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Some discussions about method for solving the variable separating nonlinear models
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作者 阮航宇 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期17-24,共8页
Through analysing the exact solution of some nonlinear models, the role of the variable separating method in solving nonlinear equations is discussed. We find that rich solution structures of some special fields of th... Through analysing the exact solution of some nonlinear models, the role of the variable separating method in solving nonlinear equations is discussed. We find that rich solution structures of some special fields of these equations come from the nonzero seed solution. However, these nonzero seed solutions is likely to result in the divergent phenomena for the other field component of the same equation. The convergence and the signification of all field components should be discussed when someone solves the nonlinear equation using the variable separating method. 展开更多
关键词 variable separating method nonzero seed solution nonlinear equation
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Enhancing Piezoelectric Output via Constrained Phase Separation on Single Nanofibers:Harnessing Endogenous Triboelectricity 被引量:1
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作者 YU Dingming LIU Lifang +2 位作者 YU Jianyong SI Yang DING Bin 《Journal of Donghua University(English Edition)》 2025年第1期12-19,共8页
The research,fabrication and development of piezoelectric nanofibrous materials offer effective solutions to the challenges related to energy consumption and non-renewable resources.However,enhancing their electrical ... The research,fabrication and development of piezoelectric nanofibrous materials offer effective solutions to the challenges related to energy consumption and non-renewable resources.However,enhancing their electrical output still remains a significant challenge.Here,a strategy of inducing constrained phase separation on single nanofibers via shear force was proposed.Employing electrospinning technology,a polyacrylonitrile/polyvinylidene difluoride(PAN/PVDF)nanofibrous membrane was fabricated in one step,which enabled simultaneous piezoelectric and triboelectric conversion within a single-layer membrane.Each nanofiber contained independent components of PAN and PVDF and exhibited a rough surface.The abundant frictional contact points formed between these heterogeneous components contributed to an enhanced endogenous triboelectric output,showcasing an excellent synergistic effect of piezoelectric and triboelectric response in the nanofibrous membrane.Additionally,the component mass ratio influenced the microstructure,piezoelectric conformation and piezoelectric performance of the PAN/PVDF nanofibrous membranes.Through comprehensive performance comparison,the optimal mass ratio of PAN to PVDF was determined to be 9∶1.The piezoelectric devices made of the optimal PAN/PVDF nanofibrous membranes with rough nanofiber surfaces generated an output voltage of 20 V,which was about 1.8 times that of the smooth one at the same component mass ratio.The strategy of constrained phase separation on the surface of individual nanofibers provides a new approach to enhance the output performance of single-layer piezoelectric nanofibrous materials. 展开更多
关键词 nanofibrous membrane constrained phase separation endogenous triboelectric effect dual-component piezoelectric property
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Methods for separating the noise produced by the wheels and track during a train pass‑by
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作者 David Thompson Dong Zhao +4 位作者 Giacomo Squicciarini Martin Toward Ester Cierco Erwin Jansen Michael Dittrich 《Railway Engineering Science》 2025年第3期342-358,共17页
Rolling noise is produced by vibration of the wheels and track,induced by their combined surface roughness.It is important to know the relative contributions of the different sources,as this affects noise control stra... Rolling noise is produced by vibration of the wheels and track,induced by their combined surface roughness.It is important to know the relative contributions of the different sources,as this affects noise control strategies as well as acceptance testing of new rolling stock.Three different techniques are described that aim to use pass-by measurements to separate the wheel and track components of rolling noise.One is based on the TWINS model,which is tuned to measured track vibration.The second is based on the advanced transfer path analysis method,which provides an entirely experimental assessment.The third is based on the pass-by analysis method in combination with static vibroacoustic transfer functions which are obtained using a reciprocity method.The development of these methods is described and comparisons between them are presented using the results from three experimental measurement campaigns.These covered a metro train,a regional train and a high-speed train at a range of speeds.The various methods agree reasonably well in terms of overall trends,with moderate agreement in the mid-frequency region,and less consistent results at low and high frequency. 展开更多
关键词 Railway noise Rolling noise Source separation Pass-by tests
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A new method for separating complex touching equiaxed and lamellar alpha phases in microstructure of titanium alloy 被引量:1
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作者 吉喆 杨合 +1 位作者 李宏伟 樊晓光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第8期2265-2269,共5页
A new method for separating complex touching equiaxed and lamellar alpha phases in the optical micrograph of titanium alloy was proposed for quantitative characterization. This new method involves three steps. First, ... A new method for separating complex touching equiaxed and lamellar alpha phases in the optical micrograph of titanium alloy was proposed for quantitative characterization. This new method involves three steps. First, concave points of the microstructural feature are identified with a threshold of the concaveness of the comer points which are extracted from the binarized image. Secondly, concave points pairs are selected from the concave points group established by means of marker circle or distance. Third, whether a candidate separation line which connects two concave points within a pair can be accepted or not is determined by the proposed four rules. The obtained results show that this method is effective on separating complex touching microstructural features. 展开更多
关键词 titanium alloy microstructural feature separation method
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Spatial Layout Art of Chinese Private Gardens 被引量:1
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作者 赵亚敏 葛海霞 《Journal of Landscape Research》 2011年第1期15-17,20,共4页
Private garden is one of the three major garden styles in China,the artistic achievements of which have devoted remarkable contributions to the development of global landscape architecture.Through studying the spatial... Private garden is one of the three major garden styles in China,the artistic achievements of which have devoted remarkable contributions to the development of global landscape architecture.Through studying the spatial layout of private gardens,the authors further analyzed three ways of landscape layouts,specifically,separated scenery,winding scenery and borrowed scenery.Concrete examples were taken to demonstrate the connotations and application skills of such three layouts,in order to benefit the inheritance and development of traditional Chinese garden art. 展开更多
关键词 PRIVATE GARDEN Spatial layout SEPARATED SCENERY WINDING SCENERY Borrowed SCENERY
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A new combination process of distillation with salt extraction for separating organic solvent-water azeotropes
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作者 潘晓梅 肖国民 杨志才 《Journal of Southeast University(English Edition)》 EI CAS 2004年第2期226-228,共3页
A novel process which can purify the organic solvents from their azeotropes with water is proposed. In this process,water can be drained off both from bottom and overhead of tower at the same time,and the organic solv... A novel process which can purify the organic solvents from their azeotropes with water is proposed. In this process,water can be drained off both from bottom and overhead of tower at the same time,and the organic solvent is concentrated in the tower and accumulated in the middle vessel at last. So the progress is time-shortened and energy-saving. The product purity is 99. 8% and the product yield is more than 99.5%. Simulation of liquid-liquid equilibrium (LLE) and the equipment operation data agree well with the experiment. 展开更多
关键词 AZEOTROPE SEPARATION bath distillation salt extraction
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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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Bastnaesite carbochlorination process with fluorine fixation agents:An approach for low-waste rare earth extraction
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作者 Haiyue Xue Guozhi Lv +4 位作者 Long Wang Jiawei Ren Xinxin Zhao Song Wang Tingan Zhang 《Chinese Journal of Chemical Engineering》 2026年第1期47-58,共12页
As an important strategic rare-earth resource,bastnaesite has long been a global research focus.The carbochlorination process,as an efficient and low-cost extraction method,can be applied to treat bastnaesite,achievin... As an important strategic rare-earth resource,bastnaesite has long been a global research focus.The carbochlorination process,as an efficient and low-cost extraction method,can be applied to treat bastnaesite,achieving ideal rare-earth extraction results in just one-step reaction.By using inexpensive chlorine gas as the chlorinating agent,it avoids lengthy procedural steps and the generation of acid-base waste liquids.Based on this,we propose a novel carbochlorination process for bastnaesite involving a fluorine-fixing agent.Thermodynamic data for the carbochlorination process of bastnaesite were calculated using the group contribution method.Thermodynamic feasibility was verified through Gibbs free energy.The effects of different chlorination times,fluorine-fixing agent dosages,chlorine flow rates,and chlorination temperatures on the carbochlorination process of bastnaesite were investigated.Experimental studies showed that under optimal chlorination conditions,a temperature of 800℃,a duration of 60 min,a fluorine-fixing agent dosage of 10%,and a chlorine flow rate of 10 L·min^(−1),the chlorination rates of rare-earth elements,Ca,Ba,and Fe in bastnaesite reached 96%,99%,98%,and 99%,respectively.The reaction mechanism was explored and analyzed based on characterization results such as mineral phase composition,micromorphology and thermogravimetry of water-washed residues under different chlorination conditions.Additionally,kinetic experiments were conducted at varying reaction temperatures and chlorine flow rates,revealing that the carbon-chlorination process is primarily controlled by chemical reactions. 展开更多
关键词 Rare earths Carbochlorination THERMODYNAMICS Separation KINETICS
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Comprehensive insights into the organic/inorganic composition separation of sewer sediment by various driving forces:Separation pathway and thermodynamic evolution
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作者 Heliang Pang Jiangbo Ding +3 位作者 Yan Wang Jiawei Liu Qiwen Qin Jinsuo Lu 《Journal of Environmental Sciences》 2026年第1期785-796,共12页
With the legislative development,the organic and inorganic composition separation has become the primary requirement for sewer sediment disposal,however the relevant technology has been rarely reported and the driving... With the legislative development,the organic and inorganic composition separation has become the primary requirement for sewer sediment disposal,however the relevant technology has been rarely reported and the driving mechanism was still unclear.In this study,direct disintegration of biopolymers and indirect broken of connection point were investigated on the hydrolysis and component separation.Three typical sewer sediment treatment approaches,i.e.,alkaline,thermal and cation exchange treatments were proposed,which represented the hydrolysis-driving forces of chemical hydrolysis,physical hydrolysis and innovative cation bridging break-age.The results showed that the organic and inorganic separation rates of sewer sediment driven by alkaline,thermal and cation exchange treatments reached 21.26%,23.80%,and 19.56%-48.0%,respectively,compared to 4.43%in control.The secondary structure of proteins was disrupted,transitioning from𝛼α-helix to𝛽β-turn and random coil.Meanwhile,much biopolymers were released from solid to the liquid phase.From thermody-namic perspective,sewer sediment deposition was controlled by short-range interfacial interactions described by extended Derjaguin-Landau-Verwey-Overbeek theory.Additionally,the separation of organic and inorganic components was positively correlated with the thermodynamic parameters(Corr=0.87),highlighted the robust-ness of various driving forces.And the flocculation energy barriers were 2.40(alkaline),1.60 times(thermal),and 4.02–4.97 times(cation exchange)compared to control group.The findings revealed the contrition differ-ence of direct disintegration of gelatinous biopolymers and indirect breakage of composition connection sites in sediment composition separation,filling the critical gaps in understanding the specific mechanisms of sediment biopolymer disintegration and intermolecular connection breakage. 展开更多
关键词 Sewer sediment Component separation Directly disintegration Indirect broken Thermodynamic Biopolymer
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Seismic response of adjacent buildings considering structure-soil-structure interaction
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作者 Hamzeh Ahmadi Reza Alinejad Maziar Fahimi Farzam 《Earthquake Engineering and Engineering Vibration》 2026年第1期255-277,共23页
This study examines the dynamic response of two adjacent 9-and 20-story benchmark steel buildings subjected to six near-fault earthquake records.Two-dimensional numerical models were employed to account for the comple... This study examines the dynamic response of two adjacent 9-and 20-story benchmark steel buildings subjected to six near-fault earthquake records.Two-dimensional numerical models were employed to account for the complexities of structure-soil-structure interaction(SSSI).The research focuses on the separation gap between the buildings and the effects of pounding while considering Fixed Base(FB)and SSSI models,evaluated according to UBC 94 and ASCE 7-16 seismic codes.Key findings reveal that pounding occurs with the UBC 94 separation gap when earthquake frequency aligns with system frequency,leading to increased column stresses in the 9-story building.In contrast,the ASCE 7-16 standard effectively prevents pounding in both the FB and SSSI models.Additionally,drifts and displacements of lower floors in SSSI models exceed the allowable limits of ASCE 7-16,underscoring the impact of soil-structure interaction on seismic response. 展开更多
关键词 structure-soil-structure interaction separation gap POUNDING nonlinear analysis near-fault earthquake seismic response
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Occurrence modes and comprehensive utilization of critical metal resources associated with coal:A review
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作者 Qin Zhang Wei Cheng +6 位作者 Tiebin Zhang Hongbo Liu Jiwei Yuan Aoao Chen Tingshun Wang Qian Liu Jianghe Wang 《International Journal of Mining Science and Technology》 2026年第2期277-293,共17页
Coal serves not only as a crucial energy resource but also as a significant reservoir of critical metal elements,including Lithium(Li),Gallium(Ga),Germanium(Ge),and rare earth elements(REE).This paper provides a syste... Coal serves not only as a crucial energy resource but also as a significant reservoir of critical metal elements,including Lithium(Li),Gallium(Ga),Germanium(Ge),and rare earth elements(REE).This paper provides a systematic review of the enrichment characteristics,occurrence modes,and comprehensive utilization potential of these critical metals in coal.Globally,the distribution of these metal resources exhibits significant regional heterogeneity.While the concentration in most coals falls below industrial cut-off grades,anomalous enrichment in specific coal basins results in Li,Ga,Ge,and REE concentrations far exceeding global averages,highlighting their considerable potential as unconventional metal deposits.The occurrence modes of these metals are diverse:Li is primarily hosted in mineral phases;Ga exists in inorganic,organic,and complex forms;Ge shows a strong association with organic matter;and REE are mainly present in adsorbed/isomorphic forms within clay minerals,while also displaying organic affinity.Direct extraction of metals from raw coal is often cost-prohibitive;effective recovery is therefore more feasible when integrated with coal processing.Metals are further enriched in solid wastes such as coal gangue,fly ash,and bottom ash,from which recovery is more economically and technically viable.Current comprehensive utilization primarily employs integrated mineral processing-hydrometallurgy approaches.Future research should focus on elucidating the precise occurrence forms of metals in coal and solid wastes,optimizing pre-treatment methods,and selecting effective activators and leachants.Advancing the synergistic extraction and green recovery of multiple associated resources from coal and its by-products is essential for achieving high-value,comprehensive utilization of coal-based resources. 展开更多
关键词 Coal-associated resources Lithium GALLIUM GERMANIUM Rare carth elements Extraction and separation
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The surface binding and energy issues in the rational design of separators for Li||S batteries
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作者 Hongfang Du Lijing Wang +8 位作者 Shuyu Cheng Chao Wu Sheng Yang Yang Liu Yi Zhao Dandan Cui Shaowei Zhang Shixue Dou Liangxu Lin 《Journal of Energy Chemistry》 2026年第1期987-1013,I0021,共28页
Lithium-sulfur batteries(LSBs)represent a next-generation energy storage technology,but widespread applications are restricted by the shuttle of lithium polysulfides(LiPSs).The rational design of separators has been d... Lithium-sulfur batteries(LSBs)represent a next-generation energy storage technology,but widespread applications are restricted by the shuttle of lithium polysulfides(LiPSs).The rational design of separators has been demonstrated to be one of the most efficient and cost-effective strategies to curb the shuttle effect,and tremendous research progress has been achieved.The efficiency of a separator depends on its interaction with LiPSs,which is governed by the surface energy and binding strength.Despite several review works that have been reported to advance the separators,most of them primarily focus on active material innovation and construction.The most crucial issues of surface binding energy have not been systematically reviewed,limiting the precise design of efficient separators.In this review,fundamentals related to surface energy and binding interactions with LiPSs are comprehensively analyzed and discussed.With surface binding and energy main lines,the advancements in separator engineering strategies are elaborately summarized and discussed.Moreover,techniques for evaluating affinity to LiPSs are thoroughly analyzed to avoid any ambiguities in measurement.Based on the research context,valuable research directions are suggested to construct efficient separators.This work provides guidelines to regulate the surface binding and energy of separators for high-performance LSBs. 展开更多
关键词 Lithium-sulfur batteries SEPARATOR Surface binding affinity Surface energy Rational design
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Efficient leukocyte removal and enhanced biocompatibility using PVDF membranes prepared by vapor-induced phase separation
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作者 Ziqi Jin Shuang Yao +5 位作者 Liang Li Siyuan Sun Yue Zhou Jie Zhou Zhaohui Wang Zhaoliang Cui 《Chinese Journal of Chemical Engineering》 2026年第1期1-12,共12页
To develop an efficient filter for removing white blood cells from whole blood,hydrophilic large-pore blended membranes of poly(vinylidene fluoride)(PVDF),polyvinyl pyrrolidone and polyethylene glycol,with good biocom... To develop an efficient filter for removing white blood cells from whole blood,hydrophilic large-pore blended membranes of poly(vinylidene fluoride)(PVDF),polyvinyl pyrrolidone and polyethylene glycol,with good biocompatibility,were prepared using the process of vapor-induced phase separation at various PVDF concentrations.The results demonstrated that at a PVDF mass concentration of 14%,the membrane had increased surface roughness,significantly enhanced hydrophilicity and wettability,and a wetting time of 8 s.The surface roughness of the membrane was also reduced to 31.637 nm.Furthermore,hemolysis rate and protein adsorption tests indicated that the blended membranes possessed excellent biocompatibility.They were reduced to 2.48%and 34.44μg·cm^(−2),respectively.The pore size of the fabricated membrane was relatively large,which reached approximately 8μm respectively,satisfying the filtration requirements.Lastly,the effects of different temperatures and multi-layered filters on leukocyte removal and the retention of red blood cells and platelets from whole blood were evaluated.The results revealed that the leukocyte removal rate was highest at 4℃ and with three membrane layers,the leukocyte removal rate was highest,reaching 98.36%,while the RBC and platelet content remained nearly unchanged compared with the original blood.This study provides a new approach for blood cell separation that is expected to play a significant role in medical fields such as blood transfusion demonstrating great potential for application and innovation. 展开更多
关键词 Polyvinylidene fluoride membrane Vapor-induced phase separation Pore size Leukocyte filtration Hemocompatibility
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Unveiling the high-activity origins of BiVO_(4)-Zn tandems for CO_(2)photoreduction
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作者 Peng Wang Yong Ding Yingpu Bi 《Journal of Energy Chemistry》 2026年第1期618-624,I0014,共8页
Herein,we demonstrated the integration of BiVO_(4)-based photoanode with metallic Zn cathode for high-performance CO_(2)reduction,and a record CO production rate of 113.32μmol cm^(−2)h^(−1)with a FECO of 90.57%has be... Herein,we demonstrated the integration of BiVO_(4)-based photoanode with metallic Zn cathode for high-performance CO_(2)reduction,and a record CO production rate of 113.32μmol cm^(−2)h^(−1)with a FECO of 90.57%has been achieved under simulated sunlight(AM 1.5 G,100 mW),accompanying with an excellent stability.More importantly,the direct observation of spatial charge separation/transfer and dynamic surface catalysis for both H_(2)O oxidation and CO_(2)reduction has been firstly achieved by the combination of in situ X-ray photoelectron spectroscopy(IS-XPS)with Fourier transform infrared reflection(IS-FTIR).Under light irradiation,the electron-hole pairs have been generated on BiVO_(4) photoanode,and holes rapidly transfer to photoanode surfaces for participating in oxygen evolution reaction(OER)through the formation of*OH and*OOH intermediates.Simultaneously,the proton-coupled electron transfer to the Zn cathode surfaces drive the reduction of adsorbed CO_(2)molecules into CO via the formation*COOH and*CO intermediates.Thereby,this work offers new insights into fundamental understanding of CO_(2)reduction process,which facilitates the future development of highly efficient carbon fixation systems. 展开更多
关键词 Surface catalysis Charge separation Structure Dynamics CO_(2)photoreduction
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Anionically-Reinforced Nanocellulose Separator Enables Dual Suppression of Zinc Dendrites and Polyiodide Shuttle for Long-Cycle Zn-I_(2) Batteries
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作者 Wenhui Liu Hong Ma +4 位作者 Lingli Zhao Weiwei Qian Bo Liu Jizhang Chen Yagang Yao 《Nano-Micro Letters》 2026年第2期569-583,共15页
Zn-I_(2) batteries have emerged as promising next-generation energy storage systems owing to their inherent safety,environmental compatibility,rapid reaction kinetics,and small voltage hysteresis.Nevertheless,two crit... Zn-I_(2) batteries have emerged as promising next-generation energy storage systems owing to their inherent safety,environmental compatibility,rapid reaction kinetics,and small voltage hysteresis.Nevertheless,two critical challenges,i.e.,zinc dendrite growth and polyiodide shuttle effect,severely impede their commercial viability.To conquer these limitations,this study develops a multifunctional separator fabricated from straw-derived carboxylated nanocellulose,with its negative charge density further reinforced by anionic polyacrylamide incorporation.This modification simultaneously improves the separator’s mechanical properties,ionic conductivity,and Zn^(2+)ion transfer number.Remarkably,despite its ultrathin 20μm profile,the engineered separator demonstrates exceptional dendrite suppression and parasitic reaction inhibition,enabling Zn//Zn symmetric cells to achieve impressive cycle life(>1800 h at 2 m A cm^(-2)/2 m Ah cm^(-2))while maintaining robust performance even at ultrahigh areal capacities(25 m Ah cm^(-2)).Additionally,the separator’s anionic characteristic effectively blocks polyiodide migration through electrostatic repulsion,yielding Zn-I_(2) batteries with outstanding rate capability(120.7 m Ah g^(-1)at 5 A g^(-1))and excellent cyclability(94.2%capacity retention after 10,000 cycles).And superior cycling stability can still be achieved under zinc-deficient condition and pouch cell configuration.This work establishes a new paradigm for designing high-performance zinc-based energy storage systems through rational separator engineering. 展开更多
关键词 Zinc-iodine batteries Nanocellulose separators Carboxyl functional groups Polyiodide shuttle effect Dendrite suppression
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Heat-resistant Microporous Star-shaped Casting Polyurethane for Airless Electric Bicycle Tires
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作者 Chao-Yang Yuan Lei Shi +6 位作者 Shang-Chao Ji Hai-Long Chen Xiao Tong Zi-Ying Hao Xiao-Da Pan Xian-Ze Yin Long Zheng 《Chinese Journal of Polymer Science》 2026年第2期474-484,I0014,共12页
Airless tires are essential for enhancing the safety,reliability,and convenience of maintenance of electric bicycles.Polyurethane(PU)is considered a promising candidate for such applications owing to its versatile pro... Airless tires are essential for enhancing the safety,reliability,and convenience of maintenance of electric bicycles.Polyurethane(PU)is considered a promising candidate for such applications owing to its versatile properties.However,their use is limited by insufficient heat resistance and excessive dynamic heat generation under cyclic loading.In this study,star-shaped trifunctional polypropylene glycerol(PPG3)was incorporated into conventional poly(tetramethylene glycol)(PTMG)and 4,4'-methylenediphenyl diisocyanate(MDI)-based systems to construct microporous star-shaped casting polyurethanes(SCPU),with water serving as a green foaming agent.Unlike conventional small-molecule trifunctional crosslinkers that create junctions within hard segment domains,PPG3 introduces long flexible arms between the hard segments,anchoring the crosslinking points at its molecular core.The large steric hindrance of PPG3 effectively suppresses soft segment crystallization and lowers the degree of microphase separation,whereas the crosslinked network restricts chain mobility,thereby reducing dynamic heat generation.These structural features also enhance the heat resistance,yielding a softening temperature of 183℃,which is 30.9%higher than that of polyurethane without PPG3.When applied to airless tires by casting SCPU into rubber treads,the fabricated hybrid airless tires achieved a rolling distance of over 3000 km under a load of 65 kg at 25km/h without structural failure,satisfying practical performance requirements.This strategy offers a simple,solvent-free,and environmentally friendly process,underscoring the potential of SCPU for scalable production of high-performance airless tires. 展开更多
关键词 Microporous star-shaped casting polyurethane Microphase separation Heat resistance Airless tire
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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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Preparation of a homochiral metal-organic cage and its bonded silicas for efficient enantioseparation in high-performance liquid chromatography and gas chromatography
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作者 Jun-Hui Zhang Rui-Xue Liang +5 位作者 Bin Huang Li-Qin Yu Juan Chen Bang-Jin Wang Sheng-Ming Xie Li-Ming Yuan 《Chinese Chemical Letters》 2026年第1期520-526,共7页
Developing a chiral material as versatile and universal chiral stationary phase(CSP) for chiral separation in diverse chromatographic techniques simultaneously is of great significance.In this study,we demonstrated fo... Developing a chiral material as versatile and universal chiral stationary phase(CSP) for chiral separation in diverse chromatographic techniques simultaneously is of great significance.In this study,we demonstrated for the first time that a chiral metal-organic cage(MOC),[Zn_(6)M_(4)],as a universal chiral recognition material for both multi-mode high-performance liquid chromatography(HPLC) and capillary gas chromatography(GC) enantioseparation.Two novel HPLC CSPs with different bonding arms(CSP-A with a cationic imidazolium bonding arm and CSP-B with an alkyl chain bonding arm) were prepared by clicking of functionalized chiral MOC [Zn_(6)M_(4)] onto thiolated silica via thiol-ene click chemistry.Meanwhile,a capillary GC column statically coated with the chiral MOC [Zn_(6)M_(4)] was also fabricated.The results showed that the chiral MOC exhibits excellent enantioselectivity not only in normal phase HPLC(NP-HPLC) and reversed phase(RP-HPLC) but also in GC,and various racemates were well separated,including alcohols,diols,esters,ketones,ethers,amines,and epoxides.Importantly,CSP-A and CSP-B are complementary to commercially available Chiralcel OD-H and Chiralpak AD-H columns in enantioseparation,which can separate some racemates that could not be or could not well be separated by the two widely used commercial columns,suggesting the great potential of the two prepared CSPs in enantioseparation.This work reveals that the chiral MOC is potential versatile chiral recognition materials for both HPLC and GC,and also paves the way to expand the potential applications of MOCs. 展开更多
关键词 Chiral metal-organic cage Chiral stationary phase Chiral separation High-performance liquid chromatography Gas chromatography
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The Impact of Mother-Infant Separation on the Physical and Mental Health of Women with High-Risk Pregnancies and Corresponding Nursing Strategies
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作者 Qing Yang 《Journal of Clinical and Nursing Research》 2026年第1期145-152,共8页
Objective:To analyze the impact of maternal-infant separation on the physical and mental state of high-risk pregnancy patients and explore the clinical efficacy of targeted nursing interventions.Methods:A total of 80 ... Objective:To analyze the impact of maternal-infant separation on the physical and mental state of high-risk pregnancy patients and explore the clinical efficacy of targeted nursing interventions.Methods:A total of 80 high-risk pregnancy patients treated in our hospital from January 2023 to January 2024 were selected as the study subjects.These patients were randomly divided into an observation group and a control group(40 cases each)using a random number table.The control group received routine high-risk pregnancy nursing care,while the observation group received specialized maternal-infant separation nursing interventions in addition to routine care.The psychological and physiological states and nursing satisfaction of the two groups were compared before and after the intervention.Results:The SAS scores,SDS scores,and sleep quality scores of the observation group were significantly lower than those of the control group,with statistically significant differences(p<0.05).The incidence of postpartum hemorrhage in the observation group was significantly lower than that in the control group,and the initiation time of lactation was significantly earlier than that in the control group,with both differences being statistically significant(p<0.05).The nursing satisfaction of the observation group was significantly higher than that of the control group(80%vs.32/40),with a statistically significant difference(p<0.05).Conclusion:Maternal-infant separation exacerbates anxiety and depression in high-risk pregnancy patients,reduces sleep quality,increases the risk of postpartum hemorrhage,and delays the initiation of lactation.Specialized nursing interventions for maternal-infant separation can improve the physical and mental state of high-risk pregnancy patients,reduce the incidence of postpartum complications,and enhance nursing satisfaction,making them worthy of clinical application and promotion. 展开更多
关键词 Mother-infant separation High-risk pregnancy women Physical and mental health Nursing strategies
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Block-Wise Sliding Recursive Wavelet Transform and Its Application in Real-Time Vehicle-Induced Signal Separation
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作者 Jie Li Nan An Youliang Ding 《Structural Durability & Health Monitoring》 2026年第1期1-22,共22页
Vehicle-induced response separation is a crucial issue in structural health monitoring(SHM).This paper proposes a block-wise sliding recursive wavelet transform algorithm to meet the real-time processing requirements ... Vehicle-induced response separation is a crucial issue in structural health monitoring(SHM).This paper proposes a block-wise sliding recursive wavelet transform algorithm to meet the real-time processing requirements of monitoring data.To extend the separation target from a fixed dataset to a continuously updating data stream,a block-wise sliding framework is first developed.This framework is further optimized considering the characteristics of real-time data streams,and its advantage in computational efficiency is theoretically demonstrated.During the decomposition and reconstruction processes,information from neighboring data blocks is fully utilized to reduce algorithmic complexity.In addition,a delay-setting strategy is introduced for each processing window to mitigate boundary effects,thereby balancing accuracy and efficiency.Simulated signal experiments are conducted to determine the optimal delay configuration and to verify the algorithm’s superior performance,achieving a lower Root Mean Square Error(RMSE)and only 0.0249 times the average computational time compared with the original algorithm.Furthermore,strain signals from the Lieshi River Bridge are employed to validate the method.The proposed algorithm successfully separates the static trend from vehicle-induced responses in real time across different sampling frequencies,demonstrating its effectiveness and applicability in real-time bridge monitoring. 展开更多
关键词 Wavelet transform vehicle-induced signal separation real-time structure monitoring
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