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The Spatial-Temporal Characteristics of Meteorological Disasters in the Southwest Region of Zhejiang Province during 1953-2022
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作者 qi zhang Yifan Wang +3 位作者 Zhidan Zhu Hongxia Shi Wenhao Yang Shujie Yuan 《Journal of Geoscience and Environment Protection》 2024年第3期16-27,共12页
Meteorological disasters are some of the most serious and costly natural disasters, which have larger effects on economic and social activity. Liuchun Lake is an ecotourism area in the southwest region of Zhejiang pro... Meteorological disasters are some of the most serious and costly natural disasters, which have larger effects on economic and social activity. Liuchun Lake is an ecotourism area in the southwest region of Zhejiang province, where also has experienced meteorological disasters including rainstorm and cold wave. Understanding the temporal-spatial characteristics of meteorological disasters is important for the local tourism and economic development. Based on the daily temperature and precipitation from 18 meteorological stations in the southwest of Zhejiang province during 1953-2022 and some statistical approaches, the temporal and spatial characteristics of meteorological disasters (Freezing, Rainstorm, Cold wave) are analyzed. The results indicate that 1) Rainstorm occurred frequently around the Liuchun lake, the frequency was about 8 times/a, it can also reach about 3 times/a in the other region. Freezing and cold wave (including strong cold wave and extremely cold wave) had the same spatial distribution as rainstorm, however, except for Liuchun lake, they occurred less than one time in the other regions;2) The trend of rainstorm had larger spatial difference, it increased in all the study area, but it increased more significantly around the study area than around Liuchun lake. Freezing was on the downtrend in the whole region, with 93.3% of the stations passed the 95% significant level. Cold wave also showed a declined trend, but it was insignificantly at most of the stations, only 33% of the stations passed the 90% significant level. Compared with cold wave, strong cold wave and extremely strong cold wave had weaker decline in all the regions. In general, from 1953 to 2022 rainstorm showed an increasing trend, it was the main meteorological disaster in the study area, cold wave displayed a decreasing trend, but it still occurred about 2 - 3 times/a in most regions. 展开更多
关键词 Southwest of Zhejiang Province RAINSTORM Cold Wave Spatial Distribution Trend Analysis
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基于主题讲座的“化学与社会进步”课程设计
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作者 蒋育澄 张琦 +1 位作者 魏灵灵 薛东 《大学化学》 CAS 2024年第4期251-254,共4页
本着“厚基础、宽口径、高素质、强能力、重创新”的本科人才培养理念和卓越教师的培养目标,结合陕西师范大学发展战略目标和“双一流”建设要求,作为一门面向全校师生开设的通识教育选修课程,为了更好地达成“化学与社会进步”课程的... 本着“厚基础、宽口径、高素质、强能力、重创新”的本科人才培养理念和卓越教师的培养目标,结合陕西师范大学发展战略目标和“双一流”建设要求,作为一门面向全校师生开设的通识教育选修课程,为了更好地达成“化学与社会进步”课程的目标任务,即“以适应社会经济发展需求和适应学生个体发展需求为导向,培养和造就卓越教师和专门人才”,同时为了破解具有不同学科背景和化学基础的学生同堂听课的困局以期打造高效课堂,本课程采用的教学策略是不使用现成的范本教材,而是定位于“在科普基础上的主题讲座”,通过一系列的教学设计充分发挥课堂教学的功能。 展开更多
关键词 通识教育选修课 化学与社会进步 课程设计 主题讲座
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超高强Ti-15Mo-2.7Nb-3Al-0.2Si钛合金的强化行为及模型
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作者 石晓辉 张琪 +3 位作者 荆镇 范智渊 刘江林 乔珺威 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第4期1136-1149,共14页
基于XRD、OM、SEM和TEM分析,研究超高强Ti-15Mo-2.7Nb-3Al-0.2Si钛合金的组织演变及强化行为。结果表明,位错强化和析出强化效应对该合金的屈服强度影响较大。冷轧+再结晶+冷轧+双时效组合工艺可获得1518 MPa的最高屈服强度,这主要归因... 基于XRD、OM、SEM和TEM分析,研究超高强Ti-15Mo-2.7Nb-3Al-0.2Si钛合金的组织演变及强化行为。结果表明,位错强化和析出强化效应对该合金的屈服强度影响较大。冷轧+再结晶+冷轧+双时效组合工艺可获得1518 MPa的最高屈服强度,这主要归因于显微组织中的高密度残存位错及密集而细小的次生α相。建立复合强化模型,其预测误差在16.6%以内。此外,研究发现次生α相体积分数的增加可以不断强化晶内区域,这使得沿晶断裂开始出现并逐渐占据整个断裂面。 展开更多
关键词 强化模型 超高强 强化行为 钛合金 Ti-15Mo-2.7Nb-3Al-0.2Si
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苝二酰亚胺共价有机框架超级还原剂用于高效光催化芳基卤化物还原反应
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作者 金昱丞 刘小琳 +9 位作者 曲琛 李长骏 王海龙 詹晓宁 曹昕怡 李晓锋 于宝秋 张琪 齐冬冬 姜建壮 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第2期171-183,共13页
自由基离子型分子光催化剂被证实是具有很强还原能力的可见光超级还原剂,它们在促进惰性的有机反应(例如将芳基卤化物还原为芳基自由基)方面具有突出的催化能力.然而,由于分子聚集严重地降低其催化活性,因而针对非均相超级还原剂的研究... 自由基离子型分子光催化剂被证实是具有很强还原能力的可见光超级还原剂,它们在促进惰性的有机反应(例如将芳基卤化物还原为芳基自由基)方面具有突出的催化能力.然而,由于分子聚集严重地降低其催化活性,因而针对非均相超级还原剂的研究较少.本文提出了一种新的方法来解决上述问题,通过溶剂热反应将具有连续光诱导电子转移机制的苝二亚胺超级还原剂(PDI)异质化为二维给体-受体(D-A)共价有机框架(COFs).即以N,N'-双(3-戊基)-2,5,8,11-四(4-甲酰基苯基)苝二酰亚胺(TFPDI)与1,3,6,8-四(4-氨基苯基)芘\(Py-TA)或2,3,6,7-四(4-氨基基苯基)四硫富瓦烯(TTF-TA)为原料,通过溶剂热反应分别制备了两种高晶态二维D-A型COF结构:USTB-21和USTB-22,并用于芳基氯化物、芳基溴化物和芳基碘化物的光催化还原反应.X射线衍射和理论模拟结果表明,USTB-21和USTB-22具有二维共价键连接的层状结构,分别呈现AA和AB的堆积方式.在各自最佳反应条件下,COFs显示出与均相催化剂相媲美的可见光催化性能,可高效地还原一系列芳基氯化物、芳基溴化物和芳基碘化物.其中,USTB-22在可见光驱动不同的芳香卤化物还原时,3 h内的转化率高达99%.瞬态吸收光谱结果表明,相比于均相催化剂(N,N'-双(2,6-二异丙基苯基)苝二酰亚胺),自由基阴离子激发态寿命是150 ps,USTB-21和USTB-22具有更长的激发态寿命,分别为210和260 ps.顺磁共振波谱测试结果证明,自由基阴离子光催化剂异质化成晶态D-A型COFs能够有效地促进电荷分离效率和延长激发态寿命.上述结果说明,USTB-22具有良好的光催化性能主要是因为其激发态寿命较长以及电荷分离效率较好.理论模拟结果表明,所制备的材料具有D-A型的电子结构.对COF的模型片段进行理论计算,揭示了各步反应路径中吉布斯自由能的变化,从而进一步阐明了光催化机理.在催化反应过程中,芳基卤化物还原途径可分为两个阶段:第一阶段为双光子能量输入和光驱电子转移,包括光子捕获和(TTF-PDI•−)^(*)产生以及光驱动电子转移到4-溴苯乙酮底物;第二阶段为能量输出,用于还原4-溴苯乙酮底物生成苯乙酮.综上所述,本文通过溶剂热反应将具有连续光诱导电子转移机制的苝二亚胺超级还原剂异质化为二维D-A型COFs结构.该结构在芳基氯化物、芳基溴化物和芳基碘化物等的光催化还原反应中,可很好地促进电子从光催化剂转移到反应物,进而显著提高光催化反应的活性和选择性;本研究对于未来设计新型自由基离子型高效光催化剂提供了新的思路. 展开更多
关键词 苝酰亚胺 共价有机骨架 光催化剂 均相 芳基卤化物的还原
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Neural stem cell-derived exosomes promote mitochondrial biogenesis and restore abnormal protein distribution in a mouse model of Alzheimer's disease 被引量:1
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作者 Bo Li Yujie Chen +10 位作者 Yan Zhou Xuanran Feng Guojun Gu Shuang Han Nianhao Cheng Yawen Sun Yiming zhang Jiahui Cheng qi zhang Wei zhang Jianhui Liu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1593-1601,共9页
Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheime... Mitochondrial dysfunction is a hallmark of Alzheimer’s disease.We previously showed that neural stem cell-derived extracellular vesicles improved mitochondrial function in the cortex of AP P/PS1 mice.Because Alzheimer’s disease affects the entire brain,further research is needed to elucidate alterations in mitochondrial metabolism in the brain as a whole.Here,we investigated the expression of several important mitochondrial biogenesis-related cytokines in multiple brain regions after treatment with neural stem cell-derived exosomes and used a combination of whole brain clearing,immunostaining,and lightsheet imaging to clarify their spatial distribution.Additionally,to clarify whether the sirtuin 1(SIRT1)-related pathway plays a regulatory role in neural stem cell-de rived exosomes interfering with mitochondrial functional changes,we generated a novel nervous system-SIRT1 conditional knoc kout AP P/PS1mouse model.Our findings demonstrate that neural stem cell-de rived exosomes significantly increase SIRT1 levels,enhance the production of mitochondrial biogenesis-related fa ctors,and inhibit astrocyte activation,but do not suppress amyloid-βproduction.Thus,neural stem cell-derived exosomes may be a useful therapeutic strategy for Alzheimer’s disease that activates the SIRT1-PGC1αsignaling pathway and increases NRF1 and COXIV synthesis to improve mitochondrial biogenesis.In addition,we showed that the spatial distribution of mitochondrial biogenesis-related factors is disrupted in Alzheimer’s disease,and that neural stem cell-derived exosome treatment can reverse this effect,indicating that neural stem cell-derived exosomes promote mitochondrial biogenesis. 展开更多
关键词 Alzheimer’s disease mitochondrial biogenesis neural stem cell-derived exosome SIRT1-PGC1α regional brain distribution whole brain clearing and imaging
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Copper Metabolism and Cuproptosis:Molecular Mechanisms and Therapeutic Perspectives in Neurodegenerative Diseases 被引量:1
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作者 Xiao-xia BAN Hao WAN +7 位作者 Xin-xing WAN Ya-ting TAN Xi-min HU Hong-xia BAN Xin-yu CHEN Kun HUANG qi zhang Kun XIONG 《Current Medical Science》 SCIE CAS 2024年第1期28-50,共23页
Copper is an essential trace element,and plays a vital role in numerous physiological processes within the human body.During normal metabolism,the human body maintains copper homeostasis.Copper deficiency or excess ca... Copper is an essential trace element,and plays a vital role in numerous physiological processes within the human body.During normal metabolism,the human body maintains copper homeostasis.Copper deficiency or excess can adversely affect cellular function.Therefore,copper homeostasis is stringently regulated.Recent studies suggest that copper can trigger a specific form of cell death,namely,cuproptosis,which is triggered by excessive levels of intracellular copper.Cuproptosis induces the aggregation of mitochondrial lipoylated proteins,and the loss of iron-sulfur cluster proteins.In neurodegenerative diseases,the pathogenesis and progression of neurological disorders are linked to copper homeostasis.This review summarizes the advances in copper homeostasis and cuproptosis in the nervous system and neurodegenerative diseases.This offers research perspectives that provide new insights into the targeted treatment of neurodegenerative diseases based on cuproptosis. 展开更多
关键词 cuproptosis copper metabolism copper homeostasis NEURODEGENERATION neurodegenerativedisease
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Heterointerface engineering of rhombic Rh nanosheets confined on MXene for efficient methanol oxidation
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作者 qi zhang Quanguo Jiang +6 位作者 Xiang Yang Chi zhang Jian zhang Lu Yang Haiyan He Guobing Ying Huajie Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期419-428,I0011,共11页
Although metallic rhodium(Rh)is regarded as a promising platinum-alternative anode catalyst of direct methanol fuel cell(DMFC),the conventional"particle-to-face"contact model between Rh and matrix largely li... Although metallic rhodium(Rh)is regarded as a promising platinum-alternative anode catalyst of direct methanol fuel cell(DMFC),the conventional"particle-to-face"contact model between Rh and matrix largely limits the overall electrocatalytic performance due to their insufficient cooperative effects.Herein,we report a controllable and robust heterointerface engineering strategy for the bottom-up fabrication of rhombic Rh nanosheets in situ confined on Ti_3C_(2)T_x MXene nanolamellas(Rh NS/MXene)via a convenient stereoassembly process.This unique design concept gives the resulting 2D/2D Rh NS/MXene heterostructure intriguing textural features,including large accessible surface areas,strong"face-toface"interfacial interactions,homogeneous Rh nanosheet distribution,ameliorative electronic structure,and high electronic conductivity.As a consequence,the as-prepared Rh NS/MXene nanoarchitectures exhibit exceptional electrocatalytic methanol oxidation properties in terms of a large electrochemically active surface area of 126.2 m~2 g_(Rh)~(-1),a high mass activity of 1056.9 mA mg_(Rh)-~1,and a long service life,which significantly outperform those of conventional particle-shaped Rh catalysts supported by carbon black,carbon nanotubes,reduced graphene oxide,and MXene matrixes as well as the commercial Pt nanoparticle/carbon black and Pd nanoparticle/carbon black catalysts with the same noble metal loading amount.Density functional theory calculations further demonstrate that the direct electronic interaction at the well-contacted 2D/2D heterointerfaces effectively enhances the adsorption energy of Rh nanosheets and induces a left shift of the d-band center,thereby making the Rh NS/MXene configuration suffer less from CO poisoning.This work highlights the importance of rational heterointerface design in the construction of advanced noble metal/MXene electrocatalysts,which may provide new avenues for developing the next-generation DMFC devices. 展开更多
关键词 Rhodium nanosheet Ti_(3)C_(2)T_(x)MXene HETEROINTERFACE ELECTROCATALYST Fuel cell
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Enabling an Inorganic-Rich Interface via Cationic Surfactant for High-Performance Lithium Metal Batteries
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作者 Zejun Sun Jinlin Yang +18 位作者 Hongfei Xu Chonglai Jiang Yuxiang Niu Xu Lian Yuan Liu Ruiqi Su Dayu Liu Yu Long Meng Wang Jingyu Mao Haotian Yang Baihua Cui Yukun Xiao Ganwen Chen qi zhang Zhenxiang Xing Jisheng Pan Gang Wu Wei Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期1-17,共17页
An anion-rich electric double layer(EDL)region is favorable for fabricating an inorganic-rich solid-electrolyte interphase(SEI)towards stable lithium metal anode in ester electrolyte.Herein,cetyltrimethylammonium brom... An anion-rich electric double layer(EDL)region is favorable for fabricating an inorganic-rich solid-electrolyte interphase(SEI)towards stable lithium metal anode in ester electrolyte.Herein,cetyltrimethylammonium bromide(CTAB),a cationic surfactant,is adopted to draw more anions into EDL by ionic interactions that shield the repelling force on anions during lithium plating.In situ electrochemical surface-enhanced Raman spectroscopy results combined with molecular dynamics simulations validate the enrichment of NO_(3)^(−)/FSI−anions in the EDL region due to the positively charged CTA^(+).In-depth analysis of SEI structure by X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry results confirmed the formation of the inorganic-rich SEI,which helps improve the kinetics of Li^(+)transfer,lower the charge transfer activation energy,and homogenize Li deposition.As a result,the Li||Li symmetric cell in the designed electrolyte displays a prolongated cycling time from 500 to 1300 h compared to that in the blank electrolyte at 0.5 mA cm^(-2) with a capacity of 1 mAh cm^(-2).Moreover,Li||LiFePO_(4) and Li||LiCoO_(2) with a high cathode mass loading of>10 mg cm^(-2) can be stably cycled over 180 cycles. 展开更多
关键词 Cationic surfactant Lithium nitrate additive Solid-electrolyte interphase Electric double layer Lithium metal batteries
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Host-induced silencing of MpPar6 confers Myzus persicae resistance in transgenic rape plants
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作者 qi zhang Wenqin Zhan +3 位作者 Chao Li Ling Chang Yi Dong Jiang zhang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期187-194,共8页
Plant-mediated RNA interference(RNAi)has emerged as a promising technology for insect control.The green peach aphid,Myzus persicae,feeds on over 400 species of host plants.Brassica napus(rape)is the second most import... Plant-mediated RNA interference(RNAi)has emerged as a promising technology for insect control.The green peach aphid,Myzus persicae,feeds on over 400 species of host plants.Brassica napus(rape)is the second most important oilseed crop worldwide.Myzus persicae is highly reproductive and causes severe damage to the rape plants due to its quite flexible life cycle.In this study,we tested the RNAi effects of transgenic rape plants on M.persicae.By in vitro feeding M.persicae with artificial diets containing double-stranded RNAs(dsRNAs)targeting seven aphid genes,we identified a new gene encoding the partitioning-defective protein 6(Par6)as the most potent RNAi target.Tissue-and stage-expression analysis of Par6 suggested this gene is highly expressed in the embryo and adult stage of M.persicae.We next generated transgenic rape plants expressing ds Par6 by Agrobacteriummediated transformation and obtained nine independent transgenic lines.Compared to wild-type control plants,transgenic rape lines expressing ds Par6 showed strong resistance to M.persicae.Feeding assays revealed that feeding transgenic rape plants to M.persicae significantly decreased MpPar6 expression and survival rate and impaired fecundity.Furthermore,we showed that the resistance levels to M.persicae are positively correlated with ds Par6 expression levels in transgenic rape plants.Our study demonstrates that transgenic rape plants expressing ds Par6 are efficiently protected from M.persicae.Interfering with the genes involved in embryo development could be the effective RNAi targets for controlling aphids and potentially other insect pests. 展开更多
关键词 oilseed rape pest control APHID double-stranded RNA RNA interference
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Contact Stress Reliability Analysis Model for Cylindrical Gear with Circular Arc Tooth Trace Based on an Improved Metamodel
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作者 qi zhang Zhixin Chen +5 位作者 Yang Wu Guoqi Xiang Guang Wen Xuegang zhang Yongchun Xie Guangchun Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期593-619,共27页
Although there is currently no unified standard theoretical formula for calculating the contact stress of cylindrical gears with a circular arc tooth trace(referred to as CATT gear),a mathematical model for determinin... Although there is currently no unified standard theoretical formula for calculating the contact stress of cylindrical gears with a circular arc tooth trace(referred to as CATT gear),a mathematical model for determining the contact stress of CATT gear is essential for studying how parameters affect its contact stress and building the contact stress limit state equation for contact stress reliability analysis.In this study,a mathematical relationship between design parameters and contact stress is formulated using the KrigingMetamodel.To enhance the model’s accuracy,we propose a new hybrid algorithm that merges the genetic algorithm with the Quantum Particle Swarm optimization algorithm,leveraging the strengths of each.Additionally,the“parental inheritance+self-learning”optimization model is used to fine-tune the KrigingMetamodel’s parameters.Following this,amathematicalmodel for calculating the contact stress of Variable Hyperbolic Circular-Arc-Tooth-Trace(VH-CATT)gears using the optimized Kriging model was developed.We then examined how different gear parameters affect the VH-CATT gears’contact stress.Our simulation results show:(1)Improvements in R2,RMSE,and RMAE.R2 rose from0.9852 to 0.9974(a 1.22%increase),nearing 1,suggesting the optimized Kriging Metamodel’s global error is minimized.Meanwhile,RMSE dropped from3.9210 to 1.6492,a decline of 57.94%.The global error of the GA-IQPSO-Kriging algorithm was also reduced,with RMAE decreasing by 58.69%from 0.1823 to 0.0753,showing the algorithm’s enhanced precision.In a comparison of ten experimental groups selected randomly,the GA-IQPSO-Kriging and FEM-based contact analysis methods were used to measure contact stress.Results revealed a maximum error of 12.11667 MPA,which represents 2.85%of the real value.(2)Several factors,including the pressure angle,tooth width,modulus,and tooth line radius,are inversely related to contact stress.The descending order of their impact on the contact stress is:tooth line radius>modulus>pressure angle>tooth width.(3)Complex interactions are noted among various parameters.Specifically,when the tooth line radius interacts with parameters such as pressure angle,tooth width,and modulus,the resulting stress contour is nonlinear,showcasing amultifaceted contour plane.However,when tooth width,modulus,and pressure angle interact,the stress contour is nearly linear,and the contour plane is simpler,indicating a weaker coupling among these factors. 展开更多
关键词 CATT gear contact stress finite element method METAMODEL hybrid algorithm influencing factors
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Experimental study on the influences of cutter geometry and material on scraper wear during shield TBM tunnelling in abrasive sandy ground
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作者 Shaohui Tang Xiaoping zhang +3 位作者 Quansheng Liu qi zhang Xinfang Li Haojie Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期410-425,共16页
When shield TBM tunnelling in abrasive sandy ground,the rational design of cutter parameters is critical to reduce tool wear and improve tunnelling efficiency.However,the influence mechanism of cutter parameters on sc... When shield TBM tunnelling in abrasive sandy ground,the rational design of cutter parameters is critical to reduce tool wear and improve tunnelling efficiency.However,the influence mechanism of cutter parameters on scraper wear remains unclear due to the lack of a reliable test method.Geometry and material optimisation are often based on subjective experience,which is unfavourable for improving scraper geological adaptability.In the present study,the newly developed WHU-SAT soil abrasion test was used to evaluate the variation in scraper wear with cutter geometry,material and hardness.The influence mechanism of cutter parameters on scraper wear has been revealed according to the scratch characteristics of the scraper surface.Cutter geometry and material parameters have been optimised to reduce scraper wear.The results indicate that the variation in scraper wear with cutter geometry is related to the cutting resistance,frictional resistance and stress distribution.An appropriate increase in the front angle(or back angle)reduces the cutting resistance(or frictional resistance),while an excessive increase in the front angle(or back angle)reduces the edge angle and causes stress concentration.The optimal front angle,back angle and edge angle for quartz sand samples areα=25°,β=10°andγ=55°,respectively.The wear resistance of the modelled scrapers made of different metal materials is related to the chemical elements and microstructure.The wear resistances of the modelled scrapers made of 45#,06Cr19Ni10,42CrMo4 and 40CrNiMoA are 0.569,0.661,0.691 and 0.728 times those made of WC-Co,respectively.When the alloy hardness is less than 47 HRC(or greater than 58 HRC),scraper wear decreases slowly with increasing alloy hardness as the scratch depth of the particle asperity on the metal surface stabilizes at a high(or low)level.However,when the alloy hardness is between 47 HRC and 58 HRC,scraper wear decreases rapidly with increasing alloy hardness as the scratch depth transitions from high to low levels.The sensitive hardness interval and recommended hardness interval for quartz sand are[47,58]and[58,62],respectively.The present study provides a reference for optimising scraper parameters and improving cutterhead adaptability in abrasive sandy ground tunnelling. 展开更多
关键词 Shield TBM Scraper wear Cutter shape Metal material Alloy hardness
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Prediction of high-embankment settlement combining joint denoising technique and enhanced GWO-v-SVR method
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作者 qi zhang qian Su +2 位作者 Zongyu zhang Zhixing Deng De Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期317-332,共16页
Reliable long-term settlement prediction of a high embankment relates to mountain infrastructure safety.This study developed a novel hybrid model(NHM)that combines a joint denoising technique with an enhanced gray wol... Reliable long-term settlement prediction of a high embankment relates to mountain infrastructure safety.This study developed a novel hybrid model(NHM)that combines a joint denoising technique with an enhanced gray wolf optimizer(EGWO)-n-support vector regression(n-SVR)method.High-embankment field measurements were preprocessed using the joint denoising technique,which in-cludes complete ensemble empirical mode decomposition,singular value decomposition,and wavelet packet transform.Furthermore,high-embankment settlements were predicted using the EGWO-n-SVR method.In this method,the standard gray wolf optimizer(GWO)was improved to obtain the EGWO to better tune the n-SVR model hyperparameters.The proposed NHM was then tested in two case studies.Finally,the influences of the data division ratio and kernel function on the EGWO-n-SVR forecasting performance and prediction efficiency were investigated.The results indicate that the NHM suppresses noise and restores details in high-embankment field measurements.Simultaneously,the NHM out-performs other alternative prediction methods in prediction accuracy and robustness.This demonstrates that the proposed NHM is effective in predicting high-embankment settlements with noisy field mea-surements.Moreover,the appropriate data division ratio and kernel function for EGWO-n-SVR are 7:3 and radial basis function,respectively. 展开更多
关键词 High embankment Settlement prediction Joint denoising technique Enhanced gray wolf optimizer Support vector regression
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Survey on performance of vertical slot and nature-like fishways at Angu hydropower station, Southwest China
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作者 Jun-jian Sun Jia-yue Shi +2 位作者 qi zhang Xiao-tao Shi Jun-jun Tan 《Water Science and Engineering》 EI CAS CSCD 2024年第1期83-91,共9页
To restore dam-blocked natural fish migratory passages,a growing number of artificial fishways have been built in water conservancy and hydropower projects in China.The Angu hydropower station involved diverse importa... To restore dam-blocked natural fish migratory passages,a growing number of artificial fishways have been built in water conservancy and hydropower projects in China.The Angu hydropower station involved diverse important fish habitats in the lower reaches of the Daduhe River in Southwest China.Therefore,a vertical slot fishway(VSF)and a nature-like fishway(NLF)were built near the backwater area of the reservoir to connect the upstream and downstream habitats.Hydrodynamic and aquatic ecological surveys were conducted after the completion of the project to estimate the fish passing effect of the two fishways.The results indicated that both fishways were in effective operation and could maintain the desired hydrodynamic conditions and be used by several local fish species.During the survey,149 fish from 15 species and 111 fish from 17 species were captured by the traps in the VSF and NLF,respectively,while 1263 fish from 27 species were found in the downstream area.Some species captured in the VSF were not found in the NLF,and vice versa,which implied the different preferences of fish.Meanwhile,3789 signals including 2099 upward ones and 1690 downward ones were monitored with an ultrasonic fish detector at the inlet of the VSF.These findings revealed the characteristics of fish species observed in and near the fishways and provided valuable insights into the different fish passing capabilities of VSFandNLF. 展开更多
关键词 Vertical slot fishway Nature-like fishway Aguatic ecological survey Fishwaymonitoring Statistical analysis
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Dynamic transcriptome profiles and novel markers in bovine spermatogenesis revealed by single-cell sequencing
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作者 Yuan Gao Fuxia Bai +4 位作者 qi zhang Xiaoya An Zhaofei Wang Chuzhao Lei Ruihua Dang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第7期2362-2378,共17页
Testicular development is an important biological process in male and requires interaction between the male germ cells and somatic cells.However,the mechanisms of testicular development in livestock,particularly in ca... Testicular development is an important biological process in male and requires interaction between the male germ cells and somatic cells.However,the mechanisms of testicular development in livestock,particularly in cattle,are poorly understood.Furthermore,cellular heterogeneity hinders the profiling of different cell types at different developmental stages.In this study,we first performed a single-cell transcriptomic study of the bovine testis development during puberty by using 10×genomics single-cell RNA sequencing(scRNA-seq).By collecting the scRNA-seq data from 11,083 cells from prepubertal and pubertal bovine testes,a high-resolution scRNA-seq atlas was described,identifying 9 somatic and 13 spermatogenic clusters.We also distinguished several stage-specific marker genes for bovine germ cells and somatic cells,such as GRAF2 and MORC1 for SSC(spermatogonial stem cells),HJURP and TCF19 for differentiating spermatogonia,ARSE for immature Sertoli,CLEC12B for mature Sertoli,LOC112441470 for Leydig.In conclusion,we have examined the transcription levels and constructed the single-cell developmental maps of germ cells and somatic cells during testicular development in Angus cattle.The datasets provided new insights into spermatogenesis and testicular somatic cell development in cattle. 展开更多
关键词 scRNA-seq CATTLE SPERMATOGENESIS testis development
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Expert consensus on difficulty assessment of endodontic therapy
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作者 Dingming Huang Xiaoyan Wang +33 位作者 Jingping Liang Junqi Ling Zhuan Bian qing Yu Benxiang Hou Xinmei Chen Jiyao Li Ling Ye Lei Cheng Xin Xu Tao Hu Hongkun Wu Bin Guo qin Su Zhi Chen Lihong qiu Wenxia Chen Xi Wei Zhengwei Huang Jinhua Yu Zhengmei Lin qi zhang Deqin Yang Jin Zhao Shuang Pan Jian Yang Jiayuan Wu Yihuai Pan Xiaoli Xie Shuli Deng Xiaojing Huang Lan zhang Lin Yue Xuedong Zhou 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第1期15-25,共11页
Endodontic diseases are a kind of chronic infectious oral disease. Common endodontic treatment concepts are based on the removal of inflamed or necrotic pulp tissue and the replacement by gutta-percha. However, it is ... Endodontic diseases are a kind of chronic infectious oral disease. Common endodontic treatment concepts are based on the removal of inflamed or necrotic pulp tissue and the replacement by gutta-percha. However, it is very essential for endodontic treatment to debride the root canal system and prevent the root canal system from bacterial reinfection after root canal therapy(RCT). Recent research, encompassing bacterial etiology and advanced imaging techniques, contributes to our understanding of the root canal system’s anatomy intricacies and the technique sensitivity of RCT. Success in RCT hinges on factors like patients, infection severity, root canal anatomy, and treatment techniques. Therefore, improving disease management is a key issue to combat endodontic diseases and cure periapical lesions. The clinical difficulty assessment system of RCT is established based on patient conditions, tooth conditions, root canal configuration, and root canal needing retreatment, and emphasizes pre-treatment risk assessment for optimal outcomes. The findings suggest that the presence of risk factors may correlate with the challenge of achieving the high standard required for RCT. These insights contribute not only to improve education but also aid practitioners in treatment planning and referral decision-making within the field of endodontics. 展开更多
关键词 ANATOMY DIFFICULTY TREATMENT
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High-pressure study on calcium azide(Ca(N_(3))_(2)):Bending of azide ions stabilizes the structure
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作者 武晓鑫 王颖健 +7 位作者 李思琪 吕俊呈 王婧姝 杨丽华 张旗 刘艳清 张俊凯 贾洪声 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期542-548,共7页
The high-pressure structure and elastic properties of calcium azide(Ca(N_(3))_(2))were investigated using in-situ highpressure x-ray diffraction and Raman scattering up to 54 GPa and 19 GPa,respectively.The compressib... The high-pressure structure and elastic properties of calcium azide(Ca(N_(3))_(2))were investigated using in-situ highpressure x-ray diffraction and Raman scattering up to 54 GPa and 19 GPa,respectively.The compressibility of Ca(N_(3))_(2)changed as the pressure increased,and no phase transition occurred within the pressure from ambient pressure up to 54 GPa.The measured zero-pressure bulk modulus of Ca(N_(3))_(2)is higher than that of other alkali metal azides,due to differences in the ionic character of their metal-azide bonds.Using CASTEP,all vibration modes of Ca(N_(3))_(2)were accurately identified in the vibrational spectrum at ambient pressure.In the high-pressure vibration study,several external modes(ext.)and internal bending modes(ν_(2))of azide anions(N_(3)^(-))softened up to~7 GPa and then hardened beyond that pressure.This evidence is consistent with the variation observed in the F_(E)–f_(E)data analyzed from the XRD result,where the slope of the curve changes at 7.1 GPa.The main behaviors under pressure are the alternating compression,rotation,and bending of N_(3)^(-)ions.The bending behavior makes the structure of Ca(N_(3))_(2)more stable under pressure. 展开更多
关键词 high pressure calcium azide azide anions
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Silvestrol alleviates glioblastoma progression through ERK pathway modulation and MANBA and NRG-1 expression
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作者 LAN ZHOU qi zhang +1 位作者 BO TIAN FENG YANG 《BIOCELL》 SCIE 2024年第7期1081-1093,共13页
Background:Glioblastoma,a notably malignant tumor within the central nervous system,is distinguished by its aggressive behavior.Silvestrol,a robust inhibitor of the RNA helicase eukaryotic initiation factor 4A(eIF4A),... Background:Glioblastoma,a notably malignant tumor within the central nervous system,is distinguished by its aggressive behavior.Silvestrol,a robust inhibitor of the RNA helicase eukaryotic initiation factor 4A(eIF4A),has shown significant potential as an anticancer compound.Yet,the impact of silvestrol on glioblastoma,especially its molecular mechanisms,has not been fully elucidated.Methods:This investigation employed a variety of in vitro assays,such as cell counting kit-8(CCK-8),clonogenic,5-ethynyl-2′-deoxyuridine(EDU),wound healing,and flow cytometry,to evaluate cell cycle progression,apoptosis,cell viability,and migration.Western blot analysis was also performed to study the apoptosis and extracellular regulated kinase(ERK)pathways.After the ERK pathway was inhibited,differentially expressed genes(DEGs)in U87 cells were identified,followed by an analysis of target genes using the gene expression profiling interactive analysis(GEPIA)database.Results:Silvestrol significantly suppressed the proliferation,migration,and colony formation of glioma cells.It caused cell cycle arrest and enhanced apoptosis in these cells.Additionally,silvestrol stimulated the ERK pathway,with these effects being reversible by an ERK phosphorylation inhibitor.Transcriptome combined with GEPIA,GSCA,UALCAN,TIMER database screened 4 potential drug targets of silvestrol:chromosome 1 open reading frame 226(C1ORF226),mannosidase beta A(MANBA),IQ motif and Sec7 domain 2(IQSEC2),neuregulin 1(NRG-1).Among them,C1ORF226 was lower risk gene while MANBA,IQSEC2,and NRG-1 were high-risk genes.Furthermore,silvestrol notably reduced MANBA mRNA levels,which could be reversed by inhibiting ERK phosphorylation.Furthermore,silvestrol markedly decreased NRG-1 protein levels,with an additional reduction observed when the ERK pathway was blocked.Conclusion:Silvestrol’s anti-glioma effects are primarily due to the suppression of MANBA expression via the ERK pathway and possibly by hindering the translation of NRG-1 protein,thus reducing its expression.The downregulation of MANBA and NRG-1 proteins may be crucial in hindering glioma development and progression.These results highlight the intricate relationship between the ERK pathway and gene expression regulation in silvestrol’s therapeutic effectiveness against glioma. 展开更多
关键词 GLIOBLASTOMA Silvestrol ERK pathway MANBA NRG-1
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Unsupervised Multi-Expert Learning Model for Underwater Image Enhancement
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作者 Hongmin Liu qi zhang +2 位作者 Yufan Hu Hui Zeng Bin Fan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期708-722,共15页
Underwater image enhancement aims to restore a clean appearance and thus improves the quality of underwater degraded images.Current methods feed the whole image directly into the model for enhancement.However,they ign... Underwater image enhancement aims to restore a clean appearance and thus improves the quality of underwater degraded images.Current methods feed the whole image directly into the model for enhancement.However,they ignored that the R,G and B channels of underwater degraded images present varied degrees of degradation,due to the selective absorption for the light.To address this issue,we propose an unsupervised multi-expert learning model by considering the enhancement of each color channel.Specifically,an unsupervised architecture based on generative adversarial network is employed to alleviate the need for paired underwater images.Based on this,we design a generator,including a multi-expert encoder,a feature fusion module and a feature fusion-guided decoder,to generate the clear underwater image.Accordingly,a multi-expert discriminator is proposed to verify the authenticity of the R,G and B channels,respectively.In addition,content perceptual loss and edge loss are introduced into the loss function to further improve the content and details of the enhanced images.Extensive experiments on public datasets demonstrate that our method achieves more pleasing results in vision quality.Various metrics(PSNR,SSIM,UIQM and UCIQE) evaluated on our enhanced images have been improved obviously. 展开更多
关键词 Multi-expert learning underwater image enhancement unsupervised learning
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Enhanced Spin–Orbit Torques in Graphene by Pt Adatoms Decoration
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作者 王怡飞 张其 +7 位作者 徐海茗 郭玺 常宇晗 张健荣 和孝东 左亚路 崔宝山 席力 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第6期141-147,共7页
Graphene(Gr)with widely acclaimed characteristics,such as exceptionally long spin diffusion length at room temperature,provides an outstanding platform for spintronics.However,its inherent weak spin–orbit coupling(SO... Graphene(Gr)with widely acclaimed characteristics,such as exceptionally long spin diffusion length at room temperature,provides an outstanding platform for spintronics.However,its inherent weak spin–orbit coupling(SOC)has limited its efficiency for generating the spin currents in order to control the magnetization switching process for applications in spintronics memories.Following the theoretical prediction on the enhancement of SOC in Gr by heavy atoms adsorption,here we experimentally observe a sizeable spin–orbit torques(SOTs)in Gr by the decoration of its surface with Pt adatoms in Gr/Pt(t Pt)/Fe Ni trilayers with the optimal damping-like SOT efficiency around 0.55 by 0.6-nm-thick Pt layer adsorption.The value is nearly four times larger than that of the Pt/Fe Ni sample without Gr and nearly twice the value of the Gr/Fe Ni sample without Pt adsorption.The efficiency of the enhanced SOT in Gr by Pt adatoms is also demonstrated by the field-free SOT magnetization switching process with a relatively low critical current density around 5.4 MA/cm^(2)in Gr/Pt/Fe Ni trilayers with the in-plane magnetic anisotropy.These findings pave the way for Gr spintronics applications,offering solutions for future low power consumption memories. 展开更多
关键词 MAGNETIZATION exceptional GENERATING
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Misdiagnosed Meckel's diverticulum with internal hernia mimicking appendicitis:A case report
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作者 qi zhang Xiu-Juan Xu +1 位作者 Jun Ma Ya-Ming zhang 《World Journal of Clinical Cases》 SCIE 2024年第20期4391-4396,共6页
BACKGROUND Meckel's diverticulum is a common congenital anomaly of the gastrointestinal tract,with a higher incidence rate in children under 7 years old.The condition is characteristically asymptomatic but may bec... BACKGROUND Meckel's diverticulum is a common congenital anomaly of the gastrointestinal tract,with a higher incidence rate in children under 7 years old.The condition is characteristically asymptomatic but may become a clinical concern when complications such as intestinal obstruction,bleeding,perforation,or diverticulitis precipitate acute abdominal presentations.CASE SUMMARY This report describes the case of a middle-aged man initially suspected of having acute appendicitis,which rapidly progressed to acute peritonitis with concomitant intestinal obstruction observed during preoperative assessment.Surgical exploration confirmed the diagnosis of Meckel's diverticulum-induced internal hernia,accompanied by intestinal obstruction and necrosis.In addition,the hernial ring base exhibited entrapment resembling a surgical knot.CONCLUSION Meckel's diverticulum is a rare cause of small bowel obstruction in adults,and it should be considered in a differential diagnosis. 展开更多
关键词 Meckel's diverticulum Internal hernia Intestinal necrosis PERITONITIS Case report
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