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Effects of molecular conformation on buried interface passivation and efficient perovskite solar cell realization employing fluorine substituted benzoic acid 认领 引用
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作者 Boyan Li Rongbo Wang +8 位作者 Ya Wang Wentao Wu Weitao Yan Handong Zhang Xingyuan Zhong Juntao Zhao Liyi Yao Wei-Hua Wang Yi Ding 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2026年第1期826-831,I0018,共6页
Benzoic acid containing fluorine atom at ortho-,meta-,and para-position are employed as self-assembled monolayers to modify the buried interface in perovskite solar cells(PSCs).It is demonstrated that the position of ... Benzoic acid containing fluorine atom at ortho-,meta-,and para-position are employed as self-assembled monolayers to modify the buried interface in perovskite solar cells(PSCs).It is demonstrated that the position of fluorine atom influences the passivation effect and para-fluorinated one provided the most substantial performance enhancement mainly originating from ameliorated contact and energy band alignment between NiOx and perovskite,improved perovskite quality and defect healing.Resultantly,PSC with a power conversion efficiency of 24%can be achieved.Meanwhile,which can maintain 96.8%of the initial PCE after a 1000 h storage,presenting enhanced durability.This work highlights the critical role of molecular functionality and conformation in the buried interface modification of PSCs,providing valuable insights for future developments. 展开更多
关键词 Perovskite solar cells F atom substituted benzoic acids Buried interface modification
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Copper-Catalyzed Site-and Enantioselective C-H Cyanation of Trisubstituted Allenes 认领 引用
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作者 Jiajun Zhang Pinhong Chen Guosheng Liu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2026年第11期1729-1734,共6页
Chiral allenes are privileged structural motifs found in numerous natural products and bioactive molecules,consequently,the synthesis of these scaffolds—especially polysubstituted chiral allenes—has garnered signifi... Chiral allenes are privileged structural motifs found in numerous natural products and bioactive molecules,consequently,the synthesis of these scaffolds—especially polysubstituted chiral allenes—has garnered significant research interest.Among these methods,direct asymmetric functionalization of allenic sp²C−H bond has been recognized as a powerful strategy for the modification of allenes,enabling late‑stage functionalization(LSF)of allene‑containing bioactive compounds.In recent years,Cu(II)‑bound nitrogen‑centered radicals(NCRs)have been demonstrated to override innate radical preferences to achieve site‑selective C−H functionalizations,achieving the site‑selective C−H cyanation,arylation and alkynylation of allenes via a copper‑catalyzed radical relay process,where the HAA process exclusively occurs at sp2C−H bonds.Although the enantioselective version has been achieved for the reaction of 1,3‑disubstituted allenes,which afforded the chiral trisubstituted allenic nitriles with excellent enantioselectivities,the reactions of trisubstituted allenes exhibited significantly poor enantioselectivity.Herein,we report a copper‑catalyzed site‑and enantioselective sp2C−H cyanation of trisubstituted allenes.This reaction was catalyzed by CuOAc and Box ligand L1 in a mixture solvent of tert‑amyl alcohol((ᵗ)^AmOH),acetone and(trifluoromethyl)benzene at−40℃.This method efficiently afforded a broad array of tetrasubstituted axially chiral allenic nitriles in good to excellent yields with excellent enantioselectivities. 展开更多
关键词 Asymmetric copper catalysis Radical cyanation sp2C−H functionalization Hydrogen atom abstract Nitrogen‑centered radicals Chiral tetra‑substituted allenic nitriles Site‑selectivity Box ligand
Si Alloying Enables High Performance in Ce-Substituted Hot-Deformed Nd-Fe-B Magnets 认领 引用
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作者 Feifei Li Yi Ge +4 位作者 Yucheng Hu Xiaowei Zhang Renquan Wang Jun Li Ying Liu 《Rare Metals》 SCIE EI CAS CSCD 2026年第5期310-321,共12页
High levels of Ce substitution typically degrade the magnetic performance of hot-deformed Nd-Fe-B magnets,posing challenges for developing resource-efficient permanent magnets.Here,we demonstrate that minor Si alloyin... High levels of Ce substitution typically degrade the magnetic performance of hot-deformed Nd-Fe-B magnets,posing challenges for developing resource-efficient permanent magnets.Here,we demonstrate that minor Si alloying in(Nd0.6Ce0.4)-Fe-B hot-deformed magnets effectively compensates for this degradation and enables enhanced magnetic performance.It yields a coercivity of 9.5 kOe,a remanence of 13.2 kG,and a maximum energy product of 40.1 MGOe,thereby demonstrating superior magnetic performance compared with previously reported Ce-or La/Ce-substituted magnets at comparable substitution levels.Microstructural analyses reveal that Si effectively refines the grains and generates Si-rich/Fe-poor grain-boundary films that weaken intergranular exchange coupling and thereby enhance magnetic performance.These results demonstrate that Si-driven grain-boundary chemistry engineering offers an effective route to mitigate the magnetic performance degradation of Ce-rich Nd-Fe-B magnets. 展开更多
关键词 Ce substitution hot-deformed magnet magnetic performance REFe2phase Si doping
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Review of the structural properties and interfacial reactions of Al-substituted goethite,hematite and ferrihydrite 认领 引用
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作者 Yu LIANG Hongfeng CHEN +2 位作者 Jinling XU Mingxia WANG Wenfeng TAN 《Pedosphere》 SCIE CAS CSCD 2025年第1期42-52,共11页
Isomorphic substitution of ferric ion(Fe~(3+))by aluminum ion(Al~(3+))in iron(hydro)oxides is ubiquitous in natural environments.Aluminum substitution inevitably leads to changes in the microstructures,physicochemical... Isomorphic substitution of ferric ion(Fe~(3+))by aluminum ion(Al~(3+))in iron(hydro)oxides is ubiquitous in natural environments.Aluminum substitution inevitably leads to changes in the microstructures,physicochemical properties,and surface reactions of iron(hydro)oxides,which may have great impacts on the sequestration of nutrients and contaminants in soils and aquatic environments.Over the past decades,the structural properties and surface reactivity of Al-substituted iron(hydro)oxides have been intensively studied.Iron(hydro)oxides in various structural forms and with different Al substitution amounts present high application potentials in addressing environmental issues.A timely summary of the structural properties and interfacial reactions of the most common and representative Al-substituted iron(hydro)oxides is of significance.Herein,the effects of Al substitution on the structural properties and surface activities of iron(hydro)oxides were clarified according to the microstructure,crystal facets,surface site type and density,interfacial reaction mechanisms,and modeling parameters of iron(hydro)oxides.This review systematically elucidates how Al substitution affects the structural properties and surface reactions of iron(hydro)oxides,including the well crystallized goethite and hematite and the poorly crystallized ferrihydrite,providing theoretical guidance for further exploration of the mineralogical characteristics and environmental geochemical behaviors of iron(hydro)oxides. 展开更多
关键词 adsorption defective structure iron(hydro)oxide isomorphic substitution surface active site surface charge behavior
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Stabilizing the solid-solution sodium storage in Cr-substituted Na3V2(PO4)3 cathode for aqueous sodium-ion batteries with long-term stability 认领 引用 被引量：1
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作者 Qinyan Jian Tinghong Gao +4 位作者 Wensheng Yang Xinhai Wang Lishan He Jiarui Liu Yunjun Ruan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2025年第6期797-805,I0016,共9页
Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials ... Aqueous sodium-ion batteries(ASIBs) offer significant advantages for energy storage on a large scale,attributed to their economical cost,secure operatio n,and eco-friend ly natu re.Among the leading cathode materials for ASIBs,Na3V2(PO4)3(NVP) exhibits excellent structural stability and a high Na+diffusion coefficient,making it a promising option.However,the high solubility of vanadium-based materials in aqueous electrolytes engenders suboptimal cycling stability for Na3V2(PO4)3,constraining its application in ASIBs.Herein,the Cr-substituted Na3V1.3Cr0.7(PO4)3@C(NV1.3Cr0.7P) cathode material was synthesized via a simple sol-gel method.It is found that Cr substitution reduces the cell parameters of NV1.3Cr0.7P,effectively reinforcing the crystal structure.Furthermore,NV1.3Cr0.7P alters the Na+insertion/extraction mechanism,transforming the typical two-phase reaction between Na1V2(PO4)3and Na3V2(PO4)3into continuous solid-solution reactions with stable intermediates.The Cr substitution diminishes the sodium-ion diffusion energy barrier in NV1.3Cr0.7P,leading to smoother Na+insertion and extraction processes.Consequently,NV1.3Cr0.7P exhibits impressive cycling stability,retaining 74.8% of its capacity after 5,000 cycles at a current density of 5 A g-1,along with an outstanding rate performance of 79,2% at 10 A g-1.This work elucidates the stable Na+insertion/extraction processes in Cr-substituted NV1.3Cr0.7P,offering insights into the application of vanadium-based materials in aqueous sodium-ion batteries. 展开更多
关键词 Na3V2(PO4)3 Cr substitution Insertion/extraction mechanism Long-term cycling stability Aqueous sodium-ion battery
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Copper-substituted P3-type Na0.54Mn0.64Fe_(0.16)Mg0.1Cu0.1O2 cathode material for sodium-ion batteries with enhanced anionic redox reversibility 认领 引用
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作者 Zhe Mei Xun-Lu Li +10 位作者 Cui Ma Jie Zeng Chong-Yu Du Rui-Jie Luo Xuan Xu Zhe Qian Zi-Ting Zhou Ya Zhang Qian Cheng Yao-Guo Fang Yong-Ning Zhou 《Rare Metals》 SCIE EI CAS CSCD 2025年第5期2986-2996,共11页
P3-type manganese-iron-based cathodes with high specific capacity and abundant resource have attracted considerable attention for sodium-ion batteries.However,the long-term cycle stability of P3-type cathodes is still... P3-type manganese-iron-based cathodes with high specific capacity and abundant resource have attracted considerable attention for sodium-ion batteries.However,the long-term cycle stability of P3-type cathodes is still not satisfactory.In this work,we design a new quaternary manganese-iron-based cathode material(P3-Na0.54Mn0.64Fe_(0.16)Mg0.1Cu0.1O2)by Cu substitution.The strong covalent Cu-O bonds improve the structural stability and the reversibility of O redox during charge and discharge processes.Cu substitution also mitigates the structure change with less unit cell volume variation,and improves the Na-ion transport kinetics effectively.As a result,NMFMC delivers much improved cycling stability and rate capability compared with NMFM.It reveals that the charge compensation of NMFMC is mainly contributed by Mn3+/4+,Fe3+/3.5+and O2-/-during the charge and discharge processes,and Cu substitution can also enhance the activity and reversibility of Fe redox.This strategy provides a new pathway toward improving the stability and O redox reversibility of P3-type cathode materials for sodium-ion batteries. 展开更多
关键词 Sodium-ion batteries Cathode materials Cu substitution Anionic redox reversibility
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Molten salt synthesis of Al-substituted single-crystal NCMA cathodes: synergistic mitigation of structural degradation and enhanced electrochemical stability 认领 引用
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作者 Qi Guo Yu Zhang +2 位作者 Jinhua Xu Ting Li Cuiqin Li 《Rare Metals》 SCIE EI CAS CSCD 2025年第12期9887-9904,共18页
Nickel-rich single-crystal cathode materials are considered optimal candidates for next-generation lithiumion batteries(LIBs) due to their combination of high-energy density and crack-resistant,grain boundary-free str... Nickel-rich single-crystal cathode materials are considered optimal candidates for next-generation lithiumion batteries(LIBs) due to their combination of high-energy density and crack-resistant,grain boundary-free structures.However,cyclic stress induces repetitive surface slip in single crystals,promoting the propagation of microcracks and exposing fresh crystal planes to the electrolyte.This accelerates interfacial reactions and corrosion,increasing charge transfer resistance and active material loss,ultimately degrading electrochemical performance.To address the slip-related issues in single-crystal materials,we have synthesized a single-crystal quaternary cathode:LiNi0.8Co0.08Mn0.06Al0.06O2(SC-NCMA),via a molten salt method.The effects of Al incorporation on suppressing lamellar slip and enhancing electrochemical performance are systematically investigated by comparing the characteristics of SC-NCMA and ternary SC-NCM.The experimental results show that SC-NCMA retains 83.0% of its capacity after 200 cycles(2.7-4.3 V),significantly higher than the 66.5% capacity retention observed for SC-NCM.In situ X-ray diffraction(XRD) and X-ray photoelectron spectroscopy(XPS) analyses reveal that Al incorporation expands the(003) layer spacing,suppresses Li+/Ni2+ mixing,and mitigates lattice distortion induced by the H2-H3 phase transition by reinforcing the Al-O bonds.Furthermore,Al3+ not only optimizes Li+diffusion kinetics and reduces surface lattice oxygen loss but also facilitates the formation of a moderate-thickness cathodeelectrolyte interphase(CEI) layer,enabling the pouch cell to achieve 89.1% capacity retention after 400 cycles.Overall,this work validates molten salt synthesis as a viable route for producing single-crystal quaternary cathodes and elucidates Al's dual stabilization mechanism—through both crystal structure modulation and interfacial passivation—offering strategic insights into the development of advanced nickel-rich cathode systems. 展开更多
关键词 Molten salt synthesis Single-crystal cathode materials Al3+substitution Structural stability
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An Efficient Approach to 6,7-Disubstituted-1H-quinoxalin-2-ones 认领 引用
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作者 Xun LI Qing Ping HU +1 位作者 Xue Gui CUI Dong Hua WANG 《Chinese Chemical Letters》 SCIE CAS 2004年第12期1400-1402,共3页
A novel approach to the synthesis of 6,7-disubstituted-1H-quinoxalin-2-ones is described.The title compounds were regioselectively prepared by starting from substituted phenylamines andchloroacetyl chloride through th... A novel approach to the synthesis of 6,7-disubstituted-1H-quinoxalin-2-ones is described.The title compounds were regioselectively prepared by starting from substituted phenylamines andchloroacetyl chloride through the efficient sequence of acylation,nitration,reduction,intramolecular alkylation,and oxidation. 展开更多
关键词 6 7-Disubstituted-1H-quinoxalin-2-ones regioselective substituted phenylamine.
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Fe-catalyzed regioselective Friedel–Crafts hydroxyalkylation of N-substituted glyoxylamide with indoles 认领 引用 被引量：1
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作者 Yang Zheng Ren-Jun Li +3 位作者 Zhen Zhan Yan Zhou Li Hai Yong Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第1期41-46,共6页
An efficient regioselective Friedel-Crafts hydroxyalkylation of N-substituted glyoxylamide with various indoles catalyzed by Lewis acids was developed. The reactions proceeded smoothly at room temperature and the 2-hy... An efficient regioselective Friedel-Crafts hydroxyalkylation of N-substituted glyoxylamide with various indoles catalyzed by Lewis acids was developed. The reactions proceeded smoothly at room temperature and the 2-hydroxy-2-（1H-indol-3-yl）-N-substituted acetamide resulted from the reactions catalyzed by FeSO4 were synthesized in excellent yields （up to 93%）. While the bisindole compounds were obtained when FeCl3 was used as a catalyst in excellent yields （up to 92%）. A possible mechanism was proposed. 展开更多
关键词 Friedel-Crafts hydroxyalkylation N-substituted glyoxylamide Indole Lewis acid 2-Hydroxy-2-（1H-indol-3-yl）-N substituted acetamide Bisindole compounds
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Determination and QSAR Study on the Toxicity of Substituted Phenol against Qinghaiensis sp (Q67) 认领 引用 被引量：6
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作者 尤小军 刘辉 +1 位作者 杨郭英 王遵尧 《Chinese Journal of Structural Chemistry》 SCIE CAS 2009年第10期1311-1316,共6页
Toxicities （-1gEC50） of 16 phenolic compounds against Q67 were determined, and structural parameters as well as thermodynamic parameters of these compounds were obtained through fully optimized calculations by using... Toxicities （-1gEC50） of 16 phenolic compounds against Q67 were determined, and structural parameters as well as thermodynamic parameters of these compounds were obtained through fully optimized calculations by using B3LYP method of density functional theory （DFT） at the 6-311G^＊＊ level. Moreover, a 3-parameter （molecular average polarizability （α）, heat energy corrected value （Eth） and the most positive hydrogen atomic charge （qH^＋）） correlation model with R^2 = 0.981 and q^2 = 0.967 to predict -1gEC50 was obtained from experimental data based on the above-mentioned parameters as theoretical descriptors. Therein a was the most significant on -1gEC50. Variance Inflation Factors （VIF）, t-value and cross-validation were applied to verify the model, confirming that the resultant model has fairly better stability and predictive ability to predict -1gEC50 of similar compounds. 展开更多
关键词 qinghaiensis sp （Q67） toxicity （-1gEC50） quantitative structure-activity relationship （QSAR） density functional theory （DFT） environmental pollutant substituted phenol
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Synthesis,Characterization and Antibacterial Property of Strontium Half and Totally Substituted Hydroxyapatite Nanoparticles 认领 引用 被引量：4
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作者 LIN Yingguang YANG Zhuoru +1 位作者 CHENG Jiang WANG Lianshi 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第4期475-479,共5页
Nanoparticles of hydroxyapatite（HAP）, strontium half substituted hydroxyapatite （SrCaHAP） and strontium totally substituted hydroxyapatite （SrHAP） were prepared by sol-gel-supercritical fluid drying （SCFD） met... Nanoparticles of hydroxyapatite（HAP）, strontium half substituted hydroxyapatite （SrCaHAP） and strontium totally substituted hydroxyapatite （SrHAP） were prepared by sol-gel-supercritical fluid drying （SCFD） method. The nanoparticles were characterized by element content analysis, FT-IR, XRD and TEM, and the effects of strontium substitution on crystal structure, crystallinity, particle shape and antibacterial properties of the nanoparticles on Escherichia coli, Staphylococcus aureus, Lactobacillus were researched. Results show that strontium can half and totally substitute for calcium and enter the structure of apatite according to the initial atomic ratios of Sr/[Sr＋Ca] as 0.5, 1. The substitution decreases the IR wavenumbers of SrCaHAP and SrHAP, and changes the morphology of the nanoparticles from short rod shaped HAP to needle shaped SrCaHAP, and back to short rod shaped SrHAP. The crystallinity of HAP is higher than that of SrCaHAP, but is lower than that of SrHAP. Moreover, the antibacterial property of SrCaHAP and SrHAP are improved after the calcium is half and totally substituted by strontium. 展开更多
关键词 sol-gel-supercritical fluid drying nanoparticles strontium substituted hydroxyapatite antibacterial property
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Experimental and QSPR Studies on n-Octanol/water Partition Coefficient (lgKow) of Substituted Aniline 认领 引用 被引量：4
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作者 戴勇 江建林 +1 位作者 王遵尧 薛群 《Chinese Journal of Structural Chemistry》 SCIE CAS 北大核心 2007年第12期1449-1454,共6页
The n-octanol/water partition coefficients （lgKow） of 18 substituted anilines were determined at 25 ℃ by shake-flask method. The geometrical optimization of substituted anilines has been performed at B3LYP/6-311G^... The n-octanol/water partition coefficients （lgKow） of 18 substituted anilines were determined at 25 ℃ by shake-flask method. The geometrical optimization of substituted anilines has been performed at B3LYP/6-311G^＊＊ level with Gaussian98 program, and the molecular surface areas of substituted anilines were calculated using ChemOffice 2004 program. The calculated structural parameters of substituted anilines were used as theoretical descriptors and the two-parameter （molecular surface area （MA） and the energy of the highest occupied molecular orbital （EaoMo）） quantitative structure-property relationship （QSPR） model of lgKow for substituted aniline with molecular structural parameters was developed by multi-linear regression method. The regression coefficient square （r^2） is 0.990 and the standard deviation SE 0.109. The model was validated by variance inflation factors （VIF） and t-test, and the results show that there exists small self-correlation between variables of the model with perfect stability. The model gives results in good qualitative agreement with experimental data. At last, the model was applied to predict lgKow values of five substituted anilines whose lgKow values have not been determined experimentally. 展开更多
关键词 substituted aniline n-octanol/water partition coefficient shake-flask method DFT,quantitative structure-property relationship （QSPR）
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Fate of Parent and Substituted Polycyclic Aromatic Hydrocarbons in SBR/MBBR Treatment Process:Experimental Value Against Model Prediction 认领 引用 被引量：2
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作者 ZHAO Jing TIAN Weijun +3 位作者 LIU Shuhui QIAO Kaili DU Zhaoyang XIE Wenlong 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第2期479-489,共11页
The knowledge of the existence,distribution and fate of polycyclic aromatic hydrocarbons(PAHs)and substituted polycyclic aromatic hydrocarbons(SPAHs)in wastewater treatment plants(WWTPs)was vital for reducing their co... The knowledge of the existence,distribution and fate of polycyclic aromatic hydrocarbons(PAHs)and substituted polycyclic aromatic hydrocarbons(SPAHs)in wastewater treatment plants(WWTPs)was vital for reducing their concentrations entering the aquatic environment.The concentrations of 13 SPAHs and 16 PAHs were all determined in a WWTP with styrene butadiene rubber(SBR)in partnership with the moving bed biofilm reactor(MBBR)process.SPAHs presented a higher concentration lever than PAHs in nearly all samples.The total removal efficiencies of PAHs and SPAHs ranged from 64.0%to 71.36%and 78.4%to 79.7%,respectively.The total yearly loads of PAHs(43.0 kg)and SPAHs(73.0 kg)were mainly reduced by the primary and SBR/MBBR biological treatment stages.The tertiary treatment stage had a minor contribution to target compounds removal.According to a synthesis and improvement fate model,we found that the dominant processes changed as the chemical octanol water partition coefficient(Kow)increased.But the seasonal variations of experimental removal efficiencies were more obvious than that of predicted data.In the primary sedimentation tank,dissolution in the aqueous phase and sorption to sludge/particulate matter were controlling processes for the removal of PAHs and SPAHs.The sorption to sludge and biodegradation were the principal removal mechanisms during the SBR/MBBR biological treatment process.The contribution of volatilization to removal was always insignificant.Furthermore,the basic physicochemical properties and operating parameters influenced the fate of PAHs and SPAHs in the WWTP. 展开更多
关键词 substituted polycyclic aromatic hydrocarbons moving bed biofilm reactor removal efficiency fate process model
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Structural Characterization and Acute Toxicity Prediction of Substituted Aromatic Compounds by Using Molecular Vertexes Correlative Index 认领 引用 被引量：7
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作者 李建凤 廖立敏 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第4期557-563,共7页
A molecular structural characterization （MSC） method called molecular vertexes correlative index （MVCI） was used to describe the structures of 30 substituted aromatic compounds. Through multiple linear regression ... A molecular structural characterization （MSC） method called molecular vertexes correlative index （MVCI） was used to describe the structures of 30 substituted aromatic compounds. Through multiple linear regression （MLR） and stepwise multiple regression （SMR）, a quantitative structure-toxicity relationship （QSTR） model with 4 variables was obtained. The correlation coefficient （R） of the model was 0.9467. Through partial least-squares regression （PLS）, another QSTR model with 5 principal components was obtained. The correlation coefficient （R） of the model was 0.9518. Both models were evaluated by performing the cross-validation with the leave-one-out （LOO） procedure and the Cross-Validation （CV） correlation coefficients （Rcv） were 0.9208 and 0.9214, respectively. The results suggested good stability and predictability of the models, and the molecular vertexes correlative index could successfully describe the structures of the substituted aromatic compounds. 展开更多
关键词 substituted aromatics acute toxicity structural descriptors QSAR
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Synthesis of Substituted u-Oxo-bis[tetra-phenyl porphyrinatoiron] Compounds from Free Base Porphyrins by a One-pot Method 认领 引用 被引量：3
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作者 佘远斌 冯连顺 +1 位作者 王爱欣 李修艳 《Chinese Journal of Chemical Engineering》 SCIE EI CAS 2008年第3期369-372,共4页
A novel method for synthesis of substituted u-oxo-bis[tetraphenyl porphyrinatoiron] compotmds （[TRPPFe]20） based on the reaction among free base porphyrins （TRPPH2）, FeSO4·7H2O and H2O in one pot was proposed... A novel method for synthesis of substituted u-oxo-bis[tetraphenyl porphyrinatoiron] compotmds （[TRPPFe]20） based on the reaction among free base porphyrins （TRPPH2）, FeSO4·7H2O and H2O in one pot was proposed and investigated. Four kinds of [TRPPFe]2O were synthesized by this novel synthetic method, and their structures were characterized by elemental analysis, infrared spectra and UV-vis spectroscopy. The reaction conditions, including the effect of different iron salts on the formation of [TRPPFe]2O, the reaction time between FeSO4-7H2O and TRPPH2, the molar ratio of FeSO4-7H2O/TRPPH2 as well as the volume ratio of H2O/DMF, were investigated. The [TRPPFe]2O yield of 93% 98% could be obtained under the following optimal conditions： the reaction time of FeSOn-7H2O with TRPPH2 was about 10 h, the molar ratio of FeSOn-7H2O/TRPPH2 about 5 ： 1, and the volume ratio of H2O/DMF exceeded 2 ： 1. Further research indicated that only TRPPFeCI were formed once FeSOn-7H2O was replaced by FeCl2-4H2O, the reason of which might be that halogen ions in iron salts interfered the formation of [TRPPFe]2O, suggesting that halogen ions should be avoided in this novel synthetic method. 展开更多
关键词 substituted u-oxo-bis[tetraphenylporphyrinatoiron] compounds one-pot method free base porphyrins
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Oxygen permeation and phase structure properties of partially A-site substituted BaCo0.7Fe0.225Ta0.075O3-δ perovskites 认领 引用 被引量：2
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作者 Bo Jiang Hongwei Cheng +3 位作者 Longfei Luo Xionggang Lu Naijun Zhang Jizhong Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第2期164-170,共7页
Ba0.9R0.1Co0.TFe0.225Ta0.07503-δ （BRCFT, R = Ca, La or Sr） membranes were synthesized by a solid-state reaction. Metal cation Ca2＋, La3＋ or Sr2＋ doping on A-site partially substituted Ba2＋ in BaCoo.TFe0.225Ta0.... Ba0.9R0.1Co0.TFe0.225Ta0.07503-δ （BRCFT, R = Ca, La or Sr） membranes were synthesized by a solid-state reaction. Metal cation Ca2＋, La3＋ or Sr2＋ doping on A-site partially substituted Ba2＋ in BaCoo.TFe0.225Ta0.07503-δ oxides, and its subsequent effects on phase structure stability, oxygen permeability and oxygen desorption were systematically investigated by XRD, TG-DSC, Hz-TPR, O2-TPD techniques and oxygen permeation experiments. The partial substitution with Ca2＋, La3＋ or Sr2＋, whose ionic radii are smaller than that of Ba2＋, succeeded in stabilizing the cubic perovskite structure without formation of impurity phases, as revealed by XRD analysis. Oxygen-involving experi- ments showed that BRCFT with A-site fully occupied by Ba2＋ exhibited good oxygen permeation flux under He flow, reaching about 2.3 mL.min-l .cm-2 at 900 with I mm thickness. Of all the membranes, BLCFT membrane showed better chemical stability in CO2, owing to the reduction in alkalinity of the mixed conductor oxide by La doping. In addition, we also found the stability of the perovskite structure under reducing atmospheres was strengthened by increasing the size of A-site cation （Ba2＋〉La3＋〉SrZ＋〉Ca2＋）. 展开更多
关键词 perovskite phase stability oxygen permeation A-site substituted
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Synthesis of 3 or 4-Substituted Pyridine-2, 6-Dicarboxylic Acid 认领 引用 被引量：3
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作者 Xian Hong YIN Man Ya YANG +1 位作者 Hua Hong SHI Lian Quan GU 《Chinese Chemical Letters》 SCIE CAS 1999年第11期903-906,共4页
Various 4-alkoxypyridine-2, 6-dicarboxylic acids were synthesized starting from 2, 6- lutidine. Through aldol condensation and Michael addition, various 4-arylpyridine-2, 6-dicarboxylic acids were synthesized starting... Various 4-alkoxypyridine-2, 6-dicarboxylic acids were synthesized starting from 2, 6- lutidine. Through aldol condensation and Michael addition, various 4-arylpyridine-2, 6-dicarboxylic acids were synthesized starting from aromatic aldehydes and 2-acetylfuran. 展开更多
关键词 Michael reaction 2,6-lutidine analogues substituted pyridine-2,6-dicarboxylic acids
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Correlation Study of Toxicity of Substituted Phenols to River Bacteria and Their Biodegradability in River Water 认领 引用 被引量：3
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作者 XING YUAN GUANG-HUA LU LI-MIN SU 《Biomedical and Environmental Sciences》 SCIE CAS 2005年第5期281-285,共5页
To study the correlation of toxicity with biodegradability （BODT） in order to promote QSBR development and understand the degradation mechanism. Methods Toxicity of substituted phenols to river bacteria was determin... To study the correlation of toxicity with biodegradability （BODT） in order to promote QSBR development and understand the degradation mechanism. Methods Toxicity of substituted phenols to river bacteria was determined by the turbidities that were measured using a spectrophotometer （UV-190） at 530 nm against a blank control. The biodegradability of substituted phenols was expressed as BODT and the DO concentrations were determined by the iodometric titration method. Results The BODT and toxicity（log 1/IC50） of 12 substituted phenols to bacteria from the Songhua River were determined respectively. The correlation of biodegradability with toxicity was developed： BODT=8.21 （±2.22） pKa -32.44 （±8.28） log 1/IC50 ＋89.04 （±38.20）, n=12, R^2=0.791, R^2（adj）=0.745, SE=9.134, F=17.066, P=0.001. Conclusion The BODT of substituted phenols was influenced by their toxicity and the ionization constant pKa. The stronger the toxicity, the less readily the compound was degraded by river bacteria. 展开更多
关键词 Biodegradability Toxicity Correlation Substituted phenols
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One-Pot Synthesis of Substituted Cyclohexanes from Condensation of Aldehyde and Methylketone 认领 引用 被引量：3
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作者 Yin, YG Cheung, KK Wong, WT 《Chinese Chemical Letters》 SCIE CAS 1998年第4期329-332,共4页
Three asymmetrically substituted cyclohexanes were prepared from one-pot reactions of aldehydes and methylketones, and the products were characterized by single crystal structure analysis, NMR spectroscopy and microan... Three asymmetrically substituted cyclohexanes were prepared from one-pot reactions of aldehydes and methylketones, and the products were characterized by single crystal structure analysis, NMR spectroscopy and microanalysis. 展开更多
关键词 Michael reaction intermolecular condensation substituted cyclohexane
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Quantitative Structure-activity Relationship(QSAR) Study of Toxicity of Substituted Aromatic Compounds to Photobacterium Phosphoreum 认领 引用 被引量：2
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作者 荆国华 李小林 周作明 《Chinese Journal of Structural Chemistry》 SCIE CAS 2010年第8期1189-1196,共8页
With the artificial neural network（ANN） method combined with the multiple linear regression（MLR）,based on a series of quantum chemical descriptors and molecular connectivity indexes,quantitative structure-activity... With the artificial neural network（ANN） method combined with the multiple linear regression（MLR）,based on a series of quantum chemical descriptors and molecular connectivity indexes,quantitative structure-activity relationship（QSAR） models to predict the acute toxicity（-lgEC50） of substituted aromatic compounds to Photobacterium phosphoreum were established.Four molecular descriptors that appear in the MLR model,namely,the second order valence molecular connectivity index（2XV）,the energy of the highest occupied molecular orbital（EHOMO）,the logarithm of n-octyl alcohol/water partition coefficient（logKow） and the Connolly molecular area（MA）,were inputs of the ANN model.The root-mean-square error（RMSE） of the training and validation sets of the ANN model are 0.1359 and 0.2523,and the correlation coefficient（R） is 0.9810 and 0.8681,respectively.The leave-one-out（LOO） cross validated correlation coefficient（Q L2OO） of the MLR and ANN models is 0.6954 and 0.6708,respectively.The result showed that the two methods are complementary in the calculations.The regression method gave support to the neural network with physical explanation,and the neural network method gave a more accurate model for QSAR.In addition,some insights into the structural factors affecting the acute toxicity and toxicity mechanism of substituted aromatic compounds were discussed. 展开更多
关键词 quantitative structure-activity relationship artificial neural network multiple linear regression acute toxicity substituted aromatic compounds
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