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Novel Synthesis of 2-Amino-3-ethoxycarbonyl Benzopyrans with Onium Salt as Soluble Support

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Chemical Research in Chinese Universities 2011年第3期27卷 435-440页

作者： ZHANG li LU Cui-fen yang Gui-chun CHEN Zu-xing Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules. Faculty of Chemistry and Chemical Engineering Hubei University Wuhan 430062 P. R. China

Task specific onium salt has been presented as soluble support in the synthesis of benzopyrans in this paper. This method allows for results by far superior to those reported other soluble supports and allows for very... 详细信息

关键词： Onium salt Support Benzopyran

Yb^(3+),Tb^(3+)共掺杂Sr_2B_2O_5荧光粉的制备及其下转换发光性能的研究

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无机材料学报 2016年第10期31卷 1081-1086页

作者：戴智刚李友芬李刚杨儒北京化工大学材料电化学过程与技术北京市重点实验室北京100029 北京化工大学碳纤维及功能高分子教育部重点实验室北京100029

采用高温固相法合成了Tb^(3+),Yb^(3+)共掺杂的Sr_2B_2O_5荧光粉。通过X射线衍射(XRD)和荧光光谱(PL)对样品的物相结构和发光性质进行了表征。XRD结果表明,合成样品为单斜结构的Sr_2B_2O_5相。分别使用543 nm和980 nm的监测波长,得到的... 详细信息

采用高温固相法合成了Tb^(3+),Yb^(3+)共掺杂的Sr_2B_2O_5荧光粉。通过X射线衍射(XRD)和荧光光谱(PL)对样品的物相结构和发光性质进行了表征。XRD结果表明,合成样品为单斜结构的Sr_2B_2O_5相。分别使用543 nm和980 nm的监测波长,得到的激发光谱均在354 nm、374 nm处有较强的激发峰,其中374 nm处最强,说明Sr_2B_2O_5荧光材料在近紫外光区对太阳光有很强的吸收;在374 nm(Tb^(3+):~7F_6→~5D_3)紫外光激发下,观察到Tb^(3+):~5D_4→~7F_J(J=6,5,4,3)可见光区发射光,并检测到Yb^(3+):~2F_(5/2)→~2F_(7/2)的近红外发射光。通过研究激发光谱和发射光谱与Yb^(3+)掺杂浓度的关系,发现在单斜晶体Sr_2B_2O_5中,Yb^(3+)具有很高的猝灭浓度。

关键词： Sr2B2O5 Tb^3+ Yb^3+ 下转换发光材料

Micro-strain regulation strategy to stabilize perovskite lattice based on the categories and impact of strain on perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 578-604页

作者： Caixia li Wenwu liu Shiji Da lingbin Kong fen Ran State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology

Photovoltaic metal halide perovskite solar cells(PSCs) convert light to electricity more efficiently than crystalline silicon cells, and the cost of materials used to make them is lower than that of silicon *** efficiency is not a core issue affecting the application of perovskite solar cells in special *** present, stability is the major technical encounters that hinders its further commercial development. Microstrain in PSCs is currently a significant factor responsible for the device's instability. Strain-induced ion migration is widely believed to accelerate perovskite degradation even when external stimuli are ***, it is imperative to study strain to enhance the stability of PSCs. This paper reviews recent developments to understand strain's origin and effect mechanisms on performance of PSCs, including ion migration,failure behavior, defect formation, and its effect on photoelectric properties, stability, and ***, several well-known strain management strategies are systematically introduced based on the strain effect mechanism and strain engineering on the film, providing more clues for further preparation with increased stability. The manipulation of external physical strain applied from films to entire devices has been extensively studied. Furthermore, recommendations for future research directions and chemical approaches have been provided. It is emphasized that strain engineering plays a crucial role in improving the efficiency and longevity of PSCs. Tensile strain causes rapid degradation, while moderate compressive strain and external strain control could improve properties and stability. Efforts should focus on controlling compressive strain to mitigate residual tensile strain and introducing it in a controlled manner. Future research endeavors may focus on exploring these pathways to improve the efficiency and lifespan of PSCs.

关键词： Halide perovskite solar cells Strain origins Strain effects Strain management

Diagnosis of intellectual disability/global developmental delay via genetic analysis in a central region of China

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Chinese Medical Journal 2019年第13期132卷 1533-1540页

作者： li-Hong liao Chen Chen Jing Peng li-Wen Wu Fang He li-fen yang Ci-liu Zhang Guo-li Wang Pan Peng Yu-Ping Ma Pu Miao Fei Yin Department of Pediatrics Xiangya HospitalCentral South UniversityChangshaHunan 410008China Hunan Intellectual and Developmental Disabilities Research Center ChangshaHunan 410008China Department of Pediatrics Zhongnan Hospital of Wuhan UniversityWuhan UniversityWuhanHubei 430071China

Background:Advanced technology has become a valuable tool in etiological studies of intellectual disability/global developmental delay(ID/GDD).The present study investigated the role of genetic analysis to confirm the etiology in ID/GDD patients where the cause of the disease was uncertain in central ***:We evaluated 1051 ID/GDD children aged 6 months to 18 years from March 2009 to April *** concerning basic clinical manifestations were collected,and the method of etiology confirmation was ***-wide copy number variations(CNVs)detection and high-throughput sequencing of exons in the targeted regions was performed to identify genetically-based *** compared the incidence of different methods used to confirm ID/GDD etiology among groups with differing degrees of ID/GDD using the Chi-square or Fisher exact probability ***:We recruited 1051 children with mild(367,34.9%),moderate(301,28.6%),severe(310,29.5%),and profoundly severe(73,6.9%)ID/*** main causes of ID/GDD in the children assessed were perinatal factors,such as acquired brain injury,as well as single gene imbalance and chromosomal gene *** identified karyotype and/or CNVs variation in 46/96(47.9%)of cases in severe ID/GDD patients,which was significantly higher than those with mild and moderate ID/GDD of 34/96(35.4%)and 15/96(15.6%),respectively.A total of 331/536(61.8%)patients with clear etiology have undergone genetic analysis while 262/515(50.9%)patients with unclear etiology have undergone genetic analysis(x^2=12.645,Plinked genes(ATPase copper transporting alpha and bromodomain and WD repeat domain containing 3)and dominant de novo heterozygous mutations i

关键词： Intellectual disability Global developmental delay Children Gene analysis Etiology

Atomically precise nickel-sulfur clusters for efficient electrochemical 2,5-hydroxymethylfurfural oxidation

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Nano Research 2025年第1期18卷 140-148页

作者： fen Wang Lu-Yu liu Sha-Sha Cui Ting-Ting li Xiao-Meng yang Zhijuan liu Yanyong Wang Henan Key Laboratory of Crystalline Molecular Functional Materials Henan International Joint Laboratory of Tumor Theranostical Cluster MaterialsGreen Catalysis Centerand College of ChemistryZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Chem/Bio-sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

Nickel sulfide exhibits excellent catalytic activity in the electrochemical 2,5-hydroxymethylfurfural oxidation reaction(HMFOR).However,due to the polydispersity of nanoparticles,it is difficult to establish a clear structure-activity relationship at the atomic *** this work,we have successfully synthesized atomically precise Ni_(6)(PET)_(12)and Ni_(4)(PET)_(8)clusters(PET:2-phenylethanethiol)for ***^(2+)and S_(2)-with atomic ratio of 1:2 was mainly existed in Ni_(6)(PET)_(12)and Ni_(4)(PET)_(8)to form Ni-S *** electrochemical test results have suggested both Ni_(6)(PET)_(12)and Ni_(4)(PET)_(8)displayed outstanding electrocatalytic ability for *** Ni_(6)(PET)_(12)exhibited better electrocatalytic ability than Ni_(4)(PET)_(8)with higher current density,lower overpotential and faster reaction *** superior electrochemical ability of Ni_(6)(PET)_(12)may be due to the enhanced adsorption towards HMF molecule with strong interaction towards hydroxyl group and furan ***,it found that the Ni^(2+)species in Ni_(6)(PET)_(12)could rapidly oxidized into Ni^(3+)species,which could spontaneously capture electron and proton from HMF for *** theoretical calculation demonstrated that the Ni_(6)(PET)_(12)process lower free energy barrier than Ni_(4)(PET)_(8)to display excellent electrocatalytic *** work is of great significance for designing efficient electrocatalysts for HMFOR.

关键词： atomically precise nickel nanoclusters 2 5-hydroxymethylfurfural electro-oxidation Ni3+species

Increase in the variability of terrestrial carbon uptake in response to enhanced future ENSO modulation

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 32-38页

作者： Younong li li Dan Jing Peng Qidong yang Fuqiang yang Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Key Laboratory of Atmospheric Environment and Processes in the Boundary Layer over the Low-Latitude Plateau Region Department of Atmospheric ScienceYunnan UniversityKunmingChina

El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air *** the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further *** investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 *** results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the *** higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in *** flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through *** occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures.

关键词： Carbon variability ENSO modulation CMIP6 models

PLANTLET REGENERATION FROM PROTOPLASTS ISOLATED FROM CALLUS CULTURES OF IMMATURE INFLORESCENCES OF WHEAT(Triticum aestivum L.)

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Chinese Science Bulletin 1989年第19期34卷 1648-1652页

作者：任延国贾敬芬李名扬郑国锠 Cell Biology Laboratory Lanzhou University Cell Biology Laboratory Lanzhou University Department of Basic Biologysouthwest Agricultural UniversityChomgqingSichuan

Wheat (Triticum aestivum L.) is one of the most important cereal crops in the *** attention has long been paid to the technique of protoplast culture of this *** to now, plantlet regeneration from protoplasts of anther-derived suspension cultures of wheat has been reported for the first time. In the present study, we have obtained numerous embryoids and plantlets from protoplasts of immature inflorescence-derived calli of spring wheat.

关键词： wheat (Triticum aestivum L.) protoplast culture plantlet regeneration

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煤裂解反应红外光谱研究

物理化学学报 1987年第3期3卷 242-247页

作者：王骊冯光瑛杨惠星北京大学化学系北京大学化学系河南师范大学化学系

本文用红外光谱检出了我国河北峰峰煤矿黄沙肥煤中的主要官能团,定量地研究了该煤在裂解过程中主要官能团,OH、CH2、C-O-C、芳香族稠环等的反应动力学。求出各种官的团在不同裂解温度下的反应速率常数、反应级数及表观活化能。

关键词：红外光谱肥煤煤裂解峰峰煤矿 IR 光谱烟煤化学动力学反应动力学官能团裂解反应

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水平井砾石充填数值模拟研究

石油学报 2002年第1期23卷 102-106页

作者：李爱芬杨柳石油大学石油工程系山东东营257062

对于疏松砂岩油藏水平井 ,较好的防砂方法是绕丝筛管砾石充填防砂 ,但目前成功率很低。本文在分析水平井砾石充填过程和充填机理的基础上 ,运用固液两相流理论分析了充填过程中的流动阻力 ,对Gruesbeck提出的模型进行了改进 ,建立了考... 详细信息

对于疏松砂岩油藏水平井 ,较好的防砂方法是绕丝筛管砾石充填防砂 ,但目前成功率很低。本文在分析水平井砾石充填过程和充填机理的基础上 ,运用固液两相流理论分析了充填过程中的流动阻力 ,对Gruesbeck提出的模型进行了改进 ,建立了考虑流体滤失的水平井砾石充填数学模型。通过计算分析了各种因素对充填效率的影响 ,表明 :(1)在一定范围内 ,充填效率随充填排量、携砂液粘度、冲管与筛管直径比的增加而增加 ,但这些数值过大不利于充填成功率的提高。 (2 )充填效率随携砂液中砾石浓度、滤失量及砾石直径的增加而降低。运用此方法可系统优化水平井砾石充填施工参数 ,制定科学合理的施工方案 ,提高防砂成功率。

关键词：油气井水平井砾石充填数值模拟滤失参数优化防砂