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大唐不夜城商业步行街空间营造模式研究 被引量:1
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作者 薛璐璐 李凌 +1 位作者 刘伟 高任 《城市建筑》 2023年第3期70-73,99,共5页
商业步行街随着人们生活品质的提高应运而生。各地都建设不同规模的商业步行街,而步行街的空间营造模式成为商业步行街规划能否成功的重要因素之一。研究以西安大唐不夜城商业步行街为例,通过实地调查、访谈分析的方法,从人的使用感受... 商业步行街随着人们生活品质的提高应运而生。各地都建设不同规模的商业步行街,而步行街的空间营造模式成为商业步行街规划能否成功的重要因素之一。研究以西安大唐不夜城商业步行街为例,通过实地调查、访谈分析的方法,从人的使用感受和积极空间与消极空间的角度,对其空间进行研究和评价,并结合景观小品布置,对大唐不夜城的空间营造模式进行分析,获得大唐不夜城商业步行街的优缺点。希望通过此次研究可以为商业步行街的空间营造提供有价值的参考。 展开更多
关键词 商业步行街 大唐不夜城 空间营造 积极空间 消极空间
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高校思政课涵育大学生文化自信探赜 被引量:1
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作者 赵丽媛 翟继军 《黑龙江教育(高教研究与评估)》 2022年第12期84-86,共3页
思想政治理论课对大学生坚定理想信念,提高政治觉悟,提升道德水平,增强爱国情怀和社会责任,涵育文化自信,具有重要作用。高校教育者对教育理念和教学理念的认识之困,思想政治理论课教学方式和教学手段的形式之困,经济全球化带来的整体... 思想政治理论课对大学生坚定理想信念,提高政治觉悟,提升道德水平,增强爱国情怀和社会责任,涵育文化自信,具有重要作用。高校教育者对教育理念和教学理念的认识之困,思想政治理论课教学方式和教学手段的形式之困,经济全球化带来的整体性精神退化和信念障碍的环境之困,是思想政治理论课涵育大学生文化自信不足的现实难题。要通过转变教育教学观念,创新教学方式手段,完善课程体系建设,增进大学生对中国特色社会主义文化的自信。 展开更多
关键词 思想政治理论课 文化自信 大学生
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Risk factors for congenital nasolacrimal duct obstruction in children under two years of age
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作者 Rozhin Kasiri Gholamreza Khataminia +2 位作者 Ali Kasiri Mohammad Sadegh Mirdehghan Mohammad Armin Kasiri 《国际眼科杂志》 CAS 2025年第1期17-23,共7页
·AIM:To identify various risk factors that may play a significant role in the development of congenital nasolacrimal duct obstruction(CNLDO).·METHODS:This observational case-control study included a case gro... ·AIM:To identify various risk factors that may play a significant role in the development of congenital nasolacrimal duct obstruction(CNLDO).·METHODS:This observational case-control study included a case group of 122 children less than two years of age with CNLDO who underwent probing and irrigation treatment at the ophthalmology department of Imam Khomeini Hospital in Ahvaz,Iran,from June 2022 to June2024.A control group of 122 age-matched children without CNLDO was also included for comparison.Data was collected from the children's medical records.·RESULTS:The study found a significant correlation between the occurrence of CNLDO and several maternal factors,such as preeclampsia,the use of levothyroxine,hypothyroidism,having more than three pregnancies(gravidity>3),natural pregnancy,and gestational diabetes mellitus.Additionally,in children,factors,such as oxygen therapy,anemia,reflux,jaundice,and a family history of CNLDO in first-degree relatives were associated with CNLDO,and maternal preeclampsia and hypothyroidism were found to significantly increase the risk of developing CNLDO in children.·CONCLUSION:Given that CNLDO affects both premature and full-term children,the present findings may potentially facilitate the early identification of children and infants at risk of nasolacrimal duct obstruction,thereby preventing the onset of chronic dacryocystitis. 展开更多
关键词 risk factors CONGENITAL nasolacrimal DUCT OBSTRUCTION CHILDREN
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Study of thermal decoherence of harmonic oscillators
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作者 LI Jian ZHOU Gao-Liang +2 位作者 YAN Zheng-Xin LIU Wei WANG Zhao-Qi 《原子与分子物理学报》 CAS 北大核心 2025年第5期108-114,共7页
The thermal decoherence of harmonic oscillators is investigated here.The quantum system presented here is a one-dimensional oscillator with angular frequency,which is surrounded by a thermal bath of environmental osci... The thermal decoherence of harmonic oscillators is investigated here.The quantum system presented here is a one-dimensional oscillator with angular frequency,which is surrounded by a thermal bath of environmental oscillators.There are various environmental oscillators with different angular frequency(below an ultraviolet cutoff).At the beginning,the quantum system is a pure state and the environmental oscillators are in thermodynamic equilibrium with temperature.After a period,the system-environment interactions inspire significant decoherence of the quantum state.Such decoherence is displayed by explicit calculations of the purity and von Neumann entropy of the quantum system.It is worth noting that the decoherence could be significant even in the weak coupling and low temperature case due to the large amount of environmental degrees of freedom.Since the decoherence process is inspired between the quantum system and an ordinary thermal environment here,the thermal decoherence result is quite general. 展开更多
关键词 Quantum decoherence Grand canonical ensemble Oscillators
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Analysis of Chinese Anti-Suit Injunctions in SEP Litigation
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作者 Ou Fuyong Zhang Xiaoxiao 《科技与法律(中英文)》 2025年第1期138-148,共11页
In this article,two cases of Standard Essential Patents,ruled by the Supreme People's Court of the People's Republic of China,are presented and analyzed.The first Chinese anti-suit injunction in SEP litigation... In this article,two cases of Standard Essential Patents,ruled by the Supreme People's Court of the People's Republic of China,are presented and analyzed.The first Chinese anti-suit injunction in SEP litigation appeared in the first case through the method of behavior preservation,and the second case illustrates a clear intent by the Chinese courts to compete for global royalty rate jurisdiction.With international concerns raised about these cases,it is proved that the anti-suit injunction cases in China do not show any abusive or illegal conduct.The worldwide anti-suit injunctions in China are granted legitimately with legal jurisdiction over the cases,sufficient legal grounds for behavior preservation with the nature of anti-suit injunctions,the necessity of granting worldwide injunctions,and suitable granting standards.Several pieces of advice are proposed for the future application of anti-suit injunctions,including improvements in the predictability of validity scope,consistency of implementation,and clarification of penalties. 展开更多
关键词 anti-suit injunction anti-anti-suit injunction FRAND royalty rate JURISDICTION SEP
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Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile
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作者 XU Jian-Qiang MA Zhao-Peng +2 位作者 CHENG Si LIU Zhi-Cong ZHU Guang-Lai 《原子与分子物理学报》 CAS 北大核心 2025年第4期27-32,共6页
The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this wo... The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this work.The following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution function.The results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient decreases.Additionally,the excess molar volume initially decreases,reaches a minimum,and then increases.The rules of radial distribution functions(RDFs)of characteristic atoms are different.With increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then decreases.This indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently. 展开更多
关键词 Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions
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Spraying Arginine at 5 Days before Harvest Delays Postharvest Broccoli Senescence via Nutrient Accumulation
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作者 SUN Yupeng CHEN Ying +4 位作者 SHANG Qingwen GUO Yanyin ZHANG Yuxiao WANG Yunqiao XUE Qingyue 《食品科学》 EI CAS 北大核心 2025年第1期131-141,共11页
To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conduct... To determine the effects of preharvest arginine spraying on the nutritional level of broccoli and the mechanism of action of arginine in improving the storage quality of broccoli,arginine spraying(5 mmol/L)was conducted at 0,1,3,and 5 days before harvest.The appearance,respiration rate,mass-loss rate,electrolyte leakage,glucosinolate,ascorbic acid,total phenol,total flavonoid,total sugar and sucrose contents,and sucrose phosphate synthase(SPS),invertase(INV),sucrose synthase synthesis(SSS)and cleavage(SSC)activities of broccoli samples were observed after 0,2,4,6,8,and 10 days of storage.The results showed that spraying arginine at 5 days preharvest(5-ARG)helped to inhibit broccoli respiration during storage,delay electrolyte leakage,and maintain broccoli color.Furthermore,during the growth stage,total sugar accumulation was higher in the 5-ARG group.In addition,during the storage period,sucrose synthesis was accelerated,while sucrose cleavage was inhibited,resulting in more sucrose retention in postharvest broccoli.In conclusion,5-ARG resulted in the accumulation of more nutrients during the growth process and effectively delayed the quality decline during storage,thereby prolonging the shelf life of broccoli.Therefore,this study provides a theoretical basis for improving postharvest storage characteristics of broccoli through preharvest treatments. 展开更多
关键词 ARGININE BROCCOLI preharvest spraying nutrient accumulation storage quality postharvest senescence
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AAV-mediated expression of p65shRNA and bone morphogenetic protein 4 synergistically enhances chondrocyte regeneration
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作者 Yu Yangyi Song Zhuoyue +2 位作者 Lian Qiang Ding Kang Li Guangheng 《中国组织工程研究》 CAS 北大核心 2025年第17期3537-3547,共11页
BACKGROUND:Adeno-associated virus(AAV)gene therapy has been proven to be reliable and safe for the treatment of osteoarthritis in recent years.However,given the complexity of osteoarthritis pathogenesis,single gene ma... BACKGROUND:Adeno-associated virus(AAV)gene therapy has been proven to be reliable and safe for the treatment of osteoarthritis in recent years.However,given the complexity of osteoarthritis pathogenesis,single gene manipulation for the treatment of osteoarthritis may not produce satisfactory results.Previous studies have shown that nuclear factorκB could promote the inflammatory pathway in osteoarthritic chondrocytes,and bone morphogenetic protein 4(BMP4)could promote cartilage regeneration.OBJECTIVE:To test whether combined application of AAV-p65shRNA and AAV-BMP4 will yield the synergistic effect on chondrocytes regeneration and osteoarthritis treatment.METHODS:Viral particles containing AAV-p65-shRNA and AAV-BMP4 were prepared.Their efficacy in inhibiting inflammation in chondrocytes and promoting chondrogenesis was assessed in vitro and in vivo by transfecting AAV-p65-shRNA or AAV-BMP4 into cells.The experiments were divided into five groups:PBS group;osteoarthritis group;AAV-BMP4 group;AAV-p65shRNA group;and BMP4-p65shRNA 1:1 group.Samples were collected at 4,12,and 24 weeks postoperatively.Tissue staining,including safranin O and Alcian blue,was applied after collecting articular tissue.Then,the optimal ratio between the two types of transfected viral particles was further investigated to improve the chondrogenic potential of mixed cells in vivo.RESULTS AND CONCLUSION:The combined application of AAV-p65shRNA and AAV-BMP4 together showed a synergistic effect on cartilage regeneration and osteoarthritis treatment.Mixed cells transfected with AAV-p65shRNA and AAV-BMP4 at a 1:1 ratio produced the most extracellular matrix synthesis(P<0.05).In vivo results also revealed that the combination of the two viruses had the highest regenerative potential for osteoarthritic cartilage(P<0.05).In the present study,we also discovered that the combined therapy had the maximum effect when the two viruses were administered in equal proportions.Decreasing either p65shRNA or BMP4 transfected cells resulted in less collagen II synthesis.This implies that inhibiting inflammation by p65shRNA and promoting regeneration by BMP4 are equally important for osteoarthritis treatment.These findings provide a new strategy for the treatment of early osteoarthritis by simultaneously inhibiting cartilage inflammation and promoting cartilage repair. 展开更多
关键词 OSTEOARTHRITIS adeno-associated virus bone morphogenetic protein 4 p65-short hairpin RNA gene therapy short hairpin RNA transforming growth factor-β1 extracellular matrix articular cartilage chondrocytes.
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《自动控制原理》微课程建设的思考与实践
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作者 董敏 《智慧工厂》 2024年第4期44-47,共4页
随着信息技术的迅猛发展与教育改革的深入推进,微课程作为一种新兴的教学形式在高等教育中得到了广泛应用。本文围绕《自动控制原理》课程的微课程建设,探讨其必要性、设计思路、实施策略及效果评估,以期为相关课程的微课程开发提供借... 随着信息技术的迅猛发展与教育改革的深入推进,微课程作为一种新兴的教学形式在高等教育中得到了广泛应用。本文围绕《自动控制原理》课程的微课程建设,探讨其必要性、设计思路、实施策略及效果评估,以期为相关课程的微课程开发提供借鉴和参考。 展开更多
关键词 自动控制原理 微课程 教学改革
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浙江省中医院构建中医药特色门诊服务实践及体会
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作者 张莲菁 应京晶 +7 位作者 赵鹏泼 陈岩明 姚斌莲 陈红淑 叶文怡 包文婷 魏澹宁 孙华琴 《中国医院》 北大核心 2024年第9期95-98,共4页
浙江省中医院从中医医院的特殊视角出发,围绕患者就医全流程,以基于提升患者体验构建中医药特色门诊服务为工作目标,推出了“十个一”方案,落实了10项具体举措。以此提升患者门诊体验,取得了丰硕成效,进一步加强了中医医院的中医药人文... 浙江省中医院从中医医院的特殊视角出发,围绕患者就医全流程,以基于提升患者体验构建中医药特色门诊服务为工作目标,推出了“十个一”方案,落实了10项具体举措。以此提升患者门诊体验,取得了丰硕成效,进一步加强了中医医院的中医药人文建设和文化内涵。 展开更多
关键词 中医医院 患者体验 中医药特色 门诊服务
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Improvement of High-Speed Detection Algorithm for Nonwoven Material Defects Based on Machine Vision 被引量:2
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作者 LI Chengzu WEI Kehan +4 位作者 ZHAO Yingbo TIAN Xuehui QIAN Yang ZHANG Lu WANG Rongwu 《Journal of Donghua University(English Edition)》 CAS 2024年第4期416-427,共12页
Defect detection is vital in the nonwoven material industry,ensuring surface quality before producing finished products.Recently,deep learning and computer vision advancements have revolutionized defect detection,maki... Defect detection is vital in the nonwoven material industry,ensuring surface quality before producing finished products.Recently,deep learning and computer vision advancements have revolutionized defect detection,making it a widely adopted approach in various industrial fields.This paper mainly studied the defect detection method for nonwoven materials based on the improved Nano Det-Plus model.Using the constructed samples of defects in nonwoven materials as the research objects,transfer learning experiments were conducted based on the Nano DetPlus object detection framework.Within this framework,the Backbone,path aggregation feature pyramid network(PAFPN)and Head network models were compared and trained through a process of freezing,with the ultimate aim of bolstering the model's feature extraction abilities and elevating detection accuracy.The half-precision quantization method was used to optimize the model after transfer learning experiments,reducing model weights and computational complexity to improve the detection speed.Performance comparisons were conducted between the improved model and the original Nano Det-Plus model,YOLO,SSD and other common industrial defect detection algorithms,validating that the improved methods based on transfer learning and semi-precision quantization enabled the model to meet the practical requirements of industrial production. 展开更多
关键词 defect detection nonwoven materials deep learning object detection algorithm transfer learning halfprecision quantization
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2D S-Scheme Heterojunction Photocatalyst 被引量:2
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作者 Juntao Yan Liang Wei 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第10期1-2,共2页
The application of photocatalytic technology in H_(2) production,CO_(2) reduction,H_(2)O_(2) production,and pollutant degradation provides a promising approach to the alleviation of energy shortage and environmental i... The application of photocatalytic technology in H_(2) production,CO_(2) reduction,H_(2)O_(2) production,and pollutant degradation provides a promising approach to the alleviation of energy shortage and environmental issues 1-3.However,hindered by the easy recombination of electron-hole pairs,single-component photocatalysts usually exhibit inferior performance.Constructing heterojunction photocatalysts is a valid method which can improve charge separation and attain high catalytic efficiencies4. 展开更多
关键词 SEPARATION SHORTAGE POLLUTANT
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Syntheses and catalytic performances of three coordination polymers with tetracarboxylate ligands 被引量:1
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作者 MEI Zhenzhong WANG Hongyu +2 位作者 KANG Xiuqi SHAO Yongliang GU Jinzhong 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1795-1802,共8页
Three zincand cobaltcoordination polymers,namely{[Zn_(2)(μ_(6)-adip)(phen)_(2)]·4H_(2)O}_(n)(1),{[Co_(2)(μ_(6)-adip)(bipy)_(2)]·4H_(2)O}_(n)(2),and[Co_(2)(μ4-adip)(μ-bpa)_(2)]_(n)(3)have been constructed... Three zincand cobaltcoordination polymers,namely{[Zn_(2)(μ_(6)-adip)(phen)_(2)]·4H_(2)O}_(n)(1),{[Co_(2)(μ_(6)-adip)(bipy)_(2)]·4H_(2)O}_(n)(2),and[Co_(2)(μ4-adip)(μ-bpa)_(2)]_(n)(3)have been constructed hydrothermally using H4adip(H4adip=5,5′-azanediyldiisophthalic acid),phen(phen=1,10-phenanthroline),bipy(bipy=2,2′-bipyridine),bpa(bpa=bis(4-pyridyl)amine),and zinc and cobalt chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and single-crystal X-ray diffrac-tion analyses.Single-crystal X-ray diffraction analyses revealed that three compounds crystallize in the orthorhom-bic system Pnna(1 and 2)or P21212(3)space groups.All compounds exhibit 3D frameworks.The catalytic perfor-mances in the Henry reaction of these compounds were investigated.Compound 3 exhibited an effective catalytic activity in the Henry reaction at 70℃.CCDC:2339391,1;2339392,2;2339393,3. 展开更多
关键词 coordination polymer tetracarboxylic acid catalytic properties Henry reaction
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Boehmeria nivea var. strigosa (Urticaceae), a new variety from Southwest China 被引量:1
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作者 ZHAO Ying Richard I.MILNE +2 位作者 LI Zhipeng Amos KIPKOECH WU Zengyuan 《广西植物》 CAS CSCD 北大核心 2024年第9期1617-1624,I0001-I0006,共14页
Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly charact... Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly characterized by its green abaxial leaf blade,partly connate stipules,and densely patent strigose hairs on stems and potioles.The phylogenetic analysis based on rbc L,nrDNA and rbc L+nrDNA datasets,revealed that all individuals of B.nivea var.strigosa formed a monophyletic group.The conservation status of B.nivea var.strigosa is assessed as“Near Threatened”(NT)according to IUCN evaluation criteria.The discovery of this new variety is not only crucial for the taxonomy of ramie,but also provides reference for the exploration and utilization of ramie. 展开更多
关键词 Boehmeria nivea MORPHOLOGY molecular phylogeny new variety Southwest China YUNNAN
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Interfacial Modification of NiO_(x)by Self-assembled Monolayer for Efficient and Stable Inverted Perovskite Solar Cells 被引量:1
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作者 Xin Yu Yandong Wang +5 位作者 Liufei Li Shantao Zhang Shuang Gao Mao Liang Wen-Hua Zhang Shangfeng Yang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第4期553-562,I0080-I0091,I0095,共23页
NiO_(x)as a hole transport material for inverted perovskite solar cells has received great attention owing to its high transparency,low fabrication temperature,and superior stability.However,the mismatched energy leve... NiO_(x)as a hole transport material for inverted perovskite solar cells has received great attention owing to its high transparency,low fabrication temperature,and superior stability.However,the mismatched energy levels and possible redox reactions at the NiO_(x)/perovskite interface severely limit the performance of NiO_(x) based inverted perovskite solar cells.Herein,we introduce a p-type self-assembled monolayer between NiO_(x)and perovskite layers to modify the interface and block the undesirable redox reaction between perovskite and NiO_(x)The selfassembled monolayer molecules all contain phosphoric acid function groups,which can be anchored onto the NiOr surface and passivate the surface defect.Moreover,the introduction of self-assembled monolayers can regulate the energy level structure of NiO_(x),reduce the interfacial band energy offset,and hence promote the hole transport from perovskite to NiO_(x)layer.Consequently,the device performance is significantly enhanced in terms of both power conversion efficiency and stability. 展开更多
关键词 Perovskite solar cell NiO_(x) Self-assembled monolayer Interfacial engineering Stability
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Poly(ethylenimine)-assisted synthesis of hollow carbon spheres comprising multi-sized Ni species for CO_(2) electroreduction
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作者 Kaining Li Yasutaka Kuwahara Hiromi Yamashita 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期66-76,共11页
Electrochemical CO_(2) reduction to produce value-added chemicals and fuels is one of the research hotspots in the field of energy conversion.The development of efficient catalysts with high conductivity and readily a... Electrochemical CO_(2) reduction to produce value-added chemicals and fuels is one of the research hotspots in the field of energy conversion.The development of efficient catalysts with high conductivity and readily accessible active sites for CO_(2) electroreduction remains challenging yet indispensable.In this work,a reliable poly(ethyleneimine)(PEI)-assisted strategy is developed to prepare a hollow carbon nanocomposite comprising a single-site Ni-modified carbon shell and confined Ni nanoparticles(NPs)(denoted as Ni@NHCS),where PEI not only functions as a mediator to induce the highly dispersed growth of Ni NPs within hollow carbon spheres,but also as a nitrogen precursor to construct highly active atomically-dispersed Ni-Nx sites.Benefiting from the unique structural properties of Ni@NHCS,the aggregation and exposure of Ni NPs can be effectively prevented,while the accessibility of abundant catalytically active Ni-Nx sites can be ensured.As a result,Ni@NHCS exhibits a high CO partial current density of 26.9 mA cm^(-2) and a Faradaic efficiency of 93.0% at-1.0 V vs.RHE,outperforming those of its PEI-free analog.Apart from the excellent activity and selectivity,the shell confinement effect of the hollow carbon sphere endows this catalyst with long-term stability.The findings here are anticipated to help understand the structure-activity relationship in Ni-based carbon catalyst systems for electrocatalytic CO_(2) reduction.Furthermore,the PEI-assisted synthetic concept is potentially applicable to the preparation of high-performance metal-based nanoconfined materials tailored for diverse energy conversion applications and beyond. 展开更多
关键词 Hollow carbon sphere Ni nanoparticle CO_(2) reduction Electrocatalysis Single-atom catalyst
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Influence of functionalized graphene on the bacterial and fungal diversity of Vicia faba rhizosphere soil
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作者 CHEN Zhi-wen REN Jing +7 位作者 QIAO Jun ZHAO Jian-guo LI Jing-wei LIU Ze-hui LI Wei-jia XING Bao-yan ZHANG Jin NIE Hui 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第6期1227-1242,共16页
The effect of functionalized graphene on the growth and development of Vicia faba L.was investigated by analyzing its impact on the composition and diversity of the microbial community in rhizosphere peat soil.Seedlin... The effect of functionalized graphene on the growth and development of Vicia faba L.was investigated by analyzing its impact on the composition and diversity of the microbial community in rhizosphere peat soil.Seedlings of V.faba planted in this peat soil were treated with either distilled water(CK)or 25 mg·L^(−1)(G25)of functionalized graphene solution.Results showed that the height and root length of V.faba seedlings in the G25 group were significantly larger than those in CK group.The microbial com-munity was analyzed by amplifying and sequencing the 16S rRNA gene V_(3)-V_(4) region of bacteria and internal transcribed spacer re-gion of fungi in rhizosphere soil using Illumina MiSeq technology.Alpha and beta diversity analysis indicated that functionalized graphene increased the richness and diversity of bacteria and fungi in the V.faba rhizosphere peat soil.The abundances of three ni-trogen cycling-related bacteria,Hydrogenophaga,Sphingomonas and Nitrosomonadaceae,were also altered after treatment with the functionalized graphene.The relative abundance of Basilicum,related to soil phosphorus solubilization,decreased in the fungal com-munity,while the relative abundance of Clonostachys and Dimorphospora,which exhibited strong biological control over numerous fungal plant pathogens,nematodes and insects,increased in the soil after functionalized graphene treatment.Redundancy analysis re-vealed that the potential of hydrogen(pH),organic matter,and total phosphorus contributed the most to the changes in bacterial and fungal community composition in the rhizosphere soil.Overall,our findings suggested that the addition of functionalized graphene altered the relative abundances of nitrogen and phosphorus cycling-related microorganisms in peat soil,promoting changes in the physicochemical properties of the soil and ultimately leading to the improved growth of V.faba plants. 展开更多
关键词 Functionalized graphene Vicia faba L. Plant growth Rhizosphere soil Microbial diversity
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Design and synthesis of two coordination polymers for the rapid detection of ciprofloxacin based on triphenylpolycarboxylic acid ligands
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作者 YANG Dongdong XUE Jianhua +4 位作者 YANG Yuanyu WU Meixia BAI Yujia WANG Zongxuan MA Qi 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第12期2466-2474,共9页
Two coordination polymers were synthesized by hydrothermal reaction,namely,[Cd(H_(3)cpbda)(2,2′‑bipy)(H_(2)O)]_(n)(1)and[Mn(H_(3)cpbda)(phen)(H_(2)O)]_(n)(2),where H_(5)cpbda=5,5′‑[(5‑carboxy‑1,3‑phenyl)bis(oxy)]tri... Two coordination polymers were synthesized by hydrothermal reaction,namely,[Cd(H_(3)cpbda)(2,2′‑bipy)(H_(2)O)]_(n)(1)and[Mn(H_(3)cpbda)(phen)(H_(2)O)]_(n)(2),where H_(5)cpbda=5,5′‑[(5‑carboxy‑1,3‑phenyl)bis(oxy)]triisophthalic acid,2,2′‑bipy=2,2′‑bipyridine,phen=1,10‑phenanthroline.The two complexes were characterized by single‑crystal X‑ray diffraction,powder diffraction,infrared spectroscopy,and thermogravimetric analysis.Complexes 1 and 2 are“V”‑shaped 1D chains,and the molecules form 2D(1)and 3D framework(2)structures through weakπ…πstacking.Furthermore,complex 1 was dispersed in an aqueous solution and its fluorescence intensity demonstrated excellent stability.Complex 1 can specifically detect ciprofloxacin in urine with a detection limit of 1.91×10^(-8)mol·L^(-1).CCDC:2359498,1;2359499,2. 展开更多
关键词 coordination polymer flexible ligand FLUORESCENCE ciprofloxacin detection
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Effects of anions on the structural regulation of Zn‑salen‑modified metal‑organic cage
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作者 GUO Qiaojia CAI Junkai DUAN Chunying 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第11期2203-2211,共9页
By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variationa... By virtue of a 3∶1 complementary coordination strategy,a chiral heteroleptic metal-organic cage that con-tains divergent functional units,Pd‑R(Zn),was precisely constructed via self-assembly of monodentate variational Zn-salen ligands RZn and NADH(reduced nicotinamide adenine dinucleotide)mimic modified tridentate ligands with square-planar Pd ions.UV-Vis and luminescence spectra experiments reveal that different anions could selec-tively interact with different sites of Zn-salen modified metal-organic cages to achieve the structural regulation of cage compound,by using the differentiated host-guest electrostatic interactions of counter ions with metal-organic hosts.Compared to other anions,the presence of chloride ions caused the most significant fluorescence emission enhancement of Pd‑R(Zn),meanwhile,the UV-Vis absorption band attributed to the salen aromatic backbone showed an absorption decrease,and the metal-to-ligand induced peak displayed a blue shift effect.Circular dichro-ism and ^(1)H NMR spectra further demonstrate that the introduction of chloride anions is beneficial to keeping a more rigid scaffold. 展开更多
关键词 metal-organic cage Zn-salen host-guest electrostatic interaction ANIONS structural regulation
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Cryogenic springback of 2219-W aluminum alloy sheet through V-shaped bending
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作者 Xiao-bo FAN Qi-liang WANG +1 位作者 Fang-xing WU Xu-gang WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第10期3185-3193,共9页
A V-shaped bending device was established to evaluate the effects of temperature and bending fillet radius on springback behavior of 2219-W aluminum alloy at cryogenic temperatures.The cryogenic springback mechanism w... A V-shaped bending device was established to evaluate the effects of temperature and bending fillet radius on springback behavior of 2219-W aluminum alloy at cryogenic temperatures.The cryogenic springback mechanism was elucidated through mechanical analyses and numerical simulations.The results indicated that the springback angle at cryogenic temperatures was greater than that at room temperature.The springback angle increased further as the temperature returned to ambient conditions,attributed to the combined effects of the “dual enhancement effect” and thermal expansion.Notably,a critical fillet radius made the springback angle zero for 90° V-shaped bending.The critical fillet radius at cryogenic temperatures was smaller than that at room temperature,owing to the influence of temperature variations on the bending moment ratio between the forward bending section at the fillet and the reverse bending section of the straight arm. 展开更多
关键词 2219-W aluminum alloy cryogenic forming V-shape bending SPRINGBACK critical fillet radius
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