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Selective Recognition and Detection of L-Aspartic Acid by Molecularly Imprinted Polymer in Aqueous Solution
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作者 Nazia Tarannum Meenakshi Singh 《American Journal of Analytical Chemistry》 2011年第8期909-918,共10页
Molecularly imprinted polymers selective for L-aspartic acid (LAA) have been prepared using the carboxy-betaine polymer bearing zwitterionic centres along the backbone. LAA is well known to promote good me-tabolism, t... Molecularly imprinted polymers selective for L-aspartic acid (LAA) have been prepared using the carboxy-betaine polymer bearing zwitterionic centres along the backbone. LAA is well known to promote good me-tabolism, treat fatigue and depression along with its significance in accurate age estimation in the field of forensic science and is an important constituent of ‘aspartame’, the low calorie sweetener. In order to study the intermolecular interactions in the prepolymerization mixture between the monomer and the template (LAA)/non-template (DAA), a computational approach was developed. It was based on the binding energy of the complex between the template and functional monomer. The results demonstrate that electrostatic in-teractions primarily guide the imprinting protocol. The MIP was able to selectively and specifically take up LAA from aqueous solution, human blood serum and certain pharmaceutical samples quantitatively. Hence, a facile, specific and selective technique to detect the amino acid, LAA in the presence of various interfer-rants, in different kinds of matrices is presented. 展开更多
关键词 AMINO ACID l-aspartic ACID Molecularly Imprinted polyMER (MIP) Computational Modeling Carboxybetaine polyMER SELECTIVE Recognition
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Synthesis of L-Aspartic Acid and Lactone Copolymers
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作者 Ren Xi ZHUO Jie CHENG(Department of Chemistry, Laboratory of Biomedical Polymer Materials of the State EducationCommission of China, Wuhan University, Wuhan 430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第5期443-445,共3页
Biodegradable poly(alc-alt-Asp) was synthesized by ring-opening polymerization of the monomer 3-(S)-[(benzyloxycarbonyl)methyl] -morpholine-2, 5-dione and subsequent catalytic hydrogenation. Copolymers of the monomer ... Biodegradable poly(alc-alt-Asp) was synthesized by ring-opening polymerization of the monomer 3-(S)-[(benzyloxycarbonyl)methyl] -morpholine-2, 5-dione and subsequent catalytic hydrogenation. Copolymers of the monomer with glycolide, D,L-lactide and L-lactide were also prepared. 展开更多
关键词 polydepsipeptide ring-opening polymerization l-aspartic acid GLYCOLIDE LACTIDE
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Synthesis,Characterization and Antibacterial Properties of Rare Earth (Ce^(3+) ,Pr^(3+) ,Nd^(3+) ,Sm^(3+) ,Er^(3+) ) Complexes with L-Aspartic Acid and o-Phenanthroline 被引量:15
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作者 郁慧 何其庄 +1 位作者 杨静 郑文捷 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z2期4-8,共5页
Five novel ternary complexes of rare earth ions with L-Aspartic acid (Asp) and o-phenanthroline (Phen) were synthesized in ethanol aqueous solution. Their compositions were characterized by elemental analysis, molar c... Five novel ternary complexes of rare earth ions with L-Aspartic acid (Asp) and o-phenanthroline (Phen) were synthesized in ethanol aqueous solution. Their compositions were characterized by elemental analysis, molar conductance, FT-IR, Raman, UV-VIS and TG-DTA. The compositions of the complexes were confirmed to be: RE( Asp)3PhenCl3·3H2O (RE: Ce3+ , Pr3+ , Nd3+ , Sm3+ , Er3+ ). The antibacterial activity test shows that all these complexes exhibit excellent antibacterial ability against Escherichia coli, Staphylococcus aureus and Candida albicans. The antimicrobial spectrum of the complexes are broad. 展开更多
关键词 COMPLEXES O-PHENANTHROLINE l-aspartic acid antibacterial activity rare earths
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4天香烟烟雾暴露联合poly(I:C)刺激对小鼠肺部免疫应答及干扰素表达的影响
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作者 董晓飞 梁紫尧 +5 位作者 范龙 全景羽 林琳 周颖芳 吴蕾 于旭华 《中国免疫学杂志》 CAS CSCD 北大核心 2024年第1期67-71,共5页
目的:探讨短期香烟烟雾暴露联合poly(I:C)刺激对小鼠肺部免疫应答及干扰素表达的影响。方法:BALB/c小鼠随机分为4组:对照组、熏烟组、poly(I:C)组和熏烟联合poly(I:C)组。检测支气管肺泡灌洗液(BALF)中总细胞数及细胞分类计数;普通光镜... 目的:探讨短期香烟烟雾暴露联合poly(I:C)刺激对小鼠肺部免疫应答及干扰素表达的影响。方法:BALB/c小鼠随机分为4组:对照组、熏烟组、poly(I:C)组和熏烟联合poly(I:C)组。检测支气管肺泡灌洗液(BALF)中总细胞数及细胞分类计数;普通光镜下观察各组细胞形态;荧光定量PCR检测肺组织细胞因子、趋化因子和干扰素及干扰素刺激基因表达。结果:与对照组相比,熏烟联合poly(I:C)组总细胞数计数、巨噬细胞与中性粒细胞计数明显升高(P<0.05),且熏烟联合poly(I:C)组巨噬细胞计数高于poly(I:C)组;与poly(I:C)组比较,熏烟联合poly(I:C)组小鼠气道灌洗液巨噬细胞体积较大,呈圆形或不规则形,细胞质较多空泡;与对照组相比,熏烟联合poly(I:C)组小鼠肺组织中性粒细胞趋化因子CXCL1(P<0.05)、CXCL2(P<0.01)和淋巴细胞趋化因子CCL2(P<0.01)mRNA表达升高,肺组织IL-1β、IL-6、TNF-αmRNA表达明显升高(P<0.01),肺组织IFN-β(P<0.01)、IFN-γ(P<0.05)、MX2(P<0.01)和IP-10(P<0.01)表达显著升高,且与poly(I:C)组小鼠相比,熏烟联合poly(I:C)组小鼠肺组织CXCL2(P<0.05)、TNF-α(P<0.01)和IFN-β(P<0.05)mRNA表达明显升高。结论:熏烟联合poly(I:C)诱导了小鼠肺部炎症反应和干扰素及干扰素刺激基因表达。同时,香烟暴露加剧了poly(I:C)诱导的小鼠肺部急性炎症反应和Ⅰ型干扰素表达。 展开更多
关键词 香烟烟雾 poly(I:C) 免疫细胞 气道炎症 干扰素
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Electrocatalytic oxidation and determination of dopamine at a carbon ionic liquid electrode modified with nafion-L-aspartic acid composite film
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作者 Xiao-Dong Shangguan,Jian-Bin Zheng,Qing-Lin Sheng,Ya-Ping He Institute of Analytical Science,Shaanxi Provincial Key Laboratory of Electroanalytical Chemistry,Northwest University,Xi’an 710069,China 《Journal of Pharmaceutical Analysis》 SCIE CAS 2010年第1期1-6,共6页
The electrocatalytic oxidation of dopamine(DA)was studied by electrochemical approaches at a carbon ionic liquid electrode(CILE)modified with the composite film of nafion and L-aspartic acid(NL-CILE).The CILE was fabr... The electrocatalytic oxidation of dopamine(DA)was studied by electrochemical approaches at a carbon ionic liquid electrode(CILE)modified with the composite film of nafion and L-aspartic acid(NL-CILE).The CILE was fabricated by replacing non-conductive organic binders with a room-temperature hydrophobic ionic liquid,1-butyl-3-methyl-imidazolium hexafluorophosphate.The composite film of NL was used as matrix to adsorb DA and catalyze the oxidation of DA in phosphate buffer solution(PBS).The electrochemical response of DA was investigated at the NL-CILE,the traditional carbon paste electrode(TCPE),CILE and the nafion modified CILE(N-CILE)in 0.1M PBS(pH 7.4),respectively.The results showed the superiority of NL-CILE to N-CILE,CILE and TCPE in terms of provision of higher sensitivity,faster electron transfer and better reversibility.Under optimum condition,the oxidation peak current was rectilinear with DA concentration range from 0.1μM to 0.1mM,with a detection limit of 0.03μM(S/N=3)by differential pulse voltammetry.The proposed method was applied to determine DA in samples successfully. 展开更多
关键词 VOLTAMMETRY Ionic liquid NAFION l-aspartic acid DOPAMINE
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Preparation and enantiosorption of L-aspartic acid pillared hydrotalcites
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作者 彭霞辉 黄可龙 《Journal of Central South University of Technology》 EI 2007年第4期520-523,共4页
L-aspartic acid (Asp) pillared hydrotalcites were prepared by direct reaction of the L-Asp anion with layered double hydroxides (LDHs). The obtained samples were characterized by X-ray diffractometry (XRD), Four... L-aspartic acid (Asp) pillared hydrotalcites were prepared by direct reaction of the L-Asp anion with layered double hydroxides (LDHs). The obtained samples were characterized by X-ray diffractometry (XRD), Fourier transform infrared (FTIR), and thermogravimetric and differential thermal analysis (TG/DTA). The results show that the initial interlayer carbonate ions can be completely replaced by the L-Asp anion under the controlled conditions. The pillared hydrotalcites have a crystallized supramolecular structure and thermal stability. The L-Asp pillared LDHs were used in the enantiosorption of enantiopure phenylalanine (Pile), the results suggest that L-Asp pillared LDHs exhibit an excellent enantiosorption capability for D-Phe, and the adsorption isotherm fits Freundlich equation. 展开更多
关键词 l-aspartic acid HYDROTALCITES PREPARATION enantiosorption PHENYLALANINE
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Synthesis and Crystal Structure of a New Ternary Complex of Nickel(II) with L-Aspartic Acid and 1,10-Phenanthroline
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作者 马录芳 梁福沛 +2 位作者 覃海错 胡瑞祥 张漫波 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第12期1376-1382,共7页
A new ternary complex of nickel(II) with L-aspartate (L-Asp) and 1, 10-phenan- throline(Phen), [Ni3(L-Asp)(Phen)5(H2O)3](ClO4)4?4.75H2O, has been synthesized in a mixed sol- vent of H2OC2H5OH at the pH value of 3. I... A new ternary complex of nickel(II) with L-aspartate (L-Asp) and 1, 10-phenan- throline(Phen), [Ni3(L-Asp)(Phen)5(H2O)3](ClO4)4?4.75H2O, has been synthesized in a mixed sol- vent of H2OC2H5OH at the pH value of 3. It crystallizes in triclinic, space group P1 with a = 11.861(2), b = 18.384(4), c = 19.746(3) ?, α = 107.68(1), β = 105.94(1), γ = 103.41(2)°, V = 3703.6(11) ?3, Mr = 1745.66, Z = 2, Dc =1.565 g/cm3, μ = 0.989 mm-1, F(000) = 1791, R = 0.0643 and wR = 0.1611. The complex contains two cations, binuclear [Ni2(L-Asp)(Phen)3(H2O)]2+ and mononu- clear [Ni(Phen)2(H2O)2]2+. All the nickel ions in the complex are six-coordinated with a distorted octahedral geometry, but the coordination environments for them are different. There exist hydrogen bonds and π-π stacking interactions in the complex. 展开更多
关键词 l-aspartic acid 1 10-PHENANTHROLINE nickel(II) complex crystal structure
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Investigation on interaction of L-aspartic acid with Vctoria Green S and its application
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作者 LU Li-yuan ZHAO Dan-hua ZI Yan-qin 《Journal of Chemistry and Chemical Engineering》 2008年第6期38-43,51,共7页
The interaction of L-Aspartic acid (Asp) with Vctoria Green S (VGS) in pH 6.0 Britton-Robinson buffer solution has been investigated by UV/Vis spectropbotometry and resonance light scattering (RLS) technique. Th... The interaction of L-Aspartic acid (Asp) with Vctoria Green S (VGS) in pH 6.0 Britton-Robinson buffer solution has been investigated by UV/Vis spectropbotometry and resonance light scattering (RLS) technique. The non-covalent interactions such as hydrogen bond, salt linkage and hydrophobic bond were proposed to explain the interaction between VGS and Asp. It indicated that Asp could link each other to form a long chain by salt linkages and hydrogen bonds in aqueous medium. Then the long chain surrounded the hydrophobic groups of VGS via hydrophobic interaction and reacted with VGS by salt linkages and hydrogen bonds to form a macromolecular aggregation. The aggregation was much bigger than VGS itself. So the color became deeper and the system's absorption and RLS intensity increased. The increase in the absorbance at 617nm was proportional to the concentration of Asp, providing a basis for the quantitative determination of Asp. This method was simple and efficient than the ordinary methods and had been applied to the direct determination of Asp with satisfactory results. 展开更多
关键词 l-aspartic acid Vctoria Green S SPECTROPHOTOMETRY resonance light scattering non-covalent bond
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Stable Cycling of All-Solid-State Lithium Metal Batteries Enabled by Salt Engineering of PEO-Based Polymer Electrolytes 被引量:1
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作者 Lujuan Liu Tong Wang +6 位作者 Li Sun Tinglu Song Hao Yan Chunli Li Daobin Mu Jincheng Zheng Yang Dai 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期67-74,共8页
Poly(ethylene oxide)(PEO)-based polymer electrolytes show the prospect in all-solid-state lithium metal batteries;however,they present limitations of low room-temperature ionic conductivity,and interfacial incompatibi... Poly(ethylene oxide)(PEO)-based polymer electrolytes show the prospect in all-solid-state lithium metal batteries;however,they present limitations of low room-temperature ionic conductivity,and interfacial incompatibility with high voltage cathodes.Therefore,a salt engineering of 1,1,2,2,3,3-hexafluoropropane-1,3-disulfonimide lithium salt(LiHFDF)/LiTFSI system was developed in PEO-based electrolyte,demonstrating to effectively regulate Li ion transport and improve the interfacial stability under high voltage.We show,by manipulating the interaction between PEO matrix and TFSI^(-)-HFDF^(-),the optimized solid-state polymer electrolyte achieves maximum Li+conduction of 1.24×10^(-4)S cm^(-1)at 40℃,which is almost 3 times of the baseline.Also,the optimized polymer electrolyte demonstrates outstanding stable cycling in the LiFePO_(4)/Li and LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)/Li(3.0-4.4 V,200 cycles)based all-solid-state lithium batteries at 40℃. 展开更多
关键词 all-solid-state battery high voltage li-ion conductivity molecular interaction poly(ethylene oxide)
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Flexible and Robust Functionalized Boron Nitride/Poly(p‑Phenylene Benzobisoxazole)Nanocomposite Paper with High Thermal Conductivity and Outstanding Electrical Insulation 被引量:1
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作者 Lin Tang Kunpeng Ruan +3 位作者 Xi Liu Yusheng Tang Yali Zhang Junwei Gu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期423-437,共15页
With the rapid development of 5G information technology,thermal conductivity/dissipation problems of highly integrated electronic devices and electrical equipment are becoming prominent.In this work,“high-temperature... With the rapid development of 5G information technology,thermal conductivity/dissipation problems of highly integrated electronic devices and electrical equipment are becoming prominent.In this work,“high-temperature solid-phase&diazonium salt decomposition”method is carried out to prepare benzidine-functionalized boron nitride(m-BN).Subsequently,m-BN/poly(pphenylene benzobisoxazole)nanofiber(PNF)nanocomposite paper with nacremimetic layered structures is prepared via sol–gel film transformation approach.The obtained m-BN/PNF nanocomposite paper with 50 wt%m-BN presents excellent thermal conductivity,incredible electrical insulation,outstanding mechanical properties and thermal stability,due to the construction of extensive hydrogen bonds andπ–πinteractions between m-BN and PNF,and stable nacre-mimetic layered structures.Itsλ∥andλ_(⊥)are 9.68 and 0.84 W m^(-1)K^(-1),and the volume resistivity and breakdown strength are as high as 2.3×10^(15)Ωcm and 324.2 kV mm^(-1),respectively.Besides,it also presents extremely high tensile strength of 193.6 MPa and thermal decomposition temperature of 640°C,showing a broad application prospect in high-end thermal management fields such as electronic devices and electrical equipment. 展开更多
关键词 poly(p-phenylene-2 6-benzobisoxazole)nanofiber Boron nitride Thermal conductivity Electrical insulation
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Innovative approach to boosting the chemical stability of AZ31 magnesium alloy using polymer-modified hybrid metal oxides
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作者 Mosab Kaseem Ananda Repycha Safira +3 位作者 Mohammad Aadil Tehseen Zehra Muhammad Ali Khan Arash Fattah-alhosseini 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1068-1081,共14页
Meeting the demands of complex and advanced applications requires the development of high-performance hybrid materials with unique properties.However,the integration of polymeric frameworks with MgO/WO_(3) composite l... Meeting the demands of complex and advanced applications requires the development of high-performance hybrid materials with unique properties.However,the integration of polymeric frameworks with MgO/WO_(3) composite layers faces challenges due to the lack of understanding of the formation mechanism and the challenge of determining the impact of self-assembled architecture on anticorrosive properties.In this study,we aimed to enhance the corrosion resistance of the MgO layer produced by plasma electrolysis(PE)of AZ31 Mg alloy by incorporating WO_(3) with partially phosphorated poly(vinyl alcohol)(PPVA).Two types of porous MgO layers were produced using the PE process with an alkaline-phosphate electrolyte,one with and one without WO_(3) nanoparticles,which were subsequently immersed in an aqueous solution of PPVA.Incorporating PPVA into the WO_(3)-MgO layer resulted in hybrids being deposited in a fragmented manner,creating a“laminar reef-like structure”that sealed most of the structural defects in the layer.The PPVA-sealed WO_(3)-based coating exhibited superior corrosion resistance compared to the other samples.Computational analyses were employed to explore the mechanism underlying the formation of PPVA/WO_(3) hybrids on the MgO layer.These findings suggest that PPVA-WO_(3)-MgO hybrid coatings can potentially improve corrosion resistance in various fields. 展开更多
关键词 Plasma electrolysis poly(vinyl alcohol) Tungsten trioxide SEALING CORROSION DFT.
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Tuning the cross-linked structure of basic poly(ionic liquid)to develop an efficient catalyst for the conversion of vinyl carbonate to dimethyl carbonate
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作者 Zhaoyang Qi Shiquan Zhong +4 位作者 Huiyun Su Changshen Ye Limei Ren Ting Qiu Jie Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期106-116,共11页
Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other fields.The current primary industrial process employs a conventional sodium ... Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other fields.The current primary industrial process employs a conventional sodium methoxide basic catalyst to produce DMC through the transesterification reaction between vinyl carbonate and methanol.However,the utilization of this catalyst presents several challenges during the process,including equipment corrosion,the generation of solid waste,susceptibility to deactivation,and complexities in separation and recovery.To address these limitations,a series of alkaline poly(ionic liquid)s,i.e.[DVBPIL][PHO],[DVCPIL][PHO],and[TBVPIL][PHO],with different crosslinking degrees and structures,were synthesized through the construction of cross-linked polymeric monomers and functionalization.These poly(ionic liquid)s exhibit cross-linked structures and controllable cationic and anionic characteristics.Research was conducted to investigate the effect of the cross-linking degree and structure on the catalytic performance of transesterification in synthesizing DMC.It was discovered that the appropriate cross-linking degree and structure of the[DVCPIL][PHO]catalyst resulted in a DMC yield of up to 80.6%.Furthermore,this catalyst material exhibited good stability,maintaining its catalytic activity after repeated use five times without significant changes.The results of this study demonstrate the potential for using alkaline poly(ionic liquid)s as a highly efficient and sustainable alternative to traditional catalysts for the transesterification synthesis of DMC. 展开更多
关键词 poly(ionic liquid) Cross-linking degree Dimethyl carbonate production Transesterification reaction Mechanism
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Dual-salt poly(tetrahydrofuran) electrolyte enables quasi-solid-state lithium metal batteries to operate at -30 ℃
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作者 Zhiyong Li Zhuo Li +1 位作者 Rui Yu Xin Guo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期456-463,共8页
The stable operation of solid-state lithium metal batteries at low temperatures is plagued by severe restrictions from inferior electrolyte-electrode interface compatibility and increased energy barrier for Li^(+)migr... The stable operation of solid-state lithium metal batteries at low temperatures is plagued by severe restrictions from inferior electrolyte-electrode interface compatibility and increased energy barrier for Li^(+)migration.Herein,we prepare a dual-salt poly(tetrahydrofuran)-based electrolyte consisting of lithium hexafluorophosphate and lithium difluoro(oxalato)borate(LiDFOB).The Li-salt anions(DFOB−)not only accelerate the ring-opening polymerization of tetrahydrofuran,but also promote the formation of highly ion-conductive and sustainable interphases on Li metal anodes without sacrificing the Li^(+)conductivity of electrolytes,which is favorable for Li^(+)transport kinetics at low temperatures.Applications of this polymer electrolyte in Li||LiFePO_(4)cells show 82.3%capacity retention over 1000 cycles at 30℃and endow stable discharge capacity at−30℃.Remarkably,the Li||LiFePO4 cells retain 52%of their room-temperature capacity at−20℃and 0.1 C.This rational design of dual-salt polymer-based electrolytes may provide a new perspective for the stable operation of quasi-solid-state batteries at low temperatures. 展开更多
关键词 poly(tetrahydrofuran) Dual-salt electrolyte Solidel ectrolyte interphase Low-temperature operation Quasi-solid-state battery
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Synergy of Polydopamine‑Assisted Additive Modification and Hierarchical‑Morphology Poly(Vinylidene Fluoride)Nanofiber Mat for Ferroelectric‑Assisted Triboelectric Nanogenerator
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作者 Junseo Gu Donghyun Lee +2 位作者 Jeonghoon Oh Hyeokjun Si Kwanlae Kim 《Advanced Fiber Materials》 SCIE EI CAS 2024年第6期1910-1926,共17页
In the last decade,numerous physical modification methods have been introduced to enhance triboelectric nanogenerator(TENG)performance although they generally require complex and multiple fabrication processes.This st... In the last decade,numerous physical modification methods have been introduced to enhance triboelectric nanogenerator(TENG)performance although they generally require complex and multiple fabrication processes.This study proposes a facile fabrication process for Poly(vinylidene fluoride)(PVDF)nanofiber(NF)mats incorporating additive and nonadditive physical modifications.Patterned PVDF NF mats are prepared by electrospinning using a metal mesh as the NF collector.As a negative triboelectric material,the TENG with the patterned PVDF NF mat exhibits superior performance owing to the engineered morphology of the contact layer.PVDF is crucial in TENGs owing to its superior ferroelectric properties and surface charge density when combined with specific electroceramics.Hence,the synergy of the physical modification methods is achieved by incorporating BaTiO3(BTO)nanoparticles(NPs)into the PVDF.By functionalizing BTO NPs with polydopamine,the TENG performance is further improved owing to the enhanced dispersion of NPs and improved crystallinity of the PVDF chains.Utilizing large NPs produces a nanopatterning effect on the NF surface,thereby resulting in the hierarchical structure of the NF mats.The source of the voltage signals from the TENG is analyzed using fast Fourier transform. 展开更多
关键词 Triboelectric nanogenerator Electrospinning Physical modification poly(vinylidene fluoride) Barium titanate polyDOPAMINE
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Efficient and selective upcycling of waste polylactic acid into acetate using nickel selenide
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作者 Bing Lan Yinfang Chen +4 位作者 Nantian Xiao Na Liu Chao Juan Chuan Xia Fan Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期575-584,I0012,共11页
The conversion of waste polylactic acid(PLA)plastics into high-value-added chemicals through electrochemical methods is a promising and sustainable approach.However,developing efficient and highly selective catalysts ... The conversion of waste polylactic acid(PLA)plastics into high-value-added chemicals through electrochemical methods is a promising and sustainable approach.However,developing efficient and highly selective catalysts for lactic acid oxidation reaction(LAOR)and understanding the reaction process are challenging.Here,we report the electrooxidation of waste PLA to acetate at a high current density of 100 mA cm-2 with high Faraday efficiency(~95%)and excellent stability(>100 h)over a nickel selenide nanosheet catalyst.In addition,a total Faraday efficiency of up to 190%was achieved for carboxylic acids,including acetic acid and formic acid,by coupling with the cathodic CO_(2) reduction reaction.In situ experimental results and theoretical simulations revealed that the catalytic activity center of LAOR was dynamically formed NiOOH species,and the surface-adsorbed SeO_(x) species accelerated the formation of Ni~(3+)species,thus promoting catalytic activity.The mechanism of lactic acid electrooxidation was further elucidated.Lactic acid was dehydrogenated to produce pyruvate first and then formed CH_3CO due to preferential C-C bond cleavage,resulting in the presence of acetate.This work demonstrated a sustainable method for recycling waste PLA and CO_(2) into high-value-added products. 展开更多
关键词 Waste plastic upcycling poly(lactic acid) Lactic acid electro-oxidation Acetic acid
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TOPCon太阳电池背面叠层poly工艺的优化及其对电性能的影响
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作者 凡金星 刘绍洋 高纪凡 《太阳能》 2024年第4期73-79,共7页
通过增加TOPCon太阳电池poly层中的磷掺杂浓度可以增强poly层与硅基底之间的钝化效果并提高poly层与金属电极间的接触能力,但过高的掺杂浓度会导致磷原子扩散到硅基底,破坏氧化层与硅基底之间的界面钝化效果。为了解决这一问题,提出在p... 通过增加TOPCon太阳电池poly层中的磷掺杂浓度可以增强poly层与硅基底之间的钝化效果并提高poly层与金属电极间的接触能力,但过高的掺杂浓度会导致磷原子扩散到硅基底,破坏氧化层与硅基底之间的界面钝化效果。为了解决这一问题,提出在poly层中间增加一层薄的氧化层作为阻挡层(即叠层poly工艺,下文简称为“叠层工艺”)的方案,将原本单一的poly-Si磷掺杂进行双层分布,底层poly-Si轻掺杂,表层poly-Si重掺杂;对常规工艺和叠层工艺制备TOPCon的太阳电池进行对比试验后,进一步优化叠层工艺,调整中间氧化层厚度,并研究不同中间氧化层厚度的叠层工艺对TOPCon太阳电池电性能的影响。实验结果表明:1)叠层工艺可以提高TOPCon太阳电池的电性能;2)当中间氧化层厚度提升至1.5 nm时,太阳电池的光电转换效率达到最高值(25.66%)。但中间氧化层的厚度是一个需要精确控制的工艺参数,需找到最佳的厚度平衡点,以提高太阳电池性能。 展开更多
关键词 TOPCon太阳电池 poly 磷掺杂浓度 钝化效果
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Study on the repairing effect of poly(N-vinylpyrrolidone-co-methacrylic acid)on permed or bleached damaged hair
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作者 Yun Zhang Huan Wang +2 位作者 Yuyun Yang Sihan Yu Yuhua Cao 《日用化学工业(中英文)》 CAS 北大核心 2024年第12期1481-1488,共8页
The repairing effect of poly(N-vinylpyrrolidone-co-methacrylic acid)on permed or bleached damaged hair was studied.The combing and tensile strength of permed and bleached hair before and after treatment with the copol... The repairing effect of poly(N-vinylpyrrolidone-co-methacrylic acid)on permed or bleached damaged hair was studied.The combing and tensile strength of permed and bleached hair before and after treatment with the copolymer solution were tested,and the effects of the mass fraction of copolymer solution and immerseing time on the combing and tensile strength for permed or bleached damaged hair were investigated.The repair mechanism of permed or bleached damaged hair was also explored.The results show that when the immersing time is 3 hours,the tensile strength of the permed hair increases with the mass fraction of the copolymer solution Tensile strength within 0%-0.3%,but no obvious change is observed when250 Yield strength the mass fraction is over 0.3%.Therefore,the optimal mass 200 fraction of the copolymer solution for repairing the permed hair(cN/dtex)is 0.3%.Similarly,the optimal mass fraction of the copolymer 150strength/solution for repairing the bleached hair is 0.5%.Furthermore,the effects of immersing time on the tensile strength of the100Tensile damaged hair fibers were compared between the permed and90 bleached hair before and after treatment with the copolymer500.40.30.500.10.2 solution.Coincidentally,the optimal immersion time for permedw(P(NVP-co-MAA))/%or bleached damaged hair is both 2 hours.The tensile strength of the permed and bleached hair soaked in 0.3%and 0.5%copolymer solutions for 2 hours increases by 15.55%and 18.12%,respectively,compared to untreated hair.Through infrared spectroscopy analysis,it is found that the amide II band in hair fibers shifted to the blue after repair,with the wave number shift of 11.12 and 11.09 cm^(-1),which confirm the formation of hydrogen bonds in the hair samples.Additionally,the urea hydrogen bond disruption experiment demonstrates that urea does not disrupt the hydrogen bonds in untreated hair fibers,but prevents the formation of new hydrogen bonds in damaged hair fibers.It further validates that the improvement of the tensile strength of the copolymer treated damaged hair fibers is mainly due to the formation of hydrogen bonds.After treatment with the copolymer,the dry and wet combing friction decrease by 30.73%and 28.55%for the permed hair,and decrease by 28.55%and 24.83%for the bleached hairs,respectively.The scanning electron microscope shows that the copolymer can flatten the cuticle and fill the space between the raised cuticles. 展开更多
关键词 poly(N-vinylpyrrolidone-co-methacrylic acid) permed hair bleached hair tensile strength COMBING
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Poly-( hydroxypropyl,ethanediami-DL-Aspartamide hydrogels As enzyme delivery carrier
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《Chinese Journal of Biomedical Engineering(English Edition)》 2001年第4期169-170,共2页
关键词 As DL poly hydroxypropyl ethanediami-Dl-aspartamide hydrogels As enzyme delivery carrier
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Anion competition for Li^(+)solvated coordination environments in poly(1,3 dioxolane)electrolyte to enable high-voltage lithium metal solid-state batteries
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作者 Qiujun Wang Yanqiang Ma +6 位作者 Xiaomeng Jia Di Zhang Zhaojin Li Huilan Sun Qujiang Sun Bo Wang Li-Zhen Fan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期633-641,共9页
Gel-based polymer electrolytes are limited by the polarity of the residual solvent,which restricts the coupling-breaking behaviour during Li^(+)conduction,resulting in the Li^(+)transport kinetics being greatly affect... Gel-based polymer electrolytes are limited by the polarity of the residual solvent,which restricts the coupling-breaking behaviour during Li^(+)conduction,resulting in the Li^(+)transport kinetics being greatly affected.Here,we designed anion competitive gel polymer electrolyte(ACPE)by introducing lithium difluoro(oxalato)borate(LiDFOB)anion into the 1,3-dioxolane(DOL)in situ polymerisation system.ACPE enhances the ionic dipole interaction between Li^(+)and the solvent molecules and synergizes with Li^(+)across the solvation site of the polymer ethylene oxide(EO)unit,combination that greatly improves the Li^(+)transport efficiency.As a result,ACPE exhibits 1.12 mS cm^(−1)ionic conductivity and 0.75 Li^(+)transfer number at room temperature.Additionally,this intra-polymer solvation sheath allows preferential desolvation of DFOB−,which contributes to the formation of kinetically stable anion-derived interphase and effectively mitigates side reactions.Our results demonstrate that the assembled Li||NCM622 solid-state battery exhibits lifespan of over 300 cycles with average Coulombic efficiency of 98.8%and capacity retention of 80.3%.This study introduces a novel approach for ion migration and interface design,paving the way for high-safety and high-energy-density batteries. 展开更多
关键词 Li-metal batteries poly(1 3-dioxolane) In situ polymerization Solid-state polymer electrolytes Anion competition
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Stable Cycling of All-Solid-State Lithium Batteries Enabled by Cyano-Molecular Diamond Improved Polymer Electrolytes
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作者 Yang Dai Mengbing Zhuang +5 位作者 Yi-Xiao Deng Yuan Liao Jian Gu Tinglu Song Hao Yan Jin-Cheng Zheng 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第10期561-575,共15页
The interfacial instability of the poly(ethylene oxide)(PEO)-based electrolytes impedes the long-term cycling and further application of all-solid-state lithium metal batter-ies.In this work,we have shown an effective... The interfacial instability of the poly(ethylene oxide)(PEO)-based electrolytes impedes the long-term cycling and further application of all-solid-state lithium metal batter-ies.In this work,we have shown an effective additive 1-adaman-tanecarbonitrile,which con-tributes to the excellent per-formance of the poly(ethylene oxide)-based electrolytes.Owing to the strong interaction of the 1-Adamantanecarboni-trile to the polymer matrix and anions,the coordination of the Li^(+)-EO is weakened,and the binding effect of anions is strengthened,thereby improving the Li^(+)conductivity and the electrochemical stability.The diamond building block on the surface of the lithium anode can sup-press the growth of lithium dendrites.Importantly,the 1-Adamantanecarbonitrile also regulates the formation of LiF in the solid electrolyte interface and cathode electrolyte interface,which contributes to the interfacial stability(especially at high voltages)and protects the electrodes,enabling all-solid-state batteries to cycle at high voltages for long periods of time.Therefore,the Li/Li symmetric cell undergoes long-term lithium plating/stripping for more than 2000 h.1-Adamantanecarbonitrile-poly(ethylene oxide)-based LFP/Li and 4.3 V Ni_(0.8)Mn_(0.1)Co_(0.1)O_(2)/Li all-solid-state batteries achieved stable cycles for 1000 times,with capacity retention rates reaching 85%and 80%,respectively. 展开更多
关键词 1-Adamantanecarbonitrile(ADCN) poly(ethylene oxide) All-solid-state batteries Interfacial stability High voltage
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