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On traceable iterated line graph and hamiltonian path index

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 239-252页

作者： NIU Zhao-hong XIONG Li-ming YANG Wei-hua School of Mathematical Sciences Shanxi UniversityTaiyuan 030006China School of Mathematics and Statistics Beijing Key Laboratory on MCAACIBeijing Institute of TechnologyBeijing 100081China Department of Mathematics Taiyuan University of TechnologyTaiyuan 030024China

Xiong and Liu[21]gave a characterization of the graphs G for which the n-iterated line graph L^(n)(G)is hamiltonian,for n≥*** this paper,we study the existence of a hamiltonian path in L^(n)(G),and give a characterization of G for which L^(n)(G)has a hamiltonian *** applications,we use this characterization to give several upper bounds on the hamiltonian path index of a graph.

关键词： iterated line graph traceable hamiltonian index hamiltonian path index

Unraveling role of double-exchange interaction in electrochemical water oxidation by external magnetic field

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Rare Metals 2024年第1期43卷 289-297页

作者： Jun Li Jun-ming Li hong hong Dong-Xue Liu Qing-Qi Cao Dun-Hui Wang National Laboratory of Solid State Microstructures and Jiangsu Provincial Key Laboratory for Nanotechnology Nanjing UniversityNanjing 210093China School of Electronics and Information Hangzhou Dianzi UniversityHangzhou 310018China

Double-exchange(DE) interaction plays an important role in electrocatalytic oxygen evolution reaction(OER).However,precise achievement of DE interaction often requires foreign dopants or vacancy engineering,leading to destabilization of the catalysts and deterioration of *** contrast,the utilization of environmentally friendly,contactless,and continuously adjustable magnetic fields to study the OER process is profitable to avoid aforementioned interference factors and further elucidate the direct relationship_(0.5)between DE interaction and OER ***,by using cobalt hydroxide carbonate(Co(OH)(CO_(3))·xH_(2)O,CoHC) nanostructures as a proof-of-concept study,external magnetic fields are carefully implemented to verify the role of DE interaction during water oxidation *** studies reveal that external magnetic fields effectively enhance the reaction rate of the catalyst,the overpotential decreases from 386 to 355 mV(100 mA·cm^(-2)),while Tafel slopes drastically decline from 93 to 67 mV·dec^(-1)(1.0 T).Moreover,magnetic field increment exhibits robust *** in situ Raman and impedance measurements under external field,it can be found that magnetic field promotes the electron migration between Co^(2+) and Co^(3+) in the CoHC catalysts with the assistance of DE interactions,thus boosting the OER efficiency.

关键词： Magnetic field Double-exchange(DE)interaction Electrocatalysis Oxygen evolution reaction(OER) Cobalt hydroxide carbonate

2022年4月云南罕见寒潮天气成因及预报偏差分析

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云南大学学报（自然科学版） 2024年第1期46卷 82-93页

作者：连钰杨素雨马文倩赵宁坤张秀年晏红明云南省气象台云南昆明650034 中国气象局横断山区(低纬高原)灾害性天气研究中心云南昆明650034 云南省气候中心云南昆明650034

2022年3月31日—4月2日,云南省出现历史同期罕见的寒潮天气过程.通过地面观测资料、高空观测资料和NCEP FNL资料,对此次寒潮过程的成因进行分析,并对欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts,ECMWF)... 详细信息

2022年3月31日—4月2日,云南省出现历史同期罕见的寒潮天气过程.通过地面观测资料、高空观测资料和NCEP FNL资料,对此次寒潮过程的成因进行分析,并对欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts,ECMWF)模式的形势场及最低气温进行检验.结果表明:此次寒潮过程发生在北极涛动负位相期间,西伯利亚高压偏强,欧亚中高纬形成两槽一脊的环流形势.东亚大槽后侧强劲的偏北风引导低层冷空气南移,南支槽向东移动为云南省输送暖湿气流,700 hPa切变线和地面冷锋的南侵,共同造成了此次寒潮天气过程的发生;此次寒潮过程的强降温是由过程中近地层强冷平流的作用,冷锋后部较强的垂直上升运动,引起绝热膨胀冷却作用,加剧了局地气温的下降;通过定量分析导致昆明局地气温变化的各项因子发现,昆明的降温主要受温度平流项的影响,其次是非绝热项的影响. ECMWF模式能较好地预报此次寒潮过程的高低空环流形势及降温的范围,但对降温强度的预报效果相对较差.

关键词：寒潮云南成因分析北极涛动预报偏差

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野生垂穗披碱草种质资源抗旱性筛选与评价

草地学报 2024年第7期32卷 2158-2168页

作者：罗鑫闫利军李达旭游明鸿张建波季晓菲雷雄白史且常丹四川省草原科学研究院四川成都611731 西南科技大学四川绵阳621010 长汀县农业农村局福建长汀366399

为探究垂穗披碱草(Elymus nutans Griseb.)苗期对干旱胁迫的响应,筛选出耐旱材料,本试验选取内蒙、甘肃、四川等不同地区不同生境来源的9份野生垂穗披碱草种质材料为研究对象,采用自然干旱法对垂穗披碱草幼苗进行为期35 d的干旱复水处... 详细信息

为探究垂穗披碱草(Elymus nutans Griseb.)苗期对干旱胁迫的响应,筛选出耐旱材料,本试验选取内蒙、甘肃、四川等不同地区不同生境来源的9份野生垂穗披碱草种质材料为研究对象,采用自然干旱法对垂穗披碱草幼苗进行为期35 d的干旱复水处理。通过分析幼苗叶片的形态表型和生理指标的含量变化,采用隶属函数法和聚类分析综合评价了9份垂穗披碱草的抗旱性。研究发现:在干旱胁迫下,9份垂穗披碱草的植株表型和生理特性均受到不同程度的影响,表现为叶片相对含水量、叶绿素含量和最大光化学效率(Fv/Fm)下降,细胞膜透性和抗氧化酶活性升高以及渗透调节物质的积累。9份垂穗披碱草的抗旱性强弱顺序依次为NM037>XJ027>HB013>XZ010>GS007>QH011>GS005>SC021>SC020。本研究表明,材料NM037能更好地适应干旱胁迫的处理,表现出更强的抗旱能力,可作为抗旱型垂穗披碱草育种的参考对象,这为人工草地建植、草地生产力的提高和生态修复提供依据。

关键词：垂穗披碱草干旱胁迫复水抗旱性

Apple stem grooving virus is associated with leaf yellow mottle mosaic disease on Citrus grandis cv. Huangjinmiyou in China

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Journal of Integrative Agriculture 2022年第7期21卷 2031-2041页

作者： XUAN Zhi-you ZHANG Song LI Ping YANG Fang-yun CHEN hong-ming LIU Ke-hong ZHOU Yan LI Zhong-an ZHOU Chang-yong CAO Meng-ji National Citrus Engineering and Technology Research Center Citrus Research InstituteSouthwest UniversityChongqing 400712P.R.China State Cultivation Base of Crop Stress Biology for Southern Mountainous Land Academy of Agricultural SciencesSouthwest UniversityChongqing 400715P.R.China

Although it is usually latent on citrus, apple, and pear, apple stem grooving virus(ASGV) poses a great risk to many sensitive cultivars. Since severe leaf yellow mottle mosaic(LYMM) symptoms have been observed on Huangjinmiyou(HJY) pummelos(Citrus grandis cv. Huangjinmiyou), a commercial variety that is widely cultivated in South China, high throughput sequencing(HTS) was used to find potential pathogens and only three divergent ASGV variants were identified. The three ASGV variants shared 81.03–82.34% genome-wide pairwise identities with each other, and were separately closest to other ASGV variants from different hosts and/or geographical regions, as indicated by viral phylogenies. However, these new variants may have developed from viral interstrain interactions, based on the results of recombination analysis. A large-scale survey using reverse transcription-PCR(RT-PCR) protocols designed for the three ASGV variants revealed a high incidence(92.7–100%) of ASGV in symptomatic HJY trees from 11 major citrusproducing regions in China. None of ASGV were detected in asymptomatic trees. Temperature treatments applied to the symptomatic HJY plants showed that ASGV is sensitive to high temperatures(30–35°C), at which not only the plants recovered, but also the viruses were not detected by RT-PCR, while at low temperatures(20–24°C), both the symptoms and viruses remained detectable. These data show that ASGV is associated with the LYMM disease prevalent on HJY in China, and this is the significant basis especially of taking appropriate measures timely to manage the disease.

关键词： citrus pummelo apple stem grooving virus genome sequence thermotherapy

Agglomeration and bonding mechanism of typical metallurgical solid wastes

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Journal of Iron and Steel Research(International) 2023年第7期30卷 1390-1400页

作者： Ting Wu Yu-qi Kong Jiu-chang Zhang Xin-yu Wang Lei Ma Tao Yang Jie Lei hong-ming Long School of Metallurgical Engineering Anhui University of TechnologyMa’anshan 243032AnhuiChina Key Laboratory of Metallurgical Emission Reduction&Resources Recycling(Anhui University of Technology) Ministry of EducationMa’anshan 243032AnhuiChina

The agglomeration of solid wastes is a key factor for subsequent utilization,while the difficulty in agglomeration and high cost have become common problems in the recycling *** disk pelletizing process was adopted,based on the optimization method by liquid binder addition,and the influence mechanism of the ratio of typical solid wastes as blast furnace dust(BFD)and sludge generated by oxygen converter gas recovery(OGS)was ***,the effect of binder solution concentration on the quality of green pellets was *** from the contact angle detection and infrared spectrum analysis,the liquid bridge model was established to study the bonding *** results showed that OGS had stronger adsorption effect with binder,and the hydrophilicity of BFD was *** the concentration of binder was higher than 0.2 wt.%,the contact angle between the binder and BFD was bigger than that with OGS,while the capillary force between particles reduced with larger contact *** increment in the binder concentration increased the viscous force between particles and the maximum separation *** ultimate drop strength and compressive strength were related to the type of viscous force,and the compressive strength reflected the strength of the force between particles intuitively,while the drop strength represented the comprehensive forces of green *** combination of BFD and OGS was available for pelletizing process,while the ratio of BFD should not exceed 32.0%,and binder C was added in the form of solution with the addition amount of 0.4 wt.%,which can reduce the cost of binder by 20–30¥/t.

关键词： Metallurgical solid waste Iron-bearing dust Organic binder Liquid bridge Green pellet

基于2021版C-NCAP仪表板五星膝碰研究

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汽车科技 2024年第1期 61-69页

作者：李威叶勤亢胜利王洪明贺桥利东风汽车集团有限公司研发总院武汉430058

随着汽车工业的发展,汽车从“零死亡”向“零伤亡”再向“零事故”的终极目标不断前进,汽车的安全性尤其是碰撞安全越来越受到人们的关注。相较于2018版C-NCAP,2021版仪表板knee-mapping试验采用正面50%重叠移动渐进变形壁障碰撞试验(MP... 详细信息

随着汽车工业的发展,汽车从“零死亡”向“零伤亡”再向“零事故”的终极目标不断前进,汽车的安全性尤其是碰撞安全越来越受到人们的关注。相较于2018版C-NCAP,2021版仪表板knee-mapping试验采用正面50%重叠移动渐进变形壁障碰撞试验(MPDB)替代了正面40%重叠可变形壁障碰撞试验,同时引入了可变区域接触和集中力载荷的评分要求以及试验前提达成规则,评分要求越趋严格。本文基于对2021版C-NCAP膝碰评分规程解读,探索并提出达成五星膝碰的仪表板设计方法。

关键词： C-NCAP 仪表板五星膝碰

Epidemiology and region-specific risk factors for low Apgar scores in China:a nationwide study

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World Journal of Pediatrics 2022年第2期18卷 135-141页

作者： Yi-Wen Wang Yan Chen Yan-hong ming Jin-Wen Zhang Kun Sun Jun Zhang Yong-Jun Zhang Department of Neonatology Xinhua HospitalShanghai Jiao Tong University School of Medicine1665 Kongjiang RoadShanghai 200092China Department of Obstetrics and Gynecology Hospital of Obstetrics and GynecologyFudan UniversityShanghaiChina Shanghai Key Laboratory of Embryo Original Diseases The International Peace Maternity&Child Health HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Department of Pediatrics Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Ministry of Educaticn-Shanghai Key Laboratory of Children's Env ironmental Health Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina

Background Neonatal asphyxia is a serious public health *** study aimed to determine the epidemiology and region-specific risk factors for low Apgar scores,an important proxy for neonatal asphyxia,in China from 2015 to *** The China Labor and Delivery Survey was a multicenter cross-sectional study including 96 hospitals distributed in 24(out of 34)*** regression analysis was performed to examine the risk factors for a low Apgar score(<7).Correspondence analyses were performed among neonates with low Apgar scores to explore the relationship between risk factors and geographical *** population attributable risk percentage(PAR%)was calculated for each region-specific risk *** A total of 72,073 live births,including 320 births with low Apgar scores,were used for the analysis,giving a weighted rate of 3.9/1000 live *** was a substantial difference in the incidence of low Apgar scores by geographic region,from 2.3/1000 live births in East China to 10.9/1000 live births in Northeast *** and obstetric factors are the major region-specific risk *** Southwest China,hypertensive disorders in pregnancy were more important contributors,with PAR% being 74.47%;in North and Northwest China,pre-pregnancy underweight was a more significant factor,with PAR% of 62.92%;in East China,infants born between 0:00 *** 7:59 *** a key factor,with PAR% of 80.44%.Conclusion Strategies based on region-specific risk factors should be considered to reduce the burden of low Apgar scores in China.

关键词： Apgar score China Epidemiology Risk factor

基于AHP和未确知测度理论的旧桥耐久性评估

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内蒙古公路与运输 2024年第2期 20-26页

作者：姚杰邬晓光张彦飞宋嘉宇于鸿铭长安大学公路学院陕西西安710061 山西省公路局山西太原030006

钢筋混凝土桥梁耐久性影响因素多且复杂,并且有一定的不完整性和不确定性。针对以上问题,构建钢筋混凝土桥梁耐久性评估指标体系,结合层次分析法和未确知测度理论的优势,建立耐久性评估模型。首先该模型是在层次分析法建立层次化的指标... 详细信息

钢筋混凝土桥梁耐久性影响因素多且复杂,并且有一定的不完整性和不确定性。针对以上问题,构建钢筋混凝土桥梁耐久性评估指标体系,结合层次分析法和未确知测度理论的优势,建立耐久性评估模型。首先该模型是在层次分析法建立层次化的指标体系基础上将指标对混凝土桥梁耐久性的影响权重进行计算;其次辅以未确知测度理论中的测度函数对不确定信息进行处理并建立评价体系的指标测度矩阵;然后采用置信准则以及最小未确知测度距离判别法对桥梁耐久性等级进行确认;最后根据首阳桥的实际桥梁检测案例对模型进行验证。结果表明:基于层次分析法和未确知测度理论的桥梁耐久性评估模型对于首阳桥的耐久性评价等级为“较好状态”,该耐久性等级评价结果与实际桥梁状态相吻合。基于上述建立的耐久性评估体系可以为混凝土桥梁耐久性评估提供一定的参考。

关键词：层次分析法(AHP) 未确知测度理论桥梁耐久性混凝土桥梁