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Journal of Environmental Sciences 2005年第6期17卷 930-932页

作者： HUANG Min-jia jiang Gui-bin zhao Zong-shan State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Science Chinese Academy of SciencesBeijing 100085 China

Base on the previous work in laboratory, a novel polyaniline doped with polydimethylsiloxane coating was developed on a stainless steel wire for solid phase microextraction（SPME） by electroplating method. This electroplating method not only has advantages of ease preparation and simple equipments required, but also increases the lifetime of the SPME fiber. The composite fiber（polyaniline/ polydimethylsiloxane（PANI/PDMS）） was evaluated by analyzing n-tridecane, n-tetradecane and n-pentadecane in aqueous sample. The new fiber coating showed comprehensive abilities to extract alkanes compounds. The relative standard deviations were found to be 6.8%-10.33%.

关键词： solid phase microextraction stainless steel wires electroplating fiber preparation polyaniline/polydimethylsiloxane alkanes

土壤水分和种植密度对紫花苜蓿生物量分配的影响

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草业科学 2024年第9期41卷 2094-2103页

作者：蒋朝吴征江李春阳张振洲武文莉刘慧霞西北民族大学生命科学与工程学院甘肃兰州730000 甘南民族师范学院化学与生命科学系甘肃合作747000

为探寻生物量分配对不同土壤水分和种植密度互作的响应规律,为生产管理中通过种植密度和土壤含水量耦合管理来调控植物生物量分配,提高水分利用效率和植物生产力,完善植物适应环境因素的机制研究,本研究以紫花苜蓿(Medicago sativa)为材... 详细信息

为探寻生物量分配对不同土壤水分和种植密度互作的响应规律,为生产管理中通过种植密度和土壤含水量耦合管理来调控植物生物量分配,提高水分利用效率和植物生产力,完善植物适应环境因素的机制研究,本研究以紫花苜蓿(Medicago sativa)为材料,通过盆栽试验分析了不同土壤水分85%~90%(W_(1))、75%~80%(W_(2))、60%~65%(W_(3))、35%~40%(W_(4))的土壤饱和含水量和不同种植密度10(D_(1))、15(D_(2))、20(D_(3))株·盆^(−1)对紫花苜蓿生物量分配的影响。结果表明,土壤水分显著影响紫花苜蓿的叶生物量、茎生物量、单株地上生物量、地上生物量、地下生物量、根冠比(P<0.05),随土壤水分的减少,均呈先增加后降低趋势,峰值均出现在土壤水分含量为土壤饱和含水量的75%~80%时。种植密度显著影响紫花苜蓿单株地上生物量、地下生物量和根冠比(P<0.05),随种植密度增大,单株地上生物量呈先增高后降低趋势,种植密度为15株·盆^(−1)时,地下生物量和根冠比则呈增高趋势。土壤水分和种植密度互作只显著影响了紫花苜蓿的单株地上生物量(P<0.05),在土壤水分为土壤饱和含水量的75%~80%,种植密度为15株·盆^(−1)时,紫花苜蓿单株地上生物量有最大值,为5.00 g。这一结果说明紫花苜蓿可以通过调节地上、地下生物量的分配来适应土壤水分和种植密度条件,提高其水分利用效率和产量。

关键词：紫花苜蓿水分梯度密度梯度地上生物量地下生物量

Enhancing the ionic conductivity in a composite polymer electrolyte with ceramic nanoparticles anchored to charged polymer brushes

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Chinese Chemical Letters 2020年第3期31卷 831-835页

作者： Bintao zhao Xi Lu Qian Wang Jingfa Yang jiang zhao Henghui Zhou College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China Pulead Technology Industry Co.Ltd. Beijing 102200China Institute of Chemistry Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Polymer electrolytes a re essential for next-gene ration lithium batteries because of their excellent safety ***,low ionic conductivity is the main obstacle restricting their commercial *** with nanoparticles are a promising route to overcome this *** this work,lithium polystyrene sulfonate brushes(LiPSS)is anchored to silicon dioxide nanoparticles with chemical bonding using atom transfer radial polymerization(SI-ATRP).The composite polymer electrolytes are made by mixing vinylene carbonate and nanoparticles via a facile in situ polymerization *** ionic conductivity of composite polymer electrolytes is improved to 7.2×10^-4 S/cm at room temperature,which is attributed to the low degree of crystallinity of polymer electrolyte and the fast ion transport on the surfaces of polymer brush layers that act as a conductive *** composite polymer electrolytes show a wide electrochemical window of approximately 4.5 V ***^+/Li and excellent cycling performance retention of approximately 95%after 100 cycles at ambient *** results also prove that surface groups of ceramic na noparticles are an important way to increase the electrochemical properties of composite polymer electrolytes.

关键词： Polymer electrolyte Polymer brushes Solid batteries Nanoparticles Composite electrolyte

难治性癫痫儿童血浆激肽释放酶、组织蛋白酶B的表达及其临床意义

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四川解剖学杂志 2024年第1期32卷 53-56页

作者：刘竹清姜亚召刘园河南中医药大学第五临床医学院(郑州人民医院)儿科郑州450000 河南省第二人民医院检验科郑州450000 郑州大学基础医学院郑州450000

目的:探讨难治性癫痫儿童血浆激肽释放酶(KLK)、组织蛋白酶B(catB)表达及其临床意义.方法:选取2017年3月至2019年3月河南中医药大学第五临床医学院收治的难治性癫痫患儿43例为研究对象,纳入研究组.选择同期在本院治疗的治疗有效癫痫患儿... 详细信息

目的:探讨难治性癫痫儿童血浆激肽释放酶(KLK)、组织蛋白酶B(catB)表达及其临床意义.方法:选取2017年3月至2019年3月河南中医药大学第五临床医学院收治的难治性癫痫患儿43例为研究对象,纳入研究组.选择同期在本院治疗的治疗有效癫痫患儿,同期在本院体检的健康儿童作为对照,分别纳入治疗有效组(n=35)及对照组(n=50).①对3组受试儿血浆KLK、catB,白细胞介素(IL)-6、IL-8、肿瘤坏死因子(TNF)-α水平分别进行统计学分析.②分析研究组患儿血浆KLK、catB水平,分别与其血浆IL-8、IL-6、TNF-α水平的相关关系.③受试者工作特征(ROC)曲线的曲线下面积(AUC),对难治性癫痫的诊断截断值、诊断灵敏度及特异度.④采取多因素非条件Logistic回归分析难治性癫痫临床诊断的独立影响因素.结果:①研究组患儿血浆KLK、catB、IL-6、IL-8、TNF-α水平,均显著高于对照组、治疗有效组,并且差异均有统计学意义(P<0.05).②研究组患儿血浆KLK、catB水平与其IL-6、IL-8、TNF-α水平,均呈正相关关系(r=0.625、0.628、0.657,0.634、0.619、0.664,P<0.05).③血浆KLK、catB水平ROC曲线的AUC分别为0.889、0.856,对难治性癫痫的诊断截断值分别为3.99 U/mL、3.66 U/mL,二者单独诊断难治性癫痫的灵敏度分别为72.10%、72.10%,特异度分别为92.00%、94.00%;二者联合诊断的AUC为0.950,灵敏度为86.00%,特异度为90.70%.④血浆KLK高表达(OR=2.652,95%CI:1.668~4.218,P<0.05),以及catB高表达(OR=2.635,95%CI:1.704~4.075,P<0.05),均是导致患儿发生难治性癫痫的独立危险因素.结论:难治性癫痫儿童血浆KLK、catB水平高表达,对难治性癫痫患儿的临床诊断具有重要参考价值.

关键词：难治性癫痫激肽释放酶组织蛋白酶B

基于机器学习算法的农村老年癌症患者预后分类模型的构建与验证

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中国实用护理杂志 2024年第21期40卷 1661-1670页

作者：常利杨志华赵将岳勤沈红红樊春秀谢娟陕西省肿瘤医院护理部西安710061 府谷县人民医院护理部榆林719400 汉阴县人民医院护理部安康725100 蒲城县医院护理部渭南715500

目的基于机器学习算法构建陕西省农村老年癌症患者预后分类模型,对其效能进行验证,为患者预后早期识别和干预治疗提供参考。方法采用多中心、横断面调查法,便利抽样法选取2022年7—8月在陕西省9所不同医疗机构(陕西省肿瘤医院及其专科... 详细信息

目的基于机器学习算法构建陕西省农村老年癌症患者预后分类模型,对其效能进行验证,为患者预后早期识别和干预治疗提供参考。方法采用多中心、横断面调查法,便利抽样法选取2022年7—8月在陕西省9所不同医疗机构(陕西省肿瘤医院及其专科联盟成员单位)住院的617例农村老年癌症患者为研究对象,建立农村老年癌症患者的"基本资料""自理能力""症状""综合需求"和"生命质量"变量数据库,开展机器学习和统计学分析,探索农村老年癌症患者的预后重要特征性指标,构建农村老年癌症患者的预后分类模型并进行验证。结果最终回收有效问卷597份。597例患者中,男207例,女390例,年龄(69.56±8.84)岁。聚类探索结果示,农村老年癌症患者预后分为好、中、差3个类别。好、中、差3个类别的受试者工作特征曲线下面积分别为0.84、0.79、0.69。特征探索结果示,"是否伴有转移""苦恼""悲伤""身体麻木""进食""走路""疲劳""健忘""生活乐趣"及"与他人关系"10个指标是农村老年癌症患者预后评价的重要特征性指标,农村老年癌症患者预后评价的10个重要特征性指标的3个类别比较差异均有统计学意义(χ^(2)=21.07,H值为18.51~144.38,均P<0.01);"综合需求""生命质量""自理能力""症状"的3个分类比较差异均有统计学意义(H值为519.40、40.80、103.69,均P<0.01)。结论基于机器学习算法构建并验证农村老年癌症患者预后分类模型,可以有效探索农村老年癌症患者预后评价的重要特征性指标及预后分类,为临床医护人员制订个体化方案提供依据和指导。

关键词：农村老年人癌症重要特征预后机器学习

Research on vacuum drying process and internal heat conduction of Li-ion battery core

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Theoretical & Applied Mechanics Letters 2019年第2期9卷 120-129页

作者： zhao jiang Fanghua zhao Yuming Guan Zizhen Qiu School of Mechanical Engineering Hebei University of Technology China Information Center for Lithium Energy Battery Equipment Hebei University of Technology

In this research, an innovative cylindrical automatic battery core oven was designed to avoid the structural deformation that frequently occurs in traditional ovens. The oven could be automatically connected with the electrolyte injection process after baking, achieving improvement in a battery's baking consistency. This contributed to the feasibility of studying the internal heat conduction process of batch battery cores during actual baking processes. A mathematical model of a certain plate battery cell during the baking process was established. The simulation results of the temperature change inside the battery core during the baking process were consistent with the calculation results of the mathematical model. The temperature distribution at each point inside the battery core could be fitted through the thermal conductivity at different temperatures and the temperature distribution between the layers of the battery ***, based on the thermodynamic balance energy conservation method, the relationship between the temperature change inside the battery core and the entire baking process was established. A feasible algorithm for studying the thermal conduction of complex material and internal structure objects in the baking process was obtained.

关键词： Heat and mass transfer Vacuum drying Li-ion battery CFD

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基于机器学习算法的心力衰竭预测模型

基础医学与临床 2024年第6期44卷 845-852页

作者：胡川丽贺晓松赵江李华陆军军医大学第二附属医院麻醉科重庆400037 重庆工程学院大数据与人工智能学院重庆400037 陆军军医大学第二附属医院泌尿科重庆400037

目的4种机器学习算法构建心力衰竭风险预测模型,为早期发现病患和治疗干预提供理论支撑。方法通过对Kaggle社区上发布的心力衰竭数据集预处理后,使用特征选择筛选出与心衰的相关因素作为预测指标,选择逻辑回归、决策树、AdaBoost、XGBoo... 详细信息

目的4种机器学习算法构建心力衰竭风险预测模型,为早期发现病患和治疗干预提供理论支撑。方法通过对Kaggle社区上发布的心力衰竭数据集预处理后,使用特征选择筛选出与心衰的相关因素作为预测指标,选择逻辑回归、决策树、AdaBoost、XGBoost 4种机器学习算法建立预测模型。对其准确率、精准率、召回率、F1-Score、ROC曲线下面积(AUC)进行对比分析,以验证模型性能。结果研究分析了918例心衰患者的11种特征,筛选出10个特征因子纳入建模。经网格搜索方法超参数调优后,XGBoost模型表现最优,准确率、精准率、召回率、f1_score、AUC值分别为87.5%、90.38%、89.71%、90.04%、0.93。另外,数据分析显示运动ST段坡度、运动性心绞痛、胸痛类型、年龄为心力衰竭的主要影响因子。结论XGBoost模型对心力衰竭预测性能最佳,机器学习算法能为心力衰竭的早期防控及诊断提供参考依据。

关键词：心力衰竭机器学习预测

Compound Ceramic Coatings Grown by Micro-plasma Oxidation on Ti-6Al-4V Alloy

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Chinese Journal of Aeronautics 2006年第B12期19卷 126-129页

作者： XUE Wei YAO Zhong-ping jiang zhao-hua Department of Applied Chemistry Harbin Institute of Technology Harbin 150001 China Heilongjiang Provincial Institute of Measurement and Verification Harbin 150036 China

Compound ceramics coatings on the Ti-6Al-4V alloy were prepared by the direct current micro-plasma oxidation （MPO） in NaAlO2 solution. The composition and morphology of the coatings were studied with the X-ray diffraction （XRD） and the scanning electron microscopy （SEM）, respectively. Inductively coupled plasma atomic emission spectrometer technique was used to analyze the solution features of Ti-6Al-4V alloy in the process of preparation. The results reveal that Al2TiO5 forms in the coatings at the initial stages of MPO reaction, and its content changes rapidly with the reaction continuing： after 20 min, the ceramics coatings are composed of α-Al2O3, 7-Al2O3 and Al2TiO5, but after 40 min, its main composition is of α-Al2O3. The content of Ti in the solution will increase when the MPO time extends, and as will Al in the anode area until, after 30 min, it reaches the maximum and keeps constant from then on. Both substrata of Ti and Al in the electrolyte join the MPO reaction at the initial stage, where the formation of Al2TiO5 happens; but as the MPO reaction prolongs, more and more Al in the electrolyte will take part in the reaction, leading to the appearance of a large amount ofAl2O3.

关键词： micro-plasma oxidation ceramic coatings composition inductively coupled plasma atomic emission spectrometer technique (ICP-AES)

Control and dynamics analysis for miniature autogyro and compound autogyro

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Science China(Information Sciences) 2019年第1期62卷 64-66页

作者： Zhihao CAI Ningjun LIU jiang zhao Yingxun WANG School of Automation Science and Electrical Engineering Beihang University

Dear editor,An autogyro is a type of aircraft achieving effective low-speed flight and short take-off and landing performance. A compound autogyro is a "pure" autogyro, designed with additional fixed wings. Its rotor ... 详细信息

关键词： Control and dynamics analysis for miniature autogyro and compound autogyro Figure

Optimization of Thermoelectric Microwave Power Sensors Based on Thin-Membrane Structure

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Chinese Journal of Electronics 2015年第4期24卷 884-888页

作者： WANG Debo GAO Bo zhao jiang ZHANG Yi GUO Yanyan Nanjing University of Posts and Telecommunication

In this work, the thermal conduction property of thermoelectric microwave power sensors is researched. The fabrication of the thermoelectric microwave power sensor consists of a front side and a back side processing using Ga As Monolithic microwave integrated circuit(MMIC) process and MEMS technology. An isolation structure on the front side is designed to prevent the thermal conduction from the resistor to the Coplanar waveguide(CPW). A thin-membrane on the back side is designed to prevent the thermal conduction from the resistor to the substrate. For the microwave power sensor without an isolation structure, the sensitivity is about 0.138, 0.136,0.132, 0.115 and 0.111 m V/m W at 8, 9, 10, 11 and 12 GHz,respectively. For the microwave power sensor with an isolation structure, the sensitivity is about 0.142, 0.139, 0.135,0.117 and 0.115 m V/m W at 8, 9, 10, 11 and 12 GHz, respectively. As a result, the higher thermal conduction efficiency and the higher sensitivity are obtained for the optimized thermoelectric microwave power sensors.

关键词： Thermal conduction Power sensor Ga As Monolithic microwave integrated circuit(MMIC) Microelectromechanical systems(MEMS)