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International Journal of Minerals,Metallurgy and Materials 2009年第5期16卷 525-533页

作者： Xu Chen Cui-wei Du Xiao-gang li chuan He Ping liang lin Lu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China School of Storage and Architecture Engineering Liaoning Shihua University Fushun 113001 China

A rectangle crevice assembly was used to study the effects of cathodic protection （CP） potential, crevice thickness, holiday size, bubbling CO2, and surface condition on the chemical and electrochemical environment of the local solution under disbonded coatings. It is found that the cathodic protection removes dissolved oxygen from the crevice and thus shifts the solution to a more al- kaline state. Furthermore, the potential of the steel reaches the protected potential range. The available protection distance increases with the negative applying potential. The steady potential and pH distribution are easily achieved, but the polarization degree is not satisfied within the thinner crevice. The difference in the solution environment is found to correlate to the holiday size. The smaller the holiday, the smaller the difference is. The presence of CO2 inhibits the formation of an alkaline environment. It is also found that the rust layer dramatically decreases the polarization rate in the crevice.

关键词： pipeline steel polarization cathodic protection crevice corrosion

Synthesis and Crystal Structure of a Novel Tetravanadate Modified by Chiral Racemoid Zirconium Complex

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Chinese Journal of Structural Chemistry 2006年第8期25卷 979-984页

作者： WANG Qing-wei SHI lin-Fang GAO Guang-Gang li chuan-Bi EAN liang Chemistry College Jilin Normal University Siping 136000 China Chemistry College Jilin University Changchun 130000 China

[Zr（phen）4（H2O）4O2（V4O12）]（phen）2 1 （phen = 1,10-phenanthroline） was synthesized under hydrothermal condition. The crystal of 1 belongs to triclinic, space group P1^- with a = 10.6334（8）, b = 11.9201（8）, c = 14.6505（10） A, α = 69.9980（10）, β = 84.9240（10）, γ = 84-1300（10）°, V = 1733.0（2） A^3, Z = 1, Mr = 1672.27, Dc = 1.602 g/cm^3, C72H56N12O18V4Zr, F（000） = 848, μ（MoKa） = 0.747 mm^-1, S = 0.957, R = 0.0504 and wR = 0.1173 for 4011 observed reflections （1 〉 20（I））. The crystal structure of 1 could be discussed in terms of {Zr（phen）2（H2O）2O2}, un-coordinated 1,10-phenanthroline molecules and { V4O12 } unit. In { Zr（phen）2（H2O）2O2 }, the coordination geometry of zirconium is a dodecahedron, but {V4O12} unit is constructed from four apex-sharing {VO4} tetrahedra. Furthermore, {V4O12} links with two {Zr（phen）2（H2O）2O2} units via two bridging oxygen atoms. Interestingly, the two {Zr（phen）2（H2O）2O2} units display D- and L-enantiomers, respectively, upon which the whole molecule represents a racemoid configuration.

关键词： crystal structure V-O tetrahedron 1,10-phenanthroline

Fabrication and characterization of NiO films for energetic nano-multilayers by direct current reactive sputtering

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Rare Metals 2018年第7期37卷 594-598页

作者： Yi-Chao Yan wei Shi Hong-chuan Jiang Jie Xiong Wan-li Zhang State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China

NiO films were fabricated by reactive direct current magnetron sputtering on glass and alumina substrates for the application in energetic nano-multilayers. The structural and thermal properties of the films were investigated with the volume ratio of oxygen to argon ranging from 1：9 to 3：2, and the optimized ratio value is obtained as 1：3, which was confirmed by X-ray diffraction （XRD）, atomic force microscopy and ultrafast measure- ment system. The effect of the film thickness, varying from 150 to 900 nm, on the structural properties was characterized by XRD and scanning electron microscopy （SEM）. XRD analysis reveals that the （111） lattice plane is the preferred orientation. The intensities of preferential peaks and the grain sizes increase as the film thicknesses increase.

关键词： NiO films Energetic nano-multilayers Thermal properties Volume ratio of oxygen to argon

Effect of Biodiesel Soot on Tribological Behavior of liquid Paraffin

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China Petroleum Processing & Petrochemical Technology 2018年第3期20卷 106-113页

作者： li chuan wei Daozhu Zhuang Yuan Song Ruhong Hu Xianguo School of Mechanical Engineering Hefei University of Technology School of Automobile and Transportation Engineering Hefei University of Technology

Biodiesel soot （BDS） was collected from the combustion of biodiesel using a self-made soot trap. The effect of BDS on the txibological behavior of liquid paraffin （LP） was investigated using a four-ball txibometer. A rotating viscometer was used to investigate the effect of BDS on the viscosity of LE The morphology, composition, and tribological mechanism of BDS were studied by means of FETEM, XRD, XPS, SEM/EDS, and the 3D laser scanning microscopy. Test results showed that the BDS aggregates were chain-like, and the average diameter of BDS was 35 nm. The BDS existed in the form of graphitic layers and amorphous carbon. The oxygen-containing functional groups in BDS consisted of the （C-O-C） and （C-O-H）. With an increasing BDS content, the dynamic viscosity of LP increased and the maximum non-seizure load increased initially and became stable later. In addition, the average wear scar diameter （AWSD） of LP increased and the average friction coefficient of LP decreased at first and then increased later. The tribological mechanisms could be ascribed to the variation in content of BDS： BDS could act as a friction modifier for a lower friction coefficient in case of low BDS content. However, the BDS aggregates could lead to increase of abrasive wear to influence the lubricating oil film at higher content of BDS, which would reduce the friction reduction ability and wear resistance of LP.

关键词： biodiesel soot tribological behavior liquid paraffin

Testing Serial Correlation in Partially linear Additive Models

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Acta Mathematicae Applicatae Sinica 2019年第2期35卷 401-411页

作者： Jin YANG chuan-hua wei School of Statistics and Data Science Nankai University Department of Applied Mathematics The Hong Kong Polytechnic University Department of Statistics School of ScienceMinzu University of China

As an extension of partially linear models and additive models, partially linear additive model is useful in statistical modelling. This paper proposes an empirical likelihood based approach for testing serial correlation in this semiparametric model. The proposed test method can test not only zero first-order serial correlation, but also higher-order serial correlation. Under the null hypothesis of no serial correlation, the test statistic is shown to follow asymptotically a chi-square distribution. Furthermore, a simulation study is conducted to illustrate the performance of the proposed method.

关键词： Partially linear additive model Backfitting Profile least-squares approach Empirical likelihood Serial correlation

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双针-板结构脉冲气泡放电等离子体固氮研究

原子与分子物理学报 2025年第6期42卷 122-128页

作者：赵少伟张丽方志南京工业大学电气工程与控制科学学院南京211816

大气压低温等离子体可以利用空气直接进行氧化固氮,具有反应条件温和、参数灵活可控、避免温室气体排放等优点.本文利用双针-板电极在水中形成气泡放电等离子体,以空气为放电气体进行了固氮研究,分析了产物浓度和固氮能耗的影响因素.研... 详细信息

大气压低温等离子体可以利用空气直接进行氧化固氮,具有反应条件温和、参数灵活可控、避免温室气体排放等优点.本文利用双针-板电极在水中形成气泡放电等离子体,以空气为放电气体进行了固氮研究,分析了产物浓度和固氮能耗的影响因素.研究结果表明,等离子体中含有丰富的氮原子、氧原子、氢原子、激发态氮分子等活性物种,可高效合成硝态含氮产物.研究发现,脉冲参数、电极间隙、工作气体组分对气泡放电等离子体的固氮性能有重要影响.装置最高NO~-_x合成速率为19.2μmol/min,最小能耗约为11 MJ/mol.此外还发现,电极间隙为6 mm时,固氮性能最优;空气中增加适量氧气(氧气/氮气比例为0.4)可以增强产物合成,降低能耗.

关键词：低温等离子体纳秒脉冲放电气液放电固氮

乳清蛋白-果胶高内相乳液凝胶对低脂再制奶酪的品质影响

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食品科学 2025年第2期46卷 57-64页

作者：李红娟李振任钏袁玉京李可邱晓豹李洪波于景华天津科技大学食品科学与工程学院食品营养与安全国家重点实验室天津300457

以乳清蛋白和果胶、葡聚糖为主要原料,采用酸诱导法制备乳清蛋白-果胶乳液凝胶(whey protein-pectin emulsion gel,WP)和乳清蛋白-葡聚糖乳液凝胶(whey protein-glucan emulsion gel,WG),比较35%、75%分散相体积分数凝胶(分别记为WP35、... 详细信息

以乳清蛋白和果胶、葡聚糖为主要原料,采用酸诱导法制备乳清蛋白-果胶乳液凝胶(whey protein-pectin emulsion gel,WP)和乳清蛋白-葡聚糖乳液凝胶(whey protein-glucan emulsion gel,WG),比较35%、75%分散相体积分数凝胶(分别记为WP35、WG35、WP75、WG75)的功能特性,并进一步探究高内相乳液凝胶作为脂肪替代物在低脂再制奶酪中的代脂效果。结果表明:WP75的平均粒径最小,脂肪分布均匀,蛋白质网络结构稳定。乳液凝胶样品在0.1~10 Hz内弹性模量(G′)和黏性模量(G″)都随油相体积分数的升高呈上升趋势,其中WP75抵抗形变能力、热稳定性及持水性都优于其他样品。样品15%-WP75(添加WP75,脂肪质量分数15%的再制奶酪)油析性减弱,熔化性增强,质构特性与全脂对照无明显差异。研究表明乳清蛋白与果胶制备的高内相乳液凝胶在低脂奶酪产品有较好的脂肪替代效果,在低脂乳制品加工中具有良好的应用潜力。

关键词：乳清蛋白果胶葡聚糖高内相乳液凝胶低脂再制奶酪

Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study

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Neural Regeneration Research 2025年第10期20卷 3013-3024页

作者： Kaixuan Zhou Gaoxiong Duan Ying liu Bei Peng Xiaoyan Zhou lixia Qin lingyan liang Yichen wei Qingping Zhang Xiaocheng li Haixia Qin Yinqi Lai Yian Lu Yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming Zhao Jun liu Jianrong Yang Demao Deng Guangxi Key Laboratory of Special Biomedicine School of MedicineGuangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology the People’s Hospital of Guangxi Zhuang Autonomous RegionGuangxi Academy of Medical SciencesNanningGuangxi Zhuang Autonomous RegionChina Department of Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Guangxi Clinical Research Center for Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina

Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 *** studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase *** a result,little is known about the pathophysiology of sleep disturbances in the acute phase of *** address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this *** COVID-19 patients with sleep disturbances were included in a longitudinal *** found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain *** cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index ***,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy *** 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep *** findings indicate that the sleep disturbances patients had altered morphology in the cortical an

关键词： brain structure cortical gray matter volume cortical surface area cortical thickness hippocampus magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume

参与食品可追溯体系对农户绿色生产转型的影响

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西北农林科技大学学报（社会科学版） 2025年第1期25卷 89-100页

作者：陈哲李晓静司伟西北农林科技大学经济管理学院陕西杨凌712100 烟台大学经济管理学院山东烟台264005 中国农业大学经济管理学院北京100083

基于2022年山东和陕西2省6县(市、区)1 248户苹果种植户的微观调查数据,在使用有限混合模型(FMM)测度农户绿色生产转型程度的基础上,实证检验参与食品可追溯体系对农户绿色生产转型的影响。研究结果表明:(1)参与食品可追溯体系会显著促... 详细信息

基于2022年山东和陕西2省6县(市、区)1 248户苹果种植户的微观调查数据,在使用有限混合模型(FMM)测度农户绿色生产转型程度的基础上,实证检验参与食品可追溯体系对农户绿色生产转型的影响。研究结果表明:(1)参与食品可追溯体系会显著促进农户绿色生产转型,这一结论在解决潜在的内生性问题和经过多种稳健性检验后依然成立;(2)异质性分析表明,参与食品可追溯体系对大规模种植户、参与组织和受教育水平更高的农户绿色生产转型的促进作用更为明显;(3)机制分析结果表明,参与食品可追溯体系可以通过产品收益激励、绿色认知提升、社会声誉维护三条路径影响农户绿色生产转型。据此提出加大食品可追溯体系建设,提高农户参与比率;明晰转型关键制约因素,增强农户绿色生产转型意愿;充分考虑不同资源禀赋农户特征,给予针对性的政策引导等对策建议。

关键词：食品可追溯体系绿色生产转型溢价激励随机前沿模型苹果种植户

湿地表层底泥溶解性有机质荧光组分特征及与真菌群落相关性

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光谱学与光谱分析 2025年第1期45卷 191-196页

作者：史传奇李艳孟令波胡钰金梁哈尔滨学院黑龙江省寒区湿地生态与环境研究重点实验室黑龙江哈尔滨150086 北京市农林科学院植物营养与资源环境研究所北京100097 东北农业大学资源与环境学院黑龙江哈尔滨150038

溶解性有机质(DOM)和微生物群落间具有紧密联系,DOM为微生物提供营养,微生物代谢可转化DOM,两者间相互作用共同影响着生态系统的物质循环与能量流动。采集北方寒区天然湿地(河流湿地,HL;湖泊湿地,HP)和人工湿地(水田,ST;鱼塘,YT)表层(0~... 详细信息

溶解性有机质(DOM)和微生物群落间具有紧密联系,DOM为微生物提供营养,微生物代谢可转化DOM,两者间相互作用共同影响着生态系统的物质循环与能量流动。采集北方寒区天然湿地(河流湿地,HL;湖泊湿地,HP)和人工湿地(水田,ST;鱼塘,YT)表层(0~15 cm)底泥样品,采用三维荧光光谱法和高通量测序技术,揭示不同类型湿地表层底泥DOM荧光光谱及真菌群落特征,并进一步分析其相关性。结果表明:表层底泥DOM荧光光谱共识别出4种荧光组分,包括类富里酸(C1)、类胡敏酸(C2)和类蛋白质(类色氨酸C3和类酪氨酸C4)。C1和C2成显著正相关,而与类蛋白质间相关性不显著。C1的相对浓度高于C2,C3和C4的相对浓度接近。YT中DOM浓度相对高于其余样品,HL和HP中C2和类蛋白质相对浓度具有显著差异,ST和YT中C1、C2和C3的相对浓度均具有显著差异。湿地表层底泥真菌群落优势门(除未分类类群)为子囊菌门(Ascomycota)、担子菌门(Basidiomycota)、罗兹菌门(Rozellomycota)。YT中真菌群落Chao1丰富度指数、Shannon多样性指数显著较低,而Simpson优势度指数显著较高,HP中Shannon多样性指数显著高于其余样品。C1、C2与真菌群落多样性显著相关,C2与真菌群落组成显著相关,而类蛋白质与真菌群落无显著相关性。C1、C2与子囊菌门均成显著正相关,C1与壶菌门(Chytridiomycota)和单毛壶菌门(Monoblepharomycota)成显著负相关,C2与担子菌门、罗兹菌门、壶菌门、单毛壶菌门均成显著负相关。因此,真菌群落对DOM相对大分子量荧光组分的相对浓度具有显著影响。针对北方寒区典型湿地表层底泥DOM荧光光谱特征及与真菌群落相关性进行分析,为湿地环境监测与评价提供基础数据,并为湿地合理利用提供理论参考。

关键词：三维荧光光谱溶解性有机质荧光组分真菌