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Aromatic inorganic acid radical

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Science China Chemistry 2019年第12期62卷 1656-1665页

作者： jiawen Zhou Weiya Zhu Miao Zeng Qingqing Yang Ping Li Linfeng Lan Junbiao Peng Yuan Li Fei Huang Yong cao State Key Laboratory of Luminescent Materials and Devices Institute of Polymer Optoelectronic Materials and DevicesSouth China University of TechnologyGuangzhou 510640China Key Laboratory for Organic Electronics and Information Displays&Institute of Advanced Materials Jiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing University of Posts&TelecommunicationsNanjing 210023China

Stable radicals are challenging to prepare due to their intrinsic high ***,three trisphenolamine radicals were readily synthesized and exhibited unexpected thermal/electrochemical stability and semiconductor *** three nitroxide radicals could be considered as a class of aromatized nitro groups or HNO3 *** closed-shell nitro-like and open-shell nitroxide resonance structure contribute to their outstanding ***,the tunable ground states,extremely low band gap and p-type charge transport properties were systematically *** importantly,the work presents the concept of aromatic inorganic acid radical(AIAR)and aggregation-induced radical(AIR)mechanism to understand the intrinsic structureproperty relationship of these *** addition,we provide a novel strategy for the design of stable and low bandgap radicals for organic electronics,magnetics,spintronics,etc.

关键词： organic electronics aromatic nitric acid radical aggregation-induced radical polycyclic aromatic hydrocarbons spintronics

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

Assessment of Risk of Establishment of Wheat Dwarf Bunt (Tilletia controversa) in China

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Journal of Integrative Agriculture 2013年第1期12卷 87-94页

作者： jiawen-ming ZHOU Yi-lin DUAN Xia-yu LUO Yong DING Sheng-li cao Xue-ren Bruce D L Fitt State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Agricultural College Shihezi University Department of Plant Pathology China Agricultural University University of Hertfordshire

Wheat dwarf bunt, caused by Tilletia controversa Kühn （TCK）, is an important quarantine wheat disease throughout the world. Based on published research results of the biology and the epidemiology of the disease, the main factors including temperature, humidity, snow cover, and their parameters relating to teliospore germination, infection and epidemics of TCK were determined. The geophytopathological models for the risk analysis of wheat dwarf bunt establishment were modified. Fifty-year meteorologic data from about 500 weather stations in China were used to calculate the probabilities of TCK establishment in different geographic sites with the models. The map that displays the establishment risk of TCK in winter wheat growing regions in China was generated by using geographical information system （GIS）. The zones showing high, moderate, low, and very low, including no risk, of TCK establishment accounted for 27.33, 27.69, 38.12, and 6.86% of total winter wheat growing areas in China, respectively. These results will provide useful information to formulate quarantine regulations and wheat importation policy in China.

关键词： wheat dwarf bunt geophytopathological model geographical information system risk analysis

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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蝴蝶物种自动识别研究的生态照片数据集

中国科学数据（中英文网络版） 2019年第3期4卷 189-194页

作者：谢娟英曹嘉文马丽滨甄文全陈振宁李晓东李后魂许升全陕西师范大学计算机科学学院西安710119 陕西师范大学生命科学学院西安710119 钦州学院海洋学院广西钦州535011 青海师范大学生命科学学院西宁810008 河池学院化学与生物工程学院广西河池546300 南开大学生命科学学院天津300071

蝴蝶物种的自动识别能够为生态环境监测、生物多样性保护、害虫防治等领域提供技术支持,减少对专家人工鉴定的依赖。针对目前蝴蝶自动识别研究中主要依靠标本照片,缺少蝴蝶自然生态照片数据的状况,本数据集提供了一组蝴蝶生态照片、对应... 详细信息

蝴蝶物种的自动识别能够为生态环境监测、生物多样性保护、害虫防治等领域提供技术支持,减少对专家人工鉴定的依赖。针对目前蝴蝶自动识别研究中主要依靠标本照片,缺少蝴蝶自然生态照片数据的状况,本数据集提供了一组蝴蝶生态照片、对应的PASCAL VOC 2007格式的标注文件以及每张照片的掩模。本数据集包含的721张中国蝴蝶生态图片,涵盖94种蝴蝶。每张照片对应一个标注文件,标注文件中包含照片大小、照片中蝴蝶的种类和位置等信息。每张照片的掩模对应照片中的蝴蝶区域。本数据集可为自动识别、目标检测、图像分割和昆虫分类等研究提供基础数据。

关键词：蝴蝶分类生态照片自动识别目标检测

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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