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Chinese Journal of Chemical Engineering 2024年第4期68卷 16-26页

作者： zhi Hu Jiahong Wang Tongtong Sun School of Environmental Science and Engineering Shaanxi University of Science&TechnologyXi'an 710021China Shaanxi Key Laboratory of Green Preparation and Functionalization of Inorganic Materials Xi'an 710021China

A novel tetraethylenepentamine(TEPA) functionalized magnetic mesoporous silica adsorbent(FNMs/TEPA) was prepared for the adsorption of Cr(Ⅲ)-ethylenediaminetetraacetic acid(EDTA)from wastewater. The characterization of the prepared adsorbent certified that TEPA was modified onto the magnetic mesoporous silicon(FNMs), while FNMs/TEPA maintained the ordered mesoporous and pristine magnetic properties. The batch adsorption experiments demonstrated that TEPA significantly enhanced the removal capacity of the adsorbent for Cr(Ⅲ)-EDTA. FNMs/TEPA exhibited an excellent adsorption property(13.84 mg·g-1) at p H 4.0. Even in the presence of high concentrations of coexisting ions and organic acids, the adsorption performance of FNMs/TEPA was stable. Experimental characterization and DFT demonstrated that the adsorption of Cr(Ⅲ)-EDTA was ascribed to the electrostatic interaction, hydrogen bonding, and complexation between Cr(Ⅲ)-EDTA and amino groups on the adsorbent surface. The analysis of the independent gradient model(IGM) shows that electrostatic interaction is the main mode of action in the adsorption process. Moreover, FNMs/TEPA demonstrated remarkable reusability in three regeneration cycles. These findings indicated that FNMs/TEPA possessed excellent application prospects in the disposal of wastewater containing Cr(Ⅲ)-EDTA.

关键词： TEPA functionalized magnetic mesoporous silicon Adsorption Cr(III)-EDTA Density functional theory calculations

Spatiotemporal variations of parameters of internal solitary waves in the northern South China Sea

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Journal of Oceanology and Limnology 2024年第2期42卷 421-438页

作者： Yu’ang LIU Yifei JIang Xiaojiang ZHang zhiyuan Wang Yu CAO Huizan Wang College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410000China

The dynamic parameters for internal solitary waves(ISWs)derived from the extended Korteweg-de Vries(eKdV)equation play an important role in the understanding and prediction of *** spatiotemporal variations of the dynamic parameters of the ISWs in the northern South China Sea(SCS)were studied based on the reanalysis of long-term temperature and salinity *** results for spectrum analysis show that there are definite geographical differences for the periodic variation of the parameters:in shallow water,all parameters vary with a wave period of one year,while in deep water wave components of the parameters at other frequencies *** wavelet analysis,the wavelet power spectral densities in deep water exhibited an inter-annual variation *** example,the wave component of the dispersion coefficient with a wave period of about half a year reached its power peak once every two *** on previous work,this inter-annual variation pattern was deduced to be caused by dynamic *** further work on the regulatory mechanisms,empirical orthogonal function(EOF)decomposition was *** was found that the modes of the dispersion coefficient have different geographical distributions,explaining the reason why the wave components in different frequencies appeared in different *** numerical simulation results confirm that the variations in the parameters of the ISWs derived from the eKdV equation could affect the waveforms significantly because of changes in the polarity of the ***,the periodic variations of the dynamic parameters are related to the geographical location because of dynamic processes operating.

关键词： internal solitary waves(ISWs) dynamic parameters eKdV equation spatiotemporal variation polarity empirical orthogonal function(EOF)decomposition

Effect of stress-relief annealing on thermal fatigue cracks for die-casting die steels

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Journal of Iron and Steel Research International 2024年第5期31卷 1164-1176页

作者： zhi-xiong Bai Xiao-chun Wu School of Materials Science and Engineering Shanghai UniversityShanghai200444China

The effect of stress-relief annealing at different stages of thermal fatigue tests on crack growth was investigated using a self-built thermal cycle *** results showed that annealing could limit crack expansion *** reduced dislocation density and released the accumulation of residual *** addition,the strain accumulation in carbides was reduced by this *** was also found that double annealing was even more effective at inhibiting crack expansion compared to single stress-relief *** 1000 cycles,the maximum crack length was reduced by 31.1%and 45.2%for the samples after using the optimal single and double annealing processes,*** single stress-relief annealing,earlier annealing provides more benefit in delaying crack ***,effective double stress-relief annealing requires a suitable time interval between the annealing ***,after 800 cycles,surface hardness decreased significantly accompanied by an increase in the size and number of carbides,and cracks expanded predominantly along grain boundaries.

关键词： Thermal fatigue Steel Carbide Stress-relief annealing Dislocation Residual stress

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CRH2C型动车组主变流器故障分析及处理

机车电传动 2011年第2期 70-71页

作者：张志昂林杰武汉铁路安全监督管理办公室驻武汉动车基地验收室湖北武汉430084

针对CRH2C型动车组在运用时主变流器控制电源异常和牵引变压器二次侧发生过电流故障原因进行了分析,介绍了CRH2C型动车组主变流器故障基本判断方法和处理措施,并应用于实际工作中,取得良好效果,从而提高了CRH2C型高速动车组运用检修质... 详细信息

针对CRH2C型动车组在运用时主变流器控制电源异常和牵引变压器二次侧发生过电流故障原因进行了分析,介绍了CRH2C型动车组主变流器故障基本判断方法和处理措施,并应用于实际工作中,取得良好效果,从而提高了CRH2C型高速动车组运用检修质量和故障处理能力。

关键词： CRH2C型动车组主变流器故障分析故障处理

氢氧化2,9,16,23-四羧基酞菁铁(Ⅲ)与咪唑类配体在水溶液中轴向配位反应热力学研究

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内蒙古大学学报（自然科学版） 2005年第2期36卷 152-154页

作者：周毅朱志昂包头师范学院化学系内蒙古包头014030 南开大学化学系天津300071

用分光光度法研究了酞菁铁[Fe(III)Pc(COOH)4OH]在碱性水溶液中与咪唑类配体的轴向配位反应热力学.测得了反应[Fe( )Pc(COO-)4·OH]4-+nL=[Fe( )Pc--(COO-)4Ln]3-+OH-的平衡常数K,配位数n,标准摩尔焓变△rH0m.

关键词：氢氧化2,9,16,23-四羧基酞菁铁(Ⅲ) 咪唑轴向配位反应热力学

Combination of diketone and PAO to achieve macroscale oil-based superlubricity at relative high contact pressures

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Friction 2024年第5期12卷 869-883页

作者： Shaonan DU Chenhui ZHang zhi LUO State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing100084China Beijing National Laboratory of Molecular Sciences CAS Key Laboratory of Engineering PlasticsInstitute of ChemistryChinese Academy of SciencesBeijing100190China

1-(4-ethylphenyl)-nonane-1,3-dione(0206)is an oil-soluble liquid molecule with rod-like *** this study,the chelate(0206-Fe)with octahedral structure was prepared by the reaction of ferric chloride and 1,*** experimental results show that when using 0206 and a mixed solution containing 60%0206-Fe and 40%0206(0206-Fe(60%))as lubricants of the steel friction pairs,superlubricity can be achieved(0.007,0.006).But their wear scar diameters(WSD)were very large(532µm,370µm),which resulted in the pressure of only 44.3 and 61.8 MPa in the contact areas of the friction *** 0206-Fe(60%)was mixed with PAO6,it was found that the friction coefficient(COF)decreased with increase of 0206-Fe(60%)in the *** the ratio of 0206-Fe(60%)to PAO6 was 8:2(PAO6(20%)),it exhibited better comprehensive tribological properties(232.3 MPa).Subsequent studies have shown that reducing the viscosity of the base oil in the mixed solution helped to reduce COF and increased *** the COF,contact pressure,and running-in time,it was found that the mixed lubricant(Oil3(20%))prepared by the base oil with a viscosity of 19.7 mPa·s(Oil3)and 0206-Fe(60%)exhibited the best tribological properties(0.007,161.4 MPa,3,100 s).

关键词： diketone oil-based lubricants chelate superlubricity

血清VEGF、TFF1、PG、EGF变化及其与胃溃疡病理过程的关系

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基因组学与应用生物学 2017年第8期36卷 3278-3284页

作者：周莲符明昌郑志昂海南省第三人民医院三亚572000

本研究探讨血清中血管内皮生长因子(VEGF)、组织三叶因子(TFF1)、胃蛋白酶原(PG)、表皮生长因子(EGF)变化及其与胃溃疡临床特征及愈合的关系。应用ELISA法测定活动性胃溃疡(n=68)、浅表性胃炎(n=60)健康对照组(n=60)血清VEGF、TFF1、PG... 详细信息

本研究探讨血清中血管内皮生长因子(VEGF)、组织三叶因子(TFF1)、胃蛋白酶原(PG)、表皮生长因子(EGF)变化及其与胃溃疡临床特征及愈合的关系。应用ELISA法测定活动性胃溃疡(n=68)、浅表性胃炎(n=60)健康对照组(n=60)血清VEGF、TFF1、PG、EGF水平。胃溃疡组均给予雷贝拉唑三联方案治疗,治疗前后均行14C-尿素呼气试验,胃镜下观察胃溃疡患者病理特征。胃溃疡组血清PG水平高于浅表性胃炎组及对照组(p<0.05),而TFF1、VEGF、EGF水平低于浅表性胃炎组及对照组(p<0.05),浅表性胃炎组血清PG水平高于对照组(p<0.05)。胃溃疡患者治疗后愈合率为58.82%(40/68),HP根治率为76.47%(52/68)。治疗后胃溃疡组炎症活动性评分、粘膜炎症反应评分较治疗前明显下降,而溃疡直径较治疗前显著减少(p<0.05)。治疗后未愈合组血清PG水平高于愈合组(p<0.05),而TFF1、VEGF、EGF水平低于愈合组(p<0.05)。治疗后HP(+)组血清PG水平高于HP(-)组(p<0.05),而TFF1、VEGF、EGF水平低于HP(-)组(p<0.05)。经Pearson单因素分析显示,血清PG水平与炎症活动性评分、粘膜炎症反应评分及溃疡面积呈正相关(p<0.05),而TFF1、VEGF、EGF水平与炎症活动性评分、粘膜炎症反应评分及溃疡直径呈负相关(p<0.05)。血清VEGF、TFF1、PG、EGF变化及其与胃溃疡病理特征及愈合有密切的关系,可作为评价胃溃疡发生及预后的有效指标。

关键词：血管内皮生长因子组织三叶因子胃蛋白酶原表皮生长因子胃溃疡临床特征愈合

低温太阳热与甲醇化学链整合能量释放机理实验初探

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工程热物理学报 2007年第2期28卷 181-184页

作者：何鹏洪慧金红光喻之昂北京科技大学机械工程学院北京100083 中国科学院工程热物理研究所北京100080

本文在低温太阳热能与CH_3OH-Fe2O_3化学链燃烧相结合控制CO_2分离动力系统的基础上,进一步探讨了低温太阳热能品位提升的内在规律,分别揭示出辐照强度与CH_3OH-Fe_2O_3反应特性、低温太阳热能品位提升的关联关系,本文采用溶胶凝胶法制... 详细信息

本文在低温太阳热能与CH_3OH-Fe2O_3化学链燃烧相结合控制CO_2分离动力系统的基础上,进一步探讨了低温太阳热能品位提升的内在规律,分别揭示出辐照强度与CH_3OH-Fe_2O_3反应特性、低温太阳热能品位提升的关联关系,本文采用溶胶凝胶法制作了Fe_2O_3反应颗粒,在热重反应器中进行了模拟太阳热能与甲醇化学链实验的初步研究,通过电镜,分析了反应前后金属氧化物的表面形貌特征。研究成果将为低温太阳热能与化学链燃烧整合能量释放新机理的研究提供理论依据和基础实验数据．

关键词：低温太阳热能甲醇化学链燃烧品位提升

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关联规则推荐的高效分布式计算框架

计算机学报 2019年第6期42卷 1218-1231页

作者：李昌盛伍之昂张璐曹杰南京财经大学信息工程学院南京210003 南京财经大学江苏省电子商务重点实验室南京210003 中国计算机学会(CCF)

关联规则推荐模型是在电子商务网站应用最广泛的商用推荐引擎之一,目前已有的工作大多聚焦于如何挑选高质量规则,以提升推荐精度.然而,关联规则数量庞大,且用户并发访问量通常极大,如何快速匹配用户浏览记录和关联规则库,为海量在线用... 详细信息

关联规则推荐模型是在电子商务网站应用最广泛的商用推荐引擎之一,目前已有的工作大多聚焦于如何挑选高质量规则,以提升推荐精度.然而,关联规则数量庞大,且用户并发访问量通常极大,如何快速匹配用户浏览记录和关联规则库,为海量在线用户产生近实时推荐,成为制约关联规则推荐能否胜任真实电子商务网站推荐的重要因素.为此,本文研究关联规则推荐的效率问题,提出服务于高效关联规则推荐的分布式计算框架,将规则挖掘与推荐计算无缝衔接.具体而言,本文首先设计有序模式森林,用于压缩存储频繁模式;然后将候选规则挖掘转化为森林上的路径搜索计算,并提出高效的单机路径搜索算法;最后提出负载均衡的数据分割策略,同时降低分布式规则挖掘与推荐计算中的任务最迟完成时间.在3个公开数据集的实验结果表明基于有序模式森林的推荐计算比传统穷举匹配策略降低6倍以上时间,同时所提出的分布式计算框架可随计算节点数量达到近线性扩展.

关键词：推荐系统关联规则频繁模式 FP-growth算法 Spark 负载均衡

Mixed Alkali-zinc Effects on Thermo-mechanical Properties in Borosilicate Glasses

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1093-1099页

作者： XIAO Guanzhou TAO Yunhang ZHOU Hemin ZHENG Qingshuang QIAO ang TAO Haizheng State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Wuhan University of Technology Advanced Engineering Technology Research Institute of Zhongshan City Zhongshan 528437China

A series of mixed alkali-zinc borosilicate glasses with various r values(r=molar ratio of[ZnO]/([R^(2)O]+[ZnO]))from 0.00 to 1.00 were fabricated to probe the mixed alkali-zinc effects on thermo-mechanical *** nonlinear evolution of glass transition temperature(T_(g))with the addition of ZnO is ascribed to the competition of two converse factors,i e,the T_(g)depression as one of the colligative properties for a solution,on the one hand,and the enhancement of T_(g)due to the higher field strength of zinc cations compared to that of alkali ***,the nonlinear evolution of elastic moduli and coefficients of thermal expansion with r is attributed to the variance of intermediate-range clusters,which is confirmed by infrared and Raman scattering *** findings are very helpful in tailoring the performance of borosilicate glasses.

关键词： glass transition temperature elastic moduli coefficient of thermal expansion borosilicate glass