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牙尖斜面夹角与牙隐裂关系的危险因素分析

口腔颌面修复学杂志 2024年第5期25卷 337-341页

作者：王凯红马俪嘉王静平顶山市口腔医院医学影像科平顶山467000 郑州大学第一附属医院牙体牙髓科郑州450000

目的:采用锥形束计算机断层扫描技术(cone beam computed tomography,CBCT)测量牙尖斜面夹角,分析牙尖斜面夹角与牙隐裂的关系及牙隐裂的危险因素。方法:选取2020年5月~2022年5月本院上颌第一磨牙隐裂老年患者50例为研究组,另同期随机... 详细信息

目的:采用锥形束计算机断层扫描技术(cone beam computed tomography,CBCT)测量牙尖斜面夹角,分析牙尖斜面夹角与牙隐裂的关系及牙隐裂的危险因素。方法:选取2020年5月~2022年5月本院上颌第一磨牙隐裂老年患者50例为研究组,另同期随机选取个别正常老年人40例为对照组。均行CBCT检查,测量上颌第一磨牙近中颊舌牙尖斜面夹角、远中颊舌牙尖斜面夹角。通过调查问卷的方式对牙隐裂可能影响因素进行统计分析,探讨引起牙隐裂发生的危险因素,并评估近、远中颊舌牙尖斜面夹角对牙隐裂诊断价值。结果:研究组上颌第一磨牙近、远中颊舌牙尖斜面夹角小于对照组(P<0.05);Logistic回归分析,结果显示习惯性咬硬物、偏侧咀嚼习惯、喜食质地粗糙坚韧食物、近中颊舌牙尖斜面夹角、远中颊舌牙尖斜面夹角是牙隐裂发生的影响因素(P<0.05);受试者工作特征(receiver operating characteristic,ROC)曲线分析显示,近中颊舌牙尖斜面夹角、远中颊舌牙尖斜面夹角诊断牙隐裂曲线下面积(area under curve,AUC)(95%CI)分别为0.937(0.866~0.978)、0.811(0.714~0.885)。结论:近中颊舌牙尖斜面夹角、远中颊舌牙尖斜面夹角是老年患者第一磨牙牙隐裂风险因素。

关键词：牙隐裂锥形束状计算机断层扫描技术牙尖斜面夹角

Gene Expression Profiling Related to Hyphal Growth in a Temperature-Sensitive Mutant of Magnaporthe oryzae

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Journal of Integrative Agriculture 2013年第12期12卷 2189-2196页

作者： LI Xue-song XU Fei wang hong-kai LIN Fu-cheng State Key Laboratory for Rice Biology Biotechnology InstituteZhejiang University Bioinformatics Lab Institute of Digital AgricultureZhejiang Academy of Agricultural Sciences

The rice blast,caused by fungus Magnaporthe oryzae,is a major constraint to the world food *** growth is the foundation of fungal development and proliferation of *** investigate genes involved in hyphal growth of this fungus,digital gene expression tag profiling was used to compare a previously generated temperature-sensitive mutant which defect at hyphae growth and reduction on pathogenicity,with its related wildtype strain.416 genes were detected as differential expression,178 of which were specifically expressed in Guy-11 but down-regulated expression in the *** classification analysis revealed the phenotype mutation may be mainly caused by a defection in translational and vacuole- related *** results and the protocol used will improve our knowledge on morphogenesis and promote the further study on *** pathogenesis.

关键词： differential expressed gene qRT-PCR gene ontology hyphal growth vacuole

浅析水轮机调速器压力油罐改造的主要参数计算

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水电站机电技术 2024年第1期47卷 67-69,75页

作者：王红凯唐林钧吕传宝周杰贵州乌江水电开发有限责任公司东风发电厂贵州清镇551400 中国电建集团贵阳勘测设计研究院有限公司贵州贵阳550081

东风发电厂调速器压力油罐投运至今接近30年,超出了设计使用年限,存在较大的安全隐患,每年需进行安全检测及维护,期间影响电厂机组的正常运行,增加了运行和时间成本。结合电厂实际需要对压力油罐改造优化,进行容积、压力等级及强度等参... 详细信息

东风发电厂调速器压力油罐投运至今接近30年,超出了设计使用年限,存在较大的安全隐患,每年需进行安全检测及维护,期间影响电厂机组的正常运行,增加了运行和时间成本。结合电厂实际需要对压力油罐改造优化,进行容积、压力等级及强度等参数计算以满足相关规范要求,提高调速器供油的可靠性,为机组稳定运行提供保障,为类似工程的改造提供一定的参考。

关键词：改造压力油罐容积压力等级强度

维普期刊数据库博看期刊

Characterization of Nutrients,Heavy Metals,Petroleum and Their Impact on Phytoplankton in Laizhou Bay:Implications for Environmental Management and Monitoring

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Journal of Ocean University of China 2024年第3期23卷 822-834页

作者： wang kai ZHAO Linlin ZHU Yugui YANG Liqiang wang Yunfeng hong Xuguang College of Marine Life Science Ocean University of ChinaQingdao 266003China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China College of Fisheries Ocean University of ChinaQingdao 266003China Institute of Oceanology Chinese Academy of SciencesQingdao 266071China Southern Marine Science and Engineering Guangdong Laboratory Guangzhou 511458China

The Laizhou Bay(LB)represents a substantial ecological area that is vulnerable to human activities and confronts diverse environmental *** study provides a comprehensive characterization of nutrients,petroleum,heavy metals,and phytoplankton community structure across seven distinct areas in *** results indicate relatively high concentrations of NO_(2)-N,SiO_(4)-Si,and NO_(3)-N in the Southwest Laizhou Bay(SWLB)and Huanghe River Estuary(HRE).In contrast,the East Laizhou bay(ELB)and the North of Huanghe River Estuary(NHRE)exhibit the highest concentrations of heavy metals(As,Cr and Hg).The areas with high phytoplankton density and community diversity are mainly located in the *** adjusting for basic environmental factors,phytoplankton density and Margalef richness index D are significantly associated with nutrients(NO_(3)-N,NO_(2)-N,NH_(4)-N,SiO_(4)-Si),and heavy metal(Cr)*** highlight that,in addition to Xiaoqinghe River,nutrients brought by the Mihe River in the SWLB and heavy metal(Cr)pollution in the ELB resulting from industrial and mining activities along the coast significantly influence phytoplankton growth and community ***,it is recommended that more monitoring and management efforts be focused on these regions in the future.

关键词： Huanghe River Estuary Laizhou Bay nutrients heavy metals phytoplankton biodiversity

Electrolyte Design for Low‑Temperature Li‑Metal Batteries:Challenges and Prospects

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Nano-Micro Letters 2024年第2期16卷 365-382页

作者： Siyu Sun Kehan wang Zhanglian hong Mingjia Zhi kai Zhang Jijian Xu Department of Chemistry City University of Hong KongHong Kong 999077People’s Republic of China State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China State Key Laboratory of Advanced Chemical Power Sources Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)Haihe Laboratory of Sustainable Chemical TransformationsCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)College of ChemistryNankai UniversityTianjin 300071People’s Republic of China Department of Chemical and Biomolecular Engineering University of Maryland College ParkCollege ParkMD 20742USA

Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature *** get the most energy storage out of the battery at low temperatures,improvements in electrolyte chemistry need to be coupled with optimized electrode materials and tailored electrolyte/electrode ***,this review critically outlines electrolytes’limiting factors,including reduced ionic conductivity,large de-solvation energy,sluggish charge transfer,and slow Li-ion transportation across the electrolyte/electrode interphases,which affect the low-temperature performance of Li-metal *** theoretical derivations that explain the explicit influence of temperature on battery performance are presented to deepen *** improvement strategies from the aspects of electrolyte design and electrolyte/electrode interphase engineering are summarized and rigorously *** on future research are proposed to guide the ongoing exploration for better low-temperature Li-metal batteries.

关键词： Solid electrolyte interphase Li metal Low temperature Electrolyte design Batteries

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测量弹性体碰撞的光子多普勒测速仪

光学与光电技术 2024年第4期22卷 7-13页

作者：高瑞休刘岚岚王健王凯宏黄子赫吴重庆北京交通大学唐山研究院发光与光信息技术教育部重点实验室北京100044 北京交通大学物理科学与工程学院北京100044 南京恒高光电研究院有限公司江苏南京210046

弹性体碰撞过程的研究对于缓冲减震应用有重要意义,但因为存在反弹现象,过程复杂,一般设备不能很好地测量。提出一种双光源的频移光子多普勒测速仪(Photonic Doppler Velocimetry,PDV)研究弹性弹丸的碰撞过程。使用两个激光器提供的信... 详细信息

弹性体碰撞过程的研究对于缓冲减震应用有重要意义,但因为存在反弹现象,过程复杂,一般设备不能很好地测量。提出一种双光源的频移光子多普勒测速仪(Photonic Doppler Velocimetry,PDV)研究弹性弹丸的碰撞过程。使用两个激光器提供的信号光和参考光产生差频信号,解析得到速度的大小和方向。实验结果表明:弹丸撞击钢板后速度在0.1 ms内降为零,并在回弹后1 ms出现了多次的往返运动。通过监测两个激光器的频差,可在一定程度上减小激光器频率不稳而引起的误差。

关键词：弹性体碰撞光子多普勒测速外差激光干涉测量频移PDV 回弹运动

Evolution hydrothermal aging resistance mechanism study of zirconium and manganese doped CeO_(2)catalysts in soot catalytic combustion based on low Miller indices crystal surface effect

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Journal of Rare Earths 2024年第7期42卷 1272-1281,I0003页

作者： Zonglin Li Pan wang hong Ni Chengcheng Ao Lidong Zhang Hefeng Zhang kai Li School of Automotive and Traffic Engineering Jiangsu UniversityZhenjiang212013China State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation Chinese Research Academy of Environmental ScienceBeijing100012China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei230026China

The thermogravimetric analysis(TGA)experiments were carried out to reveal the mechanism of Zr and Mn doping on catalytic activity of CeO_(2)catalyst both fresh and after hydrothermal aging,and the lattice morphology and valence changes were characterized by means of Brunauer-Emmett-Teller(BET)method,X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),and H_(2)-temperature programmed reduction(H_(2)-TPR).Density functional theory(DFT)and molecular thermodynamics calculations were applied to investigate the change in catalytic activity,crystal surface energy and crystal morphology caused by hydrothermal *** maximum reaction rate temperature of fresh Mn/CeO_(2)(389℃)is similar to that of CeO_(2)(371℃)and lower than that of Zr/CeO_(2)(447℃),but the catalytic performance of CeO_(2)decreases more severely after hydrothermal *** catalyst crystals show different degrees of crystal surface migration after hydrothermal aging,which leads to the reduction of Ce^(3+)/Ce^(4+) ratio and the active sites *** calculations indicate that the doping of Zr and Mn reduces the surface energy of the low Miller indices surface and increases the oxygen vacancy formation energy,leading to better thermal stability and lower catalytic *** Zr and Mn doping also changes the adsorption energy and Gibbs free energy of H_(2)O,which dominates the migration of(111)to(110)and(100)in the vapor *** crystal surface migration mechanism of CeO_(2)catalysts doped with Zr and Mn induced by H_(2)O molecules at high temperature obtained in this study can provide a valuable addition to the regeneration of CeO_(2)catalysts in the after-treatment systems of diesel engines.

关键词： Soot CeO_(2)-based catalyst CDPF Rare earth metal oxides DFT calculations

On Klein tunneling of low-frequency elastic waves in hexagonal topological plates

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1139-1154页

作者： Yuxin YAO Yuansheng MA Fang hong kai ZHANG Tingting wang Haijun PENG Zichen DENG School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China MIIT Key Laboratory of Dynamics and Control of Complex Systems Northwestern Polytechnical UniversityXi’an710072China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian116024Liaoning ProvinceChina

Incident particles in the Klein tunnel phenomenon in quantum mechanics can pass a very high potential *** the concept of tunneling into the analysis of phononic crystals can broaden the application *** this study,the structure of the unit cell is designed,and the low frequency(<1 k Hz)valley locked waveguide is realized through the creation of a phononic crystal plate with a topological phase transition *** defect immunity of the topological waveguide is verified,that is,the wave can propagate along the original path in the cases of impurities and ***,the tunneling phenomenon is introduced into the topological valley-locked waveguide to analyze the wave propagation,and its potential applications(such as signal separators and logic gates)are further explored by designing phononic crystal *** research has broad application prospects in information processing and vibration control,and potential applications in other directions are also worth exploring.

关键词： topological metamaterial elastic wave Klein tunneling valley-locked waveguide

Threshold of climate extremes that impact vegetation productivity over the Tibetan Plateau

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Science China Earth Sciences 2024年第6期67卷 1967-1977页

作者： Zhenggang PIAO Xiangyi LI Hao XU kai wang Shuchang TANG Fei KAN Songbai hong College of Urban and Environmental Sciences Peking UniversityBeijing 100871China

Vegetation growth is adversely impacted by multiple climate extremes related to the water and thermal stress over the Tibetan Plateau(TP).However,it remains unknown at which stress level these climate extremes can trigger the abrupt shifts of vegetation response to climate extremes and result in the maximum vegetation response across *** fill this knowledge gap,we combined the hydrometeorological data and the satellite-derived vegetation index to detect two critical thresholds that determine the response of vegetation productivity to droughts,high-temperature extremes,and low-temperature extremes,respectively,during *** results show that the response of vegetation productivity to droughts rapidly increases once crossing -1.41±0.6 standard deviation(σ)below the normal conditions of soil *** crossing-2.98σ±0.9σ,vegetation productivity is maximum damaged by ***-temperature extremes,which have the two thresholds of 1.34σ±0.4σand 2.31σ±0.4σover TP,are suggested to trigger the strong response of vegetation productivity at a milder stress level than low-temperature extremes(two thresholds:-1.44σ±0.5σand-2.53σ±0.8σ).Moreover,we found the compounded effects of soil moisture deficit in reducing the threshold values of both high-and low-temperature *** on the derived thresholds of climate extremes that impact vegetation productivity,Earth System Models project that southwestern TP and part of the northeastern TP will become the hotspots with a high exposure risk to climate extremes by *** study deciphers the high-impact extreme climates using two important thresholds across TP,which advances the understanding of the vegetation response to different climate extremes and provides a paradigm for assessing the impacts of climate extremes on regional ecosystems.

关键词： Tibetan Plateau Climate extremes Thresholds Vegetation productivity