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Chinese Physics Letters 2000年第3期17卷 218-220页

作者： GONG zi-Zheng XIE Hong-Sen JING Fu-qian liu Yong-Gang GUO Jie XU Jian Material Laboratory of the Earth's Interior Institute of GeochemistryChinese Academy of SciencesGuiyang 550002 Laboratory for Shock Waves and Detonation Physics Research Southwest Institute of Fluid PhysicsChengdu 610003 Institute of Geosciences Academia SinicaTaipei 11529

Using the differences of sound velocity and temperature on the Hugoniot and isoentropic state,the temperature coefficients of sound velocity of perovskite-enstatite under high pressure were *** compressional,shear and bulk wave velocities,their temperature coefficients decrease from 0.386,0.251,0.255 m/(s·K)at 40 GPa to 0.197,0.131,0.162m/(S·K)at 140GPa,*** these to zero pressure results in(■K/■T)o=-0.0279 GPa·K^(-1),which is consistent very well with the value got by hydrostatic pressure *** the basis of our data,we conclude that the compressional wave velocity anomaly of 0.1-0.2%in the deep lower mantle and 2%in the D″region would imply lateral thermal heterogeneity with amplitude of 53-106 K and 1066 K in these regions,respectively.

关键词： Lower mantle anomaly

低剂量呼气相胸部CT参数与慢性支气管炎肺功能的关系分析

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罕少疾病杂志 2024年第7期31卷 43-45页

作者：郭子祺田茜廉丽敏河南省新乡市第一人民医院CT室河南新乡453000

目的分析低剂量呼气相胸部CT参数与慢性支气管炎肺功能的关系。方法选取2022年1月~2022年12月本院诊治的112例慢性支气管炎患者作为疾病组,另选取同期在本院体检中心体检的112例健康志愿者作为对照组。两组均行低剂量呼气相胸部CT扫描... 详细信息

目的分析低剂量呼气相胸部CT参数与慢性支气管炎肺功能的关系。方法选取2022年1月~2022年12月本院诊治的112例慢性支气管炎患者作为疾病组,另选取同期在本院体检中心体检的112例健康志愿者作为对照组。两组均行低剂量呼气相胸部CT扫描和肺功能检查,记录CT参数[肺容积、肺野密度、空气潴留区域肺组织容积占全肺容积的百分比(LAA%)]和肺功能指标[第1秒用力呼气容积(FEV1)、用力肺活量(FVC)、FEV1与FVC的比值(FEV1/FVC)、FEV1占预测值百分比(FEV1%)、FVC占预测值百分比(FVC%)、血氧分压(PaO2)、二氧化碳分压(PaCO2)]。采用Pearson法分析低剂量呼气相胸部CT参数与慢性支气管炎肺功能指标的相关性。结果疾病组肺容积、肺野密度、LAA%和PaCO2均高于对照组(P<0.05),FEV1/FVC、FEV1%、FVC%、PaO2均低于对照组(P<0.05);急性发作期肺容积、肺野密度、LAA%、PaCO2均高于慢性迁延期和临床缓解期(P<0.05),慢性迁延期均高于临床缓解期(P<0.05);急性发作期FEV1/FVC、FEV1%、FVC%、PaO2均低于慢性迁延期和临床缓解期(P<0.05),慢性迁延期均低于临床缓解期(P<0.05);Pearson分析结果显示,肺容积、肺野密度、LAA%与FEV1/FVC、FEV1%、FVC%、PaO2均呈负相关(P<0.05),与PaCO2均呈正相关(P<0.05)。结论慢性支气管炎患者低剂量呼气相胸部CT参数与肺功能指标存在相关性,可为临床科学治疗慢性支气管炎提供影像学参考依据。

关键词：低剂量呼气相胸部CT参数慢性支气管炎肺功能相关性

表面次生氧化矿物对FeS_(2)降解抗生素的影响及作用机制

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中国环境科学 2024年第10期44卷 5539-5546页

作者：舒小华覃紫其聂昌达周进文张腾飞张倩桂林理工大学环境科学与工程学院广西桂林541006 桂林理工大学广西环境污染控制理论与技术重点实验室广西桂林541006 桂林理工大学广西岩溶地区水污染控制与用水安全保障协同创新中心广西桂林541006 桂林电子科技大学生命与环境科学学院广西桂林541004

以广泛应用于畜牧业的大环内酯类抗生素泰乐菌素(TYL)为研究对象,探究了不同氧化腐蚀程度的黄铁矿对TYL的光降解性能和作用机制.结果表明,氧化后的黄铁矿能够显著提高其对TYL的光降解效率.具体来说,氧化后的黄铁矿样品表面粗糙度增加,... 详细信息

以广泛应用于畜牧业的大环内酯类抗生素泰乐菌素(TYL)为研究对象,探究了不同氧化腐蚀程度的黄铁矿对TYL的光降解性能和作用机制.结果表明,氧化后的黄铁矿能够显著提高其对TYL的光降解效率.具体来说,氧化后的黄铁矿样品表面粗糙度增加,比表面积扩大,增加了表面反应活性位点,从而提高了其对TYL的吸附能力.此外,氧化增强了黄铁矿表面的电子传递过程,加快了·OH产生速率,进而提高了对TYL的光降解效率.同时,黄铁矿(FeS_(2))与表面新生成的Fe_(2)O_(3)组成了异质结,有效抑制了材料内部光生电子与空穴的复合,从而进一步提高了光降解性能.

关键词：黄铁矿(FeS2) 氧化腐蚀光降解效果泰乐菌素(TYL) 次生矿物

重组人糖蛋白激素β5/α2融合蛋白在CHO-S细胞中的表达纯化及功能活性分析

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中国药理学通报 2024年第2期40卷 390-396页

作者：千爱君萧耿苗李壮梁志成穆云萍赵子建李芳红广东工业大学生物医药学院广东广州510006 华南理工大学医学院广东广州510006

目的在悬浮中国仓鼠卵巢细胞(Chinese hamster ovary cells,CHO-S)中分泌表达、纯化重组hCGH-CTP融合蛋白,验证其对3T3-L1成熟脂肪细胞脂质积累的影响。方法构建CTP连接肽融合人糖蛋白激素β5/α2重组蛋白表达载体pcDNA3.1-rhCGH-CTP,... 详细信息

目的在悬浮中国仓鼠卵巢细胞(Chinese hamster ovary cells,CHO-S)中分泌表达、纯化重组hCGH-CTP融合蛋白,验证其对3T3-L1成熟脂肪细胞脂质积累的影响。方法构建CTP连接肽融合人糖蛋白激素β5/α2重组蛋白表达载体pcDNA3.1-rhCGH-CTP,将其瞬时转染CHO-S悬浮细胞中,大量表达纯化并验证rhCGH-CTP蛋白生物学活性;通过干预3T3-L1成熟脂肪细胞24 h,观察细胞内甘油三酯(TG)水平的变化。结果Western blot结果显示,rhCGH-CTP蛋白在CHO-S细胞中成功表达,表达量可达715.4 mg·L^(-1);用AKTA pure蛋白纯化系统纯化蛋白,SDS-PAGE方法鉴定纯化出的蛋白纯度较高可达90%。此外,在高表达TSHR基因的成熟脂肪细胞3T3-L1中,利用ELISA试剂盒测定不同浓度rhCGH-CTP蛋白干预后胞内cAMP含量明显升高,说明rhCGH-CTP蛋白具有生物活性;油红O染色结果发现,与对照组相比,不同浓度rhCGH-CTP蛋白干预组的成熟脂肪细胞中TG含量明显降低(P<0.05)。结论成功表达并纯化了rhCGH-CTP融合蛋白,其具有良好的生物学活性并能有效降低TG,该研究为后续深入揭示CGH蛋白的生理作用及在临床实践中的潜在应用提供了重要基础。

关键词：重组人糖蛋白激素β5/α2融合蛋白真核表达悬浮CHO-S细胞 cAMP活性基因工程脂代谢

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常见筋板样式对球阀活门刚度影响的仿真分析

机械工程与自动化 2024年第4期 50-52页

作者：薛子萱黄钢匡振东刘向涛赵堑天津机电职业技术学院天津300350 天津国际机械有限公司天津300300 山推工程机械股份有限公司山东济宁272000

采用整体分析和单独分析两种方法,分别建立了水电球阀的整体有限元模型和活门的单独有限元模型,对比分析这两种分析法结果的吻合度。采用单独分析方法建立十字靶环形、十字形、川字形、井字形4种筋板样式活门的有限元模型,研究4种常见... 详细信息

采用整体分析和单独分析两种方法,分别建立了水电球阀的整体有限元模型和活门的单独有限元模型,对比分析这两种分析法结果的吻合度。采用单独分析方法建立十字靶环形、十字形、川字形、井字形4种筋板样式活门的有限元模型,研究4种常见筋板样式对活门刚度的影响。研究结果表明:十字靶环形筋板增加活门刚度的效果最显著;采用单独分析方法求解高效,分析结论可靠。

关键词：球阀活门筋板仿真分析

Factors Influencing the Emergency Medical Service Response Time for Cardiovascular Disease in Guangzhou, China

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Current Medical Science 2019年第3期39卷 463-471页

作者： Xiao-qian CHEN zi-feng liu Shi-kun ZHONG Xing-tang NIU Yi-xiang HUANG Ling-ling ZHANG Department of Health Policy and Management School of Public Health Sun Yat-sen University Guangzhou 510080China Department of Medicine Guanghua School of Stomotology Hospital of Stomatology Sun Yat-sen University Guangzhou 510080 China Department of Network Management Guangzhou City Emergency Care Centre Guangzhou 510080 China Department of Plastic Surgery the First Affiliated Hospital Sun Yat-sen University Guangzhou 510080China Department of Nursing College of Nursing and Health Sciences University of Massachusetts Boston Boston 02125-3393 USA

While emergency medical service (EMS) response time (ERT) is a major factor associated with the survival of patients with cardiovascular disease (CVD), relatively few studies have explored the factors associated with ERT. This study aimed to assess the current status of ERT and to identify the factors affecting ERT in patients with CVD in China. Between January 1, 2011 and December 31, 2015, EMS responses to CVD incidents in Guangzhou, China, were examined. The primary outcome was ERT, defined as the time from receipt of an emergency call to the arrival of paramedics on the scene. Factors associated with ERT were evaluated by multivariable logistic regression. A total of 44 383 CVD incidents were analysed. The median ERT was 12.58 min (interquartile range=9.98-15.67). Among the risk factors, distance (OR=13.73, 95% CI=11.76- 16.04), level of hospital (OR=1.57, 95% CI=1.40-1.75), and site of the incident (OR=1.53, 95% CI=1.38-1.69) were the top three significant factors affecting the ERT. Our results suggest that greater attention should be given to factors affecting the ERT. It is essential to make continuous efforts to promote the development of effective interventions to reduce the response time.

关键词： emergency medical service cardiovascular disease response time factors China

Supervised Vessels Classification Based on Feature Selection

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Journal of Computer Science & Technology 2017年第6期32卷 1222-1230页

作者： Bei-Ji Zou Yao Chen Cheng-Zhang Zhu Zai-Liang Chen zi-qian Zhang School of Information Science and Engineering Central South University Changsha 410083 China ‘Mobile Health' Ministry of Education-China Mobile Joint Laboratory Central South University Changsha 410083 China College of Literature and Journalism Central South University Changsha 410083 China

Arterial-venous classification of retinal blood vessels is important for the automatic detection of cardiovascular diseases such as hypertensive retinopathy and stroke. In this paper, we propose an arterial-venous classification （AVC） method, which focuses on feature extraction and selection from vessel centerline pixels. The vessel centerline is extracted after the preprocessing of vessel segmentation and optic disc （OD） localization. Then, a region of interest （ROI） is extracted around OD, and the most efficient features of each centerline pixel in ROI are selected from the local features, grey-level co-occurrence matrix （GLCM） features, and an adaptive local binary patten （A-LBP） feature by using a max-relevance and min-redundancy （mRMR） scheme. Finally, a feature-weighted K-nearest neighbor （FW-KNN） algorithm is used to classify the arterial-venous vessels. The experimental results on the DRIVE database and INSPIRE-AVR database achieve the high accuracy of 88.65% and 88.51% in ROI, respectively.

关键词： fundus image arterial-venous classification adaptive local binary patten(A-LBP) feature selection feature-weighted K-nearest neighbor(FW-KNN)

Boosting sulfur redox kinetics by a pentacenetetrone redox mediator for high-energy-density lithium-sulfur batteries

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Nano Research 2023年第6期16卷 8253-8259页

作者： Yan-Qi Peng Meng Zhao zi-Xian Chen qian Cheng Yiran liu Xi-Yao Li Yun-Wei Song Bo-Quan Li Jia-Qi Huang School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Lithium-sulfur(Li-S)battery is considered as a promising energy storage system due to its ultrahigh theoretical energy density of 2,600 Wh·kg^(−1).Redox mediation strategies have been proposed to promote the sluggish sulfur redox ***,the applicability of redox mediators in practical high-energy-density Li-S batteries has seldomly been *** this work,5,7,12,14-pentacenetetrone(PT)is proposed as an effective redox mediator to promote the sulfur redox kinetics under practical working conditions.A high initial specific discharge capacity of 993 mAh·g^(−1) is achieved at 0.1 C with high-sulfur-loading cathodes of 4.0 mgS·cm^(−2)and low electrolyte/sulfur(E/S)ratio of 5μL·mg_(S)^(−1).More importantly,practical Li-S pouch cells with the PT mediator realize an actual initial energy density of 344 Wh·kg^(−1)and cycle stably for 20 cycles wih a high capacity retention of 88%.This work proposes an effective redox mediator and further verifies the redox mediation strategy for practical high-energydensity Li-S batteries.

关键词： lithium-sulfur batteries lithium polysulfides redox mediation sulfur redox kinetics pouch cells

Tuning Acceptor Length in Photocatalytic Donor-Acceptor Conjugated Polymers for Efficient Solar-to-Hydrogen Energy Conversion

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Chinese Journal of Chemistry 2022年第20期40卷 2457-2467页

作者： qian Li Jia Li Wen-Rui Wang Li-Na liu zi-Wen Xu Guanghui Xie Jingjing Li Jianhua Yao Wei-Shi Li The Education Ministry Key Laboratory of Resource Chemistry Shanghai Normal UniversityShanghai200234 China CAS Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules ShanghaiInstitute of Organic ChemistryChinese Academy of Sciences345 Lingling RoadShanghai200032 China CAS Key laboratory of Energy Regulation Materials Shanghai Institute of Organic ChemistryChinese Academy of Sciences345 Lingling RoadShanghai200032 China Engineering Research Center of Zhengzhou for High Performance Organic Functional Materials Zhengzhou University of Technology6 Yingcai StreetHuiji DistrictZhengzhouHenan450044 China

The development of conjugated polymer photocatalysts for efficient solar-to-hydrogen energy conversion is highly desirable for the sustainability of our *** the construction of donor-acceptor(D-A)structure in conjugated polymer photocatalysts for solar-to-hydrogen energy conversion has been well documented,less attention has been paid on how large D and how large A units combined together could achieve the best ***,a series of D-A copolymers P(BDT-DBTSOx)(x=7,19,39,and 79)composed of a benzodithiophene(BDT)donor unit and an oligomeric dibenzo[b,d]thiophene sulfone(DBTSO)acceptor segment were synthesized and *** was found that the polymer photocatalytic stabilities under full-arc irradiation improved upon shortening the length of the acceptor *** visible light irradiation and in the presence of 3 wt%Pt cocatalyst,P(BDT-DBTSO79)displayed the best performance with an optimal hydrogen evolution rate of 119.3±5.8 mmol·g^(-1)·h^(-1).This is 1.4-fold as that of DBTSO homopolymer and 22.5-fold as that of BDT/DBTSO alternative copolymer,highlighting the importance of acceptor length in D-A structure for achieving high photocatalytic performance.

关键词： Photocatalysis Water splitting Solar-to-hydrogen energy conversion Conjugated polymers Donor-acceptor systems

Simultaneous determination of ten taste and odor compounds in drinking water by solid-phase microextraction combined with gas chromatography-mass spectrometry

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Journal of Environmental Sciences 2013年第11期25卷 2313-2323页

作者： Xichao Chen qian Luo Shengguang Yuan zi Wei Hanwen Song Donghong Wang zijian Wang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Taste and odor （T＆O） problems in drinking water frequently occur because of many compounds present in the water, of which trans-1,10-dimethyl-trans-9-decalol （geosrnin） and 2-methylisoborneol （MIB） are well-known. In this study, a fast and effective method was established for simultaneous determination of 10 T＆O compounds, including geosmin, MIB, 2,4,6-trichloroanisole （TCA）, 2-methylbenzofuran, 2-isopropyl-3-methoxypyrazine （IPMP）, 2-isobutyl-3-methoxypyrazine （IBMP）, cis-3-hexenyl acetate, trans,trans-2,4-heptadienal, trans, cis-2,6-nonadienal, and trans-2-decenal in water samples by headspace solid-phase microextraction （SPME） coupled with gas chromatography-mass spectrometry. An orthogonal array experimental design was used to optimize the effects of SPME fiber, extraction temperature, stirring rate, NaC1 content, extraction time, and desorption time. The limits of detection ranged from 0.1 to 73 ng/L were lower than or close to the odor threshold concentrations （OTCs）. All the 10 T＆O compounds were detected in the 14 water samples including surface water, treatment process water and tap water, taken from a waterworks in Lianyungang City, China. MIB and geosmin were detected in most samples at low concentration. Six T＆O compounds （IPMP, IBMP, trans,cis-2,6-nonadienal, 2-methylbenzofuran, trans-2-decenal, and TCA） were effectively decreased in water treatment process （sedimentation and filtration） that is different from cis-3-hexenyl acetate, MIB and geosmin. It is noted that the TCA concentrations at 15.9-122.3 ng/L and the trans,cis-2,6-nonadienal concentrations at 79.9-190.1 ng/L were over 10 times higher than their OTCs in tap water. The variation of the analytes in the all water samples, especially distribution system indicated that distribution system cannot be ignored as a T＆O compounds source.

关键词： taste and odor compound drinking water SPME-GC,rMS geosmin 2,4,6-trichloroanisole