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Facet-dependent activation of oxalic acid over hematite nanocrystals under the irradiation of visible light for efficient degradation of pollutants

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Journal of Environmental Sciences 2024年第8期142卷 204-214页

作者： Zhixiong Yang Yuan Li Xiaotian wang Jiaming Li jiquan wang Gaoke Zhang Hubei Key Laboratory of Mineral Resources Processing and Environment State Key Laboratory of Silicate Materials for ArchitecturesWuhan University of TechnologyWuhan 430070China Hubei Engineering Consulting Co. Ltd.Wuhan 430071China

Naturally occurring hematite has been widely studied in the Fenton-like system for water pollutant remediation due to its abundance and ***,its inadequate catalytic activity results in difficulty in effectively degrading pollutants in the catalytic degradation system that it ***,we constructed a photochemical system composed of hematite with{001}facet of high activity facet and low-cost and non-toxic oxalic acid(OA)for the removal of various types of *** removal rate for the degradation of metronidazole,tetracycline hydrochloride,Rhodamine B,and hexavalent chromium by hematite nanoplate with the exposed{001}facet activating OA under visible light irradiation was 4.75,2.25,2.33,and 2.74 times than that by the exposed{110}facet,*** functional theory(DFT)calculation proved that the OA molecule was more easily adsorbed on the{001}facet of hematite than that on the{110}facet,which would favor the formation of the more Fe(Ⅲ)-OA complex and reactive *** addition,the reactive site of metronidazole for the attraction of radicals was identified on the basis of the DFT calculation on the molecular occupied orbitals,and the possible degradation pathway for metronidazole included carbon chain fracture,hydroxyethyl-cleavage,denitrogenation,and ***,this finding may offer a valuable direction in designing an efficient iron-based catalyst based on facet engineering for the improved activity of Fenton-like systems such as OA activation.

关键词： Hematite Facet exposure Oxalic acid activation Fenton-like system Pollutant removal

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基于多物理场耦合方法的燃料性能分析模型研究及初步计算

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科学技术创新 2024年第14期 55-59页

作者：王继全中国原子能科学研究院北京

燃料棒是反应堆的核心部件,能够产生能量并包容强放射性物质,对其进行性能分析具有重要意义,传统的性能分析软件难以对复杂工况以及局部效应进行分析。近年来开始基于多物理场耦合平台对燃料性能进行分析。本工作基于COMSOL平台开发了... 详细信息

燃料棒是反应堆的核心部件,能够产生能量并包容强放射性物质,对其进行性能分析具有重要意义,传统的性能分析软件难以对复杂工况以及局部效应进行分析。近年来开始基于多物理场耦合平台对燃料性能进行分析。本工作基于COMSOL平台开发了棒状燃料的三维热-力-辐照耦合分析模型,考虑了芯块、包壳的物性随温度、燃耗等变化的模型以及燃料棒的一系列堆内行为。并以此对以SP-100为基础设计的新型燃料元件进行初步计算,具有一定的参考意义。

关键词：性能分析多物理场三维耦合有限元方法

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基于改进实数遗传算法的桑叶采摘机结构参数优化

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中国农机化学报 2024年第1期45卷 14-20,53页

作者：王吉权宋丽宋豪豪张攀利王福林东北农业大学工程学院哈尔滨市150030

针对遗传算法在求解桑叶采摘机结构优化问题时容易陷入局部最优和求解精度低等问题,提出一种改进实数遗传算法。首先是给出一种基于序的组合适应度函数的轮盘赌选择算子,该算子在轮盘赌的基础上,通过一个自适应变化的参数在两种适应度... 详细信息

针对遗传算法在求解桑叶采摘机结构优化问题时容易陷入局部最优和求解精度低等问题,提出一种改进实数遗传算法。首先是给出一种基于序的组合适应度函数的轮盘赌选择算子,该算子在轮盘赌的基础上,通过一个自适应变化的参数在两种适应度函数中选择一个,再去计算适应度值;然后设计一种基于方向的改进启发式交叉算子,该算子既保留两个父代个体中较优个体对子代个体的影响,又增加种群中最优个体对子代个体的影响,提高交叉产生有潜力子代的可能性。接着将改进算法应用于摇杆式桑叶采摘机的优化参数设计中,通过与其他算法作仿真对比试验验证算法的优越性,获得采摘机最优参数组合:行走结构速度为24 mm/s、拨动结构角速度为1.2 rad/s、采摘结构速度为440 mm/s,并由运行结果可知整机性能与优化前相比提高13%。最后用优化得到的参数组合进行实地试验,结果显示桑叶采摘机性能提升10.9%,误差较小为2.1%。可见,所提改进实数遗传算法是优化采摘机参数的一种有效算法。

关键词：桑叶采摘机结构优化实数遗传算法轮盘赌选择启发式交叉算子

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MS-G技术调控Nd-Fe-B铸态组织研究

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中国稀土学报 2024年第1期42卷 47-52,I0002页

作者：马斌张鹏杰王继全李青华李炳山孙威矿冶科技集团有限公司北京102600 北矿磁材(阜阳)有限公司安徽阜阳236000

采用熔体快淬+晶体生长(MS-G)技术调控Nd-Fe-B铸态组织,研究了铜辊转速及高温热处理对Nd-Fe-B快淬条带组织结构的影响。铜辊转速25 m·s^(-1)时快淬条带微观晶粒组织均匀,平均晶粒尺寸0.1μm,XRD图谱显示其为Nd_(2)Fe_(14)B相。Nd-Fe-B... 详细信息

采用熔体快淬+晶体生长(MS-G)技术调控Nd-Fe-B铸态组织,研究了铜辊转速及高温热处理对Nd-Fe-B快淬条带组织结构的影响。铜辊转速25 m·s^(-1)时快淬条带微观晶粒组织均匀,平均晶粒尺寸0.1μm,XRD图谱显示其为Nd_(2)Fe_(14)B相。Nd-Fe-B快淬条带经880℃热处理2.0 h晶粒均匀长大,平均尺寸0.86μm;冷却到750℃继续热处理2.0 h晶粒进一步均匀长大,平均尺寸达到1.04μm。温度升高会降低Nd_(2)Fe_(14)B晶粒异常长大临界驱动力Δg_(c),缩短异常长大的孕育期,使异常晶粒提早出现,高温+低温两步热处理通过降温处理来延长晶粒异常长大孕育期,从而促进Nd_(2)Fe_(14)B晶粒在较低温度下继续均匀长大。

关键词：钕铁硼熔体快淬晶体生长两步热处理铸态组织

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环氧树脂粘度和充磁次数对两步室温压各向异性粘结Nd-Fe-B磁体性能的影响

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中国稀土学报 2024年第4期42卷 705-711,I0003页

作者：马斌张鹏杰王继全李青华李炳山孙威矿冶科技集团有限公司北京102600 北矿磁材(阜阳)有限公司安徽阜阳236000

采用两步室温压工艺即室温预成型+高温取向成型制备各向异性粘结Nd-Fe-B磁体,研究了环氧树脂粘度和交变磁场充磁次数对磁体性能的影响。环氧树脂在140℃时粘度较小(约150 Pa·s)且具有一个较长的低粘度平台(约200 s),预成型坯体在140℃... 详细信息

采用两步室温压工艺即室温预成型+高温取向成型制备各向异性粘结Nd-Fe-B磁体,研究了环氧树脂粘度和交变磁场充磁次数对磁体性能的影响。环氧树脂在140℃时粘度较小(约150 Pa·s)且具有一个较长的低粘度平台(约200 s),预成型坯体在140℃保温1 min时预热效果最好,制备的粘结磁体具有最高的最大磁能积((BH)_(max))、取向度(DOA)和密度(127 kJ·m^(-3),0.55,5.91 g·cm^(-3))。140℃保温1 min时,粘结磁体(BH)_(max),DOA在交变磁场充磁2次时达到最大值(133 kJ·m^(-3)、0.59);140℃保温6 min时,粘结磁体(BH)_(max),DOA在交变磁场充磁4次时达到最大值(108 kJ·m^(-3)、0.52);密度则随着交变磁场充磁次数的增加逐渐降低。随着保温时间的延长,环氧树脂粘度增大,流动性降低,导致粘结磁体(BH)_(max),DOA和密度降低,可以通过增加交变磁场充磁次数使粉末颗粒向磁场方向转动来提高磁体DOA,进而提高(BH)_(max)。

关键词：粘结Nd-Fe-B磁体环氧树脂粘度交变磁场

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大跨径钢-UHPC组合梁桥设计与整体受力分析

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城市道桥与防洪 2024年第4期 71-73,I0005页

作者：王继全刘晓銮上海市政工程设计研究总院(集团)有限公司上海市200092

嘉兴市市区快速路环线工程跨越京杭大运河地面老桥龙凤桥,采用跨径布置为65 m+95 m+65 m的大跨径钢-UHPC连续组合梁方案,该方案在设计、施工和经济性方面都具有较显著的优势.采用Midas Civil 2021软件建立桥梁空间有限元模型,在承载能... 详细信息

嘉兴市市区快速路环线工程跨越京杭大运河地面老桥龙凤桥,采用跨径布置为65 m+95 m+65 m的大跨径钢-UHPC连续组合梁方案,该方案在设计、施工和经济性方面都具有较显著的优势.采用Midas Civil 2021软件建立桥梁空间有限元模型,在承载能力极限状态和正常使用极限状态下各项验算均满足规范要求,可以为类似桥梁设计提供参考.

关键词：超高性能混凝土(UHPC) 组合梁经济性承载力有限元分析

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Promotional effect of silica on the combustion of nano-sized aluminum powder in carbon dioxide

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Chinese Journal of Aeronautics 2022年第4期35卷 245-252页

作者： Baozhong ZHU Jinghui wang Qichang wang Yunlan SUN Weiqi CHEN jiquan wang School of Petroleum Engineering Changzhou UniversityChangzhou 213164China School of Energy and Environment Southeast UniversityNanjing 243002China

This paper presents how the combustion performance of nano-sized aluminum(nAl)powder in carbon dioxide are affected by silica. The ignition and combustion performance of nAl powder with silica addition were studied by a high-temperature tube furnace. An s-type thermocouple and a high-speed motion acquisition instrument were performed to evaluate the ignition temperature, maximum combustion temperature, maximum change of rate of temperature, and combustion propagation speed. The combustion efficiency and combustion products were measured and analyzed by a gas-volumetric method and an X-ray diffraction. The results show that silica added into nAl powder can enhance its maximum combustion temperature and maximum change of rate of temperature, while its ignition temperature increases slightly. The nAl powders with addition of 6.00 wt.% and 12.00 wt.% silica present high combustion propagation speeds, especially for the latter, it has high combustion efficiency. The effect mechanism of silica on the combustion of nAl powder in carbon dioxide was discussed.

关键词： Combustion Mechanism Nano-sized aluminum powder Promotional effect Silica

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Establishment and verification of labor demand estimation model in planting industry

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International Journal of Agricultural and Biological Engineering 2017年第6期10卷 86-93页

作者： Xu Bing wang Fulin wang jiquan Zhao Shengxue College of Engineering Northeast Agricultural UniversityHarbin 150030China

In view of the poor precision of the theoretical model of labor demand estimation,it is difficult to estimate and predict the actual production problems *** on the actual production conditions and the relationship between the degree of mechanization of planting and the demand of labor force,this study established an estimation model for the labor demand of planting industry considering the factors of planting structure and mechanization *** order to ensure high reliability of data,the method of checking out abnormal data was adopted to obtain the cultivated land area index when the mechanization degree is from 0 to 100%.Taking Suihua region(Heilongjiang Province,China)as an example,the theory of the research was analyzed and *** study accessed to the data of cultivated land area per labor can afford when the mechanization level in Suihua area were 0 and 100%respectively through the investigation,and the average cultivated land area data of each labor force in two cases were sorted out and the abnormal data were eliminated at the same ***,using the derived model,the data obtained and the mechanization level and cultivated land area of Suihua in the future,the labor demand amount in Suihua area from 2015 to 2019 were *** model established in this study can be used to calculate the quantity of both current labor demand in planting industry and the labor demand in the various moments in the future through forecasting the future mechanization level and cultivated area which are the two main factors influencing the quantity of labor demand in planting structure.

关键词： planting industry labor estimation model case verification forecast evaluation

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Adsorption of Rhodamine B from Aqueous Solution onto Heat-Activated Sepiolite

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Wuhan University Journal of Natural Sciences 2013年第3期18卷 219-225页

作者： wang jiquan wang Daojie ZHANG Gaoke GUO Yadan LIU Jin School of Resources and Environmental Engineering Wuhan University of Technology

The heat-activated sepiolite,which was prepared using sepiolite by thermal treatment at different temperatures,was used as an absorbent for the removal of rhodamine B（RhB） from aqueous *** structure and morphology of the as-prepared samples were characterized by X-ray diffraction（XRD） and scanning electron microscopy（SEM） techniques,*** adsorption capacity of RhB onto the heat-activated sepiolite has been examined with pH,adsorbent dosage,contact time,initial dye concentration,and *** studies showed that the equilibrium was attained within 40 min,and the kinetic data were well described by the pseudo-second-order kinetic ***,the experimental data（R 2 〉0.999） fitted the Freundlich model better than the Langmuir *** as-prepared sample showed higher adsorption capacity（8.33 mg/g） for the removal of RhB than that of sepiolite,which could be attributed to more adsorption sites caused by appropriate heat *** adsorbent can be well regenerated by calcination at 400 ℃ for 2 h and regenerated sepiolite did not exhibited significant loss of adsorption activity after five recycles.

关键词： heat-activated sepiolite adsorption rhodamine B kinetics adsorption isotherms

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Effects of bias voltage on coating structures and anticorrosion performances of PA-PVD Al coated NdFeB magnets

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Journal of Rare Earths 2021年第6期39卷 703-711,I0004页

作者： Yujie Cao Pengjie Zhang Wei Sun Weifeng Zhang Hanzhong Wei jiquan wang Bingshan Li Xiaofei Yi Guangqing Xu Yucheng Wu School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China State Key Laboratory of Rare Earth Permanent Magnet Materials Earth-Panda Advance Magnetic Material Co.Ltd.Hefei 231500China BGRIMM Magnetic Materials and Technology(Fu Yang)Co. Ltd.Fuyang 236000China BGRIMM Technology Group Co. Ltd.Beijing 102600China

Al coated NdFeB magnets were prepared by plasma-assisted-physical-vapor-deposition(PA-PVD)method fo r enhancing the corro sion *** rphologies and structures were characterized by an Xray diffractometer and a scanning electron *** behaviors of the samples with different bias voltages were studied by electrochemical methods and neutral salt spray test,*** bias voltage during the deposition process was optimized according to the coating structures and corrosion *** density and flatness of Al coating increase with increasing the bias voltage,and at the same time the thickness *** coating density and thickness turn to be stable when bias voltage is 1800 ***,the corrosion behaviors of PA-PVD Al coatings in different media,such as NaOH,HNO_(3) and NaCl solutions,were *** self-corrosion potentials(E_(corr)) of PA-PVD Al coatings almost keep constant in NaOH and HNO_(3) solutions with diffe rent ***,the self-corrosion current densities(J_(corr)) decrease with the increasing concentrations.E_(corr) shifts to negative potential and J_(corr)decreases gradually when increasing the concentration of NaCl *** corrosion mechanisms of Al coatings are discussed based on the corrosion behaviors in different media.

关键词： Physical vapor deposition Plasma assistance Al coating Sintered NdFeB Corrosion behavior Rare earths

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