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Integrating controlled synthesis and theory for revealing of active site structure of single-atom nickel catalysts in electrochemical CO_(2)reduction
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作者 Yuxing Xu Leilei Wang +8 位作者 Qin Liu Botao Teng Chuanqiang Wu Binghui Ge Wentuan Bi Minghui Gu Mengkai Zhang Huan Yan Junling Lu 《Chinese Journal of Catalysis》 2025年第12期68-77,共10页
Electrocatalytic conversion of carbon dioxide(CO_(2))offers an effective method of CO_(2)fixation to mitigate global warming and the energy crisis.However,for supported Ni single-atom catalysts(SACs),which are among t... Electrocatalytic conversion of carbon dioxide(CO_(2))offers an effective method of CO_(2)fixation to mitigate global warming and the energy crisis.However,for supported Ni single-atom catalysts(SACs),which are among the most promising candidates for this application,the relationship between Ni coordination structure and catalytic properties is still under strong debate.Here,we fabricated a series of Ni SACs through precise-engineering of anchor sites on nitrogen-doped carbon(NC)followed by Ni atom anchoring using atomic layer deposition.Among them,a Ni_(1)/NC SAC,with a coordination number(CN)of four but less pyridinic nitrogen(N_(pyri)),achieved over 90%faradaic efϐiciency for CO at potentials from-0.7 to-1.0 V and a mass activity of 6.5 A/mgNi at-0.78 V along with high stability,outperforming other Ni SACs with lower CN and more N_(pyri).Theoretical calculations of various three and four-coordinated Ni_(1)-NxCy structures revealed a linear correlation between the reaction Gibbs free energy for the potential-limiting step and the highest occupied molecular orbital(HOMO)position of Ni-3d orbitals,therein the four-coordinated Ni_(1)-N_(1)C_(3)with the highest HOMO position is identified as the active site for the electrocatalytic CO_(2)-to-CO process,in line with the experimental results. 展开更多
关键词 Single-atom catalyst Ni_(1)/NC Coordination structure regulation Active site structure Electrochemical CO_(2)reduction
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Silver‑doped antimicrobial fluorescent carbon dots:Dual properties of metal ion detection and antibacterial
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作者 LU Jiaxin QIAO Yifu +3 位作者 QIANG Xing GAO Yong LIU Ziya ZHANG Manying 《无机化学学报》 北大核心 2026年第2期398-412,共15页
Herein,antibacterial silver‑doped fluorescent carbon dots(Ag‑CDs)were synthesized through a stepwise hydrothermal method,with polyethyleneimine(PEI),citric acid(CA),and silver nitrate(AgNO3)serving as precursors.The a... Herein,antibacterial silver‑doped fluorescent carbon dots(Ag‑CDs)were synthesized through a stepwise hydrothermal method,with polyethyleneimine(PEI),citric acid(CA),and silver nitrate(AgNO3)serving as precursors.The applicability and antimicrobial efficacy of these nanomaterials were systematically investigated for metal ion sensing.Experimental evidence demonstrated that the Ag‑CDs exhibited a pronounced fluorescence quenching response toward ferric ions(Fe^(3+)),enabling their quantitative determination via a linear concentration‑dependent relationship.These Ag‑CDs exhibited significant inhibitory effects on biofilm growth and disruption for both Escherichia coli and Staphylococcus aureus.Mechanism investigations indicate that Ag‑CDs induced the death of Escherichia coli and Pseudomonas aeruginosa by disrupting their bacterial morphology and structure,triggering the generation of intracellular reactive oxygen species(ROS),and impairing their antioxidant defense system. 展开更多
关键词 silver‑doped carbon dots fluorescence property Fe3+selective response antibacterial property
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Direct UV photolysis of cloperastine in aqueous solution:Kinetic model and degradation pathwa
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作者 Marc Marín-García Rafael Gonzalez-Olmos Cristian Gómez-Canela 《Journal of Environmental Sciences》 2026年第1期670-682,共13页
The increasing production and release of synthetic organic chemicals,including pharmaceuticals,into our envi-ronment has allowed these substances to accumulate in our surface water systems.Current purification technol... The increasing production and release of synthetic organic chemicals,including pharmaceuticals,into our envi-ronment has allowed these substances to accumulate in our surface water systems.Current purification technolo-gies have been unable to eliminate these pollutants,resulting in their ongoing release into aquatic ecosystems.This study focuses on cloperastine(CPS),a cough suppressant and antihistamine medication.The environmental impact of CPS usage has become a concern,mainly due to its increased detection during the COVID-19 pandemic.CPS has been found in wastewater treatment facilities,effluents from senior living residences,river waters,and sewage sludge.However,the photosensitivity of CPS and its photodegradation profile remain largely unknown.This study investigates the photodegradation process of CPS under simulated tertiary treatment conditions using UV photolysis,a method commonly applied in some wastewater treatment plants.Several transformation prod-ucts were identified,evaluating their kinetic profiles using chemometric approaches(i.e.,curve fitting and the hard-soft multivariate curve resolution-alternating least squares(HS-MCR-ALS)algorithm)and calculating the reaction quantum yield.As a result,three different transformation products have been detected and correctly identified.In addition,a comprehensive description of the kinetic pathway involved in the photodegradation process of the CPS drug has been provided,including observed kinetic rate constants. 展开更多
关键词 Cloperastine UV photolysis UHPLC-QTOF-MS/MS Kinetic model Degradation pathway Hard-soft multivariate curve resolution-alternating least squares (HS-MCR-ALS)
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Recent advances on micro-polluted water remediation by full-scale constructed wetlands:Pollutant removal performance,key influencing factors,and enhancing strategies
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作者 Qiang Ning Peihao Yan +4 位作者 Lingyan Zhao Zhiyi Lin Jian Zhang Zizhang Guo Haiming Wu 《Journal of Environmental Sciences》 2026年第1期565-576,共12页
The discharge of micro-polluted water from sources such as agricultural runoff,urban stormwater,and treated effluents presents significant challenges to aquatic ecosystems.Constructed wetlands(CWs)have gained recog-ni... The discharge of micro-polluted water from sources such as agricultural runoff,urban stormwater,and treated effluents presents significant challenges to aquatic ecosystems.Constructed wetlands(CWs)have gained recog-nition as an eco-friendly solution for removing pollutants from various wastewater sources and are increasingly applied for micro-polluted water treatment.By reviewing 78 full-scale CW studies from Web of Science,it is summarized that the ranges of ammonium nitrogen(NH4+-N)concentrations in runoff,wastewater treatment plant effluent and polluted river were 0.1–6.6,0.3–12.3,and 0.2–41.1 mg/L,respectively.The ranges of ni-trate nitrogen concentrations were 0.2–14.2,0–5.7,and 0–2.6 mg/L,respectively.Removal efficiencies of CWs for micro-polluted water varied by CW types.The total nitrogen removal efficiencies for subsurface-flow CWs,free-water surface-flow CWs,and hybrid CWs ranged from 27.4%to 66.5%,16.8%to 89.8%,and 19.4%to 88.2%,respectively.The NH4+-N removal efficiencies ranged from 34.2%to 73.6%,38.4%to 89.4%and 13.5%to 94.2%,respectively.Additionally,other factors influencing contaminant removal efficiency such as hydraulic retention time,vegetation types,redox micro-environment and influent water quality were evaluated.Based on these findings,two strategies for improving the purification performance of CWs were proposed:the selection of incorporating electron donor substrates and the optimization of operation parameters.This paper serves as a synthesis of information to guide future research and full-scale CW applications in micro-polluted water treatment. 展开更多
关键词 Constructed wetlands Micro-polluted water Nutrient removal Influencing factors Enhancing strategies
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3D printing biomimeticmaterials and structures for biomedical applications 被引量:10
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作者 Yizhen Zhu Dylan Joralmon +5 位作者 Weitong Shan Yiyu Chen Jiahui Rong Hanyu Zhao Siqi Xiao Xiangjia Li 《Bio-Design and Manufacturing》 SCIE EI CSCD 2021年第2期405-428,共24页
Over millions of years of evolution,nature has created organisms with overwhelming performances due to their unique materials and structures,providing us with valuable inspirations for the development of next-generati... Over millions of years of evolution,nature has created organisms with overwhelming performances due to their unique materials and structures,providing us with valuable inspirations for the development of next-generation biomedical devices.As a promising new technology,3D printing enables the fabrication of multiscale,multi-material,and multi-functional threedimensional(3D)biomimetic materials and structures with high precision and great flexibility.The manufacturing challenges of biomedical devices with advanced biomimetic materials and structures for various applications were overcome with the flourishing development of 3D printing technologies.In this paper,the state-of-the-art additive manufacturing of biomimetic materials and structures in the field of biomedical engineering were overviewed.Various kinds of biomedical applications,including implants,lab-on-chip,medicine,microvascular network,and artificial organs and tissues,were respectively discussed.The technical challenges and limitations of biomimetic additive manufacturing in biomedical applications were further investigated,and the potential solutions and intriguing future technological developments of biomimetic 3D printing of biomedical devices were highlighted. 展开更多
关键词 3D printing BIOPRINTING Biomimetic material Functional structures Biomedical applications
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Titanium-Containing Mesoporous Materials: Synthesis and Application in Selective Catalytic Oxidation 被引量:2
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作者 Jie Li Chunhui Zhou Huali Xie Zhonghua Ge Liangcai Yuan Xiaonian Li 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2006年第3期164-177,共14页
Titanium-containing mesoporous molecular sieves are of great significance in selective catalytic oxidation processes with bulky molecules. Recent researches and developments on the designing and synthesis of Ti-contai... Titanium-containing mesoporous molecular sieves are of great significance in selective catalytic oxidation processes with bulky molecules. Recent researches and developments on the designing and synthesis of Ti-containing mesoporous materials have been reviewed. Various strategies for the preparation of Ti-containing mesoporous materials, such as direct synthesis and post-synthesis, are described. Modifications of Ti-containing mesoporous materials by surface-grafting and atom-planting are also discussed. All approaches aimed mainly at the improving of the stability, the hydrophobicity, and mostly the catalytic activity. Structural and mechanistic features of various synthetic systems are discussed. Ticontaining mesoporous materials in liquid phase catalytic oxidation of organic compounds with H2O2 as an oxidant is briefly summarized, showing their broad utilities for green synthesis of fine chemicals by catalytic oxidative reactions. 展开更多
关键词 mesoporous materials TITANIUM molecular sieve zeolites CHARACTERIZATION catalytic oxidation
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Structural modulation of anthraquinone with different functional groups and its effect on electrochemical properties for lithium-ion batteries 被引量:2
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作者 QIAN Su-hui PAN Jun-xian +6 位作者 ZHU Zhao-sheng YE Rui-tian LIN Geng-zhong ZHU Xiao-xing XIONG Zhi-yong ZENG Rong-hua LUO Yi-fan 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第6期1449-1457,共9页
Organic electrode materials have high capacity,and environmentally friendly advantages for the next generation lithium-ion batteries(LIBs).However,organic electrode materials face many challenges,such as low reduction... Organic electrode materials have high capacity,and environmentally friendly advantages for the next generation lithium-ion batteries(LIBs).However,organic electrode materials face many challenges,such as low reduction potential as cathode materials or high reduction potential as anode materials.Here,the influence of chemical functionalities that are capable of either electron donating or electron withdrawing groups on the reduction potential and charge-discharge performance of anthraquinone(AQ)based system is studied.The cyclic voltammetry results show that the introduction of two-OH groups,two-NO2 groups and one-CH3 group on anthraquinone structure has a little impact on the reduction potential,which is found to be 2.1 V.But when three or four-OH groups are introduced on AQ structure,the reduction potential is increased to about 3.1 V.The charge-discharge tests show that these materials exhibit moderate cycling stability. 展开更多
关键词 lithium-ion batteries ANTHRAQUINONE electron groups reduction potential
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Synthesis and Characterization of Novel Layered Lithium Sodium Silicate (Silinaite) and the Mesoporous Materials from Silinaite 被引量:1
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作者 Chun Hui ZHOU Hong Qiang GUO Hui Jun CAO Xiao Nian LI Zhong Hua GE Jie LI 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第4期525-528,共4页
Novel layered silinaite has been synthesized using an aqueous mixture of water glass, LiOH and NaOH under hydrothermal crystallization. Subsequently transformation of silinaite into mesoporous materials (SDM) was ac... Novel layered silinaite has been synthesized using an aqueous mixture of water glass, LiOH and NaOH under hydrothermal crystallization. Subsequently transformation of silinaite into mesoporous materials (SDM) was achieved at mild condition using cetyltfimethylammonium bromide as structure-directing agents. The resulting samples were characterized by XRD, SEM, FTIR nitrogen adsorption-desorption isotherms and catalytic performance in bulky molecular involved reaction. The results revealed that synthesized mesoporous materials derived from the silinaite exhibited an ordered hexagonal crystal structure with average pore diameter 2.7 nm and BET surface area 817m^2/g. The SDM-supported ZnCl2 catalyst, prepared by impregnationevaporation method, retained the mesoporous structure and showed high selectivity in alkylation of benzene with benzyl chloride. 展开更多
关键词 Silinaite mesoporous materials layered solid CATALYSTS characterization.
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Fabrication of polypyrrole/TiO_2 nanocomposite via electrochemical process and its photoconductivity 被引量:1
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作者 欧阳密 白茹 +4 位作者 徐意 张诚 马淳安 汪茫 陈红征 《中国有色金属学会会刊:英文版》 EI CSCD 2009年第6期1572-1577,共6页
Size-controllable and vertically-oriented TiO2 nanotube(TNT)arrays were fabricated using anodic oxidation method from pure titanium sheets in electrolyte solutions.Then with the TNT arrays as the working electrode,a t... Size-controllable and vertically-oriented TiO2 nanotube(TNT)arrays were fabricated using anodic oxidation method from pure titanium sheets in electrolyte solutions.Then with the TNT arrays as the working electrode,a thin film of polypyrrole(Ppy)was synthesized into the TNT arrays via the electrochemical polymerization.During the process,the appearance of redox peaks in cyclic voltammetry curves of the resulting films indicates the occurrence of polymerization.The morphology,the molecular structure, crystallization and optical properties of the TNT arrays and the resulting polymer were investigated by field-emission scanning electron microscopy(FESEM),X-ray diffractometry(XRD),Fourier transform infrared spectroscopy(FTIR),and UV-vis spectrum analysis,respectively.A dual-layered photoreceptor containing the nanocomposite film as the charge generation layer(CGL)was designed and fabricated.It is found that the photoreceptor based on Ppy/TiO2 nanotubes as CGL exhibits remarkable photoconductive performance. 展开更多
关键词 TIO2纳米管 复合材料制备 电化学过程 光电导 傅立叶变换红外光谱 纳米复合薄膜 TNT炸药 电化学聚合
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Comparative Study of the Structure and Properties of Ti—O-based Nanowire Films Prepared by Anodization and Chemical Oxidation Methods
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作者 Xinwen Huang Zongjian Liu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2014年第9期878-883,共6页
Net-like titanium oxide or H-titanate nanowire films were grown on Ti substrates in 2 mol/L NaOH solutions at 80 ℃ via anodization method or chemical oxidation followed by proton-exchange. The microstructure, thermal... Net-like titanium oxide or H-titanate nanowire films were grown on Ti substrates in 2 mol/L NaOH solutions at 80 ℃ via anodization method or chemical oxidation followed by proton-exchange. The microstructure, thermal stability and photoelectrochemical property of two types of films were investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and photocurrent measurement. It is found that the anodic film mainly consists of a 500-nm-thick nenowire layer whereas the film formed by chemical oxidization is made up of two layers: a nanowire layer (nearly 1 tim in thickness) and an underlying non- nanowire layer (at least 1 μm in thickness). In both two cases, the as-formed nanowires are partly crystallized. Thermal stability investigation reveals that the net-like structure of the anodic nanowire film almost keeps unchanged at a temperature less than 400℃ but is totally destroyed when being calcinated at 600 ℃. In contrast, the nanowire layer formed by chemical method is stable even after being calcinated at 600 ℃. Our results also show that the uncalcinated or calcinated anodic films are much more photoactive than the corresponding films prepared by chemical oxidization. The difference in photoelectrochemical property of two types of films is discussed based on their microstructures. 展开更多
关键词 Anodization NANOWIRES Thin films Titanium dioxide TITANATE
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Simultaneous photoelectrochemical detection of dual microRNAs by capturing CdS quantum dots and methylene blue based on target-initiated strand displaced amplification
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作者 Jiafu Chang Wenxin Lv +2 位作者 Jiahui Wu Haiyin Li Feng Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第2期775-778,共4页
Herein,we propose a novel photoelectrochemical(PEC) biosensor for dual microRNAs(miRNAs) highly sensitive and simultaneous biosensing based on strand displaced amplification(SDA) reaction.The recognition of HmiR-21 an... Herein,we propose a novel photoelectrochemical(PEC) biosensor for dual microRNAs(miRNAs) highly sensitive and simultaneous biosensing based on strand displaced amplification(SDA) reaction.The recognition of HmiR-21 and Hlet-7 a by microRNA-21 and let-7 a leads to their change in hairpin structures,subsequently initiating the immobilization of abundant CdS quantum dots(CdS QD s) and methylene blue(MB) based on SDA reaction.The immobilized CdS QDs and MB produce both high PEC currents under430 nm light and 627 nm light illumination,respectively,and the generated PEC currents are closely relied on target miRNAs amounts.Thus,highly sensitive and simultaneous detection of microRNA-21 and let-7 a was readily achieved with detection limit at 6.6 fmol/L and 15.4 fmol/L based on 3σ,respectively.Further,this PEC biosensor was applied in simultaneous analysis of miRNA-21 and let-7 a in breast cancer patient’s serum with acceptable results.We expect this biosensor will find more useful application in diagnosis of miRNA-related diseases. 展开更多
关键词 PEC CdS QDs Methylene blue Multiple microRNAs Strand displaced amplification Simultaneous biosensing
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Influences of Sintering Process of Sprayed Precursors on the Struc-ture and Electrochemical Properties of LiMn_2O_4 Cathode Material
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作者 Hui HUANG Chen WANG Lei ZHANG Yongping GAN Wenkui ZHANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2008年第2期211-214,共4页
Well-defined spinel LiMn2O4 powders were synthesized via sintering a precursor, which was prepared by spraydrying method. The effects of sintering process on the structure and electrochemical properties of LiMn2O4 wer... Well-defined spinel LiMn2O4 powders were synthesized via sintering a precursor, which was prepared by spraydrying method. The effects of sintering process on the structure and electrochemical properties of LiMn2O4 were discussed. It was found that a single sintering could not synthesize a pure LiMn2O4 compound, while two-step sintering procedure consisting of decomposing sprayed precursors at 350℃ and further sintering at an elevated temperature leads to the formation of a single-phased LiMn2O4 with homogeneous particle size distribution. As compared to that sintered in air, the two-step sintered LiMn2O4 in oxygen shows tighter structure and more uniform particle size, as well as better electrochemical properties. It delivers an initial discharge capacity of 131 mAh·g^-1 (1/10C), and still has excellent cycling stability at higher rate (1/5C). 展开更多
关键词 Spinel LiMn2O4 Spray-drying method Li-ion batteries SINTERING
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Tuning the Water Desalination Performance of Graphenic Layered Nanomaterials by Element Doping and Inter-Layer Spacing
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作者 Fuxin Wang Chao Zhang +4 位作者 Yanmei Yang Yuanyuan Qu Yong-Qiang Li Baoyuan Man Weifeng Li 《Chinese Physics Letters》 SCIE CAS CSCD 2020年第11期48-54,共7页
Through atomic molecular dynamics simulations,we investigate the performance of two graphenic materials,boron(BC3)and nitrogen doped graphene(C3 N),for seawater desalination and salt rejection,and take pristine graphe... Through atomic molecular dynamics simulations,we investigate the performance of two graphenic materials,boron(BC3)and nitrogen doped graphene(C3 N),for seawater desalination and salt rejection,and take pristine graphene as a control.Effects of inter-layer separation have been explored.When water is filtered along the transverse directions of three-layered nanomaterials,the optimal inter-layer separation is 0.7–0.9 nm,which results in high water permeability and salt obstruction capability.The water permeability is considerably higher than porous graphene filter,and is about two orders of magnitude higher than commercial reverse osmosis(RO)membrane.By changing the inter-layer spacing,the water permeability of three graphenic layered nanomaterials follows an order of C3 N≥GRA>BC3 under the same working conditions.Amongst three nanomaterials,BC3 is more sensitive to inter-layer separation which offers a possibility to control the water desalination speed by mechanically changing the membrane thickness.This is caused by the intrinsic charge transfer inside BC3 that results in periodic distributed water clusters around the layer surface.Our present results reveal the high potentiality of multi-layered graphenic materials for controlled water desalination.It is hopeful that the present work can guide design and fabrication of highly efficient and tunable desalination architectures. 展开更多
关键词 SEPARATION LAYER filtered
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Design and manufacturing of soft electronics for in situ biochemical sensing
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作者 Yi Xing Jiaqi Wang Jinxing Li 《International Journal of Extreme Manufacturing》 CSCD 2024年第6期137-167,共31页
Soft(flexible and stretchable) biosensors have great potential in real-time and continuous health monitoring of various physiological factors, mainly due to their better conformability to soft human tissues and organs... Soft(flexible and stretchable) biosensors have great potential in real-time and continuous health monitoring of various physiological factors, mainly due to their better conformability to soft human tissues and organs, which maximizes data fidelity and minimizes biological interference.Most of the early soft sensors focused on sensing physical signals. Recently, it is becoming a trend that novel soft sensors are developed to sense and monitor biochemical signals in situ in real biological environments, thus providing much more meaningful data for studying fundamental biology and diagnosing diverse health conditions. This is essential to decentralize the healthcare resources towards predictive medicine and better disease management. To meet the requirements of mechanical softness and complex biosensing, unconventional materials, and manufacturing process are demanded in developing biosensors. In this review, we summarize the fundamental approaches and the latest and representative design and fabrication to engineer soft electronics(flexible and stretchable) for wearable and implantable biochemical sensing. We will review the rational design and ingenious integration of stretchable materials, structures, and signal transducers in different application scenarios to fabricate high-performance soft biosensors. Focus is also given to how these novel biosensors can be integrated into diverse important physiological environments and scenarios in situ, such as sweat analysis, wound monitoring, and neurochemical sensing. We also rethink and discuss the current limitations,challenges, and prospects of soft biosensors. This review holds significant importance for researchers and engineers, as it assists in comprehending the overarching trends and pivotal issues within the realm of designing and manufacturing soft electronics for biochemical sensing. 展开更多
关键词 soft materials processing and fabrication biochemical sensing electrode fabrication transducer integration
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Functional design and understanding of effective additives for achieving high-quality perovskite films and passivating surface defects 被引量:2
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作者 Fengwu Liu Jiacheng Xu +7 位作者 Yongchao Ma Yoomi Ahn Xiangrui Du Eunhye Yang Haicheng Xia Bo Ram Lee Pesi Mwitumwa Hangoma Sung Heum Park 《Journal of Energy Chemistry》 2025年第3期597-608,共12页
Achieving high-quality perovskite films without surface defects is regarded as a crucial target for the development of durable high-performance perovskite solar cells.Additive engineering is commonly employed to simul... Achieving high-quality perovskite films without surface defects is regarded as a crucial target for the development of durable high-performance perovskite solar cells.Additive engineering is commonly employed to simultaneously control the growth of perovskite crystals and passivate defects.Here,4-(trifluoromethyl)benzoic anhydride(4-TBA)composed of benzene rings functionalized with carbonyl and trifluoromethyl groups was used as an example additive to study the characteristics of additives used for producing high-quality perovskites and controlling their surface properties.The interaction between4-TBA and perovskite precursor materials was investigated using density functional theory(DFT)simulations.The electron-rich carbonyl group efficiently passivated the under-coordinated lead-ion defects.Additionally,hydrogen bonding between trifluoromethyl and organic cations prevents the generation of cation vacancies.Because of its intrinsic hydrophobicity,the trifluoromethyl group simultaneously improves the moisture and heat stability of the film.4-TBA serves as a universal modifier for various perovskite compositions.The power conversion efficiency(PCE)of inverted perovskite solar cells(PSCs)based on methylammonium(MA)with 4-TBA was improved from 16.15%to 19.28%.Similarly,the PCE of inverted PSCs based on a cesium formamidinium MA(CsFAMA)perovskite film increased from20.72%to 23.58%,upon addition of 4-TBA.Furthermore,the moisture and thermal stability of 4-TBAtreated films and devices was significantly enhanced,along with prolonged device performance.Our work provides guidance on selecting the structure and functional groups that are essential for surface defect passivation and the production of high-quality perovskites. 展开更多
关键词 Perovskite solar cells Regulated crystal growth Defect passivation 4-(trifluoromethyl)benzoic anhydride Perovskite stability
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Cu(Ⅱ) and Cu(Ⅰ) complexes based on derivatives of imidazo[1,5-a]pyridine:Synthesis,structures,in situ metal-ligand reactions,and catalytic activity
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作者 JIA Bofei LIU Zhihao +7 位作者 GAO Zongyuan ZHOU Shuai WU Mengxiang ZHANG Qian ZHANG Xiamei CHEN Shuzhong YANG Xiaohan LI Yahong 《无机化学学报》 北大核心 2025年第5期1020-1036,共17页
Three efficient methods for the synthesis of a series of Cu(Ⅱ) and Cu(Ⅰ) complexes based on imidazo[1,5-a]pyridine derivatives were developed.These methods include the following:(ⅰ)Cu(Ⅱ) salts were used as metal s... Three efficient methods for the synthesis of a series of Cu(Ⅱ) and Cu(Ⅰ) complexes based on imidazo[1,5-a]pyridine derivatives were developed.These methods include the following:(ⅰ)Cu(Ⅱ) salts were used as metal sources and N,N-dimethylformamide was employed as a solvent as well as a reductant to produce Cu(Ⅰ) complexes.(ⅱ) An iodide-containing compound was utilized as a ligand and iodide source to prepare complexes.An in situ metalligand reaction occurred and an iodide-bridged copper complex was generated.(ⅲ) A series of aldehydes were added to the reaction systems to induce in situ metal-ligand reactions between the aldehydes and the imidazo[1,5-a]pyridine derivatives,producing polydentate ligand scaffolds.Eight complexes were prepared and characterized.The catalytic activities of these complexes toward the ketalization of ketones by ethylene glycol were investigated.With the exception of complex4,the remaining seven complexes all showed high catalytic activity.The lower activity of 4 may be due to the larger radius of bridging iodide ions and the shorter Cu(Ⅰ)…Cu(Ⅰ) distance.CCDC:2357696,1·2CH_(2)Cl_(2);2357697,2;2018292,3;2092192,4;2092190,5;2155557,6;2406155,7;2406156,8·EtOH. 展开更多
关键词 copper complexes imidazo[1 5‑a]pyridine in situ metal-ligand reactions ketalization reactions
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Influence of Current Density and Copper Ion Concentration on Properties of Electrodeposited Cu-Ni Coatings
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作者 Guo Xuyan Xiong Zhuangzhuang +5 位作者 Wang Guixiang Zhou Qiang Wu Yanxiong Kong Delong Ma Fuqiu Wu Ruizhi 《稀有金属材料与工程》 北大核心 2025年第9期2231-2240,共10页
A straightforward,highly effective,and environmentally friendly technique was investigated for protecting carbon steel surfaces from corrosion,i.e.,depositing Cu-Ni alloy coatings on the workpiece’s surface to impede... A straightforward,highly effective,and environmentally friendly technique was investigated for protecting carbon steel surfaces from corrosion,i.e.,depositing Cu-Ni alloy coatings on the workpiece’s surface to impede corrosive medium.The effects of current density and copper ion concentration(Cu^(2+))on the composition,morphology,and properties of the coating were analyzed using scanning electron microscope,X-ray energy dispersive spectrometer,Vickers hardness tester,friction and wear tester,and electrochemical testing.Results show that a cauliflower-like Ni-rich protrusion structure appears on the coating surface.The lower current density and Cu^(2+)concentration affect the Vickers hardness and wear resistance of the coating by altering the microstructure and Cu/Ni content,both leading to a decrease in hardness and wear resistance.When the current density is 10 mA·cm^(-2)and the Cu^(2+)concentration is 0.1 mol·L^(−1),the corrosion current density of the deposited sample reaches 1.389×10^(−5)A·cm^(-2),and its surface corrosion damage is reduced compared to the uncoated sample after 24 h of salt spray test.Research on the deposition mechanism indicates that Cu^(2+)undergoes instantaneous nucleation under diffusion control,tending to grow vertically and form cauliflower-like protrusions,while Ni^(2+)is discharged uniformly across the surface under electrochemical control. 展开更多
关键词 Cu-Ni coatings corrosion protection MORPHOLOGY PERFORMANCE
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Distinct association of HRAS and KRAS with Mn^(2+) ion illustrated by paramagnetic NMR
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作者 Jia-Liang Chen Xun-Cheng Su 《Magnetic Resonance Letters》 2025年第1期22-31,共10页
Rat sarcoma virus oncogene(RAS)proteins are of crucial oncogenic proteins and are involved in several essential intracellular processes.The RAS protein has an intrinsic metal binding site for Mg^(2+),which is importan... Rat sarcoma virus oncogene(RAS)proteins are of crucial oncogenic proteins and are involved in several essential intracellular processes.The RAS protein has an intrinsic metal binding site for Mg^(2+),which is important for the conformational stability of the active site.Recently,it was reported that a second metal ion binding site,located further from the active site in HRAS(Harvey RAS homolog),binds Ca^(2+) with millimolar affinity.As one of the most abundant metal ions in cells,Mn^(2+) is a potential candidate for the second metal ion binding site in RAS proteins.Here,we examined the interaction of Mn^(2+) with HRAS and KRAS(Kirsten RAS homolog)using high resolution NMR spectroscopy.The NMR data showed that both the second metal ion binding site and the switch I and II regions bind Mn^(2+) in the RAS proteins.Furthermore,our paramagnetic NMR results disclosed the conformational differences in helix a3 and the following loop between HRAS and KRAS,accompanied by the association with metal ion binding.These results provide new insights into the interaction of RAS proteins and Mn^(2+) in the respective biological processes in cells. 展开更多
关键词 HRAS KRAS Mn^(2+) NMR PRE
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Polyvinyl alcohol fiber with enhanced strength and modulus and intense cyan fluorescence based on covalently functionalized graphene quantum dots
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作者 Manman Ou Yunjian Zhu +5 位作者 Jiahao Liu Zhaoxuan Liu Jianjun Wang Jun Sun Chuanxiang Qin Lixing Dai 《Chinese Chemical Letters》 2025年第2期222-227,共6页
In this study,we proposed a novel and efficient way to strengthen polyvinyl alcohol(PVA)fiber using graphene quantum dots(GQDs).PVA molecular chains were grafted onto the surface of GQDs through Friedel-Crafts alkylat... In this study,we proposed a novel and efficient way to strengthen polyvinyl alcohol(PVA)fiber using graphene quantum dots(GQDs).PVA molecular chains were grafted onto the surface of GQDs through Friedel-Crafts alkylation reaction to obtain functionalized GQDs(f-GQDs),and PVA/f-GQDs composite fiber was successfully prepared by wet spinning and post-treatment.The tensile strength and Young's modulus of the composite fiber reached up to 1229.24 MPa and 35.36 GPa which were approximately twice and 4 times those of the pure PVA fiber,respectively.Moreover,the composite fiber was demonstrated excellent resistance to solvents.In addition,the PVA/f-GQDs composite fiber showed intense and uniform cyan fluorescence,meanwhile,it could maintain stable solid-state fluorescence in acid and alkali solutions and particularly after long-term immersion in water(1 month).This study proposes a promising route for obtaining high-performance conventional fibers with some new functions. 展开更多
关键词 Polyvinyl alcohol fiber Graphene quantum dots Enhancement FLUORESCENCE
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Polymerizable Deep Eutectic Solvent-derived Ionic Conductive Elastomers for Strain and Temperature Sensing
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作者 Chen-Lin Pan Zheng-Yang Qian +2 位作者 Hao Chen Jin-Lin He Pei-Hong Ni 《Chinese Journal of Polymer Science》 2025年第12期2373-2385,I0014,共14页
In recent years,flexible ionic conductors have made remarkable progress in the fields of energy storage devices and flexible sensors.However,most of these materials still face challenges such as the difficult trade-of... In recent years,flexible ionic conductors have made remarkable progress in the fields of energy storage devices and flexible sensors.However,most of these materials still face challenges such as the difficult trade-off between stretchability and high mechanical strength,as well as insufficient ionic conductivity.Among them,polymerizable deep eutectic solvents(PDES),which possess both hydrogen bond network construction capabilities and ionic conduction properties,have demonstrated great advantages in the synthesis of flexible ionic conductors.Herein,we report an ionic conductive elastomer(ICE)named PCHS-X based on PDES composed of 2-(methacryloyloxy)-N,N,N-trimethylammonium methyl sulfate(MA-MS),choline chloride(ChCl),and 2-hydroxyethyl acrylate(HEA).The introduction of MA-MS enabled the polymer network to form abundant hydrogen bonds,endowing PCHS-X with excellent mechanical strength,high transparency,favorable ionic conductivity,self-adhesiveness,and self-healing efficiency.When used as a strain sensor,the PCHS-X exhibits highly sensitive strain response,along with good stability and durability,allowing it to accurately monitor the movement of human body parts such as fingers,wrists,elbows,and knees.Additionally,owing to the enhanced ionic mobility at higher temperatures,this material also possesses excellent temperature sensing performance,enabling the fabrication of simple temperature sensors that can sensitively respond to temperature changes.This research provides new strategies for the practical applications of flexible electronic devices in fields such as wearable health monitoring and intelligent human-machine interaction. 展开更多
关键词 Polymerizable deep eutectic solvents Ionic conductive elastomer Flexible electronic Strain sensing Temperature sensing
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