonds with available surface functional groups created by pre-treatment, especially oxidation by nitric acid, thus increasing the removal efficiency of the modified ACs for NH4＋-N. Na＋-impregnated ACs had a higher removal capability in removing NH4＋-N than unmodified AC, possibly resulting from higher numbers of surface functional groups and better intra-particle diffusion. The good fit of Langmuir isotherm adsorption to the data indicated the presence of monolayer NH4＋-N adsorption on the active homogenous sites within the adsorbents. The applicability of pseudo second-order and intra-particle kinetic models revealed the complex nature of the adsorption mechanism. The intra-particle diffusion model revealed that the adsorption process consisted not only of surface adsorption but also intra-particle diffusion.

关键词： NH4+-N adsorption Na+-impregnated activated carbon isotherm kinetics mechanism

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基于HTRI的环己烷换热器的设计与优化

化工设备与管道 2024年第1期61卷 44-49页

作者：李凯王正方周志国张金成淄博职业学院智能制造学院山东淄博255000 山东理工大学机械工程学院山东淄博255000 淄博恒益化工技术有限公司山东淄博255000

环己烷换热器是精制提纯环己烷的重要设备之一,也是合成环己酮装置的重要组成部分,为环己酮的合成提供了原材料的保障。文章基于HTRI的设计和校核模型对环己烷换热器进行设计与优化,对换热器的主要优化参数进行分析,实现对换热器的更好... 详细信息

环己烷换热器是精制提纯环己烷的重要设备之一,也是合成环己酮装置的重要组成部分,为环己酮的合成提供了原材料的保障。文章基于HTRI的设计和校核模型对环己烷换热器进行设计与优化,对换热器的主要优化参数进行分析,实现对换热器的更好设计与优化。结果表明:基于HTRI进行优化设计,能够根据工艺要求设计提出多种设计方案,更有利于结合实际情况对环己烷换热器进行优化设计。

关键词：换热器 HTRI 设计优化

个性化运动干预对代谢综合征人群减重及代谢指标改善的效果分析

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中华健康管理学杂志 2024年第5期18卷 361-365页

作者：王郑芳张凤旭邹煦孙志颖张晗北京航天总医院健康管理中心北京100076

目的分析个性化运动干预对代谢综合征(MS)人群的减重效果。方法本研究为随机对照试验,选取2019—2022年在北京航天总医院健康管理中心进行健康体检的1200例MS患者为研究对象,采用随机数字表法分为试验组和对照组(各600例),结合患者体适... 详细信息

目的分析个性化运动干预对代谢综合征(MS)人群的减重效果。方法本研究为随机对照试验,选取2019—2022年在北京航天总医院健康管理中心进行健康体检的1200例MS患者为研究对象,采用随机数字表法分为试验组和对照组(各600例),结合患者体适能数据对试验组实施为期3个月的个性化运动干预,有氧运动3~4次/周结合抗阻运动≥2次/周,并给予MS相关健康体检;对照组仅给予健康体检。采用配对t检验比较两组干预前后体重及代谢相关指标变化,采用两样本t检验比较干预效果的组间差异,分析个性化运动干预对MS人群减重及代谢指标改善的效果。结果试验组干预后体重、体重指数、腰臀比、静息心率、收缩压、舒张压、空腹血糖、低密度脂蛋白、总胆固醇酯、甘油三酯水平均显著低于干预前[(72.5±12.9)比(74.2±13.6)kg、(27.3±3.5)比(27.9±3.5)kg/m^(2)、(0.87±0.08)比(0.91±0.08)、(71±7)比(74±9)次/min、(131±11)比(138±14)mmHg(1 mmHg=0.133 kPa)、(80±8)比(85±9)mmHg、(6.0±1.1)比(6.9±1.6)mmol/L、(2.78±0.78)比(3.12±0.77)mmol/L、(4.62±1.04)比(5.22±0.97)mmol/L、(1.36±0.42)比(2.59±2.01)mmol/L],高密度脂蛋白水平显著高于干预前[(1.31±0.31)比(1.27±0.29)mmol/L](均P<0.05)。对照组干预后体重、体重指数、腰臀比、收缩压、低密度脂蛋白、总胆固醇酯、甘油三酯水平均显著高于干预前[(68.1±5.9)比(67.1±5.9)kg、(25.3±2.4)比(24.9±2.4)kg/m^(2)、(0.83±0.07)比(0.82±0.06)、(127±12)比(125±12)mmHg、(3.50±1.45)比(3.20±1.21)mmol/L、(5.50±1.80)比(5.30±1.52)mmol/L、(1.59±0.82)比(1.40±0.65)mmol/L],高密度脂蛋白水平显著低于干预前[(1.28±0.28)比(1.38±0.28)mmol/L](均P<0.05)。试验组体重、体重指数、腰臀比、静息心率、收缩压、舒张压、空腹血糖、高密度脂蛋白、低密度脂蛋白、总胆固醇酯、甘油三酯等指标的干预效果均显著优于对照组[(-1.4±13.3)比(1.0±5.9)kg、(-0.6±3.5)比(0.4±2.4)kg/m^(2)、(-0.04±0.08)比(0.01±0.06)、(-3±8)比(0±7)次/min、(-7±12)比(2±12)mmHg、(-5±9)比(0±8)mmHg、(-0.9±1.4)比(0±0.5)mmol/L、(0.04±0.30)比(-0.10±0.28)mmol/L、(-0.34±0.77)比(0.30±1.34)mmol/L、(-0.60±1.00)比(0.20±1.66)mmol/L、(-1.23±1.45)比(0.19±0.74)mmol/L](均P<0.001)。结论对MS人群实施个性化运动干预能够促进MS患者减重并改善其代谢相关指标。

关键词：代谢综合征健康管理个性化运动干预减重

Influence of moderate pre-oxidation treatment on the physical, chemical and phosphate adsorption properties of iron-containing activated carbon

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Journal of Environmental Sciences 2014年第3期26卷 519-528页

作者： zhengfang wang Mo Shi Jihua Li Zheng Zheng Environmental Science and Engineering Department Fudan University

A novel adsorbent based on iron oxide dispersed over activated carbon （AC） were prepared, and used for phosphate removal from aqueous solutions. The influence of pre-oxidation treatment on the physical, chemical and phosphate adsorption properties of iron-containing AC were determined. Two series of ACs, non-oxidized and oxidized carbon modified by iron （denoted as AC-Fe and AC/O- Fe）, resulted in a maximum impregnated iron of 4.03% and 7.56%, respectively. AC/O-Fe showed 34.0%46.6% higher phosphate removal efficiency than the AC-Fe did. This was first attributed to the moderate pre-oxidation of raw AC by nitric acid, achieved by dosing Fe（II） after a pre-oxidation, to obtain higher iron loading, which is favorable for phosphate adsorption. Additionally, the in-situ formed active site on the surface of carbon, which was derived from the oxidation of Fe（II） by nitric acid dominated the remarkably high efficiency with respect to the removal of phosphate. The activation energy for adsorption was calculated to be 10.53 and 18.88 kJ/mol for AC-Fe and AC/O- Fe, respectively. The results showed that the surface mass transfer and intra-parficle diffusion were simultaneously occurring during the process and contribute to the adsorption mechanism.

关键词： adsorption per-oxidation iron-containing activated carbonphos phatemechanism

Oligo-fluoropolymer Modified Cycloaliphatic Epoxy Resins with Excellent Compatibility, Waterproof and Mechanical Properties for LED Encapsulation

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Chemical Research in Chinese Universities 2018年第2期34卷 326-332页

作者： SUN Yang LIU Weiqu wang zhengfang TAN Jianquan Guangzhou Institute of Chemistry Chinese Academy of Sciences Guangzhou 510650 P. R. China Key Laboratory of Cellulose and Lignocellulosics Chemistry of Chinese Aeademy of Sciences Guangzhou 510650 P. R. China University of ChineseAcademy of Sciences Beijing 100049 P. R. China

An oligo-fluoropolymer（PFM） with functional cycloaliphatic epoxy and fluorinated groups was obtained via free radical polymerization and applied to the modification of cycloaliphatic epoxy resins（CE）. The chemical structure of PFM was characterized by Fourier transform infrared（FT1R） spectroscopy, gel permeation chromatogra- phy（GPC） and nuclear magnetic resonance（NMR） spectroscopy, and the effects of different PFM concentra- tions（0.5%-6%, mass fraction） on the thermal resistance, mechanical properties, surface dewettability, light trans- mission, refractive index and various cured polymer properties were studied ha detail. The DSC and TGA results demonstrate that the modified epoxy resins possess a higher thermal resistance than the neat epoxy resin. The im- provements in the surface dewettability and water resistance are caused by the high crosslinking density and the enrichment of the oligo-fluorinated random copolymers dispersed in the matrix. The fracture surface morphologies of the thermosets were investigated by scanning electron microscopy（SEM） and transmission electron microsco- py（TEM）. It was observed that the optical transmittance of the composites was maintained even though microphase separation occurred during the curing process. With respect to the corresponding properties of the neat epoxy resins, the 2 phr（parts per hundreds of resin） PFM thermoset exhibited relatively better comprehensive properties, making the cured material a good candidate for light-emitting diode（LED） encapsulation.

关键词： Oligo-fluoropolymer Epoxy resin Light-emitting diode Encapsulate

不同成型方式精炼钢包包壁工作衬的蚀损机制研究

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耐火材料 2024年第4期58卷 344-348页

作者：李飞周辉杨枝超唐中队王正芳刘威宝钢股份武钢有限炼钢厂湖北武汉430081 武汉科技大学省部共建耐火材料国家重点实验室湖北武汉430081 武汉尚圆融信新型材料有限公司湖北武汉430080

为了探究浇注成型刚玉-尖晶石预制件与机压成型刚玉-尖晶石机压砖作为钢包包壁工作衬的服役情况及蚀损机制差异,研究了使用200炉次后的刚玉-尖晶石预制件以及机压砖的外观、化学成分、物相组成、物理性能以及显微结构。结果表明:刚玉-... 详细信息

为了探究浇注成型刚玉-尖晶石预制件与机压成型刚玉-尖晶石机压砖作为钢包包壁工作衬的服役情况及蚀损机制差异,研究了使用200炉次后的刚玉-尖晶石预制件以及机压砖的外观、化学成分、物相组成、物理性能以及显微结构。结果表明:刚玉-尖晶石预制件的蚀损速率略小于机压砖的,其侵蚀层厚度远小于机压砖的。免烧的机压砖本身颗粒之间的结合强度要远低于水泥结合预制件的,这导致机压砖内部颗粒之间的结合更容易被熔渣破坏,因此,预制件具有更优异的抵抗熔渣渗透的能力。

关键词：钢包包壁工作衬刚玉-尖晶石预制件刚玉-尖晶石机压砖蚀损机制

Characteristics of Pb^(2+) biosorption with aerobic granular biomass

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Chinese Science Bulletin 2008年第6期53卷 948-953页

作者： YAO Lei YE zhengfang wang ZhongYou NI JinRen Key Laboratory of Water and Sediment Sciences Department of Environmental Engineering Peking University Beijing 100871China

Experimental studies were conducted on the feasibility of aerobic granular biomass as a novel type of biosorbent for Pb2+ removal. The results show that the initial pH, Pb2+ concentration (C0) and biomass concentration (X0) affected the biosorption process significantly. Both the Freundlich and Langmuir isotherm models describe the biosorption process accurately, with correlation coefficients of 0.932 and 0.959 respectively. The Pb2+ biosorption kinetics is interpreted as having two stages, with the second stage described reasonably well by a Lagergren pseudo-second order model. Moreover, the surface change of granular biomass after the Pb2+ biosorption process appears to be caused by ion exchange and metal chelation according to the analysis results of Environmental Scanning Electron Microscopy (ESEM) and Energy Dispersive X-ray Spectroscopy (EDX).

关键词：需氧颗粒生物量铅离子生物吸附环境生物学

基于ERNIE-BiGRU-Attention-CRF的电子病历命名实体识别方法

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医学信息学杂志 2024年第5期45卷 76-82,100页

作者：王正芳张军亮李小倩于月陈慧媜新乡医学院卫生健康管理学院新乡453003 新乡医学院卫生信息资源研究中心新乡453003

目的/意义改善中文电子病历命名实体识别模型的性能,更好地开展医疗信息的组织和挖掘。方法/过程构建ERNIE-BiGRU-Attention-CRF中文电子病历命名实体识别模型,首先采用ERNIE1.0预训练模型生成具有语义特征的词向量,然后利用BiGRU捕获... 详细信息

目的/意义改善中文电子病历命名实体识别模型的性能,更好地开展医疗信息的组织和挖掘。方法/过程构建ERNIE-BiGRU-Attention-CRF中文电子病历命名实体识别模型,首先采用ERNIE1.0预训练模型生成具有语义特征的词向量,然后利用BiGRU捕获全局语义特征与语法结构特征,通过Attention机制进一步增强语义特征的捕获,最后连接CRF解码层输出全局概率最大的标签序列。结果/结论在公开的医疗文本数据集CCKS2017开展对比实验、消融实验,利用生成的模型进行实例分析,取得较好的识别效果。

关键词：命名实体识别 ERNIE 双向门控循环神经网络注意力机制条件随机场

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牛角瓜纤维性能及其应用

印染助剂 2024年第3期41卷 9-13页

作者：柴文波徐文齐王菁姚平李沛赢王正芳苏州经贸职业技术学院纺织服装与艺术传媒学院江苏苏州215000

牛角瓜纤维是一种新型天然植物纤维,有着特殊的中空结构,在环保及纺织印染领域有广泛的应用前景。主要从牛角瓜纤维的组成、结构和基本功能进行论述,系统介绍了牛角瓜纤维作为吸附材料在污染治理方面的应用,以及作为纺织材料在染色和纺... 详细信息

牛角瓜纤维是一种新型天然植物纤维,有着特殊的中空结构,在环保及纺织印染领域有广泛的应用前景。主要从牛角瓜纤维的组成、结构和基本功能进行论述,系统介绍了牛角瓜纤维作为吸附材料在污染治理方面的应用,以及作为纺织材料在染色和纺纱方面的应用。牛角瓜纤维作为一种优异的天然纤维材料,必将在未来得到广泛应用。

关键词：牛角瓜纤维组成结构吸附材料纺织材料