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High-Temperature Stability of Mg-1Al-12Y Alloy Containing LPSO Phase and Mechanism of Its Portevin-Le Chatelier(PLC)Effect

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 982-998页

作者： qian-long Ren Shuai Yuan Shi-Yu Luan Jin-Hui Wang Xiao-Wei Li Xiao-Yu Liu Qinghai Provincial Key Laboratory of New Light Alloys Qinghai Provincial Engineering Research Center of High Performance Light Metal Alloys and FormingQinghai UniversityXining810016China School of Materials Science and Engineering Shenyang University of TechnologyShenyang110870China

In this study,the high-temperature stability and the generation mechanism of the Portevin-Le Chatelier(PLC)effect in solid-solution Mg-1Al-12Y alloy with different heat treatment processes were investigated by adjusting the content of long-period stacking ordered(LPSO)*** was found that the content of LPSO phases in the alloys differed the most after heat treatment at 530℃for 16 h and 24 h,with values of 13.56%and 3.93%***,high-temperature tensile experiments were conducted on these two alloys at temperatures of 150℃,200℃,250℃,and 300℃.The results showed that both alloys exhibited the PLC effect at temperatures ranging from 150 to 250℃.However,at a temperature 300℃,only the alloy with a greater concentration of LPSO phases exhibited the PLC effect,whereas the alloy with a lower proportion of LPSO phases did not exhibit this ***,both alloys exhibited remarkable high-temperature stability,with the alloy containing a greater percentage of LPSO phases also demonstrating superior *** underlying mechanism for this phenomenon lies in the exceptional high-temperature stability exhibited by the second phase within the ***,the LPSO phase effectively obstructs the movement of dislocations,and it also undergoing kinking to facilitate plastic deformation of the *** results indicate that the PLC effect can be suppressed by reducing dislocation pile-up at grain boundaries,which leads to a decrease in alloy plasticity but an increase in *** presence of the PLC effect in the WA121 alloy is attributed to the abundant dispersed second phase within the alloy,which initially hinders the movement of dislocations,leading to an increase in stress,and subsequently releases the dislocations,allowing them to continue their movement and thereby reducing in stress.

关键词： Magnesium alloy long-period stacking ordered(LPSO)phase Portevin-Le Chatelier effect High temperature

Towards Lessening Learners’Aversive Emotions and Promoting Their Mental Health:Developing and Validating a Measurement of English Speaking Demotivation in the Chinese EFL Context

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International Journal of Mental Health Promotion 2024年第2期26卷 161-175页

作者： Chili Li Xinxin Zhao Ziwen Pan Ting Yi long qian School of Foreign Languages Hubei University of TechnologyWuhan430068China Faculty of Education The University of Hong KongHong Kong999077China School of Foreign Languages Henan UniversityKaifeng450046China Research Institute of International Chinese Language Education Beijing Language and Culture UniversityBeijing100083China Faculty of Humanities The Hong Kong Polytechnic UniversityHong Kong100872China School of Humanities Wuhan University of Engineering ScienceWuhan430200China

While a plethora of studies has been conducted to explore demotivation and its impact on mental health in second language(L2)education,scanty research focuses on demotivation in L2 speaking ***,little research explores the measures to quantify L2 speaking *** present two-phase study attempts to develop and validate an English Speaking Demotivation Scale(ESDS).To this end,an independent sample of 207 Chinese tertiary learners of English as a Foreign Language(EFL)participated in the development phase,and another group of 188 Chinese EFL learners was recruited for the validation of the *** Factor Analysis(EFA)and Confirmatory Factor Analysis(CFA)were employed to determine the factor structure of the *** EFA results revealed a six-factor solution with Teacher-related Factors in Learning Spoken English(TFLSE),Interest and Valence in Learning Spoken English(IVLSE),Self-efficacy in Learning Spoken English(SELSE),Negative Peer Influence in Learning Spoken English(NPILSE),Undesirable Environment for Learning Spoken English(UELSE),and Negative Influence of Assessment and Learning Materials in speaking class(NIALM).In the validation phase,Confirmatory Factor Analysis(CFA)was performed to validate the internal structure of the *** CFA results showed that the model fits the data ***,the ESDS is a robust and trustworthy psychometric tool that could be utilized to examine L2 speaking *** for diminishing EFL learners’demotivation,lessening their aversive emotions and promoting their mental health are also discussed.

关键词： Demotivation for learning English speaking ESDS scale development and validation Chinese EFL learners mental health

Functional predictability of universal gene circuits in diverse microbial hosts

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Quantitative Biology 2024年第2期12卷 129-140页

作者： Chenrui Qin Tong Xu Xuejin Zhao Yeqing Zong Haoqian MZhang Chunbo Lou Qi Ouyang long qian Peking-Tsinghua Joint Center for Life Sciences Peking UniversityBeijingChina CAS Key Laboratory of Microbial Physiological and Metabolic Engineering Institute of MicrobiologyChinese Academy of SciencesBeijingChina Bluepha Co. LtdBeijingChina Center for Cell and Gene Circuit Design CAS Key Laboratory of Quantitative Engineering BiologyGuangdong Provincial Key Laboratory of Synthetic GenomicsShenzhen Key Laboratory of Synthetic GenomicsShenzhen Institute of Synthetic BiologyShenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenChina Center for Quantitative Biology Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijingChina

Although the principles of synthetic biology were initially established in model bacteria,microbial producers,extremophiles and gut microbes have now emerged as valuable prokaryotic chassis for biological *** the host range in which designed circuits can function reliably and predictably presents a major challenge for the concept of synthetic biology to *** this work,we systematically characterized the cross-species universality of two transcriptional regulatory modules—the T7 RNA polymerase activator module and the repressors module—in three non-model *** found striking linear relationships in circuit activities among different organisms for both *** model fitting revealed host non-specific parameters defining the universality of both ***,a genetic NOT gate and a band-pass filter circuit were constructed from these modules and tested in non-model *** models employing host non-specific parameters were successful in quantitatively predicting circuit behaviors,underscoring the potential of universal biological parts and predictive modeling in synthetic bioengineering.

关键词： circuit predictability host-independent genetic circuits host-nonspecific parameters parts characterization transcriptional regulatory modules

Ploidy and fruit trait variation in oil-tea Camellia:Implications for ploidy breeding

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Journal of Integrative Agriculture 2024年第8期23卷 2662-2673页

作者： Yanmin Li Liangjing Yin Xianyu He Cenlong Hu Ronghua Wu qian long Shixin Xiao Deyi Yuan Key Laboratory of Cultivation and Protection for Non-Wood Forest Trees of Ministry of Education/Key Laboratory of Non-Wood Forest Products of State Forestry Administration Central South University of Forestry and TechnologyChangsha 410004China qiandongnan Institute of Forestry Qiandongnan Miao and Dong Autonomous Prefecture 556000China Dongfeng Forest Farm of Liping County Qiandongnan Miao and Dong Autonomous Prefecture 557300China

Plant polyploidy often occurs in conjunction with higher yield and superior ***,obtaining polyploid germplasms is a significant part of *** oil-tea Camellia tree is an important native woody plant that produces high-quality edible oil and includes many species of Camellia with different ***,whether higher ploidy levels in oil-tea Camellia trees are related to better traits remains *** this study,the ploidy levels of 30 different oil-tea Camellia strains in three different species in the *** were determined by flow cytometry and chromosome preparation,and the phenotypic characteristics and fatty acid compositions of the fruits were examined by field observations and laboratory *** correlations between the ploidy level of oil-tea Camellia and the main traits of the fruit were *** results showed that 10 Camellia lanceoleosa strains were diploid,10 Camellia meiocarpa strains were tetraploid and 10 Camellia oleifera strains were *** *** had larger fruit size and weight,more seeds per fruit,greater seed weight per fruit,higher oil content and greater yield per crown width than tetraploid *** and diploid ***,but their fruit peel thickness and fresh seed rate were significantly lower,and these traits were significantly correlated with ploidy *** addition,in terms of fatty acid composition,hexaploid *** had a higher oleic acid content than tetraploid *** and diploid ***,but their linoleic acid,linolenic acid and arachidonic acid contents were *** contents of palmitic acid,stearic acid and total unsaturated fatty acids were not significantly correlated with ploidy *** conclusion,certain correlations exist between the main characteristics of oil-tea Camellia fruit and the ploidy level,and increasing the ploidy level led to an increase in fruit yield with no effect on oil *** discovery of variations in the m

关键词： oil-tea Camellia ploidy level fruit traits correlation polyploidization

粮食补贴政策的运行机制与改革逻辑——基于不确定性状态依存方法的解释

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西北农林科技大学学报（社会科学版） 2024年第2期24卷 24-34页

作者：钱煜昊钟钰钱龙南京财经大学粮食和物资学院南京210003 中国农业科学院农业经济与发展研究所北京100081

从种粮主体视角出发,引入劳动市场收入跨度概念,基于空间向量和不确定性状态依存方法构建了粮食补贴政策运行机制与改革逻辑的理论分析框架。基于该理论框架发现:(1)粮食补贴政策的核心作用之一是为粮食产业吸引较高技能禀赋的种粮者;(2... 详细信息

从种粮主体视角出发,引入劳动市场收入跨度概念,基于空间向量和不确定性状态依存方法构建了粮食补贴政策运行机制与改革逻辑的理论分析框架。基于该理论框架发现:(1)粮食补贴政策的核心作用之一是为粮食产业吸引较高技能禀赋的种粮者;(2)不同类型粮食补贴都会被当成收入性补贴,其产生的收入效应会起到扩大粮食种植面积和促进粮食科技进步的作用。因此应从政策空间、政策目标和政策弹性3个维度改革完善我国粮食补贴政策:一是进一步聚焦政策目标,提高技能型经营主体种粮意愿;二是充分发挥政策乘数效应,补贴聚焦产业链中后端;三是着力优化政策响应机制,抓住信息技术革命契机。

关键词：粮食补贴改革逻辑不确定性状态依存方法空间向量

有土斯有粮:高标准农田建设提高了粮食单产吗?

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南京农业大学学报（社会科学版） 2024年第1期24卷 132-143页

作者：钱龙杨光钟钰南京财经大学粮食和物资学院南京210003 成都市智慧蓉城研究院成都610041 中国农业科学院农业经济与发展研究所北京100081

作为“藏粮于地,藏粮于技”战略的重要政策实践,高标准农田建设被期待能够有效实现粮食增产和更好保障国家粮食安全。基于27个省(市、自治区)的面板数据,探索了高标准农田建设对粮食单产的影响及其可能机制。研究发现:(1)高标准农田建... 详细信息

作为“藏粮于地,藏粮于技”战略的重要政策实践,高标准农田建设被期待能够有效实现粮食增产和更好保障国家粮食安全。基于27个省(市、自治区)的面板数据,探索了高标准农田建设对粮食单产的影响及其可能机制。研究发现:(1)高标准农田建设能显著提高粮食单产。替换核心变量、进行非参数估计和考虑内生性的稳健性检验,均证实上述发现可信。(2)机制验证表明,高标准农田建设主要通过提升规模经营、促进技术进步和降低生产风险三大路径来提高粮食单产。(3)异质性分析发现,高标准农田建设对起伏度较小地形、粮食主产区、较发达地区的粮食单产促进效应更大。研究结果表明高标准农田建设确实是夯实粮食安全根基的重要举措,需扎实推进新一轮高标准农田建设工作。

关键词： “藏粮于地,藏粮于技”战略高标准农田建设粮食单产粮食安全

物质序章——大历史中传媒视角看物质时代崛起

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昭通学院学报 2024年第3期46卷 65-75页

作者：龙潜贵州民族大学文学院贵州贵阳550025

从殖民时代到成为一个独立国家,美国民主进程没有被奴役民族和弱势群体的份。家庭农场时代,广告多是传播关于地产买卖和人口买卖以及类似人口买卖的信息,它与现代传媒相去甚远。能源和机器所进行的大规模物质生产在工业化社会土壤中产生... 详细信息

从殖民时代到成为一个独立国家,美国民主进程没有被奴役民族和弱势群体的份。家庭农场时代,广告多是传播关于地产买卖和人口买卖以及类似人口买卖的信息,它与现代传媒相去甚远。能源和机器所进行的大规模物质生产在工业化社会土壤中产生,制造商赢得了有史以来世界商业史上最大的市场,秩序、效率和科学原则是不断彪柄的口号。现代社会充当文化改造主角的是大众物质消费,传媒自觉不自觉地左右人们的意识形态、生活方式和消费行为。

关键词：历史传媒物质消费

成效不彰VS行之有效:粮食安全省长责任制促进了粮食生产吗?

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经济评论 2024年第2期 22-35页

作者：甘林针钱龙钟钰重庆社会科学院 400020 南京财经大学粮食和物资学院 210023 中国农业科学院农业经济与发展研究所 100081

粮食安全省长责任制是压实地方粮食安全主体责任,保障国家粮食安全的重要制度。本文利用2004—2020年31个省份的面板数据,运用双重差分法,验证了粮食安全省长责任制对粮食生产的影响。研究发现,粮食安全省长责任制对粮食生产有显著促进... 详细信息

粮食安全省长责任制是压实地方粮食安全主体责任,保障国家粮食安全的重要制度。本文利用2004—2020年31个省份的面板数据,运用双重差分法,验证了粮食安全省长责任制对粮食生产的影响。研究发现,粮食安全省长责任制对粮食生产有显著促进作用,更换实证模型、安慰剂检验、调整样本量和替换被解释变量的稳健性检验均支持这一核心结论。进一步的机制分析发现,粮食安全省长责任制通过提高地方政府和领导抓粮积极性,实现促进粮食生产的目标。为更好落实粮食安全省长责任制,稳定粮食生产,要不断优化粮食安全省长责任制考核指标体系、持续加强地方党政领导干部的粮食安全主体意识、严格落实粮食安全省长责任制考核激励机制。

关键词：粮食安全省长责任制粮食生产粮食安全

贝伐珠单抗联合紫杉醇和卡铂治疗复发性卵巢癌的临床疗效观察

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科技与健康 2024年第3期3卷 57-59页

作者：龙倩黔东南州人民医院肿瘤一病区贵州黔东南556000

观察贝伐珠单抗联合紫杉醇和卡铂治疗复发性卵巢癌的临床疗效。抽取2020年1月-2022年12月黔东南州人民医院收治的40例复发性卵巢癌患者为研究对象,随机将其分为两组,每组各20例。对照组采用紫杉醇、卡铂治疗,观察组在对照组基础上加用... 详细信息

观察贝伐珠单抗联合紫杉醇和卡铂治疗复发性卵巢癌的临床疗效。抽取2020年1月-2022年12月黔东南州人民医院收治的40例复发性卵巢癌患者为研究对象,随机将其分为两组,每组各20例。对照组采用紫杉醇、卡铂治疗,观察组在对照组基础上加用贝伐珠单抗,比较两组间除不良反应外各项指标结果(P<0.05)。研究发现,贝伐珠单抗联合紫杉醇和卡铂可以在复发性卵巢癌的治疗中起到积极作用。

关键词：复发性卵巢癌贝伐珠单抗紫杉醇卡铂临床疗效