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A density functional theory study on the interaction between UO_2^(2+) and the carbamoylphosphoramidic acid ligand for uranium extraction from seawater

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Nuclear Science and Techniques 2018年第6期29卷 128-140页

作者： Xiao-Jing Guo Cheng Li Jiang-Tao Hu hong-juan ma hong-Liang Qian Shanghai Institute of Applied Physics Chinese Academy of Sciences School of Engineering China Pharmaceutical University

Phosphorylurea molecules, which contain both phosphoryl and carbonyl groups, are considered efficient extractants for UO_2^(2+). This study aims to explain the complexation of UO_2^(2+)with carbamoylphosphoramidic acid(CPO), a simple model for phosphorylurea, for ligand design for uranium recovery from seawater using density functional theory calculations, natural bond order analysis,and the quantum theory of atoms in molecules. The results showed that, when CPO acts as a monodentate ligand, the affinity of phosphoryl for UO_2^(2+)is stronger than that of carbonyl, and CPO coordinates with UO_2^(2+)through the phosphoryl oxygen atom. When CPO serves as a bidentate ligand, both the phosphoryl and carbonyl oxygen atoms connect to UO_2^(2+), and the U–O(carbonyl) bond plays a more important role than the U–O(phosphoryl) bond in the interaction between UO_2^(2+)and CPO. This paradox may be caused by the significant charge transfer from the U–O(carbonyl) p bond orbital to the C–N σ antibond orbital of the bidentate CPO. The NH spacer between the phosphoryl and carbonyl groups could ensure the delocalization of the electron system of the molecule. The bidentate binding motif is favored by entropy and opposed by enthalpy, while the monodentate binding motif is favored by enthalpy and opposed by entropy. Ultimately, the bidentate binding motif is more favorable than the monodentate one. As expected, the interaction between UO_2^(2+)and the deprotonated CPO is stronger than that between UO_2^(2+)and the neutral CPO. Comparing the interaction between UO_2^(2+)and CPO with that between UO_2^(2+)and Nphenylcarbamoylphosphoramidic acid(Ph CPO), formed by replacing one hydrogen atom from the terminal nitrogen atom of CPO with a phenyl group, the phenyl substituent at the terminal nitrogen atom of Ph CPO shows a slightly negative effect on the interaction between UO_2^(2+)and Ph CPO.

关键词：相互作用理论学习海水密度抽取 CPO 铀苯基取代

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Amidoxime-based adsorbents prepared by cografting acrylic acid with acrylonitrile onto HDPE fiber for the recovery of uranium from seawater

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Nuclear Science and Techniques 2017年第4期28卷 13-18页

作者： Lu Xu Jiang-Tao Hu hong-juan ma Chang-Jian Ling Mou-Hua Wang Rong-Fang Shen Xiao-Jing Guo Yin-Ning Wang Jing-Ye Li Guo-Zhong Wu Shanghai Institute of Applied Physics Chinese Academy of Sciences Nuclear and Radiation Safety Center Ministry of Environmental Protection of the People's Republic of China

An amidoxime-based polymeric adsorbent was prepared by pre-irradiation grafting of acrylonitrile and acrylic acid onto high-density polyethylene fibers using electron beams,followed by *** recovery of uranium was investigated by flow-through experiment using simulated seawater and marine test in natural *** maximum amount of uranium uptake was 2.51 mg/g-ads after 42 days of contact with simulated seawater and 0.13 mg/g-ads for 15 days of contact with natural seawater.A lower uranium uptake in marine test can be attributed to the short adsorption time and the contamination of marine microorganisms and ***,the high selectivity toward uranium against vanadium may be beneficial to harvest uranyl ion onto adsorbents and the economic feasibility for recovery of uranium from seawater.

关键词： Radiation-induced grafting Amidoxime Acrylonitrile Uranium Selectivity

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Preparation of amidoxime-based PE/PP fibers for extraction of uranium from aqueous solution

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Nuclear Science and Techniques 2019年第2期30卷 39-51页

作者： Xiao Xu Xiao-Jun Ding Jun-Xuan Ao Rong Li Zhe Xing Xi-Yan Liu Xiao-Jing Guo Guo-Zhong Wu hong-juan ma Xiao-Yan Zhao School of Petrochemical Engineering Changzhou University Shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

A novel amidoxime-based fibrous adsorbent,denoted as PE/PP-g-(PAAc-co-PAO), was prepared by preirradiation grafting of acrylic acid and acrylonitrile onto polyethylene-coated polypropylene skin-core(PE/PP)fibers using 60 Co γ-ray irradiation, followed by amidoximation. The original and modified PE/PP fibers were characterized by a series of characterization methods to demonstrate the attachment of amidoxime groups onto the PE/PP fibers. Breaking strength tests confirmed that the fibrous adsorbent could maintain good mechanical properties. The adsorption capacity of the PE/PP-g-(PAAc-coPAO) fibers was investigated in simulated seawater with an initial uranium concentration of 330 μg/L. The uranium adsorption capacity was 2.27 mg/g-adsorbent after 24 h in simulated seawater, and the equilibrium data were well described by the Freundlich isotherm model. The PE/PP-g-(PAAc-co-PAO) adsorbent exhibited good regeneration and recyclability during five adsorption-desorption *** adsorption test was also performed in simulated radioactive effluents with uranium concentrations of 10 and100 μg/L. The effect of the pH value on the adsorption capacity was also studied. At a very low initial concentration 10 μg/L solution, the PE/PP-g-(PAAc-co-PAO)fiber could remove as much as 93.0% of the uranium, and up to 71.2% of the uranium in the simulated radioactive effluent. These results indicated that the PE/PP-g-(PAAcco-PAO) adsorbent could be used in radioactive effluents over a wide range of pH values. Therefore, the PE/PP-g-(PAAc-co-PAO) fibers, with their high uranium selectivity,good regeneration and recyclability,good mechanical properties, and low cost, are promising adsorbents for extracting uranium from aqueous solutions.

关键词： Amidoxime groups Pre-irradiation PEcoated PP skin-core fiber Adsorption Uranium

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泪道支架术后再次梗阻280眼原因探析

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国际眼科杂志 2017年第12期17卷 2354-2355页

作者：杨伟马鸿娟哈少平宁夏回族自治区人民医院宁夏眼科医院中国宁夏回族自治区银川市750021

目的:探讨泪道支架术后再次梗阻原因。方法:对泪道支架患者523例523眼,术前检查眼部鼻腔相关情况,观察泪道阻塞与相关疾病关系,泪道支架术后平均随访2a。其中280眼再次梗阻,观察分析再次梗阻原因。结果:泪道阻塞往往继发于结膜或鼻腔黏... 详细信息

目的:探讨泪道支架术后再次梗阻原因。方法:对泪道支架患者523例523眼,术前检查眼部鼻腔相关情况,观察泪道阻塞与相关疾病关系,泪道支架术后平均随访2a。其中280眼再次梗阻,观察分析再次梗阻原因。结果:泪道阻塞往往继发于结膜或鼻腔黏膜的炎症蔓延。高位阻塞与慢性结膜炎关系密切,低位阻塞与下鼻甲肥大关系更密切。两种支架拔除后再次阻塞都是其失败的首要原因。环形支架术后发生低位梗阻为其再次梗阻的第二位因素。而球头型支架再梗阻第二位因素为术后继发高位泪道阻塞。结论:泪道支架手术安全、简单,门诊治疗方便,但随植入支架时间延长疗效逐年减低。应根据泪道阻塞患者的可能病因、泪道阻塞部位、年龄、治疗情况,制定个性的综合治疗方案。

关键词：泪道阻塞支架疗效

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夹层玻璃等效厚度计算方法研究

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武汉理工大学学报 2009年第22期31卷 106-109页

作者：庞世红马眷荣马振珠中国建筑材料科学研究总院北京100024

根据夹层复合材料弯曲理论,计算了夹层玻璃层间应力。计算夹层玻璃等效厚度时引入了剪力比系数ξ,即同样载荷条件下,夹层玻璃层间应力与同样尺寸、厚度的单片玻璃中性层最大剪应力之间的比值。当ξ=1时夹层玻璃等效厚度与等厚度的单片... 详细信息

根据夹层复合材料弯曲理论,计算了夹层玻璃层间应力。计算夹层玻璃等效厚度时引入了剪力比系数ξ,即同样载荷条件下,夹层玻璃层间应力与同样尺寸、厚度的单片玻璃中性层最大剪应力之间的比值。当ξ=1时夹层玻璃等效厚度与等厚度的单片玻璃相等,达到承载能力上限;ξ=0时,夹层玻璃等效厚度与2片玻璃简单叠置相同,达到承载能力的下限;普通夹层玻璃等效厚度介于上限和下限之间。该文等效厚度计算结果在胶片厚度为0.38 mm时与实测值相差约0.1%。

关键词：夹层玻璃层间应力剪力比系数等效厚度

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基于BP神经网络的土壤水热动态预测模型研究

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节水灌溉 2017年第7期 11-15,27页

作者：王宏宇马娟娟孙西欢郭向红雷涛冯玚太原理工大学水利科学与工程学院太原030024

以土壤施氮量、灌水量、土壤各层初始温度、各层初始含水率以及时间作为神经网络的输入因子,以土壤温度、含水率作为输出因子,基于BP神经网络,建立了拓扑结构为17-21-14的BP-W-T预测模型,利用matlab软件对BP神经网络进行训练,并结合实... 详细信息

以土壤施氮量、灌水量、土壤各层初始温度、各层初始含水率以及时间作为神经网络的输入因子,以土壤温度、含水率作为输出因子,基于BP神经网络,建立了拓扑结构为17-21-14的BP-W-T预测模型,利用matlab软件对BP神经网络进行训练,并结合实测值对温度分布和含水率分布进行检验。结果表明:土壤温度预测模型模拟值与实测值的平均相对误差、相关系数和决定系数分别为2.28%~3.36%、0.954~0.972和0.910 2~0.944 7;含水率预测模型模拟值与实测值的平均相对误差、相关系数和决定系数分别为1.87%~3.09%、0.974 3~0.992 6和0.949 3~0.985 2;该预测模型具有较高的预测精度和良好的稳定性,可以较好地描述温度梯度下土壤水热动态变化情况,为预测土壤温度与含水率提供了一条新的途径。

关键词：温度含水率 BP神经网络水热动态

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A surface engineering strategy for the stabilization of zinc metal anodes with montmorillonite layers toward long-life rechargeable aqueous zinc ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 94-105页

作者： Wenbo Wang Ruifeng Xu Xu Zhang Peiyu Wang Bao Yang Bingjun Yang juan Yang Kailimai Su Pengjun ma Yanan Deng Xianfeng Fan Wanjun Chen Key Laboratory for Electronic materials College of Electrical Engineering Northwest Minzu University Resource Chemistry and Energy materials Research Center State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences Institute for materials and Processes School of Engineering University of Edinburgh

Rechargeable aqueous zinc-ion batteries （AZIBs） exhibit appreciable potential in the domain of electrochemical energy ***,there are serious challenges for AZIBs,for instance zinc dendrite growth,hydrogen evolution reaction （HER）,and corrosion side ***,we propose a surface engineering modification strategy for coating the montmorillonite （MMT） layer onto the surface of the Zn anode to tackle these issues,thereby achieving high cycling stability for rechargeable *** results reveal that the MMT layer on the surface of the Zn anode is able to provide ordered zincophilic channels for zinc ions migration,facilitating the reaction kinetics of zinc *** functional theory（DFT） calculations and water contact angle （CA） tests prove that MMT@Zn anode exhibits superior adsorption capacity for Zn2+and better hydrophobicity than the bare Zn anode,thereby achieving excellent cycling ***,the MMT@Zn||MMT@Zn symmetric cell holds the stable cycling over 5600 h at 0.5 ma cm-2and 0.125 m A h cm-2,even exceeding 1800 h long cycling under harsh conditions of 5 m A cm-2and 1.25 m A h *** MMT@Zn||V2O5full cell reaches over 3000 cycles at 2 A g-1with excellent rate ***,this surface engineering modification strategy for enhancing the electrochemical performance of AZIBs represents a promising application.

关键词： Surface engineering strategy Montmorillonite layer Protection mechanism of Zn anode Cycling stability Aqueous zinc ion batteries

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C反应蛋白/白蛋白比值对2型糖尿病合并急性心肌梗死患者远期不良心脑血管事件的预测价值研究

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中国全科医学 2025年第6期28卷 705-712页

作者：马娟马盛宗燕茹马学平贾绍斌宁夏医科大学总医院心血管内科宁夏回族自治区银川市750000 宁夏回族自治区人民医院妇产科宁夏回族自治区银川市750000

背景急性心肌梗死(AMI)是威胁全球公众健康的主要原因之一。虽然已有相应的再灌注治疗策略,但AMI相关的主要不良心脑血管事件(maCCEs)仍然是全世界人口死亡的原因之一。尤其合并糖尿病的AMI患者,因冠状动脉病变复杂,病变程度严重,尽早... 详细信息

背景急性心肌梗死(AMI)是威胁全球公众健康的主要原因之一。虽然已有相应的再灌注治疗策略,但AMI相关的主要不良心脑血管事件(maCCEs)仍然是全世界人口死亡的原因之一。尤其合并糖尿病的AMI患者,因冠状动脉病变复杂,病变程度严重,尽早发现和判断该部分患者远期预后相对困难,因此寻找相对简便、易获得的实验室指标,有利于为2型糖尿病(T2DM)合并AMI患者经皮冠状动脉介入(PCI)术后maCCEs的预测提供依据。目的探讨血清C反应蛋白(CRP)/白蛋白(Alb)比值(CAR)对T2DM合并AMI患者PCI术后远期maCCEs的预测价值。方法纳入2014—2019年就诊于宁夏医科大学总医院心血管内科1683例T2DM合并AMI患者为研究对象,收集患者的一般临床资料与检查结果。对所有患者进行电话或门诊随访,以全因死亡、非致死性心肌梗死、再发不稳定型心绞痛、非致死性脑卒中、新发心力衰竭或心力衰竭加重再入院、再次血运重建作为maCCEs。根据患者随访期间是否发生maCCEs分为maCCEs组(508例)和非maCCEs组(1175例)。采用单因素及多因素Logistic回归分析探讨T2DM合并AMI患者maCCEs事件的影响因素。采用Kaplan-Meier法绘制患者的生存曲线,生存曲线的比较采用Log-rank检验。采用受试者工作特征(ROC)曲线分析CAR对T2DM合并AMI患者远期发生maCCEs的预测效能,使用净重分类改善指标(NRI)和综合判别指数(IDI)评价CAR对T2DM合并AMI患者预后评估的改善效果。结果1683例患者中508例(30.18%)患者发生maCCEs。多因素Logistic回归分析显示高血压病[OR(95%CI)=1.994(1.142~3.483)]、冠状动脉植入支架长度[OR(95%CI)=1.031(1.002~1.062)]、CRP[OR(95%CI)=0.950(0.915~0.986)]、Alb[OR(95%CI)=0.933(0.880~0.989)]及CAR[OR(95%CI)=5.582(1.705~18.277)]是T2DM合并AMI患者PCI术后发生maCCEs的影响因素(PmaCCEs发生率高于CARmaCCEs的ROC曲线下面积为0.728(95%CI=0.702~0.754),最佳截断值为0.576,灵敏度为0.617,特异度为0.747。在基线模型基础上,与CRP、Alb相比,CAR能明显改善对患者发生maCCEs的预测效果(NRI=0.377,IDI=0.166,C指数=0.690;PmaCCEs发生风险的有效预测指标。

关键词：心肌梗死糖尿病,2型主要不良心脑血管事件 C反应蛋白白蛋白预测

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System Size Resonance Associated with Canard Phenomenon in a Biological Cell System

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Chinese Journal of Chemical Physics 2008年第6期21卷 521-525页

作者： juan ma hong-ying Li Zhong-huai Hou Hou-wen Xin Department of Chemical Physics University of Science and Technology of China Hefei 230026 China Hefei National Lab of Physical Science at Microscale University of Science and TechnoloEy of China Hefei 230026 China Department of Chemistry Hefei Teachers College Hefei 230000 China

The influence of internal noise on the calcium oscillations is studied. It is found that stochastic calcium oscillations occur when the internal noise is considered, while the corresponding deterministic dynamics only yields a steady state. Also,. the performance of such oscillations shows two maxima with the variation of the system size, indicating the occurrence of system size resonance. This behavior is found to be intimately connected with the canard phenomenon. Interestingly, it is also found that one of the optimal system sizes matches well with the real cell size, and such a match is robust to the variation of the control parameters.

关键词： Internal noise Calcium oscillations System size resonance Canard phenomenon

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Preparation of double-emulsion-templated microspheres with controllable porous structures by premix membrane emulsification

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Particuology 2019年第3期17卷 22-27页

作者： Xiangming Na Weiqing Zhou Tong Li Ding hong juan Li Guanghui ma State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

A scalable and versatile strategy was developed for the fabrication of uniform polymeric microspheres with controllable interconnected porous structures. Uniform water-in-oil-in-water emulsions with linear poly(methyl methacrylate-glycidyl methacrylate) in the oil phase were generated by two-step premix membrane emulsification and used for constructing the microspheres. During the emulsion solidification process, internal water droplets were packed densely together, forming a thin oil film between the internal and external water phases. After solvent diffusion, the thin film can be ruptured and pores can be templated from the internal water droplets to form interconnected porous structures. Membranes with various pore sizes were obtained. The osmotic pressure and Laplace pressure balance were used to control the porosity and pore size precisely. The proposed method enables the fabrication of functional polymeric microspheres with uniform and controllable porous structures and particle sizes. This improves their performance and broadens the scope of their applications, especially in chromatographic separation.

关键词： Double emulsion Membrane emulsification Porous microsphere Uniform structure

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