检索结果-南通市图书馆

molecular packing tuning via chlorinated end group enables efficient binary organic solar cells over 18.5%

Carbon Energy 2024年第3期6卷 196-203页

作者： Yafeng Li Zhenyu Chen Xingzheng Yan Ziyi ge Zhejiang Business Technology Institute NingboZhejiangChina Zhejiang Engineering Research Center for Energy Optoelectronic materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingboZhejiangChina Center of materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingChina

Designing novel nonfullerene acceptors(nFAs)is of vital importance for the development of organic solar cells(OSC).modification on the side chain and end group are two powerful tools to construct efficient ***,based on the high-performance L8BO,we selected 3-ethylheptyl to substitute the inner chain of 2-ethylhexyl,obtaining the backbone of *** we introduced different halogen atoms of fluorine and chlorine on 2-(3-oxo-2,3-dihydro-1Hinden-1-ylidene)malononitrile end group(EG)to construct efficient nFAs named BOn3-F and BOn3-Cl,*** donor D18 was chosen to combine with two novel nFAs to construct OSC ***,D18:BOn3-Cl-based device shows a remarkable power conversion efficiency(PCE)of 18.57%,with a high open-circuit voltage(V_(OC))of 0.907 V and an excellent fill factor(FF)of 80.44%,which is one of the highest binary PCE of devices based on D18 as the ***,BOn3-F-based device shows a relatively lower PCE of 17.79%with a decreased FF of 79.05%.The better photovoltaic performance is mainly attributed to the red-shifted absorption,higher electron and hole mobilities,reduced charge recombination,and enhanced molecular packing in the D18:BOn3-Cl ***,we performed stability tests on two binary systems;the D18:BOn3-Cl and D18:BOn3-F devices maintain 88.1%and 85.5%of their initial efficiencies after 169 h of storage at 85°C in an n2-filled glove box,*** work demonstrates the importance of selecting halogen atoms on EG and provides an efficient binary system of D18:BOn3-Cl for further improvement of PCE.

关键词： binary organic solar cell chlorinated end group molecular packing

来源：

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

Cobalt(Ⅲ)hydride HAT mediated enantioselective intramolecular hydroamination access to chiral pyrrolidines

引用

Science China Chemistry 2024年第6期67卷 2002-2008页

作者： Qi meng Tao Qin Huanran miao ge Zhang Qian Zhang Jilin Province Key Laboratory of Organic Functional molecular Design&Synthesis Department of ChemistryNortheast Normal UniversityChangchun130024China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Enantioenriched pyrrolidines and derivatives are ubiquitous substructures in compounds of importance to medicinal and biological ***,we report an efficient cobalt-catalyzed intramolecular asymmetric hydroamination reaction that produces chiral pyrrolidines with good to excellent yield and *** with previously reported radicalinvolved methodologies for enantioenriched pyrrolidines,these conditions feature two elegant versatilities,enabling(1)the use of cobalt-catalyzed hydrogen atom transfer(HAT)to generate organocobalt intermediates that bring radical reaction to organometallic chemistry,and(2)enantioselective intramolecular C-n bond forging through an S_(n)2-like displacement involving dynamic kinetic resolution(DKR).This approach provides a new alternative and efficient methodology for enantioselective radical-involved C-n bond construction that can be used in the synthesis of both chiral pyrrolidines and homologous nitrogen heterocycles.

关键词： asymmetric catalysis radical hydroamination cobalt catalysis hydrogen atom transfer

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Tetraphenylethene-based hole transporting material for highly efficient and stable perovskite solar cells

引用

Science China Chemistry 2024年第6期67卷 2009-2015页

作者： Peng Wang Pei Yuan Chenghao ge Rongjun Zhao Lin Xie Yong Hua School of materials and Energy Yunnan UniversityKunming650091China

2,2,7,7-Tetrakis-(n,n-di-p-methoxyphenylamine)-9,9-spirobifluorene(Spiro-OmeTAD)has been identified as the most widely used and effective hole transporting material(HTm)in perovskite solar cells(PSCs).However,the complicated multistep synthesis and low intrinsic hole mobility of Spiro-Ome TAD limit its commercialized ***,developing highly efficient HTms with less synthetic steps becomes increasingly ***,understanding hot carriers transfer dynamics at the interface of perovskite layer and hole transport layer is crucial for further enhancing PSCs performance towards Shockley-Queisser limit,which still lacks full investigation to ***,a new HTm based on tetraphenylethene(WP1)was successfully synthesized by a simple one-step reaction *** was found that WP1-based HTm exhibits more matched energy level,higher hole mobility and conductivity than those of the control Spiro-Ome *** femtosecond transient absorption results reveal that the transfer rate of hot holes in perovskite/WP1 sample is four times higher than that of perovskite/Spiro-OmeTAD,thereby helping enhance the device ***,the efficiency of PSCs is enhanced to 24.04%(WP1)from 22.85%(Spiro-OmeTAD).moreover,the un-encapsulated device prepared with WP1 exhibits better long-term stability,retaining 87%of its initial PCE value after storing for 72 days under air environment,while the reference device shows76%of its initial *** work indicates that simple tetraphenylethene-based organic small molecule could be a very promising HTm candidate for highly efficient PSCs,and gives some significant insights for understanding intrinsic hot carriers transfer dynamics in device.

关键词： tetraphenylethene hole transporting material perovskite solar cells mobility hot carrier

来源：

维普期刊数据库

同方期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

multiplicity of solutions for the semilinear subelliptic Dirichlet problem

引用

Science China mathematics 2024年第3期67卷 475-504页

作者： Hua Chen Hong-ge Chen Jin-ning Li Xin Liao School of mathematics and Statistics Wuhan UniversityWuhan 430072China Wuhan Institute of Physics and mathematics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China

In this paper,we study the semilinear subelliptic equation{−△Xu=f(x,u)+g(x,u)inΩ,u=0 on∂Ω,where△X=−∑m i=1 Xi∗Xi is the self-adjoint Hormander operator associated with the vector fields X=(X_(1),X_(2),...,X_(m))satisfying the Hormander's condition,f(x,u)∈C(Ω×R),g(x,u)is a Carathéodory function onΩ×R,andΩis an open bounded domain in R~n with smooth *** the perturbation from the symmetry method with the approaches involving the eigenvalue estimate and the morse index in estimating the minimax values,we obtain two kinds of existence results for multiple weak solutions to the problem ***,we discuss the difference between the eigenvalue estimate approach and the morse index approach in degenerate *** with the classical elliptic cases,both approaches here have their own strengths in the degenerate *** new phenomenon implies that the results in general degenerate cases would be quite different from the situations in classical elliptic cases.

关键词： degenerate elliptic equations Hormander operators perturbation method morse index

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A hybrid data-mining framework for train rescheduling strategy pattern discovery

引用

Transportation Safety and Environment 2024年第1期6卷 56-67页

作者： Ruirui Chen Xuekai ge Ping Huang Chao Wen School of Transportation&Logistics Southwest Jiaotong UniversityChengdu 611756China Department of IT Operational Technology CN RailWaterloo N2V2R1Canada

This study presents a hybrid data-mining framework based on feature selection algorithms and clustering methods to perform the pattern discovery of high-speed railway train rescheduling strategies(RSs).The proposed model is composed of two *** the first state,decision tree,random forest,gradient boosting decision tree(GBDT)and extreme gradient boosting(XGBoost)models are used to investigate the importance of *** features that have a high influence on RSs are first *** the second state,a K-means clustering method is used to uncover the interdependences between RSs and the influencing features,based on the results in the first *** proposed method can determine the quantitative relationships between RSs and influencing *** results clearly show the influences of the factors on RSs,the possibilities of different train operation RSs under different situations,as well as some key time periods and key trains that the controllers should pay more attention *** research in this paper can help train traffic controllers better understand the train operation patterns and provides direction for optimizing rail traffic RSs.

关键词： high-speed railway rescheduling strategy pattern discovery feature identification clustering algorithm

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Facile access to C-n bonds via unexpected side reactions of Knoevenagel condensation and their application in high-efficiency organic solar cells

引用

Science China Chemistry 2024年第1期67卷 323-329页

作者： Daobin Yang Shuncheng Yang Hongqian Wang Lin Xie Pengyu Yan Ziyi ge Zhejiang Engineering Research Center for Energy Optoelectronic materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China School of materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China Center of materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The construction of C-n bonds is of great importance in the fields of biology,medicine,chemistry and materials ***,the replacement of organic base from pyridine to piperidine in the Knoevenagel condensation process unexpectedly yields a series of novel organic molecules containing C-n ***,the synthesis method does not require any external transition-metals catalysis,and photo-/***,when the new compound 1b is added as a third component to a well-known binary system of Pm6:Y6,the efficiency of the organic solar cell is significantly improved,resulting in an outstanding efficiency of 18.0%,which is one of the highest values reported to date for Pm6:Y6-based ternary organic solar cells.

关键词： C-n bonds Knoevenagel condensation cross-coupling reaction third component organic solar cells

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Cu single atoms embedded on hollow g-C_(3)n_(4)nanospheres with enhanced charge transfer and separation for efficient photocatalysis

引用

Chinese Chemical Letters 2024年第2期35卷 455-459页

作者： Linlin Zhang Jianjun Liao Yakun Li Wei Sun Chengjun ge Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province School of Ecology and EnvironmentHainan UniversityHaikou 570228China Shandong Ocean Chemical Industry Scientific Research Institute Weifang 262737China

Establishing an effective charge transfer mechanism in carbon nitride(g-C_(3)n_(4))to enhance its photocatalytic activity remains a limiting ***,the combination design of a single Cu atom with hollow g-C_(3)n_(4)nanospheres(Cu-n_(3)structure)has been proven to offer significant opportunities for this crucial ***,this structure endows two pathways for charge transfer in the reaction,namely,the n atoms in the three-dimensional planar structure are only bonded with a single Cu atom,and charge transfer occurs between the plane and the layered structure due to the bending of the interlayered g-C_(3)n_(4)hollow ***,Cu-n_(3)and hollow nanosphere structures have been certified to greatly enhance the efficiency of photogenerated carrier separation and transfer between the layers and planes by ultrafast spectral *** a result,this catalyst possesses unparalleled photocatalytic ***,the hydrogen production rate up to 2040μmol h^(−1) g^(−1),which is 51 times that of pure C_(3)n_(4)under visible light *** photocatalytic degradation performance of tetracycline and oxidation performance of benzene is also expressed,with a degradation rate of 100%,a conversion of 97.3%and a selectivity of 99.9%.This work focuses on the structure-activity relationship to provide the possibilities for the development of potential photocatalytic materials.

关键词： g-C_(3)n_(4) Cu single atom Hollow nanospheres Charge transfer pathways Photocatalytic hydrogen production

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Potassium alleviated high nitrogen-induced apple growth inhibition by regulating photosynthetic nitrogen allocation and enhancing nitrogen utilization capacity

引用

Horticultural Plant Journal 2024年第1期10卷 1-14页

作者： Xinxiang Xu Guangyuan Liu Jingquan Liu mengxue Lyu Fen Wang Yue Xing Hao meng min Li Yu Jiang ge Tian Zhanling Zhu Yuanmao Jiang Shunfeng ge State Key Laboratory of Crop Biology College of Horticulture Science and EngineeringShandong Agricultural UniversityTai'anShandong 271018China Key Laboratory of Biochemistry and molecular Biology in Universities of Shandong College of Biological and Agricultural EngineeringWeifang UniversityWeifangShandong 261061China

There is a close relationship between potassium(K)and nitrogen(n).However,the roles of K under high n conditions remain *** a hydroponics approach,we monitored the morphological,physiological,and molecular changes in m9T337 apple(malus domestica)rootstocks under different nitrate(10 and 30 mmol·L^(-1)nO_(3)^(-))and K supply(0.5,6,10,and 20 mmol·L_(-1)K^(+))*** revealed that high nitrate inhibited the root growth of m9T337 rootstocks,downregulated the expressions of K transporter genes(mdPT5,mdHKT1,and mdATK1),and reduced the net nO3-and K+influx at the surface of roots,thereby resulting in an n/K imbalance in *** investigation showed that 10 mmol·L^(-1)K increased the activity of n metabolic enzymes(nR,GS,niR,and GOGAT),upregulated the expressions of genes related to nitrate uptake and transport(mdnRT1.1,mdnRT1.2,mdnRT1.5,and mdnRT2.4),promoted15n transport from the roots to the shoots,optimized leaf n distribution,and improved photosynthetic n utilization efficiency under high nitrate *** results suggest that the negative effects of high nitrate may be related to the n/K imbalance and that reducing n/K in plants by increasing K supply level can effectively alleviate the inhibition of n assimilation by high nitrate stress.

关键词： Apple rootstock K level High nitrate stress n metabolism ^(15)n

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Single‑cell sequencing reveals the reproductive variations between primiparous and multiparous Hu ewes

引用

Journal of Animal Science and Biotechnology 2024年第2期15卷 614-631页

作者： Ting ge Yifan Wen Bo Li Xiaoyu Huang Shaohua Jiang Enping Zhang Key Laboratory of Animal genetics Breeding and Reproduction of Shaanxi ProvinceCollege of Animal Science and TechnologyNorthwest A&F UniversityYangling 712100China

Background In the modern sheep production systems,the reproductive performance of ewes determines the economic profitability of *** the genetic mechanisms underlying differences in the litter size is important for the selection and breeding of highly prolific *** sheep,a high-quality Chinese sheep breed,is known for its high fecundity and is often used as a model to study prolificacy *** the current study,animals were divided into two groups according to their delivery rates in three consecutive lambing seasons(namely,the high and low reproductive groups with≥3 lambs and one lamb per season,n=3,respectively).The ewes were slaughtered within 12 h of estrus,and unilateral ovarian tissues were collected and analyzed by 10×genomics single-cell RnA *** A total of 5 types of somatic cells were identified and corresponding expression profiles were mapped in the ovaries of each ***,the differences in the ovary somatic cell expression profiles between the high and low reproductive groups were mainly clustered in the granulosa ***,four granulosa cell subtypes were *** analysis revealed that the abundance of JPH1 expression and the reduction of LOC101112291 expression could lead to different evolutionary directions of the granulosa ***,the expression levels of FTH1 and FTL in mural granulosa cells of the highly reproductive group were significantly *** genes inhibit necroptosis and ferroptosis of mural granulosa cells,which helps prevent follicular *** This study provides insights into the molecular mechanisms underlying the high fecundity of Hu *** differences in gene expression profiles,particularly in the granulosa cells,suggest that these cells play a critical role in female *** findings also highlight the importance of genes such as JPH1,LOC101112291,FTH1,and FTL in regulating granulosa cell function and follicular development.

关键词： Granulosa cells Hu sheep Lambing number Ovarian somatic cells Single-cell RnA sequencing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Knockout of a rice K5.2 gene increases Ca accumulation in the grain

引用

Journal of Integrative Plant Biology 2024年第2期66卷 252-264页

作者： Peitong Wang naoki Yamaji namiki mitani-Ueno Jun ge Jian Feng ma national Key Laboratory of Crop genetics&germplasm Enhancement and Utilization College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China Institute of Plant Science and Resources Okayama UniversityKurashiki 710-0046Japan

Rice is a staple food for half of the world’s population,but it is a poor dietary source of calcium(Ca)due to the low *** is an important issue to boost Ca concentration in this grain to improve Ca deficiency risk,but the mechanisms underlying Ca accumulation are poorly ***,we obtained a rice(Oryza sativa)mutant with high shoot Ca *** mutant exhibited 26%-53% higher Ca in shoots than did wild-type rice(WT)at different Ca *** concentration in the xylem sap was 36% higher in the mutant than in the *** was no difference in agronomic traits between the WT and mutant,but the mutant showed 25% higher Ca in the polished grain compared with the ***-based cloning combined with a complementation test revealed that the mutant phenotype was caused by an 18-bp deletion of a gene,OsK5.2,belonging to the Shaker-like K+channel ***5.2 was highly expressed in the mature region of the roots and its expression in the roots was not affected by Ca levels,but upregulated by low *** showed that OsK5.2 was mainly expressed in the pericycle of the *** together,our results revealed a novel role for OsK5.2 in Ca translocation in rice,and will be a good target for Ca biofortification in rice.

关键词： accumulation biofortification calcium OsK5.2 pericycle rice translocation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：