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Covalent triazine frameworks modified by ultrafine Pt nanoparticles for efficient photocatalytic hydrogen production
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作者 Xu Han Xueying Ge +7 位作者 wen-wen he Wangwang Shen Tao Zhou Jian-Sen Wang Rong-Lin Zhong Abdullah MAl-Enizi Ayman Nafady Shengqian Ma 《Nano Research》 SCIE EI CSCD 2024年第6期4908-4915,共8页
Pt nanoparticles(PtNPs)as active species have always been considered as one of the best semiconductor materials for photocatalytic hydrogen production.In this study,a Schottky heterojunction has been successfully cons... Pt nanoparticles(PtNPs)as active species have always been considered as one of the best semiconductor materials for photocatalytic hydrogen production.In this study,a Schottky heterojunction has been successfully constructed by evenly loading ultrafine PtNPs onto a triazine-based covalent organic frameworks(COFs).This strategy maintained the high activity of these ultra-small PtNPs while maximizing the utilization of the Pt active sites.The fabricated PtNPs@covalent triazine-based framework-1(CTF-1)composite accomplished a significantly high rate of hydrogen evolution(20.0 mmol·g^(−1)·h^(−1),apparent quantum efficiency(AQE)=7.6%,atλ=450 nm)with 0.40 wt.%Pt loading,giving rise to a 44-fold-increase in the efficiency of the photocatalytic hydrogen production compared to the pristine CTF-1.Theoretical calculations revealed that the strong electron transfer(Q(Pt)=−0.726 qe,in the analysis of Bader charge,Q(Pt)is the charge quantity transferred from Pt cluster to CTF-1,and qe is the unit of charge transfer quantity)between PtNPs and CTF-1 triggers a strong interaction,which makes PtNPs being firmly attached to the structure of CTF-1,thereby enabling high stability and excellent hydrogen production efficiency.Importantly,the hydrogen binding free energy(ΔGH*)of PtNPs@CTF-1 is much lower than that of the unmodified CTF-1,leading to a much lower intermediate state and hence a significant improvement in photocatalytic performance.The overall findings of this work provide a new platform to incorporate metallic NPs into COFs for the design and fabrication of highly efficient photocatalysts. 展开更多
关键词 Pt nanoparticles covalent triazine-based framework-1(CTF-1) PHOTOCATALYSTS hydrogen evolution reaction
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Sulfonated poly(aryl ether ketone sulfone)modified by polyoxometalates LaW_(10) clusters for proton exchange membranes with high proton conduction performance
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作者 Meng-Long Liu Xu Han +6 位作者 wen-wen he Feng-Yu Jiang Fang Ji Wang-Wang Shen Tao Zhou Jing-Mei Xu Ya-Qian Lan 《Tungsten》 EI CSCD 2024年第2期454-464,共11页
Polyoxometalates(POMs)are classified as solid superacids which can exhibit notable proton conductivity,making them a promising functional inorganic filler for enhancing the proton conductivity of proton exchange membr... Polyoxometalates(POMs)are classified as solid superacids which can exhibit notable proton conductivity,making them a promising functional inorganic filler for enhancing the proton conductivity of proton exchange membranes(PEMs).In this study,a series of hybrid membranes were obtained by molecular-level hybridization of Weakley-type POM Na_(7)H_(2)LaW_(10)O_(36)(LaW_(10))clusters into sulfonated poly(aryl ether ketone sulfone)(SPAEKS).All hybrid membranes exhibited greater proton conductivity than the pristine membrane in the 30–80℃temperature range.When the doping amount of LaW 10 reached 7 wt.%,the proton conductivity of M-LaW 10^(-7)achieved 64 mS·cm^(−1)at 80℃.Lanthanide ions'high coordination number property and variable coordination environment can aid to attract more water molecules from the environment.LaW 10 and these bound water can construct denser hydrogen bonds with–SO_(3)H of SPAEKS.These intensive hydrogen bonds will facilitate the constitution of more continuous proton transport channels,and improve the proton conductivity of the hybrid membrane.This work off ers a fresh approach to using POMs containing rare-earth components in PEMs. 展开更多
关键词 POLYOXOMETALATES Rare-earth elements Sulfonated poly(arylene ether ketone sulfone) Proton exchange membranes
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有机胍催化法可控合成聚乳酸系环境友好材料 被引量:6
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作者 王子羽 何文文 +4 位作者 徐云龙 黄伟 江伟 李弘 张全兴 《高分子学报》 SCIE CAS CSCD 北大核心 2018年第7期786-796,共11页
可控聚合反应是进行大分子结构设计及获得优异性能聚合物的重要手段.作者近年来设计合成/筛选了若干种无毒有机胍化合物作为催化剂/引发剂,实现了可控缩聚、开环聚合、解聚反应.以生物质有机胍肌酐(CR)为催化剂实现了L-/D-乳酸(LLa/DLa... 可控聚合反应是进行大分子结构设计及获得优异性能聚合物的重要手段.作者近年来设计合成/筛选了若干种无毒有机胍化合物作为催化剂/引发剂,实现了可控缩聚、开环聚合、解聚反应.以生物质有机胍肌酐(CR)为催化剂实现了L-/D-乳酸(LLa/DLa)的等规熔融缩聚(Iso-MP),高产率(85%)合成得到了高等规度聚L-/D-乳酸(PLLA、PDLA,Iso.>98%);以CR催化Iso-MP反应得的中分子量聚L-/D-乳酸(Mw=2.2×104,Iso.=98.2%)为原料经熔融-固相缩聚(MP-SSP)联用法合成得到高分子量、高等规度PLLA、PDLA(Mw=1.0×105,Iso.>98%),聚合物热分解温度(Td,i=324.3°C)较Sn Cl2·2H2O催化法合成聚合物高120°C;由CR催化LLa/DLa的Iso-MP及其后解聚反应合成得到了光学纯L-/D-丙交酯(LLA、DLA,e.e.100%),副产的聚合物残渣r-PLLA/r-PDLA经水解后循环用作LLA/DLA合成原料,光学纯LLA/DLA总产率达到98%.设计合成了数种位阻型有机胍羧酸盐(HBG·OAc、CRA、CRG、CRL、TBDA),表征了其分子结构,用以实现LLA的活性开环聚合.合成了单一光学构型的L-乳酸-L-丝氨酸吗啉二酮(3S,6S-BMMD),测定了其单晶分子结构并以CRA为引发剂进行了3S,6S-BMMD的活性开环聚合,聚合物经脱保护后合成得到双亲功能基化生物降解聚合物聚(L-乳酸-L-丝氨酸).采用1H-NMR、13C-NMR跟踪监测法表征了大分子物种的精细结构,推断了上述可控反应的机理. 展开更多
关键词 有机胍 立构专一性缩聚 活性开环聚合 环境友好聚合物
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IL-6 and INF-γ levels in patients with brucellosis in severe epidemic region,Xinjiang,China 被引量:9
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作者 Zhi-Qiang Lin Guo-Yue Lin +10 位作者 wen-wen he Chi Zhang Rui Zhang Yuan-Da Li Fan Wang Ying Qin Li Duan Dou-Dou Zhao Xiao-Juan Qu Hui Gao Hai Jiang 《Infectious Diseases of Poverty》 SCIE 2020年第3期84-89,共6页
Background:The incidence of brucellosis,which is caused by the Brucella species of bacteria,is rapidly rising worldwide;however,few studies have investigated the immune response to this pathogen and clinical biochemic... Background:The incidence of brucellosis,which is caused by the Brucella species of bacteria,is rapidly rising worldwide;however,few studies have investigated the immune response to this pathogen and clinical biochemical features.In this paper,we examined the levels of various cytokines and inflammatory factors as well as clinical course characteristics in patients with brucellosis,in order to provide evidence for the diagnosis,assessment,and prognosis of this infectious disease.Methods:A total of 191 brucellosis inpatients(50 acute cases and 141 chronic cases),as well as 60 healthy control subjects,were included in the analysis.We investigated changes in the levels of six cytokines(IL-4,IL-6,IL-10,IL-17,TNF-α,INF-γ)and related clinical biochemical markers in patients with acute and chronic brucellosis in Xinjiang,China.Possible factors were statistically analyzed using the t test,χ2 test,z test and a multivariate logistic stepwise regression test.Results:We found that IL-4,IL-6,IL-10,IL-17,IFN-γ,and TNF-αlevels were higher in those with brucellosis than in controls(P<0.05).With regard to disease progression,procalcitonin(PCT)and C-reactive protein(CRP)levels were significantly higher in those with an acute infection compared to chronic cases(P<0.05).We found that the expression of all six cytokines tested was closely related to the degree of brucellosis using univariate logistic regression;however,only IL-6 and INF-γlevels were independent factors associated with the severity of brucellosis.Conclusions:Assessing cytokine levels in patients with acute and chronic brucellosis is not only useful for detecting the immune response,but can also be indicative of the severity of brucellosis.In particular,we propose IL-6 and INF-γlevels may be useful independent predictive factors in the clinical evaluation and diagnosis of brucellosis. 展开更多
关键词 BRUCELLOSIS CYTOKINES Immunity IL-6 INF-Γ
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Precise modification of poly(aryl ether ketone sulfone)proton exchangemembranes with positively charged bismuth oxide clusters for high proton conduction performance 被引量:1
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作者 Yi-Zhuo Yin Zhen-Guo Zhang +6 位作者 wen-wen he Jing-Mei Xu Feng-Yu Jiang Xu Han Wan-Ting Di ZheWang Shengqian Ma 《SusMat》 2022年第1期76-89,共14页
In the field of proton exchange membranes(PEMs),it is still a great challenge to explore new Nafion alternatives,maintaining the high proton conductivity and lowering the cost of practical application.In this work,a s... In the field of proton exchange membranes(PEMs),it is still a great challenge to explore new Nafion alternatives,maintaining the high proton conductivity and lowering the cost of practical application.In this work,a series of low sulfonated poly(aryl ether ketone sulfone)(SPAEKS)membranes hybridized by[Bi_(6)O_(5)(OH)_(3)]_(2)(NO_(3))10⋅6H_(2)O(H_(6)Bi_(12)O_(16))have been successfully fabricated.When the doping amount of H6Bi12O16 reaches 5 wt%,the DS15-Bi12-5 showing the best proton conductive ability and mechanical properties.The proton conductivity can achieve 72.8 mS⋅cm−1 at 80℃ and the tensile strength can reach 43.57 MPa.Confirmed by experimental data and activation energy(Ea)calculations,the existence of Bi cluster makes more hydrogen bonds,providing additional proton hopping sites and offers more proton transport vehicles,leading to a high proton conduction performance.This work proved that polyoxometalates(POMs)can replace the role of sulfonate groups in SPAEKS to a certain extent and work out the defects of high sulfonation,making a remarkable contribution to the practical application of low sulfonated SPAEKS. 展开更多
关键词 POLYOXOMETALATES proton conductivity proton exchange membrane sulfonated poly(aryl ether ketone sulfone)
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