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Chemical composition analysis on industrial scale ingots and castings of TiAl alloys

China Foundry 2020年第6期17卷 441-446页

作者： xian-fei Ding Yi-qun Zhao Jia-bin zuo Xin Feng Hai Nan Yong-feng Liang Yan-qing Su Cast Titanium Alloy R&D Center Beijing Institute of Aeronautical MaterialsBeijing 100095China Beijing Engineering Research Center of Advanced Titanium Alloy Precision Forming Technology Beijing 100095China BAIMTEC Material Co. Ltd.Beijing 100094China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology HarbinHarbin150001China

The chemical composition variation of the TiAl-4722 alloys was examined in a batch of the industrial scale master ingots,and in the corresponding castings prepared by conventional vacuum arc remelting(VAR)combined with induction skull melting(ISM)and investment casting *** content changes of major elements and interstitial elements were evaluated based on the chemical analysis at the top and bottom of the ingots and *** show that the contents of C,N,H,Fe and Si have almost no change in the ingots and castings,suggesting that the chemical analysis on these elements can be based on the batch *** O content keeps almost the same in different ingots,but exhibits relatively large differences in castings,which was probably influenced by the reaction between the shell mold and the molten alloy,and the spalling of face coat of the shell mold during *** the major elements of Al,Nb and Cr,the composition difference between the top and the bottom of the ingots is less than that of the *** for the O element,the trend is different,especially for the castings,suggesting that the investment casting is a homogenization process for Cr and Nb,but a differentiation process for *** contents of major elements in castings fluctuate mainly in the same range as that in the ingots,indicating that the contents of the major elements are controllable during investment casting.

关键词： TiAl alloys melting casting chemical composition casting ingot

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猫儿山自然保护区不同林分类型土壤有机碳储量及其剖面分配特征

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土壤通报 2024年第4期55卷 968-973页

作者：朱柳霏戴艳花黎立港吴滢宋贤冲王会利覃祚玉谭一波邓小军广西壮族自治区林业科学研究院国家林业局中南速生材繁育实验室广西优良用材林资源培育重点实验室广西南宁530002 广西漓江源森林生态系统国家定位观测研究站桂林兴安漓江源森林生态系统广西野外科学观测研究站广西桂林541316 广西国有博白林场广西玉林537600 广西林用新型肥料研发中心广西南宁530002

【目的】揭示猫儿山自然保护区3种不同林分类型土壤有机碳储量差异及其剖面垂直分布特征,为该区域林业碳汇发展提供科学理论依据。【方法】以猫儿山水青冈天然次生林、毛竹人工林、杉木人工林3种典型林分作为研究对象,采用野外调查结合... 详细信息

【目的】揭示猫儿山自然保护区3种不同林分类型土壤有机碳储量差异及其剖面垂直分布特征,为该区域林业碳汇发展提供科学理论依据。【方法】以猫儿山水青冈天然次生林、毛竹人工林、杉木人工林3种典型林分作为研究对象,采用野外调查结合室内分析的方法,测定并计算各林分土壤容重、有机碳含量、有机碳密度和有机碳储量,并根据各林分结果数据来分析不同林分土壤有机碳储量差异及其剖面垂直分布特征和占比规律。【结果】不同林分类型土壤有机碳含量、有机碳密度及有机碳储量均表现为:水青冈天然次生林>毛竹人工林>杉木人工林。不同土层土壤有机碳含量、有机碳密度及有机碳储量存在显著差异,且均随土层加深有机碳含量等指标降低。水青冈林分土壤总有机碳储量最高,为332.99 t hm^(-2);杉木林分土壤总有机碳储量最低,为225.27 t hm^(-2)。有机碳储量占比也是随土层加深而逐渐变小,土层越深,占比越小。【结论】水青冈天然次生林土壤有机碳储量高于毛竹人工林、杉木人工林,有较好的碳储量积累与固定效应。

关键词：猫儿山林分类型土壤有机碳有机碳储量分配特征

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Linear and Interactive Effects of Air Pollution and Diurnal Temperature Range on COPD Mortality in Weifang,China:A Time Series Analysis

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Biomedical and Environmental Sciences 2021年第8期34卷 662-666页

作者： DIAO Li Jie GAO Zhi Hao JIANG Yi Chen CHEN zuo Sen LI Ning MENG xian Feng XU Xin LI Jing School of Public Health Weifang Medical UniversityWeifang 261053ShandongChina Weifang Center for Disease Control and Prevention Weifang 261061ShandongChina Affiliated Hospital of Weifang Medical University Weifang 261031ShandongChina "Health Shandong"Major Social Risk Prediction and Governance Collaborative Innovation Center Weifang 261053ShandongChina

Chronic obstructive pulmonary disease(COPD),which is characterized by a long-term,irreversible airway limitation and persistent respiratory symptoms,is common and *** studies have suggested that particulate matter is associated with the prevalence of COPD and the risk of *** the same time,the diurnal temperature range(DTR)has been suggested to be an adverse health factor that is especially associated with an increased risk of hospitalization in patients with COPD[1].DTR represents temperature variability within 1 day and is considered an important indicator of climate change.A few studies have shown that ambient air pollutants[particulate matter(PM)],such as PM2.5 and PM10,and high or low temperature have a synergistic effect on COPD[1].Thus,the current study determined the interaction between particulate matter(PM)and the DTR on COPD mortality and identified the vulnerable population in Weifang.

关键词： mortality respiratory irreversible

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超低渗致密砂岩和页岩储层渗流能力瞬态法评价进展

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石油科学通报 2024年第4期9卷 659-678页

作者：贾趵赵宇鲜成钢余凯曹炜贾文峰左玄中国石油大学(北京)油气资源与工程全国重点实验室北京102249 中国石油大学(北京)非常规油气科学技术研究院北京102249 大庆油田有限责任公司勘探开发研究院大庆163712 黑龙江省油层物理与渗流力学重点实验室大庆163712 中国石油西南油气田公司勘探开发研究院成都610041 中国石油长庆油田公司油气工艺研究院西安710018

致密砂岩和页岩储层已逐渐成为全球油气产量增长的主要来源。准确的储层评价是实现油气田高效开发的关键,其中实验测量油气储层渗流能力是评价工作的重要内容之一。传统的渗透率测量方法基于稳态方法,即在岩心进出口压降达到平衡时,根... 详细信息

致密砂岩和页岩储层已逐渐成为全球油气产量增长的主要来源。准确的储层评价是实现油气田高效开发的关键,其中实验测量油气储层渗流能力是评价工作的重要内容之一。传统的渗透率测量方法基于稳态方法,即在岩心进出口压降达到平衡时,根据达西定律计算渗透率。然而,对于超低渗和页岩储层,稳态方法难以应用。因此,采用瞬态法替代稳态法,压力脉冲衰减实验成为研究超低渗透率的常用手段。本文全面分析了近50年来压力脉冲衰减实验的发展历程,重点评述了具有代表性的论文成果,针对现有技术手段的不足,提出了需要加强的超低渗透多孔介质渗流基础研究方向。目前,一维近似解析解和数值模型已能进行高精度超低渗透率计算,二维和三维模型也在快速发展中。然而,将复杂形态裂缝及多尺度裂缝高效地嵌入压力脉冲衰减模型仍是亟待解决的关键问题。对于页岩气等吸附性气体,明确静态吸附与动态吸附的区别以及将吸附曲线有效地纳入流动模型是需要深入探讨的基础科学问题。基于此,可通过压力脉冲衰减实验评估多物理作用下的岩石物理特性。此外,系统研究相对低压状态下的非达西渗流行为也是促进压力脉冲衰减实验科学计算的重要途径。总的来说,几十年来,超低渗岩心储渗能力评价的实验和模拟取得了显著进展,进一步深入理论研究和先进实验装置研发具有重要应用需求,相关研究进展对我国致密和页岩油气藏的高效勘探开发以及保障国家能源安全具有重要战略意义。

关键词：致密储层页岩储层瞬时方法压力脉冲衰减裂缝解析解模型数值模拟非达西

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Tradeoffanalysis of the pork supply and food security under the influence of African swine fever and the COVID-19 outbreak in China

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Geography and Sustainability 2022年第1期3卷 32-43页

作者： Huizong Yao Chuanfu Zang Xiaoxing zuo Yuyang xian Yongquan Lu Yutong Huang xianbing Li Chinese Research Academy of Environmental Sciences Beijing 100012China School of Geography South China Normal UniversityGuangzhou 510631China South University of Science and Technology of China Shenzhen 518055China

China is the world’s largest consumer of pork and ***,African swine fever(ASF)and the COVID-19 outbreak have greatly impacted the pork supply and food security in *** can food security and the pork supply be ensured under the dual impacts of COVID-19 and ASF?This is a major problem to be urgently solved by the Chinese *** study indicated that the main pork production and sales areas in China were separated,which reflected the spatial imbalance between the supply and *** total area of suitable selected sites for pig farms in China is 21.5 million *** only the areas with levels of high and moderate suitability are considered as potential sites for pig farms,the potential pork production can reach 56.1 million tons in China,which is slightly lower than *** to the impact of the ASF epidemic,the food consumed by pigs has been reduced by 34.7 million ***,with increasing pork productivity in the future,the self-sufficiency rate of grains may further *** the premise that the quality of people’s life is not affected,the diversification of meat supply channels should be realized in an orderly and sustainable way,which might alleviate the pressure on food *** study provides a theoretical reference for the spatiotemporal layout of the swine industry and addresses the issue of food security in China under the influence of ASF and the COVID-19 outbreak.

关键词： African swine fever COVID-19 outbreak Suitability analysis Food security Pork production potential

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Observation of Low-Lying and Linking Transitions in ^(124)Cs

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Chinese Physics Letters 2001年第1期18卷 21-23页

作者： LU Jing-Bin LIU Yun-zuo YIN Li-Chang ZHANG Fan WU Xiao-Guang WEN Shu-xian LI Guang-Sheng yang Chun-xiang Department of Physics Jilin UniversityChangchun 130023 China Institute of Atomic Energy Beijing 102413

The level states of the nucleus ^(124)Cs have been populated through the ^(116)Sn(^(11) B,3n)reaction at a beam energy of 45MeV,provided by the HI-13 tandem accelerator of the China Institute of Atomic Energy.A number of low-lying states are *** level states in theπh_(11/2)νg_(7/2) side band are extended down to lower spin by one *** level energies and spins in the rotational bands are determined through the establishment of various connections,which confirm the spin assignment of the yrast band in ^(124)Cs based on excitation energy *** is revealed that with the present spin assignment,theπh_(11/2)νg_(7/2) side band shows signature inversion at low-spin region and the inversion occurs at a spin of about 16h.

关键词： assignment Transition

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Salvia miltiorrhiza extract may exert an anti-obesity effect in rats with high-fat diet-induced obesity by modulating gut microbiome and lipid metabolism

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World Journal of Gastroenterology 2022年第43期28卷 6131-6156页

作者： Zi-Li Ai xian Zhang Wei Ge You-Bao Zhong Hai-Yan Wang Zheng-Yun zuo Duan-Yong Liu Department of Postgraduate Jiangxi University of Chinese MedicineNanchang 330004Jiangxi ProvinceChina Department of Proctology Affiliated Hospital of Jiangxi University of Chinese MedicineNanchang 330006Jiangxi ProvinceChina Laboratory Animal Research Center for Science and Technology Jiangxi University of Chinese MedicineNanchang 330004Jiangxi ProvinceChina Formula-Pattern Research Center Jiangxi University of Chinese MedicineNanchang 330004Jiangxi ProvinceChina

BACKGROUND Studies have shown that a high-fat diet(HFD) can alter gut microbiota(GM)homeostasis and participate in lipid metabolism disorders associated with ***, regulating the construction of GM with the balance of lipid metabolism has become essential for treating obesity. Salvia miltiorrhiza extract(Sal), a common traditional Chinese medicine, has been proven effective against atherosclerosis, hyperlipidemia, obesity, and other dyslipidemia-related *** To investigate the anti-obesity effects of Sal in rats with HFD-induced obesity, and explore the underlying mechanism by focusing on GM and lipid *** Obesity was induced in rats with an HFD for 7 wk, and Sal(0.675 g/1.35 g/2.70g/kg/d) was administered to treat obese rats for 8 wk. The therapeutic effect was evaluated by body weight, body fat index, waistline, and serum lipid level. Lipid factors(cAMP, PKA, and HSL) in liver and fat homogenates were analyzed by ELISA. The effect of Sal on GM and lipid metabolism was assessed by 16S rRNAbased microbiota analysis and untargeted lipidomic analysis(LC-MS/MS),*** Sal treatment markedly reduced weight, body fat index, serum triglycerides(TG), total cholesterol(TC), low-density lipoprotein, glucose, free fatty acid, hepatic lipid accumulation, and adipocyte vacuolation, and increased serum high-density lipoprotein(HDL-C) in rats with HFD-induced obesity. These effects were associated with increased concentrations of lipid factors such as c AMP, PKA, and HSL in the liver and adipose tissues, enhanced gut integrity, and improved lipid metabolism. GM analysis revealed that Sal could reverse HFD-induced dysbacteriosis by promoting the abundance of Actinobacteriota and Proteobacteria, and decreasing the growth of Firmicutes and Desulfobacterita. Furthermore, LC-MS/MS analysis indicated that Sal decreased TGs(TG18:2/18:2/20:4, TG16:0/18:2/22:6), DGs(DG14:0/22:6, DG22:6/22:6), CL(18:2/18:1/18:1/20:0), and increased ceramides

关键词： Salvia miltiorrhiza extract Obesity Gut microbiota Lipid metabolism High fat diet

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The Role of Calcium in Mediating SlIAAs Expression in Tomato Pedicel Explants

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Agricultural Sciences in China 2010年第7期9卷 980-984页

作者： zuo xian-hong XU Tao QI Ming-fang LU Shuang-shuang LI Jin-hong LI Hong GAO Song LI Tian-lai Key Laboratory of Protected Horticulture of Liaoning Province/College of Horticulture Shenyang Agricultural University Shenyang 110161 P.R. China

In order to illuminate the effect of calcium on the IAA signal transduction,we studied the expression of eight SlIAA genes which were up-regulated by calcium during the abscission after short-term（1 h） and long-term（16 h） treatments with calcium,IAA and calcium *** results indicated that calcium induced SlIAAs expression in 1 h at low concentration,EGTA affected little SlIAAs expression;it also increased IAA-induced transcript level of SlIAAs,TFP（named trifluoperazine） decreased most SlIAAs expression below the level of calcium combined with IAA-induced expression,except for ***-term treatment of calcium or calcium inhibitors suppressed some SlIAAs expression,whereas TFP enhanced all SlIAAs ***,SlIAA29 was induced by most treatments excluding 16 h EGTA.

关键词： tomato calcium IAA calcium inhibitors SIlAA gene

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3907例儿童近视早期眼底改变在不同眼轴的分布及其人工智能量化监控指标

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临床眼科杂志 2024年第2期32卷 97-101页

作者：石一宁方严陈卓王妮左浩陕西省人民医院 710000 安徽理工大学第一附属医院淮南232007 西安医学院药学院陕西西安新城石一宁眼科诊所

目的采用人工智能技术对儿童近视早期眼底的微量变化进行定性、定量分析,结合相关眼生物参数,探索近视发展的内在规律,为儿童近视防控工作中的早期发现、及时监测、适时调整提供敏感指标。方法横断面研究。对3907例18岁以下门诊顺序就... 详细信息

目的采用人工智能技术对儿童近视早期眼底的微量变化进行定性、定量分析,结合相关眼生物参数,探索近视发展的内在规律,为儿童近视防控工作中的早期发现、及时监测、适时调整提供敏感指标。方法横断面研究。对3907例18岁以下门诊顺序就诊儿童的眼底及相关生物参数进行采集,并按年龄分为6组,眼轴分为8组。分别采用SW‐9000眼科光学生物测量仪、SW‐8800眼底照相机,OSE‐2800眼科光学相干断层扫描仪和EVisionAI依未眼底智能分析云平台。依据SHI’标准中国眼健康档案及诊断体系,每一位患者每次就诊均按设计流程进行11项+眼生物参数进行完整的数据采集。近视早期眼底指标依次有垂直杯/盘(C/D)比、豹纹状改变和弧形斑。采用SPSS 19.0(SPSS Inc,Chicago,IL,USA)进行统计,包括χ2分析、ANOVA方差分析和多元逐步线性回归分析。结果3907例18岁以下儿童中,男生55.8%,女生44.2%;右眼和左眼分别50%。就诊高峰为6~11岁(64%)。眼轴23.5~25.5 mm占总人数的53.5%。眼轴25.5 mm以上各组占16.9%。垂直C/D比0.4~0.5占77%(χ2检验,P=0.000);眼轴24.5 mm以下各组呈现1级或无豹纹状改变,弧形斑多为生理改变;眼轴24.5~25.5 mm组呈现4级豹纹状改变;眼轴24.5 mm以上各组主要表现为3级弧形斑,26.5 mm以上眼轴为4级弧形斑(P组间=0.000,P总=0.000,P相关性<0.002)。结论24.5 mm眼轴可作为学龄儿童近视防控的监测关键拐点,豹纹状改变0.1、弧形斑1 PD视为诊断指标,豹纹状改变0.04~0.09、弧形斑2/3 PD视为病理性改变前期或高危期诊断指标。

关键词：儿童近视初发近视眼轴眼生物参数人工智能

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热环境下功能梯度圆柱壳振动特性分析

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振动工程学报 2023年第2期36卷 526-533页

作者：石先杰左朋中国工程物理研究院总体工程研究所四川绵阳621999 中国科学技术大学工程科学学院近代力学系安徽合肥230026

应用谱几何法研究了热环境下功能梯度圆柱壳自由振动和瞬态振动特性。采用边界弹簧技术模拟圆柱壳结构的任意经典或者弹性边界约束条件,并结合一阶剪切变形理论建立了考虑温度场作用的功能梯度圆柱壳结构能量泛函。采用谱几何法与周向... 详细信息

应用谱几何法研究了热环境下功能梯度圆柱壳自由振动和瞬态振动特性。采用边界弹簧技术模拟圆柱壳结构的任意经典或者弹性边界约束条件,并结合一阶剪切变形理论建立了考虑温度场作用的功能梯度圆柱壳结构能量泛函。采用谱几何法与周向傅里叶谐波函数乘积和的形式描述圆柱壳的位移容许函数,以克服不同边界条件下壳体位移函数微分在边界上存在的不连续问题。在此基础上,将位移容许函数代入至结构能量泛函,并采用Ritz法获得结构振动分析模型。数值分析结果表明,所构建分析模型能够快速准确预测功能梯度圆柱壳结构的振动特性。研究了幂律指数、温度、载荷等参数对功能梯度圆柱壳振动特性的影响规律,为其他数值分析方法研究提供参考。

关键词：自由振动功能梯度圆柱壳热环境谱几何法瞬态响应

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