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电致化学发光传感技术的种类及在食品分析中的研究进展

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食品工业科技 2024年第1期45卷 325-334页

作者：刘树萍邢珂韩博林关桦楠哈尔滨商业大学旅游烹饪学院黑龙江哈尔滨150028 哈尔滨商业大学食品工程学院黑龙江哈尔滨150028

电致化学发光传感技术(Electrochemiluminescence,ECL)是一种结合了电化学和光化学的分析方法,因其可控性强、灵敏度高和响应速度快等优势在食品分析领域引起了广泛关注。ECL是通过改变发射物或共反应物的浓度,使其信号强度发生变化,从... 详细信息

电致化学发光传感技术(Electrochemiluminescence,ECL)是一种结合了电化学和光化学的分析方法,因其可控性强、灵敏度高和响应速度快等优势在食品分析领域引起了广泛关注。ECL是通过改变发射物或共反应物的浓度,使其信号强度发生变化,从而实现对目标物质的灵敏检测。首先,该文总结了经典ECL检测体系及基于新型发射物和共反应物的检测体系,并重点介绍了新型发射物中金属纳米团簇和量子点的最新进展,举例阐述其ECL传感器的结构和检测原理。其次,综述了ECL传感器在食品分析领域中的研究进展。最后对ECL传感技术的未来发展趋势进行了展望,为食品中营养成分和污染物的检测提供参考,同时也促进该技术的进一步研究,助力未来食品检测发展。

关键词：电致化学发光生物传感器食品分析发射物共反应物

Photodegradation mechanism of deltamethrin and fenvalerate

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Journal of Environmental Sciences 2010年第7期22卷 1123-1128页

作者： Pengyan liu Yujie liu Qingxue liu Jinwei liu College of Chemistry and Environmental Sciencel Hebei University Baoding 071002 China Geological & Mineral Central Laboratory of Hebei Province Baoding 071051 China

To understand the degradation and environmental fate of pyrethroids, the process of their photodegradation under simulated natural conditions was investigated. The results showed that the degradation process follows first-order kinetics. The degradation intermediates were identified with gas chromatography-mass spectrometry. A plausible mechanism was discussed to explain the process. Several influences on degradation process were investigated and reported such as the effects of initial concentration of pyrethroids, total time of light irradiation, solvents, and light source, as well as the effect of a few substances that exist in the environment. This study could be a good reference for the degradation of pyrethroids in practical circumstances.

关键词： pyrethroids deltamethrin fenvalerate photodegradation

利用BERT和覆盖率机制改进的HiNT文本检索模型

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智能系统学报 2024年第3期19卷 719-727页

作者：邸剑刘骏华曹锦纲华北电力大学控制与计算机工程学院河北保定071003 复杂能源系统智能计算教育部工程研究中心河北保定071003

为有效提升文本语义检索的准确度,本文针对当前文本检索模型衡量查询和文档的相关性时不能很好地解决文本歧义和一词多义等问题,提出一种基于改进的分层神经匹配模型(hierarchical neural matching model,HiNT)。该模型先对文档的各个... 详细信息

为有效提升文本语义检索的准确度,本文针对当前文本检索模型衡量查询和文档的相关性时不能很好地解决文本歧义和一词多义等问题,提出一种基于改进的分层神经匹配模型(hierarchical neural matching model,HiNT)。该模型先对文档的各个段提取关键主题词,然后用基于变换器的双向编码器(bidirectional encoder representations from transformers,BERT)模型将其编码为多个稠密的语义向量,再利用引入覆盖率机制的局部匹配层进行处理,使模型可以根据文档的局部段级别粒度和全局文档级别粒度进行相关性计算,提高检索的准确率。本文提出的模型在MS MARCO和webtext2019zh数据集上与多个检索模型进行对比,取得了最优结果,验证了本文提出模型的有效性。

关键词：基于变换器的双向编码器分层神经匹配模型覆盖率机制文本检索语义表示特征提取自然语言处理相似度多粒度

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人工气道规范化护理适宜技术对急诊监护室机械通气患者相关并发症、舒适度及预后的影响

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中国基层医药 2024年第9期31卷 1424-1428页

作者：叶新红叶健晓刘芳丽水市中心医院急诊监护室丽水323000 丽水市中心医院急诊医学科丽水323000

目的探究人工气道规范化护理适宜技术对急诊监护室机械通气患者相关并发症、舒适度及预后的影响。方法前瞻性收集2018年1月到2023年10月丽水市中心医院急诊监护室收治的机械通气患者769例为研究对象,按照随机数字表法分为对照组(384例)... 详细信息

目的探究人工气道规范化护理适宜技术对急诊监护室机械通气患者相关并发症、舒适度及预后的影响。方法前瞻性收集2018年1月到2023年10月丽水市中心医院急诊监护室收治的机械通气患者769例为研究对象,按照随机数字表法分为对照组(384例)及观察组(385例),对照组采用常规护理干预,观察组则同时进行人工气道规范化护理适宜技术干预。比较两组机械通气时间、急诊监护室住院时间、总住院时间、干预前后动脉血气、舒适度、预后及并发症发生率。结果观察组机械通气时间[(4.61±0.52)d比(6.95±0.81)d]、急诊监护室住院时间[(5.12±0.63)d比(6.95±0.81)d]、总住院时间[(12.31±1.45)d比(7.11±0.76)d]均短于对照组(t=47.68、39.53、30.18,均P<0.05);干预后,两组动脉血氧分压(PaO_(2))、动脉血氧饱和度(SaO_(2))较干预前均明显增高,且观察组均高于对照组(t=12.73、16.62,均P<0.05),两组二氧化碳分压(PaCO_(2))、数字评分量表(NRS)评分、急性生理与慢性健康评分Ⅱ(APACHEⅡ)评分较干预前均明显降低,且观察组均低于对照组(t=128.96、68.26、44.40,均P<0.05)。干预后观察组并发症总发生率低于对照组,差异有统计学意义(χ ^(2)=15.21,P<0.05)。结论人工气道规范化护理适宜技术应用于急诊监护室机械通气患者中,可明显缩短患者康复进程,改善氧合状态、预后及提高舒适度,有效减少呼吸机相关性并发症的发生。

关键词：气道管理护理急诊室,医院呼吸,人工患者舒适度预后

A New Method for Locating Calculation of Arbitrary Spatial Straight Line or Plane in NC Machining

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厦门大学学报（自然科学版） 2002年第S1期41卷 149-150页

作者： YAN Shu-tian, liu Tao, WU Zai-xin, HU Chi-bing, HU Li-zh i (College of Mechano-Electronic Engineering, Gansu University of Techn ology, Lanzhou 730050, China)

In the manufacturing process, we often encounter so me location machining of space arbitrary straight lines and planes that are not on ly unparalleled but also not vertical with the machine tool spindle or the cutti ng tool. In the past, we can do the location machining through the methods of dr awing line and making level in the ordinary machine tool. In the numerical contr ol machining of the CNC machine tool and manufacturing center, however, the spac e location and angle of the arbitrary straight lines and planes must be precisel y calculated in advance. So that precisely locating can be guaranteed in machini ng. Therefore, how to work out the space location angle of the arbitrary straigh t lines and planes to be machined both conveniently and precisely, turns out to be the must-be-solved chief problem in the numerical control machining. In thi s paper, through the deeply research of this problem, a new kind of calculating formula that calculates and defines the space location angle of the arbitrary st raight lines and planes by using the methods of analytic calculating. The formul a has been applied in the practical manufacturing calculation. It is proved that the new space angle calculating methods of arbitrary straight lines and planes is convenient in calculating and precise in locating. And it provides us a n ew, brief and precise calculating method in the numerical control machining of t he numerical control machine tool and manufacturing center.

关键词： arbitrary straight line arbitrary plane pr ojected angle inclination location

西藏墨脱复杂地形X波段相控阵偏振天气雷达降水观测和反演方法研究

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高原气象 2024年第1期43卷 99-113页

作者：陈浩然耿飞刘黎平杨华中国气象科学研究院灾害天气国家重点实验室北京100081

墨脱的降水变化与印度洋、孟加拉湾的水汽向内陆的输送、夏季风及我国东部雨带的推进过程联系紧密。它的独特地形与西南气流的相互作用在当地形成了年均降水超过2000 mm的降水带。但墨脱的复杂地形与有限的电力交通条件造成了降水观测... 详细信息

墨脱的降水变化与印度洋、孟加拉湾的水汽向内陆的输送、夏季风及我国东部雨带的推进过程联系紧密。它的独特地形与西南气流的相互作用在当地形成了年均降水超过2000 mm的降水带。但墨脱的复杂地形与有限的电力交通条件造成了降水观测的困难。2019年,第二次青藏高原综合科学考察研究任务专题项目在墨脱设置了一部X波段双偏振相控阵雷达,实现了对墨脱云降水的连续观测,对当地生态环境和云水资源研究以及高原东南水汽通道特征研究等具有重要的意义。文中使用墨脱X波段双偏振相控阵雷达2020年6-8月的观测数据,使用统计手段筛选降水回波片段,整合后构造得到符合墨脱复杂地形的混合仰角;利用2019年墨脱雨滴谱数据计算雷达参量、拟合得到适合墨脱地区降水特点的X波段天气雷达定量降水估测(QPE)公式。在此基础上选取2020年7-8月三次累积降水量、平均雨强、持续时间各不相同的降水过程,使用线性规划方案计算ΦDP(差分传播相移)、最小二乘拟合计算KDP(差分传播相移率)、“ZPHI”降水廓线算法订正zh(反射率因子);以zh和KDP为阈值,使用R(zh)与R(KDP)分段估测降水,与单独使用R(zh)和R(KDP)的估测结果进行对比;并基于降水估测结果和雷达参量的水平分布探讨降水分布与地形的关系。本文经过质量控制的zh、 KDP数据质量有明显改善;使用统计方法构造的混合仰角有效回波面积大于使用SRTM1 v3.0地形数据构造的混合仰角,三次降水的典型时刻参量与过程累积降水量和平均zh、 ZDR能初步反映降水变化与地形的关系;本文的降水估测公式和分段估测降水方法整体结果表现良好,各评估参数均具有较好的表现;结果表明:(1)墨脱雷达周边地形变化剧烈,根据现有地形数据构造的混合仰角在降水估测中表现不如本文统计筛选雷达观测数据得到的混合仰角数据;(2)本文采用的数据质控方法、定量降水估测公式与分段估测方法(PEM)在降水反演中表现良好,与单一的R(zh)、 R(KDP)方法相比,得到的结果在CC和RMSE无明显变化的情况下,估测误差明显减小;(3)墨脱降水的发生发展或与西南气流被河谷偏北方山坡抬升有关,较大雨强、较小粒子直径的云位于地势平缓的谷底。

关键词： X波段相控阵偏振雷达线性规划雷达混合仰角定量降水估测

Accurate prediction of myopic progression and high myopia by machine learning

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Precision Clinical Medicine 2024年第1期7卷 14-20页

作者： Jiahui Li Simiao Zeng zhihuan Li Jie Xu zhuo Sun Jing zhao Meiyan Li Zixing Zou Taihua Guan Jin Zeng zhuang liu Wenchao Xiao Ran Wei Hanpei Miao Ian Ziyar Junxiong Huang Yuanxu Gao Yangfa Zeng Xing-Tao zhou Kang zhang Guangzhou Women and Children's Medical Center Guangzhou Medical UniversityGuangzhou 510120China Guangzhou National Laboratory Guangzhou 510o0oChina zhuhai International Eye Center of the First Affiliated Hospital of Faculty of Medicine Macao University of Science and TechnologyZhuhai 519000China Beijing Institute of Ophthalmology Beijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing 100069China Key Laboratory of Myopia Ministry of HealthShanghai Key Laboratory of Visual Impairment and RestorationDepartment of OphthalmologyEye InstituteEye and EarNoseand Throat HospitalFudan UniversityShanghai 200031China DongguanPeople's Hospital The First School of Clinical MedicinelSouthern Medical UniversityDongguan 523059China State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangzhou 510060China Wenzhou Eye Hospital and Institute for Advanced Study on Eye Health and Diseases Wenzhou Medical UniversityWenzhou 32500oChina

Background Myopia is a leading cause of visual impairment in Asia and ***,accurately predicting the progression of myopia and the high risk of myopia remains a *** study aims to develop a predictive model for the development of *** We first retrospectively gathered 612530 medical records from five independent cohorts,encompassing 227543 patients ranging from infants to young ***,we developed a multivariate linear regression algorithm model to predict the progression of myopia and the risk of high *** The model to predict the progression of myopia achieved an R^(2) value of 0.964 vs a mean absolute error(MAE)of 0.119D[95%confidence interval(CI):0.119,1.146]in the internal validation *** demonstrated strong generalizability,maintaining consistent performance across external validation sets:R^(2)=0.950 vs MAE=0.119D(95%CI:0.119,1.136)in validation study 1,R^(2)=0.950 vs MAE=0.121D(95%CI:0.121,1.144)in validation study 2,and R^(2)=0.806 vs MAE=−0.066D(95%CI:−0.066,0.569)in the Shanghai Children Myopia *** the Beijing Children Eye Study,the model achieved an R^(2) of 0.749 vs a MAE of 0.178D(95%CI:0.178,1.557).The model to predict the risk of high myopia achieved an area under the curve(AUC)of 0.99 in the internal validation set and consistently high area under the curve values of 0.99,0.99,0.96 and 0.99 in the respective external validation *** Our study demonstrates accurate prediction of myopia progression and risk of high myopia providing valuable insights for tailoring strategies to personalize and optimize the clinical management of myopia in children.

关键词： myopia progression machine learning prevention precision medicine

大豆分离蛋白与茶多酚稳定的高内相Pickering乳液替代脂肪对肉丸品质的影响

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食品工业科技 2024年第6期45卷 59-66页

作者：刘树萍彭秀文张佳美李沛钊哈尔滨商业大学旅游烹饪学院黑龙江哈尔滨150028

为降低饱和脂肪摄入过高对人体健康造成的危害,本实验选择大豆分离蛋白与大豆油为原料制备高内相Pickering乳液(High interphase Pickering emulsions,HIPEs),并以茶多酚作为活性物质进一步优化乳液性能,以替代肉丸中动物脂肪。分别选... 详细信息

为降低饱和脂肪摄入过高对人体健康造成的危害,本实验选择大豆分离蛋白与大豆油为原料制备高内相Pickering乳液(High interphase Pickering emulsions,HIPEs),并以茶多酚作为活性物质进一步优化乳液性能,以替代肉丸中动物脂肪。分别选用水、HIPEs及负载茶多酚的HIPEs替代猪背脂肪,制备了6种不同的配方,并对肉丸的理化、感官指标进行表征。结果表明,相较于对照组,除pH外各指标均存在显著性差异(P<0.05),随着乳液的添加,肉丸的蒸煮得率可提高至93.59%,水分含量上升至66.91%,脂肪含量下降至8.42%,蛋白质含量上升至14.48%,肉丸的硬度、弹性、内聚性、咀嚼性均随着乳液的添加而上升,pH无明显差异,添加Pickering乳液后肉丸的L值提高,a、b值因茶多酚的添加而升高,含茶多酚的HIPEs对肉丸水分与脂肪渗出率的改善最佳,分别降低至1.57%与0.019%,硫代巴比妥酸(Thiobarbituric acid,TBA)值最低为4.12 mg/kg,添加乳液后,感官评价较对照组均有所上升。以HIPEs作为脂肪替代可有效减少肉丸中脂肪含量,提高肉丸的出品率及品质,本研究可为减脂肉制品的开发提供一定参考。

关键词：高内相 Pickering 乳液茶多酚脂肪替代肉丸脂肪氧化

Exact Solutions for Piezoelectric Materials with an Elliptic Hole or a Crack under Uniform Internal Pressure

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Chinese Journal of Mechanical Engineering 2012年第4期25卷 845-852页

作者： liu Shuhong SHEN Yingming liu Jinxi Department of Engineering Mechanics Shijiazhuang Tiedao University Shijiazhuang 050043 China Department of Science and Technology Shijiazhuang Tiedao University Shijiazhuang 050043 China

The existing investigations on piezoelectric materials containing an elliptic hole or a crack mainly focus on remote uniform tensile *** order to have a better understanding for the fracture behavior of piezoelectric materials under different loading conditions,theoretical and numerical solutions are presented for an elliptic hole or a crack in transversely isotropic piezoelectric materials subjected to uniform internal pressure and remote electro-mechanical *** the basis of the complex variable approach,analytical solutions of the elastic and electric fields inside and outside the defect are derived by satisfying permeable electric boundary condition at the surface of the elliptical *** an example of PZT-4 ceramics,numerical results of electro-elastic fields inside and outside the crack under various electric boundary conditions and electro-mechanical loads are given,and graphs of the electro-elastic fields in the vicinity of the crack tip are *** non-singular term is compared to the asymptotic one in the *** is shown that the dielectric constant of the air in the crack has no effect on the electric displacement component perpendicular to the crack,and the stresses in the piezoelectric material depend on the material properties and the mechanical loads on the crack surface and at infinity,but not on the electric loads at *** figures obtained are strikingly similar to the available *** the existing work,the existence of electric fields inside an elliptic hole or a crack is considered,and the piezoelectric solid is subjected to complicated electro-mechanical loads.

关键词： piezoelectric material elliptic hole crack boundary condition electro-elastic fields