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Field-driven merging of polarizations and enhanced electrocaloric effect in BaTiO_(3)-based lead-free ceramics

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Journal of Advanced Ceramics 2022年第11期11卷 1777-1788页

作者： Xiang NIU Xiaodong JIAN Weiping GONG Wei LIANG Xuetian GONG Guangzu ZHANG Shenglin JIANG Kun YU Xiaobo ZHAO Yingbang YAO tao tao Bo LIANG Sheng-Guo LU Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter School of Materials and EnergyGuangdong University of TechnologyGuangzhou 510006China Guangdong Provincial Key Laboratory of Electronic Functional Materials and Devices Huizhou UniversityHuizhou 516007China Science and Technology on Reliability Physics and Application of Electronic Component Laboratory The 5th Electronics Research Institute of the Ministry of Industry and Information TechnologyGuangzhou 510610China Dongguan South China Design Innovation Institute Dongguan 523808China School of Optical and Electronic Information Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan 430074China

Solid-state cooling technology based on electrocaloric effect(ECE)has been advanced as an alternative to replace the vapour-compression approach to overcome the releasing of the global warming gases.However,the development in high ECE materials is still a challenge.In this work,polarization merging strategy was proposed to achieve a large ECE in xBa(Sn_(0.07)Ti_(0.93))O_(3)–(1−x)Ba(Hf_(0.1)Ti_(0.9))O_(3) ferroelectric ceramics,where x=0,0.2,0.4,0.6,0.8,and 1.Ba(Sn_(0.07)Ti_(0.93))O_(3) with an orthorhombic phase and Ba(Hf_(0.1)Ti_(0.9))O_(3) with a rhombohedral phase at room temperature were prepared beforehand as precursors,and phase-coexisted xBSnT–(1−x)BHfT ceramics were formed via a solid-state reaction approach.Phase coexisting structures were confirmed using the X-ray diffraction.The merged polarization was confirmed by the dielectric and ferroelectric properties.Optimal ECEs were obtained for 0.2BSnT–0.8BHfT ceramics,i.e.,adiabatic temperature change DT=2.16±0.08 K at 80℃and 5 MV/m,and DT=3.35±0.09 K at 80℃and 7 MV/m.

关键词： lead-free ferroelectric microstructure permittivity polarization electrocaloric effect(ECE)

基于WRF-LES模式的大气边界层近地风场精细化模拟研究

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上海交通大学学报 2024年第2期58卷 220-231页

作者：刘达琳陶韬曹勇周岱韩兆龙上海交通大学船舶海洋与建筑工程学院上海200240 安徽工程大学建筑工程学院安徽芜湖241060

台风等极端气象灾害对工程结构安全造成严重威胁,研究近地面大气边界层精细化模拟对于土木工程具有重要应用价值.数值天气预报系统(WRF)中的大涡模拟(LES)模块具有参数方案多、精度高等优点,适用于近地面风场精细化模拟,但数值天气预报... 详细信息

台风等极端气象灾害对工程结构安全造成严重威胁,研究近地面大气边界层精细化模拟对于土木工程具有重要应用价值.数值天气预报系统(WRF)中的大涡模拟(LES)模块具有参数方案多、精度高等优点,适用于近地面风场精细化模拟,但数值天气预报-大涡模拟(WRF-LES)精细化模拟效果与参数设置密切相关.寻求适用于精细化模拟近地面风场的参数设置,选用WRF-LES模式中的几种次网格模型和空间差分格式,采用较细密的网格分辨率,进行理想大气边界层模拟.对比平均风速剖面、湍流强度剖面和功率谱等风场特性,讨论关键参数对近地面风场模拟精度的影响,确定合适的参数设置.研究表明:对次网格模型,非线性回波散射和各向异性(NBA1)模型可有效改善近地面风场模拟精度;对网格方案,在计算域底部不均匀加密垂直网格可更好地描述近地面风场空间分布特征,有效减小计算资源;对空间差分格式,偶数阶差分相较奇数阶差分格式可捕获更小尺度湍流结构.所提出的WRF-LES模式参数方案,可为精细化模拟近地面风场和台风边界层提供技术参考.

关键词：次网格模型网格分辨率空间差分格式数值天气预报-大涡模拟

中药石膏药理作用研究进展与其清热物质基础探讨

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中国中药杂志 2024年第4期49卷 853-857页

作者：王陶陶杨德林韩娜殷军沈阳药科大学中药学院辽宁沈阳110016

石膏作为经典清热药物在中医药临床上有着广泛应用,但其药效物质基础与作用机制仍然存在一定争议。因此,作者综述了近年来众多学者在矿物药石膏清热效果及机制方面的研究概况以及对石膏清热的物质基础进行探讨。分别从石膏的元素组成、... 详细信息

石膏作为经典清热药物在中医药临床上有着广泛应用,但其药效物质基础与作用机制仍然存在一定争议。因此,作者综述了近年来众多学者在矿物药石膏清热效果及机制方面的研究概况以及对石膏清热的物质基础进行探讨。分别从石膏的元素组成、药效物质基础及作用机制展开介绍与探讨,发现钙离子(Ca^(2+))可能通过降低体温调节中枢钠离子/钙离子(Na^(+)/Ca^(2+))水平,从而抑制体温调定点上移;微量元素可能是通过调节免疫系统,促进Ca^(2+)的吸收以及影响前列腺素E2(prostaglandin E2,PGE2)的合成,从而抑制体温升高。作者综述了石膏的药理作用研究进展并对其清热的物质基础进行探讨,旨在进一步了解石膏清热的作用机制,为石膏的临床应用以及进一步开发提供科学依据。

关键词：石膏煅石膏物质基础作用机制

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巨噬细胞转分化在肾纤维化中的调控机制

器官移植 2024年第1期15卷 125-130页

作者：杨艳燕陶涛罗朋立青海大学高原医学研究中心高原医学教育部重点实验室青海省高原医学应用基础重点实验室(青海-犹他高原医学联合重点实验室) 西宁810001 青海大学附属医院肾内科青海省慢性肾病临床医学研究中心青海大学附属医院泌尿外科

肾纤维化是所有进展性慢性肾病发展至终末期肾病的共同病理改变。肾移植术后发生肾纤维化会严重影响移植肾功能。巨噬细胞具有高度的异质性和可塑性,在肾损伤过程中,受局部微环境刺激被募集、激活和极化,通过多种机制参与肾组织损伤、... 详细信息

肾纤维化是所有进展性慢性肾病发展至终末期肾病的共同病理改变。肾移植术后发生肾纤维化会严重影响移植肾功能。巨噬细胞具有高度的异质性和可塑性,在肾损伤过程中,受局部微环境刺激被募集、激活和极化,通过多种机制参与肾组织损伤、修复和纤维化的过程。近年来,多项研究表明,巨噬细胞可以转分化为肌成纤维细胞直接参与肾纤维化形成,这一过程被称为巨噬细胞-肌成纤维细胞转分化,但其调控机制尚不清楚。因此,本文就巨噬细胞在肾纤维化中的作用、巨噬细胞-肌成纤维细胞转分化的特点及可能的调控机制进行综述,以期为肾纤维化的相关研究提供参考。

关键词：肾纤维化巨噬细胞肌成纤维细胞肾移植慢性肾病终末期肾病转化生长因子 Smad3

Photoproducts of tetracycline and oxytetracycline involving self-sensitized oxidation in aqueous solutions:Effects of Ca^(2+) and Mg^(2+)

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Journal of Environmental Sciences 2011年第10期23卷 1634-1639页

作者： Yong Chen Hua Li Zongping Wang tao tao Chun Hu School of Environmental Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Tetracyclines constitute one of the most important antibiotic families and represent a classic example of phototoxicity. The photoproducts of tetracyclines and their parent compounds have potentially adverse effects on natural ecosystem. In this study, the self-sensitized oxidation products of tetracycline （TC） and oxytetracycline （OTC） were determined and the effects of Ca2＋ and Mg2＋on self-sensitized degradation were investigated. The Ca2＋ and Mg2＋ in the natural water sample accounted for enhancement （pH 7.3） and inhibition （pH 9.0） of photodegradation of TC and OTC due to the formation of metal-ions complexes. The formation of Mg2＋ complexes was unfavorable for the photodegradation of the tetracyclines at both pH values. In contrast, the Ca2＋ complexes facilitated the attack of singlet oxygen （102） arising from self-sensitization at pH 7.3 and enhanced TC photodegradation. For the first time, self- sensitized oxidation products of TC and OTC were verified by quenching experiments and detected by LC/ESI-DAD-MS. The products had a nominal mass 14 Da higher than the parent drugs （designated M＋ 14）, which resulted from the 102 attack of the dimethylamino group on the C-4 atom of the tetracyclines. The presence of Ca2＋ and Mg2＋ also affected the generation of M＋ 14 due to the formation of metal-ions complexes with TC and OTC. The findings suggest that the metal-ion complexation has significant impact on the self- sensitized oxidation processes and the photoproducts of tetracyclines.

关键词： tetracyclines complexation self-sensitized oxidation photoproducts

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海上风电机组支撑结构一体化设计方法

太阳能学报 2024年第6期45卷 646-651页

作者：张承婉龙凯陆飞宇张锦华陶涛新能源电力系统国家重点实验室(华北电力大学) 北京102206 北京工业大学材料与制造学部北京100124 南方电网电力科技股份有限公司广州510080

受设计工作范围分工和责任的制约,风电机组设备厂商和风电场建设单位分别设计塔筒和导管架,这种分离式设计通过塔筒底部载荷传递并反复迭代确定结构型式及尺寸。此外,现有的海上风电机组导管架设计参考海洋石油平台等规范,忽略了海上风... 详细信息

受设计工作范围分工和责任的制约,风电机组设备厂商和风电场建设单位分别设计塔筒和导管架,这种分离式设计通过塔筒底部载荷传递并反复迭代确定结构型式及尺寸。此外,现有的海上风电机组导管架设计参考海洋石油平台等规范,忽略了海上风电机组的受力特点。上述两层原因较大程度上制约了支撑结构的力学性能,且设计迭代次数较多,并无法准确获取整体结构的动态响应。为解决上述问题,提出基于拓扑优化的导管架结构设计方法,并通过改变塔筒和导管架分界面位置,即扩大拓扑优化设计空间进一步提高结构性能。选取NREL 5 MW海上风电机组为研究对象,分别对比参考结构、拓扑优化结构和一体化设计结构的固有频率和不同极限工况下的最大变形。结果证明了所提出支撑结构一体化设计方法的有效性和优越性。

关键词：海上风电机组导管架塔筒结构优化拓扑优化一体化设计

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Waste activated sludge treatment based on temperature staged and biologically phased anaerobic digestion system

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Journal of Environmental Sciences 2013年第10期25卷 2056-2064页

作者： Jingwen Yu1 Mingxia Zheng tao tao Jiane Zuo Kaijun Wang School of Environmental Science and Engineering Huazhong University of Science and Technology State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua University

The concept of temperature staged and biological phased （TSBP） was proposed to enhance the performance of waste-activated sludge anaerobic digestion. Semi-continuous experiments were used to investigate the effect of temperature （35 to 70℃） as well as the hydraulic retention time （HRT）（2, 4 and 6 days） on the acidogenic phase. The results showed that the solubilization degree of waste- activated sludge increased from 14.7% to 30.1% with temperature increasing from 35 to 70℃, while the acidification degree was highest at 45℃ （17.6%）, and this was quite different from the temperature impact on hydrolysis. Compared with HRT of 2 and 6 days, 4 days was chosen as the appropriate HRT because of its relatively high solubilization degree （24.6%） and acidification degree （20.1%） at 45℃. The TSBP system combined the acidogenic reactor （45℃, 4 days） with the methanogenic reactor （35℃, 16 days） and the results showed 84.8% and 11.4% higher methane yield and volatile solid reduction, respectively, compared with that of the single-stage anaerobic digestion system with HRT of 20 days at 35℃. Moreover, different microbial morphologies were observed in the acidogenic- and methanogenic-phase reactors, which resulted from the temperature control and HRT adjustment. All the above results indicated that 45℃ was the optimum temperature to inhibit the activity of methanogenic bacteria in the acidogenic phase, and temperature staging and phase separation was thus accomplished. The advantages of the TSBP process were also confirmed by a full-scale waste-activated sludge anaerobic digestion project which was an energy self-sufficient system.

关键词： temperature-staged and biologically-phased acidogenic and methanogenic phases temperature hydraulic retention time

Long-term outcomes of high-risk elderly male patients with multivessel coronary disease： optimal medical therapy versus revascularization

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老年心脏病学杂志：英文版 2016年第2期13卷 152-157页

作者： tao tao Hao WANG Shu-Xia WANG Yu-tao GUO Ping ZHU Yu-Tang WANG First Geriatric Cardiology Division Chinese PLA General Hospital Beijing China

BackgroundMany 研究显示了那医药治疗和经皮的冠的干预与稳定的冠的动脉疾病以病人的长期的预后有类似的效果。这研究与高风险的 angina.MethodsIn 在老病人调查了最佳的医药治疗(OMT ) 和 revascularization-plus-OMT 的效果这未来的... 详细信息

BackgroundMany 研究显示了那医药治疗和经皮的冠的干预与稳定的冠的动脉疾病以病人的长期的预后有类似的效果。这研究与高风险的 angina.MethodsIn 在老病人调查了最佳的医药治疗(OMT ) 和 revascularization-plus-OMT 的效果这未来的非使随机化的研究，有 angiographically 证实的 multivessel 疾病的 241 个连续高风险的老男病人(65-92 岁) 从 2004 年 1 月在登记被注册到 2005 年4月。这些， 98 个病人经历了 OMT ， 143 加后续的 OMT.ResultsAfter 6.5 年经历了 revascularization 治疗，我们发现长期的心脏的死亡的率在比在经历了 revascularization 的那些经历了 OMT 的病人是显著地更高的(6.5年的 unadjusted 死亡率，14.3%为 OMT 对7.0%为 revascularization 病人；木头等级 P = 0.04 ) 。然而，主要不利心脏的脑血管的事件(MACCE ) 的全面风险在所有病人之中是类似的(6.5 年的 unadjusted 死亡率， 29.6% 为 OMT 对 27.3% 为 revascularization 病人；木头等级 P = 0.67 ).ConclusionsOMT 与心脏的死亡的增加被联系但是 MACCE 的类似的 6.5 年的风险与在有冠的 multivessel 的高风险的老男病人的 revascularization 相比疾病。

关键词：药物治疗血管病变冠状动脉患者老年男性预后 OMT

Photolysis of chlortetracycline in aqueous solution:Kinetics,toxicity and products

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Journal of Environmental Sciences 2012年第2期24卷 254-260页

作者： Yong Chen Hua Li Zongping Wang tao tao Dongbin Wei Chun Hu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China School of Environmental Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China.

The aqueous photodegradation of the widely used antibiotic chlortetracycline（CTC） was investigated under simulated sunlight.The quantum yield of photodegradation increased from 3.3 × 10-4 to 8.5 × 10-3 within the pH range of 6.0 to 9.0.The presence of Ca2＋,Fe3＋,and NO3-enhanced the photodegradation of CTC,whereas Mg2＋,Mn2＋,and Zn2＋ inhibited the degradation with the order Mn2＋ Zn2＋ Mg2＋ at pH 7.3.The monovalent cations（Na＋ and K＋） had negligible effect on the photolysis of CTC.Fulvic acid（FA） decreased the photodegradation of CTC due to light screening effect.Hydrogen peroxide（H2O2） was formed concurrently with direct photodegradation of CTC.The generation rate of H2O2 increased from 0.027 to 0.086 μmol/（L.min） when the pH ranged from 6.0 to 9.0.The CTC solution was about three-fold more toxic to the Photobacterium phosphoreum bacteria after irradiation,suggesting that the photoproducts and H2O2 formed in the CTC solution exhibited high risk on the bacteria.By LC-ESI（＋）-MS,the photoproducts of CTC were identified.The direct photodegradation of CTC was involved in hydroxylation and N-demethyl/dedismethyl processes.The main photoproducts included the iso-CTC analog containing hydroxyl groups（m/z 511.4 and 495.4）,and the N-demethyl/dedismethyl products of the photoproduct m/z 495.4（m/z 481.3 and 467.4）.In addition,the photochemical dechlorination of CTC led to tetracycline（m/z 445.5）.

关键词： chlortetracycline direct photodegradation phototoxicity photoproducts