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Engineering FeOOH/Ni(OH)_(2) heterostructures on Ni_(3)S_(2)surface to enhance seawater splitting

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Rare Metals 2024年第5期43卷 1989-1998页

作者： Chen yang ya-dong li li-Juan Cao Xi-Long Wang Han-Pu liang Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Sino-Danish College University of Chinese Academy of SciencesBeijing 100049China

The construction of highly stable and efficient electrocatalysts is desirable for seawater splitting but remains challenging due to the high concentration of Cl-in ***,FeOOH/Ni(OH)_(2)heterostructure supported on Ni_(3)S_(2)-covered nickel foam(Fe–Ni/Ni_(3)S_(2)/NF)was fabricated by hydrothermal and etching methods,as well as anodic oxidation *** electronic structure of FeOOH and Ni(OH)_(2)could be modulated after depositing FeOOH nanoparticles on Ni(OH)_(2)nanosheet,which greatly boosted the catalytic *** the catalyst used as an electrode for oxygen evolution reaction(OER),it needed low overpotentials of 266 and 368 m V to achieve current densities of 100 and 800 m A·cm^(-2),respectively,in 1 mol·L^(-1)KOH+seawater *** can operate continuously at 100 m A·cm^(-2)for 400 h without obvious ***,in situ generated SO_(4)^(2-)from inner Ni_(3)S_(2)during electrolysis process would accumulate on the surface of active sites to form passivation layers to repel Cl^(-),which seemed to be responsible for superior *** study not only synthesizes an OER catalyst for highly selective and stable seawater splitting,but also gives a novel approach for industrial hydrogen production.

关键词： Anodic oxidation Heterostructure Oxygen evolution reaction Seawater splitting

Dielectric Constant Calculation of Poly(vinylidene fluoride)Based on Finite Field and Density Functional Theory

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Chinese Journal of Polymer Science 2024年第5期42卷 655-662,I0009页

作者： Yong-Zhi lin Lu-Kun Feng ya-dong li Chao-Fan Chang Cai-Zhen Zhu Ming-liang Wang Jian Xu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen518055China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu610041China

In this study,we proposed a novel method that integrates density functional theory(DFT)with the finite field method to accurately estimate the polarizability and dielectric constant of *** approach effectively accounts for the influence of electronic and geometric conformation changed on the dielectric *** validated our method using polyethylene(PE)and polytetrafluoroethylene(PTFE)as benchmark materials,and found that it reliably predicted their dielectric ***,we explored the impact of conformation variations in poly(vinylidene fluoride)(PVDF)on its dielectric constant and *** resulting dielectric constants ofα-andγ-PVDF(3.0)showed excellent agreement with crystalline PVDF in *** findings illuminate the relationship between PVDF’s structural properties and its electrical behavior,offering valuable insights for material design and applications.

关键词： Dielectric constant PVDF Finite field DFT

Molecular Chain Flexibility and Dielectric Loss at High-Frequency:Impact of Ester Bond Arrangement in Poly(ester imide)s

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Chinese Journal of Polymer Science 2024年第8期42卷 1122-1133页

作者： ya-dong li Hong li Lu-Kun Feng Feng Bao Ming-liang Wang Cai-Zhen Zhu Zhao-Hui Zheng Xiao-Bin Ding Jian Xu Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China University of Chinese Academy of Sciences Beijing 100081China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China

The evolution of high-frequency communication has accentuated the significance of controlling dielectric properties in polymer ***,it has been theorized that rigid molecular chains lead to lower dielectric ***,the validity of this proposition at high frequencies remains *** scrutinize the correlation between chain flexibility and dielectric properties,we synthesized six poly(ester imide)s(PEIs)with systematically varied molecular chain flexibilities by modifying the ester's substitution on the aromatic *** introduction of ester bonds bestowed all PEI films with a low dielectric dissipation factor(D_(f)),ranging from 0.0021 to 0.0038 at 10 GHz in dry *** dry D_(f)displayed a pattern consistent with volume polarizability(P/V).Unexpectedly,PI-mmm-T,featu ring the most flexible molecular chain,exhibited the lowest dielectric loss under both dry(0.0021@10 GHz)and hygroscopic(0.0029@10 GHz)***,the observed increase in D_(f)after humidity absorption suggests that the high dielectric loss of PEI in applications may be attributed to its hygroscopic *** simulations and characterization of the aggregation structure revealed that the smaller cavities within flexible molecular chains,after close stacking,impede the entry of water *** sacrificing high-temperature resistance,the precursor exhibited enhanced solubility properties and could be processed into high-quality *** research unveils new insights into the relationship between flexibility and highfrequency dielectric loss,offering innovative perspectives on synthesizing aromatic polymers with exceptional dielectric properties.

关键词： 5G communications Poly(ester imide)s Molecular chain flexibility Dielectric properties Humidity absorption

基于路径概率的桥梁全寿命成本计算方法及例证

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公路交通科技 2024年第6期41卷 101-108页

作者：王崇交姚昌荣赵思光徐川李亚东四川路桥建设集团股份有限公司四川成都610041 西南交通大学土木工程学院四川成都610031

为解决传统桥梁全寿命设计方法在工程实践中遇到的设计概念模糊、计算方法不明确及与相关规范脱节的不足,以提高公共安全与交通舒适度,降低建造和运营综合成本,提出了基于路径概率并与可靠度结合的混凝土桥梁全寿命成本计算方法。首先,... 详细信息

为解决传统桥梁全寿命设计方法在工程实践中遇到的设计概念模糊、计算方法不明确及与相关规范脱节的不足,以提高公共安全与交通舒适度,降低建造和运营综合成本,提出了基于路径概率并与可靠度结合的混凝土桥梁全寿命成本计算方法。首先,在深入研究桥梁全寿命设计的基础上,依据调研所得桥梁管养投入实际数据,拟合了不同服役地区不同桥梁等级的检测成本计算公式,以及不同公路等级不同养修成本的养修成本取值区间,以此构建了桥梁全寿命成本计算基准。其次,以钢筋在氯离子侵蚀和碳化耦合作用下的锈胀开裂模型为基础,采用路径概率方法构建了桥梁全寿命养修概率模型。然后,通过蒙特卡洛法进行求解,并将养修方案、养修成本通过可靠度指标联系起来,结合规范中关于正常使用极限状态指标的相关规定,提出基于可靠度的全寿命成本计算方法。最后,采用所提方法计算了不同桥梁设计方案在设计使用寿命期内的养修概率,综合建造成本、检测成本和养修成本估算全寿命成本及其对应的可靠度。结果表明:不同可靠度指标的取值对设计方案的全寿命成本有显著影响,随着可靠度指标的提高不同设计方案的经济性均出现先上升后下降的趋势。因此,设计过程目标可靠度的取值不宜过大,可通过一个较低的可靠度指标,适当放宽耐久性设计准入,以允许桥梁在使用过程出现一定的耐久性问题,并通过后续养修进行矫正,这样对于全寿命成本而言,更具有经济性。

关键词：桥梁工程全寿命成本计算方法路径概率模型全寿命设计方法全寿命成本分析可靠度

Uniform Rice-like CdS Particles Prepared from Water-in-oil Microemulsions

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Chemical Research in Chinese Universities 2006年第1期22卷 11-13页

作者： ZHOU Hai-cheng XU Sheng PENG Qing li ya-dong The Key Laboratory of Atomic ＆ Molecular Nanosciences of the Ministry of Education Department of ChemistryTsinghua UniversityBeijing100084P.R.China Department of Chemistry and Engineering Shandong University of Technology Zibo 255000 P. R. China

Uniform rice-like CdS particles were synthesized in cyclohexane/Triton X-100/n-pentanol/water quaternary microemulsions. The as-prepared samples were characterized by X-ray diffraction, transmission electron microscopy, and electron diffraction. The results indicate that the size and the shape of the rice-like CdS particles can be influenced by the molar ratio of water to the surfactant（w value） and the reactant concentrations.

关键词： W/O microemulsion Rice-like CdS nanoparticle Value of w Morphology

自体牙骨移植材料修复牙槽骨缺损的应用效果研究

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中国实用口腔科杂志 2024年第1期17卷 74-79页

作者：郭子君丁铭李雅冬中国人民解放军陆军特色医学中心口腔科重庆400042 重庆医科大学附属第一医院口腔科重庆400042

目的研究自体牙骨移植材料结合引导骨再生术(guided bone regeneration,GBR)在修复牙槽骨缺损中的临床效果。方法选择2020年1月至2021年10月于重庆医科大学附属第一医院口腔科就诊的需行GBR修复牙槽骨缺损的患者82例。依照随机数表法... 详细信息

目的研究自体牙骨移植材料结合引导骨再生术(guided bone regeneration,GBR)在修复牙槽骨缺损中的临床效果。方法选择2020年1月至2021年10月于重庆医科大学附属第一医院口腔科就诊的需行GBR修复牙槽骨缺损的患者82例。依照随机数表法分为研究组(42例)和对照组(40例)。研究组患者在种植术中将自体牙骨移植材料植入牙槽骨缺损处,对照组患者在种植术中将Bio-Oss?骨粉植入牙槽骨缺损处。比较两组患者的种植成功率、骨组织指标(颊舌侧骨板宽度、边缘骨吸收量)、种植体稳定性值(implant stability quotient,ISQ)及不良反应发生率。结果术后1年研究组和对照组患者种植成功率的比较,差异无统计学意义(χ^(2)=0.186,P=0.735);两组患者术前及术后即刻的颊舌侧骨板宽度比较,差异均无统计学意义(均P> 0.05);研究组术后12个月的颊舌侧骨板宽度大于对照组,差异有统计学意义(t=3.872,P=0.005);研究组术后12个月的边缘骨吸收量低于对照组,差异有统计学意义(t=-3.030,P=0.039);术后6个月研究组ISQ高于对照组,差异有统计学意义(t=2.996,P=0.017);两组不良反应发生率的比较,差异无统计学意义(χ^(2)=0.076,P=0.532)。结论自体牙骨移植材料与Bio-Oss?骨粉修复牙槽骨缺损均能获得较高的治疗成功率。相比Bio-Oss?骨粉,自体牙骨移植材料能有效增加术后牙槽骨宽度,延缓种植体边缘骨吸收,获得更好的种植体稳定性,具有较高的生物安全性,值得在临床上进一步推广。

关键词：自体牙骨移植材料口腔种植临床效果

Web Page Forensics:A Web Spider Based Approach

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Journal of Harbin Institute of Technology(New Series) 2014年第6期21卷 46-50页

作者： ya-dong li dong-Hui Hu Yu-Qi Fan Xin-dong Wu School of Computer and Information Hefei University of Technology Dept.of Computer Science University of VermontBurlingtonVT 05405USA

Cyber-crimes are growing rapidly,so it is important to obtain the digital evidence on the web ***,people can examine the browser history on the client side and data files on the server side,but both of them have shortcomings in real criminal *** overcome the weakness,this paper designs a web page forensic scheme to snapshot the pages from web servers with the help of web ***,it designs several steps to improve the trustworthiness of these *** the pages will be dumped in local database which can be presented as reliable evidence on the court.

关键词： web page digital forensics web spider

关于消防水泵控制柜多线控制盘启动控制原理的研究

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建筑技术开发 2024年第3期51卷 123-125页

作者：李亚东刘伟王嘉豪廊坊新奥房地产开发有限公司河北廊坊065001 中国建筑一局(集团)有限公司河北廊坊065001

消防水泵的启动分为手动、自动,其中消防控制室火灾报警控制器的手动控制分为总线控制盘启动和多线控制盘启动。目前消防水泵控制柜关于多线控制盘手动启/停消防水泵的二次控制回路,不管是相关图集以及不同厂家的产品均存在不同的做法... 详细信息

消防水泵的启动分为手动、自动,其中消防控制室火灾报警控制器的手动控制分为总线控制盘启动和多线控制盘启动。目前消防水泵控制柜关于多线控制盘手动启/停消防水泵的二次控制回路,不管是相关图集以及不同厂家的产品均存在不同的做法和差异。研究就相关规范、图集为依据针对消防水泵控制柜的二次控制原理进行分析,并对工程实践提出参考建议,以达到消防水泵控制的合理性和安全性。

关键词：消防水泵控制柜手动启动多线控制盘直启

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石灰和粉煤灰固化软土静动力力学特性研究

广州建筑 2024年第7期52卷 44-48页

作者：杨克政李亚东王一兆广州大学土木工程学院广州510006 广州市设计研究院广州510620

软土广泛存在于华南沿海地区,常使用固化剂对其进行固化,但在现有的研究中,缺少对其固化前后静、动力力学性能的研究,也鲜有探究各关键因素间的相互联系。因此,本文通过一系列固结不排水三轴试验,研究分析了粉煤灰和石灰掺水泥比(TR)、... 详细信息

软土广泛存在于华南沿海地区,常使用固化剂对其进行固化,但在现有的研究中,缺少对其固化前后静、动力力学性能的研究,也鲜有探究各关键因素间的相互联系。因此,本文通过一系列固结不排水三轴试验,研究分析了粉煤灰和石灰掺水泥比(TR)、固化比(CR)、含水率(w)和围压(σ’3)对软土和固化软土的静、动力力学特性的影响。试验表明:固化土的静力特性随TR的增加而先增加后降低,随围压的增加而增加,随含水率的增加而减少;固化土的动弹性模量随CR和围压的增加而增加,随含水率的增大而减小;固化土的阻尼比则随CR和围压的增加而减少,随含水率的增大而增大。本文的研究结果,为今后的软土固化研究提供了理论基础。

关键词：土力学静三轴试验动三轴试验动弹性模量