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聚酰亚胺/钛酸钡复合膜介电性能及其影响因素的研究(Ⅱ)

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功能材料 2008年第2期39卷 264-267页

作者：刘卫东朱宝库谢曙辉徐志康浙江师范大学化学与生命科学学院浙江省固体表面反应化学重点实验室浙江金华321004 浙江大学高分子科学研究所高分子合成与功能构造教育部重点实验室浙江杭州310027

通过前体溶液共混和原位聚合两种方法首先制备聚酰胺酸/BaTiO3前体膜,再经亚胺化得到高介电常数聚酰亚胺/BaTiO3复合膜。考察了不同制备方法、BaTiO3粒子的粒径大小、填充方式等对介电性能的影响。研究发现,通过增加粒子的粒径、使用原... 详细信息

通过前体溶液共混和原位聚合两种方法首先制备聚酰胺酸/BaTiO3前体膜,再经亚胺化得到高介电常数聚酰亚胺/BaTiO3复合膜。考察了不同制备方法、BaTiO3粒子的粒径大小、填充方式等对介电性能的影响。研究发现,通过增加粒子的粒径、使用原位聚合法和采用双模式填充方法都可以有效提高复合膜的介电常数。使用单模式填充方法,由粒径为100nm的改性BaTiO3通过原位聚合法制备得到的复合膜,当BaTiO3的体积分数为0.5时,在10kHz电场中膜的介电常数可以达到45。

关键词：聚酰亚胺钛酸钡复合膜介电性能

Development and prospects of molten steel deoxidation in steelmaking process

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 18-32页

作者： Zhongliang Wang Yanping bao State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

In the long traditional process of steelmaking,excess oxygen is blown into the converter,and alloying elements are used for *** inevitably results in excessive deoxidation of products remaining within the steel liquid,affecting the cleanliness of the *** the increasing requirements for steel performance,reducing the oxygen content in the steel liquid and ensuring its high cleanliness is *** more than a hundred years of development,the total oxygen content in steel has been reduced from approximately 100×10^(-6)to approximately 10×10^(-6),and it can be controlled below 5×10^(-6)in some steel grades.A relatively stable and mature deoxidation technology has been formed,but further reducing the oxygen content in steel is no longer significant for improving steel *** research team developed a deoxidation technology for bearing steel by optimizing the entire conventional *** technology combines silicon–manganese predeoxidation,ladle furnace diffusion deoxidation,and vacuum final *** successfully conducted industrial experiments and produced interstitial-free steel with natural decarbonization ***-aluminum deoxidation was found to control the oxygen content in bearing steel to between 4×10^(-6) and 8×10^(-6),altering the type of inclusions,eliminating large particle Ds-type inclusions,improving the flowability of the steel liquid,and deriving a higher fatigue *** natural decarbonization predeoxidation of interstitial-free steel reduced aluminum consumption and production costs and significantly improved the quality of cast billets.

关键词： steel deoxidation deoxidizer metallurgical equipment bearing steel IF steel

Cooperative enhancement of mechanical and tribological properties through tailoring TiN transition interface in boron nitride nanosheets reinforced copper composites

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Rare Metals 2024年第10期43卷 5202-5215页

作者： Zhong-Hua Li Liang Liu Xin You Jian-Hong Yi Rui bao Ming-Yi zhu Song Lu Jun-Jun Pai Faculty of Materials Science and Engineering Kunming University of Science and Technology Key Laboratory of Advanced Materials of Yunnan Province Kunming University of Science and Technology

Strengthening interface bonding between boron nitride nanosheets(BNNS) and copper matrix is an essential prerequisite for exploiting a new generation of copper matrix composites(CMCs) with high strength and wear resistance. Herein, BNNS/Cu composites were fabricated by the powder metallurgy route, matrix-alloying(adding 1.0 wt% Ti) strategy was adopted to improve the interfacial wettability and strengthen interface adhesion. A typical "sandwich"-like multiply interface structure involving TiN transition layers, BNNS and Cu matrix had been well constructed through the rational heat treatment(900℃for 120 min). Additionally, nano-sized TiB whisker was in situ formed in the vicinity of the interface, it had linked the BNNS-Cu-TiN multiply interface, which played a role of "threading the needle" and significantly strengthened the multi-interfaces bonding. This specific interface structure was finely characterized, and the formation mechanism of solid-state interfacial reaction feature was proposed. The results demonstrated that the ultimate tensile strength(UTS) of BNNS/Cu-(Ti)-900℃ increased from 248 to 530 MPa(increased by 114%), and the coefficient of friction(COF) decreased from 0.51 to 0.28 than pure Cu. This work highlights the importance of interface configuration design, which contributes to the development of CMCs with prominent comprehensive properties.

关键词： Boron nitride nanosheets Copper matrix composites Interface structure Mechanical and frictional properties

Photocatalytic C(sp^(3))-H gem-Difluoroallylation and Alkylation with Alkenes via a Base-Assisted Formal 1,2-Hydrogen Atom Transfer of Amidyl Radicals

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Chinese Journal of Chemistry 2024年第18期42卷 2203-2210页

作者： Meifang Tang Bingbing Feng Yanyang bao Zhongtian Xu Chao Huang Hanliang Zheng Gangguo zhu Yanan Wang Zheliang Yuan Key Laboratory of the Ministry of Education for Advanced Catalysis Materials College of Chemistry and Materials SciencesZhejiangNormalUniversity688YingbinRoadJinhuaZhejiang321004China

Compared to well-established 1,5-HAT of N-centered radicals,the synthetic applications of 1,2-HAT process were scarce due to the high barrier and constrained three-membered transition ***,we have developed a novel C(sp')-H gem-difluoroallylation via a base assisted formal 1,2-HAT of amidyl radicals with the reductive quenching cycle of *** transformation enables the efficient formation ofα-aminoalkyl radicals via 1,2-HAT and showcases good functional group *** preliminary mechanistic experiments,along withDensity Functional Theory(DFT)calculations demonstrate thefeasibility of 1,2-HAT of amidyl radicals,especially when assisted by a ***,our method also succeeds in the Giese addition of electron-deficient alkenes as well as styrene.

关键词： 1,2-Hydrogen atom transfer Amidyl radicals gem-Difluoroallylation Alkenes Photocatalysis Defluoroalkylation

The Sequential Pricing of Ride-Hailing System with Rental Service in the Context of Fleet Electrification

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 77-105页

作者： Yaoyao ku Peng Wu Qiang Ren Yiqing Wang Business School Sichuan UniversityChengdu610065China

Surging demand and reduced capacity in the ride-hailing industry have prompted numerous ride-hailing platforms to build their own car-rental services catering to drivers who do not possess private vehicles. However, the trade-off between the ride-hailing service and the car-rental service is an important issue that is still unclear in theory. Moreover, ride-hailing platforms are transitioning towards all-electric fleets in the context of Carbon Neutrality goals and government regulations. This paper considers a ride-hailing system comprising a monopolist ride-hailing platform, an electric vehicle (EV) rental firm, and a gasoline vehicle (GV) rental firm. Furthermore, we build a stylized model to study the sequential pricing of the system. The equilibrium outcomes show the significant impact of the ride-hailing platform’s decision to continue or withdraw offering EV rental services on EV and GV drivers’ net earnings, rental prices, and wages. The ride-hailing platform providing EV rental services increases EV drivers’ net earnings but decreases the GV driver wages and rental prices. However, the EV rental service offered by the ride-hailing platform does not necessarily lead to an increased total profit for the system. The improved profitability of the system by the ride-hailing platform providing EV rental services is contingent upon lower rider prices and higher fuel costs. The ride-hailing platform’s EV rental services provision also effectively fosters the ride-hailing fleet’s electrification. Furthermore, as the number of riders increases, the ride-hailing platform should reduce the commission rate for EV drivers to maintain competitiveness and profitability.

关键词： Ride-hailing system car rental fleet electrification sequential pricing differential wage scheme

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树状聚合物PAMAM制备高脱盐纳滤膜

功能材料 2011年第5期42卷 793-798页

作者：邓慧宇徐又一朱利平魏秀珍朱宝库浙江大学高分子科学研究所浙江杭州310027 东华理工大学材料科学与工程系江西抚州344000

通过发散法合成了以N-(2-胺乙基)哌嗪为核的端胺基树状聚合物聚酰胺胺(PAMAM),并以此为水相单体与均苯三甲酰氯发生界面聚合反应制备了高脱盐率纳滤膜。采用傅里叶转换红外光谱(FTIR-ATR)、X射线光电子能谱(XPS)等手段研究膜表面化学组... 详细信息

通过发散法合成了以N-(2-胺乙基)哌嗪为核的端胺基树状聚合物聚酰胺胺(PAMAM),并以此为水相单体与均苯三甲酰氯发生界面聚合反应制备了高脱盐率纳滤膜。采用傅里叶转换红外光谱(FTIR-ATR)、X射线光电子能谱(XPS)等手段研究膜表面化学组成的变化,扫描电镜(SEM),原子力显微镜(AFM)观察膜的结构与形貌,接触角测定仪评价膜的亲水性。结果表明,使用高代数PAMAM、增大PAM-AM浓度、延长反应时间均促使膜的致密度增加,脱盐率增大。使用浓度为4.46×10-3 mol/L第二代PAM-AM溶液为反应物制备的纳滤膜对Na2SO4、MgCl2、MgSO4的脱除率分别达到93.0%,92.3%和91.4%。值得注意的是,PAMAM浓度的增加导致酰氯基由过量到相对不足,最终所制备的纳滤膜对NaCl、Na2SO4、MgCl2和MgSO4等4种盐的脱盐顺序也发生相应变化,主要体现在MgCl2的脱除率由低于Na2SO4和MgSO4变化到高于这两种盐最后三者的脱除率趋于近似相等,均>90%。

关键词：树状聚合物PAMAM 界面聚合高脱盐纳滤膜

The actin motor protein OsMYA1 associates with OsExo70H1 and contributes to rice secretory defense by modulating OsSyp121 distribution

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Journal of Integrative Plant Biology 2024年第9期66卷 2058-2075页

作者： Yuan‐bao Li Chengyu Liu Ningning Shen Shuai zhu Xianya Deng Zixuan Liu Li‐Bo Han Dingzhong Tang State Key Laboratory of Ecological Control of Fujian‐Taiwan Crop Pests Key Laboratory of Ministry of Education for GeneticsBreeding and Multiple Utilization of CropsPlant Immunity CenterFujian Agriculture and Forestry UniversityFuzhou 350002China College of Agriculture Fujian Agriculture and Forestry UniversityFuzhou 350002China College of Life Sciences Fujian Agriculture and Forestry UniversityFuzhou 350002China School of Future Technology Fujian Agriculture and Forestry UniversityFuzhou 350002China

Magnaporthe oryzae(***)is a devastating hemibiotrophic *** biotrophic invasive hyphae(IH)are enclosed in the extrainvasive hyphal membrane produced by plant cells,thus generating a front line of the battlefield between the pathogen and the host *** plants,defense-related complexes such as proteins,callose-rich materials and vesicles,are directionally secreted to this interface to confer defense responses,but the underlying molecular mechanism is poorly *** this study,we found that a Myosin gene,Myosin A1(OsMYA1),contributed to rice *** OsMYA1 knockout mutant exhibited decreased resistance to *** ***1 localizes to the actin cytoskeleton and surrounds the IH of ***1 interacts with an exocyst subunit,OsExo70H1,and regulates its accumulation at the plasma membrane(PM)and pathogen–plant ***,OsExo70H1 interacted with the rice syntaxin of the plants121 protein(OsSyp121),and the distribution of OsSyp121 to the PM or the pathogen–plant interface was disrupted in both the OsMYA1 and OsExo70H1 ***,these results not only reveal a new function of OsMYA1 in rice blast resistance,but also uncover a molecular mechanism by which plants regulate defense against *** by OsMYA1-initiated vesicle secretory pathway,which originates from the actin cytoskeleton to the PM.

关键词： cytoskeleton plant defense mechanism rice blast vesicle delivery

Telomere-to-telomere genome assemblies of two Chinese Baijiu-brewing sorghum landraces

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Plant Communications 2024年第6期5卷 9-12页

作者： Jiandong bao Heng Zhang Fulin Wang Lin Li Xueming zhu Junfeng Xu Yao Wang Zhijian Liu Guowei Zhai Heng Xu Fucheng Lin Ying zhu State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products Zhejiang Academy of Agricultural SciencesHangzhou 310021ZhejiangChina Institute of Plant Protection and Microbiology Zhejiang Academy of Agricultural SciencesHangzhou 310021China Institute of Virology and Biotechnology Zhejiang Academy of Agricultural SciencesHangzhou 310021China College of Advances Agricultural Science Zhejiang A&F UniversityHangzhou 311300ZhejiangChin

Dear Editor,Sorghum(Sorghum bicolor[L.]Moench)(2n=20),a C4 droughttolerant cereal crop,is widely cultivated for food,feed,and biofuel,resulting in varieties with distinct morphological *** Sanger-sequencing-based sorghum reference genome of the inbred variety BTx623(grain sorghum)was initially released in 2009(base error<1 per 10 kb)(Paterson et al.,2009),and the most widely used version 3 assembly(base error<1 per 100 kb),consisting of 4773 contigs with 2679 unresolved gaps(~28 Mb)in 10 chromosomes,was improved by next-generation sequencing in 2017(McCormick et al.,2018).

关键词： Sorghum cultivated cereal

原子转移自由基聚合与高分子膜亲水化/功能化构造

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功能材料 2009年第2期40卷 181-184页

作者：易砖徐又一朱利平董汉棒朱宝库浙江大学材料与化学工程学院高分子科学研究所教育部水处理中心浙江杭州310027

原子转移自由基聚合(ATRP)对膜的亲水化/功能化改性包括对膜基体材料的共聚改性和对膜的表面改性。膜基体材料的改性最多见于PVDF为主链的两亲性聚合物。ATRP对膜的表面改性尤其是膜的表面引发方法,可实现将不同功能性单体接枝到聚合物... 详细信息

原子转移自由基聚合(ATRP)对膜的亲水化/功能化改性包括对膜基体材料的共聚改性和对膜的表面改性。膜基体材料的改性最多见于PVDF为主链的两亲性聚合物。ATRP对膜的表面改性尤其是膜的表面引发方法,可实现将不同功能性单体接枝到聚合物膜表面,得到了抗污染能力强,生物相容性好,开关响应迅速等多种功能性表面层。直接的表面引发改性是一种高效,灵活的表面修饰/功能化方法,也是目前应用最广泛的改性技术。

关键词：原子转移自由基聚合表面引发改性功能化