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Thermodynamics of Solvent Extraction of Rare and Scattered Metal-Indium with Diethylhexylmonothiophosphoric Acid

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Chemical Research in Chinese Universities 2006年第1期22卷 111-113页

作者： LIU Xing-zhi ZANG shu-liang FANG Da-wei LI Jun WANG Lu-ning Institute of Chemical Science and Engineering Liaoning University Shenyang 110036 P. R. China

The thermodynamics of extracting In（ Ⅲ） with diethylhexylmonothiophosphoric acid as an extractant in a H2SO4 system is reported. The equilibrium molalities of In^3＋ ions were measured at a high acidity and ionic strengths varying from 0. 1 to 2.0 mol/kg in an aqueous phase containing Na2SO4 as the supporting electrolyte. The values of the standard extraction constant K^0 at various temperatures were obtained by the methods of extrapolation and polynomial approximation. The equation lgK^0 = - 51.95 - 5.93 × 10^3/T ＋ 6. 15 × 10^-2 T was also obtained and the thermodynamic quantities for the extraction process were calculated.

关键词： Extraction Indium Diethylhexylmonothiophosphoric acid Thermodynamics

雷公藤甲素通过抑制细胞铁死亡减轻博来霉素诱发的小鼠肺纤维化

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中国病理生理杂志 2024年第4期40卷 662-669页

作者：张致琴吴洁秦艺璐梁舒左淑飞张超高晓范文强张志强新乡医学院第一附属医院河南新乡453100 新乡市中心医院河南新乡453000

目的:探讨雷公藤甲素(TPL)对博来霉素(BLM)诱导肺纤维化小鼠的改善效果,揭示铁死亡参与TPL改善肺纤维化的潜在机制。方法:选择SPF级小鼠,随机分为3组:对照组、模型组(BLM处理组)和实验组(BLM+TPL处理组),每组10只。Day 0,模型组和实验... 详细信息

目的:探讨雷公藤甲素(TPL)对博来霉素(BLM)诱导肺纤维化小鼠的改善效果,揭示铁死亡参与TPL改善肺纤维化的潜在机制。方法:选择SPF级小鼠,随机分为3组:对照组、模型组(BLM处理组)和实验组(BLM+TPL处理组),每组10只。Day 0,模型组和实验组小鼠气管灌注BLM水溶液(50μL,5 mg/kg),对照组小鼠接受等体积的生理盐水。Day 1起,实验组小鼠开始灌胃TPL悬液(200μL,0.25 mg/kg),每3 d一次,共7次,对照组和模型组分别接受等体积生理盐水。Masson染色检测肺组织纤维化,TUNEL染色检测肺组织细胞凋亡;体外CCK8法检测细胞活力,流式细胞术及活死染色检测细胞凋亡,免疫荧光法检测细胞脂质过氧化,Western blot检测肺组织及细胞中目的蛋白表达。结果:TPL处理通过下调肺组织中Ⅰ型胶原(Col Ⅰ)和α-平滑肌肌动蛋白(α-SMA)的表达(P<0.05),显著降低BLM诱导小鼠肺部纤维化程度(P<0.01);同时,TPL处理可显著上调肺组织中谷胱甘肽过氧化酶4(GPX4)和铁死亡抑制蛋白1(FSP1)表达(P<0.05),下调转铁蛋白受体1(TfR1)表达(P<0.05),从而抑制BLM诱导的肺部细胞铁死亡和凋亡(P<0.01)。体外研究结果表明,TPL处理可显著抑制肺上皮细胞凋亡(P<0.01),进一步检测发现TPL处理可显著降低BLM诱导的肺泡上皮细胞内脂质过氧化(P<0.01),显著上调细胞内GPX4和FSP1蛋白表达(P<0.01),下调TfR1蛋白表达(P<0.05),通过抑制细胞铁死亡来显著降低BLM诱导的肺上皮细胞凋亡率。结论:TPL可在体内外通过抑制BLM诱导的细胞铁死亡,改善肺部细胞活力,降低细胞凋亡率,从而减轻肺小鼠纤维化程度。本研究为临床使用TPL治疗肺间质病变提供理论依据。

关键词：雷公藤甲素肺纤维化肺间质病变铁死亡博来霉素

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中国老年人群艾滋病知识知晓率的Meta分析

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中国艾滋病性病 2024年第4期30卷 441-446,F0003页

作者：叶志华袁将何佳彭瑾张瑞曦王俊舟李双如梁姝杨义成都中医药大学管理学院/健康四川研究院成都611137 成都中医药大学公共卫生学院成都611137 成都市武侯区红牌楼社区卫生服务中心成都610041 四川省疾病预防控制中心成都610041

目的更新中国老年人群艾滋病知识知晓率系统评价结果,分析时间、地区和人群分布特征。方法检索CNKI、SinoMed、WangFang Data、VIP、Web of Science、PubMed、Embase、Elsevier ScienceDirect和The Cochrane Library数据库中国老年人群艾滋病知识知晓率文献,时限均为2018年1月1日至2023年9月30日。由2位研究者独立筛选文献、评价质量,并提取信息,采用R 4.3.1软件进行Meta分析。结果共纳入26项研究包含中国老年人群25905人。Meta分析结果显示,中国老年人群艾滋病知识知晓率为51.95%(95%CI:43.31%~60.53%)。时间分布显示,2015-2021年中国老年人群艾滋病知识知晓率上升缓慢,2019年与2021年出现下降。亚组分析结果显示,西南地区、70岁及以上、小学及以下文化程度和农村地区老年人群知晓率更低,老年高危人群和使用非概率抽样的研究知晓率更高。结论我国老年人群艾滋病知识知晓率偏低,“十三五”以来知晓率增长缓慢,未得到有效提升。西南地区、高龄、低文化程度、农村地区和高危老年人群的艾滋病健康教育工作应持续加强。受纳入研究质量与数量限制,上述结论尚需更多高质量文献予以验证。

关键词：老年人群艾滋病知晓率 Meta分析

Spectrophotometric determination of cationic surfactants by formation of ternary complexes with Fe(Ⅲ) and chrome azurol S

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Chinese Journal of Chemistry 1996年第3期14卷 228-234页

作者： SONG, Ming liang, shu-Quan Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

An extraction-free spectrophotometric method for the determination of cationic surfactants, such as cetylpyridinium chloride, cetyltrimethylammonium bromide and zephiramine is proposed, which is based on the formation of ternary complexes with Fe(Ⅲ) and chrome azurol S. The molar ratio of the complex is 2:1:1 (Fe(Ⅲ):chrome azurol S:cationic surfactant). The method is simple, rapid and sensitive, giving an apparent molar absorptivity of 4.5×104 ***-1 and a linear range of 0.1-6.0 umol/L cationic surfactants. The total cationic surfactant content can be determined directly in aqueous solutions by measuring the absorbance at 680 nm (pH 5.8). The method has been successfully applied to water samples.

关键词： Cationic surfactant determination spectrophotometry ternary complex Fe(Ⅲ) chrome azurol S

Generation of orthogonal UWB shaping pulses based on compressed chirp signal

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The Journal of China Universities of Posts and Telecommunications 2007年第2期14卷 99-102页

作者： CHE shu-liang ZHANG Hong-xin LU Ying-hua HE Peng-fei College of Physics and Electronic Engineering the Centre University for Nationalities Beijing 100081 China School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This study investigates a novel method to numerically generate orthogonal ultrawide band （UWB） shaping pulses based on compressed chirp signal. First, a pulse template with less than 1 ns duration time, which is used to construct a Hermitian matrix, is produced with a compressed chirp pulse. Sub-nanosecond orthogonal pulses are then generated for UWB by using the Hermitian matrix eigenvectors. The simulation results show that the power spectral density distribution of the UWB shaping pulses met the constraint of Federal communications commissions （FCC） spectral mask. The shaping pulses not only have higher spectrum utilization ratio and very short time duration but also have excellent autocorrelation and cross-correlation properties, which is an advantage to reduce the interference between multiusers. Especially, a method to produce sub-nanosecond orthogonal UWB shaping pulses by using a relatively longer duration chirp signal is presented.

关键词： UWB shaping pulse spectrum utilization ratio interference between multiusers

Calculation of the ultimate depth of a scour pit after debris flow through drainage canal ribs

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Journal of Mountain Science 2016年第2期13卷 246-254页

作者： LIU shu-liang YOU Yong ZHANG Guang-ze ZHAO Hai-xin SUN Hao Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China University of Chinese Academy of Sciences Beijing 100049 China China Railway Eryuan Engineering Group co. LTD Chengdu 610031 China

Drainage canals are engineering structures widely used for debris flow *** passing through a drainage canal,debris flow usually scours the gully bed at the back of the rib sill of the drainage canal,which leads to failure of the rib ***,the scour depth at the back of the rib sill is an important design problem and it is related to the economic benefits of engineering and service *** explore the law of the depth of the scour pit after debris flow through drainage canal ribs,we first proposed a formula for the calculation of the maximum scour depth at the back of a rib sill based on energy *** then conducted a series of simulation experiments to test the proposed *** experimental results show that the scour depth,trench slope and the distance between ribs all increase with a decrease in debris flow *** then compared the results of experiments and formula *** the testing analysis,we found that the calculation results of the conductedformula correspond with the experimental results ***,taking Qipan Gully as an example,we designed the ultimate depth of a drainage canal for debris flow using the calculation formula.

关键词： Debris flow Drainage canal Scour depth Energy conservation method Flume experiment

A novel approach for radionuclide diffusion in the enclosed environment of a marine nuclear reactor during a severe accident

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Nuclear Science and Techniques 2022年第2期33卷 53-65页

作者： Fang Zhao shu-liang Zou Shou-Long Xu Xuan Wang Jun-Long Wang De-Wen Tang School of Resource Environment and Safety Engineering University of South ChinaHengyang 421001China Hunan Provincial Key Laboratory of Emergency Safety Technology and Equipment for Nuclear Facilities Hengyang 421001China Shanghai Nuclear Engineering Research and Design Institute Co.LTD Shanghai 200000China Science and Technology On Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China

A severe accident in a marine nuclear reactor leads to radionuclide leakage,which causes hidden dangers to workers and has adverse effects of environmental *** is necessary to propose a novel approach to radionuclide diffusion in a confined environment after a severe accident in a marine nuclear ***,this study proposes a new method for the severe accident analysis program MELCOR coupled with computational fluid dynamics scSTREAM to study radioactive diffusion in severe *** radionuclide release fraction and temperature calculated by MELCOR were combined with the scSTREAM calculations to study the radionuclide diffusion behavior and the phenomenon of radionuclide diffusion in different space environments of the reactor under the conditions of varying wind velocities of the ventilation system and diffusion *** results show that the wind velocity of the ventilation system is very small or zero,and the turbulent diffusion of radionuclides is not obvious and diffuses slowly in the form of condensation sedimentation and gravity *** the wind speed of the ventilation system increases,the flow of radionuclides meets the wall and forms eddy currents,affecting the time variation of radionuclides diffusing into chamber *** wind velocity of the ventilation system and the diffusion speed has opposite effects on the time variation trend of radionuclide diffusion into the four chambers.

关键词： Radionuclide diffusion MELCOR coupled with scSTREAM Severe accident Marine nuclear reactor

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骶前间隙静脉型血管瘤1例报告并文献复习

中国CT和MRI杂志 2024年第6期22卷 161-162页

作者：梁树生莫永灿朱玉莉英德市人民医院影像中心广东英德513000

目的探讨骶前间隙静脉型血管瘤的影像学表现以提高对该疾病的认识。方法分析骶前静脉型血管瘤的临床表现、MRI表现、手术纪录及病理结果。结果骶前间隙静脉型血管瘤的影像学表现主要为圆形、椭圆形实性或囊实性病灶,边界清楚,可见静... 详细信息

目的探讨骶前间隙静脉型血管瘤的影像学表现以提高对该疾病的认识。方法分析骶前静脉型血管瘤的临床表现、MRI表现、手术纪录及病理结果。结果骶前间隙静脉型血管瘤的影像学表现主要为圆形、椭圆形实性或囊实性病灶,边界清楚,可见静脉石,增强扫描渐进性延迟强化。结论影像学检查对骶前间隙静脉型血管瘤有一定的诊断价值,根据其影像学特点,可作出准确诊断。

关键词：骶前间隙血管瘤影像学诊断

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Effects of temperature and solar radiation on yield of good eating-quality rice in the lower reaches of the Huai River Basin,China

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Journal of Integrative Agriculture 2021年第7期20卷 1762-1774页

作者： ZHOU Nian-bing ZHANG jun FANG shu-liang WEI Hai-yan ZHANG Hong-cheng Jiangsu Key Laboratory of Crop Genetics and Physiology/Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops Yangzhou UniversityYangzhou 225009P.R.China Huai’an Agricultural Technology Promotion Center Huai’an 223001P.R.China

We studied the effects of temperature and solar radiation on rice yield with the aim of understanding the temperature and solar radiation requirements for high yield rice production in the lower reaches of the Huai River,*** experiments were conducted with two medium-maturing japonica rice(MMJR)varieties and four late-maturing japonica rice(LMJR)varieties in 2017 and *** were sown on May 10(T1),May 17(T2),May 24(T3),May 31(T4),June 7(T5),June 14(T6),and June 21(T7).The whole growth duration(WGD)of rice was shortened when sowing date was delayed,especially for the duration from sowing to heading(S–H).The effective accumulated temperature(EAT),mean daily temperature(Tmean),cumulative solar radiation(CSR),and mean daily solar radiation(Rmean)over the WGD decreased when sowing date was *** with T1,yields in T2,T3,T4,T5,T6,and T7 decreased by 0.12–0.35,0.45–0.89,0.74–1.56,1.41–2.24,2.16–2.90,and 2.69–3.64 t ha^(-1),*** was a significant positive correlation between rice yield and EAT in different growth *** was the main factor that affected the yield of good eating-quality rice in the lower reaches of the Huai *** found that a relatively high yield can be obtained when the optimal Tmean for medium-maturing japonica rice(MMJR)and late-maturing japonica rice(LMJR)was 25.8–27.0℃and 26.6–27.1℃in the stages from sowing to heading(S–H),and 20.3–23.3℃and 20.3–22.1℃in the stages from heading to maturity(H–M),*** optimal sowing dates for MMJR and LMJR in the lower reaches of the Huai River were May 15–31 and May 15–18,respectively.

关键词： rice yield temperature solar radiation growth stage