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Science china chemistry 2007年第5期50卷 629-637页

作者： liu jiangtao1,2. liu {2. & liu shaopu1 1 school of chemistry and chemical Engineering, southwest university, chongqing 400715, china 2.Department of chemistry, Fuling Normal university, chongqing 408000, china school of chemistry and {2. Engineering Southwest UniversityChongqing400715China Department of chemistry Fuling Normal UniversityChongqing 408000China

The interaction of bleomycinA5 with nucleic acids has been investigated byusing resonance Rayleigh scattering (RRS),molecular absorption and fluorescence *** resultshows that in near pH 2.2.buffer medium and absence of any metal ions,nucleic acids are capable ofbinding with bleomycinA5 (BLMA5) to form complexes which can remarkably enhance the RRS intensityand result in batho-chromic and hyperchromic molecular absorption of nucleic acids and fluorescencequenching of *** RRS spectral characteristics for the binding products of bleomycinA5with various DNA and RNA are similar,and the maximum RRS peaks are at 301 nm for ctDNA and sDNA,370nm for hsDNA,310 nm for RNAtypeVI and RNAtypelll,*** increments of RRS intensity aregreatly different in which DNA enhances greatly and RNA enhances *** this work,the optimumconditions of the interaction and some influencing factors have been *** reactionmechanism and a binding model for the interaction of BLMA5 with the nucleic acids are ***,a highly sensitive,simple and rapid new method for the determination of DNA has *** detection limits (3 sigma) are 5.7 ng/mL for ctDNA,7.4 ng/mL for sDNA and 9.2.ng/mLfor hsDNA,*** method can be applied to determination of trace amounts of DNA.

关键词： bleomycinA5, nucleic acids, resonance Rayleigh scattering, fluorescence quenching, absorption spectrum.

The resonance Rayleigh scattering of the interaction of copper(Ⅱ)-bleomycinA2.with DNA and its analytical application

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Science china chemistry 2010年第3期53卷 618-624页

作者： liu jiangtao1,liu {2.2.& liu zhongfang2.1school of chemistry,chongqing Normal university,chongqing 400300,china 2.5} of chemistry and chemical Engineering,southwest university,chongqing 400715,china school of chemistry Chongqing Normal University Chongqing China school of chemistry and {2. Engineering Southwest University Chongqing China

The forming of bleomycinA2.Cu(Ⅱ) cationic chelate and the interaction of the chelate with DNA have been investigated by using resonance Rayleigh scattering(RRS),molecular absorption and fluorescence *** result shows that in aqueous solution,bleomycinA2.BLMA2. can react with Cu(Ⅱ) to form 1:1 cationic chelate which contributes to the changes of the absorption spectra and the quenched fluorescence of *** the cationic chelate further bound with DNA to form ternary ion-association complexes,the remarkable enhancement of the RRS intensity was *** this work,the optimum conditions for the coordination reaction of BLMA2.with Cu(Ⅱ) and some influencing factors have been *** reaction mechanism of BLMA2.Cu(Ⅱ) binding with DNA was suggested and a binding model was *** addition,the fluorescence quenching type of BLMA2.was investigated.A highly sensitive,simple and rapid new method for the determination of DNA by using BLMA2.Cu(Ⅱ) as RRS probe has been *** detection limits(3σ) are 7.2.ng/mL for ctDNA,7.1 ng/mL for sDNA and 18 ng/mL for *** method can be applied to the determination of trace amounts of DNA.

关键词： bleomycinA2 Cu(Ⅱ) DNA resonance Rayleigh scattering fluorescence quenching

Optimized the vanadium electrolyte with sulfate-phosphoric mixed acids to enhance the stable operation at high-temperature

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Frontiers of chemical Science and Engineering 2024年第2期18卷 13-26页

作者： Ling Ge Tao liu Yimin Zhang Hong liu school of Resource and Environmental Engineering Wuhan University of Science and TechnologyWuhan 430081China State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control Wuhan University of Science and TechnologyWuhan 430081China Hubei Collaborative Innovation Center for High Efficient Utilization of Vanadium Resources Wuhan University of Science and TechnologyWuhan 430081China Hubei Provincial Engineering Technology Research Center of High Efficient Cleaning Utilization for Shale Vanadium Resource Wuhan University of Science and TechnologyWuhan 430081China school of Resource and Environmental Engineering Wuhan University of TechnologyWuhan 430070China

Herein, the influence of the concentration design and comprehensive performance of the sulfate-phosphoric mixed acid system electrolyte is investigated to realize an electrolyte that maintains high energy density and stable operation at high temperatures. Static stability tests have shown that VOPO4 precipitation occurs only with vanadium(V) electrolyte. The concentration of vanadium ion of 2.0–2.2.mol·L^(–1), phosphoric acid of 0.10–0.15 mol·L^(–1), and sulfuric acid of 2.5–3.0 mol·L^(–1) are suitable for a vanadium redox flow battery in the temperature range from –2. to 50 ℃. The equations for predicting the viscosity and conductivity of electrolytes are obtained by the response surface method. The optimized electrolyte overcomes precipitation generation. It has 2.8 times higher energy density than the non-phosphate electrolyte, and a coulomb efficiency of 94.0% at 50 ℃. The sulfate-phosphoric mixed acid system electrolyte promotes the electrode reaction process, increases the current density, and reduces the resistance. This work systematically optimizes the concentrations of composition of positive and negative vanadium electrolytes with mixed sulfate-phosphoric acid. It provides a basis for the different valence states and comprehensive properties of sulfate-phosphoric mixed acid system vanadium electrolytes under extreme environments, guiding engineering applications.

关键词： all vanadium redox flow battery mixed-acid vanadium electrolyte concentration optimization response surface methodology high-temperature stability

The interaction between furosemide-palladium (Ⅱ) chelate and basic triphenylmethane dyes by resonance Rayleigh scattering spectra and resonance non-linear scattering spectra and their analytical applications

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Science china chemistry 2010年第8期53卷 1767-1777页

作者： LI CuiXia,liu shaopu,liu zhongfang & HU XiaoLi Key Laboratory on Luminescence and Real-Time Analysis,Ministry of Education school of chemistry and chemical Engineering,southwest university,chongqing 400715,{12. Key Laboratory on Luminescence and Real-Time Analysis Ministry of Education school of chemistry and {2. Engineering Southwest University Chongqing China

In pH 4.5-7.0 Britton-Robinson buffer solution,furosemide (FUR) reacted with Pd (II) to form a 1:1 anionic *** chelate could further react with such basic triphenylmethane dyes (BTPMD) as ethyl violet (EV),crystal violet (CV),methyl violet (MV),methyl green (MeG) and brilliant green (BG) to form 1:1 ion-association *** not only resulted in the change of absorption spectra,but also led to the significant enhancement of resonance Rayleigh scattering (RRS),second-order scattering (SOS) and frequency doubling scattering (FDS).The maximum RRS wavelengths were located at 32. nm for the EV,CV and MV system,and 340 nm for the BG and MeG *** maximum SOS wavelengths were located at 550 nm for the EV,CV,BG and MeG system,and 530 nm for the MV *** maximum scattering peaks of all the systems were at 392.nm for *** enhanced RRS,SOS and FDS intensities were directly proportional to the concentration of *** detection limits for the different dye systems were 0.3-4.9 ng mL-1 for the RRS method,3.2.33.1 ng mL-1 for the SOS method and 9.0-85.7 ng mL-1 for the FDS *** methods could be used for the determination of trace amounts of *** effects of the formation of ternary ion-association complexes on the spectral characteristics and intensities of absorption,RRS,SOS and FDS have been *** optimum conditions of these reactions,the influencing factors and the analytical properties have been *** influences of coexisting substances were tested by RRS method and the results showed that this method exhibited a high *** on the aforementioned research,the highly sensitive,simple and rapid methods for the determination of trace amounts of FUR by resonance light scattering technique have been established,which could be applied to the determination of FUR in tablet,injection,human serum and urine *** composition and structure of the ternary ion-association complex and the reaction mechanism were discusse

关键词： furosemide basic triphenylmethane dyes palladium (Ⅱ) resonance Rayleigh scattering resonance non-linear scattering

A combinatorial synthesis method for identification of orally bioavailable cyclic peptide

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Science china chemistry 2024年第8期67卷 2429-2430页

作者： Zhenzhen liu Li liu Bo Tang College of chemistry Chemical Engineering and Materials ScienceKey Laboratory of Molecular and Nano ProbesMinistry of EducationCollaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of ShandongInstitutes of Biomedical SciencesShandong Normal UniversityJinan 250014China Laoshan Laboratory Qingdao 266237China

Cyclic peptides are a type of polypeptide with macrocyclic structure formed by canonical and non-canonical amino *** to their rigid conformation and large surface area,cyclic peptides typically exhibit high binding affinity and specificity with target proteins,particularly those considered undruggable by traditional small molecule drugs,such as protein-protein interactions[1].Additionally,they are convenient to be chemical modified to improve the pharmacological or pharmacokinetic properties.

关键词： properties. canonical synthesis

Enlarged interlayer of separator coating enabling high-performance lithiumsulfur batteries

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Frontiers of chemical Science and Engineering 2024年第2期18卷 103-112页

作者： Yanqi Feng Hui liu Xiaoting liu Qiongqiong Lu school of Materials&Environment Engineering Chengdu Technological UniversityChengdu 611730China school of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi’an 710021China Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450001China Institute of Materials Henan Key Laboratory of Advanced Conductor MaterialsHenan Academy of SciencesZhengzhou 450046China Leibniz Institute for Solid State and Materials Research(IFW) Dresden e.V.Dresden 01069Germany

Lithiumsulfur batteries have been intensively studied due to their high theoretical energy density and abundant sulfur resources. However, their commercial application is hindered by the low redox kinetics and high sulfur losses. In principle, in the design of cathodes and separators, the adsorption toward lithium-polysulfides should be enhanced and the conversion of soluble high-order lithium-polysulfides should be catalyzed. Herein, a KV_(3)O_(8)·0.75H_(2.O separator is designed as an effective lithium-polysulfides mediator in lithiumsulfur batteries. The intercalated K+ would enlarge the interlayer spacing of vanadium oxides, preventing the collapse of the layer structure and improving the electrical/ion conductivity of the interface. Moreover, the KV_(3)O_(8)·0.75H_(2.O modified separator possess a prior adsorption and high redox kinetics toward lithium-polysulfides due to the enhanced diffusion kinetics, which guarantees the high-rate capability and efficient utilization of sulfur. As a result, lithiumsulfur batteries exhibit a high capacity of 1362.mAh·g^(-1) and a long lifespan with a low capacity loss of 0.073% per cycle. This work may provide an alternative way to establish a functional separator to balance the adsorption and conversion of polysulfides during the redox back and forth.

关键词： lithium kinetics adsorption

High-performance nickel metal hydride battery anode with enhanced durability and excellent low-temperature discharge capability

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Nano Research 2024年第10期17卷 8819-8825页

作者： Zhitao Chen Huitian liu Jean Nei Nian liu school of chemical and Biomolecular Engineer{2. Georgia Institute of TechnologyAtlantaGA 30332USA GP Batteries HongkongChina

Current AB_(5)-type hydrogen storage alloys employed in nickel-metal hydride(NiMH)batteries exhibit exceptional low-temperature discharge performance but suffer from limited cycle life and insufficient high-temperature *** overcome these challenges,we introduce a hydrothermal synthesized LaF_(3)coating layer on the surface of the AB_(5)anode *** LaF_(3)coating layer adds a protective barrier for the active material,significantly improving the battery's cycle life and high-temperature *** findings indicate that(1)the LaF_(3)coated anode demonstrates an extended cycle life with increased specific capacity and a capacity retention of 88%after 40 cycles of abusive overcharging and rapid discharging at room temperature.(2.The synthesized anode exhibits a 97%recovery of its specific capacity of 2.2.7 mAh/g following 144 h of high-temperature storage.(3)The low-temperature discharge capacity of the synthesized anode remains on par with the pristine AB_(5)alloy at 2.0.4 mAh/g in a-40℃*** research presents a significant advancement in hydrogen storage alloy coatings and offers valuable insights for designing electrodes in NiMH batteries.

关键词： nickel metal hydride(NiMH)batteries hydrothermal synthesis lanthanum fluoride discharge capacity low temperature

Shock Raman spectra and structural transformation of powdered TKX-50 by the plate impact experiments combined with real-time Raman detection

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Defence Technology（防务技术） 2024年第1期31卷 158-162页

作者： Xue Yang Qijun liu Yundan Gan Lei Yang Zhengtang liu Fusheng liu Bond and Band Engineering Group School of Physical Science and TechnologySouthwest Jiaotong UniversityChengdu 610031People's Republic of China Xi'an Modern chemistry Research Institute Xi'an 710065People's Republic of China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072People's Republic of China

As an energetic material of great interest,the work capacity of dihydroxylammonium 5,5’-bistetrazole-1,1’-diolate(TKX-50)has been questioned *** some research groups have explored the reasons for the low working ability of TKX-50,the plane impact experiment on powdered TKX-50 is obviously closer to the practical application,and the conclusions based on this are more ***,we performed shock Hugoniot measurements of powdered TKX-50 between 5.65 and 16.2. *** plane impact experiments of powdered TKX-50 were carried out and the shocked Raman spectra were *** Raman spectroscopy analysis,a new peak of powdered TKX-50 was found between19.47 GPa and 2..96 GPa,which may be caused by decomposition/phase transition and was related with the low work capacity.

关键词： Powdered TKX-50 Hugoniot Raman Decomposition Phase transition

Polyimide covalent organic frameworks as efficient solid-state Li^(+) electrolytes

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Science china chemistry 2024年第5期67卷 1647-1652页

作者： Xu liu Shi Wang Siqi liu Chengfang liu Xiangchun Li Jian Wu Dazhi Li Shihao Xu Chongyang liu Wen-Yong Lai State Key Laboratory of Organic Electronics and Information Displays(SKLOEID) Institute of Advanced Materials(IAM)School of Chemistry and Life SciencesNanjing University of Posts&TelecommunicationsNanjing 210023China

Covalent organic frameworks(COFs) are attractive porous crystalline materials with extremely high stability, easy functionalization, and open channels, which are expected to be unique ion conductors/transporters in lithium ion batteries(LIBs). Despite recent advances, low ion conductivity and low transference number, resulting in low charging/discharging rate, low energy density, and short battery life, are the main issues that limit their direct application as solid electrolytes in LIBs. Here, we designed and synthesized a novel polyimide COF, namely, TAPA-PDI-COF, with abundant C=O groups, which has been successfully employed as high-performance solid electrolytes by doping TAPA-PDI-COF and succinonitrile(SN). Both the well-defined nanochannels of COFs and SN confined in the well-aligned channels restricted the free migration of anions, while C=O on COFs and CN groups of SN enhanced Li^(+) transport, thus achieving a high ion conductivity of 0.102.m S cm^(-1)at 80 °C and a high lithium-ion transference number of 0.855 at room temperature. According to density functional theory(DFT)calculations, Li-ion migration mainly adopted in-plane transport rather than the axial pathway, which may be due to the shorter hopping distances in the planar pathway. The results suggest an effective strategy for the design and development of all-solidstate ionic conductors for achieving high-performance LIBs.

关键词： lithium ion batteries(LIBs) covalent organic frameworks(COFs) solid-state ion conductors solid-state electrolytes ion conductivity

Asymmetrically coordinated single atom Cu catalyst with unsaturated C-Cu-N structure for CO_(2. reduction to CO

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Nano Research 2024年第5期17卷 3911-3918页

作者： Zheng liu Yuxuan liu J{2.qiao Zhang T{2. Cao Zhiyi Sun Juzhe liu Huishan Shang State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China SEPA Key Laboratory of Eco-Industry Chinese Research Academy of Environmental SciencesBeijing 100012China The Key Laboratory of Resources and Environmental System Optimization Ministry of EducationCollege of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China school of chemical Engineer{2. Zhengzhou UniversityZhengzhou 450001China

Single atom catalysts(SACs)play a crucial role in energy catalysis due to their distinct coordination environment and high atomic utilization *** study focuses on the synthesis of a monatomic Cu catalyst with Cu-N1C1 coordination anchored to N-doped Ti_(3)C_(2.T_(x) MXene(Cu SA@N-Ti_(3)C_(2.T_(x))to achieve efficient reduction of CO_(2. to *** characterization,including morphology and multispectral analysis,confirmed the uniform distribution of asymmetrically coordinated Cu atoms in unsaturated C-Cu-N bridge fragments on Ti_(3)C_(2.T_(x).The Cu SA@N-Ti_(3)C_(2.T_(x) catalyst exhibited an excellent CO selectivity with Faraday efficiency of 97.4%at-0.58 V *** hydrogen electrode(RHE)and satisfactory *** in situ X-ray absorption fine structure(XAFS)results confirmed that the carbon dioxide reduction reaction(CO_(2.RR)product distribution is mainly affected by potential-dependent valence change of Cu *** findings highlight the extensive potential of tuning coordination structure of MXene-based single-atom catalysts for CO_(2. reduction reactions.

关键词： cooper single atom atomic regulation MXene Ti_(3)C_(2.T_(x) CO_(2.reduction