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The Effect of Educational Intervention regarding Advance Care Planning for Advance Directives
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作者 Yae Takeshita Mika Ikeda +1 位作者 Sayaka Sone Michiko Moriyama 《Health》 2015年第8期934-945,共12页
This study aimed to examine the effects of empowerment and education intervention to promote Advance Care Planning (ACP) for residents in a highly aged and depopulated region. The study utilized a single-group pre- an... This study aimed to examine the effects of empowerment and education intervention to promote Advance Care Planning (ACP) for residents in a highly aged and depopulated region. The study utilized a single-group pre- and post-test design and was conducted in Osakikamijima, Hiroshima, Japan. The researchers and town officials together formed an ACP committee and created an intervention framework. An ACP workshop was held for the participants and a self-administered questionnaire was carried out before, immediately after, and 3 months after the workshop. A total of 125 residents participated in the workshop and 87 of them completed more than 80% of the questionnaire items, whose responses were analyzed as valid responses. The number of participants who completed the AD increased significantly three months after the workshop (p = 0.008). There was a slight increase in the frequency of consultation with the family, but no change was observed in terms of consultation with healthcare providers. The educational intervention in-creased the respondents’ awareness and knowledge of ACP but did not affect the autonomous decision-making process regarding end-of-life care. This strategic process of ACP empowered the residents’ awareness and attitude towards end-of-life care with an increased completion rate of AD. On the other hand, cognitive barriers remained toward communication and decision-making shared with healthcare providers. Insufficient consultation with family members also became evident. Therefore, a new intervention strategy which helps increase communication with healthcare providers needs to be formulated and guidelines for consultation with the family and others need to be prepared. 展开更多
关键词 END-OF-LIFE ADVANCE CARE Planning ADVANCE directives COMMUNITY EMPOWERMENT
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Advance Directives in the Context of Uncertain Prognosis for Residents of Nursing Homes
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作者 Beryl E. Cable-Williams Donna M. Donna M. Wilson Norah Keating 《Open Journal of Nursing》 2014年第4期321-329,共9页
This report documents the findings of a mixed-methods study focused on the advanced directives of 182 residents of three LTC facilities in southern Ontario, Canada. Although almost all had a completed advance directiv... This report documents the findings of a mixed-methods study focused on the advanced directives of 182 residents of three LTC facilities in southern Ontario, Canada. Although almost all had a completed advance directive within 3 months of death, most did not have a palliative designation or directive until a few days before they died. Each facility’s written Progress Notes revealed staff members usually sought additional confirmation of care preferences from residents’ substitute decision-makers within a few days of the death. It was thus common for advance directives to change from a more interventionist approach to the least interventionist approach near death. This change indicates that the meaning and significance of advance care planning and resulting advance directives must be considered in light of the processes and temporal factors involved in their completion and use within this distinct population. The relational nature of advance care planning and concern about ageism as a factor for withholding or withdrawing life support for LTC residents are considered as possible explanatory factors. These findings and their implications are described in relation to end-of-life care policies and practices in LTC facilities. 展开更多
关键词 ADVANCE CARE Planning ADVANCE directives PALLIATIVE CARE Nursing HOMES
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Assessment of a Multimodal Strategy for Information and Collection of Advance Directives in a Comprehensive Cancer Center:Description of the Study Protocol
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作者 Léonor Fasse François Blot 《Psycho-Oncologie》 SCIE 2024年第4期367-375,共9页
Background:Information on the possibility of drawing up Advance Directives(AD)is a necessity,and represents a major medical,ethical,and legal challenge.The difficulties are numerous,both organizational and cultural,an... Background:Information on the possibility of drawing up Advance Directives(AD)is a necessity,and represents a major medical,ethical,and legal challenge.The difficulties are numerous,both organizational and cultural,and this is also true in the context of oncology,where ADs(and more broadly,advanced palliative care)are of critical importance.As an eminently sensitive subject,dealing with ADs(and therefore with end-of-life issues)requires both societal and medical/health-care acculturation.An institutional approach has therefore been developed,to deploy information tools,training professionals,and formalize the collection of AD.Such an approach cannot be implemented without an assessment not only of its objective results but also above all of its psychological effects,on both users(patients,family caregivers)and professionals.Methods:This longitudinal study,based on a mixed-method,interdisciplinary approach,will assess the impact of this information dissemination on AD,in terms of both potential positive and negative effects,using validated measurement methods.Thus,this study follows the 5 criteria of the RE-AIM model,designed to analyze the interest and impact of a device intended for users of the healthcare system;we will use a mixed methodology,relying on both a quantitative component(counting the number of people benefiting from the scheme,and those requesting support in drawing up their DA...,administering questionnaires),as well as a qualitative component(focus groups)which will enable us to study the subjective experiences of users,their relatives and the professionals involved in the scheme.Results:The results of this study will make it possible to determine the effects of this system of assistance in the drafting of ADs,which is currently being promoted by the legislator,but which is struggling to be implemented. 展开更多
关键词 Advance directive CANCER palliative care living wills end of life shared-decision making
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Directives and references in selected coronavirus-motivated internet memes 被引量:1
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作者 Ayo Osisanwo Toluwalope Mary Falade 《Language and Semiotic Studies》 2024年第2期245-266,共22页
The use of directives in communicating the nature of the pandemic and reference to social experiences were promoted using images on social media platforms.The images or memes are used to create awareness and reinforce... The use of directives in communicating the nature of the pandemic and reference to social experiences were promoted using images on social media platforms.The images or memes are used to create awareness and reinforce the criteria for safety during the pandemic.Previous studies on internet memes have concentrated on humor generation,speaker-hearer shared knowledge,neologism,and multimodality among others,with insufficient attention paid to the use of directives and references in such coronavirus-motivated memes.This paper,therefore,examines how directives and references are employed in conveying expected social responsibilities through coronavirus-motivated internet memes in Nigeria and other socio-cultural contexts.For data,one hundred coronavirus-motivated memes were purposively selected from Facebook,and eight representative memes were subjected to pragmatic analysis using aspects of Jacob Mey’s(2001.Pragmatics:An introduction,2nd edn.USA:Blackwell Publishing)pragmatic acts theory to unearth insights from them.The paper observes that the various spheres of life that are relatable to an online audience help to express what the pandemic is about and enhance the meaning of the pandemic with the context of the use of the memes,giving clearer perspectives on the pandemic.Directives and references are useful tools for conveying social responsibilities to online audience. 展开更多
关键词 directives REFERENCES CORONAVIRUS internet memes social responsibilities
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IOTA-Based Authentication for IoT Devices in Satellite Networks
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作者 D.Bernal O.Ledesma +1 位作者 P.Lamo J.Bermejo 《Computers, Materials & Continua》 2026年第1期1885-1923,共39页
This work evaluates an architecture for decentralized authentication of Internet of Things(IoT)devices in Low Earth Orbit(LEO)satellite networks using IOTA Identity technology.To the best of our knowledge,it is the fi... This work evaluates an architecture for decentralized authentication of Internet of Things(IoT)devices in Low Earth Orbit(LEO)satellite networks using IOTA Identity technology.To the best of our knowledge,it is the first proposal to integrate IOTA’s Directed Acyclic Graph(DAG)-based identity framework into satellite IoT environments,enabling lightweight and distributed authentication under intermittent connectivity.The system leverages Decentralized Identifiers(DIDs)and Verifiable Credentials(VCs)over the Tangle,eliminating the need for mining and sequential blocks.An identity management workflow is implemented that supports the creation,validation,deactivation,and reactivation of IoT devices,and is experimentally validated on the Shimmer Testnet.Three metrics are defined and measured:resolution time,deactivation time,and reactivation time.To improve robustness,an algorithmic optimization is introduced that minimizes communication overhead and reduces latency during deactivation.The experimental results are compared with orbital simulations of satellite revisit times to assess operational feasibility.Unlike blockchain-based approaches,which typically suffer from high confirmation delays and scalability constraints,the proposed DAG architecture provides fast,cost-free operations suitable for resource-constrained IoT devices.The results show that authentication can be efficiently performed within satellite connectivity windows,positioning IOTA Identity as a viable solution for secure and scalable IoT authentication in LEO satellite networks. 展开更多
关键词 Satellite IoT decentralized authentication directed acyclic graph IOTA identity verifiable credentials
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Effects of noninvasive brain stimulation on motor functions in animal models of ischemia and trauma in the central nervous system
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作者 Seda Demir Gereon R.Fink +1 位作者 Maria A.Rueger Stefan J.Blaschke 《Neural Regeneration Research》 2026年第4期1264-1276,共13页
Noninvasive brain stimulation techniques offer promising therapeutic and regenerative prospects in neurological diseases by modulating brain activity and improving cognitive and motor functions.Given the paucity of kn... Noninvasive brain stimulation techniques offer promising therapeutic and regenerative prospects in neurological diseases by modulating brain activity and improving cognitive and motor functions.Given the paucity of knowledge about the underlying modes of action and optimal treatment modalities,a thorough translational investigation of noninvasive brain stimulation in preclinical animal models is urgently needed.Thus,we reviewed the current literature on the mechanistic underpinnings of noninvasive brain stimulation in models of central nervous system impairment,with a particular emphasis on traumatic brain injury and stroke.Due to the lack of translational models in most noninvasive brain stimulation techniques proposed,we found this review to the most relevant techniques used in humans,i.e.,transcranial magnetic stimulation and transcranial direct current stimulation.We searched the literature in Pub Med,encompassing the MEDLINE and PMC databases,for studies published between January 1,2020 and September 30,2024.Thirty-five studies were eligible.Transcranial magnetic stimulation and transcranial direct current stimulation demonstrated distinct strengths in augmenting rehabilitation post-stroke and traumatic brain injury,with emerging mechanistic evidence.Overall,we identified neuronal,inflammatory,microvascular,and apoptotic pathways highlighted in the literature.This review also highlights a lack of translational surrogate parameters to bridge the gap between preclinical findings and their clinical translation. 展开更多
关键词 noninvasive brain stimulation preclinical modeling STROKE transcranial direct current stimulation transcranial magnetic stimulation traumatic brain injury
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Discovering API Directives from API Specifications with Text Classification
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作者 Jing-Xuan Zhang Chuan-Qi Tao +1 位作者 Zhi-Qiu Huang Xin Chen 《Journal of Computer Science & Technology》 SCIE EI CSCD 2021年第4期922-943,共22页
Application programming interface(API)libraries are extensively used by developers.To correctly program with APIs and avoid bugs,developers shall pay attention to API directives,which illustrate the constraints of API... Application programming interface(API)libraries are extensively used by developers.To correctly program with APIs and avoid bugs,developers shall pay attention to API directives,which illustrate the constraints of APIs.Unfortunately,API directives usually have diverse morphologies,making it time-consuming and error-prone for developers to discover all the relevant API directives.In this paper,we propose an approach leveraging text classification to discover API directives from API specifications.Specifically,given a set of training sentences in API specifications,our approach first characterizes each sentence by three groups of features.Then,to deal with the unequal distribution between API directives and non-directives,our approach employs an under-sampling strategy to split the imbalanced training set into several subsets and trains several classifiers.Given a new sentence in an API specification,our approach synthesizes the trained classifiers to predict whether it is an API directive.We have evaluated our approach over a publicly available annotated API directive corpus.The experimental results reveal that our approach achieves an F-measure value of up to 82.08%.In addition,our approach statistically outperforms the state-of-the-art approach by up to 29.67%in terms of F-measure. 展开更多
关键词 Application programming interface(API)directive API specification imbalanced learning text classification
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Direct Photolithography of WO_(x) Nanoparticles for High‑Resolution Non‑Emissive Displays 被引量:2
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作者 Chang Gu Guojian Yang +7 位作者 Wenxuan Wang Aiyan Shi Wenjuan Fang Lei Qian Xiaofei Hu Ting Zhang Chaoyu Xiang Yu‑Mo Zhang 《Nano-Micro Letters》 SCIE EI CAS 2025年第3期297-309,共13页
High-resolution non-emissive displays based on electrochromic tungsten oxides(WOx)are crucial for future near-eye virtual/augmented reality interactions,given their impressive attributes such as high environmental sta... High-resolution non-emissive displays based on electrochromic tungsten oxides(WOx)are crucial for future near-eye virtual/augmented reality interactions,given their impressive attributes such as high environmental stability,ideal outdoor readability,and low energy consumption.However,the limited intrinsic structure of inorganic materials has presented a significant challenge in achieving precise patterning/pixelation at the micron scale.Here,we successfully developed the direct photolithography for WOx nanoparticles based on in situ photo-induced ligand exchange.This strategy enabled us to achieve ultra-high resolution efficiently(line width<4μm,the best resolution for reported inorganic electrochromic materials).Additionally,the resulting device exhibited impressive electrochromic performance,such as fast response(<1 s at 0 V),high coloration efficiency(119.5 cm^(2) C^(−1)),good optical modulation(55.9%),and durability(>3600 cycles),as well as promising applications in electronic logos,pixelated displays,flexible electronics,etc.The success and advancements presented here are expected to inspire and accelerate research and development(R&D)in high-resolution non-emissive displays and other ultra-fine micro-electronics. 展开更多
关键词 Electrochromic Direct photolithography WOx nanoparticles In situ photo-induced ligand exchange High-resolution displays
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Assessment of seismic intensity and seismic performance of buildings in the M7.9 Myanmar earthquake 被引量:3
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作者 Sun Baitao Yan Jiaqi +2 位作者 Yang Yongqiang Chen Xiangzhao Sun Menghan 《Earthquake Engineering and Engineering Vibration》 2025年第3期641-652,共12页
Dispatched by the Chinese government,a multidisciplinary team of 30 researchers collaborated with a team from Myanmar to conduct a 14-day on-site investigation.The work encompassed seismic intensity assessments,field ... Dispatched by the Chinese government,a multidisciplinary team of 30 researchers collaborated with a team from Myanmar to conduct a 14-day on-site investigation.The work encompassed seismic intensity assessments,field surveys,and loss evaluations.The paper focuses on the intensity distribution and structural damage characteristics of the 2025 M7.9 Myanmar earthquake,yielding the following key findings.(1)The seismogenic fault rupture propagated in a nearly N-S direction,with a surface rupture length of approximately 450 km.The seismic impact zone exhibited an elongated N-S distribution and a shorter E-W span,distributed like a belt around the seismogenic fault.(2)Within the seismic impact zones,existing buildings comprised five primary structural types,with timber(bamboo)structures constituting the largest proportion(≈80%in rural areas,≈50%in urban areas).The relatively low disaster losses and casualties were primarily attributable to the good seismic performance and low damage ratio of timber(bamboo)structures across varying intensity zones.(3)An anomalous zone of intensityⅨwas located at the boundary between intensityⅥandⅦregions in Nay Pyi Taw.Here,ridge topography combined with soft soil layers significantly amplified ground motion,exacerbating structural damage.(4)Directional effects of ground motion were observed,with the structural damage phenomena and peak ground acceleration(PGA)values in the N-S direction exceeding those in the E-W direction.This validates that the maximum PGA distribution of strike-slip fault earthquakes aligns with the fault strike.The research is expected to provide technical support for post-disaster reconstruction planning,site selection,and disaster mitigation strategies in Myanmar. 展开更多
关键词 M7.9 Myanmar earthquake seismic intensity timber(bamboo)structure directional effects of ground motion strike-slip fault
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Degradation mechanism,direct regeneration and upcycling of ternary cathode material for retired lithium-ion power batteries 被引量:2
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作者 Juan Wang Dongqi Li +6 位作者 Weihao Zeng Xingye Chen Yixin Zhang Shaojie Zhang Zhongpeng Li Changhao Li Shichun Mu 《Journal of Energy Chemistry》 2025年第3期534-554,共21页
With the approaching of large-scale retirement of power lithium-ion batteries(LIBs),their urgent handling is required for environmental protection and resource reutilization.However,at present,substantial spent power ... With the approaching of large-scale retirement of power lithium-ion batteries(LIBs),their urgent handling is required for environmental protection and resource reutilization.However,at present,substantial spent power batteries,especially for those high recovery value cathode materials,have not been greenly,sustainably,and efficiently recycled.Compared to the traditional recovery method for cathode materials with high energy consumption and severe secondary pollution,the direct repair regeneration,as a new type of short-process and efficient treatment methods,has attracted widespread attention.However,it still faces challenges in homogenization repair,electrochemical performance decline,and scaling-up production.To promote the direct regeneration technology development of failed NCM materials,herein we deeply discuss the failure mechanism of nickel-cobalt-manganese(NCM)ternary cathode materials,including element loss,Li/Ni mixing,phase transformation,structural defects,oxygen release,and surface degradation and reconstruction.Based on this,the detailed analysis and summary of the direct regeneration method embracing solid-phase sintering,eutectic salt assistance,solvothermal synthesis,sol-gel process,spray drying,and redox mediation are provided.Further,the upcycling strategy for regeneration materials,such as single-crystallization and high-nickelization,structural regulation,ion doping,and surface engineering,are discussed in deep.Finally,the challenges faced by the direct regeneration and corresponding countermeasures are pointed out.Undoubtedly,this review provides valuable guidance for the efficient and high-value recovery of failed cathode materials. 展开更多
关键词 Spent NCM materials Retired lithium-ion power battery Degradation mechanism Direct regeneration Upcycling strategy
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Challenges and development direction of deep fragmented soft coalbed methane in China 被引量:2
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作者 Yiyu Lu Guilin Zhao +7 位作者 Zhaolong Ge Yunzhong Jia Jiren Tang Tianyi Gong Shan Huang Zhongtan Li Wenyu Fu Jianyu Mi 《Earth Energy Science》 2025年第1期38-64,共27页
Developing deep fragmented soft coalbed methane(CBM)can significantly enhance domestic natural gas supplies,reduce reliance on imported energy,and bolster national energy security.This manuscript provides a comprehens... Developing deep fragmented soft coalbed methane(CBM)can significantly enhance domestic natural gas supplies,reduce reliance on imported energy,and bolster national energy security.This manuscript provides a comprehensive review of commonly employed coalbed methane extraction technologies.It then delves into several critical issues in the current stage of CBM exploration and development in China,including the compatibility of existing technologies with CBM reservoirs,the characteristics and occurrence states of CBM reservoirs,critical desorption pressure,and gas generation mechanisms.Our research indicates that current CBM exploration and development technologies in China have reached an internationally advanced level,yet the industry is facing unprecedented challenges.Despite progress in low-permeability,high-value coal seams,significant breakthroughs have not been achieved in exploring other types of coal seams.For different coal reservoirs,integrated extraction technologies have been developed,such as surface pre-depressurisation and segmented hydraulic fracturing of coal seam roof strata.Additionally,techniques like large-scale volume fracturing in horizontal wells have been established,significantly enhancing reservoir stimulation effects and coalbed methane recovery rates.However,all of these technologies are fundamentally based on permeation.These technologies lack direct methods aimed at enhancing the diffusion rate of CBM,thereby failing to fully reflect the unique characteristics of CBM.Current CBM exploration and development theories and technologies are not universally applicable to all coal seams.They do not adequately account for the predominantly adsorbed state of CBM,and the complex and variable gas generation mechanisms further constrain CBM development in China.Finally,continuous exploration of new deep CBM exploration technologies is necessary.Integrating more effective reservoir stimulation technologies is essential to enhance technical adaptability concerning CBM reservoir characteristics,gas occurrence states,and gas generation mechanisms,ultimately achieving efficient CBM development.We conclude that while China possesses a substantial foundation of deep fractured CBM resources,industry development is constrained and requires continuous exploration of new CBM exploration and development technologies to utilize these resources effectively. 展开更多
关键词 Deep coalbed methane Exploration and development technology Reservoir characteristics Critical desorption pressure Gas production mechanism Development direction
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Porous sorbents for direct capture of carbon dioxide from ambient air 被引量:1
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作者 Yuchen Zhang Lifeng Ding +3 位作者 Zhenghe Xie Xin Zhang Xiaofeng Sui Jian-Rong Li 《Chinese Chemical Letters》 2025年第3期125-133,共9页
Large-scale deployment of carbon dioxide(CO_(2))removal technology is an essential step to cope with global warming and achieve carbon neutrality.Direct air capture(DAC)has recently received increasing attention given... Large-scale deployment of carbon dioxide(CO_(2))removal technology is an essential step to cope with global warming and achieve carbon neutrality.Direct air capture(DAC)has recently received increasing attention given the high flexibility to remove CO_(2)from discrete sources.Porous materials with adjustable pore characteristics are promising sorbents with low or no latent heat of vaporization.This review article has summarized the recent development of porous sorbents for DAC,with a focus of pore engineering strategy and adsorption mechanism.Physisorbents such as zeolites,porous carbons,metal-organic frameworks(MOFs),and amine-modified chemisorbents have been discussed and their challenges in practical application have been analyzed.At last,future directions have been proposed,and it is expected to inspire collaborations from chemistry,environment,material science and engineering communities. 展开更多
关键词 Direct air capture Carbon neutrality Porous materials PHYSISORPTION CHEMISORPTION
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Facile regeneration of spent lithium-ion battery cathode materials via tunable oxidization and reduction strategy 被引量:1
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作者 Xue-hu ZHONG Wen-qing QIN +1 位作者 Jiang ZHOU Jun-wei HAN 《Transactions of Nonferrous Metals Society of China》 2025年第2期653-668,共16页
A tunable oxidization and reduction strategy was proposed to directly regenerate spent LiFePO_(4)/C cathode materials by oxidizing excessive carbon powders with the addition of FePO_(4).Experimental results indicate t... A tunable oxidization and reduction strategy was proposed to directly regenerate spent LiFePO_(4)/C cathode materials by oxidizing excessive carbon powders with the addition of FePO_(4).Experimental results indicate that spent LiFePO_(4)/C cathode materials with good performance can be regenerated by roasting at 650℃ for 11 h with the addition ofLi_(2)CO_(3),FePO_(4),V_(2)O_(5),and glucose.V_(2)O_(5) is added to improve the cycle performance of regenerated cathode materials.Glucose is used to revitalize the carbon layers on the surface of spent LiFePO_(4)/C particles for improving their conductivity.The regenerated V-doped LiFePO_(4)/C shows an excellent electrochemical performance with the discharge specific capacity of 161.36 mA·h/g at 0.2C,under which the capacity retention is 97.85%after 100 cycles. 展开更多
关键词 spent lithium-ion batteries direct regeneration cathode materials ROASTING circular economy
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Smart Cellulose‑Based Janus Fabrics with Switchable Liquid Transportation for Personal Moisture and Thermal Management
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作者 Jianfeng Xi Yanling Lou +5 位作者 Liucheng Meng Chao Deng Youlu Chu Zhaoyang Xu Huining Xiao Weibing Wu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期333-347,共15页
The Janus fabrics designed for personal moisture/thermal regulation have garnered significant attention for their potential to enhance human comfort.However,the development of smart and dynamic fabrics capable of mana... The Janus fabrics designed for personal moisture/thermal regulation have garnered significant attention for their potential to enhance human comfort.However,the development of smart and dynamic fabrics capable of managing personal moisture/thermal comfort in response to changing external environments remains a challenge.Herein,a smart cellulose-based Janus fabric was designed to dynamically manage personal moisture/heat.The cotton fabric was grafted with N-isopropylacrylamide to construct a temperature-stimulated transport channel.Subsequently,hydrophobic ethyl cellulose and hydrophilic cellulose nanofiber were sprayed on the bottom and top sides of the fabric to obtain wettability gradient.The fabric exhibits anti-gravity directional liquid transportation from hydrophobic side to hydrophilic side,and can dynamically and continuously control the transportation time in a wide range of 3–66 s as the temperature increases from 10 to 40℃.This smart fabric can quickly dissipate heat at high temperatures,while at low temperatures,it can slow down the heat dissipation rate and prevent the human from becoming too cold.In addition,the fabric has UV shielding and photodynamic antibacterial properties through depositing graphitic carbon nitride nanosheets on the hydrophilic side.This smart fabric offers an innovative approach to maximizing personal comfort in environments with significant temperature variations. 展开更多
关键词 Directional water transport Cotton fabric Anti-gravity directional liquid transportation Janus wettability
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Heterogeneous interfaces of aluminum bronze/Inconel 718 dissimilar alloys under different wire arc directed energy deposition sequences 被引量:1
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作者 Tianxing Chang Xuewei Fang +4 位作者 You Zhou Hongkai Zhang Naiyuan Xi Shahid Ghafoor Ke Huang 《International Journal of Extreme Manufacturing》 2025年第1期368-381,共14页
The layer-by-layer deposition strategy of additive manufacturing makes it ideal to fabricate dissimilar alloy components with varying functionality,which has promising application potential in a large number of indust... The layer-by-layer deposition strategy of additive manufacturing makes it ideal to fabricate dissimilar alloy components with varying functionality,which has promising application potential in a large number of industrial areas.In this study,two components composed of ERCuAl-A2 aluminum bronze(CuAl9)and Inconel 718 nickel-based superalloy were fabricated with different deposition orders by wire-arc directed energy deposition.Subject to changes in heat input and thermophysical properties of the substrate,the transition region of the deposited Cu-Ni component with the bottom half of CuAl9 and the top half of Inconel 718 is narrow and serrated.This region features a laminated intermetallic compound layer due to the convection and rapid cooling in the molten pool.In contrast,the Ni-Cu component deposited in the opposite order exhibits a 2 mm gradient transition zone.Within this region,a large number of diverse precipitates were found as well as regional variations in grain size due to the multi-layer partial remelting.Both two components show strong bonds and their tensile specimens tested along the vertical direction always fracture at the softer CuAl9 side.Excellent tensile properties along the horizontal direction were obtained for Cu-Ni(Ultimate tensile strength:573 MPa,yield stress:302 MPa,elongation:22%),while those of Ni-Cu are much lower due to the existence of the solidification cracks in the transition zone.The results from this study provide a reference for the additive manufacturing of Cu/Ni dissimilar alloy components,as well as their microstructure and mechanical properties control. 展开更多
关键词 wire-arc directed energy deposition dissimilar alloys microstructure aluminum bronze nickel-based super-alloy
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Direct regeneration of spent LiFePO_(4)cathode material via a simple solid-phase method 被引量:1
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作者 Hao Sun Xiaoxue Li +5 位作者 Baoyu Wu Kai Zhu Yinyi Gao Tianzeng Bao Hongbin Wu Dianxue Cao 《Chinese Chemical Letters》 2025年第6期745-751,共7页
For realizing the goals of“carbon peak”and“carbon neutrality”,lithium-ion batteries(LIB)with LiFePO_(4)as the cathode material have been widely applied.However,this has also led to a large number of spent lithium-... For realizing the goals of“carbon peak”and“carbon neutrality”,lithium-ion batteries(LIB)with LiFePO_(4)as the cathode material have been widely applied.However,this has also led to a large number of spent lithium-ion batteries,and the safe disposal of spent lithium-ion batteries is an urgent issue.Currently,the main reason for the capacity decay of LiFePO_(4)materials is the Li deficiency and the formation of the Fe^(3+)phase.In order to address this issue,we performed high-temperature calcination of the discarded lithium iron phosphate cathode material in a carbon dioxide environment to reduce or partially remove the carbon coating on its surface.Subsequently,mechanical grinding was conducted to ensure thorough mixing of the lithium source with the discarded lithium iron phosphate.The reaction between CO_(2)and the carbon coating produced a reducing atmosphere,reducing Fe^(3+)to Fe^(2+)and thereby reducing the content of Fe^(3+).The Fe^(3+)content in the repaired LiFePO_(4)material is reduced.The crystal structure of spent LiFePO_(4)cathode materials was repaired more completely compare with the traditional pretreatment method,and the repaired LiFePO_(4)material shows good electrochemical performance and cycling stability.Under 0.1 C conditions,the initial capacity can reach 149.1 m Ah/g.It can be reintroduced for commercial use. 展开更多
关键词 Spent LiFePO_(4) Carbon dioxide Carbon coating Lithium-iron antiphase defects Direct regeneration
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Non-explosive directional fracturing blasting using coal-based solid waste expanding agent 被引量:1
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作者 Quan Zhang Manchao He +7 位作者 Jiong Wang Shan Guo Chao Wang Chenjie Hong Kai Chen Rongzhou Yang Xuepeng Zhang Jianwei Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第6期3691-3710,共20页
Aiming at mitigating the high risks associated with conventional explosive blasting,this study developed a safe directional fracturing technique,i.e.instantaneous expansion with a single fracture(IESF),using a coal-ba... Aiming at mitigating the high risks associated with conventional explosive blasting,this study developed a safe directional fracturing technique,i.e.instantaneous expansion with a single fracture(IESF),using a coal-based solid waste expanding agent.First,the mechanism of directional fracturing blasting by the IESF was analyzed,and the criterion of directional crack initiation was established.On this basis,laboratory experiments and numerical simulations were conducted to systematically evaluate the directional fracturing blasting performance of the IESF.The results indicate that the IESF presents an excellent directional fracturing effect,with average surface undulation differences ranging from 8.1 mm to 22.7 mm on the fracture surfaces.Moreover,during concrete fracturing tests,the stresses and strains in the fracturing direction are measured to be 2.16-3.71 times and 8 times larger than those in the nonfracturing direction,respectively.Finally,the IESF technique was implemented for no-pillar mining with gob-side entry retaining through roof cutting and pressure relief in an underground coal mine.The IESF technique effectively created directional cracks in the roof without causing severe roadway deformation,achieving an average cutting rate and maximum roadway deformation of 94%and 197 mm,respectively.These on-site test results verified its excellent directional rock fracturing performance.The IESF technique,which is safe,efficient,and green,has considerable application prospects in the field of rock mechanics and engineering. 展开更多
关键词 Coal-based solid waste expanding agent Directional fracturing blasting Non-explosive Crack initiation Stress-strain-damage evolution
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Fingerprint-enhanced hierarchical molecular graph neural networks for property prediction 被引量:1
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作者 Shuo Liu Mengyun Chen +1 位作者 Xiaojun Yao Huanxiang Liu 《Journal of Pharmaceutical Analysis》 2025年第6期1311-1320,共10页
Accurate prediction of molecular properties is crucial for selecting compounds with ideal properties and reducing the costs and risks of trials.Traditional methods based on manually crafted features and graph-based me... Accurate prediction of molecular properties is crucial for selecting compounds with ideal properties and reducing the costs and risks of trials.Traditional methods based on manually crafted features and graph-based methods have shown promising results in molecular property prediction.However,traditional methods rely on expert knowledge and often fail to capture the complex structures and interactions within molecules.Similarly,graph-based methods typically overlook the chemical structure and function hidden in molecular motifs and struggle to effectively integrate global and local molecular information.To address these limitations,we propose a novel fingerprint-enhanced hierarchical graph neural network(FH-GNN)for molecular property prediction that simultaneously learns information from hierarchical molecular graphs and fingerprints.The FH-GNN captures diverse hierarchical chemical information by applying directed message-passing neural networks(D-MPNN)on a hierarchical molecular graph that integrates atomic-level,motif-level,and graph-level information along with their relationships.Addi-tionally,we used an adaptive attention mechanism to balance the importance of hierarchical graphs and fingerprint features,creating a comprehensive molecular embedding that integrated hierarchical mo-lecular structures with domain knowledge.Experiments on eight benchmark datasets from MoleculeNet showed that FH-GNN outperformed the baseline models in both classification and regression tasks for molecular property prediction,validating its capability to comprehensively capture molecular informa-tion.By integrating molecular structure and chemical knowledge,FH-GNN provides a powerful tool for the accurate prediction of molecular properties and aids in the discovery of potential drug candidates. 展开更多
关键词 Deep learning Hierarchical molecular graph Molecular fingerprint Molecular property prediction Directed message-passing neural network
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Microstructure evolution of laser directed energy deposition process prepared CNTs/WE43 composites during solution and aging treatment 被引量:1
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作者 Lyuyuan Wang Zhaodian Wang +3 位作者 Lei Zhao Yuan Chen Yangfan Fu Dongsheng Wu 《Journal of Magnesium and Alloys》 2025年第7期3357-3372,共16页
Solution and aging treatment were conducted on the laser directed energy deposition(LDED)-prepared carbon nanotubes(CNTs)-reinforced WE43(CNTs/WE43)layers to optimize their microstructure and surface properties in thi... Solution and aging treatment were conducted on the laser directed energy deposition(LDED)-prepared carbon nanotubes(CNTs)-reinforced WE43(CNTs/WE43)layers to optimize their microstructure and surface properties in this study.The microstructure of the WE43 and CNTs/WE43 layers was systematically compared.The dissolution of divorced eutectics at the grain boundaries was retarded by CNTs during solution treatment.The spot segregation composed of Mg_(24)Y_(5),CNTs,and Zr cores in the solution treated CNTs/WE43 layer presented a slight decreasing in Y content.The grain growth of both types of layers underwent three stages:slow,rapid,and steady-state.The significant inhibitory effect of CNTs on the grain growth of the LDED WE43 matrix was more pronounced than the promoting effect of temperature,resulting in a 47%increase at 510℃ and a 35%increase at 540℃ in the grain growth exponent compared to the WE43 layers at 510℃.During the subsequent aging treatment at 225℃,the precipitation sequences from plate-shaped β″to plate-shaped and globular β′ were observed in both types of layers.CNTs can facilitate an increase in the nucleation rate of precipitates,but without accelerating precipitation hardening rate.The long and short diameters of the precipitates in peak-aged state were decreased by 48.5%and 43.1%by addition of CNTs,respectively.The wear resistance of both the WE43 and CNTs/WE43 layers can be significantly enhanced through solution and aging treatment.The enhancement in wear resistance for the CNTs/WE43 layers is considerably greater than that of the WE43 layers. 展开更多
关键词 Laser directed energy deposition Cnts-reinforced we43 composite Heat treatment Microstructure evolution
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Improving DOA estimation of GNSS interference through sparse non-uniform array reconfiguration 被引量:1
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作者 Rongling LANG Hao XU +3 位作者 Fei GAO Zewen TANG Zhipeng WANG Amir HUSSAIN 《Chinese Journal of Aeronautics》 2025年第8期104-118,共15页
Interference significantly impacts the performance of the Global Navigation Satellite Systems(GNSS),highlighting the need for advanced interference localization technology to bolster anti-interference and defense capa... Interference significantly impacts the performance of the Global Navigation Satellite Systems(GNSS),highlighting the need for advanced interference localization technology to bolster anti-interference and defense capabilities.The Uniform Circular Array(UCA)enables concurrent estimation of the Direction of Arrival(DOA)in both azimuth and elevation.Given the paramount importance of stability and real-time performance in interference localization,this work proposes an innovative approach to reduce the complexity and increase the robustness of the DOA estimation.The proposed method reduces computational complexity by selecting a reduced number of array elements to reconstruct a non-uniform sparse array from a UCA.To ensure DOA estimation accuracy,minimizing the Cramér-Rao Bound(CRB)is the objective,and the Spatial Correlation Coefficient(SCC)is incorporated as a constraint to mitigate side-lobe.The optimization model is a quadratic fractional model,which is solved by Semi-Definite Relaxation(SDR).When the array has perturbations,the mathematical expressions for CRB and SCC are re-derived to enhance the robustness of the reconstructed array.Simulation and hardware experiments validate the effectiveness of the proposed method in estimating interference DOA,showing high robustness and reductions in hardware and computational costs associated with DOA estimation. 展开更多
关键词 GNSS interference location Direction of arrival estimation Adaptive reconfigurable array Cramér-Raobound Quadratic fractional programming
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