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婴幼儿护肤品中违禁激素丙酸氯倍他索的荧光渐变型比色分析

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光谱学与光谱分析 2024年第6期44卷 1636-1639页

作者：许春华张惠煊孙毓唐楷臻徐银娟赵媛江南大学化学与材料工程学院合成与生物胶体教育部重点实验室江苏无锡214122

丙酸氯倍他索(CP)是一种糖皮质激素,可用于治疗湿疹、银屑病等皮肤病。婴幼儿长期频繁使用含CP的护肤品可能会导致严重的健康隐患。CP属化妆品禁添加组分,急需开发一种快速、简单护肤品中违禁激素CP的检测方法。通过橙色发光全无机钙钛... 详细信息

丙酸氯倍他索(CP)是一种糖皮质激素,可用于治疗湿疹、银屑病等皮肤病。婴幼儿长期频繁使用含CP的护肤品可能会导致严重的健康隐患。CP属化妆品禁添加组分,急需开发一种快速、简单护肤品中违禁激素CP的检测方法。通过橙色发光全无机钙钛矿量子点(CsPbBr 1.5 I 1.5 QDs)和CP之间发生的卤素交换反应,荧光信号发生蓝移,偏移波长与CP浓度之间呈良好的线性关系,实现婴幼儿护肤品中CP含量的快速检测,检出限为0.2 mmol·L^(-1),检测时间为10 min。开发了用于婴幼儿护肤品中CP检测的荧光比色卡,可快速、准确、简便地用于婴幼儿护肤品中CP含量的检测。

关键词：荧光光谱婴幼儿护肤品丙酸氯倍他索全无机钙钛矿量子点荧光比色分析

SmI_2-promoted imino-Reformatsky reaction for facile synthesis of enantioenriched β-amino acid esters

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Science China Chemistry 2011年第1期54卷 61-65页

作者： WANG Li SHEN chun xu Ming-hua Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 201203 China

A facile and efficient method for the stereoselective synthesis of β-amino acid esters via SmI2-promoted imino-Reformatsky reaction is *** addition of tert-butyl bromoacetate to N-tert-butanesulfinyl aldimines afforded β-amino acid esters in moderate to high yields with excellent *** synthetic utilities of the tert-butyl β-amino acid esters were expanded by the preparation of β-lactams and 3-aminoindan-1-ones derivatives.

关键词： β-amino acid ester samarium diiodide N-tert-butanesulfinyl imine Reformatsky reaction β-lactam 3-aminoindan-1-one asymmetric synthesis

济南市免疫预防工作人员对免疫规划疫苗接种程序的认知现况调查

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现代预防医学 2024年第11期51卷 2024-2029页

作者：徐颖许春华刘晓雪马永胜李传彬王琼赵建云济南市疾病预防控制中心免疫预防所中国疾病预防控制中心免疫规划中心

目的系统了解济南市免疫预防专业人员对《国家免疫规划疫苗儿童免疫程序及说明（2021年版）》中相关接种指导意见的认知情况，为提供更有针对性的技术指导和更好地完善儿童免疫程序和指导原则提供参考。方法于2022年9月对济南市的区... 详细信息

目的系统了解济南市免疫预防专业人员对《国家免疫规划疫苗儿童免疫程序及说明（2021年版）》中相关接种指导意见的认知情况，为提供更有针对性的技术指导和更好地完善儿童免疫程序和指导原则提供参考。方法于2022年9月对济南市的区县疾病预防控制中心（简称疾控中心）15名免疫预防技术骨干及423名在接种单位（含产科接种室）从事预检、接种的工作人员进行问卷调查，用Excel 2010和SPSS 18.0软件对调查数据进行描述性分析、χ2检验和多因素logistic回归分析。以15名疾控中心人员对免疫程序总知识、特殊健康状态儿童接种知识和疫苗同时接种知识的回答正确率为标准计算调查对象相应知识的知晓率。结果 438名调查对象对免疫程序总知识、特殊健康状态儿童接种知识和疫苗同时接种知识的知晓率分别为29.91%、23.29%和48.63%。多因素logistic回归分析结果显示，文化程度(OR=1.88,95%CI:1.13～3.12）、预防接种工作年限（OR=1.49,95%CI:1.01～2.22）和执业资格类别（OR=0.25,95%CI:0.068～0.88）是调查对象免疫程序总知晓率的影响因素。文化程度（OR=3.01,95%CI:1.63～5.57）和专业（OR=0.24,95%CI:0.075～0.78）是调查对象特殊健康状态儿童接种知晓率的影响因素。仅性别（OR=0.37,95%CI:0.16～0.86）是调查对象疫苗同时接种知识知晓率的影响因素。结论济南市预防接种门诊工作人员对于免疫程序的认知水平，包括对于特殊健康状态儿童接种以及疫苗同时接种知识的把握尚待进一步提高。建议合理增加侧重相关知识的预防接种专业技术培训，建议进一步完善和细化有关特殊健康状态儿童预防接种以及疫苗同时接种相关工作指南或指导性文件。

关键词：免疫规划疫苗免疫程序认知

Coagulation effect and floc properties of polyferric silicate sulphate and polyferric sulphate in the Yellow River water treatment

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Science China Chemistry 2010年第3期53卷 663-669页

作者： Cao, Bai Chuan Gao, Bao Yu Yue, Qin Yan Fu, Ying xu, chun hua Shandong Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and Engineering Shandong University Jinan 250100 China School of Civil and Architecture Jinan University Jinan 250022 China

Two inorganic polymer coagulants,polyferric silicate sulphate(PFSS) and polyferric sulphate(PFS),were comparatively evaluated in the Yellow River water *** removal efficiency of turbidity and UV254 were investigated,and the zeta potential was *** online laser scatter instrument was used to determine the size distribution of flocs formed in the coagulation *** with PFS,PFSS forms flocs with higher growth rates and larger *** formed flocs were exposed to a series of shear forces,and the floc strength was measured from the relationship between the applied shear speed and the resulting floc *** flocs formed by PFSS had a higher *** floc breakage(expressed as breakage factor,Bf) and re-growth ability(expressed as breakage factor,Rf) under different shear forces and different shear periods were investigated,and it was found that larger Bf and Rf appeared after exposure to stronger shear force and longer shear *** the same shear condition,the flocs formed by PFSS showed a larger Bf while the flocs formed by PFS had better re-growth ability.

关键词： ferric based inorganic polymer coagulants the Yellow River water floc growth floc strength floc breakage and re-growth

Temperature and stress fields of multi-track laser cladding

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Transactions of Nonferrous Metals Society of China 2009年第S02期19卷 495-501页

作者： ZHAO Hong-yun ZHANG Hong-tao xu chun-hua YANG Xian-qun School of Materials Science and Engineering Harbin Institute of Technology at WeihaiWeihai 264209China

Based on genetic algorithm and neural network algorithm,the finite element analyses on the temperature fields and stress fields of multi-track laser cladding were carried out by using the ANSYS *** results show that,in the multi-track cladding process,the temperature field ellipse leans to the cladding formed,and the front cladding has preheating function on the following *** cladding,the longitudinal stress is the largest,the lateral stress is the second,and the thickness direction stress is the *** center of the cladding is in the tensile stress *** longitudinal tensile stress is higher than the lateral or thickness direction stress by several times,and the tensile stress achieves the maximum at the area of joint between the cladding and ***,it is inferred that transversal crack is the most main crack form in multi-track laser ***,the joint between cladding and substrate is the crack sensitive area,and this is consistent with the actual experiments.

关键词： finite element analysis multi-track cladding stress field transversal crack

Damage and deterioration mechanism and curing technique of concrete structure in main coal cleaning plants

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Mining Science and Technology 2009年第6期19卷 750-755页

作者： LV Heng-lin ZHAO Cheng-ming SONG Lei MA Ying xu chun-hua School of Architecture and Civil Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221116 China State Key Laboratory for Geomechanics and Deep Underground Engineering Xuzhou Jiangsu 221008 China Wuhan Design ＆ Research Institute of Sinocoal International Engineering Group Wuhan Hubei 430064 China

Concrete structures in main coal cleaning plants have been rebuilt and reinforced in the coal mines of the Shanghai Datun Energy Sources Co. Ltd., the first colliery of the Pingdingshan Coal Co. Ltd. and the Sanhejian mine of the xuzhou Mining Group Co. Ltd. In these projects, the operating environment and reliability of concrete structures in the main plants of the three companies were investigated and the safety of the structures inspected. Qualitative and quantitative analyses were made on the special natural, technological and mechanical environments around the structures. On the basis of these analyses, we discuss the long-term, combined actions of the harsh natural (corrosive gases, liquids and solids) and mechanical environments on concrete structures and further investigated the damage and deteriorating mechanisms and curing techniques of concrete structures in the main coal cleaning plants. Our study can provide a theoretical basis for ensuring the reliability of concrete structures in main coal cleaning plants.

关键词： main coal cleaning plants concrete structure operating environment reliability detection and inspection damage anddeteriorating mechanisms curing technique

Aldehyde oxidase mediated enantioselective metabolic health risk of dinotefuran

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Science China Chemistry 2024年第6期67卷 2079-2091页

作者： Liwei xu Xinxin xu hua Kuang Chuanlai xu Xiaoling Wu State Key Laboratory of Food Science and Resources Jiangnan UniversityWuxi214122China International Joint Research Laboratory for Biointerface and Biodetection and School of Food Science and Technology Jiangnan UniversityWuxi214122China Collaborative Innovation center of Food Safety and Quality Control in Jiangsu Province Jiangnan UniversityWuxi214122China

Chiral pollutants often pose significant differential environmental health *** this study,the biotransformation of chiral dinotefuran(DIN)and its enantioselective metabolic toxicity mechanisms have been systemically ***,reversedphase chromatography-high resolution mass spectrometry was developed to quantify the content of DIN R/S chiral enantiomer with pg level sensitivity,revealing a lower elimination rate constant(K_(e))of S-DIN(0.730 h^(-1))than R-DIN(0.746 h^(-1)).Secondly,the interaction mechanism between DIN metabolism and important endogenous bioactive molecules,such as aldehyde oxidase(AOX)and neurotransmitters,was *** DIN nitro-group was converted into a guanidine group by the reducing site of nearby flavin adenine dinucleotide(FAD)in AOX with the preferred higher affinity of ***,the endogenous tryptophan(Trp)aldehyde metabolic intermediate,5-hydroxyindoleacetaldehyde(5-HIAL),provides a persistent electron donor for DIN reduction via the oxidation-catalyzed site in AOX,resulting in remarkable up-regulation of monoamine neurotransmitters such as serotonin and ***,the higher level of neurotransmitters further mediated dysregulation of oxylipin homeostasis via the serotonergic pathway,where S-DIN exhibited more pronounced liver lipid damage and environmental health risk with the accumulated lipid biomarkers,oxidized triglyceride(OxTG)and oxidized sphingomyelin(OxSM).This study elucidates the AOX-mediated enantioselectivity metabolic pathway of DIN,providing a new analytical method for chiral pollutants and paves the way for their health risk assessments.

关键词： neonicotinoid dinotefuran enantiomer aldehyde oxidase metabolomics health risk

Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

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Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： Shi-Liang xu Ying-Nan Zhao Yao Yu Qi Yang Li-hua Na Heng Liu chun-Yu Zhang xue-Quan Zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in *** catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of ***,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene *** characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer *** resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity

Optimal investment based on relative performance and weighted utility

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 328-342页

作者： WANG Lei DONG Ying-hui hua chun-rong Department of Mathematics Suzhou University of Science and TechnologySuzhou 215009China Changshu Institute of Technology Changshu 215500China

This paper studies the optimal portfolio allocation of a fund manager when he bases decisions on both the absolute level of terminal relative performance and the change value of terminal relative performance comparison to a predefined reference point. We find the optimal investment strategy by maximizing a weighted average utility of a concave utility and an Sshaped utility via a concavification technique and the martingale method. Numerical results are carried out to show the impact of the extent to which the manager pays attention to the change of relative performance related to the reference point on the optimal terminal relative performance.

关键词： relative performance weighted utility S-shaped utility concavification