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Graphitic carbon nitride (g-C3N4)-based nanosized heteroarrays: Promising materials for photoelectrochemical water splitting

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Carbon Energy 2020年第2期2卷 223-250页

作者： Liqun Wang Wenping Si yueyu Tong Feng hou Daniele Pergolesi Jungang hou thomas Lippert Shi Xue Dou Ji Liang Applied Physics Department College of Physics and Materials ScienceTianjin Normal UniversityTianjinChina Key Laboratory of Advanced Ceramics and Machining Technology Ministry of EducationSchool of Materials Science and EngineeringTianjin UniversityTianjinChina Institute for Superconducting and Electronic Materials Australian Institute of Innovative MaterialsUniversity of WollongongNorth WollongongNSWAustralia Laboratory for Multiscale Materials Experiments Paul Scherrer InstituteVilligenPSISwitzerland State Key Laboratory of Fine Chemicals DUT-KTH Joint Education and Research Center on Molecular DevicesInstitute of Energy Science and TechnologyDalian University of Technology(DUT)DalianChina

Photoelectrochemical(PEC)water splitting is recognized as a sustainable strategy for hydrogen generation due to its abundant hydrogen source,utilization of inexhaustible solar energy,high-purity product,and environment-friendly *** actualize a practical PEC water splitting,it is paramount to develop efficient,stable,safe,and low-cost photoelectrode ***,graphitic carbon nitride(g-C3N4)has aroused a great interest in the new generation photoelectrode materials because of its unique features,such as suitable band structure for water splitting,a certain range of visible light absorption,nontoxicity,and good *** inherent defects of g-C3N4,however,seriously impair further improvement on PEC performance,including low electronic conductivity,high recombination rate of photogenerated charges,and limited visible light absorption at long wavelength *** of g-C3N4-based nanosized heteroarrays as photoelectrodes has been regarded as a promising strategy to circumvent these inherent limitations and achieve the high-performance PEC water splitting due to the accelerated exciton separation and the reduced combination of photogenerated electrons/***,we summarize in detail the latest progress of g-C3N4-based nanosized heteroarrays in PEC water-splitting ***,the unique advantages of this type of photoelectrodes,including the highly ordered nanoarray architectures and the heterojunctions,are ***,different g-C3N4-based nanosized heteroarrays are comprehensively discussed,in terms of their fabrication methods,PEC capacities,and mechanisms,*** conclude,the key challenges and possible solutions for future development on g-C3N4-based nanosized heteroarray photoelectrodes are discussed.

关键词： graphitic carbon nitride heterojunctions nanoarrays photoelectrochemical water splitting

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旋转防喷器外壳体的有限元分析与优化设计

机电产品开发与创新 2024年第2期37卷 6-10页

作者：田海疆 Ismail SAAD yOONG hou Pin 王翠凤福建信息职业技术学院智能制造学院福建福州350003 沙巴大学工程学院马来西亚沙巴州亚庇马来西亚88670

针对国外生产的一款旋转防喷器,使用三维造型软件中望3D建立该型号旋转防喷器的三维实体模型;将底座外壳体三维实体模型导入ANSyS软件中,通过有限元分析,求解出了外壳体的应力强度分布情况,设定两条路径分别进行等效线性化,获得了两条... 详细信息

针对国外生产的一款旋转防喷器,使用三维造型软件中望3D建立该型号旋转防喷器的三维实体模型;将底座外壳体三维实体模型导入ANSyS软件中,通过有限元分析,求解出了外壳体的应力强度分布情况,设定两条路径分别进行等效线性化,获得了两条路径上的一次整体薄膜应力、一次局部薄膜应力、一次弯曲应力、二次应力和峰值应力,校核了旋转防喷器底座外壳体的强度;通过ANSyS WorkBench仿真平台对底座外壳体进行了优化设计,获得了底座外壳体的优化参数。

关键词：旋转防喷器有限元分析优化设计 ANSyS

A 3D Numerical Method for Studying Vortex Formation Behind a Moving Plate

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Communications in Computational Physics 2006年第2期1卷 207-228页

作者： T.y.hou V.G.Stredie T.y.Wu Department of Applied and Computational Mathematics California Institute of TechnologyPasadenaCA 91125USA Department of Mechanical Engineering California Institute of TechnologyPasadenaCA 91125USA

In this paper,we introduce a three-dimensional numerical method for computing the wake behind a flat plate advancing perpendicular to the *** numerical method is inspired by the panel method of *** and ***[*** and ***,Low-speed Aerodynamics,2001]and the 2D vortex blob method of Krasny[***,Lectures in ***.,28(1991),pp.385–402].The accuracy of the method will be demonstrated by comparing the 3D computation at the center section of a very high aspect ratio plate with the corresponding two-dimensional ***,we compare the numerical results obtained by our 3D numerical method with the corresponding experimental results obtained recently by Ringuette[***,***,2004]in the towing *** numerical results are shown to be in excellent agreement with the experimental results up to the so-called formation time.

关键词： Aerodynamics vortex dynamics potential flows

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湘东北地区早寒武世石煤沉积物源区研究

煤炭科学技术 2024年第3期52卷 169-179页

作者：张卫国侯恩科李焕同周佳瑞杨佳美西安科技大学地质与环境学院陕西西安710054 自然资源部煤炭资源勘查与综合利用重点实验室陕西西安710021 陕西省煤炭绿色开发地质保障重点实验室陕西西安710054

湘东北地区早寒武世石煤中伴生有多种高含量元素,属性特征鲜明。为查明该区石煤的沉积物来源,从石煤元素地球化学角度入手,利用X射线荧光光谱仪(XRF)、电感耦合等离子质谱仪(ICP–MS)分别测定了研究区12个石煤样品的常量元素和微量元素... 详细信息

湘东北地区早寒武世石煤中伴生有多种高含量元素,属性特征鲜明。为查明该区石煤的沉积物来源,从石煤元素地球化学角度入手,利用X射线荧光光谱仪(XRF)、电感耦合等离子质谱仪(ICP–MS)分别测定了研究区12个石煤样品的常量元素和微量元素含量。根据石煤中常量元素组合关系、微量元素含量特征、稀土元素分布特征及相关元素地球化学参数,探讨了湘东北地区早寒武世石煤的沉积物源区。结果表明:湘东北地区早寒武世石煤以无机矿物质为主要组成部分,石煤中SiO_(2)含量占比最高,SiO_(2)与其他常量元素(及其他常量元素之间)关系不明显,石英矿物形态具有陆源输入特征;石煤中微量元素(V,As,Sr,Mo,Cd,Sb,Ba,Bi,U)具有明显富集特征,稀土元素分布特征和Nb/y–Zr/TiO_(2)关系表明石煤受到了中性岩影响,LaN/ybN表明石煤沉积物沉积速率自东南向西北有减小趋势,即物源来自东部和南部方向;w(SiO_(2))/w(Al_(2)O_(3)),w(Al_(2)O_(3))/w(Al_(2)O_(3)+Fe_(2)O_(3)),w(Al)/w(Al+Fe+Mn)和K_(2)O/Na_(2)O–SiO_(2)构造判别模型显示早寒武世石煤沉积于大陆边缘区域,主要接受陆源输入。通过与研究区东南方向分布的上墅群中酸性岩中稀土元素、Rb、Nb、Pb含量以及双溪坞群出露的岩浆岩中常量元素含量及组合特征综合比较,并结合江南造山带的演化历史,认为江南造山带东南缘发育的中、酸性岩带为湘东北地区早寒武世石煤沉积物源区,亦是石煤富集微量元素的主控因素之一。

关键词：湘东北石煤元素地球化学物源

肝细胞癌酸性微环境下免疫细胞的作用和机制的研究进展

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中华肝胆外科杂志 2024年第5期30卷 386-390页

作者：侯应健王博石柳又祎金成江南大学附属医院肝胆外科无锡214122 江南大学无锡医学院无锡214122

原发性肝癌形成和进展过程中,逐渐酸化的肿瘤微环境发挥着关键作用。免疫细胞在酸性微环境调控下,分化与功能向免疫抑制发生转变,进一步导致了肝癌免疫逃逸。本文就肝细胞癌肿瘤酸性微环境的形成、酸性微环境下各类免疫细胞的变化及其... 详细信息

原发性肝癌形成和进展过程中,逐渐酸化的肿瘤微环境发挥着关键作用。免疫细胞在酸性微环境调控下,分化与功能向免疫抑制发生转变,进一步导致了肝癌免疫逃逸。本文就肝细胞癌肿瘤酸性微环境的形成、酸性微环境下各类免疫细胞的变化及其对肝细胞癌发生发展的作用和其机制进行综述,旨在为肝细胞癌免疫治疗研究提供新思路。

关键词：癌,肝细胞肿瘤微环境肿瘤逃逸免疫疗法免疫细胞

The hepatitis B vaccine originally jointly developed by China and the US is safe and effective

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Science China(Life Sciences) 2014年第5期57卷 549-550页

作者： hou yunDe National Institute of Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention

According to the disease control and prevention data of China,hepatitis B vaccinations have caused 188 coincidence deaths of newborns totally from 2000 to *** problems have been found with the *** inspection of the manufacturers,all vaccines are launched to the market after inspection of the central government of *** events happened also in other *** recent deaths related to hepatitis B vaccination have been proved to be *** hepatitis B virus vaccine used is originally jointly developed by the Chinese government and the US *** safety has been proved by the inoculation of one billion people around the globe.

关键词：乙肝疫苗美国政府安全性中国疫苗接种疾病控制中央政府病毒疫苗

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雪层杜鹃中的黄酮类化合物及其抗氧化和抗炎活性研究

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天然产物研究与开发 2024年第8期36卷 1350-1356页

作者：王兰曾禧姚后宗袁涛江西师范大学健康学院南昌330022 江西师范大学生命科学学院南昌330022

本文研究雪层杜鹃提取物中的黄酮类化学成分及其抗氧化和抗炎活性。本研究采用硅胶柱色谱、Sephadex LH-20柱色谱和半制备高效液相色谱(HPLC)等多种色谱分离技术对雪层杜鹃的乙酸乙酯提取物进行分离纯化,并通过NMR、IR和HR-ESI-MS等方... 详细信息

本文研究雪层杜鹃提取物中的黄酮类化学成分及其抗氧化和抗炎活性。本研究采用硅胶柱色谱、Sephadex LH-20柱色谱和半制备高效液相色谱(HPLC)等多种色谱分离技术对雪层杜鹃的乙酸乙酯提取物进行分离纯化,并通过NMR、IR和HR-ESI-MS等方法共鉴定出8个黄酮类化合物,包括1个新化合物:3′,8-二甲氧基槲皮素-3-O-α-L-阿拉伯呋喃糖苷(1)和7个已知化合物:桑黄素-3-O-β-L-赖氧苷(2)、花旗松素-3-O-α-L-阿拉伯糖苷(3)、表儿茶素(4)、(–)-表没食子儿茶素(5)、(–)-儿茶素(6)、二氢杨梅素(7)、二氢槲皮素(8)。它们的抗氧化和抗炎活性利用H_(2)O_(2)氧化损伤模型和脂多糖诱导的一氧化氮生成模型分别测定。化合物2、4和8使H_(2)O_(2)损伤的SH-Sy5y细胞存活率从(44.0±2.3)%分别提高到了(80.6±0.4)%、(78.4±1.6)%和(81.9±1.7)%。化合物8也表现出一定的抗炎活性,IC_(50)值为37.7μmol/L。结果证明雪层杜鹃中的黄酮类化合物具有被发掘成抗氧化和抗炎先导化合物的潜力。

关键词：雪层杜鹃类黄酮抗炎活性抗氧化活性

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数字经济赋能皮革制造业转型升级研究

中国皮革 2024年第1期53卷 63-66,70页

作者：侯玉荣西安欧亚学院陕西西安710065

在皮革产业高速发展的背景下,皮革制造业转型升级成为产业发展需要关注的重点问题。借助数字经济支撑,推动皮革制造业向服务型、高质量和创新方向发展,是制造业转型发展的基本方向。单纯依赖传统技术体系和生产管理模式,必然无法满足皮... 详细信息

在皮革产业高速发展的背景下,皮革制造业转型升级成为产业发展需要关注的重点问题。借助数字经济支撑,推动皮革制造业向服务型、高质量和创新方向发展,是制造业转型发展的基本方向。单纯依赖传统技术体系和生产管理模式,必然无法满足皮革制造业转型升级要求。以数字经济为导向,构建智能化协同运行体系,是皮革制造业转型升级的根本力量。本文在明确皮革制造业转型升级方向与内容的基础上,分析数字经济赋能皮革制造业转型升级的作用路径和作用机制,探索皮革制造业转型升级创新模式,为皮革制造业企业转型发展提供参考。

关键词：皮革制造业数字经济转型升级

Content sensitivity based access control framework for Hadoop

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Digital Communications and Networks 2017年第4期3卷 213-225页

作者： Ashwin Kumar T.K. Hong Liu Johnson P. thomas Xiaofeh hou Department of Computer Science Oklahoma State University Stillwater OK USA

Big data technologies have seen tremendous growth in recent years. They are widely used in both industry and academia. In spite of such exponential growth, these technologies lack adequate measures to protect data from misnse/abuse. Corporations that collect data from multiple sources are at risk of liabilities due to the exposure of sensitive information. In the current implementation of Hadoop, only file-level access control is feasible. Providing users with the ability to access data based on the attlibutes in a dataset or the user＇s role is complicated because of the sheer volume and multiple formats （structured, unstructured and semi-structured） of data. In this paper, we propose an access control framework, which enforces access control policies dynamically based on the sensitivity of the data. This framework enforces access control policies by harnessing the data context, usage patterns and informat/on sensitivity. Information sensitivity changes over time with the addition and removal of datasets, which can lead to modifications in access control decisions. The proposed framework accommodates these changes. The proposed framework is automated to a large extent as the data itself determines the sensitivity with minimal user intervention. Our experimental results show that the proposed framework is capable of enforcing access control policies on non-multimedia datasets with minimal overhead.

关键词： Access control Data driven information sensitivity Privacy Information value