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Chloromycetin resistance of clinically isolated E coli is conversed by using EGS technique to repress the Chloromycetin acetyl transferase 被引量:3
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作者 Mei-Ying Gao Chuan-Rui Xu +2 位作者 RU Chen Shou-Gui Liu Jiang-Nan Feng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第46期7368-7373,共6页
AIM: To explore the possibility of repression of chloromycetin (Cm) acyl transferase by using external guided sequence (EGS) in order to converse the clinical E coli isolates from Cm- resistant to Cm- sensitive. ... AIM: To explore the possibility of repression of chloromycetin (Cm) acyl transferase by using external guided sequence (EGS) in order to converse the clinical E coli isolates from Cm- resistant to Cm- sensitive. METHODS: EGS directed against chloromycetin acetyl transferase gene (cat) was cloned to vector pEGFP-C1 which contains the kanamycin (Kin) resistance gene. The recombinant plasmid pEGFP-C1+EGScatl+cat2 was constructed and the blank vector without EGS fragment was used as control plasmids. By using the CaCl2 transformation method, the recombinant plasmids were introduced into the clinically isolated Cm resistant but Km sensitive E coli strains. Transformants were screened on LB agar plates containing Kin. Extraction of plasmids and PCR were applied to identify the positive clones. The growth curve of EGS transformed bacteria cultured in broth with Cm resistance was determined by using spectrophotometer at A600. Drug sensitivity was tested in solid culture containing Cm by using KB method. RESULTS: Transformation studies were carried out on 16 clinically isolated Cm-resistant (250 μg/mL of Cm) E colistrains by using pEGFP-C1-EGScatlcat2 recombinant plasmid. Transformants were screened on LB-agar plates containing Km after the transformation using EGS. Of the 16 tested strains, 4 strains were transformed successfully. Transformants with EGS plasmid showed growth inhibition when grown in liquid broth culture containing 200 μg/mL of Cm. In drug sensitivity test, these strains were sensitive to Cm on LB-agar plates containing 200 μg/mL of Cm. Extraction of plasmids and PCR amplification showed the existence of EGS plasmids in these four transformed strains. These results indicated that the Cat of the four clinical isolates had been suppressed and the four strains were converted to Cm sensitive ones. CONCLUSION: The EGS directed against Cat is able to inhibit the expression of Cat, and hence convert Cm- resistant bacteria to Cm-sensitive ones. Thus, the EGS has the capability of converting the phenotype of clinical drug-resistant isolates strains to drug-sensitive ones. 展开更多
关键词 External guide sequence Drug-resistant bacteria Conversion of drug resistance
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The Application of Lights-Conversed Polyethylene Film for Agriculture
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作者 Zhang Ke\|li, Yuan Liang\|jie, Xi Mei\|yun, Yu You\|zu, Sun Ju\|tang College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, Hubei, China 《Wuhan University Journal of Natural Sciences》 CAS 2002年第3期365-367,共3页
Lanthanum-rhodamine (6G and B) complexes were synthesized by Rheological Phase Reaction Method. Lanthanum-rhodamine (6G and B) complexes doped polyethylene films which have a function of lights-conversion were prepare... Lanthanum-rhodamine (6G and B) complexes were synthesized by Rheological Phase Reaction Method. Lanthanum-rhodamine (6G and B) complexes doped polyethylene films which have a function of lights-conversion were prepared. The emission and excitation spectra were measured. The experiments of growing seedling and culture were carried out in the shed built with doped and undoped polyethylene films. Lanthanum-rhodamine doped polyethylene films which have a function of lights-conversion can efficiently convert the green light in the sunlight to the red light for photosynthesis of crops, to promote the maturing of crops and raise the yield of crops. 展开更多
关键词 LANTHANUM lights CONVERSION polyethylene film RHODAMINE rheological phase reaction
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A review of nanodiamond-based photocatalysts for solar energy conversion
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作者 Zhang Wan Cheng Xiangxiang +5 位作者 Guo Kesheng Zhang Hansong Li Lanxiao Zhao Yongbing Zhu Jiaqi Wang Yongjie 《新型炭材料(中英文)》 北大核心 2026年第1期18-43,共26页
Photocatalysis is an important technology for using solar energy to produce hydrogen,convert CO_(2) to synthetic fuels,and decrease persistent pollutant.However,conventional photocatalysts have limitations,including p... Photocatalysis is an important technology for using solar energy to produce hydrogen,convert CO_(2) to synthetic fuels,and decrease persistent pollutant.However,conventional photocatalysts have limitations,including poor spectral absorption,inefficient charge separation,and structural instability under operational stress,which demand innovative durable materials with tailored electronic properties.Nanodiamond(ND)has recently been recognized as a suitable material because of its exceptional chemical stability,superior charge carrier mobility,and possible surface functionalization.While its intrinsic wide bandgap limits its response to visible-light,different methods have been demonstrated to activate its catalytic potential.Here,several emerging strategies for improving the catalytic performance of ND-based photocatalytic systems are summarized,including surface functionalization,plasmonic hybridization,heteroatom doping,and heterostructure design.And the structure-activity relationship and design principle are proposed to improve the light harvesting,charge transport,and redox kinetics for constructing high efficiency ND-based photocatalysts used in the renewable energy and environmental industries. 展开更多
关键词 PHOTOCATALYSIS NANODIAMOND Solar fuel conversions FUNCTIONALIZATION DOPING HETEROSTRUCTURE
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Facile synthesis of Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)solid solutions for improving photocatalytic CO_(2)reduction
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作者 WANG Jingzhou YAO Chenzhong +2 位作者 ZHANG Xisheng MA Ziwei LI Linfeng 《燃料化学学报(中英文)》 北大核心 2026年第1期15-25,共11页
In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar perce... In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar percentage of Na_(2)Ni_(2)Ti_(6)O_(16)(NNTO)within Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)(NMTO),with x values of 10,20,30,40,and 50.Both XPS(X-ray Photoelectron Spectroscopy)and EDX(Energy Dispersive X-ray Spectroscopy)analyses unequivocally validated the formation of the NNMTO-x solid solutions.It was observed that when x is below 40,the NNMTO-x solid solution retains the structural characteristics of the original NMTO.However,beyond this threshold,significant alterations in crystal morphology were noted,accompanied by a noticeable decline in photocatalytic activity.Notably,the absorption edge of NNMTO-x(x<40)exhibited a shift towards the visible-light spectrum,thereby substantially broadening the absorption range.The findings highlight that NNMTO-30 possesses the most pronounced photocatalytic activity for the reduction of CO_(2).Specifically,after a 6 h irradiation period,the production rates of CO and CH_(4)were recorded at 42.38 and 1.47μmol/g,respectively.This investigation provides pivotal insights that are instrumental in the advancement of highly efficient and stable photocatalysts tailored for CO_(2)reduction processes. 展开更多
关键词 photocatalytic conversion hydrothermal method optical response range solid solution charge separation
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Advances in electrocatalytic and photocatalytic CO_(2)conversion to value-added chemicals using copper-based covalent organic frameworks
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作者 LI Yue LIU Ziqi +7 位作者 FENG Ke LI Yingdan NING Yue SHEN Li LU Jitao MENG Qingguo WANG Min WANG Haiying 《无机化学学报》 北大核心 2026年第1期1-22,共22页
CO_(2)reduction technology can promote the resource utilization of carbon and help alleviate global warming and energy supply pressure.It is an effective way to achieve energy conversion and utilization.Covalent organ... CO_(2)reduction technology can promote the resource utilization of carbon and help alleviate global warming and energy supply pressure.It is an effective way to achieve energy conversion and utilization.Covalent organic frameworks(COFs)are porous crystalline materials formed by connecting organic monomers through covalent bonds.They have the characteristics of functional diversity and rich chemical properties.Their advantages,such as high porosity,a wide range of visible light absorption,and excellent charge separation efficiency,give them good potential in CO_(2)capture,separation,and conversion.Currently,Cu is a key metal in the catalytic CO_(2)reduction reaction(CO_(2)RR)for the preparation of high-value-added chemicals.The preparation of highly stable and large-pore Cu-based COFs using COFs as an ideal sacrificial template for loading Cu can be used to develop high-performance electrocatalysts and photocatalysts.In this review,we discuss the latest advancements in this field,including the development of various Cu-based COFs and their applications as catalysts for CO_(2)RR.Here,we mainly introduce the synthesis strategies,some important characterization information,and the applications of electrocatalytic and photocatalytic CO_(2)conversion using these previously reported Cu-based COFs. 展开更多
关键词 copper-based covalent organic frameworks CO_(2)reduction reactions electrocatalytic CO_(2)conversion photocatalytic CO_(2)conversion
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Three-dimensional Patterning Super-Black Silica-Based Nanocomposite Aerogels
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作者 Zhiyang Zhao Romain Civioc +13 位作者 Wei Liu Peiying Hu Mengmeng Li Fuhao Xu Robin Pauer Jiabei Luo Samuel Brunner PawełP.Ziemiański Ilia Sadykov Sandra Galmarini Yong Kong Xiaodong Shen Wim J.Malfait Shanyu Zhao 《Nano-Micro Letters》 2026年第2期1-18,共18页
Aerogels are ultra-lightweight,porous materials defined by a complex network of interconnected pores and nanostructures,which effectively suppress heat transfer,making them exceptional for thermal insulation.Furthermo... Aerogels are ultra-lightweight,porous materials defined by a complex network of interconnected pores and nanostructures,which effectively suppress heat transfer,making them exceptional for thermal insulation.Furthermore,their porous architecture can trap and scatter light via multiple internal reflections,extending the optical path within the material.When combined with suitable light-absorbing materials,this feature significantly enhances light absorption(darkness).To validate this concept,mesoporous silica aerogel particles were incorporated into a resorcinol-formaldehyde(RF)sol,and the silica-to-RF ratio was optimized to achieve uniform carbon compound coatings on the silica pore walls.Notably,increasing silica loading raised the sol viscosity,enabling formulations ideal for direct ink writing processes with excellent shape fidelity for super-black topographical designs.The printed silica-RF green bodies exhibited remarkable mechanical strength and ultra-low thermal conductivity(15.8 m W m^(-1) K^(-1))prior to pyrolysis.Following pyrolysis,the composites maintained structural integrity and printed microcellular geometries while achieving super-black coloration(abs.99.56%in the 280-2500 nm range)and high photothermal conversion efficiency(94.2%).Additionally,these silica-carbon aerogel microcellulars demonstrated stable electrical conductivity and low electrochemical impedance.The synergistic combination of 3D printability and super-black photothermal features makes these composites highly versatile for multifunctional applications,including on-demand thermal management,and efficient solar-driven water production. 展开更多
关键词 Super-black NANOCOMPOSITES AEROGEL 3D printing Photothermal conversion
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Hydrothermal conversion from hydrogarnet to hydroandradite based on alumina recovery from red mud
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作者 Hong-fei WU Xiao-lin PAN +3 位作者 Ji-long LIU Feng QIU Tun HE Hai-yan YU 《Transactions of Nonferrous Metals Society of China》 2026年第1期309-322,共14页
To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM ... To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM methods,and a novel hydrothermal process based on the conversion principle was finally proposed.The crystal structure simulation shows that the HA with varied silicon saturation coefficients is more stable than HG,and the HA with a high iron substitution coefficient is more difficult to be converted from HG.The(110)plane of Fe_(2)O_(3) is easier to combine with HG to form HA,and the binding energy is 81.93 kJ/mol.The effects of raw material ratio,solution concentration and hydrothermal parameters on the conversion from HG to HA were revealed,and the optimal conditions for the alumina recovery were obtained.The recovery efficiencies of alumina and Na_(2)O from the RM are 63.06%and 97.34%,respectively,and the Na_(2)O content in the treated RM is only 0.13%. 展开更多
关键词 HYDROGARNET hydroandradite structural stability hydrothermal conversion red mud
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Impact of Shockwave on Condensation Efficiency of Supersonic Nozzle during Natural Gas Purification
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作者 Lei Zhao Lihui Ma +3 位作者 Junwen Chen Pan Zhang Jiang Bian Dong Sun 《Energy Engineering》 2026年第2期314-328,共15页
Shock waves in the nozzle during supersonic separation under different conditions can disrupt the flow field’s thermodynamic equilibrium.While it contributes to the recovery of pressure energy,it also leads to the di... Shock waves in the nozzle during supersonic separation under different conditions can disrupt the flow field’s thermodynamic equilibrium.While it contributes to the recovery of pressure energy,it also leads to the dissipation of mechanical energy.This study aimed to investigate the effects of changes in back pressure on the shock wave position and its subsequent impact on the refrigeration performance of nozzles.A mathematical model for the supersonic gas in a nozzle was established and evaluated via experiments.The results show that when the back pressure is less than 0.2 MPa,no shock wave is generated in the nozzle,and high refrigeration and liquefaction efficiency can be ensured while effective pressure recovery is achieved.When the back pressure(pb)is increased from 0.3 to 0.6 MPa,the refrigeration efficiency of the nozzle decreases,and the shock wave position(x shock)is advanced from 157 to 118 mm.The maximum Mach number(Ma)that can be reached by the fluid in the nozzle is reduced from 1.97 to 1.27.When the back pressure is increased from 0.2 to 0.6 MPa,the minimum temperature is increased by 55.18 K.When the back pressure is greater than 0.3 MPa,the Mach number upstream of the shock wave is reduced from 1.97 to 1.27,the shock wave intensity is weakened,and the thickness of the boundary layer separation caused by the shock wave is also decreased accordingly.Therefore,to ensure refrigeration efficiency,measures should be taken to control the back pressure within a reasonable range. 展开更多
关键词 Supersonic nozzle SHOCKWAVE boundary layer energy conversion refrigeration efficiency
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Functionalized Wood:A Green Nanoengineering Platform for Sustainable Technologies
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作者 Tuo Zhang Mingwei Gu +8 位作者 Yizhu Liu Guangyao Chen Haiyang Zhang Liguo Chen Xingwen Zhou Lining Sun Zhen Wen Yunlei Zhou Haibo Huang 《Nano-Micro Letters》 2026年第4期54-113,共60页
Wood,once regarded primarily as a structural material,possesses rich physicochemical complexity that has long been underexplored.In the context of industrialization and carbon imbalance,it is now emerging as a renewab... Wood,once regarded primarily as a structural material,possesses rich physicochemical complexity that has long been underexplored.In the context of industrialization and carbon imbalance,it is now emerging as a renewable and multifunctional platform for green nanotechnologies.Recent advances in wood nanotechnology have enabled the transformation of natural wood into programmable substrates with tailored nanoarchitectures,establishing it as a representative class of bio-based nanomaterials.This review systematically categorizes wood-specific nanoengineering strategies—including thermal carbonization,laser-induced graphenization,targeted delignification,nanomaterial integration,and mechanical processing—highlighting their mechanisms and impacts on wood's multiscale structural and functional properties.Importantly,these functionalization strategies can be flexibly combined in a modular,“Lego-like”manner,enabling wood to be reconfigured and optimized for diverse application scenarios.We summarize recent progress in applying functionalized wood to sustainable technologies such as energy storage(e.g.,metal-ion batteries,Zn-air systems,supercapacitors),water treatment(e.g.,adsorption,photothermal filtration,catalytic degradation),and energy conversion(e.g.,solar evaporation,ionic thermoelectrics,hydrovoltaics,and triboelectric nanogenerators).These studies reveal how nanoengineered wood structures can enable efficient charge transport,selective adsorption,and enhanced light-to-heat conversion.Finally,the review discusses current challenges—such as scalable fabrication,material integration,and long-term environmental stability—and outlines future directions for the development of wood-based platforms in next-generation green energy and environmental systems. 展开更多
关键词 Functionalized wood Bio-based nanomaterials Energy storage Water purification Energy conversion
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A Synchronous Strategy to Zn-Iodine Battery by Polycationic Long-Chain Molecules
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作者 Da-Qian Cai Hengyue Xu +2 位作者 Tong Xue Jin-Lin Yang Hong Jin Fan 《Nano-Micro Letters》 2026年第1期80-94,共15页
Aqueous Zn-iodine batteries(ZIBs)face the formidable challenges towards practical implementation,including metal corrosion and rampant dendrite growth on the Zn anode side,and shuttle effect of polyiodide species from... Aqueous Zn-iodine batteries(ZIBs)face the formidable challenges towards practical implementation,including metal corrosion and rampant dendrite growth on the Zn anode side,and shuttle effect of polyiodide species from the cathode side.These challenges lead to poor cycle stability and severe self-discharge.From the fabrication and cost point of view,it is technologically more viable to deploy electrolyte engineering than electrode protection strategies.More importantly,a synchronous method for modulation of both cathode and anode is pivotal,which has been often neglected in prior studies.In this work,cationic poly(allylamine hydrochloride)(Pah^(+))is adopted as a low-cost dual-function electrolyte additive for ZIBs.We elaborate the synchronous effect by Pah^(+)in stabilizing Zn anode and immobilizing polyiodide anions.The fabricated Zn-iodine coin cell with Pah^(+)(ZnI_(2) loading:25 mg cm^(−2))stably cycles 1000 times at 1 C,and a single-layered 3.4 cm^(2) pouch cell(N/P ratio~1.5)with the same mass loading cycles over 300 times with insignificant capacity decay. 展开更多
关键词 Polyiodide shuttle effect Halogen battery Conversion cathode DENDRITES Polycation molecule
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Solar-Driven Redox Reactions with Metal Halide Perovskites Heterogeneous Structures
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作者 Qing Guo Jin‑Dan Zhang +1 位作者 Jian Li Xiyuan Feng 《Nano-Micro Letters》 2026年第2期337-367,共31页
Metal halide perovskites(MHPs)with striking electrical and optical properties have appeared at the forefront of semiconductor materials for photocatalytic redox reactions but still suffer from some intrinsic drawbacks... Metal halide perovskites(MHPs)with striking electrical and optical properties have appeared at the forefront of semiconductor materials for photocatalytic redox reactions but still suffer from some intrinsic drawbacks such as inferior stability,severe charge-carrier recombination,and limited active sites.Heterojunctions have recently been widely constructed to improve light absorption,passivate surface for enhanced stability,and promote charge-carrier dynamics of MHPs.However,little attention has been paid to the review of MHPs-based heterojunctions for photocatalytic redox reactions.Here,recent advances of MHPs-based heterojunctions for photocatalytic redox reactions are highlighted.The structure,synthesis,and photophysical properties of MHPs-based heterojunctions are first introduced,including basic principles,categories(such as Schottky junction,type-I,type-II,Z-scheme,and S-scheme junction),and synthesis strategies.MHPs-based heterojunctions for photocatalytic redox reactions are then reviewed in four categories:H2evolution,CO_(2)reduction,pollutant degradation,and organic synthesis.The challenges and prospects in solar-light-driven redox reactions with MHPs-based heterojunctions in the future are finally discussed. 展开更多
关键词 Metal halide perovskite HETEROJUNCTION Redox reaction Solar-to-chemical conversion
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Long-lived metal-zeolite catalysts for polyolefin aromatization via synergistic tandem dehydroaromatization and hydrogenolysis
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作者 Wenjun Chen Yiyi Fan +2 位作者 Yue Liu Xiaobin Xie Fan Zhang 《Journal of Energy Chemistry》 2026年第1期465-473,I0011,共10页
Converting waste plastics directly into valuable aromatic chemicals is a promising,cost-effective recycling strategy.Traditional zeolite-catalyzed cracking of polyolefins to produce aromatics often needs high temperat... Converting waste plastics directly into valuable aromatic chemicals is a promising,cost-effective recycling strategy.Traditional zeolite-catalyzed cracking of polyolefins to produce aromatics often needs high temperatures and faces issues like low selectivity for liquid aromatics,separation difficulties,and rapid catalyst deactivation due to coking.To address this,a multifunctional Ni/HZSM-5 catalyst was developed to efficiently upgrade various polyolefins—including polyvinyl chloride—into gaseous alkanes(C_(1)–C_(5))and easily separable liquid aromatics(C_(6)–C_(12))at 400°C,without added solvents or hydrogen.Aromatic products make up 57.1 wt%of total output,with more than 97.8%selectivity for the liquid phase and a BTX(benzene,toluene,and xylene)selectivity of 76.1%.The high activity and selectivity for aromatics stem from synergistic interactions between Ni nanoparticles(NPs)and acid sites in the zeolite,which promote selective C–C bond breaking and control hydrogenolysis and aromatization pathways.This synergy allows precise control over the distribution of products by carbon number and favors the formation of separable aromatics.Notably,the catalyst also prevents coking by hydrogenolyzing and hydrogenating reactive intermediates before they form stable graphite-like deposits.Consequently,Ni/ZSM-5 catalyst demonstrates excellent stability,maintaining consistent aromatics yield over 13 consecutive cycles and processing over 30 times its weight in plastics without regeneration.After regeneration,the activity of the catalyst was fully restored,highlighting its potential for industrial use.This work offers valuable insights for designing durable,high-activity catalysts,providing a practical route to improve plastic recycling technologies. 展开更多
关键词 POLYOLEFIN Catalytic conversion Ni/ZSM-5 AROMATICS Tandem reaction
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Bio-inspired amino acid promoted nanofluidic ion transport and energy conversion in free-standing layered vermiculite-based membranes
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作者 Ruohan Feng Chaoran Zhang +1 位作者 Di Zhang Fang Song 《Green Energy & Environment》 2026年第1期248-257,共10页
Two-dimensional nanofluidic membranes have garnered considerable interest due to their potential for cost-effective osmotic energy harvesting.One promising approach to enhancing ion conductivity and selectivity is the... Two-dimensional nanofluidic membranes have garnered considerable interest due to their potential for cost-effective osmotic energy harvesting.One promising approach to enhancing ion conductivity and selectivity is the incorporation of vip additives.However,the traditional host-vip configuration can undermine the structural integrity of nanochannels owing to the inconsistent size and shape of these additives.Drawing inspiration from the intricate design of biological protein channels,which utilize small amino acid molecules as vips,we have addressed this issue by incorporating glycine,a common amino acid,into a vermiculite membrane using a simple vacuum-assisted infiltration method.The resulting vermiculite-glycine membrane demonstrates 1.8 times greater ionic conductivity and twice the power density compared to pure vermiculite membranes.Analysis based on glycine content,coupled with spectroscopic examination,reveals that ion conductivity is linked to the distribution of glycine molecules across three specific sites within the membrane.This suggests that glycine molecules—whether confined in voids,adsorbed onto nanochannel surfaces,or intercalated within multilayered vermiculite nanoparticles—enhance nanofluidic ion transport by modulating surface and space charge density,as well as strengthening hydrogen bonding,electrostatic interactions,and steric effects.This work reveals the specific interactions between amino acids and vermiculite,offering a novel path for advancing nanofluidic composite membranes and highlighting critical considerations for the proposed strategy. 展开更多
关键词 Amino acid Nanofluidics Ion transport Osmotic energy conversion Vermiculite-based membrane
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Single-atom catalysts for CO_(2)-to-methanol conversion:A critical review
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作者 Jingying Wang Jianhui Zhao +2 位作者 Shaopo Wang Jingjie Yu Ning Li 《Chinese Chemical Letters》 2026年第2期274-283,共10页
Catalytic CO_(2)-to-methanol conversion presents a synergistic approach for concurrent greenhouse gas abatement and sustainable energy carrier synthesis.Single-atom catalysts(SACs)with maximized atomic utilization,tai... Catalytic CO_(2)-to-methanol conversion presents a synergistic approach for concurrent greenhouse gas abatement and sustainable energy carrier synthesis.Single-atom catalysts(SACs)with maximized atomic utilization,tailored electronic configurations and unique metal-support interactions,exhibit superior performance in CO_(2) activation and methanol synthesis.This review systematically compares reaction mechanisms and pathways across thermal,photocatalytic and electrocatalytic systems,emphasizing structure-activity relationships governed by active sites,coordination microenvironments and support functionalities.Through case studies of representative SACs,we elucidate how metal-support synergies dictate intermediate binding energetics and methanol selectivity.A critical analysis of reaction parameters(e.g.,temperature,pressure)reveals condition-dependent catalytic behaviors in thermal system,with fewer studies in photo/electrocatalytic systems identified as key knowledge gaps.While thermal catalysis achieves industrially viable methanol yields,the scalability is constrained by energy-intensive operation and catalyst sintering.Conversely,photo/electrocatalytic routes offer renewable energy integration but suffer from inefficient charge dynamics and mass transport limitations.To address the challenges,we propose strategic research priorities on precise design of active sites,synergy of multiple technological pathways,development of intelligent catalytic systems and diverse CO_(2) feedstock compatibility.These insights establish a framework for developing next-generation SACs,offering both theoretical foundations and technological blueprints for developing carbon-negative catalytic technologies. 展开更多
关键词 Single-atom catalysts CO_(2)conversion METHANOL CATALYSIS
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Design and experimental validation of a low-impact wing locking/release mechanism based on energy conversion strategy
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作者 Yanbing Wang Honghao Yue +5 位作者 Jun Wu Xueting Pan Fei Yang Yong Zhao Jicheng Liu Xue Bai 《Defence Technology(防务技术)》 2026年第1期241-256,共16页
Conventional locking/release mechanisms often face challenges in aircraft wing separation processes,such as excessive impact loads and insufficient synchronization.These may cause structural damage to the airframe or ... Conventional locking/release mechanisms often face challenges in aircraft wing separation processes,such as excessive impact loads and insufficient synchronization.These may cause structural damage to the airframe or attitude instability,seriously compromising mission reliability.To address this engineering challenge,this paper proposes a multi-point low-impact locking/release mechanism based on the mobility model and energy conversion strategy.Through establishing a DOF constraint framework system,this paper systematically analyzes the energy transfer and conversion characteristics during the wing separation process,reveals the generation mechanism of impact loads,and conducts research on low-impact design based on energy conversion strategy.Building on this foundation,a single-point locking/release mechanism employing parallel trapezoidal key shaft structure was designed,which increases frictional contact time and reduces the energy release rate,thereby achieving low-impact characteristics.The mechanism's performance was validated through physical prototype development and systematic functional testing(including unlocking force,synchronization,and impact tests).Experimental results demonstrate:(1)Under 14 kN preload condition,the maximum unlocking force was only 92.54 N,showing a linear relationship with preload that satisfies the"strong-connection/weak-unlock"design requirement;(2)Wing separation was completed within 46 ms,with synchronization time difference among three separation mechanisms stably controlled within 12-14 ms,proving rapid and reliable operation;(3)The unlocking impact acceleration ranged between 26 and 73 g,below the 100 g design limit,confirming the effectiveness of the energy conversion strategy.The proposed low-impact locking/release mechanism design method based on energy conversion strategy resolves the traditional challenges of high impact and synchronization deficiencies.The synergistic optimization mechanism of"structural load reduction and performance improvement"provides a highly reliable technical solution for wing separable mechanisms while offering novel design insights for wing connection/separation systems engineering. 展开更多
关键词 Hypersonic vehicle Energy conversion strategy Low-impact Wing separation Locking/release mechanism
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Multiscale“pore-film”cross-linked photothermal hygroscopic sponge for solar-driven atmospheric water harvesting
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作者 Yan Li Minmin Li +1 位作者 Fan Dong Wen Cui 《Chinese Chemical Letters》 2026年第2期649-654,共6页
Freshwater scarcity is exacerbated by uneven distribution of limited freshwater resources and high energy costs of desalination technologies.Atmospheric water vapor,a vast and geographically unrestricted reservoir,cou... Freshwater scarcity is exacerbated by uneven distribution of limited freshwater resources and high energy costs of desalination technologies.Atmospheric water vapor,a vast and geographically unrestricted reservoir,could become a sustainable alternative.Sorption-based atmospheric water harvesting(SAWH)has emerged as an available solution,yet conventional desorption methods relying on energy-intensive electrical heating hinder its scalability.Herein,a photothermal hygroscopic sponge has been developed for solar-driven atmospheric water harvesting.The composites combine a malleable melamine sponge skeleton,lithium chloride as a hygroscopic agent,and hydrangea-like molybdenum disulfide as a photothermal component,forming a multiscale“pore-film”cross-linked structure by an eco-friendly immersion-freeze-drying method.The optimized sample achieves exceptional hygroscopic capacity(3.92 g/g at 90%RH)and freshwater production efficiency(87.77%),which is attributed to synergistic effects of porous skeleton based crosslinked structures and“pore-film”structures,and outstanding photothermal conversion efficiency of MoS2.The unique structure could stabilize LiCl to prevent leakage,increase mass transfer effectiveness of whole SWAH process,and enable flexibility for diverse applications.We carried out outdoor experiments to demonstrate a solar-driven water production rate of 4.22 L m-2 d-1 without external energy input.This work provides insights into sustainable freshwater generation and promotes green energy utilization in addressing global water scarcity. 展开更多
关键词 Sorption-based atmospheric water HARVESTING Pore-film structure Hygroscopic sponge Photothermal conversion Mass and heat transfer
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Mechanical Analysis of Free-Standing Cold-Water Pipe for Ocean Thermal Energy Conversion
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作者 Jing Li Bo Ning +3 位作者 Bo Li Xuemei Jin Dezhi Qiu Fenlan Ou 《Fluid Dynamics & Materials Processing》 2026年第1期86-100,共15页
As a controllable power generation method requiring no energy storage,Ocean Thermal Energy Conversion(OTEC)technology demonstrates characteristics of abundant reserves,low pollution,and round-the-clock stable operatio... As a controllable power generation method requiring no energy storage,Ocean Thermal Energy Conversion(OTEC)technology demonstrates characteristics of abundant reserves,low pollution,and round-the-clock stable operation.The free-standing cold-water pipe(CWP)in the system withstands various complex loads during operation,posing potential failure risks.To reveal the deformation and stress mechanisms of OTEC CWPs,this study first analyzes wave particle velocity and acceleration to determine wave loads at different water depths.Based on the Euler-Bernoulli beam model,a quasi-static load calculation model for OTEC CWPs was established.The governing equations were discretized using the finite difference method,and matrix equations were solved to analyze bending deformation,bending moments,and surface stresses at discrete points along the pipe.Results indicate that water depths within 50 m represent a critical zone where wave particle velocity,acceleration,and wave loads exhibit significant variations in harmonic patterns,while beyond 50 m depth wave loads decrease linearly.Ocean currents and surface wind-driven currents substantially influence the CWP’s lateral displacement.Considering the effect of clump weights,the maximum lateral displacement occurs at 600–800 m below sea level.Utilizing large-wall-thickness high-strength pipes at the top section significantly enhances the structural safety of the CWP system. 展开更多
关键词 Ocean thermal energy conversion wave load free standing pipe force analysis lateral displacement
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The influence of the interfacial microenvironment on the selectivity of target products
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作者 Zi-Han Chen Jin-Chao Dong Jian-Feng Li 《Science China Chemistry》 2026年第2期525-526,共2页
The production of valuable chemicals using copper(Cu)catalysts via electrochemical CO or CO_(2)reduction reactions(CORR and CO_(2)RR)has shown great potential in the field of sustainable energy conversion[1].Previous ... The production of valuable chemicals using copper(Cu)catalysts via electrochemical CO or CO_(2)reduction reactions(CORR and CO_(2)RR)has shown great potential in the field of sustainable energy conversion[1].Previous research has primarily focused on analyzing the behavior of reaction intermediates or solely on the dynamics within the solution phase,while the synergistic effects between surface species and the solution,particularly the interfacial water and its non-covalent interactions with the Cu surface,have remained partially understood[2]. 展开更多
关键词 sustainable energy conversion previous cu surfaceha interfacial microenvironment surface species synergistic effects electrochemical co production valuable chemicals reaction intermediates
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Effect of fluorination positions at diphenylamino flanking groups on the photovoltaic performance for nonfused ring electron acceptors
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作者 Yang Gao Huarui Zhang +7 位作者 Yan Xie Xinjun Xu Yahui Liu Hao Lu Wenkai Zhang Yuqiang Liu Cuihong Li Zhishan Bo 《Chinese Chemical Letters》 2026年第1期368-373,共6页
The fluorination strategy has been proven effective in significantly enhancing the photovoltaic performance of organic solar cells(OSCs) based on non-fused ring electron acceptors(NFREAs).However,research on the impac... The fluorination strategy has been proven effective in significantly enhancing the photovoltaic performance of organic solar cells(OSCs) based on non-fused ring electron acceptors(NFREAs).However,research on the impact of fluorination positions at side chains on NFREAs device performance remains scant.In this study,we introduce two isomeric NFREAs,designated as GA-2F-E and GA-2F,distinguished by their fluorination positions at the side chains.Both NFREAs share a thiophene[3,2-b]thiophene core,but their side chains differ:GA-2F-E features two(4-butylphenyl)-N-(4-fluorophenyl) amino groups,whereas GA-2F's side chains consist of bis(4-fluorophenyl)amino and bis(4-butylphenyl)amino groups attached to opposite sides of the core.To delve into the influence of fluorination positions on the optoelectronic properties,aggregation behavior,and overall efficiency of the acceptor molecules,a comprehensive investigation was conducted.The findings reveal that,despite similar photophysical properties and comparable absorption bandwidths,GA-2F-E,with fluorine atoms positioned on both sides of the molecular framework,demonstrates more compact π-π stacking,reduced bimolecular recombination,superior exciton transport,and a more balanced,higher mobility.As a result of these advantages,OSCs optimized with D18:GA-2F-E achieve a remarkable power conversion efficiency(PCE) of 16.45 %,surpassing the 15.83 %PCE of devices utilizing D18:GA-2F.This research underscores the potential of NFREAs in future applications and highlights the significance of fluorination positions in enhancing OSC performance,paving the way for the development of more efficient NFREAs. 展开更多
关键词 Organic solar cells Non-fused ring electron acceptors Fluorination position Diphenylamino groups Power conversion efficiencies
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Asymmetric Side‑Group Engineering of Nonfused Ring Electron Acceptors for High‑Efficiency Thick‑Film Organic Solar Cells
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作者 Dawei Li Nan Wei +11 位作者 Ya‑Nan Chen Xiaodong Wang Xu Han Ziqing Bian Xinyuan Zhang Zhe Zhang Wenkai Zhang Xinjun Xu Cuihong Li Yahui Liu Hao Lu Zhishan Bo 《Nano-Micro Letters》 2026年第3期227-239,共13页
A nonfused ring electron acceptor(NFREA),designated as TT-Ph-C6,has been synthesized with the aim of enhancing the power conversion efficiency(PCE)of organic solar cells(OSCs).By integrating asymmetric phenylalkylamin... A nonfused ring electron acceptor(NFREA),designated as TT-Ph-C6,has been synthesized with the aim of enhancing the power conversion efficiency(PCE)of organic solar cells(OSCs).By integrating asymmetric phenylalkylamino side groups,TT-Ph-C6 demonstrates excellent solubility and its crystal structure exhibits compact packing structures with a three-dimensional molecular stacking network.These structural attributes markedly promote exciton diffusion and charge carrier mobility,particularly advantageous for the fabrication of thick-film devices.TT-Ph-C6-based devices have attained a PCE of 18.01%at a film thickness of 100 nm,and even at a film thickness of 300 nm,the PCE remains at 14.64%,surpassing that of devices based on 2BTh-2F.These remarkable properties position TT-Ph-C6 as a highly promising NFREA material for boosting the efficiency of OSCs. 展开更多
关键词 Organic solar cells Nonfused ring electron acceptors ASYMMETRIC Power conversion efficiency
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