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EFFECT OF DILUENTS ON CRYSTALLIZATION OF POLY(VINYLIDENE FLUORIDE) AND PHASE SEPARATED STRUCTURE IN A TERNARY SYSTEM via THERMALLY INDUCED PHASE SEPARATION 被引量:1
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作者 徐又一 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第3期291-298,共8页
The phase diagram of a ternary system of PVDF,dibutyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP) was determined in terms of a pseudo binary system with the same polymer concentration and different DBP conte... The phase diagram of a ternary system of PVDF,dibutyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP) was determined in terms of a pseudo binary system with the same polymer concentration and different DBP content in diluent mixture.The experimental results showed that as the DBP content increased in diluent mixture,the phase separation changed from liquid-liquid phase separation to solid-liquid phase separation,and both the cloudy point for L-L phase separation and crystallization temperature shifted... 展开更多
关键词 Phase separation CRYSTALLIZATION Membrane PVDF Interaction
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Organic solvent nanofiltration membranes for separation in non-polar solvent system 被引量:1
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作者 Shuyun Gu Siyao Li Zhi Xu 《Green Energy & Environment》 2025年第2期244-267,共24页
Membrane technology holds significant potential for augmenting or partially substituting conventional separation techniques,such as heatdriven distillation,thereby reducing energy consumption.Organic solvent nanofiltr... Membrane technology holds significant potential for augmenting or partially substituting conventional separation techniques,such as heatdriven distillation,thereby reducing energy consumption.Organic solvent nanofiltration represents an advanced membrane separation technology capable of discerning molecules within a molecular weight range of approximately 100-1000 Da in organic solvents,offering low energy requirements and minimal carbon footprints.Molecular separation in non-polar solvent system,such as toluene,n-hexane,and n-heptane,has gained paramount importance due to their extensive use in the pharmaceutical,biochemical,and petrochemical industries.In this review,we presented recent advancements in membrane materials,membrane fabrication techniques and their promising applications for separation in nonpolar solvent system,encompassing hydrocarbon separation,bioactive molecule purification and organic solvent recovery.Furthermore,this review highlighted the challenges and opportunities associated with membrane scale-up strategies and the direct translation of this promising technology into industrial applications. 展开更多
关键词 Organic solvent nanofiltration Membranes Membrane separation Non-polar solvent system Petrochemical and pharmaceutical application
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Numerical simulation 0n the influence of different median strip types in the separated highway subgrade cross section on the transport law of wind-sand flow
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作者 ZHANG Jing LI Shengyu +1 位作者 SUN Yunlong XIA Tian 《Journal of Mountain Science》 2025年第5期1707-1722,共16页
To mitigate the sand burial of highways in sandy regions,a separated subgrade design was widely adopted in the embankments of high-grade highways,but the problem of sand deposition on subgrade slopes and pavements sti... To mitigate the sand burial of highways in sandy regions,a separated subgrade design was widely adopted in the embankments of high-grade highways,but the problem of sand deposition on subgrade slopes and pavements still happens frequently.Based on the theory of wind-sand two-phase flow,this paper constructed a three-dimensional model of the separated subgrade,the wind-sand flow transport law around the subgrade with varying median strip widths and concave depths was simulated by Fluent software.After comparison and analysis of seven subgrade models,the flow field distribution,wind speed horizontal variation,and erosion-deposition characteristics were investigated.The findings are as follows:(1)The width of the median strip in the separated subgrade had significant influences on the wind-sand flow.The smooth passage of wind-sand flow over the road surface was facilitated with the increase of the median strip width.However,sand deposition in the median strip happened.It can lead to secondary sand damage of downwind subgrade and increase the work load of road sand removal for subsequent maintenance.(2)The obstruction to airflow and sand accumulation was aggravated with greater concave depth of the median strip.Therefore,it is advisable to minimize the concave depth of the median strip in case of more sand damage.(3)A median strip width exceeding 12 m(possibly without guardrails)for an integral embankment without enough road land is recommended.Conversely,median strip width of over 40 m for separate subgrade with unrestricted land is suggested.(4)In the case of sand deposition in the existing separated subgrade,the median strip can be filled by sand deposition or other materials,then was covered with gravel to form a flat ground like Gobi smooth surface,which can let the wind-blown sand flow pass through the subgrade section without sand deposition. 展开更多
关键词 Highway engineering separated subgrade Median strip Numerical simulation Embankment wind-sand flow
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Interfacial adsorption and reactivity of exact separation of sphalerite and pyrite by ferrophilic inhibitors in EX−Cu(Ⅱ)system
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作者 Wen-chao DONG Run-qing LIU +2 位作者 Chang-tao WANG Zheng-qiang CAO Wei SUN 《Transactions of Nonferrous Metals Society of China》 2025年第5期1662-1678,共17页
Tetrasodium iminodisuccinate(IDS)was used as an inhibitor in the separation of sphalerite and pyrite in the EX−Cu(II)(ethyl xanthate and Cu2+)system.The flotation test results demonstrated that IDS can effectively sep... Tetrasodium iminodisuccinate(IDS)was used as an inhibitor in the separation of sphalerite and pyrite in the EX−Cu(II)(ethyl xanthate and Cu2+)system.The flotation test results demonstrated that IDS can effectively separate sphalerite and pyrite under low alkaline conditions.Furthermore,high-quality zinc concentrates with a Zn grade of 58.48%and a recovery of 91.24%through mixed mineral flotation were obtained.The fundamental mechanisms were investigated through surface wettability tests,adsorption capacity tests,LEIS,FTIR,and XPS.The results confirmed that IDS prevents the adsorption of EX on the surface of pyrite,thereby reducing the response and reactivity of pyrite.The introduction of IDS causes the detachment of Cu2+from the Cu-activated pyrite surface.This process allowed IDS to chelate with the Fe sites on the surface of pyrite through the-COO-and N-centered active groups.By contrast,IDS exhibits weaker adhesion on the surface of Cu-activated sphalerite,making it easily displaced by EX through competitive adsorption. 展开更多
关键词 interfacial adsorption REACTIVITY SEPARATION SPHALERITE PYRITE tetrasodium iminodisuccinate
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The transformative potential of cellulose in energy storage systems
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作者 Longjun Chang Zhaoxin Li +1 位作者 Zhiyuan Yan Qing Li 《Energy Materials and Devices》 2025年第4期1-18,共18页
Cellulose-based materials have attracted growing interest in the development of advanced energy storage systems owing to their intrinsic sustainability,tunable physicochemical properties,and structural versatility.Thi... Cellulose-based materials have attracted growing interest in the development of advanced energy storage systems owing to their intrinsic sustainability,tunable physicochemical properties,and structural versatility.This review systematically summarizes the key features of cellulose from the perspectives of synthesis,physicochemical characteristics,and structural design,highlighting its unique functionality and adaptability.Furthermore,the roles of cellulose in four critical battery components,i.e.,electrode,solid electrolyte interphase,separator,and electrolyte,are comprehensively discussed,emphasizing the properties aligning with the specific requirements of each component.Finally,potential research directions are proposed to guide future development.This review provides a comprehensive framework for understanding the transformative potential of cellulose in sustainable electrochemical energy storage systems as well as a guideline for future studies. 展开更多
关键词 CELLULOSE ELECTRODE solid electrolyte interphase SEPARATOR ELECTROLYTE
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Recyclable and Degradable Poly(p-dioxanone)-based Copolymer with Enhanced Mechanical Properties by Microphase-separated Interface Crystallization
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作者 Li Huang Jie Zhang +2 位作者 Si-Chong Chen Gang Wu Yu-Zhong Wang 《Chinese Journal of Polymer Science》 2025年第6期933-945,I0007,共14页
The development of degradable and chemically recyclable polymers is a promising strategy to address pressing environmental and resource-related challenges.Despite significant progress,there is a need for continuous de... The development of degradable and chemically recyclable polymers is a promising strategy to address pressing environmental and resource-related challenges.Despite significant progress,there is a need for continuous development of such recyclable polymers.Herein,PPDOPLLA-PU copolymers were synthesized from poly(p-dioxanone)-diol(PPDO-diol)and poly(L-lactide)-diol(PLLA-diol)by chain extension reaction.The chemical structures and microphase structures of PPDO-PLLA-PU were characterized,and their crystalline properties,mechanical properties,and degradation behaviors were further investigated.Significantly,the distribution of PLLA phase in the copolymer matrix showed a rod-like microstructure with a slight orientation,despite the thermodynamic incompatibility of PPDO and PLLA segments.Moreover,on the basis of this microphase separation,PPDO spherulites can crystallize using the interface of the two phases as nucleation sites.Accordingly,the combined effect of above two contributes to the enhanced mechanical properties.In addition,PPDO-PLLA-PU copolymers have good processability and recyclability,making them valuable for a wide range of applications. 展开更多
关键词 RECYCLABLE DEGRADABLE Poly(p-dioxanone) Microphase separation
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Exosomes separation with aqueous two-phase systems from bovine milk
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作者 Jingjing Sun Ruoque Mao +2 位作者 Xiaoqian Fu Shanjing Yao Dongqiang Lin 《Chinese Journal of Chemical Engineering》 2025年第5期1-10,共10页
The exosomes hold significant potential in disease diagnosis and therapeutic interventions.The objective of this study was to investigate the potential of aqueous two-phase systems(ATPSs)for the separation of bovine m... The exosomes hold significant potential in disease diagnosis and therapeutic interventions.The objective of this study was to investigate the potential of aqueous two-phase systems(ATPSs)for the separation of bovine milk exosomes.The milk exosome partition behaviors and bovine milk separation were investigated,and the ATPSs and bovine milk whey addition was optimized.The optimal separation conditions were identified as 16%(mass)polyethylene glycol 4000,10%(mass)dipotassium phosphate,and 1%(mass)enzymatic hydrolysis bovine milk whey.During the separation process,bovine milk exosomes were predominantly enriched in the interphase,while protein impurities were primarily found in the bottom phase.The process yielded bovine milk exosomes of 2.0×10^(11)particles per ml whey with high purity(staining rate>90%,7.01×10^(10)particles per mg protein)and high uniformity(polydispersity index<0.03).The isolated exosomes were characterized and identified by transmission electron microscopy,zeta potential and size distribution.The results demonstrated aqueous two-phase extraction possesses a robust capability for the enrichment and separation of exosomes directly from bovine milk whey,presenting a novel approach for the large-scale isolation of exosomes. 展开更多
关键词 Aqueous two-phase extraction Bovine milk exosomes SEPARATION PURIFICATION
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An intelligent separated zone oil production technology based on electromagnetic coupling principle
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作者 YANG Qinghai LIAO Chenglong +5 位作者 JIA Deli ZHU Yingjun YU Chuan KONG Lingwei YU Yang DU Kai 《Petroleum Exploration and Development》 2025年第1期230-244,共15页
To address the challenges associated with existing separated zone oil production technologies,such as incompatibility with pump inspection operations,short effective working life,and poor communication reliability,an ... To address the challenges associated with existing separated zone oil production technologies,such as incompatibility with pump inspection operations,short effective working life,and poor communication reliability,an innovative electromagnetic coupling intelligent zonal oil production technology has been proposed.The core and accessory tools have been developed and applied in field tests.This technology employs a pipe string structure incorporation a release sub,which separates the production and allocation pipe strings.When the two strings are docked downhole,electromagnetic coupling enables close-range wireless transmission of electrical power and signals between the strings,powering multiple downhole intelligent production allocators(IPAs)and enabling two-way communication.Core tools adapted to the complex working conditions downhole were developed,including downhole electricity&signal transmission equipment based on electromagnetic coupling(EST),IPAs,and ground communication controllers(GCCs).Accessory tools,including large-diameter release sub anchor and cable-crossing packers,have also been technically finalized.Field tests conducted on ten wells in Daqing Oilfield demonstrated that the downhole docking of the two strings was convenient and reliable,and the EST worked stably.Real-time monitoring of flow rate,pressure and temperature in separate layers and regulation of zonal fluid production were also achieved.This technology has enhanced reservoir understanding and achieved practical production results of increased oil output with reduced water cut. 展开更多
关键词 separated zone oil production electromagnetic coupling wireless transmission of electrical power wireless transmission of signal real-time downhole monitoring collaborative regulation of injection and production oil production stabilization and water cut control
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Competitive behaviors between tungsten and iron in TBP-HCl-H_(2)O extraction system
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作者 Li-qin DENG Xu-heng LIU +4 位作者 Xing-yu CHEN Jiang-tao LI Li-hua HE Feng-long SUN Zhong-wei ZHAO 《Transactions of Nonferrous Metals Society of China》 2025年第3期990-999,共10页
The distribution and competitive behaviors of phosphotungstic acid and ferric chloride in the TBP-HCl-H_(2)O system were investigated by controlling the extractant concentration and the solution environment.The result... The distribution and competitive behaviors of phosphotungstic acid and ferric chloride in the TBP-HCl-H_(2)O system were investigated by controlling the extractant concentration and the solution environment.The results revealed that phosphotungstic acid exhibited a strong affinity for TBP with decreasing TBP concentration.Higher acidity significantly improved the W extraction efficiency with TBP,and the lower Cl^(-)concentration reduced the extraction efficiency of Fe.As the organic phase approached saturation point,phosphotungstic acid competitively displaced Fe to combine with TBP.The hydrogen bond structure(P=O·HO-P-W-O)between phosphotungstic acid and TBP was characterized by FT-IR,and the salting-out effect induced by FeCl_(3) was elucidated.In summary,high acidity is beneficial for exhaustive extraction of W,and an effective W/Fe separation can be achieved by reducing the concentrations of TBP and Cl^(-). 展开更多
关键词 extraction tri-butyl phosphate tungsten/iron separation distribution equilibrium competitive behavior
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Solvent extraction systems for selective isolation of light rare earth elements with high selectivity for Sm and La
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作者 Hossein Salehi Samane Maroufi +1 位作者 Rasoul Khayyam Nekouei Veena Sahajwalla 《Rare Metals》 2025年第3期2071-2084,共14页
This study details a comprehensive approach focusing on the effective separation of light rare earth elements(REEs)via solvent extraction technique.A stock solution containing lanthanum,cerium,neodymium,praseodymium,a... This study details a comprehensive approach focusing on the effective separation of light rare earth elements(REEs)via solvent extraction technique.A stock solution containing lanthanum,cerium,neodymium,praseodymium,and samarium was prepared by dissolving their pure mixed oxide(reclaimed from spent Ni-MH batteries)in a diluted HCl solution.Key extractants,including bis(2,4,4-trimethylpentyl)phosphinic acid(Cyanex 272),Cyanex 572,trialkylphosphine oxide(Cyanex 923),and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester(PC 88A),along with tributyl phosphate(TBP)as a phase modifier,were utilized to form organic systems.The extraction behavior and separability of these systems at various pH levels as well as their extraction mechanisms were investigated.The results demonstrated a direct relationship between the extraction trend and the experimental pH value,with enhanced selectivity when TBP was added.Notably,Nd and Pr exhibited similar extraction behaviors,with minor deviations from Ce,making their separation difficult to achieve.Sm extraction followed a distinct trend,allowing for its separation from other elements at pH≤2.In contrast,La exhibited a low affinity for coordination with extractants when pH was≤3.5,facilitating the separation of other elements from La,which could then be isolated in the raffinate.Among the studied organic systems,combinations of Cyanex 572 and PC 88A with TBP demonstrated superior performance in element separation.Optimum separation factors were calculated withβ_(Ce/La)=12,βNd/La=87,β_(Pr/La)=127,andβ_(Sm/La)=3191 for the former,andβ_(Sm/Ce)=54,β_(Sm/Nd)=20,andβ_(Sm/Pr)=14 for the latter.These findings provide valuable insights for selecting extraction systems and designing experiments for the effective solvent extraction separation of light REEs from their mixture. 展开更多
关键词 Solvent extraction Rare earth elements Individual separation Ni-MH batteries Extraction mechanism
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Towards Sustainable Urban Water System:A Strategic Approach to Advance Decarbonizing Water Management
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作者 Xinyu Pan Yumeng Zhao +3 位作者 Xinlu Lin Nianyi Zhao Meng Sun Jun Ma 《Engineering》 2025年第7期31-39,共9页
The decarbonization of urban water systems is critical for achieving global climate goals,and reducing the carbon intensity of urban water systems necessitates a paradigm shift from traditional end-of-pipe treatment a... The decarbonization of urban water systems is critical for achieving global climate goals,and reducing the carbon intensity of urban water systems necessitates a paradigm shift from traditional end-of-pipe treatment approaches to alternative technological solutions and holistic planning.This study explores a comprehensive strategy for achieving sustainable urban water management that integrates a decentral-ized water system(DWS),source separation,and low-carbon water treatment technologies.DWS is fun-damental to implementing a sustainable urban water system.This study addresses the social contexts,costs,approaches,and benefits associated with DWS implementation,emphasizing the importance of its construction.Subsequently,the analysis focuses on the on-site source separation of grey water,feces,and yellow water in the DWS,which serves as the primary approach for wastewater reuse and N/P recov-ery for a sustainable urban water system.Following source separation,low-carbon water treatment tech-nologies based on resource conservation and recovery are thoroughly discussed.Specifically,resource conservation can be achieved through rainwater control,efficiency improvements,and low energy con-sumption,while resource recovery can be attained through carbon capturing and energy/nutrient recov-ery.Overall,in response to the challenges in current urban water management,this study proposes a comprehensive strategy that supports a sustainable urban water system,providing theoretical guidance for reducing carbon emissions. 展开更多
关键词 Sustainable urban water system DECENTRALIZATION Source separation Low-carbon water treatment
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Enhanced fluid-flow-field and electric-field synergistic interaction mechanism for lithium-ion separation in dilute solutions:A numerical analysis of electrochemically switched ion exchange system
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作者 Kangjun Ji Jingxuan Yang +5 位作者 Xuefeng Zhang Mengbo Zhao Xiao Du Xiaogang Hao Abuliti Abudula Guoqing Guan 《Chinese Journal of Chemical Engineering》 2025年第9期228-237,共10页
Electrochemically switched ion exchange(ESIX)is an effective technology for extracting high-valueadded ions from dilute solutions.This study focuses on Li^(+)extraction by employing a comprehensive model to analyze in... Electrochemically switched ion exchange(ESIX)is an effective technology for extracting high-valueadded ions from dilute solutions.This study focuses on Li^(+)extraction by employing a comprehensive model to analyze interaction between fluidic dynamics,electric field and ion transport.The model combines Butler-Volmer equation modified by electroactive site concentration,Nernst-Planck equation and Navier-Stokes equation.It is found that the chamber width affects solution phase resistance,thereby altering the pote ntial distribution and influencing the current distribution within the membrane.A narrow chamber increases current density in the solid phase of the membrane,enhancing Li^(+) extraction.The solution flow-field not only enhances convective transport but also increases the current density in the solid phase,promoting Li^(+) extraction.There is a synergistic effect between fluid-flow-field and electric-field for ion separation,which is only significant when the chamber width is greater than 2 mm.The synergistic mechanism differs from that in the capacitive deionization system.Therefore,the performance decline caused by a wide chamber can be compensated for by increasing the fluid-flow rate,utilizing the synergistic effect between the flu id-flow-field and electric-field to optimize the lithium extraction efficiency in the ESIX system. 展开更多
关键词 Electrochemically switched ion exchange Mass transfer and separation Synergistic effect Fluid-flow-field Fluidic dynamics ELECTRIC-FIELD
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Trends in Sequence-Defined Polyelectrolyte Systems:A Perspective
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作者 Qiu-Hui Chang Ruo-Chao Wang +1 位作者 Le-Ying Qing Jian Jiang 《Chinese Journal of Polymer Science》 2025年第1期1-17,I0005,共18页
Polyelectrolytes(PEs)are polymers carrying ionizable groups along the chain backbone and play an important role in life and environmental sciences,industrial applications and other fields.Due to the complicated topolo... Polyelectrolytes(PEs)are polymers carrying ionizable groups along the chain backbone and play an important role in life and environmental sciences,industrial applications and other fields.Due to the complicated topological structure and electrostatic correlations of PEs,PEs exhibit very rich phase behavior and morphologies in both bulk and confined solutions.So far,many theories,simulations and machine learning approaches have been proposed to study the behavior of polyelectrolyte solutions,especially the intrinsic structure-property relationships.In this perspective,from a personal point of view,we present several recent trends in polyelectrolyte solutions.The main themes considered here are accelerated development of sequence-defined polyelectrolyte(SDPE)via artificial intelligence technology,liquid-liquid phase separation in bulk SDPE solutions,adsorption behaviors of SDPE in the vicinity of a single dielectric surface,and surface forces between two charged surfaces mediated by SDPE solutions. 展开更多
关键词 Sequence-defined polyelectrolyte Structure-property relationships Liquid-liquid phase separation Surface and interface
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Factors influencing parental presence in neonatal units:A systematic review
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作者 Anais Marie Bérengère François-Garret +5 位作者 Ambre Filippi Sergio Eleni Dit Trolli Florence Casagrande Jean-Baptiste Lotte Isabelle Guellec Arnaud Fernandez 《World Journal of Clinical Pediatrics》 2025年第4期483-492,共10页
BACKGROUND Parental presence in neonatal units(NUs)is essential for infant development and family well-being.A deeper understanding of the factors influencing parental presence is vital and will contribute to the deve... BACKGROUND Parental presence in neonatal units(NUs)is essential for infant development and family well-being.A deeper understanding of the factors influencing parental presence is vital and will contribute to the development of targeted interventions and policies that enhance parental engagement in neonatal care,thereby improving outcomes for infants and their families.AIM To identify and analyze primary factors influencing parental involvement in their child’s care in a neonatal intensive care unit(NICU).METHODS A literature search was conducted using the PubMed,MEDLINE,and Cochrane Library for systematic reviews databases,with the following search terms:“parental presence neonatology”,“couplet care”,“zero separation neonatal care”,“family integrated care”,“couplet care intervention”,“mother-child separation”,“parents newborn togetherness”,“mother-baby care”,“closeness and separation NICU”,“mother-infant interaction NICU”,“kangaroo care”,“dyad mother-infant”,and“newborn integrated care”.The database search for this literature review began on December 10,2024,with the final search conducted on April 10,2025.RESULTS The literature search yielded 281 articles,out of which 23 were selected for a detailed review.The factors associated with parental presence in NUs were grouped into five main categories:Parents’socio-demographic and cultural traits;the physical layout and care model of the NUs;the quality of parents’relationships with the healthcare staff;their active involvement in neonatal care;and the newborn’s health status.CONCLUSION The identification of factors that affect parental presence in NUs is critical for developing effective strategies aimed at encouraging increased parental involvement and ultimately improving neonatal and family outcomes. 展开更多
关键词 Parental presence Neonatal intensive care unit NEONATOLOGY Couplet care Kangaroo care Family-centered care Parental involvement Infant development Zero separation
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A Novel Feedforward Hybrid Active Noise Control System with Narrowband Frequency Adaptive Estimation and Error Separation
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作者 PANG Mingrui LIU Yifei LIU Jian 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第5期638-647,共10页
The conventional feedforward hybrid active noise control(FFHANC)system combines the advantages of the feedforward narrowband active noise control(FFNANC)system and the feedforward broadband active noise control(FFBANC... The conventional feedforward hybrid active noise control(FFHANC)system combines the advantages of the feedforward narrowband active noise control(FFNANC)system and the feedforward broadband active noise control(FFBANC)system.To enhance its adaptive adjustment capability under frequency mismatch(FM)conditions,this paper introduces a narrowband frequency adaptive estimation module into the conventional FFHANC system.This module integrates an autoregressive(AR)model and a linear cascaded adaptive notch filter(LCANF),enabling accurate reference signal frequency estimation even under significant FM.Furthermore,in order to improve the coherence between narrowband and broadband components in the system’s error signal and its corresponding control filter for the conventional FFHANC system,this paper proposes an algorithm based on autoregressive bandpass filter bank(AR-BPFB)for error separation.Simulation results demonstrate that the proposed FFHANC system maintains robust performance under high FM conditions and effectively suppresses hybrid-band noise.The AR-BPFB algorithm significantly elevates the convergence speed of the FFHANC system. 展开更多
关键词 active noise control feedforward hybrid active noise control(FFHANC)system autoregressive(AR)model linear cascaded adaptive notch filter(LCANF) bandpass filter bank(BPFB) error separation
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Solvent extraction of hafnium from thiocyanic acid medium in DIBK-TBP mixed system 被引量:6
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作者 徐志高 王力军 +3 位作者 吴延科 池汝安 张力 吴明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第7期1760-1765,共6页
A novel process for the separation of hafnium from thiocyanic acid medium using the mixture of diisobutyl ketone(DIBK) and tributyl phosphate(TBP) as the extractant was developed.This extraction process was invest... A novel process for the separation of hafnium from thiocyanic acid medium using the mixture of diisobutyl ketone(DIBK) and tributyl phosphate(TBP) as the extractant was developed.This extraction process was investigated experimentally as a function of the amount of TBP added,acidity,zirconium and hafnium concentrations,salting-out agent,temperature,duration,respectively.The results show that hafnium is enriched in the organic layer and zirconium is in aqueous layer in DIBK-TBP system.Under the optimal technological conditions:TBP addition 20%(v/v),aqueous phase acidity 3.0 mol/L,ammonium sulfate addition 0.8-1.25 mol/L,room temperature and extraction time 10 min,the separation factor of hafnium from zirconium is 9.3. 展开更多
关键词 diisobutyl ketone(DIBK) ZIRCONIUM HAFNIUM EXTRACTION SEPARATION
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MODELING AND NUMERICAL SIMULATION OF ONBOARD MOLECULAR SIEVE OXYGEN GENERATION SYSTEM 被引量:3
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作者 武艳 林贵平 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第1期47-52,共6页
A mathematical model for simulating concentric-bed and other components of molecular sieve oxygen concentrator is established. In the model, the binary Langmuir equilibrium adsorption equation is adopted to describe t... A mathematical model for simulating concentric-bed and other components of molecular sieve oxygen concentrator is established. In the model, the binary Langmuir equilibrium adsorption equation is adopted to describe the adsorption performance of the adsorbent, the linear driving force (LDF) model is used to describe the mass transfer rate, and the thermal effect during adsorption is considered. The finite difference method is used in simulation and comparison. Numerical results have a reasonable agreement with the experimental research. 展开更多
关键词 pressure swing adsorption molecular sieve gas separation onboard oxygen generation system (OBOGS)
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Exchange Bias Effect in Phase Separated La0.33Pr0.34Ca0.33MnO3 Thin Films
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作者 李惠 李林 +2 位作者 成龙 梁海星 曾长淦 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第4期475-478,J0002,共5页
Exchange bias effect is observed in the phase separated La0.33Pr0.34Ca0.33MnO3 thin films. High exchange bias field of about 1 kOe is achieved at 4 K. The exchange bias effect in La0.33Pr0.34Ca0.33MnO3 thin films migh... Exchange bias effect is observed in the phase separated La0.33Pr0.34Ca0.33MnO3 thin films. High exchange bias field of about 1 kOe is achieved at 4 K. The exchange bias effect in La0.33Pr0.34Ca0.33MnO3 thin films might originate from the intrinsic phase separation of the La0.33Pr0.34Ca0.33MnO3 or surface effect. The dependence of exchange bias effect on temperature, cooling field, and thickness is also investigated. This work would open an avenue to the application in the magnetic memory devices based on the phase separated manganites. 展开更多
关键词 Exchange bias Phase separation Pulse laser deposition MANGANITES Training effect
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Structure identification for compound I separated and purified from taxoids-produced endophytic fungi (Alternaria. alternata var. taxi 1011)
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作者 项勇 刘君 +1 位作者 呂安国 崔京霞 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第3期217-220,共4页
Endophytic fungi are widely found in almost all kinds of plants. Many endophytic fungi can produce some physio-logical active compounds, which are same to or analog to those isolated from their hosts. Producing physio... Endophytic fungi are widely found in almost all kinds of plants. Many endophytic fungi can produce some physio-logical active compounds, which are same to or analog to those isolated from their hosts. Producing physiological active com-pounds through microbial fermentation can give a new way to resolve resource limitation and to find out alternative source. Through the methods of organic solvent extraction, thin layer chromatography (TLC) and column chromatography, compound I was isolated, purified from the liquid fermentation metabolites of the taxoids-produced endophytic fungi (Alternaria. alternata var. taxi 1011 Y. Xiang et LU An-guo) that was screened from the bark of Taxus. cuspidata Sieb.et Zucc.. Compound I was identified as one kind of taxoids type III, based on the analyzing results by using the methods of ultraviolet spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR). This study provides a com-pleted method for separation and purification of the endophytic fungi as well as structure identification of its fermentation me-tabolite 展开更多
关键词 Alternaria. Alternata var. taxi 1011 TAXOIDS Separation Purification Structure identification
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强磁场条件下的spatial separated D^-心
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作者 邢雁 王旭 《内蒙古大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第5期520-526,共7页
采用 Mac Donld的对角化法研究了强磁场条件下 D-s 心的束缚态和多电子效应 .发现D-s 心有 L=0 ,-1 ,-2 ,-3 ,-4五个束缚态 ,且随着电子与 D0 心之间距离ξ值的增大 ,其束缚能存在一极大值 .并利用无规相近似讨论了长波极限 D-s 心的多... 采用 Mac Donld的对角化法研究了强磁场条件下 D-s 心的束缚态和多电子效应 .发现D-s 心有 L=0 ,-1 ,-2 ,-3 ,-4五个束缚态 ,且随着电子与 D0 心之间距离ξ值的增大 ,其束缚能存在一极大值 .并利用无规相近似讨论了长波极限 D-s 心的多电子效应 ,发现 D-s 心的本征能量随朗道能级填充因子作周期性振荡 ,且随着温度的降低振荡加剧 ;当填充因子为偶数时 ,其本征能量的绝对值最大 ,说明此时电子气对库仑势的屏蔽效应最弱 . 展开更多
关键词 SPATIAL separated D^-心 强磁场 束缚态 多电子效应 对角化法 量子阱 哈密顿量
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