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CCS Chemistry 2024年第6期6卷 1591-1599页

作者： Fulin Zhou Haojie Dai Shan Tang yongfeng Zhou Frontiers Science Center for Transformative Molecules Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240

Aiming at accessing polyethylene-bearing in-chain degradable functionality,copolymerization of carbon dioxide(CO_(2))with ethylene has long been recognized as a significant but highly challenging ***,most trials have resulted in ethylene homopolymerization because of the endothermic property and high energy barriers of CO_(2)insertion during polymer chain *** we report an unprecedented tandem reaction protocol for the synthesis of polyethylenes with in-chain carbonyls from CO_(2)and ethylene by the combination of photocatalytic CO_(2)reduction and palladium-catalyzed coordination/insertion *** protocol provides an easy way to adjust the carbonyl content(from 0.13 to 12 mol%)and insertion selectivity(up to 99%isolated carbonyls)of the polyethylene copolymers,which enables the polymers tomaintain the main properties of highdensity polyethylene and simultaneously endows them with good *** addition,besides apolar polyethylene copolymers,polar-functionalized polyethylenes with in-chain isolated carbonyls can also be synthesized from CO_(2),ethylene and a polar monomer using the same *** believe our present work sheds new light on the synthesis of degradable polyethylenes by employing CO_(2)as a green carbonyl source.

关键词： carbon dioxide coordination polymerization polyethylene photoreduction photodegradation

Surface Defect Detection and Evaluation Method of Large Wind Turbine Blades Based on an Improved Deeplabv3+Deep Learning Model

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Structural Durability & Health Monitoring 2024年第5期18卷 553-575页

作者： Wanrun Li Wenhai Zhao Tongtong Wang yongfeng Du Institution of Earthquake Protection and Disaster Mitigation Lanzhou University of TechnologyLanzhou730050China International Research Base on Seismic Mitigation and Isolation of GANSU Province Lanzhou University of TechnologyLanzhou730050China Disaster Prevention and Mitigation Engineering Research Center of Western Civil Engineering Lanzhou University of TechnologyLanzhou730050China

The accumulation of defects on wind turbine blade surfaces can lead to irreversible damage,impacting the aero-dynamic performance of the *** address the challenge of detecting and quantifying surface defects on wind turbine blades,a blade surface defect detection and quantiﬁcation method based on an improved Deeplabv3+deep learning model is ***,an improved method for wind turbine blade surface defect detection,utilizing Mobilenetv2 as the backbone feature extraction network,is proposed based on an original Deeplabv3+deep learning model to address the issue of limited ***,through integrating the concept of pre-trained weights from transfer learning and implementing a freeze training strategy,signiﬁcant improvements have been made to enhance both the training speed and model training accuracy of this deep learning ***,based on segmented blade surface defect images,a method for quantifying blade defects is *** method combines image stitching algorithms to achieve overall quantiﬁcation and risk assessment of the entire *** results show that the improved Deeplabv3+deep learning model reduces training time by approximately 43.03%compared to the original model,while achieving mAP and MIoU values of 96.87%and 96.93%,***,it demonstrates robustness in detecting different surface defects on blades across different *** application of a blade surface defect quantiﬁcation method enables the precise quantiﬁcation of dif-ferent defects and facilitates the assessment of risk levels associated with defect measurements across the entire *** method enables non-contact,long-distance,high-precision detection and quantiﬁcation of surface defects on the blades,providing a reference for assessing surface defects on wind turbine blades.

关键词： Structural health monitoring computer vision blade surface defects detection Deeplabv3+ deep learning model

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提高肝病学科临床医师的病理修养

临床肝胆病杂志 2018年第11期34卷 2267-2270页

作者：杨永峰南京中医药大学附属南京医院南京市第二医院肝病科南京210003

肝组织病理学检查是肝损伤性疾病病因诊断的重要手段,肝病病理改变表现为"一因多果"和"多因一果",需要临床和病理密切结合才能正确诊断。临床医师掌握肝组织病理的基本知识,不仅可以提高对疾病的认知水平,更有助于在临床病理多学科讨论... 详细信息

肝组织病理学检查是肝损伤性疾病病因诊断的重要手段,肝病病理改变表现为"一因多果"和"多因一果",需要临床和病理密切结合才能正确诊断。临床医师掌握肝组织病理的基本知识,不仅可以提高对疾病的认知水平,更有助于在临床病理多学科讨论中与病理医师更有效的沟通,有条件的医院可遴选基本功扎实的临床医师进修学习肝组织病理学,由临床医师和病理医师共同阅片完成诊断。

关键词：肝疾病病理学诊断述评

Exploring plant adaptation strategies to phosphorus limitation induced by nitrogen addition:foliar phosphorus allocation and root functional traits analysis in two dominant subalpine tree species

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Journal of Plant Ecology 2024年第4期17卷 154-166页

作者： Yan Su yongfeng Tang Yi Hu Meiyu Liu Xuyang Lu Baoli Duan Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Sichuan Ecological Environment Construction Engineering Supervision Co. Ltd.Chengdu 610084China

Plants adapt to the limitation of soil phosphorus(P)induced by nitrogen(N)deposition through a complex interaction of various root and leaf functional *** this study,a pot experiment was conducted to explore the effects of different levels of N addition(control,low N[LN]:25 kg N ha^(-1) yr^(-1),high N[HN]:50 kg N ha^(-1) yr^(-1))on tree growth,leaf nutrient content,foliar P fractions and root characteristics of two dominant tree species,the pioneer species Salix rehderiana Schneid and the climax species Abies fabri(Mast.)Craib,in a subalpine forest in southwestern *** results demonstrated that LN addition had a minimal impact on leaf N and P ***,HN addition significantly decreased the leaf P content in both *** rehderiana exhibited more pronounced increases in specific root length and specific root area under P deficiency triggered by HN addition when compared with *** contrast,*** showed weaker morphological responses to N addition but had a higher proportion of foliar P to metabolic P,as well as higher root exudates rate and root phosphatase activity in response to HN *** fabri employs a synergistic approach by allocating a greater amount of leaf P to metabolite P and extracting P from the soil through P-mobilizing exudates and root phosphatase activity,while *** exhibits higher flexibility in modifying its root morphology in response to P limitation induced by HN *** study provides insights into subalpine tree species adaptation to N-induced P limitation,emphasizing its significance for guiding forest management and conservation in the context of global climate change.

关键词： N deposition root functional traits root morphology root exudation P-scavenging strategy

Microstructure evolution and phase transformation of the mushy zone in a quenchedβ-solidifying TiAl alloy

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Journal of Materials Science & Technology 2024年第2期169卷 28-41页

作者： Fuqiang Zhang Xianfei Ding Leming Xu Xin Feng Hai Nan Jianping He yongfeng Liang Junpin Lin State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Cast Titanium Alloy R&D Center Beijing Institute of Aeronautical MaterialsBeijing 100095China

This study investigates the phase constitutions and transformations that occur in the mushy zone and in the adjacent phase fields of a directionally solidified Ti-44Al-8Nb-1Cr alloy via quenching *** results indicate that the mushy zone consists of unmeltedβdendrites and interdendritic liquid,whose formation can be attributed to the difference in melting point aroused by local heterogeneity in ***βdendrite is composed of numerous subgrains with various *** quenching,theβdendrite transforms into Widmanstättenαvia a precipitation reaction,owing to the decreasing cooling rate caused by heat transfer from the surrounding ***,after quenching,the interdendritic liquid is transformed intoγ*** the singleβphase field and the lower part of the mushy zone,a massive transformation ofβtoγ***,in theβ+αphase field,bothβandαphases are retained to ambient *** the heating process,the transformation ofα→βgives rise to the formation ofβvariants,which affects the orientation ofβdendrites in the mushy *** growth kinematics of theα→βtransformation was elucidated,revealing the preferential growth directions of111and112forβ***,this study presents an illustration of the formation process of the mushy zone and the microstructural evolution during the heating and quenching process.

关键词： Titanium aluminides Mushy zone Quenching Electron backscattering diffraction Phase transformation

社会网络与市场信息对企业战略柔性的驱动机制——基于产品市场类型的差异比较研究

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南开学报（哲学社会科学版） 2015年第4期 87-100页

作者：秦剑杨永峰南开大学国际商务研究所中国科学院前沿科学与教育局

战略柔性对企业获取和保持竞争优势具有重要意义,但现有文献对企业应如何提升战略柔性这一问题存在较大研究空缺。基于访谈和文献分析结果,通过构建战略柔性驱动过程模型,可以考察社会网络和市场信息处理过程及其适配关系对战略柔性的... 详细信息

战略柔性对企业获取和保持竞争优势具有重要意义,但现有文献对企业应如何提升战略柔性这一问题存在较大研究空缺。基于访谈和文献分析结果,通过构建战略柔性驱动过程模型,可以考察社会网络和市场信息处理过程及其适配关系对战略柔性的作用机制,并分析产品市场类型在这一机制中的权变效应。研究发现商业网络促进了战略柔性的提升,且与新兴市场相比,这一效应在成熟市场情境下更为显著,政治网络则对战略柔性具有负向影响。当企业主导产品面向的是成熟市场时,市场信息获取对战略柔性的驱动效应更明显,当企业面向的是新兴市场时,将更多资源用于对所获取信息的消化吸收会对战略柔性的提升产生更大作用。此外,商业网络对市场信息利用的促进作用仅对成熟市场是显著的,而政治网络无论是在市场信息获取还是利用上都要比商业网络发挥更大的效用。总体而言,这一研究结论丰富了战略柔性理论的发展,对我国企业应如何根据不同的产品市场情境来科学构建战略柔性的提升机制也具有重要的管理价值。

关键词：商业网络政治网络信息获取信息利用战略柔性

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高铁网络对重庆市旅游空间结构的影响

地域研究与开发 2018年第4期37卷 104-109页

作者：杜果杨永丰重庆师范大学地理与旅游学院重庆401331

高铁网络带来的时空压缩效应,最直接的影响就是旅游客源地与目的地之间的时间距离缩短,从而引起旅游空间结构变化。以重庆市为研究区域,运用旅游城市吸引力模型和Arc GIS成本距离分析法,通过有高铁网络和无高铁网络两种情况下的对比分析... 详细信息

高铁网络带来的时空压缩效应,最直接的影响就是旅游客源地与目的地之间的时间距离缩短,从而引起旅游空间结构变化。以重庆市为研究区域,运用旅游城市吸引力模型和Arc GIS成本距离分析法,通过有高铁网络和无高铁网络两种情况下的对比分析,结果发现:(1)高铁网络明显提高旅游交通通达性,且高铁连通的区县1h交流圈扩大范围大于没有被高铁连通区域,而原本交通条件较差的区县一日交流圈扩大范围大于原本交通条件较好的区县;(2)高铁开通增强沿线旅游城市吸引力,并强化旅游核心城市的极化和扩散效应;(3)高铁网络加强了区域旅游合作,为重庆市全域旅游发展提供前提和保障,同时也加剧了区域旅游竞争,可能导致旅游业发展水平较低的城市被边缘化现象。在此基础上提出针对性的重庆旅游空间优化建议。

关键词：高铁网络旅游空间结构重庆市

Enhanced reversible hydrogen storage properties of wrinkled graphene microflowers confined LiBH_(4) system with high volumetric hydrogen storage capacity

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Materials Reports(Energy) 2024年第1期4卷 79-88页

作者： Zhenglong Li Kaicheng Xian Hao Chen Mingxia Gao Shanqing Qu Meihong Wu Yaxiong yang Wenping Sun Chao Gao yongfeng Liu Xin Zhang Hongge Pan Institute of Science and Technology for New Energy Xi'an Technological UniversityXi'an710021PR China State Key Laboratory of Silicon and Advanced Semiconductor Materials Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang ProvinceSchool of Materials Science and EngineeringZhejiang UniversityHangzhou310027PR China Department of Polymer Science and Engineering MOE Key Laboratory of Macromolecular Synthesis and FunctionalizationZhejiang UniversityHangzhou310027PR China

LiBH_(4)with high hydrogen storage density,is regarded as one of the most promising hydrogen storage ***,it suffers from high dehydrogenation temperature and poor reversibility for practical *** is effective in achieving low dehydrogenation temperature and favorable ***,graphene can serve as supporting materials for LiBH_(4)catalysts and also destabilize LiBH_(4)via interfacial ***,graphene has never been used alone as a frame material for nanoconfining LiBH_(4).In this study,graphene microflowers with large pore volumes were prepared and used as nanoconfinement framework material for LiBH_(4),and the nanoconfinement effect of graphene was *** loading 70 wt%of LiBH_(4) and mechanically compressed at 350 MPa,8.0 wt% of H2 can be released within 100 min at 320C,corresponding to the highest volumetric hydrogen storage density of 94.9 g H2 L^(-1)ever *** to the nanoconfinement of graphene,the rate-limiting step of dehydrogenation of nanoconfined LiBH_(4) was changed and its apparent activation energy of the dehydrogenation(107.3 kJ mol^(-1))was 42%lower than that of pure LiBH_(4).Moreover,the formation of the intermediate Li_(2)B_(12)H_(12) was effectively inhibited,and the stable nanoconfined structure enhanced the reversibility of LiBH_(4).This work widens the understanding of graphene's nanoconfinement effect and provides new insights for developing high-density hydrogen storage materials.

关键词： Hydrogen storage LiBH_(4) Nanoconfinement Graphene High capacity

Observation of β+-delayed Proton Decay of 69Kr

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IMP & HIRFL Annual Report 1996年 45-46页

作者： Huang Wenxue Xu Xiaoji Ma Ruichang Gu Zhongdao Wang Yanyu yang yongfeng and Dong Chengfu

Ｏｂｓｅｒｖａｔｉｏｎｏｆβ;＋;－ｄｅｌａｙｅｄＰｒｏｔｏｎＤｅｃａｙｏｆ;６９;Ｋｒ￥ＨｕａｎｇＷｅｎｘｕｅ；ＸｕＸｉａｏｊｉ；ＭａＲｕｉｃｈａｎｇ；ＧｕＺｈｏｎｇｄａｏ；ＷａｎｇＹａｎｙｕ；ＹａｎｇＹｏｎｇｆｅｎｇ... 详细信息

Ｏｂｓｅｒｖａｔｉｏｎｏｆβ;＋;－ｄｅｌａｙｅｄＰｒｏｔｏｎＤｅｃａｙｏｆ;６９;Ｋｒ￥ＨｕａｎｇＷｅｎｘｕｅ；ＸｕＸｉａｏｊｉ；ＭａＲｕｉｃｈａｎｇ；ＧｕＺｈｏｎｇｄａｏ；ＷａｎｇＹａｎｙｕ；ＹａｎｇＹｏｎｇｆｅｎｇａｎｄＤｏｎｇＣｈｅｎｇｆｕ;６;?..

关键词： Observation Kr

Targeted anti-cancer therapy: Co-delivery of VEGF siRNA and Phenethyl isothiocyanate (PEITC) via cRGD-modified lipid nanoparticles for enhanced anti-angiogenic efficacy

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Asian Journal of Pharmaceutical Sciences 2024年第2期19卷 170-187页

作者： Bao Li Haoran Niu Xiaoyun Zhao Xiaoyu Huang Yu Ding Ke Dang Tianzhi yang yongfeng Chen Jizhuang Ma Xiaohong Liu Keda Zhang Huichao Xie Pingtian Ding School of Pharmacy Shenyang Pharmaceutical UniversityShenyang 110016China School of Life Science and Biopharmaceutics Shenyang Pharmaceutical University Shenyang 110016 China Department of Basic Pharmaceutical Sciences School of Pharmacy Husson University Bangor ME 04401USA College of Pharmacy Shenzhen Technology UniversityShenzhen 518118China

Anti-tumor angiogenesis therapy, targeting the suppression of blood vessel growth in tumors, presents a potent approach in the battle against cancer. Traditional therapies have primarily concentrated on single-target techniques, with a specific emphasis on targeting the vascular endothelial growth factor, but have not reached ideal therapeutic efficacy. In response to this issue, our study introduced a novel nanoparticle system known as CS-siRNA/PEITC&L-cRGD NPs. These chitosan-based nanoparticles have been recognized for their excellent biocompatibility and ability to deliver genes. To enhance their targeted delivery capability, they were combined with a cyclic RGD peptide (cRGD). Targeted co-delivery of gene and chemotherapeutic agents was achieved through the use of a negatively charged lipid shell and cRGD, which possesses high affinity for integrin αvβ3 overexpressed in tumor cells and neovasculature. In this multifaceted approach, co-delivery of VEGF siRNA and phenethyl isothiocyanate (PEITC) was employed to target both tumor vascular endothelial cells and tumor cells simultaneously. The co-delivery of VEGF siRNA and PEITC could achieve precise silencing of VEGF, inhibit the accumulation of HIF-1α under hypoxic conditions, and induce apoptosis in tumor cells. In summary, we have successfully developed a nanoparticle delivery platform that utilizes a dual mechanism of action of anti-tumor angiogenesis and pro-tumor apoptosis, which provides a robust and potent strategy for the delivery of anti-cancer therapeutics.

关键词： Anti-angiogenesis Tumor apoptosis Nanoparticles VEGF siRNA Hypoxia inducible factor(HIF)-1 protein Phenethyl isothi ocyanate(PEITC)