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Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin Zhang Guangyu Yang Lei Xiao Zhiyong Kan Jing guo qiang Li Wanqi Jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

Prediction and Research on Vegetable Price Based on Genetic Algorithm and Neural Network Model

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Asian Agricultural Research 2011年第5期3卷 148-150页

作者： guo qiang,LUO chang-shou,WEI Qing-feng Institute of Information on Science and Technology of Agriculture,Beijing Academy of Agriculture and Forestry Sciences,Beijing 100097,China

Considering the complexity of vegetables price forecast,the prediction model of vegetables price was set up by applying the neural network based on genetic algorithm and using the characteristics of genetic algorithm and neural *** mushrooms as an example,the parameters of the model are analyzed through *** the end,the results of genetic algorithm and BP neural network are *** results show that the absolute error of prediction data is in the scale of 10%;in the scope that the absolute error in the prediction data is in the scope of 20% and 15%.The accuracy of genetic algorithm based on neutral network is higher than the BP neutral network model,especially the absolute error of prediction data is within the scope of 20%.The accuracy of genetic algorithm based on neural network is obviously better than BP neural network model,which represents the favorable generalization capability of the model.

关键词： Genetic algorithm Neural network Vegetables price

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

Gamma-glutamyl transferase 5 overexpression in cerebrovascular endothelial cells improves brain pathology,cognition,and behavior in APP/PS1 mice

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Neural Regeneration Research 2025年第2期20卷 533-547页

作者： Yanli Zhang Tian Li Jie Miao Zhina Zhang Mingxuan Yang Zhuoran Wang Bo Yang Jiawei Zhang Haiting Li qiang Su Junhong guo Department of Neurology First Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Neurology Sixth Hospital of Shanxi Medical University(General Hospital of Tisco)TaiyuanShanxi ProvinceChina Department of Physiology Key Laboratory of Cellular PhysiologyMinistry of EducationShanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Hernia and Abdominal Wall Surgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Laboratory Medicine of Fenyang College Shanxi Medical UniversityFenyangShanxi ProvinceChina

In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial ***,the functional role of GGT5 in the development of Alzheimer’s disease remains *** study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer’s disease,as well as the underlying *** observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer’s disease(Aβ_(1-42)-treated hCMEC/D3 and bEnd.3 cells),as well as in the APP/PS1 mouse ***,injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive ***,increasing GGT5 expression in cerebrovascular endothelial cells reduced levels of both soluble and insoluble amyloid-βin the brains of APP/PS1 *** effect may be attributable to inhibition of the expression ofβ-site APP cleaving enzyme 1,which is mediated by nuclear factor-kappa *** findings demonstrate that GGT5 expression in cerebrovascular endothelial cells is inversely associated with Alzheimer’s disease pathogenesis,and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 *** findings suggest that GGT5 expression in cerebrovascular endothelial cells is a potential therapeutic target and biomarker for Alzheimer’s disease.

关键词： Alzheimer’s disease amyloid-β APP/PS1 mice cerebrovascular endothelial cells cognitive deficits gamma-glutamyl transferase 5 neurovascular unit nuclear factor‐kappa B synaptic plasticity β-site APP cleaving enzyme 1

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水深对塘堰湿地水力性能的影响

应用生态学报 2014年第11期25卷 3287-3295页

作者：郭长强董斌刘俊杰刘春果冯大鹏刘方平武汉大学水资源与水电工程科学国家重点实验室武汉430072 江西省灌溉试验中心站南昌330201

塘堰湿地因其良好的生态性能而被广泛用于水稻灌区的排水净化,由于湿地的水力性能及净化效果受到诸多因素影响,客观认识这些因素的作用机理有助于提高湿地设计和运行管理的质量.本文通过示踪剂试验探讨了不同水深(20、40、60 cm)对塘堰... 详细信息

塘堰湿地因其良好的生态性能而被广泛用于水稻灌区的排水净化,由于湿地的水力性能及净化效果受到诸多因素影响,客观认识这些因素的作用机理有助于提高湿地设计和运行管理的质量.本文通过示踪剂试验探讨了不同水深(20、40、60 cm)对塘堰湿地水力特性的影响.结果表明:随着湿地水深的减小,湿地的有效容积率从0.421增加到0.844,水力效率从0.281增加到0.604;在水深较小时(20和40 cm),湿地前半部分的有效容积率达到0.9以上,明显优于湿地整体情况,湿地前半部分的水流混合情况高,接近于完全混合流.通过对原始示踪曲线的标准化分析发现,矩分析参数与水力参数有较好的数值一致性,水力参数与不受尾部截断误差影响的矩指数之间具有良好的一致性.塘堰湿地水深较小时有利于提高湿地的水力性能,试验结果可为今后塘堰湿地的优化设计提供参考.

关键词：人工湿地水力性能示踪试验水力停留时间标准化

Tranylcypromine upregulates Sestrin 2 expression to ameliorate NLRP3-related noise-induced hearing loss

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Neural Regeneration Research 2025年第5期20卷 1483-1494页

作者： Xihang Chen Zhifeng Chen Menghua Li Weiwei guo Shuolong Yuan Liangwei Xu chang Lin Xi Shi Wei Chen Shiming Yang Senior Department of Otolaryngology Head and Neck Surgery Chinese PLA General HospitalChinese PLA Medical SchoolBeijingChina State Key Laboratory of Hearing and Balance Science BeijingChina National Clinical Research Center for Otolaryngologic Diseases BeijingChina Key Laboratory of Hearing Science Ministry of EducationBeijingChina Beijing Key Laboratory of Hearing Impairment Prevention and Treatment BeijingChina Department of Otorhinolaryngology Head and Neck Surgery The First Affiliated Hospital of Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Otolaryngology Head and Neck Surgery The 940th Hospital of Joint Logistics Support Force of Chinese PLALanzhouGansu ProvinceChina Key Laboratory of Tropical Biological Resources of Ministry of Education School of Pharmaceutical SciencesHainan UniversityHaikouHainan ProvinceChina Academician Workstation of Hainan University School of Pharmaceutical SciencesYazhou BaySanyaHainan ProvinceChina

Noise-induced hearing loss is the primary non-genetic factor contributing to auditory ***,there are currently no effective pharmacological interventions for patients with noise-induced hearing ***,we present evidence suggesting that the lysine-specific demethylase 1 inhibitor–tranylcypromine is an otoprotective agent that could be used to treat noise-induced hearing loss,and elucidate its underlying regulatory *** established a mouse model of permanent threshold shift hearing loss by exposing the mice to white broadband noise at a sound pressure level of 120 d B for 4 *** found that tranylcypromine treatment led to the upregulation of Sestrin2(SESN2)and activation of the autophagy markers light chain 3B and lysosome-associated membrane glycoprotein 1 in the cochleae of mice treated with *** noise exposure group treated with tranylcypromine showed significantly lower average auditory brainstem response hearing thresholds at click,4,8,and 16 k Hz frequencies compared with the noise exposure group treated with *** findings indicate that tranylcypromine treatment resulted in increased SESN2,light chain 3B,and lysosome-associated membrane glycoprotein 1 expression after noise exposure,leading to a reduction in levels of 4-hydroxynonenal and cleaved caspase-3,thereby reducing noise-induced hair cell ***,immunoblot analysis demonstrated that treatment with tranylcypromine upregulated SESN2 expression via the autophagy *** treatment also reduced the production of NOD-like receptor family pyrin domaincontaining 3(NLRP3)*** conclusion,our results showed that tranylcypromine treatment ameliorated cochlear inflammation by promoting the expression of SESN2,which induced autophagy,thereby restricting NLRP3-related inflammasome signaling,alleviating cochlear hair cell loss,and protecting hearing *** findings suggest that inhibiting lysine-specific demethylase 1 is a

关键词： 4-hydroxynonenal apoptosis autophagy cleaved caspase-3 inflammation NOD-like receptor family pyrin domain-containing 3(NLRP3) noise-induced hearing loss oxidative stress Sestrin2 tranylcypromine

Mechanical properties and microstructures of Mg-6Si alloys fabricated using the tungsten-inert-gas arc additive manufacturing

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China Foundry 2025年

作者： Peng-cheng Zhou guo-qiang You Jin-yu Feng Lei Wang Xiao Lin Bin Jiang College of Materials Science and Engineering Chongqing University National Engineering Research Center for Magnesium Alloys Chongqing University National Key Laboratory of Advanced Casting Technologies Chongqing University

Si-containing Mg alloys solidified at conventional rates often contain coarse and sharp Mg2Si phases,which can result in inferior material *** this study,Mg-6wt.%Si （Mg-6Si） alloy was prepared by wire arc additive manufacturing （WAAM）,employing the gas tungsten arc welding technique with rapid *** microstructures and mechanical properties of the WAAM alloy were investigated and compared with those of the as-cast samples produced using a metal *** results indicate that the WAAM Mg-6Si is harder and stronger than the as-cast *** microhardness of the WAAM Mg-6Si increases by 36.6%in comparison to that of as-cast Mg-6Si ***,the average tensile strengths at room temperature and 150°C increases by 63.4%and 21.3%,*** refines both the Mg2Si phase and the overall grains,resulting in a homogeneous morphology and improved mechanical *** granular Mg2Si phase,characterized by fine particles with a diffused distribution,shows a significant increase in *** acicular Mg2Si phase is distributed along the grain boundaries,and its concentration significantly *** average grain size of the Mg2Si phase is about 9.20μm,about 5 times *** refinement and distribution of the granular Mg2Si phase,as well as the reduction in the amount of needle-like Mg2Si particles,are the key factors for improving the mechanical properties of WAAM Mg-6Si alloy.

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人工湿地水力效率指标一致性与稳定性分析

灌溉排水学报 2014年第4期33卷 331-337页

作者：刘俊杰董斌郭长强 Larry Brown 武汉大学水资源与水电工程学科国家重点实验室武汉430072 俄亥俄州立大学哥伦布***

根据停留时间分布,选取4种水力效率指标(tm/tn、e(1-1/N)、tp/tn、Moment index),分别计算在不同水深、植被情况下其指标值,并研究其一致性;人为改变停留时间分布的有效长度后,重新计算水力效率指标值并排序,来研究其稳定性,同时用双边... 详细信息

根据停留时间分布,选取4种水力效率指标(tm/tn、e(1-1/N)、tp/tn、Moment index),分别计算在不同水深、植被情况下其指标值,并研究其一致性;人为改变停留时间分布的有效长度后,重新计算水力效率指标值并排序,来研究其稳定性,同时用双边T检验来检验指标的变化程度。结果表明,在一致性方面,由不同指标得到的湿地排序大体一致。仅在高水位和湿地植被全覆盖时,湿地排序局部出现了小变化。总体上水力效率指标一致性较好。有效长度改变后,在不同水深和植被情况下,湿地排序均基本不变。Moment index和tp/tn不变,tm/tn明显下降,e(1-1/N)变化不大。这表明:tm/tn受拖尾现象影响较大。指标的稳定性排序为Moment index>e(1-1/N)>tm/tn。

关键词：人工湿地水力效率停留时间分布矩分析排序

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FAST索网张拉过程模拟分析及误差控制

空间结构 2017年第3期23卷 36-40页

作者：罗平杰李亚东张国强姚昌荣西南交通大学土木工程学院四川成都610031 柳州欧维姆工程有限公司广西柳州545005

500m口径球面射电望远镜(FAST)采用柔性索网作为反射面的支承结构,柔性索网结构的张拉过程模拟分析对于张拉成形阶段具有重要的指导作用.基于非线性有限元理论,针对FAST索网的结构形式和施工方案,提出了索网张拉过程的模拟分析方法.通... 详细信息

500m口径球面射电望远镜(FAST)采用柔性索网作为反射面的支承结构,柔性索网结构的张拉过程模拟分析对于张拉成形阶段具有重要的指导作用.基于非线性有限元理论,针对FAST索网的结构形式和施工方案,提出了索网张拉过程的模拟分析方法.通过计算分析得到了索网在张拉过程中的位移和内力,计算结果验证了张拉方案的可行性.根据张拉过程中索网的内力变化,确定了FAST索网的误差调整方案.调索后,索力的实测值和计算值偏差在10%以内,说明调索效果较好.

关键词： FAST 索网结构张拉过程数值模拟误差