Perovskite solar cells(PSCs)are promising in the field of photovoltaics but are hindered by surface defects and stability.However,the energetic losses occurring at the interfaces between the perovskite and the charge ...Perovskite solar cells(PSCs)are promising in the field of photovoltaics but are hindered by surface defects and stability.However,the energetic losses occurring at the interfaces between the perovskite and the charge transport layers often lead to reduced power conversion efficiency(PCE).Surface treatment is an effective strategy but the passivating ligands usually bind with a single active site.The resulted dense packing of resistive passivators perpendicular to the surface is detrimental to charge transport.Here,we present a passivator that can bind to two neighboring lead(Ⅱ)ion(Pb^(2+))defect sites simultaneously with an aligned parallel mode to the perovskite surface,effectively suppressing the surface trap density and preventing the aggregation.The target device fulfills a PCE of 25.1%and maintains over 85% of the initial efficiency after 800 h of exposure to a relative humidity(RH)of 65%±5%.展开更多
A synthetic method of dialkylideneacetones has been developed. Compared with known protocols, the method employed catalytic Ca(OH)_2 as the cheap, mild base catalyst and dilute aqueous EtOH(20%, v/v)as the green and s...A synthetic method of dialkylideneacetones has been developed. Compared with known protocols, the method employed catalytic Ca(OH)_2 as the cheap, mild base catalyst and dilute aqueous EtOH(20%, v/v)as the green and safe solvent. The procedure was easily operated: In most cases, the product could be isolated by a simple filtration, and purified by washing with water. This paper provided experimental details of the reactions, which could be applied in gram-scale synthesis and should be a very reliable and practical protocol to prepare these useful compounds in laboratory and at the industrial level.展开更多
Herein,a series of carbazolyl cyanobenzene(CCB)-based organic photocatalysts with a broad range of photoredox capabilities were designed and synthesized,allowing precise control of the photocatalytic reactivity for th...Herein,a series of carbazolyl cyanobenzene(CCB)-based organic photocatalysts with a broad range of photoredox capabilities were designed and synthesized,allowing precise control of the photocatalytic reactivity for the controllable reduction of aryl halides via a metal-free process.The screened-out CCB(5CzBN),a metal-free,low-cost,scalable and sustainable photocatalyst with both strong oxidative and reductive ability,exhibits superior performance for both dehalogenation and C—C bond-forming arylation reactions.展开更多
With the rapid development of Internet technology and the advent of the era of big data,more and more cyber security texts are provided on the Internet.These texts include not only security concepts,incidents,tools,gu...With the rapid development of Internet technology and the advent of the era of big data,more and more cyber security texts are provided on the Internet.These texts include not only security concepts,incidents,tools,guidelines,and policies,but also risk management approaches,best practices,assurances,technologies,and more.Through the integration of large-scale,heterogeneous,unstructured cyber security information,the identification and classification of cyber security entities can help handle cyber security issues.Due to the complexity and diversity of texts in the cyber security domain,it is difficult to identify security entities in the cyber security domain using the traditional named entity recognition(NER)methods.This paper describes various approaches and techniques for NER in this domain,including the rule-based approach,dictionary-based approach,and machine learning based approach,and discusses the problems faced by NER research in this domain,such as conjunction and disjunction,non-standardized naming convention,abbreviation,and massive nesting.Three future directions of NER in cyber security are proposed:(1)application of unsupervised or semi-supervised technology;(2)development of a more comprehensive cyber security ontology;(3)development of a more comprehensive deep learning model.展开更多
基金supported by the National Key R&D Program of China(2022YFB4200500)the Key Research and Development Plan Project of Anhui Province(2022h11020014)+3 种基金Collaborative Innovation Program of Hefei Science Center,CAS(2022HSCCIP006)the CASHIPS Director’s Fund(YZJJ201902 and YZJJZX202018)the Anhui Provincial Natural Science Foundation(2408085MB029)the Natural Science Foundation of Hebei Province of China(B2024402018)。
文摘Perovskite solar cells(PSCs)are promising in the field of photovoltaics but are hindered by surface defects and stability.However,the energetic losses occurring at the interfaces between the perovskite and the charge transport layers often lead to reduced power conversion efficiency(PCE).Surface treatment is an effective strategy but the passivating ligands usually bind with a single active site.The resulted dense packing of resistive passivators perpendicular to the surface is detrimental to charge transport.Here,we present a passivator that can bind to two neighboring lead(Ⅱ)ion(Pb^(2+))defect sites simultaneously with an aligned parallel mode to the perovskite surface,effectively suppressing the surface trap density and preventing the aggregation.The target device fulfills a PCE of 25.1%and maintains over 85% of the initial efficiency after 800 h of exposure to a relative humidity(RH)of 65%±5%.
基金the National Natural Science Foundation of China (Nos. 21202141, 21672163)Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)+3 种基金Top-notch Academic Programs Project of Jiangsu Higher Education Institutions (TAPP)the high level talent support project of Yangzhou University (top-notch talent, L. Yu)Yangzhou Natural Science Foundation (No. YZ2014040)the Natural Science Foundation of Guangling College (No. ZKZD17005) for financial support
文摘A synthetic method of dialkylideneacetones has been developed. Compared with known protocols, the method employed catalytic Ca(OH)_2 as the cheap, mild base catalyst and dilute aqueous EtOH(20%, v/v)as the green and safe solvent. The procedure was easily operated: In most cases, the product could be isolated by a simple filtration, and purified by washing with water. This paper provided experimental details of the reactions, which could be applied in gram-scale synthesis and should be a very reliable and practical protocol to prepare these useful compounds in laboratory and at the industrial level.
基金the National Natural Scie nce Foundation of China(No.21972094)Guangdong Special Support Program+2 种基金Pengcheng Scholar programShenzhen Peacock Plan(Nos.KQJSCX20170727100802505,KQTD2016053112042971)the Educational Commission of Guangdong Province(No.2016KTSCX126)。
文摘Herein,a series of carbazolyl cyanobenzene(CCB)-based organic photocatalysts with a broad range of photoredox capabilities were designed and synthesized,allowing precise control of the photocatalytic reactivity for the controllable reduction of aryl halides via a metal-free process.The screened-out CCB(5CzBN),a metal-free,low-cost,scalable and sustainable photocatalyst with both strong oxidative and reductive ability,exhibits superior performance for both dehalogenation and C—C bond-forming arylation reactions.
基金the National Natural Science Foundation of China(Nos.61862063,61502413,and 61262025)the National Social Science Foundation of China(No.18BJL104)+2 种基金the Natural Science Foundation of Key Laboratory of Software Engineering of Yunnan Province,China(No.2020SE301)the Yunnan Science and Technology Major Project(Nos.202002AE090010 and 202002AD080002-5)the Data Driven Software Engineering Innovative Research Team Funding of Yunnan Province,China(No.2017HC012)。
文摘With the rapid development of Internet technology and the advent of the era of big data,more and more cyber security texts are provided on the Internet.These texts include not only security concepts,incidents,tools,guidelines,and policies,but also risk management approaches,best practices,assurances,technologies,and more.Through the integration of large-scale,heterogeneous,unstructured cyber security information,the identification and classification of cyber security entities can help handle cyber security issues.Due to the complexity and diversity of texts in the cyber security domain,it is difficult to identify security entities in the cyber security domain using the traditional named entity recognition(NER)methods.This paper describes various approaches and techniques for NER in this domain,including the rule-based approach,dictionary-based approach,and machine learning based approach,and discusses the problems faced by NER research in this domain,such as conjunction and disjunction,non-standardized naming convention,abbreviation,and massive nesting.Three future directions of NER in cyber security are proposed:(1)application of unsupervised or semi-supervised technology;(2)development of a more comprehensive cyber security ontology;(3)development of a more comprehensive deep learning model.
