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Germanium-Carbdiyne: A 3D Well-Defined sp-Hybridized Carbon-Based Material with Superhigh Li Storage Property 被引量:1
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作者 Ze Yang Xin Ren +6 位作者 Yuwei Song Xiaodong Li chunfang zhang Xiuli Hu Jianjiang He Jiazhu Li Changshui Huang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第1期199-206,共8页
Carbyne delivers various excellent properties for the existence of the larger number of sp-hybridized carbon atoms.Here,a 3D well-defined porous carbon material germanium-carbdiyne(Ge-CDY)which is comprised of only sp... Carbyne delivers various excellent properties for the existence of the larger number of sp-hybridized carbon atoms.Here,a 3D well-defined porous carbon material germanium-carbdiyne(Ge-CDY)which is comprised of only sp-hybridized carbon atoms bridging by Ge atoms has been developed and investigated.The unique diamond-like structure constructed by linear butadiyne bonds and sp 3-hybridized Ge atoms ensures the stability of Ge-CDY.The large percentage of conjugated alkyne bonds composed of sp-C guarantees the good conductivity and the low band gap,which were further confirmed experimentally and theoretically,endowing Ge-CDY with the potential in electrochemical applications.The well-defined 3D carbon skeleton of Ge-CDY provides abundant uniform nanopores,which is suitable for metal ions storage and diffusion.Further half-cell evaluation also demonstrated Ge-CDY exhibited an excellent performance in lithium storage.All those indicating sp-hybridized carbon-based materials can exhibit great potential to possess excellent properties and be applied in the field of energy,electronic,and so on. 展开更多
关键词 3D porous material electrochemical energy storage germanium-carbdiyne lithium storage theoretical predictions
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Triggering dynamics of acetylene topochemical polymerization 被引量:1
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作者 Xingyu Tang Xiao Dong +3 位作者 chunfang zhang Kuo Li Haiyan Zheng Ho-kwang Mao 《Matter and Radiation at Extremes》 SCIE EI CSCD 2023年第5期82-88,共7页
Topochemical reactions are a promising method to obtain crystalline polymeric materials with distance-determined regio-or stereoselectivity.It has been concluded on an empirical basis that the closest intermolecular C... Topochemical reactions are a promising method to obtain crystalline polymeric materials with distance-determined regio-or stereoselectivity.It has been concluded on an empirical basis that the closest intermolecular C⋅⋅⋅C distance in crystals of alkynes,d(C⋅⋅⋅C)min,should reach a threshold of∼3Åfor bonding to occur at room temperature.To understand this empirical threshold,we study here the polymerization of acetylene in the crystalline state under high pressure by calculating the structural geometry,vibrational modes,and reaction profile.We find d(C⋅⋅⋅C)min to be the sum of an intrinsic threshold of 2.3Åand a thermal displacement of 0.8Å(at room temperature).Molecules at the empirical threshold move via several phonon modes to reach the intrinsic threshold,at which the intermolecular electronic interaction is sharply enhanced and bonding commences.A distance–vibration-based reaction picture is thus demonstrated,which provides a basis for the prediction and design of topochemical reactions,as well as an enhanced understanding of the bonding process in solids. 展开更多
关键词 TEMPERATURE BONDING POLYMERIZATION
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Scaling and clogging treatment of aging tunnel drainage pipes in karst areas using eco-friendly acid agent
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作者 Zhipeng Xu Xuemei Wang +2 位作者 chunfang zhang Dejian Zeng Changwu Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第4期896-910,共15页
In karst areas,the drainage pipes of aging tunnels are prone to be clogged by precipitated carbonates,resulting in lining cracking and tunnel leaking.As a result,not only the driving safety will be deteriorated,but al... In karst areas,the drainage pipes of aging tunnels are prone to be clogged by precipitated carbonates,resulting in lining cracking and tunnel leaking.As a result,not only the driving safety will be deteriorated,but also the water pressure on the lining might also be elevated significantly.For the structural stability and service lifespan of old tunnels,it is of great importance to remove these precipitated carbonates in time.Traditional treatment methods are often destructive to some extent or not efficient enough.This study aims to experimentally develop an eco-friendly acid-based chemical cleaning method to remove carbonate precipitations efficiently.The proposed chemical cleaning agent is an aqueous solution with strong acidity,consisting of sulfamic acid,water,and additives.The factors affecting the cleaning efficiency include the acid solubility,temperature and flow rate of the cleaning agent,as well as additives.Elevating the solution temperature to 50C or a flow rate of no less than 0.2 m/s can improve cleaning efficiency.Although the salt effect cannot work,1 wt%of polymaleic acid as a surfactant could further promote the cleaning rate.The cleaning efficiency will increase with the flow rate in a power function.The relatively low flow rate that improves the cleaning rate considerably can avoid highpressure-induced mechanical damage to tunnel drainpipes.The waste could be easily treated to acceptable levels using commercial sewage treatment products and can also be recycled in agriculture.With the chemical cleaning,the water pressure at the arch springing of the lining will reduce with the increased radius of transverse drainpipes in a power function.The proposed acid-based cleaning method,which is highly efficient,non-or low-destructive to aging tunnels,sufficiently safe for humans,and friendly enough to the environment,will offer a promising alternative to remove the precipitated carbonates in tunnel drainpipes efficiently. 展开更多
关键词 CLOGGING SCALING Carbonate precipitation Acid treatment Water pressure on the lining Aging tunnel KARST
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大学生研究性教学实践——以芳香烃核磁共振的理论计算为例 被引量:1
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作者 张春芳 刘子扬 +5 位作者 赵紫琳 凡绿洁 张攒 商艳丽 霍树营 马刚 《大学化学》 CAS 2022年第12期299-306,共8页
为提高本科生自主学习和探究性学习的能力,指导学生开展了芳香烃体系核磁共振的理论计算研究。在问题引出、文献调研总结、体系建模及模拟、结果分析讨论等研究性教学实践中,学生不仅深入认识了取代基、分子结构、存在状态对化学位移和... 为提高本科生自主学习和探究性学习的能力,指导学生开展了芳香烃体系核磁共振的理论计算研究。在问题引出、文献调研总结、体系建模及模拟、结果分析讨论等研究性教学实践中,学生不仅深入认识了取代基、分子结构、存在状态对化学位移和自旋耦合常数的影响,增进了对微观结构及宏观性质关系的认识,也提高了自主学习、知识应用和解决问题的能力。此外,这种教学活动还提升了学生深入挖掘、不断求证的探究精神和科研素养,有助于创新型人才的培养。 展开更多
关键词 芳香烃 核磁共振 化学位移 研究性教学实践
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Delayed Bleeding of Coronary Artery after Thoracoscopic Intradiaphragmatic Bronchogenic Cyst Resection 被引量:4
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作者 Yuanda CHENG Yang GAO +1 位作者 Abdillah N.JUMA chunfang zhang 《中国肺癌杂志》 CAS CSCD 北大核心 2018年第8期649-651,共3页
Bronchogenic cyst occurring in the diaphragm is rare and thoracoscopic cyst resection is mainly effective treatment. The coronary artery bleeding after video-assisted thoracoscopic surgery(VATS) has never been describ... Bronchogenic cyst occurring in the diaphragm is rare and thoracoscopic cyst resection is mainly effective treatment. The coronary artery bleeding after video-assisted thoracoscopic surgery(VATS) has never been described; here we report a case of left coronary artery injury after thoracoscopic itradiaphragmatic bronchogenic cyst resection, which may be caused by metallic troca or chest tube. 展开更多
关键词 肺癌 患者 临床治疗 放射学治疗
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基于化工卓越人才培养的化工原理实验教学模式改革与探索 被引量:9
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作者 陈鑫 董亮亮 +2 位作者 涂国云 张春芳 白云翔 《大学化学》 CAS 2021年第11期150-154,共5页
卓越工程人才培养是"新工科"建设的核心,针对目前化工原理实验课程教学中出现的问题和不足,江南大学从"新工科"建设视域下,积极探索化工原理实验教学改革,突出教学与育人相结合,为培养科研创新能力强、工程实践能... 卓越工程人才培养是"新工科"建设的核心,针对目前化工原理实验课程教学中出现的问题和不足,江南大学从"新工科"建设视域下,积极探索化工原理实验教学改革,突出教学与育人相结合,为培养科研创新能力强、工程实践能力强、社会责任感强和国际化视野强的"四强"化工卓越人才奠定基础。 展开更多
关键词 新工科 化工原理实验 教学改革 化工卓越人才
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Statistical prediction of failure times under generalized progressive hybrid censoring in a simple step-stress accelerated competing risks model 被引量:2
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作者 chunfang zhang Yimin Shi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第2期282-291,共10页
Based on a simple step-stress accelerated competing risks model from generalized exponential distribution, the statistical prediction problem of unobserved failure times under generalized progressive hybrid censoring ... Based on a simple step-stress accelerated competing risks model from generalized exponential distribution, the statistical prediction problem of unobserved failure times under generalized progressive hybrid censoring is investigated. Using the cumulative exposure model, maximum likelihood predictors, conditional median predictors, approximate prediction intervals and conditional prediction intervals of model parameters and unobserved competing failure times are obtained. To support and illustrate the prediction methods, an available dataset is analyzed and a simulation study is carried out. The numerical results of predictors of model parameters and competing failure times show that the prediction methods have a good performance. © 2017 Beijing Institute of Aerospace Information. 展开更多
关键词 Maximum likelihood Numerical methods Testing
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Solitary AAH Arising from Extralobar Sequestration in A Less Than 3-year-old Boy: A Case Report
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作者 Liqing LU chunfang zhang Yuanda CHENG 《中国肺癌杂志》 CAS CSCD 北大核心 2017年第11期787-788,共2页
We present a case of two-year old boy with solitary atypical adenomatous hyperplasia(AAH)in extralobar sequestration(ELS),which was misdiagnosed as diaphragmatic hernia before surgery.Review of AAH and pulmonary seque... We present a case of two-year old boy with solitary atypical adenomatous hyperplasia(AAH)in extralobar sequestration(ELS),which was misdiagnosed as diaphragmatic hernia before surgery.Review of AAH and pulmonary sequestration(PS)revealed that the present case is the youngest of solitary AAH and also the first report of solitary AAH arising in ELS without a primary lung cancer.In a sense,the present case firstly supports the hypothesis that ELS may be an underlying cancer predisposition syndrome,so aggressive surgical therapy should be recommended for ELS. 展开更多
关键词 非典型腺瘤 患者 治疗方法 临床分析
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围产期紧急子宫切除术后盆腔填纱治疗难治性产后出血的疗效及其影响因素 被引量:6
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作者 周燕媚 孙雯 +7 位作者 林琳 苏春宏 张春芳 余琳 刘娟 王晓怡 贺芳 陈敦金 《中华妇产科杂志》 CAS CSCD 北大核心 2022年第7期504-509,共6页
目的:探讨围产期紧急子宫切除术(EPH)后盆腔填纱控制难治性产后出血的疗效。方法:回顾性分析2014年1月至2021年8月收治的EPH后因手术创面持续出血于外院行盆腔填纱治疗后转诊至广州医科大学附属第三医院,或因EPH后手术创面持续出血转诊... 目的:探讨围产期紧急子宫切除术(EPH)后盆腔填纱控制难治性产后出血的疗效。方法:回顾性分析2014年1月至2021年8月收治的EPH后因手术创面持续出血于外院行盆腔填纱治疗后转诊至广州医科大学附属第三医院,或因EPH后手术创面持续出血转诊至本院后行盆腔填纱治疗,有完整病历资料的11例产妇的临床资料,评估产妇的结局、并发症、住院时间,并分析影响盆腔填纱效果的因素。结果:11例产妇的中位分娩孕周为38.3周(38.0~39.9周),终止妊娠方式为剖宫产术分娩7例(7/11),阴道分娩4例(4/11)。产后出血距盆腔填纱的中位时间为10 h(5~57 h),中位出血量为8 500 ml(4 800~15 600 ml),中位盆腔填纱数量为3块(2~7块),中位纱垫留置时间为6.0 d(3.0~6.0 d)。本次妊娠中位开腹次数为3次(2~3次),最多开腹4次。11例产妇中首次填纱成功止血9例(9/11),最终救治成功11例(11/11)。所有产妇均在实施盆腔填纱前发生失血性休克(11/11)及弥漫性血管内凝血(11/11),其他常见并发症为多器官功能障碍综合征(9/11)、心脏骤停(4/11)、深静脉血栓形成(3/11)、感染性休克(3/11)和肠梗阻(1/11)。所有产妇均于凝血功能恢复且无活动性出血后取出填塞纱垫。11例产妇的中位凝血功能恢复时间为3 d(3~5 d),中位纱垫留置时间6 d(3~6 d),中位重症监护病房住院时间为14 d(11~26 d),中位总住院时间为22 d(16~49 d)。结论:盆腔填纱可以作为EPH后治疗难治性产后出血的临时措施,为生命体征不稳定者争取了损伤控制性复苏的关键时间,为转诊至上一级医疗机构及进一步治疗提供了机会。 展开更多
关键词 子宫切除术 产后出血 止血技术 围产期 妊娠结局
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线性十一并芳烃分子的合成、光物理与自由基性质研究
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作者 李晓慧 张建 +3 位作者 王素娟 邓欣 张春芳 肖金冲 《中国科学:化学》 CAS CSCD 北大核心 2021年第9期1248-1258,共11页
开壳层并苯是一类重要的有机共轭分子,具有独特的物理化学性质,在有机光电转换器件与生物识别检测等领域有广阔的应用前景.本文设计合成了对称引达省([1,2:4,5]二环戊二烯并苯,s-indacene)单元嵌入的十一芳环并合的芳烃分子7a和7b.其最... 开壳层并苯是一类重要的有机共轭分子,具有独特的物理化学性质,在有机光电转换器件与生物识别检测等领域有广阔的应用前景.本文设计合成了对称引达省([1,2:4,5]二环戊二烯并苯,s-indacene)单元嵌入的十一芳环并合的芳烃分子7a和7b.其最大吸收波长分别位于683、678 nm处,与6,8,10,17,19,21-六苯基1.22,4.5,11.12,15.16-四苯并扭曲九并苯(λ_(max)=739 nm)相比,最大吸收波长明显蓝移,表明分子主体骨架上引入的s-indacene在一定程度上影响了分子共轭.研究还表明,与分子7a相比,含有强吸电子基团五氟苯的分子7b具有更好的稳定性.此外,通过近红外紫外可见光谱、电子自旋共振光谱和密度泛函理论计算表明,在7a和7b二氯甲烷溶液中加入六氟碲酸银后,7a和7b均能被氧化成自由基.此外,分子7a和7b在受热后也能呈现明显的电子顺磁信号,证明生成了稳定的自由基. 展开更多
关键词 芳烃 合成 光物理性质 自由基特性
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Inter-phylum negative interactions affect soil bacterial community dynamics and functions during soybean development under long-term nitrogen fertilization 被引量:1
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作者 chunfang zhang Shuo Jiao +1 位作者 Duntao Shu Gehong Wei 《Stress Biology》 CAS 2021年第1期189-201,共13页
Understanding interspecies interactions is essential to predict the response of microbial communities to exogenous perturbation.Herein,rhizospheric and bulk soils were collected from five developmental stages of soybe... Understanding interspecies interactions is essential to predict the response of microbial communities to exogenous perturbation.Herein,rhizospheric and bulk soils were collected from five developmental stages of soybean,which grew in soils receiving 16-year nitrogen inputs.Bacterial communities and functional profiles were examined using high-throughput sequencing and quantitative PCR,respectively.The objective of this study was to identify the key bacterial interactions that influenced community dynamics and functions.We found that the stages of soybean development outcompeted nitrogen fertilization management in shaping bacterial community structure,while fertilization treatments significantly shaped the abundance distribution of nitrogen functional genes.Temporal variations in bacterial abundances increased in bulk soils,especially at the stage of soybean branching,which helps to infer underlying negative interspecies interactions.Members of Cyanobacteria and Actinobacteria actively engaged in inter-phylum negative interactions in bulk soils and soybean rhizosphere,respectively.Furthermore,the negative interactions between nitrogen-fixing functional groups and the reduction of nifH gene abundance were coupled during soybean development,which may help to explain the linkages between population dynamics and functions.Overall,these findings highlight the importance of inter-phylum negative interactions in shaping the correlation patterns of bacterial communities and in determining soil functional potential. 展开更多
关键词 Nitrogen management Soybean development Community spatiotemporal variations Bacterial interactions Functional groups Nitrogen-cycling genes
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