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Metrological traceable calibration of organic carbon and elemental carbon based on laboratory-generated reference materials

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Journal of Environmental Sciences 2025年第3期149卷 524-534页

作者： Yue Liu Junjie Liu ji xiao jing Ye Lixu Guo Caiqing Yan Center for Environmental Metrology National Institute of Metrology ChinaBeijing 100029China College of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024China Environment Research Institute Shandong UniversityQingdao 266237China

Carbonaceous aerosol,including organic carbon(OC)and elemental carbon(EC),has significant influence on human health,air quality and climate *** measurement of carbonaceous aerosol is essential to reduce the uncertainty of radiative forcing estimation and source *** accurate separation of OC and EC is controversial due to the charring of ***,the development of reference materials(RM)for the validation of OC/EC separation is an important basis for further *** RMs were mainly based on ambient air sampling,which could not provide traceability of OC and EC *** develop traceable RMs with known OC/EC contents,our study applied an improved aerosol generation and mixing technique,providing uniform deposition of particles on quartz *** generate OC aerosol with similar pyrolytic property of ambient aerosol,both water soluble organic carbon(WSOC)and water insoluble organic carbon(WIOC)were used,and amorphous carbon was selected for EC *** RMs were analyzed using different *** homogeneity within the filter was validated,reaching below 2%.The long-term stability of RMs has been validated with RSD ranged from 1.7%–3.2%.Good correlationwas observed between nominal concentration of RMswithmeasured concentration by two protocols,while the difference of EC concentration was within 20%.The results indicated that the newly developed RMs were acceptable for the calibration of OC and EC,which could improve the accuracy of carbonaceous aerosol ***,the laboratory-generated EC-RMs could be suitable for the calibration of equivalent BC concentration by Aethalometers.

关键词： Carbonaceous aerosol Split point Reference material Laboratory-generated Traceability

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县级政府推进乡村振兴工作质量提升研究:基于政府全面质量管理的行动框架

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安徽农业科学 2025年第1期53卷 245-249页

作者：纪晓光华侨大学政治与公共管理学院福建泉州362011

政府全面质量管理是一种基于管理主义和技术理性形成的,以质量为中心,以“顾客”需求为导向、以战略管理为依托,以全员参与为基础、以过程管理为重点、以信息技术为支撑的政府管理模式,能够有效促进政府治理质量提升。县域是乡村振兴的... 详细信息

政府全面质量管理是一种基于管理主义和技术理性形成的,以质量为中心,以“顾客”需求为导向、以战略管理为依托,以全员参与为基础、以过程管理为重点、以信息技术为支撑的政府管理模式,能够有效促进政府治理质量提升。县域是乡村振兴的主战场,促进乡村振兴是当代中国县级政府的使命所指、职责所在,其相关工作质量是县级政府治理质量的重要组成部分。然而由于部分县级政府“城市中心主义”的治理价值取向、对乡村振兴政策执行不力以及错配城乡社会发展资源等原因,使得当下中国县域乡村振兴呈现质量参差不齐的局面。为了打破这一局面,促进县域乡村振兴质量的全面提升,急需按照政府全面质量管理的行动框架,对县级政府乡村振兴行为进行重塑。

关键词：县级政府政府全面质量管理乡村振兴治理质量

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2016~2021年秋冬季邯郸市PM_(2.5)污染特征与来源对比

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环境科学 2025年第1期46卷 591-602页

作者：马心怡纪晓腾马博健田宇婷朱浩牛红亚河北工程大学地球科学与工程学院邯郸056038 河北先进环保产业创新中心有限公司石家庄050000

2018年国务院发布《打赢蓝天保卫战三年行动计划》(蓝天保卫战),为研究邯郸市秋冬季在蓝天保卫战前期(第一阶段)、中期(第二阶段)和后期(第三阶段)PM_(2.5)污染特征与来源,于2016~2021年秋冬季采集PM_(2.5)样品,基于8种水溶性离子、EC... 详细信息

2018年国务院发布《打赢蓝天保卫战三年行动计划》(蓝天保卫战),为研究邯郸市秋冬季在蓝天保卫战前期(第一阶段)、中期(第二阶段)和后期(第三阶段)PM_(2.5)污染特征与来源,于2016~2021年秋冬季采集PM_(2.5)样品,基于8种水溶性离子、EC和OC浓度数据,通过正定矩阵因子分解模型(PMF)、后向轨迹和潜在源贡献因子(PSCF)分析法对其进行来源解析.结果表明,近几年PM_(2.5)年度和秋冬季浓度均值整体呈降低趋势,采样期间3个阶段中水溶性离子(WSIIs)和总碳(TC)浓度也均逐阶段下降,第三阶段(52.70μg·m^(-3)和17.17μg·m^(-3))相较第一阶段(80.23μg·m^(-3)和46.89μg·m^(-3))浓度分别下降了34.31%和63.38%,但其中二次组分占比的变化规律不同.3个阶段中SNA浓度分别占PM_(2.5)总浓度的46.79%、48.86%和43.22%;SOC在PM_(2.5)中的占比为12.43%、14.05%和6.81%,占比均先上升后下降. 3个阶段中SOR均值分别为0.34、0.37和0.36,NOR为0.23、0.28和0.28,说明蓝天保卫战期间二次转化程度最高.从污染物来源看,邯郸市PM_(2.5)主要来源为二次源、燃烧源、工业源、交通源和扬尘源,蓝天保卫战期间一次排放有所下降(主要是燃烧源与工业源),结束后一次排放上升,其中工业源贡献率从12.17%上升到20.20%,且经后向轨迹聚类分析可知第二阶段二次源贡献率明显高于其他阶段,尤其是来自山东和陕西的气流.潜在源分析表明3个阶段WPSCF高值区域均主要集中在河北南部和河南北部,不同的是第三阶段相比第一阶段的潜在源区由山西中部向南部转移.这项工作证实了蓝天保卫战的环境效益明显,随着蓝天保卫战的开展,二次组分贡献突出;蓝天保卫战结束之后,二次组分占比下降,一次组分的影响增大,应加强对直接排放的管控.

关键词： PM_(2.5) 蓝天保卫战水溶性离子碳质气溶胶来源解析

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魔芋胶提高挤压山药淀粉中抗性淀粉含量的工艺研究

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中国调味品 2025年第1期50卷 41-45,91页

作者：郝梦爽冀晓龙史苗苗闫溢哲郑州轻工业大学食品与生物工程学院郑州450001

抗性淀粉作为一种健康成分,对人体健康有着诸多积极影响,包括控制血糖和胰岛素水平、促进肠道健康、控制体重。挤压技术作为一种高温、短时、连续的多功能热机械技术,集混合、搅拌、剪切、加热、熟化和成型于一体,且具有高效环保的特点... 详细信息

抗性淀粉作为一种健康成分,对人体健康有着诸多积极影响,包括控制血糖和胰岛素水平、促进肠道健康、控制体重。挤压技术作为一种高温、短时、连续的多功能热机械技术,集混合、搅拌、剪切、加热、熟化和成型于一体,且具有高效环保的特点。水分含量、挤压温度和螺杆转速是影响挤压效果的重要因素。该研究以抗性淀粉(RS)含量为响应值,采用Box-Behnken响应面分析法,通过单因素实验和响应面实验确定了水分含量、挤压温度和螺杆转速的最佳组合。研究结果显示,在山药淀粉和魔芋胶的挤压过程中,水分含量为30%、挤压温度为90℃、螺杆转速为180 r/min时,抗性淀粉含量高达42.58%。该研究为山药淀粉的利用和产品开发提供了重要的理论依据。

关键词：魔芋胶山药淀粉抗性淀粉挤压技术

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Removing Impurity of cBN Crystal Prepared at High Pressure and High Temperature

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Chinese Physics Letters 2012年第3期29卷 224-226页

作者： ji xiao-Rui YANG xiao-Hong Department of Preparatory Course Shenyang Institute of EngineeringShenyang 110136

The black cubic boron nitride(cBN)single crystal is synthesized by using hBN-LiH and hBN-Li_(3)N-B as the raw materials at high temperature and high pressure(HTHP).The colors of the cBN crystal synthesized in an hBN-Li_(3)N-B system vary from transparent yellow,half-transparent and then opaque black with the increasing B content in the raw *** is worth noting that a trigonal shadow is presented at the center of the cBN crystal synthesized in the hBN-Li_(3)N-B system but can not be found in the hBN-LiH *** the Raman spectrum,we find that the darkening and the trigonal shadow in the cBN crystal may be due to the presence of excess B *** above-mentioned phenomenon can be determined by removing impurity capacity and growth environment of the cBN crystal.

关键词： transparent removing Crystal

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Fine-needle aspiration cytology of liver diseases

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World Journal of Gastroenterology 1999年第2期5卷 7-9页

作者： ji xiao Long 解放军总医院北京

Ｕｌｔｒａｓｏｎｏｇｒａｐｈｙ，ＣＴａｎｄｍａｇｎｅｔｉｃｒｅｓｏｎａｎｃｅｈａｖｅｂｅｅｎｗｉｄｅｌｙｕｓｅｄｉｎｔｈｅｄｉａｇｎｏｓｉｓｏｆｌｉｖｅｒｄｉｓｅａｓｅｓｉｎｔｈｅｐａｓｔ２０ｙｅａｒｓ，ｂｕｔｔｈｅ... 详细信息

Ｕｌｔｒａｓｏｎｏｇｒａｐｈｙ，ＣＴａｎｄｍａｇｎｅｔｉｃｒｅｓｏｎａｎｃｅｈａｖｅｂｅｅｎｗｉｄｅｌｙｕｓｅｄｉｎｔｈｅｄｉａｇｎｏｓｉｓｏｆｌｉｖｅｒｄｉｓｅａｓｅｓｉｎｔｈｅｐａｓｔ２０ｙｅａｒｓ，ｂｕｔｔｈｅｆｉｎａｌｄｅｆｉｎｉｔｅｄｉａｇ...

关键词： biopsy,needle/cytology liver neoplasms/pathology

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Some additive results on Drazin inverse

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Applied Mathematics(A Journal of Chinese Universities) 2015年第4期30卷 479-490页

作者： LIU xiao-ji QIN xiao-lan Julio Benítez Faculty of Science Guangxi University for Nationalities Universidad Politécnica de Valencia Instituto de Matemática Multidisciplinar

In this paper, we investigate additive results of the Drazin inverse of elements in a ring R. Under the condition ab = ha, we show that a ＋ b is Drazin invertible if and only if aaD （a ＋ b） is Drazin invertible, where the superscript D means the Drazin inverse. Furthermore we find an expression of （a ＋ b）D. As an application we give some new representations for the Drazin inverse of a 2 × 2 block matrix.

关键词： Drazin inverse ring block matrix.

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Tree shrew (Tupaia belangeri)as a novel laboratory disease animal model

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Zoological Research 2017年第3期38卷 127-137页

作者： ji xiao Rong Liu Ce-Shi Chen Medical Faculty of Kunming University of Science and Technology Kunming Yunnan 650500 China Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences and Yunnan Province Kunming Institute of Zoology Chinese Academy of Sciences Kunming Yunnan 650223 China

The tree shrew （Tupaia belangeri） is a promising laboratory animal that possesses a closer genetic relationship to primates than to rodents. In addition, advantages such as small size, easy breeding, and rapid reproduction make the tree shrew an ideal subject for the study of human disease. Numerous tree shrew disease models have been generated in biological and medical studies in recent years. Here we summarize current tree shrew disease models, including models of infectious diseases, cancers, depressive disorders, drug addiction, myopia, metabolic diseases, and immune-related diseases. With the success of tree shrew transgenic technology, this species will be increasingly used in biological and medical studies in the future.

关键词： Tree shrew (Tupaia belangeri) Animal model Transgenic Disease

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Machine learning-based models for advanced fibrosis in non-alcoholic steatohepatitis patients: A cohort study

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World Journal of Gastroenterology 2025年第9期31卷 30-42页

作者： Xiong, Fei-Xiang Sun, Lei Zhang, Xue-jie Chen, jia-Liang Zhou, Yang ji, xiao-Min Meng, Pei-Pei Wu, Tong Wang, Xian-Bo Hou, Yi-Xin Center of Integrative Medicine Beijing Ditan Hospital Capital Medical University Beijing 100015 China Department of Pathology Beijing Ditan Hospital Beijing 100015 China

BACKGROUND The global prevalence of non-alcoholic steatohepatitis (NASH) and its associated risk of adverse outcomes, particularly in patients with advanced liver fibrosis, underscores the importance of early and accurate diagnosis. AIM To develop a machine learning-based diagnostic model for advanced liver fibrosis in NASH patients. METHODS A total of 749 patients who underwent liver biopsy at Beijing Ditan Hospital, Capital Medical University, between January 2010 and January 2020 were included. Patients were randomly divided into training (n = 522) and validation (n = 224) cohorts. Five machine learning models were applied to predict advanced liver fibrosis, with feature selection based on Shapley Additive Explanations (SHAP). The diagnostic performance of these models was compared to traditional scores such as the aspartate aminotransferase to platelet ratio index (APRI) and fibrosis index based on the 4 factors (FIB-4), using metrics including the area under the receiver operating characteristic curve (AUROC), decision curve analysis (DCA), and calibration curves. RESULTS The Extreme Gradient Boosting (XGBoost) model outperformed all other machine learning models, achieving an AUROC of 0.934 (95%CI: 0.914-0.955) in the training cohort and 0.917 (95%CI: 0.880-0.953) in the validation cohort (P < 0.001). Incorporating liver stiffness measurement into the model further improved its performance, with an AUROC of 0.977 (95%CI: 0.966-0.980) in the training cohort and 0.970 (95%CI: 0.950-0.990) in the validation cohort, significantly surpassing APRI and FIB-4 scores (P < 0.001). The XGBoost model also demonstrated superior clinical utility, as evidenced by DCA and calibration curve analysis in both cohorts. CONCLUSION The XGBoost model provides a highly accurate, non-invasive diagnosis of advanced liver fibrosis in NASH patients, outperforming traditional methods. An online tool based on this model has been developed to assist clinicians in evaluating the risk of adva

关键词： Advanced fibrosis Extreme Gradient Boosting Machine learning Non-alcoholic steatohepatitis Non-invasive

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Path Planning in Complex 3D Environments Using a Probabilistic Roadmap Method

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International Journal of Automation and computing 2013年第6期10卷 525-533页

作者： Fei Yan Yi-Sha Liu ji-Zhong xiao School of Control Science and Engineering Dalian University of Technology School of Information Science and Technology Dalian Maritime University Department of Electrical and Engineering The City CollegeCity University of New York

This paper presents a 3D path planning algorithm for an unmanned aerial vehicle （UAV） in complex environments. In this algorithm, the environments are divided into voxels by octree algorithm. In order to satisfy the safety requirement of the UAV, free space is represented by free voxels, which have enough space margin for the UAV to pass through. A bounding box array is created in the whole 3D space to evaluate the free voxel connectivity. The probabilistic roadmap method （PRM） is improved by random sampling in the bounding box array to ensure a more efficient distribution of roadmap nodes in 3D space. According to the connectivity evaluation, the roadmap is used to plan a feasible path by using A＊ algorithm. Experimental results indicate that the proposed algorithm is valid in complex 3D environments.

关键词： 3D path planning complex environment unmanned aerial vehicle (UAV) probabilistic roadmap methed (PRM) octree.

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