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企业数字化转型与全球价值链参与

管理工程学报 2025年第1期39卷 15-31页

作者：李鑫佟岩曹丰北京理工大学管理学院北京100081 湖南大学工商管理学院湖南长沙410082

本文立足“逆全球化”时代数字经济发展迅速的现实背景,利用2010年至2016年中国A股上市公司与中国海关数据库的合并数据,实证检验了企业数字化转型对其全球价值链参与的影响。研究表明,数字化转型能够促进企业更好地融入全球价值链,并... 详细信息

本文立足“逆全球化”时代数字经济发展迅速的现实背景,利用2010年至2016年中国A股上市公司与中国海关数据库的合并数据,实证检验了企业数字化转型对其全球价值链参与的影响。研究表明,数字化转型能够促进企业更好地融入全球价值链,并且该结论在经过一系列稳健性检验后依然成立。影响机制检验发现,企业数字化转型对全球价值链嵌入的提升作用主要通过缓解融资约束和提高生产效率来实现。异质性检验结果表明,当数字化转型基础较好、劳动力需求较高以及成本加成较低时,企业数字化转型对全球价值链参与的影响更为凸显。本文丰富和拓展了企业数字化转型影响机制与经济后果的研究框架,为企业更好地融入全球价值链分工体系、实现高质量发展找到了新的经验证据,对于企业数字化相关政策的制定与调整也具有一定的参考价值。

关键词：数字化转型全球价值链嵌入融资约束生产效率

Positive effect of Mo on mechanical properties of a Ni-42W-10Co-x Mo medium heavy alloy

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China Foundry 2025年

作者： Guo-xin cao Jian-xin Dong Yong-sheng He He Jiang Fang Hao Zhi-hua Nie Teng-fei Ma Bao-quan Fu School of Materials Science and Engineering University of Science and Technology Beijing Xi'an Superalloy Technology Co. Ltd. School of Materials Science and Engineering Beijing Institute of Technology Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou University

In this study,a novel Ni-W-Co-Mo medium heavy alloy (MHA) was designed to improve its mechanical strength via Mo *** the Ni-42W-10Co-xM o alloy series,where x represents the weight percent of Mo and varies between 0,1,2,5,and 10,the microstructure transitions from a dendritic structure to a hypoeutectic structure as the Mo content increases from 0 to 5wt.%.Moreover,as the Mo content increases from 0to 10wt.%,the distribution of theμ-phase shifts from being individually dispersed to forming aggregates,and its volume fraction rises from 0.5%to 7.9%.Notably,theμ-phase evolves into an eutectic microstructure,which helps in minimizing the segregation of *** change is accompanied by a substantial enhancement in mechanical properties;specifically,the compressive yield strength at room temperature increases from 350 MPa to 646 MPa,indicating a significant 85%***,the microhardness increases from 230 HV to 304 *** dynamics simulations further reveal that the strengthening mechanism of Ni-42W-10Co-xM o alloys is Mo-induced solid solution strengthening and precipitation strengthening.

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Laser assisted phase transformation of carbon-based transition metal oxide electrode for high-performance supercapacitor application

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Science China Chemistry 2025年

作者： Mingzhen Xiu Jianghong Zhang Yu Lu Xun cao Kang Huang Siyu Zhu Bowei Zhang Yu Liang Chunwang Zhao Junsheng Wu Yizhong Huang School of Materials Science and Engineering Nanyang Technological University Energy Research Institute Interdisciplinary Graduate Programme Nanyang Technological University Institute of Sustainability for Chemicals Energy and Environment Agency for Science Technology and ResearchSingapore Institute of Advanced Materials and Technology University of Science and Technology Beijing School of Materials Science and Technology Shenyang University of Chemical Technology School of Materials Science and Hydrogen Energy Foshan University

Transitional metal oxides have a wide range of applications due to their superior *** enhanced performance of metal oxide relies on their desirable oxidation states,which is challenging to achieve and requires complex *** study demonstrates a facile strategy enabling rapid phase transformation of transition metal *** approach involves synthesis of a tetragonal Mn3O4/carbon cloth composite using the liquid plasma discharge deposition （LPDD） technique,followed by laser irradiation with the presence of ethylene glycol under an N2gas *** resulting face-centered cubic MnO/carbon cloth electrode exhibits an excellent capacitance of 1,125 F g-1at 2 A g-1,with remarkable capacitance retention of 95%after10,000 *** approach can be extended to other transition metals including Co,Cu,Cr,Fe,Ni,and *** simulations reveal the significance of ethylene glycol and the underlying mechanism associated with the phase transformation of transition metal *** present study offers a powerful technique for the phase transformation of transition metal oxide which can guide the development of new electrode materials with enhanced electrochemical properties for high-performance energy storage applications.

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Can patients with mild non-neoplastic lesions diagnosed at baseline screening be safely exempt from surveillance: evidence from multicenter community-based cohorts

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Science China Life Sciences 2025年第1期68卷 263-271页

作者： Siyi He Zhiyi Zhang Guohui Song Zhenhai Wang Chunyun Dai Shipeng Yan Kun Jiang Bingbing Song He Li Maomao cao Dianqin Sun Fan Yang Xinxin Yan Shaoli Zhang Yi Teng Qianru Li Changfa Xia Wanqing Chen Office of Cancer Screening National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical College Department of Gastroenterology Gansu Wuwei Tumor Hospital Cixian Cancer Institute Linzhou Cancer Hospital Center for Disease Control and Prevention of Sheyang County Department of Cancer Prevention and Control Hunan Cancer Hospital and The Affiliated Cancer Hospital of Xiangya School of MedicineCentral South University Luoshan Center for Disease Control and Prevention Office for Cancer Control and Research Affiliated Cancer Hospital of Harbin Medical University

Surveillance recommendations for gastric cancer（GC） in current guidelines focused on advanced precancerous lesions and were based on precise diagnosis of severity/extent of baseline lesions. We aimed to develop a less endoscopy-related equipment-dependent risk-stratification tool, and assessed whether mild-precursor-lesion patients can be safely exempt from surveillance. In the multicenter communitybased cohort, 75,051 participants receiving baseline endoscopy were enrolled during 2015–2017 and followed-up until 2021. Cumulative incidence rates（CIRs） of GC for precancerous-conditions were calculated by Kaplan-Meier method and compared by Log-rank tests. Mixedeffects Cox regression models were used to detect potential factors for progression towards GC. A risk score was calculated as counts of selected factors. An independent cohort, including 26,586 participants was used for external validation. During a median follow-up of 6.25 years, CIRs of GC were 0.302%, 0.436%, and 4.756% for normal group, non-neoplastic（atrophic gastritis/intestinal metaplasia） and neoplastic lesions（low-grade/high-grade dysplasia）, respectively(Ptrend<0.001). Four predictors, including male, ≥60 years, smoking, and limited vegetable consumption, were selected for risk-stratification. High-risk patients（≥3 risk factors） with non-neoplastic lesions showed higher GC risks（adjusted HR=7.73, 95%CI: 4.29–13.92）, and their four-year CIR reached the one-year CIR of neoplastic lesions. Further categorizing non-neoplastic lesions by histological grade, both patients with moderate-to-severe lesions（aHR=3.07, 95%CI: 1.67–5.64） and high-risk patients with mild lesions（aHR=7.29, 95%CI: 3.58–14.86） showed higher risks. Consistent trends were observed in validation cohort. High-risk mild-precursor-lesion patients should receive surveillance within 3–5 years after baseline screening. Our study provides evidence on supplementing current guideline recommendations.

关键词： stomach neoplasms precancerous conditions cancer screening cumulative incidence risk stratification

场域视角下高校创新创业教育的现实困境与路径优化

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黑龙江高教研究 2025年第2期43卷 149-154页

作者：曹文军南京林业大学江苏南京210037

作为当代大学转型发展的新取向与教育教学的新内容,创新创业教育旨在基于学生个性培养更具开创性的社会建设人才。从场域的视角看,形成教育新惯习、建构行动者网络与实现主体同场共生是高校创新创业教育取得良好效果的必然要求。当前创... 详细信息

作为当代大学转型发展的新取向与教育教学的新内容,创新创业教育旨在基于学生个性培养更具开创性的社会建设人才。从场域的视角看,形成教育新惯习、建构行动者网络与实现主体同场共生是高校创新创业教育取得良好效果的必然要求。当前创新创业教育的实践中存在既有惯习挟持、专业壁垒掣肘、隔“场”喊话盛行等问题,阻碍了高校创新创业教育的发展。为此,需要全员行动,超越教育惯习同场域结构的消极互动关系,推动高校创新创业教育微观行为与宏观结构在中观场域的层面走向统合。具体路径是基于文化生态激活主体内生动力、基于组织生态贯通协同育人体系、基于管理生态优化环境保障机制。

关键词：创新创业教育场域惯习行动者网络

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

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轮式格斗机器人的设计与实现

现代电子技术 2025年第2期48卷 124-130页

作者：李辉曹月花杭州电子科技大学信息工程学院浙江杭州310000

面向本科机器人方向实践教学,设计一款轮式格斗机器人。该机器人可以实现自主登台、自动巡航、自主视觉寻敌攻击、落台后重新登台等功能。首先,进行机器人的机械结构设计。通过合理的机械结构设计以及合理的传感器安装布置,可以有效改... 详细信息

面向本科机器人方向实践教学,设计一款轮式格斗机器人。该机器人可以实现自主登台、自动巡航、自主视觉寻敌攻击、落台后重新登台等功能。首先,进行机器人的机械结构设计。通过合理的机械结构设计以及合理的传感器安装布置,可以有效改善机器人的结构强度、灵活性、稳定性和机动性。其次,进行机器人控制系统设计,其中,包括机器人控制系统元器件选型设计、机器人的控制策略及控制算法设计、路径规划算法设计、目标识别与视觉跟踪算法设计。最后,采用现场测试的方法对机器人的性能进行优化提升。在不同环境下,通过机器人现场表现进行测试和分析,评估机器人的性能和稳定性,并针对性地进行改进和优化。通过轮式格斗机器人的设计与实现训练,有助于提升机器人工程专业本科生在机器人领域的设计实践和问题分析能力。

关键词：格斗机器人机械结构设计控制系统设计控制策略路径规划目标识别视觉跟踪

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高考数学试题情境的价值、质量与考态分析

教学与管理 2025年第1期 63-66页

作者：曹翛骛陕西省西安市昆仑中学西安710043

鉴于试题情境影响测评目的的实现,首先探讨试题情境的测评价值和质量特征,并建构质量特征的分层评价标准。其次,以2024年高考全国卷和地方卷为研究单元,以上述评价标准为研究工具,研究得出高考数学试题情境综合质量的相对排序为:北京卷... 详细信息

鉴于试题情境影响测评目的的实现,首先探讨试题情境的测评价值和质量特征,并建构质量特征的分层评价标准。其次,以2024年高考全国卷和地方卷为研究单元,以上述评价标准为研究工具,研究得出高考数学试题情境综合质量的相对排序为:北京卷≈上海卷>新高考I卷>新高考II卷≈甲卷(理科)≈天津卷;虽然高考数学试题的情境存在差异性,但具有以下共性:试题情境主要承载单一的工具或发展价值;真实性与新颖性的水平较低;融合性水平较高。最后,提出重视情境教育、引导学生深度学习的教学建议。

关键词：高考数学试题情境 2024年高考数学试卷情境呈现

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基于格网尺度的黄河中游地区经济城镇化与PM_(2.5)浓度的脱钩关系研究

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生态经济 2025年第1期41卷 132-139页

作者：沈威曹威威洛阳师范学院地理与旅游学院河南洛阳471022 河南大学地理与环境学院河南开封475004

针对当前经济城镇化参量公里网格数据的缺乏,以黄河中游地区为例,提出一种利用1995—2018年高精度土地利用栅格数据和统计年鉴数据的经济城镇化参量空间化模拟方法,并分析格网尺度下黄河中游地区经济城镇化与PM2.5浓度的脱钩关系演变。... 详细信息

针对当前经济城镇化参量公里网格数据的缺乏,以黄河中游地区为例,提出一种利用1995—2018年高精度土地利用栅格数据和统计年鉴数据的经济城镇化参量空间化模拟方法,并分析格网尺度下黄河中游地区经济城镇化与PM2.5浓度的脱钩关系演变。结果表明:(1)黄河中游地区经济城镇化水平呈现出以兰西城市群、西安城市圈、太原城市圈、郑州—洛阳城市带为核心的多核心圈层结构。(2)在空间格局演变上,不同区域经济城镇化的扩张模式存在差异。受地形限制和水文条件限制,洛河流域、汾河流域、关中平原、太原城市圈经济城镇化呈现以中心城市为核心的带状扩张特征;兰西城市群、郑州—洛阳城市带、呼和浩特市呈现以中心城市为核心的圈层式扩张特征。(3)2005年之后,黄河中游中东部地区开始出现脱钩转折点;2010年之后,黄河中游西部地区开始出现脱钩转折点,但由于西部大开发战略的实施,导致2015—2018年甘肃和宁夏南部扩张负脱钩区面积显著增加,经济城镇化与环境污染的脱钩关系再次发生转变。

关键词：经济城镇化土地利用回归模型 PM2.5浓度脱钩状态