检索结果-南通市图书馆

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气液缓冲技术在管排定位装置上的应用

轧钢 2016年第5期33卷 91-92页

作者：于龙程云艳郑召丰北京金自天和缓冲技术有限公司北京100071

管排定位装置的精度直接影响到成品钢管的剪切精度及切损率,本文将气液缓冲技术运用到管排定位装置上,并给出力学性能分析及热交换分析,该装置的应用提高了钢管的成材率。

关键词：管排定位气液缓冲器定位装置

某地市售蔬菜重金属污染状况及其健康风险分析

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中国卫生产业 2018年第21期15卷 150-152页

作者：刘雪芳闫兆凤荣成市食品药品食品药品稽查大队山东荣成264300 威海市疾病预防控制中心山东威海264200

目的了解某地售蔬菜中重金属污染状况,评价其食用健康风险。方法在流通环节采集9类367份蔬菜样品,依据国家标准,测定铅、镉、及总砷含量,采用单因子污染指数和综合污染指数评价蔬菜中金属污染水平,采用目标危害系数,评价人群食用健康风... 详细信息

目的了解某地售蔬菜中重金属污染状况,评价其食用健康风险。方法在流通环节采集9类367份蔬菜样品,依据国家标准,测定铅、镉、及总砷含量,采用单因子污染指数和综合污染指数评价蔬菜中金属污染水平,采用目标危害系数,评价人群食用健康风险。结果 9类蔬菜样品中,铅平均含量最高,铅、镉及总砷检出率分别为42.23%、71.12%和11.44%;铅和总砷超标率分别为0.82%和0.54%;叶菜类铅、镉以及鲜豆类总砷含量相对较高;水生类总砷达到尚清洁水平,处于警戒线,其他8类蔬菜的单因子污染指数和综合污染指数均<1,蔬菜为清洁状态,处于安全水平;不同蔬菜单一金属THQ值和TTHQ值均<1,说明通过摄入单一类别蔬菜的铅、镉及总砷对人群无明显的健康风险。结论该地蔬菜样品中铅含量相对较高,各类蔬菜对人群健康风险不大。

关键词：蔬菜污染重金属健康风险

数字时代“听书”视阈下图书馆阅读推广服务研究

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四川图书馆学报 2018年第4期 57-60页

作者：魏海燕姚照丰长沙市图书馆长沙410005

"互联网+"时代和移动智能终端为有声读物发展带来新机遇,"听书"已成为大众阅读的重要选择方式,为以视觉阅读服务为主要内容的图书馆带来新的发展空间。选取样本图书馆的有声阅读推广活动进行分析,提出图书馆应从建立"听书"保障政策体系... 详细信息

"互联网+"时代和移动智能终端为有声读物发展带来新机遇,"听书"已成为大众阅读的重要选择方式,为以视觉阅读服务为主要内容的图书馆带来新的发展空间。选取样本图书馆的有声阅读推广活动进行分析,提出图书馆应从建立"听书"保障政策体系、加强音频资源建设、搭建媒介新平台、创新"听书"推广模式等方面着手,扩大图书馆阅读推广服务的空间维度,助推全民阅读事业新发展。

关键词：听书有声阅读音频资源阅读推广

并联间隙在云南高海拔地区配电线路的应用方法

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电力学报 2015年第4期30卷 310-313页

作者：龚石林冯彦钊杨鑫云南电网公司生产设备部昆明650011 长沙理工大学电气与信息工程学院长沙410114

在绝缘子串旁加装并联的保护间隙是"疏导式"防雷保护的典型措施,而在高海拔地区绝缘子串与并联间隙的雷电冲击绝缘配合需要重新试验。在昆明地区进行了负极性标准雷电冲击电压下PS15/500支柱式绝缘子及其并联的可调式保护间隙的雷电冲... 详细信息

在绝缘子串旁加装并联的保护间隙是"疏导式"防雷保护的典型措施,而在高海拔地区绝缘子串与并联间隙的雷电冲击绝缘配合需要重新试验。在昆明地区进行了负极性标准雷电冲击电压下PS15/500支柱式绝缘子及其并联的可调式保护间隙的雷电冲击特性试验,采用正态概率分布的方法得到了对应击穿概率的放电电压,从击穿概率的角度进行了绝缘配合设计,得到了并联间隙最佳的绝缘配合间距,为并联间隙在高海拔地区的应用提供了数据参考和方法基础。

关键词：并联间隙高海拔地区配电线路正态分布

2008～2010年威海市农村生活饮用水集中供水水质监测分析

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现代预防医学 2012年第7期39卷 1622-1623页

作者：李作宁籍继颖姜兆刚闫兆风丁美珠威海市疾病预防控制中心

目的了解威海市农村生活饮用水集中供水水质卫生状况,为今后农村饮用水管理提供基础资料。方法对威海市所辖3市1区部分集中供水的农村2008～2010年的生活饮用水的水质采样检测结果进行统计分析。结果各年度间水质检测平均合格率无显著差... 详细信息

目的了解威海市农村生活饮用水集中供水水质卫生状况,为今后农村饮用水管理提供基础资料。方法对威海市所辖3市1区部分集中供水的农村2008～2010年的生活饮用水的水质采样检测结果进行统计分析。结果各年度间水质检测平均合格率无显著差异;900份生活饮用水中合格248份,平均合格率27.56%;不合格指标主要是微生物;各年度感官性状及一般化学指标平均合格率相比有显著差异,各年度毒理指标平均合格率相比有显著差异;枯水期的感官性状和一般化学指标合格率以及微生物指标合格率均明显高于丰水期。结论应加强威海市农村集中供水卫生管理工作,确保农村居民饮用水安全。

关键词：农村生活饮用水集中供水监测

Nanocarrier-mediated siRNA delivery:a new approach for the treatment of traumatic brain injury-related Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2538-2555页

作者： Jie Jin Huajing Zhang Qianying Lu Linqiang Tian Sanqiao Yao feng Lai yangfan Liang Chuanchuan Liu Yujia Lu Sijia Tian yanmei zhao Wenjie Ren Institute of Disaster and Emergency Medicine Tianjin UniversityTianjinChina Key Laboratory for Disaster Medicine Technology TianjinChina Henan Medical Key Laboratory for Research of Trauma and Orthopedics The Third Affiliated Hospital of Xinxiang Medical UniversityXinxiangHenan ProvinceChina Clinical Medical Center of Tissue Engineering and Regeneration Xinxiang Medical UniversityXinxiangHenan ProvinceChina Institutes of Health Central Plain Xinxiang Medical UniversityXinxiangHenan ProvinceChina School of Public Health Xinxiang Medical UniversityXinxiangHenan ProvinceChina

Traumatic brain injury and Alzheimer's disease share pathological similarities,including neuronal loss,amyloid-βdeposition,tau hyperphosphorylation,blood-brain barrier dysfunction,neuroinflammation,and cognitive ***,traumatic brain injury can exacerbate Alzheimer's disease-like pathologies,potentially leading to the development of Alzheimer's *** offer a potential solution by facilitating the delive ry of small interfering RNAs across the blood-brain barrier for the targeted silencing of key pathological genes implicated in traumatic brain injury and Alzheimer's disease.U nlike traditional approaches to neuro regeneration,this is a molecula r-targeted strategy,thus avoiding non-specific drug *** review focuses on the use of nanocarrier systems for the efficient and precise delive ry of siRNAs,discussing the advantages,challenges,and future *** principle,siRNAs have the potential to target all genes and non-targetable protein s,holding significant promise for treating various *** the various therapeutic approaches currently available for neurological diseases,siRNA gene silencing can precisely"turn off"the expression of any gene at the genetic level,thus radically inhibiting disease progression;however,a significant challenge lies in delivering siRNAs across the blood-brain *** have received increasing attention as an innovative drug delive ry tool fo r the treatment of brain *** are considered a potential therapeutic strategy with the advantages of being able to cross the blood-brain barrier,targeted drug delivery,enhanced drug stability,and multifunctional *** use of nanoparticles to deliver specific modified siRNAs to the injured brain is gradually being recognized as a feasible and effective *** this strategy is still in the preclinical exploration stage,it is expected to achieve clinical translation in the future,creating a new field of molecular tar

关键词： blood-brain barrier cognitive dysfunction exosomes gene silencing immunotherapy inorganic nanomaterials liposome nanoparticles neuroinflammation polymer nanoparticles stem cells

Modular assembly of Co4-thiacalix[4]arene units and Keggin-type SiW12O40 for visible-light photothermal conversion

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Tungsten 2025年第1期 112-119页

作者： Jia-Hui Li Qing zhao Dong-Ao Mao Kun Zhou Bao-Kuan Chen yan-feng Bi School of Petrochemical Engineering Liaoning Petrochemical University

The construction of metal-organic coordination clusters（MCCs） using modular secondary building units is an important method for preparing functional *** this study,two new MCCs modularly assembled from Keggin-type {SiW12O40}H4TC4A=p-tert-Butylthiacalix[4]arene(SiW12) units and thiacalixarene-supported Co4-thiacalix[4]arene(Co4-TC4A polynuclear second-building units（PSBUs,H4TC4A=p-tert-Butylthiacalix[4]arene） are *** two MCCs,abbreviated as Co4-SiW12and Co8-SiW12,were structurally characterized by single-crystal X-ray *** Co4-SiW12is a supramolecular structure involving cation-anion interactions between Co4-TC4A PSBUs and ***8-SiW12features "barbell-like" shapes with two Co4-TC4A coordinatively linked to a Keggin-type SiW12unit on opposite via W-O_t-Co *** coordination of Co4-TC4A to SiW12in Co8-SiW12resulted in significantly improved photothermal conversion performances compared with Co4-SiW12and pure SiW12or ***-gap determination and photophysical analysis combined with density functional theory calculations indicated the binding mode between Co4-TC4A PSBUs and SiW12,which considerably influences the way of electron transport and the conversion ability of visible light to heat.

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Biome reconstruction on the Tibetan Plateau since the Last Glacial Maximum using a machine learning method

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Science China Earth Sciences 2022年第3期65卷 518-535页

作者： feng QIN yan zhao Xianyong CAO Key Laboratory ofLand Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Alpine Paleoecology and Human Adaptation(ALPHA)Group State Key Laboratory of Tibetan Plateau Earth System Science(LATPES)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Historical biome changes on the Tibetan Plateau provide important information that improves our understanding of the alpine vegetation responses to climate ***,a comprehensively quantitative reconstruction of the historical Tibetan Plateau biomes is not possible due to the lack of quantitative methods that enable appropriate classification of alpine biomes based on proxy data such as fossil pollen *** this study,a pollen-based biome classification model was developed by applying a random forest algorithm(a supervised machine learning method)based on modern pollen assemblages on and around the Tibetan Plateau,and its robustness was assessed by comparing its results with the predictions of the biomisation *** results indicated that modern biome distributions reconstructed using the random forest model based on modern pollen data generally concurred with the observed zonal *** random forest model had a significantly higher accuracy than the biomisation method,indicating the former is a more suitable tool for reconstructing alpine biome changes on the Tibetan *** random forest model was then applied to reconstruct the Tibetan Plateau biome changes from 22 ka BP to the present based on 51 fossil pollen *** reconstructed biome distribution changes on the Tibetan Plateau generally corresponded to global climate changes and Asian monsoon *** the Last Glacial Maximum,the Tibetan Plateau was mainly desert with subtropical forests distributed in the *** the last deglaciation,the alpine steppe began expanding and gradually became zonal vegetation in the central and eastern *** meadow occupied the eastern and southeastern areas of the Tibetan Plateau since the early Holocene,and the forest-meadow-steppe-desert pattern running southeast to northwest on the Tibetan Plateau was established *** the mid-Holocene,subtropical forests extended north,which reflected the“optimum”***

关键词： Biome reconstruction Random forest algorithm Biomisation method Pollen data Last Glacial Maximum Tibetan Plateau

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Bending Stiffness of Concrete-Filled Steel Tube and Its Influence on Concrete Placement Timing of Composite Beam-String Structure

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Structural Durability & Health Monitoring 2025年第1期19卷 55-75页

作者： Zhenyu Zhang Quan Jin Haitao Zhang zhao Liu Yuyang Wu Longfei Zhang Renzhang yan CCCC Third Highway Engineering Co. Ltd.Beijing101300China School of Civil Engineering Chongqing Jiaotong UniversityChongqing400074China

When the upper chord beam of the beam-string structure(BSS)is made of concrete-filled steel tube(CFST),its overall stiffness will change greatly with the construction of concrete placement,which will have an impact on the design of the tensioning plans and selection of control measures for the *** order to accurately obtain the bending stiffness of CFST beam and clarify its impact on the mechanical properties of composite BSS during construction,the influence of some factors such as height-width ratio,wall thickness of steel tube,elasticity modulus of concrete,and friction coefficient on the bending stiffness are analyzed parametrically by the numerical simulation technology based on an actual *** calculation formula of the equivalent bending stiffness of CFST is also established through mathematical statistical ***,the equivalent bending stiffness is introduced into the construction and use stages of the composite BSS,respectively,and the mechanical properties such as prestress-tensioning control value,structural deformation,and internal force of key members are comparatively analyzed when adopting two different construction ***,the optimal construction plan of concrete placement first and then prestress-tensioning is proposed.

关键词： Concrete panels freeze-thaw damage compression-shear crack tension-shear crack