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封闭隔离环境暴露对海员脑功能影响的静息态fMRI研究

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分子影像学杂志 2024年第3期47卷 264-270页

作者：褚者者张建平蔡知远陈双红海军军医大学海军特色医学中心上海200433 上海体育大学运动健康学院上海200438 复旦大学化学系上海200433

目的探讨海上封闭隔离环境及暴露年限对海员脑功能活动的影响,为预防职业环境暴露对海员脑功能损伤提供依据。方法于2023年8月招募30名长期从事海上作业的男性职业海员作为海员组,年龄19~29岁,工作年限1~11年,在三亚市人民医院采用Magne... 详细信息

目的探讨海上封闭隔离环境及暴露年限对海员脑功能活动的影响,为预防职业环境暴露对海员脑功能损伤提供依据。方法于2023年8月招募30名长期从事海上作业的男性职业海员作为海员组,年龄19~29岁,工作年限1~11年,在三亚市人民医院采用Magneton Skyra 3.0 T磁共振扫描仪进行静息态脑功能磁共振成像;匹配无海上作业经历的普通被试30名作为对照组,年龄18~28岁,Magneton Skyra 3.0 T静息态磁共振数据从OpenNeuro公共数据库下载。计算两组静息态ALFF、fALFF和ReHo指标,采用双样本t检验比较两组间脑区ALFF、fALFF和ReHo的差异,进一步采用偏相关分析法分析ALFF、fALFF和ReHo值与海员工作年限和出海年限的相关性。结果与对照组相比,海员组右侧中央后回和右侧小脑脚1区的ALFF值较高,左侧嗅皮质的ALFF值较低;左内侧和旁扣带脑回以及右颞级颞上回的fALFF值较高,右侧枕中回、左侧顶下缘角回、左侧中央前回和右侧中央前回的fALFF值较低;右侧海马旁回ReHo值增高,右侧颞下回、右侧眶部额中回、左侧顶下缘角回、左侧角回、右侧颞中回和左侧颞中回ReHo值降低,差异有统计学意义(P<0.05),采用GRF校正,体素水平P<0.001,团块水平P<0.05。海员组右侧中央后回ALFF值与海员工作年限呈弱正相关(r=0.369,P=0.049),右侧枕中回f ALFF值与海员工作年限呈弱负相关(r=-0.370,P=0.048)。结论长期职业封闭隔离环境暴露对海员多个脑区的脑功能活动造成影响,海员右侧中央后回的ALFF值与工作年限存在弱正相关性,右侧枕中回的fALFF值与海员的工作年限呈弱负相关。

关键词：封闭隔离环境静息态功能磁共振脑功能海员

Achievable hole concentration at room temperature as a function of Mg concentration for MOCVD-grown p-GaN after sufficient annealing

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Journal of Semiconductors 2024年第8期45卷 67-73页

作者： Siyi Huang Masao Ikeda Feng zhang Minglong zhang Jianjun Zhu Shuming zhang jianping Liu School of Nano-Tech and Nano-Bionics University of Science and Technology of ChinaHefei 230026China Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of SciencesSuzhou 215123China Key Laboratory of Nanodevices and Applications Chinese Academy of SciencesSuzhou 215123China

Relationship between the hole concentration at room temperature and the Mg doping concentration in p-GaN grown by MOCVD after sufficient annealing was studied in this *** annealing conditions were applied to obtain sufficient activation for p-GaN samples with different Mg doping *** concentration,resistivity and mobility were characterized by room-temperature Hall *** Mg doping concentration and the residual impurities such as H,C,O and Si were measured by secondary ion mass spectroscopy,confirming negligible compensations by the *** hole concentration,resistivity and mobility data are presented as a function of Mg concentration,and are compared with literature *** appropriate curve relating the Mg doping concentration to the hole concentration is derived using a charge neutrality equation and the ionized-acceptor-density[N-(A)^(-)](cm^(−3))dependent ionization energy of Mg acceptor was determined asE_(A)^(Mg)=184−2.66×10^(−5)×[N_(A)^(-)]1/3 meV.

关键词： p-GaN hole concentration electrical properties annealing ionization energy

应用型本科院校“食品分析与检测综合训练”课程教学改革

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农产品加工 2024年第13期 120-122,125页

作者：巫永华陈尚龙张文莉师聪张建萍刘恩岐徐州工程学院江苏省食品与生物工程实验中心江苏徐州221018

“食品分析与检测综合训练”是食品质量与安全专业学生重要的实践课程,要求学生在全面掌握食品样品的采样、前处理、分析等步骤,以及食品中营养、危害成分和添加剂的检测原理和方法的基础上,科学选用合适的分析检测仪器对样品进行检测,... 详细信息

“食品分析与检测综合训练”是食品质量与安全专业学生重要的实践课程,要求学生在全面掌握食品样品的采样、前处理、分析等步骤,以及食品中营养、危害成分和添加剂的检测原理和方法的基础上,科学选用合适的分析检测仪器对样品进行检测,正确记录及处理数据并进行科学分析讨论,规范撰写报告,掌握质量控制手段。针对传统食品分析与检测实验存在的问题,探讨并实践了“食品分析与检测综合训练”的教学改革,有力提高了学生文献综述、实验设计、正确操作、数据处理、综合分析和科学思维的能力,并培养了学生的专业素养和工匠精神。

关键词：食品分析与检测综合训练食品质量与安全教学改革

China's Economic Development and its Impact on the World during the Past 40-year Reform and Opening-up

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Peace 2018年第2期 8-13页

作者： zhang jianping Western Asian and African Studies the Research Institute of the Ministry of Commerce Shen Bo Economics College Peking University

The year 2018 coincides with the 40 th anniversary of China's reform and opening-up. Over the past 40 years, China's economic development has made great achievements, which may be regarded as a "miracle" of economic development. This economic miracle is reflected in the scale and quality of China's economic development. China's 4-decade economic development has not only brought great changes to Chinese society, but also has a profound impact on the growth and development of the world economy. However, this does not mean that China has found a complete new road to economic development. China needs to correctly view its achievements in the 40-year reform and opening-up, and accelerate the transformation and upgrading of economic development in a new era, so as to make a greater contribution to the sustainable development of the world economy.

关键词： China’s Economic Development and its Impact on the World during the Past 40-year Reform and Opening-up World

Tribological Behaviors of Electroless Nickel-Boron Coating on Titanium Alloy Surface

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 309-320页

作者： Yao Jia jianping Lai Jiaxin Yu Huimin Qi Yafeng zhang Hongtu He Key Laboratory of Testing Technology for Manufacturing Process in Ministry of Education State Key Laboratory of Environment-Friendly Energy MaterialsSouthwest University of Science and TechnologyMianyang 621010China

Titanium alloys are excellent structural materials in engineering fields,but their poor tribological properties limit their further *** plating is an effective method to enhance the tribological performance of alloys,but it is difficult to efficiently apply to titanium alloys,due to titanium alloy’s strong chemical *** this work,the electroless Nickel-Boron(Ni-B)coating was successfully deposited on the surface of titanium alloy(Ti-6AL-4V)via a new pre-treatment ***,linearly reciprocating sliding wear tests were performed to evaluate the tribological behaviors of titanium alloy and its electroless Ni-B *** was found that the Ni-B coatings can decrease the wear rate of the titanium alloy from 19.89×10^(−3)mm^(3)to 0.41×10^(−3)mm^(3),which attributes to the much higher hardness of Ni-B *** heat treatment,the hardness of Ni-B coating further increases corresponding to coating crystallization and hard phase ***,heat treatment does not improve the tribological performance of Ni-B coating,due to the fact that higher brittleness and more severe oxidative wear exacerbate the damage of heat-treated ***,the Ni-B coatings heat-treated both in air and nitrogen almost present the same tribological *** finding of this work on electroless coating would further extend the practical applications of titanium alloys in the engineering fields.

关键词： Electroless coating Titanium alloy Tribology Wear Heat treatment Nanoindentation

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胡麻17份亲本及组合主要性状的配合力分析

分子植物育种 2024年第10期22卷 3312-3323页

作者：党照张建平王利民汪平齐燕妮李闻娟谢亚萍赵玮甘肃省农业科学院作物研究所兰州730070

为了筛选胡麻优质品系作为杂交亲本配置组合,以求进一步在胡麻产量和品质方面有所突破,以本单位新培育的8个胡麻品系作为母本,与9个成熟品种进行组配,共配制72个杂交组合,旨在测定亲本的一般配合力(GCA)和特殊配合力(SCA)。结果表明,CP2... 详细信息

为了筛选胡麻优质品系作为杂交亲本配置组合,以求进一步在胡麻产量和品质方面有所突破,以本单位新培育的8个胡麻品系作为母本,与9个成熟品种进行组配,共配制72个杂交组合,旨在测定亲本的一般配合力(GCA)和特殊配合力(SCA)。结果表明,CP2205在和产量密切相关的单株果数方面GCA表现突出,在千粒重和每果粒数方面也有正向表现;品质方面,CP2205在含油率、亚油酸、亚麻酸等重要方面GCA均表现较好,可作为重点品系进行组配。配置组合时可选用每果粒数、蛋白质和木酚素GCA值较高的品种来进行组配,从而提升后代材料的产量和品质。09-3-11在亚麻酸和亚油酸方面具有较高GCA效应,但在单株果数和每果粒数方面效应较低,组配时应选择这两方面GCA表现较为突出的品种作为亲本,可更容易选出优良后代。

关键词：胡麻一般配合力特殊配合力杂种优势

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基因型与环境对胡麻产量和脂肪酸的影响

分子植物育种 2024年第3期22卷 881-891页

作者：党照王利民齐燕妮李闻娟汪平谢亚萍赵玮张建平甘肃省农业科学院作物研究所兰州730070

为了对胡麻新品种(系)的丰产性、稳定性、适应性以及各试验点的辨别力进行客观评价,本研究以参加2009—2010年甘肃省胡麻区域试验的品种为材料,通过AMMI模型对其产量和脂肪酸含量进行分析。结果表明,不同的年份和环境对产量影响较大,其... 详细信息

为了对胡麻新品种(系)的丰产性、稳定性、适应性以及各试验点的辨别力进行客观评价,本研究以参加2009—2010年甘肃省胡麻区域试验的品种为材料,通过AMMI模型对其产量和脂肪酸含量进行分析。结果表明,不同的年份和环境对产量影响较大,其次是基因型。G14品种的稳定性表现最好,G10的品种稳定性最差。结合产量结果来看,G7、G2和G1的丰产性和稳产性都很好,比较适宜推广。P6对品种产量鉴别能力最强,P8对品种鉴别能力最差。从品质分析结果来看,基因型和环境作用对含油率和亚油酸含量的影响较大;亚麻酸、油酸和棕榈酸含量受年份、基因型和环境因素的影响较大;硬脂酸受基因型的影响较大。其中G2的含油率和棕榈酸含量最稳定;G8的亚油酸含量最稳定,G10的亚麻酸含量最稳定。从试验点的Di值来看,P5的含油率和油酸含量最稳定;P6的亚麻酸、硬脂酸和油酸含量最不稳定。本研究为胡麻品种选择及试验点的设置提供一定的参考依据。

关键词：胡麻产量品质 AMMI模型

Application of the Conditional Nonlinear Local Lyapunov Exponent to Second-Kind Predictability

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Advances in Atmospheric Sciences 2024年第9期41卷 1769-1786页

作者： Ming zhang Ruiqiang DING Quanjia ZHONG jianping LI Deyu LU State Key Laboratory of Earth Surface Processes and Resource Ecology(ESPRE)/Key Laboratory of Environmental Change and Natural Disasters of Chinese Ministry of EducationBeijing Normal UniversityBeijing 100875China Department of Ocean Science Hong Kong University of Science and TechnologyHong KongChina College of Oceanic and Atmospheric Sciences/Frontiers Science Center for Deep Ocean Multispheres and Earth System(DOMES)/Key Laboratory of Physical Oceanography Ministry of Education/Academy of the Future Ocean/Center for Ocean Carbon NeutralityOcean University of ChinaQingdao 266100China Laoshan Laboratory Qingdao 266237China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China College of Earth Science University of Chinese Academy of SciencesBeijing 100049China

In order to quantify the influence of external forcings on the predictability limit using observational data,the author introduced an algorithm of the conditional nonlinear local Lyapunov exponent(CNLLE)*** effectiveness of this algorithm is validated and compared with the nonlinear local Lyapunov exponent(NLLE)and signal-to-noise ratio methods using a coupled Lorenz *** results show that the CNLLE method is able to capture the slow error growth constrained by external forcings,therefore,it can quantify the predictability limit induced by the external *** this basis,a preliminary attempt was made to apply this method to measure the influence of ENSO on the predictability limit for both atmospheric and oceanic variable *** spatial distribution of the predictability limit induced by ENSO is similar to that arising from the initial conditions calculated by the NLLE *** similarity supports ENSO as the major predictable signal for weather and climate *** addition,a ratio of predictability limit(RPL)calculated by the CNLLE method to that calculated by the NLLE method was *** RPL larger than 1 indicates that the external forcings can significantly benefit the long-term predictability *** instance,ENSO can effectively extend the predictability limit arising from the initial conditions of sea surface temperature over the tropical Indian Ocean by approximately four months,as well as the predictability limit of sea level pressure over the eastern and western Pacific ***,the impact of ENSO on the geopotential height predictability limit is primarily confined to the troposphere.

关键词： conditional nonlinear local Lyapunov exponent second-kind predictability coupled Lorenz model ENSO

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混凝土碱-硅酸反应膨胀率预测模型修正研究

新型建筑材料 2024年第6期51卷 26-31页

作者：赵阳戈兵李树利张建平孙俊孙飞中国建筑科学研究院有限公司北京100013 北京市住房和城乡建设科学技术研究所北京101117 建研院检测中心有限公司北京100013 国家建筑工程技术研究中心北京100013

为建立准确、可行的混凝土棱柱体法碱-硅酸反应膨胀率预测模型,基于幂函数模型、双曲线函数模型、复合指数函数模型预测值与实测值偏差情况,分别采用拟合回归方法确定引入模型的修正参数,进而实现对幂函数、双曲线函数模型的修正,评价... 详细信息

为建立准确、可行的混凝土棱柱体法碱-硅酸反应膨胀率预测模型,基于幂函数模型、双曲线函数模型、复合指数函数模型预测值与实测值偏差情况,分别采用拟合回归方法确定引入模型的修正参数,进而实现对幂函数、双曲线函数模型的修正,评价了修正方法的准确性和可行性。结果表明:通过2组混凝土配合比180 d龄期膨胀率拟合回归分析,复合指数函数模型预测值与实测值相符性好;修正后幂函数、双曲线函数模型的拟合回归相关系数得到提高,模型所用修正方法具有一定的准确性和可行性;幂函数修正模型整体上符合程度优于其它模型,因此采用预测模型时建议优先采用幂函数修正模型。

关键词：混凝土碱-硅酸反应混凝土棱柱体法模型修正拟合回归方法