检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

4H-SiC晶片热导率的激光拉曼光谱研究

太原科技大学学报 2024年第2期45卷 187-192页

作者：任春辉郭之健张宇飞王凯悦太原科技大学材料科学与工程学院太原030024

在本研究中,使用激光激发的激光拉曼光谱研究了4H-SiC晶片从低温(80 K)到室温(290 K)的热导率。在整个测量过程中,激光既作为拉曼光谱的激发源又作为热源,通过激光加热提高了晶片表面的局部温度。同样,拉曼峰的位置会随着晶片温度的升... 详细信息

在本研究中,使用激光激发的激光拉曼光谱研究了4H-SiC晶片从低温(80 K)到室温(290 K)的热导率。在整个测量过程中,激光既作为拉曼光谱的激发源又作为热源,通过激光加热提高了晶片表面的局部温度。同样,拉曼峰的位置会随着晶片温度的升高而向高频侧偏移,通过分析拉曼光谱位置的偏移和局部温度升高的关系得到了4H-SiC晶片的热导率。结果表明,4H-SiC晶片的热导率在低温情况下随温度升高而升高,此时K∝T 3,当热导率的值达到最大后随着温度的升高而降低,此时K∝T-1,这归因于声子-声子间相互作用和声子缺陷散射的作用。

关键词： 4H-SiC 热导率拉曼光谱低温

Integrating microRNAs and mRNAs reveals the hormones synthesis and signal transduction of maize under different N rates

在线全文

学校读者我要写书评

暂无评论

农业科学学报:英文版 2023年第9期22卷 2673-2686页

作者： yue kai LI Ling-ling XIE Jun-hong Zechariah EFFAH Sumera ANWAR WANG Lin-lin MENG Hao-feng LI Lin-zhi College of Agronomy Gansu Agricultural UniversityLanzhou 730070P.R.China State Key Laboratory of Aridland Crop Science Gansu Agricultural UniversityLanzhou 730070P.R.China Council for Scientific and Industrial Research Plant Genetic Resources Research InstituteBunso 00233Ghana Department of Biosciences Durham UniversityDurham DH13LEUK Department of Botany Government CollegeWomen UniversityFaisalabad 38000Pakistan College of Resources and Environment Science Gansu Agricultural UniversityLanzhou 730070P.R.China

The effect of nitrogen(N)fertilizer on the development of maize kernels has yet to be fully ***-mRNA analyses could help advance our understanding of how kernels respond to *** study analyzed the morphological,physiological,and transcriptomic changes in maize kernels under different N rates(0,100,200,and 300 kg ha–1).The result showed that increasing N application significantly increased maize grains’fresh and dry weight until N reached 200 kg ha–*** levels of indole-3-acetic acid,cytokinin,gibberellin,and a lower level of ethylene were associated with increased N *** obtained 31 differentially expressed genes(DEGs)in hormone synthesis and transduction,and 9 DEGs were regulated by 14 differentially expressed microRNAs(DEMIs)in 26 *** candidate DEGs and DEMIs provide valuable insight for manipulating grain filling under different N rates.

关键词： maize kernels phytohormones high-throughput sequencing microRNA

MicroRNA-15a-cell division cycle 42 signaling pathway in pathogenesis of pediatric inflammatory bowel disease

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2018年第46期24卷 5234-5245页

作者： Wen-Juan Tang kai-yue Peng Zi-Fei Tang Yu-Huan Wang Ai-Juan Xue Ying Huang Department of Gastroenterology Children’s Hospital of Fudan University

AIM To determine whether cell division cycle(Cdc)42 is regulated by microRNA(miR)-15 a in the development of pediatric inflammatory bowel disease(IBD).METHODS We cultured 293 T cells, used plasmids and performed dual-luciferase assay to determine whether Cdc42 is a miR-15 a target gene. We cultured Caco-2 cells, and stimulated them with tumor necrosis factor(TNF)-α. We then employed lentiviruses to alter the expression of miR-15 a and Cdc42. We performed quantitative reverse transcription polymerase chain reaction(qRTPCR) and immunofluorescence to determine whether Cdc42 is regulated by miR-15 a in Caco-2 cells. Finally, we collected ileocecal tissue by endoscopy from patients and performed qRT-PCR to examine the expression of miR-15 a and Cdc42 in pediatric IBD *** Target Scan and dual-luciferase assay revealed thatCdc42 was a miR-15 a target gene. MiR-15 a expression increased(P = 0.0038) and Cdc42 expression decreased(P = 0.0013) in cells stimulated with TNF-α, and the expression of the epithelial junction proteins zona occludens(ZO)-1(P < 0.05) and E-cadherin(P < 0.001) decreased. Cdc42 levels decreased in miR-15 a-mimic cells(P < 0.001) and increased in miR-15 a inhibitor cells(P < 0.05). ZO-1 and E-cadherin decreased in mi R-15 a-mimic cells(P < 0.001) but not in the miR-15 a inhibitor + TNF-α cells. In Lv-Cdc42 + TNF-α cells, ZO-1 and E-cadherin expression increased compared to the Lv-Cdc42-NC + TNF-α(P < 0.05) or miR-15 a-mimic cells(P < 0.05). Fifty-four pediatric IBD patients were included in this study, 21 in the control group, 19 in the Crohn's disease(CD) active(AC) group, seven in the CD remission(RE) group, and seven in the ulcerative colitis(UC) group. MiR-15 a increased and Cdc42 decreased in the CD AC group compared to the control group(P < 0.05). miR-15 a decreased and Cdc42 increased in the CD RE group compared to the CD AC group(P < 0.05). miR-15 a was positively correlated with the Pediatric Crohn's disease Activity Index(PCDAI)(P

关键词： Pediatric inflammatory bowel disease MicroRNA-15a Cell division cycle 42 Zona occludens-1 E-cadherin

Highly Red Emissive Conjugated Homopolymers Based on Double B←N Bridged Bipyridine Unit

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第8期42卷 1029-1037页

作者： Yu-yue Gao kai-Yuan Zhang Shu-Meng Wang Hui Tong Jun Liu State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Conjugated homopolymers based on six-member rings,e.g.,polyfluorene,always exhibit blue emission and conjugated homopolymers based on five-member rings,e.g.,polythiophene,can give red emission with low *** this work,we report a series of new conjugated homopolymers based on six-member rings with high-efficiency deep-red *** repeating units of the red light emitting homopolymers are double B←N bridged bipyridine(BNBP)with the boron atoms functionalized with diphenyl,borafluorene,and 2,7-di-tert-butyl-borafluorene groups,*** relationship between the chemical structures and the opto-electronic properties of the monomers and the homopolymers has been systematically *** three polymers emit pure red light(λ_(max)=656 nm)or deep red light(λ_(max)=693 nm)with fluorescence quantum efficiency in solution higher than 60%.The polymers can be used as the emitters in solution-processed organic light-emitting diodes with red emission and decent device *** work indicates a new strategy to design highly efficient light emitting conjugated polymers.

关键词： Conjugated homopolymers Double B←N bridged bipyridine(BNBP) Deep-red emission High fluorescent efficiency

Quantum Spin Exchange Interactions to Accelerate the Redox Kinetics in Li–S Batteries

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2024年第5期16卷 370-383页

作者： Yu Du Weijie Chen Yu Wang yue Yu kai Guo Gan Qu Jianan Zhang Key Laboratory of Advanced Energy Catalytic and Functional Materials Preparation of Zhengzhou City College of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001People’s Republic of China

Spin-engineering with electrocatalysts have been exploited to suppress the“shuttle effect”in Li–S *** selec-tion,spin-dependent electron mobility and spin potentials in activation barriers can be optimized as quantum spin exchange interactions lead-ing to a significant reduction of the electronic repulsions in the orbitals of ***,we anchor the MgPc molecules on fluorinated carbon nanotubes(MgPc@FCNT),which exhibits the single active Mg sites with axial *** to the density functional theory calculations,the electronic spin polarization in MgPc@FCNT not only increases the adsorption energy toward LiPSs intermediates but also facilitates the tunneling process of electron in Li–S *** a result,the MgPc@FCNT provides an initial capacity of 6.1 mAh cm^(-2) even when the high sulfur loading is 4.5 mg cm^(-2),and still maintains 5.1 mAh cm^(-2) after 100 *** work provides a new perspective to extend the main group single-atom catalysts enabling high-performance Li–S batteries.

关键词： Metal phthalocyanines Spin polarization Electrocatalysis Li–S batteries

High-temperature oxidation resistance of Si-coated C/SiC composites

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第9期43卷 4566-4572页

作者： Jie Xiao Hua-yue Zhang Sheng-kai Gong Hui-Bin Xu Hong-Bo Guo School of Materials Science and Engineering Beihang University Key Laboratory of High-Temperature Structure Materials and Protective Coatings (Ministry of Industry and Information Technology) Beihang University

In this paper, Si coatings were sprayed onto C/Si C composite substrates by atmospheric plasma spraying(APS). The high-temperature oxidation behavior of the substrate and coating at temperatures of 1100 and 1300 °C was also studied. The C/Si C ceramic matrix composite will be damaged seriously and even failed due to the oxidation of carbon fibers in matrix. The Si coating effectively improved the oxidation resistance of the C/Si C substrate in the high-temperature oxidation test. The effect of the thickness of the Si coatings on the oxidation resistance was investigated. The 150-μm coating is proved to enable the substrate to have the lowest oxidation weight loss and the best oxidation resistance after static oxidation for 5 h.

关键词： Carbon fiber Ceramic matrix composites (CMCs) Oxidation Plasma spray Si coating

油田环保安全标准内容智能推荐发展方向与对策建议

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

标准科学 2024年第3期 88-92页

作者：黄珊王凯月延伟孙红军刘佳王美中国石油化工股份有限公司胜利油田分公司技术检测中心中国标准化研究院胜利油田检测评价研究有限公司

油田环保安全标准内容智能推荐系统对于提升油田行业标准工作和应用效率具有重大意义。本文聚焦于油田环保安全标准内容智能推荐系统的发展方向与建议研究,厘清了油田环保安全标准体系的构成,明确了油田环保安全标准内容智能推荐的概念... 详细信息

油田环保安全标准内容智能推荐系统对于提升油田行业标准工作和应用效率具有重大意义。本文聚焦于油田环保安全标准内容智能推荐系统的发展方向与建议研究,厘清了油田环保安全标准体系的构成,明确了油田环保安全标准内容智能推荐的概念内涵和主要内容,研判了油田环保安全标准内容智能推荐的发展方向,在此基础上,提出了促进油田环保安全标准内容智能推荐技术和系统发展的对策建议。

关键词：油田环保安全领域标准内容智能推荐发展方向对策建议

Polyoxometalates-derived nanostructures for electrocatalysis application

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第5期43卷 1845-1866页

作者： Chao-yue Sun Wen Li kai Wang Wei-Jia Zhou Hai-Qing Wang Institute for Advanced Interdisciplinary Research(iAIR) College of Chemistry and Chemical EngineeringUniversity of JinanJinan250022China Shandong Electrical Engineering and Equipment Group Intelligent Electric Co. Ltd.Jinan 250022China

The conversion of intermittent renewable electrical energy to chemical energy is of great importance which can not only mitigate current energy and environmental crisis but also contribute to the ongoing carbon neutrality national *** is serving as a low-carbon conversion technology that enables green and efficient energy conversion mainly through hydrogen evolution reaction(HER),carbon dioxide reduction reaction(CO_(2)RR),and nitrogen reduction reaction(NRR).The core of electrocatalysis is the design and construction of low-cost high-activity and high-stability electrocatalyst to drive reaction thermodynamics and *** employment of polyoxometalates(POMs)as platforms or precursors to construct different types of electrocatalysts has been widely ***,we systematically summarized the recent advances in POM-derived nanostructures for electrocatalysis *** strategies for precursor design and electrocatalyst synthesis were briefly *** morphology control,phase control,composite modulation,and heterostructure engineering in POM-derived nanostructures were presented in *** structure–activity relationship of POM-derived nanostructures is fully discussed for HER CO_(2)RR,and NRR ***,the current challenges and future outlooks of POM-derived nanostructures are summarized to provide insights toward high-efficiency electrocatalysts for energy conversion technologies.

关键词： Microforming Cylindrical compression Size effects Grain orientation Inhomogeneous deformation

杀菌与苗龄协同作用对岩黄连假植苗成活率和生长势的影响

在线全文

学校读者我要写书评

暂无评论

贵州农业科学 2024年第7期52卷 81-89页

作者：马永鹏龙云星权申春王茜岳凯高朝文刘元剑昭通市农业科学院云南昭通657000

【目的】探明岩黄连假植过程中杀菌与苗龄协同作用对其成活率和生长的影响,为岩黄连高效假植生产提供理论依据。【方法】以岩黄连幼苗为试验材料,研究杀菌与不同假植苗龄(真叶数2片、3片、4片、5片和6片)对黄连假植苗成活率和生长势的... 详细信息

【目的】探明岩黄连假植过程中杀菌与苗龄协同作用对其成活率和生长的影响,为岩黄连高效假植生产提供理论依据。【方法】以岩黄连幼苗为试验材料,研究杀菌与不同假植苗龄(真叶数2片、3片、4片、5片和6片)对黄连假植苗成活率和生长势的影响。【结果】各苗龄试验组杀菌处理较未杀菌处理的假植苗成活率显著(P<0.05)提高7.10~42.75百分点,平均提高26.07百分点;是否杀菌处理对相同苗龄假植苗各生长指标的影响差异均不显著。真叶数与假植苗成活率呈显著正相关,幼苗真叶数为3~6片且经杀菌处理黄连假植苗的死苗率≤10%;杀菌处理下苗龄(真叶数)与假植苗的根重(0.63)、根粗(0.73)、叶绿素相对含量(0.55)和地上部分重量(0.69)呈显著正相关,适宜生长的真叶数为3~6片。通过全株相对生长势指数(RGI)分析,真叶数与岩黄连假植苗全株RGI呈显著正相关,进一步确定岩黄连幼苗最适宜假植苗龄为4片真叶期。【结论】4片真叶期岩黄连假植苗经杀菌处理后的成活率和生长最佳。

关键词：岩黄连假植杀菌苗龄成活率生长势