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暨南学报（哲学社会科学版） 2009年第2期31卷 236-240页

作者：周聿峨余彬暨南大学国际关系学系广东广州510630

东南亚华人的地域认同,是华人研究的课题之一。按照其历史形态的演化过程,可以从心理地理空间认同、政治地理空间认同和跨国社会地理空间认同这个三重性维度进行考察。

关键词：东南亚华人地域认同全球化

Stochastic Resonance of a Periodically Driven Bistable System with Two Different Kinds of Time Delays

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Communications in Theoretical Physics 2009年第11期52卷 871-875页

作者： ZeNG Chun-Hua zhou Xiao-Feng ZeNG Qin-Huang YU Huan LI Zhi-Xiong Faculty of Science Kunming University of Science and Technology Kunming 650093 China Department of Physics Qujing Normal University Qujing 655000 China Department of Physics Yunnan University Kunming 650091 China

In this paper, we study the phenomenon of stochastic resonance （SR） in a periodically driven bistable system with correlations between multiplicative and additive white noise terms when there, are two different kinds of time delays existed in the deterministic and fluctuating forces, respectively. Using the small time delay approximation and the theory of signal-to-noise ratio （SNR） in the adiabatic limit, the expression of SNR is obtained. The effects of the delay time T in the deterministic force, and the delay time 8 in the fluctuating force on SNR are discussed. Based on the numerical computation, it is found that：（i） There appears a reentrant transition between one peak and two peaks and then to one peak again in the curve of SNR when the value of the time delay θ is increased. （ii） SR can be realized by tuning the time delay T or 8 with fixed noise, i.e., delay-induced stochastic resonance （DSR） exists.

关键词： stochastic resonance time delays bistable system

New flame retardant epoxy resins based on cyclophosphazene-derived curing agents

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Chinese Chemical Letters 2022年第8期33卷 4026-4032页

作者： Zhenwei Miao Dongpeng Yan Xiaodong Wang Xinfang Zhang Wenqi zhou Munan Qiu Fan Yang Zhanpeng Wu State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China College of Chemistry Beijing Normal UniversityBeijing 100875China

To obtain high-efficiency flame retardancy of epoxy resins,a cyclophosphazene derivative tri-(ohenylenediamino)cyclotriphosphazene(3 ACP)was successfully synthesized and used as a curing agent for the thermosetting of an epoxy resin *** flame retardant properties,thermal stability,and pyrolysis mechanism of the resultant thermosets were investigated in *** experiments indicated that the synthesized thermoset achieved a UL-94 V-0 rate under a vertical burning test as well as a limiting oxygen index(LOI)of 29.2%,which was able to reach V-0 even when a small amount of 3 ACP was *** electronic microscopic observation demonstrated that the char residue of the thermosets was extremely expanded after the vertical flame *** analysis showed that the samples had a lower initial decomposition temperature when 3 ACP was introduced into the epoxy resin *** indicates that the carbonization ability of the thermosets was significantly improved at elevated *** addition,the incorporation of 3 ACP can effectively suppress the release of combustible gases during the pyrolysis process,and the decomposition of e-44/DDS-3 ACP curing systems also promotes the formation of polyphosphoramides charred layer in the condensed *** investigation on the chemical structures of both the gaseous and condensed phase pyrolysis process confirmed the flame-retardant mechanism of the 3 ACP-cured epoxy ***,the nonflammable halogen-free epoxy resin developed in this study has potential applications in electric and electronic fields for environment protection and human health.

关键词： Cyclotriphosphazene Curing agent epoxy resin Flame retardancy Pyrolysis mechanism

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拉美裔移民与美国国家特性危机

暨南学报（哲学社会科学版） 2006年第3期28卷 9-13页

作者：周聿峨刘虎暨南大学华侨华人研究所暨南大学法学院广东广州510632

近10年来,美国出现了拉美裔移民激增的现象,远远超过美国文化“熔炉”的同化速度。多元文化主义对此问题的处理有着强大的影响力。多元文化主义的正确性不是放之四海而皆准的,在具体的拉美裔移民问题上,忽视移民同化,片面推崇多元文化... 详细信息

近10年来,美国出现了拉美裔移民激增的现象,远远超过美国文化“熔炉”的同化速度。多元文化主义对此问题的处理有着强大的影响力。多元文化主义的正确性不是放之四海而皆准的,在具体的拉美裔移民问题上,忽视移民同化,片面推崇多元文化主义将有可能危及美国文化的核心价值观和美国特性的地位,导致一个分裂的美国社会出现。

关键词：拉美裔移民国际移民多元文化主义同化

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蔬菜农药残留监测问题分析及对策探讨

食品安全导刊 2024年第21期 23-25页

作者：张静王生娥陕西省延安市吴起县农产品质量安全监测站陕西延安717600

蔬菜农药残留问题日益突出,严重威胁着食品安全和消费者健康。本文通过分析当前蔬菜农药残留监测中存在的问题,如检测方法缺乏规范性、样品采集代表性不足、实验室质控体系不健全、数据分析模型有待优化等,提出制定标准化检测流程、优... 详细信息

蔬菜农药残留问题日益突出,严重威胁着食品安全和消费者健康。本文通过分析当前蔬菜农药残留监测中存在的问题,如检测方法缺乏规范性、样品采集代表性不足、实验室质控体系不健全、数据分析模型有待优化等,提出制定标准化检测流程、优化样品采集方案设计、建立实验室质量管理体系、开发先进数据挖掘算法等解决对策,以期为完善蔬菜农药残留监测体系、保障蔬菜质量安全提供参考。

关键词：蔬菜农药残留监测质量控制

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乡村振兴背景下农民主播直播带货中的问题及对策

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新闻传播科学 2024年第2期12卷 323-327页

作者：杜春娥刘灿河北师范大学新闻传播学院河北石家庄

在农产品直播带货已经成为助力乡村振兴重要抓手的背景下,农民作为农产品直播主角,因文化水平有限、直播带货起步较晚等原因,在直播带货中处于弱势地位,他们在粉丝需求洞察、直播素养、数据意识及产品质量方面存在不足。文章在人、货、... 详细信息

在农产品直播带货已经成为助力乡村振兴重要抓手的背景下,农民作为农产品直播主角,因文化水平有限、直播带货起步较晚等原因,在直播带货中处于弱势地位,他们在粉丝需求洞察、直播素养、数据意识及产品质量方面存在不足。文章在人、货、场、文四个维度提出针对性建议,为其提供实践指导。

关键词：直播带货农民主播乡村振兴

Investigation on the Hydro-forming of SUS304 Stainless Steel Dome

维普期刊数据库博看期刊评论

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Chinese Journal of Aeronautics 2006年第B12期19卷 261-264页

作者： XU Yong-chao YUAN Shi-jian CHeN Yu zhou Li-xin KANG Da-chang School of Materials Science and engineering Harbin Institute of Technology Harbin 150001China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The dome hydro-forming was studied theoretically and experimentally. The theoretical analysis shows that the process of dome hydro-forming can be divided into two stages, i.e., firstly forming a hemi-sphere and secondly forming a hemi-toroidal. Theoretically, being larger than those in the outer area of a hemi-toroidal shell, the radial tensile stresses take place in the inner area where fracture is more likely to occur in the forming process. The required hydraulic pressure to form the dome should be determined by the deformation in the outer area, hitting about 12 MPa in theory. The experimental results show that the dome could be produced in one operation by hydro-forming which needs a hydraulic pressure of about 9 MPa. The experimental results prove to agree well with the theoretical analysis. In order to avoid wrinkling and fracture, the closing force acted on the die should be adjusted properly in accordance with the hvdraulic nressure.

关键词： hydro-forming dome SUS304 stainless steel

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医院绩效考核制度建设要素思考

现代医院管理 2024年第4期22卷 109-112页

作者：钟琼娥刘冀武汉市第四医院武汉市430033

如何适应医改新形势,结合医院院情建立起能够推动医院高质量发展的医院内部绩效考核制度,是现代医院运营管理的核心,近几年也成为公立医院落实医改政策的热点方向。本文以S医院的绩效管理探索与实践成效,对公立医院绩效考核制度建设的... 详细信息

如何适应医改新形势,结合医院院情建立起能够推动医院高质量发展的医院内部绩效考核制度,是现代医院运营管理的核心,近几年也成为公立医院落实医改政策的热点方向。本文以S医院的绩效管理探索与实践成效,对公立医院绩效考核制度建设的关键环节和要素进行总结,提出有效的实施路径。

关键词：绩效考核路径要素

Fluoride exposure,Follicle Stimulating Hormone Receptor Gene Polymorphism and Hypothalamus-pituitary-ovarian Axis Hormones in Chinese Women

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Biomedical and environmental Sciences 2015年第9期28卷 696-700页

作者： ZHAO Ming Xu zhou Guo Yu ZHU Jing Yuan GONG Biao HOU Jia Xiang zhou Tong DUAN Li Ju DING Zhong CUI Liu Xin BA Yue Department of environmental Health School of Public HealthZhengzhou University Department of endemic Disease Kaifeng Center for Disease Control and Prevention

The effects of fluoride exposure on thefunctions of reproductive and endocrine systemshave attracted widespread attention in academiccircle nowadays. However, it is unclear whether thegene-environment interaction may modify thesecretion and activity of hypothalamus-pituitary-ovarian （HPO） axis hormones. Thus, the aim of thisstudy was to explore the influence of fluorideexposure and follicle stimulating hormone receptor（FSHR） gene polymorphism on reproductivehormones in Chinese women. A cross sectionalstudy was conducted in seven villages of HenanProvince, China during 2010-2011. A total of 679women aged 18-48 years were recruited throughcluster sampling and divided into three groups, *** fluorosis group （eFG）, defluoridationproject group （DFPG）, and control group （CG） basedon the local fluoride concentration in drinkingwater. The serum levels of gonadotropin releasinghormone （GnRH）, follicle stimulating hormone（FSH）, luteinizing hormone （LH）, and estradiol （e2）were determined respectively and the FSHRpolymorphism was detected by real time PCR *** results provided the preliminary evidenceindicating the gene-environment interaction onHPO axishormones in women.

关键词： FSHR Fluoride exposure,Follicle Stimulating Hormone Receptor Gene Polymorphism and Hypothalamus-pituitary-ovarian Axis Hormones in Chinese Women LH gene

Wnt/β-catenin signaling pathway is active in pancreatic development of rat embryo

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World Journal of Gastroenterology 2006年第16期12卷 2615-2619页

作者： Qi-Ming Wang Ye Zhang Kai-Ming Yang Hong-Ying zhou Hui-Jun Yang Department of Anatomy School of Preclinical and Forensic Medicine Sichuan University Chengdu 610041 China Beida Weixin Biology and Science Company Beijing 100081 China

AIM： To elucidate the role of Wnt/β-catenin signaling pathway in pancreatic development of rat embryo. MeTHODS： The mRNAs of β-catenin, APC, cyclin D1 genes were amplified by means of semiquantitative reverse transcription polymerase chain reaction （RTPCR） from embryonic pancreas in different periods and normal pancreas of rat, respectively. Protein expression of these genes in embryonic pancreas of e14.5-e18.5 was examined by immunohistochemical method. ReSULTS： In embryonic pancreas of e14.5, the transcript amplification of β-catenin and cyclinD1 genes was detected. In embryonic pancreas of e18.5, the transcription levels of β-catenin and cyclinD1 genes became much higher than in other periods. But in adult rat pancreas the transcription of cyclinD1 gene could not be observed. Only until e18.5, the transcript amplification of mRNA of APC gene could be detected. Surprisingly, the transcription level of APC gene became much higher in adult rat pancreas than in embryonic pancreas. By means of immunohistochemical staining, identical results were obtained to the above by RP-PCR, except for β-catenin protein in adult rat pancreas. CONCLUSION： Active Wnt/β-catenin signaling occurs in rat embryonic pancreas and is probably important for pancreatic development and organ formation.

关键词： Wnt/β-catenin signaling Pancreas Development embryo