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Fluorescence-based quantitative characterization of structural phase transitions in Li^(+)/Er^(3+):BaTiO_(3)ferroelectric ceramics

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Journal of Materials Science & Technology 2021年第33期92卷 143-147页

作者： Jiaming Li Enwei Sun Yaping Ma huashan Zheng Hua Zhao Zhiguo zhang School of Physics Harbin Institute of TechnologyHarbin 150001China Condensed Matter Science and Technology Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin 150080China School of Materials and Engineering Harbin Institute of TechnologyHarbin 150001China

We propose a method to quantitatively characterize the fine phase transition processes of Li^(+)/Er^(3+):BaTiO_(3)(BLET)ferroelectric materials by observing fluorescence wavelength shift.A lithium and erbium co-doped barium titanate ferroelectric ceramic was fabricated and the down-conversion infrared fluorescence spectra of the transition^(4)I13/2→^(4)I15/2 were measured as a function of *** three structural phase transition processes,namely rhombohedral-orthorhombic,orthorhombic-tetragonal,and tetragonal-cubic transformations,determined by X-ray diffraction results are accompanied by corresponding changes in the position of the fluorescence peaks,yielding an exact *** contactless,non-destructive and spatially-resolved fluorescence method provides a localized quantitative analysis for the phase transition processes of BLET *** this method is based on the fluorescence peak wavelength dependence on the crystal environment,it may potentially be used to characterize the phase transitions in other ferroelectric materials.

关键词： Ferroelectrics Phase transition Fluorescence X-ray diffraction

Comprehensive optimization of piezoelectric coefficient and depolarization temperature in Mn-doped Bi_(0.5)Na_(0.5)TiO_(3)-Bi_(0.5)K_(0.5)TiO_(3)-BaTiO_(3)lead-free piezoceramics

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Journal of Materials Science & Technology 2024年第5期172卷 255-263页

作者： huashan Zheng Enwei Sun Huajie Luo Xiaoyu zhang Yixiao Yang Bin Yang Rui zhang Shantao zhang Wenwu Cao Condensed Matter Science and Technology Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin150080China Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing100083China National Laboratory of Solid State Microstructures Department of Materials Science and EngineeringCollege of Engineering and Applied Science&Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China Department of Mathematics and Materials Research Institute The Pennsylvania State UniversityUniversity ParkPennsylvania16802United States of America

Lead-free Bi_(_(0.5))Na_(_(0.5))TiO_(3)(BNT)piezoelectric ceramics have the advantages of large coercive fields and high Curie *** the improvement of piezoelectric coefficient(d 33)is usually accompanied by a huge sacrifice of depolarization temperature(T d).In this work,a well-balanced performance of d 33 and T d is achieved in MnO_(2)-doped 0.79(Bi_(_(0.5))Na_(_(0.5))TiO_(3))-0.14(Bi_(0.5)K_(0.5)TiO_(3))-0.07BaTiO_(3)ternary *** in-corporation of 0.25 mol%MnO_(2)enhances the d 33 by more than 40%,while T d remains almost unchanged(i.e.,d 33=181 pC/N,T d=184℃).X-ray diffraction(XRD)shows that an appropriate fraction of the small axis-ratio ferroelectric phase(pseudo-cubic,P c)coexists with the long-range ferroelectric phase(tetrag-onal,T)under this MnO_(2)*** force microscopy(PFM)has revealed a special domain configuration,namely large striped and layered macro domains embedded with small *** study provides a distinctive avenue to design BNT-based piezoelectric ceramics with high piezoelectric performance and temperature stability.

关键词： BNT-BKT-BT ceramics Mn doping Piezoelectric Depolarization temperature Phase structure

间(对)甲酰基偶氮氯膦的合成及其与稀土元素显色反应的研究

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化学试剂 1982年第1期 1-4页

作者：张华山陈震华曾云鹗武汉大学化学系

变色酸双偶氮衍生物是一类重要的显色剂,常用于稀土、碱土和铀钍的测定。自偶氮胂M和偶氮硝羧合成以后,不对称变色酸双偶氮衍生物的研究与应用发展很快。1974年,我们合成了甲酰基、乙酰基、丙酰基偶氮羧等不对称变色酸双偶氮衍生物。实... 详细信息

变色酸双偶氮衍生物是一类重要的显色剂,常用于稀土、碱土和铀钍的测定。自偶氮胂M和偶氮硝羧合成以后,不对称变色酸双偶氮衍生物的研究与应用发展很快。1974年,我们合成了甲酰基、乙酰基、丙酰基偶氮羧等不对称变色酸双偶氮衍生物。实验证明,甲酰基、乙酰基和丙酰基是有效的功能团。本文介绍将甲酰基引进偶氮氯膦类试剂以后所得到的间(对)甲酰基偶氮氯膦Ⅰ对甲酰基偶氮氯膦 2-(4-氯-2-膦酸基苯偶氮)-7-(4-甲酰基苯偶氮)-1,8-二羟基萘-3,6-二磺酸Ⅱ间甲酰基偶氮氯膦 2-(4-氯-2-膦酸基苯偶氮)-7-(3-甲酰基苯偶氮)-1,8-二羟基-3,6-二磺酸

关键词：显色反应点滴试验络合物配位化合物稀土元素 ⅢB族元素轻稀土稀土族显色剂染色助剂偶氮最大吸收波长 HCI 双偶氮衍生物络合反应吸收光谱

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对(间)氨磺酰基偶氮氯膦的合成及其应用

化学试剂 1985年第1期 6-8页

作者：陈震华芦彩霞张华山汪双清武汉大学化学系武汉大学化学系

氨磺酰基—SO2NH2属于吸电子功能基,具有很好的亲水性能,因此我们将其引入偶氮膦类变色酸双偶氮衍生物,获得对氨磺酰基偶氮氯膦（Ⅰ）和间氨磺酰基偶氮氯膦（Ⅱ）两种新显色剂: （Ⅰ）4-SO1NH2对氮磺酰基偶氮氯膦（Ⅱ）3-SO2NH2间氨... 详细信息

氨磺酰基—SO2NH2属于吸电子功能基,具有很好的亲水性能,因此我们将其引入偶氮膦类变色酸双偶氮衍生物,获得对氨磺酰基偶氮氯膦（Ⅰ）和间氨磺酰基偶氮氯膦（Ⅱ）两种新显色剂: （Ⅰ）4-SO1NH2对氮磺酰基偶氮氯膦（Ⅱ）3-SO2NH2间氨磺酰基偶氮氯膦本文用试剂磺胺经重氮化与偶合反应（与偶氮氯膦Ⅰ偶合）得到化合物（Ⅰ）。合成化合物（Ⅱ）需先制得间氨基苯磺酰胺,我们参照文献[1]经以下步骤合成了该化合物:

关键词：磺酰基新显色剂偶合反应变色酸亲水性能磺酸基磺酰胺氨基苯磺酸质子化常数吸电子

Sm and Mn co-doped PMN-PT piezoelectric ceramics:Defect engineering strategy to achieve large d_(33)and high Q_(m)

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Journal of Materials Science & Technology 2023年第6期137卷 143-151页

作者： Yixiao Yang Enwei Sun Zhimin Xu huashan Zheng Bin Yang Rui zhang Wenwu Cao Condensed Matter Science and Technology Institute School of Instrumentation Science and EngineeringHarbin Institute of TechnologyHarbin 150080China Department of Mathematics and Materials Research Institute The Pennsylvania State UniversityUniversity ParkPA 16802USA

PbTiO_(3)-based piezoelectric ceramics are key materials for developing various electromechanical *** high-power ultrasonic transducers,piezoelectric ceramics are required to possess large piezo-electric coefficient(d_(33))and high mechanical quality factor(Q_(m)).Although acceptor dopants can im-prove Q_(m),they also deteriorate d_(33).If suitable piezoelectricity-beneficial donor dopants can be intro-duced into acceptor-doped ceramics,it is very possible to obtain large d_(33)and high Q_(m)simultaneously in donor and acceptor co-doped *** this work,a series of x mol%Sm and y mol%Mn co-doped Pb(Mg_(1/3)Nb_(2/3))O_(3)-30PbTiO_(3)(PMN-30PT:x Sm,y Mn)ceramics were prepared by the solid-phase sintered *** crystal structure,local domain structure and electromechanical properties were sys-tematically *** performances were obtained in PMN-30PT:2.5Sm,1-2Mn ceramics with d_(33)=860-543 pC/N,Q_(m)=495-754,and dielectric loss tanδ=*** high performance origi-nates from the combined effects of(Mn″Ti−V_(o)^(••))^(×)defect dipoles and the local structural heterogeneity.

关键词： PMN-PT ceramics Sm and Mn co-doped Electromechanical properties Defect dipoles Local structural heterogeneity

侧流烟气不同尺度颗粒物对CHO细胞微核率和细胞周期的影响

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解放军预防医学杂志 2017年第2期35卷 110-113页

作者：李秋月张华山田蕾刘焕亮林本成袭革广西医科大学公共卫生学院南宁530021 军事医学科学院卫生学环境医学研究所

目的研究侧流烟气不同尺度颗粒物对中国仓鼠卵巢细胞(CHO)微核率和细胞周期的影响,为评估侧流烟气的危害提供科学依据。方法利用侧流烟气颗粒物样品采用体外微核试验的方法,对侧流烟气中不同尺度颗粒物提取液的遗传毒性进行测试;然后采... 详细信息

目的研究侧流烟气不同尺度颗粒物对中国仓鼠卵巢细胞(CHO)微核率和细胞周期的影响,为评估侧流烟气的危害提供科学依据。方法利用侧流烟气颗粒物样品采用体外微核试验的方法,对侧流烟气中不同尺度颗粒物提取液的遗传毒性进行测试;然后采用流式细胞技术分析不同尺度颗粒物对CHO细胞周期和细胞凋亡的影响。结果侧流烟气不同粒径颗粒物对CHO均具有遗传毒性。侧流烟气不同粒径颗粒物对CHO均会造成细胞周期阻滞和引起细胞凋亡,且与对照组相比,随颗粒粒径减小呈增加趋势。结论侧流烟气中不同粒径颗粒物均对CHO具有遗传毒性,并影响细胞周期引发细胞凋亡,其毒性作用随颗粒粒径减小呈增大趋势。

关键词：侧流烟气粒径尺寸遗传毒性细胞周期细胞凋亡

The role of cholesterol metabolism in lung cancer

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Oncology Research 2024年第10期32卷 1613-1621页

作者： WEIGANG XIU XINGYU LIU KAIXIN HU QIN zhang huashan SHI Department of Thoracic Oncology and State Key Laboratory of Biotherapy Cancer CenterWest China HospitalSichuan UniversityChengdu610041China West China School of Medicine Sichuan UniversityChengdu610041China Department of Postgraduate Students West China School of MedicineChengdu610041China Department of Biotherapy Cancer CenterWest China HospitalSichuan UniversityChengdu610041China

Elevated serum cholesterol metabolism is associated with a reduced risk of lung *** cholesterol metabolism is evident in both lung cancer patients and tumor *** tumor cell cholesterol uptake or biosynthesis pathways,through the modulation of receptors and enzymes such as liver X receptor and sterolregulatory element binding protein 2,effectively restrains lung tumor ***,promoting cholesterol excretion yields comparable *** metabolites,including oxysterols and isoprenoids,play a crucial role in regulating cholesterol metabolism within tumor cells,consequently impacting cancer *** lung cancer patients,both the cholesterol levels in the tumor microenvironment and within tumor cells significantly influence cell growth,proliferation,and *** effects of cholesterol metabolism are further mediated by the reprogramming of immune cells such as T cells,B cells,macrophages,myeloid-derived suppressor cells,among *** research is investigating drugs targeting cholesterol metabolism for clinical ***,targeting the cholesterol biosynthesis pathway,are widely employed in lung cancer treatment,either as standalone agents or in combination with other ***,drugs focusing on cholesterol transportation have shown promise as effective therapies for lung *** this review,we summarized current research regarding the rule of cholesterol metabolism and therapeutic advances in lung cancer.

关键词： Cholesterol metabolism Lung cancer Immune cells Targeted strategies

Responses of nitrogen cycling and related microorganisms to brackish wetlands formed by evapotranspiration

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Pedosphere 2024年第1期34卷 252-266页

作者： Jiaohui FANG Tianshu LU Jian LIU Shangbin HE Xiufeng YANG huashan DOU Honghai zhang School of Life Sciences Qufu Normal UniversityQufu 273100China Environment Research Institute Shandong UniversityQingdao 266237China Hulunbuir Academy of Inland Lakes in Northern Cold&Arid Areas Hulunbuir 021000China

Elevated evapotranspiration due to warmer air temperature could raise salinity and nutrient levels of some inland wetlands, potentially impacting nitrogen cycling. To characterize the impact of high evapotranspiration on soil microbial nitrogen cycling in inland wetlands, we compared freshwater and brackish marsh(or non-marsh) wetlands in terms of sediment ammonia-oxidizing rate(AOR), denitrifying rate(DR), and related microbial communities in a typical inland basin, the Hulun Lake basin, in China. Results showed that marsh ecosystems(ME) exhibited 31% higher AOR and 65% higher DR than non-marsh ecosystems(NE). For NE, freshwater non-marsh wetland exhibited 12% higher AOR than brackish non-marsh wetland. This was probably due to the inhibitory effects of high NH_4~+ and salinity levels on ammonia-oxidizing archaea in brackish non-marsh wetland. Conversely, DR in brackish non-marsh wetland was 23% higher than that in freshwater non-marsh wetland, with total organic carbon(TOC) significantly influencing this difference,suggesting that the higher DR in brackish non-marsh wetland was mainly due to its higher TOC level. For ME, due to the direct and indirect interference of salinity, brackish marsh wetland displayed 26% lower AOR and 19% lower DR than freshwater marsh wetland. Besides, brackish wetlands harbored distinct ammonia-oxidizing and denitrifying microbial communities compared to freshwater wetlands. The assembly of these communities was dominated by stochastic processes, while brackish wetlands exhibited more prominent deterministic processes than freshwater wetlands. Overall, high evapotranspiration altered activities and community characteristics of ammonia oxidizers and denitrifiers in inland brackish wetlands by enhancing salinity and nutrient levels,while emergent plants occurring in ME could mitigate the adverse effects of salt stress of inland brackish wetlands on nitrogen cycling.

关键词： ammonia-oxidizing archaea ammonia-oxidizing bacteria aquatic plants denitrifying bacteria nitrogen transformation inland wetlands

Experimental Investigation of Crystal Structure of Zr 0.98 NiGe 2.94 and Phase Equilibria in Zr-Ni-Ge System

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Journal of Harbin Institute of Technology(New Series) 2023年第4期30卷 1-14页

作者： Zhengyang Wang Weijing Zeng Hong zhang huashan Liu School of Materials Science and Engineering Central South UniversityChangsha 410083China Key Lab of Non-Ferrous Metal Materials Science and Engineering Ministry of EducationCentral South UniversityChangsha 410083China

Based on the results of electron probe microanalysis(EPMA)and X-ray diffraction(XRD),the isothermal sections of Zr-Ni-Ge ternary system at 973 K and 1173 K were constructed through alloy sampling *** is worth noting that the crystallographic information of the formerly reportedτ2(Zr_(0.98)NiGe_(2.94))was determined,which belongs to the space group Pbcm(No.57).Besides the formerly reported ternary compounds,τ1(Zr_(6)Ni_(16)Ge_(7)),τ_(2)(Zr_(0.98)NiGe_(2.94)),τ_(3)(Zr_(3)Ni_(4)Ge_(4)),τ_(4)(ZrNiGe)andτ_(5)(Zr_(2)Ni_(0.54)Ge_(0.46)),a new ternary phase namedτ_(6)with the composition of Zr_(39)Ni_(18)Ge_(43)was primarily detected in this *** addition,an invariant reaction Ni_(5)Ge_(3)+τ_(4)τ_(1)+τ_(3)between 973 K and 1173 K was deduced.

关键词： Zr-Ni-Ge system phase diagram isothermal section crystal structure Zr_(0.98)NiGe_(2.94)