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全球价值链嵌入对企业不同类型技术创新的影响研究

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产业经济研究 2024年第2期 1-14,44页

作者：李嘉欣武力超吕越清华大学公共管理学院北京100084 厦门大学经济学院福建厦门361005 对外经济贸易大学国家对外开放研究院北京100029

基于“双循环”视角和实现创新驱动的经济高质量发展目标,研究了企业在全球价值链(GVC)上游嵌入度和全球价值链(GVC)下游嵌入度对企业国内外不同类型技术创新的影响效应和机制,包括国内技术创新和国外技术创新。研究发现:GVC上游嵌入度... 详细信息

基于“双循环”视角和实现创新驱动的经济高质量发展目标,研究了企业在全球价值链(GVC)上游嵌入度和全球价值链(GVC)下游嵌入度对企业国内外不同类型技术创新的影响效应和机制,包括国内技术创新和国外技术创新。研究发现:GVC上游嵌入度显著促进了国内技术创新,对外资企业、一般贸易企业和高行业竞争度企业的影响更明显,而GVC上游嵌入度对国外技术创新没有产生显著的促进效应;GVC下游嵌入度则对企业国内外技术创新均产生抑制效应,对内资企业、一般贸易企业和低竞争程度企业的作用尤其明显。机制检验表明,吸收能力有助于增强GVC上游嵌入度对国内创新的促进效应,同时弱化GVC下游环节嵌入对企业国内外技术创新的阻碍作用。进一步分析发现,GVC上游嵌入度对绿色技术创新的促进效应和GVC下游嵌入度的绿色技术创新抑制效应,仅在非污染行业中存在。研究结论为我国在全球价值链嵌入过程中,促进企业技术创新能力提升以及实现产业升级提供了重要的政策参考。

关键词：全球价值链国内技术创新国外技术创新吸收能力绿色技术创新

贸易便利化对我国跨境电商发展的影响研究——基于RCEP成员国的分析

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工信财经科技 2024年第3期 98-115页

作者：武力超吴孟煜朱桦田雯雯厦门大学经济学院国际经济与贸易系

RCEP的生效标志着全球经贸规模最大、最具发展潜力的自由贸易区的正式落地,将为其成员国的外贸增长提供新动能。在疫情的冲击及贸易保护主义抬头的背景下,跨境电商仍然表现出强劲的增长韧性,但其作为新兴业态模式,仍面临着贸易非便利因... 详细信息

RCEP的生效标志着全球经贸规模最大、最具发展潜力的自由贸易区的正式落地,将为其成员国的外贸增长提供新动能。在疫情的冲击及贸易保护主义抬头的背景下,跨境电商仍然表现出强劲的增长韧性,但其作为新兴业态模式,仍面临着贸易非便利因素的阻碍。本文聚焦于贸易便利化以及各因素对跨境电商进出口发展的影响。运用主成分分析法建立贸易便利化综合评价体系,并对RCEP成员国2012—2019年的贸易便利化水平进行测度,比较成员国各项贸易便利化水平指标差异,随后基于修正后的引力模型对RCEP成员国2012—2019年的面板数据进行回归。研究表明,贸易便利化能够显著促进跨境电商进出口的发展,其效应要强于关税水平,且对出口端的影响更大;文化距离在跨境电商业态中的影响要强于地理距离。分指标回归的结果显示,在贸易便利化下的四个一级指标中,金融与电子商务对跨境电商发展的影响最大。基于以上实证结果,本文为中国推进RCEP贸易便利化建设提供新思路。

关键词：贸易便利化跨境电商 RCEP 引力模型

Effects of enrichmemt planting with native tree species on bacterial community structure and potential impact on Eucalyptus plantations in southern China

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Journal of Forestry Research 2022年第4期33卷 1349-1363页

作者： Yuxing Xu Chao Li Wankuan Zhu Zhichao Wang lichao wu Apeng Du Key Laboratory of Soil and Water Conservation and Desertifi cation Combating of Hunan Province College of ForestryCentral South University of Forestry and TechnologyChangshaHunan 410004People’s Republic of China China Eucalypt Research Centre(CERC) Chinese Academy of Forestry(CAF)ZhanjiangGuangdong 524022People’s Republic of China Guangdong Zhanjiang Eucalyptus Plantation Ecosystem Research Station ZhanjiangGuangdong 524022People’s Republic of China

Multi-generational planting of Eucalyptus species degrades soil quality but the introduction of legumes can improve soil fertility and microbial ***,the effects of introducing non-legume native tree species on soil nutrients and bacterial community structure remain poorly *** study investigated the impacts of the conversion of third generation monoculture Eucalyptus plantations to mixed systems including Eucalyptus urograndis with Cinnamomum camphora(EC)and *** with Castanopsis hystrix(EH),on soil chemical and biochemical properties and bacterial community structure,diversity and *** generation *** plantations were the *** show that planting the third generation Eucalyptus led to a significant decrease in p H,organic matter,nutrient content,enzyme activities(invertin,acid phosphataes,and urease),and bacterialα-diversity compare to the ***,the mixed planting showed significant improvement in soil chemical and biochemical attributes and bacterialα-diversity,although the *** and *** planting had no ***(oligotrophic bacteria)were significantly enriched in third generation Eucalyptus and Eucalyptus+***,while proteobacteria increased significantly in the *** with *** *** relative abundance of multiple metabolic pathways increased significantly in the third generation Eucalyptus plantations whereas membrane transportrelated genes were enriched in soils of the mixed *** changes in bacterial community structures in the two mixed systems were driven by diversity,organic matter and acid phosphatase,while bacterial functions were affected by invertase,NO_(3)^(-)-N,diversity and *** results suggest that the transformation of successive monoculture Eucalyptus plantations into mixed plantations reduces the depletion of soil nutrients and enhances the ecological function of soil microorganisms.

关键词： Soil chemical propertie Enzyme activity 16S rRNA amplicon sequencing Bacterial community structure Tax4Fun function prediction

社会资本与城市竞争力的关系——基于国际友好城市视角

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深圳社会科学 2024年第4期7卷 65-78页

作者：武力超朱桦田雯雯娄逸娴方心怡厦门大学经济学院国际经济与贸易系福建厦门361005 上海财经大学经济学院上海200433

随着经济全球化的深入发展,经济竞争的重点逐渐从独立的要素产业扩大到城市综合实力水平的各个方面。城市竞争力是城市对外发展、创造财富并提升城市社会经济地位的重要综合能力,其强弱关系着城市的未来发展。社会资本能够促进地区的经... 详细信息

随着经济全球化的深入发展,经济竞争的重点逐渐从独立的要素产业扩大到城市综合实力水平的各个方面。城市竞争力是城市对外发展、创造财富并提升城市社会经济地位的重要综合能力,其强弱关系着城市的未来发展。社会资本能够促进地区的经济增长,正成为城市竞争力的主要来源。国际友好城市构建的城市网络是社会资本的重要组成部分,可以在一定程度上对城市的社会资本丰裕程度进行阐释。基于2012—2018年全国284个地级市的面板统计数据进行实证研究,结果表明,社会资本对城市竞争力的发展有积极的影响,即社会资本越丰厚,其城市竞争力越强,并且通过了一系列稳健性检验。这种影响在一定程度上是由社会资本的独特属性引起的,社会资本作为社会各主体之间的粘合剂,虽然没有直接参与社会生产,但仍为城市竞争力的发展做出重要贡献。进一步探讨社会资本促进城市竞争力提升的作用渠道发现社会资本通过提高主体间互信水平、促进贸易往来以及提高政府治理能力这三条可能的渠道对城市竞争力产生积极影响。社会资本对于提高城市竞争力,并由城市高质量发展带动经济高质量发展具有现实意义。

关键词：社会资本城市竞争力国际友好城市高质量发展

Recent advances in transition metal phosphide materials:Synthesis and applications in supercapacitors

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Nano Materials Science 2024年第2期6卷 174-192页

作者： Ge Li Yu Feng Yi Yang Xiaoliang wu Xiumei Song lichao Tan College of Chemistry Chemical Engineering and Resource UtilizationNortheast Forestry University26 Hexing RoadHarbin150040PR China Institute of Carbon Neutrality Zhejiang Wanli UniversityNingbo315100PR China School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin150040PR China

Supercapacitors(SCs)are considered promising energy storge systems because of their outstanding power density,fast charge and discharge rate and long-term cycling *** exploitation of cheap and efficient electrode materials is the key to improve the performance of *** the battery-type materials,transition metal phosphides(TMPs)possess high theoretical specific capacity,good electrical conductivity and superior structural stability,which have been extensively studied to be electrode materials for *** this review,we summarize the up-to-date progress on TMPs materials from diversified synthetic methods,diverse nanostructures and several prominent TMPs and their composites in application of *** the end,we also propose the remaining challenges toward the rational discovery and synthesis of high-performance TMP electrodes materials for energy storage.

关键词： Transition metal phosphides Cobalt phosphide Nickel phosphides Electrode materials Supercapacitor

TaMYB72 directly activates the expression of TaFT to promote heading and enhance grain yield traits in wheat(Triticum aestivum L.)

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Journal of Integrative Plant Biology 2024年第7期66卷 1266-1269页

作者： Lifen wu Zhencheng Xie Danping Li Yaoyu Chen Chuan Xia Xiuying Kong Xu Liu lichao Zhang State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop Sciencesthe Chinese Academy of Agricultural SciencesBeijing 100081China State Key Laboratory of North China Crop Improvement and Regulation Hebei Sub‐Center for National Maize Improvement CenterCollege of AgronomyHebei Agricultural UniversityBaoding 071001China

Wheat(Triticum aestivum L.)is a staple food for approximately half the global *** the population continues to grow,the demand for high-yielding varieties is increasing(Zorb et al.,2018).Higher yields can be achieved by increasing the number and weight of grains produced and by optimizing heading dates to maximize production in local environments(Sakuma and Schnurbusch,2020).

关键词： heading Wheat yielding

免炼山免挖穴简力定植对桉树人工林根系和生长的影响

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桉树科技 2024年第2期41卷 65-70页

作者：邓善宝梁天合梁雪雨王政烨陈利军曹继钊吴立潮朱原立广西壮族自治区国有七坡林场广西南宁530034 中南林业科技大学林学院/水土保持与荒漠化防治湖南省高等学校重点实验室湖南长沙410004 广西壮族自治区林业科学研究院广西南宁530002

传统的炼山、大穴造林方式易引桉树人工林起水土流失、地力下降等一系列问题,免炼山、免挖穴、简力定植可能是解决上述问题的重要手段。文章以尾巨桉为研究对象,布置了桉树免炼山、免挖穴、简力定植方式并以大穴造林为对照,探讨两种方... 详细信息

传统的炼山、大穴造林方式易引桉树人工林起水土流失、地力下降等一系列问题,免炼山、免挖穴、简力定植可能是解决上述问题的重要手段。文章以尾巨桉为研究对象,布置了桉树免炼山、免挖穴、简力定植方式并以大穴造林为对照,探讨两种方式对桉树人工林根系与蓄积量的影响。结果表明:造林5年后两种造林方式桉树人工林的根系主要分布范围在土层0~70 cm且根系数量多分布于土层20~50 cm,两种造林方式间差异不显著。造林后前2年,简力定植区的桉树胸径、树高与蓄积量略低于对照区但差异不显著;造林3年后逐渐反超,至第五年简力定植区桉树胸径、树高、蓄积量相较于对照区分别增长4.90%、5.13%、15.00%。简力定植造林未对林木蓄积量产生不良影响,反而提高了林木的生长量,对解决桉树人工林地力下降等问题具有较好的效果。

关键词：桉树人工林免炼山简力定植根系分布蓄积量

Combined application of organic fertilizer and chemical fertilizer alleviates the kernel position effect in summer maize by promoting post-silking nitrogen uptake and dry matter accumulation

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Journal of Integrative Agriculture 2024年第4期23卷 1179-1194页

作者： lichao Zhai Lihua Zhang Yongzeng Cui Lifang Zhai Mengjing Zheng Yanrong Yao Jingting Zhang Wanbin Hou Liyong wu Xiuling Jia Institute of Cereal and Oil Crops Hebei Academy of Agriculture and Forestry Sciences/Key Laboratory of Crop Cultivation Physiology and Green Production of Hebei ProvinceShijiazhuang 050035China Hebei Science and Technology Innovation Service Center Shijiazhuang 050051China Yongnian Agricultural Technology Extension Center Handan 057150China Ningjin Agricultural Technology Extension Center Xingtai 055550China

Adjusting agronomic measures to alleviate the kernel position effect in maize is important for ensuring high *** order to clarify whether the combined application of organic fertilizer and chemical fertilizer(CAOFCF)can alleviate the kernel position effect of summer maize,field experiments were conducted during the 2019 and 2020 growing seasons,and five treatments were assessed:CF,100%chemical fertilizer;OFCF1,15%organic fertilizer+85%chemical fertilizer;OFCF2,30%organic fertilizer+70%chemical fertilizer;OFCF3,45%organic fertilizer+55%chemical fertilizer;and OFCF4,60%organic fertilizer+40%chemical *** with the CF treatment,the OFCF1 and OFCF2 treatments significantly alleviated the kernel position effect by increasing the weight ratio of inferior kernels to superior kernels and reducing the weight gap between the superior and inferior *** effects were largely due to the improved filling and starch accumulation of inferior ***,there were no obvious differences in the kernel position effect among plants treated with CF,OFCF3,or OFCF4 in most *** area indexes,post-silking photosynthetic rates,and net assimilation rates were higher in plants treated with OFCF1 or OFCF2 than in those treated with CF,reflecting an enhanced photosynthetic capacity and improved postsilking dry matter accumulation(DMA)in the plants treated with OFCF1 or *** with the CF treatment,the OFCF1 and OFCF2 treatments increased post-silking N uptake by 66.3 and 75.5%,respectively,which was the major factor driving post-silking photosynthetic capacity and ***,the increases in root DMA and zeatin riboside content observed following the OFCF1 and OFCF2 treatments resulted in reduced root senescence,which is associated with an increased post-silking N *** showed that post-silking N uptake,DMA,and grain yield in summer maize were negatively correlated with the kernel position *** conclusion,the combined application of

关键词： chemical fertilizer dry mater accumulation kernel position effect N uptake organic fertilizer

Mechanical behaviours of bedded sandstone under hydromechanical coupling

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1245-1261页

作者： Junwen Zhang Zhixiang Song lichao Zhang Shaokang wu Shanyong Wang Yang Zhang Xukai Dong Jinxin Wang Yanbo Han Baohua Kan School of Energy and Mining Engineering China University of Mining and Technology (Beijing)Beijing100083China Jarud Banner Zhahanao'er Coal Industry Co. Ltd.ZhaluteqiInner Mongolia029200China Priority Research Centre for Geotechnical Science & Engineering The University of NewcastleCallaghanNSW 2308Australia

The combination of the dipping effect and hydromechanical(H-M)coupling effect can easily lead to water inrush disasters in water-rich roadways with different dip angles in coal ***,H-M coupling tests of bedded sandstones under identical osmotic pressure and various confining pressures were ***,the evolution curves of stress-strain,permeability and damage,macro-and mesoscopic failure characteristics were ***,the mechanical behaviour was characterized,and finally the failure mechanism was *** results showed that:(1)The failure of the sandstone with the bedding angle of 45°or 60°was the structure-dominant type,while that with the bedding angle of 0°,30°or 90°was the force-dominant type.(2)When the bedding angle was in the range of(0°,30°)or(45°,90°),the confining pressure played a dominant role in influencing the peak ***,withinβ∈(30°,45°),the bedding effect played a dominant role in the peak strength.(3)With the increase in bedding angle,the cohesion increased first,then decreased and finally increased,while the internal friction angle was the opposite.(4)When the bedding angle was 0°or 30°,the“water wedging”effect and the“bedding buckling”effect would lead to the forking or converging shear *** the bedding angle was 45°or 60°,the sliding friction effect would lead to the shear slipping *** the bedding angle was 90°,the combination of the“bedding buckling”effect and shear effect would lead to the mixed tension-shear *** above conclusions obtained are helpful for the prevention of water inrush disasters in water-rich roadways with different dips in coal mines.

关键词： Hydromechanical coupling Bedded sandstones Mechanical behaviour Bedding effect Failure mechanism