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Mothers’challenges and experiences of children with cerebral palsy:a qualitative meta-synthesis
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作者 Meng-Yun Peng Yi-Fu Lu 《Frontiers of Nursing》 2024年第2期169-179,共11页
Objective:To examine what challenges and experiences a mother faces in caring for children with cerebral palsy(CP).As the main caregiver of children with CP,mothers are under multiple pressures.Even though mothers’ch... Objective:To examine what challenges and experiences a mother faces in caring for children with cerebral palsy(CP).As the main caregiver of children with CP,mothers are under multiple pressures.Even though mothers’challenges and experiences of children with CP will affect their quality of life and the rehabilitation of the children,little is known about their challenges and experiences during the whole care.Methods:A qualitative meta-synthesis was conducted to extract and analyze qualitative research from the PubMed,CINAHL,PsycINFO,Web of Science,Ovid and MEDLINE databases.Thirteen articles were selected and analyzed using thematic syntheses.Results:From 2522 screened abstracts,84 texts were reviewed,and 13 studies met the inclusion criteria.Mothers’challenges and experiences of children with CP include 4 themes,both positive and negative.Conclusions:The mothers of children with CP suffer from physical burden,as well as psychological pressure,in the care experience;social and healthcare support are their main challenges.Interventions to help them face the difficulties and adapt to the role of caregivers as soon as possible should target multiple aspects in order to maximize effectiveness,to promote the healthy growth of children with CP. 展开更多
关键词 CHALLENGES children with cerebral palsy EXPERIENCE meta-synthesis mothers
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Dendritic spine degeneration:a primary mechanism in the aging process
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作者 Gonzalo Flores Leonardo Aguilar-Hernández +3 位作者 Fernado García-Dolores Humberto Nicolini Andrea Judith Vázquez-Hernández Hiram Tendilla-Beltrán 《Neural Regeneration Research》 SCIE CAS 2025年第6期1696-1698,共3页
Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a w... Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(Mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(Mayer et al., 2022;AguilarHernández et al., 2023). 展开更多
关键词 AGING process STRESS
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An Unprecedented Efficiency with Approaching 21%Enabled by Additive‑Assisted Layer‑by‑Layer Processing in Organic Solar Cells
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作者 Shuai Xu Youdi Zhang +6 位作者 Yanna Sun Pei Cheng Zhaoyang Yao Ning Li Long Ye Lijian Zuo Ke Gao 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期372-375,共4页
Recently published in Joule,Feng Liu and colleagues from Shanghai Jiaotong University reported a record-breaking 20.8%power conversion efficiency in organic solar cells(OSCs)with an interpenetrating fibril network act... Recently published in Joule,Feng Liu and colleagues from Shanghai Jiaotong University reported a record-breaking 20.8%power conversion efficiency in organic solar cells(OSCs)with an interpenetrating fibril network active layer morphology,featuring a bulk p-in structure and proper vertical segregation achieved through additive-assisted layer-by-layer deposition.This optimized hierarchical gradient fibrillar morphology and optical management synergistically facilitates exciton diffusion,reduces recombination losses,and enhances light capture capability.This approach not only offers a solution to achieving high-efficiency devices but also demonstrates the potential for commercial applications of OSCs. 展开更多
关键词 Organic solar cells Additive-assisted layer-by-layer processing Three-dimensional fibril morphology Bulk p-i-n structure Optical management
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Process Simulate软件在自动化生产线安装调试课程中的应用
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作者 骆峰 杨帆 +1 位作者 胡菡 李智 《工业控制计算机》 2024年第12期37-38,41,共3页
针对自动化生产线安装调试课程的实践教学难题提出了使用仿真软件进行虚拟装调的方案。介绍了如何使用Process Simulate软件对自动化生产线进行虚拟装调。实践证明,使用Process Simulate软件能够有效提高自动化生产线安装调试课程的实... 针对自动化生产线安装调试课程的实践教学难题提出了使用仿真软件进行虚拟装调的方案。介绍了如何使用Process Simulate软件对自动化生产线进行虚拟装调。实践证明,使用Process Simulate软件能够有效提高自动化生产线安装调试课程的实践教学效果。 展开更多
关键词 process Simulate软件 自动化生产线 虚拟装调
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基于Arduino与Processing的心率检测计设计研究 被引量:1
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作者 臧红波 华拓 管志岳 《家电维修》 2024年第3期74-76,共3页
随着社会经济的高速发展,人们的物质生活也有了极大的提高,但同时也伴随着各种疾病的到来,身体健康已经成为人们普遍关注的焦点,因此,心率检测仪、血压计、血糖仪等各种家用医疗监测仪器已经逐渐融入日常生活。心脏病是人们难以预防的... 随着社会经济的高速发展,人们的物质生活也有了极大的提高,但同时也伴随着各种疾病的到来,身体健康已经成为人们普遍关注的焦点,因此,心率检测仪、血压计、血糖仪等各种家用医疗监测仪器已经逐渐融入日常生活。心脏病是人们难以预防的突发致命疾病之一,本文介绍的是一款基于Arduino【是基于易用硬件和软件的原型开源平台,包由可编程的电路板(简称微控制器),以及集成开发环境(称为Arduino IDE)的现成软件组成】Processing(开源编程语言,包括编辑器、编译器、展示器)的简易心率检测计系统,其功能实用、操作简单,可以测量心率,当超出正常心率范围时及时预警,是一款便携的实时心率测试仪。 展开更多
关键词 Arduino processing 心率检测计 设计研究
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Effectiveness of non-pyrimethamine-based regimens for toxoplasma encephalitis:A systematic and meta-synthesis study
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作者 David Susanto Arthur H.P.Mawuntu +1 位作者 Finny Warouw Windy M.V.Wariki 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2022年第3期106-113,共8页
Objective:To examine the differences in effectiveness and side effects between pyrimethamine-based and non-pyrimethamine-based regimens for toxoplasma encephalitis since the availability of pyrimethamine in Indonesia ... Objective:To examine the differences in effectiveness and side effects between pyrimethamine-based and non-pyrimethamine-based regimens for toxoplasma encephalitis since the availability of pyrimethamine in Indonesia is currently limited due to its withdrawal from the market.Methods:A systematic review and meta-synthesis study that was carried out by following a protocol guided by the Preffered Reporting Items for Systematic Review and Meta-analysis(PRISMA).Effectiveness measures included clinical improvement,mortality,and radiological improvement.We evaluated selected articles narratively because of the limitations of homogeneity.The risk of bias in RCTs was assessed using the Cochrane Risk of Bias tool for RCT(ROB 2.0)and cohort studies were assessed using the Risk of Bias In Non-Randomized Studies of Interventions(ROBINS-1)tool.Research quality was assessed using the GradePro software.Results:We included two retrospective cohort studies and one RCT.Narrative outcome assessment in these three studies did not show significant difference in effectiveness between pyrimethamine-based and non-pyrimethamine-based regimens for toxoplasma encephalitis treatment.However,drug side effects were consistently higher in the pyrimethamine-based regimen.Conclusions:This study has a high risk of bias.The quality of the research also has a low recommendation value.However,the results may be considered for application if a standard regimen is not available. 展开更多
关键词 Toxoplasma encephalitis Alternative treatment Without pyrimethamine Systematic review meta-synthesis
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Study on complexity of Sutong Bridge's objectives system and its meta-synthesis management
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作者 Fa Yueping Li Zhen 《Engineering Sciences》 EI 2009年第1期93-100,F0003,共9页
Objectives define the boundaries of complex engineering system.It is a hard work to identify the specific objectives of a complex engineering system.The objectives system development needs a complicated process,from n... Objectives define the boundaries of complex engineering system.It is a hard work to identify the specific objectives of a complex engineering system.The objectives system development needs a complicated process,from nix to prototype,and to final definition.The total process will cover the following course:from chaos to well-ordered;from qualitativeness to combination of quantitativeness and qualitativenss,then from qualitativeness to quantitativeness(a recurrent process),expert experience and theoretical science,rationality and sensibility,synthesis analysis and meta-synthesis,routinization and non-routinization.Such process is explicit in phase development yet overlapped;mutually confined yet mutually independent;permeated conflicts yet pregnant in harmony.This article explores the complexity of Sutong Bridge's objectives development and the process of meta-synthesis in the Sutong Bridge engineering. 展开更多
关键词 objectives system COMPLEXITY meta-synthesis Sutong Bridge
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Nursing students’ experiences of caring for dying patients and their families: a systematic review and meta-synthesis
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作者 Yan Wang 《Frontiers of Nursing》 CAS 2019年第4期261-271,共11页
Objective: Nurses play important roles in caring for dying patients and their families. Difficulties students confronted when facing dying patients challenge the quality of nursing education. A better understanding of... Objective: Nurses play important roles in caring for dying patients and their families. Difficulties students confronted when facing dying patients challenge the quality of nursing education. A better understanding of students' experiences would enhance teachers' ability in helping students. This study aims to describe available evidence about nursing students' experiences when caring for dying patients and their families.Methods: A review of qualitative studies published between 2005 and 2017 was undertaken using the following databases: MEDLINE, CINAHL, ProQuest Central, ScienceDirect, and CNKI. The keywords included were nursing students, experience, care, end-of-life, and dying. Qualitative Assessment and Review Instrument was used to assess the quality of the studies by two independent reviewers. The data from the studies were analyzed by meta-synthesis.Results: Eighteen English and two Chinese studies were selected in this review. Four themes were emerged:(1) Students with dying patients: students did not have enough ability in symptoms control, comfort supply, and therapeutic communication for dying patients.(2) Students with the patients' families: students advocated more caring for patients' families.(3) Students with the surroundings: professional medical staffs, especially the nursing preceptors, were key roles in constructing a supporting system for students.(4) Students with themselves: nursing students underwent various negative feelings and adopted both negative and positive strategies to cope with such feelings;students experienced professional and personal development during the caring for dying patients.Conclusions: Nursing students' abilities in terminal symptom control, comfort supply, and therapeutic communication should be improved by more theoretic learning and simulation practice. The nursing preceptors were key roles in constructing a supporting system for students and helping them to control the negative emotions when facing dying patients. 展开更多
关键词 experiences caring for dying patients nursing student qualitative studies meta-synthesis
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Psychological experience of infected individuals during the pandemic: A qualitative meta-synthesis
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作者 Yao BIAN Haobin YUAN Wipada KUNAVIKTIKUL 《Journal of Integrative Nursing》 2022年第2期83-90,共8页
The purpose of this review is to integrate the psychological experience of infected individuals during the pandemic.The spread of the pandemic has led to psychological and emotional impacts on patients.A qualitative s... The purpose of this review is to integrate the psychological experience of infected individuals during the pandemic.The spread of the pandemic has led to psychological and emotional impacts on patients.A qualitative synthesis is needed to identify,appraise,and integrate the available qualitative findings to provide an evidence for the development of interventions.A meta-aggregation approach was used to analyze studies published in English from January 2020 to August 2021.The JBI Qualitative Assessment and Review Instrument was used to assess the methodological quality of included studies.The ConQual system was used to establish the dependability and credibility in the synthesized findings.Six phenomenological studies and one narrative inquiry with an overall quality score of 70%-100% were included.The research findings from 87 participants in eligible studies were aggregated into three categories based on similarity of meaning.Two synthesized findings were generated and rated as moderate based on the ConQual score.The synthesized findings suggested that participants had psychological distress such as fear,anxiety,loneliness,and uncertainty,but they accepted the fact of being infected and tried to adjust themselves using some self-coping strategies,such as diverting attention from disease,seeking help from professional counselors,relying on religious beliefs,and participating in religious activities.They would like to learn more about infections and diseases and needed more informational support from health-care professionals.They were looking forward to recovery from the disease. 展开更多
关键词 COVID-19 meta-synthesis PANDEMIC psychological experience qualitative study
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Constraints on Characteristics and Distribution of Gas Hydrate and Free Gas Using Broad-Band Processing of Three-Dimensional Seismic Data 被引量:2
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作者 WANG Xiujuan ZHOU Jilin +7 位作者 LI Sanzhong LI Lixia LI Jie LI Yuanping WANG Linfei SU Pibo JIN Jiapeng GONG Zhi 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第5期1233-1247,共15页
Gas hydrate drilling expeditions in the Pearl River Mouth Basin,South China Sea,have identified concentrated gas hydrates with variable thickness.Moreover,free gas and the coexistence of gas hydrate and free gas have ... Gas hydrate drilling expeditions in the Pearl River Mouth Basin,South China Sea,have identified concentrated gas hydrates with variable thickness.Moreover,free gas and the coexistence of gas hydrate and free gas have been confirmed by logging,coring,and production tests in the foraminifera-rich silty sediments with complex bottom-simulating reflectors(BSRs).The broad-band processing is conducted on conventional three-dimensional(3D)seismic data to improve the image and detection accuracy of gas hydratebearing layers and delineate the saturation and thickness of gas hydrate-and free gas-bearing sediments.Several geophysical attributes extracted along the base of the gas hydrate stability zone are used to demonstrate the variable distribution and the controlling factors for the differential enrichment of gas hydrate.The inverted gas hydrate saturation at the production zone is over 40% with a thickness of 90 m,showing the interbedded distribution with different boundaries between gas hydrate-and free gas-bearing layers.However,the gas hydrate saturation value at the adjacent canyon is 70%,with 30-m-thick patches and linear features.The lithological and fault controls on gas hydrate and free gas distributions are demonstrated by tracing each gas hydrate-bearing layer.Moreover,the BSR depths based on broad-band reprocessed 3D seismic data not only exhibit variations due to small-scale topographic changes caused by seafloor sedimentation and erosion but also show the upward shift of BSR and the blocky distribution of the coexistence of gas hydrate and free gas in the Pearl River Mouth Basin. 展开更多
关键词 gas hydrate free gas shift of BSR broad-band processing
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Symptom experience in patients with cancer-related fatigue:A systematic review and meta-synthesis
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作者 Ke PENG Mi ZHANG +2 位作者 Jie ZHANG Dan YANG Ling TANG 《Journal of Integrative Nursing》 2022年第4期193-201,共9页
To understand the real experiences of patients with cancer-related fatigue and to promote quality of life,the researchers used computer searches of PubMed,EMbase,CINAHL,PsycINFO,Web of Science,and China National Knowl... To understand the real experiences of patients with cancer-related fatigue and to promote quality of life,the researchers used computer searches of PubMed,EMbase,CINAHL,PsycINFO,Web of Science,and China National Knowledge Infrastructure,China Biology Medicine disc,Wanfang Data,China Science and Technology Journal Database for relevant qualitative studies from the inception to November 1,2021.The results showed that a total of 16 papers were included,and 57 outcomes were distilled into 9 categories,which were pooled into four integrated outcomes,such as somatic,psychological and social support and so on.It is concluded that patients with cancer-related fatigue are not only in the midst of multidimensional,unspeakable somatic experiences,and complex psychological experiences,they are also hindered in coping with fatigue symptom and social life.Therefore,healthcare professionals should provide health interventions and psychological support to those patients whenever possible. 展开更多
关键词 Cancer-related fatigue meta-synthesis patient experience qualitative research systematic review
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Women’s Perception Concerning Health Care in the Post-Partum Period: A Meta-Synthesis
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作者 Maria Suely Correa Katia Virginia Feliciano +1 位作者 Evelyne Nascimento Pedrosa Ariani Impieri Souza 《Open Journal of Obstetrics and Gynecology》 2014年第7期416-426,共11页
This meta-synthesis presents the results of qualitative studies on puerperal perception concerning woman’s care in the post-partum period. Four databases were researched using keywords such as “postnatal care” (or)... This meta-synthesis presents the results of qualitative studies on puerperal perception concerning woman’s care in the post-partum period. Four databases were researched using keywords such as “postnatal care” (or) “postpartum period”, (and) “care”, “women”, “perception”, “qualitative research”, “women’s health services”, “community health services”, “allied health personnel”, “primary health care”, resulting in 9 articles for analysis. Six themes were identified: interpersonal relationship, information, communication, attending the necessities, service organization and other supports. Results report mainly on the unsatisfactory professional care for women, appreciating the form of dealing with promptness and the timing to be attended;trust;content, coherence and the way to inform;clarification of doubts;friendly conversation and clinical assistance. The professional workload was restricted on postpartum period care quality. There were gaps found in clinical practice and in dialogical communication and information on women’s health necessities. 展开更多
关键词 POST-PARTUM CARE Qualitative Research meta-synthesis Women’s HEALTH Needs Assessment
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Design and optimization of a greener sinomenine hydrochloride preparation process considering variations among different batches of the medicinal herb 被引量:1
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作者 Dandan Ren Jiale Xie +2 位作者 Tianle Chen Haibin Qu Xingchu Gong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期77-90,共14页
The current methods used to industrially produce sinomenine hydrochloride involve several issues,including high solvent toxicity,long process flow,and low atomic utilization efficiency,and the greenness scores of the ... The current methods used to industrially produce sinomenine hydrochloride involve several issues,including high solvent toxicity,long process flow,and low atomic utilization efficiency,and the greenness scores of the processes are below 65 points.To solve these problems,a new process using anisole as the extractant was proposed.Anisole exhibits high selectivity for sinomenine and can be connected to the subsequent water-washing steps.After alkalization of the medicinal material,heating extraction,water washing,and acidification crystallization were carried out.The process was modeled and optimized.The design space was constructed.The recommended operating ranges for the critical process parameters were 3.0–4.0 h for alkalization time,60.0–80.0℃ for extraction temperature,2.0–3.0(volume ratio)for washing solution amount,and 2.0–2.4 mol·L^(-1) for hydrochloric acid concentration.The new process shows good robustness because different batches of medicinal materials did not greatly impact crystal purity or sinomenine transfer rate.The sinomenine transfer rate was about 20%higher than that of industrial processes.The greenness score increased to 90 points since the novel process proposed in this research solves the problems of long process flow,high solvent toxicity,and poor atomic economy,better aligning with the concept of green chemistry. 展开更多
关键词 Sinomenine hydrochloride process optimization ANISOLE
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Investigation on taste characteristics and sensory perception of soft-boiled chicken during oral processing based on electronic tongue and electronic nose 被引量:1
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作者 Na Xu Xianming Zeng +3 位作者 Peng Wang Xing Chen Xinglian Xu Minyi Han 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期313-326,共14页
The sensory perception of food is a dynamic process,which is closely related to the release of flavor substances during oral processing.It’s not only affected by the food material,but also subjected to the individual... The sensory perception of food is a dynamic process,which is closely related to the release of flavor substances during oral processing.It’s not only affected by the food material,but also subjected to the individual oral environment.To explore the oral processing characteristics of soft-boiled chicken,the sensory properties,texture,particle size,viscosity,characteristic values of electronic nose and tongue of different chicken samples were investigated.The correlation analysis showed that the physical characteristics especially the cohesiveness,springiness,resilience of the sample determined oral processing behavior.The addition of chicken skin played a role in lubrication during oral processing.The particle size of the bolus was heightened at the early stage,and the fluidity was enhanced in the end,which reduced the chewing time to the swallowing point and raised the aromatic compounds signal of electronic nose.But the effect of chicken skin on chicken thigh with relatively high fat content,was opposite in electronic nose,which had a certain masking effect on the perception of umami and sweet taste.In conclusion,fat played a critical role in chicken oral processing and chicken thigh had obvious advantages in comprehensive evaluation of soft-boiled chicken,which was more popular among people. 展开更多
关键词 Oral processing CHICKEN Electronic tongue Electronic nose
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Toluene Processed All-Polymer Solar Cells with 18%Efficiency and Enhanced Stability Enabled by Solid Additive:Comparison Between Sequential-Processing and Blend-Casting 被引量:1
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作者 Guoping Zhang Chaoyue Zhao +13 位作者 Liangxiang Zhu Lihong Wang Wenzhao Xiong Huawei Hu Qing Bai Yaping Wang Chen Xie Peng You He Yan Dan Wu Tao Yang Mingxia Qiu Shunpu Li Guangye Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第4期247-254,共8页
The emergence of polymerized small molecule acceptors(PSMAs)has significantly improved the performance of all-polymer solar cells(all-PSCs).However,the pace of device engineering lacks behind that of materials develop... The emergence of polymerized small molecule acceptors(PSMAs)has significantly improved the performance of all-polymer solar cells(all-PSCs).However,the pace of device engineering lacks behind that of materials development,so that a majority of the PSMAs have not fulfilled their potentials.Furthermore,most high-performance all-PSCs rely on the use of chloroform as the processing solvent.For instance,the recent highperformance PSMA,named PJ1-γ,with high LUMO,and HOMO levels,could only achieve a PCE of 16.1%with a high-energy-level donor(JD40)using chloroform.Herein,we present a methodology combining sequential processing(SqP)with the addition of 0.5%wt PC_(71)BM as a solid additive(SA)to achieve an impressive efficiency of 18.0%for all-PSCs processed from toluene,an aromatic hydrocarbon solvent.Compared to the conventional blend-casting(BC)method whose best efficiency(16.7%)could only be achieved using chloroform,the SqP method significantly boosted the device efficiency using toluene as the processing solvent.In addition,the donor we employ is the classic PM6 that has deeper energy levels than JD40,which provides low energy loss for the device.We compare the results with another PSMA(PYF-T-o)with the same method.Finally,an improved photostability of the SqP devices with the incorporation of SA is demonstrated. 展开更多
关键词 all-polymers solar cells sequential processing solid additive
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Study on the coupling calculation method for the launch dynamics of a self-propelled artillery multibody system considering engraving process 被引量:1
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作者 Shujun Zhang Xiaoting Rui +1 位作者 Hailong Yu Xiaoli Dong 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期67-85,共19页
The launch dynamics theory for multibody systems emerges as an innovative and efficacious approach for the study of launch dynamics,capable of addressing the challenges of complex modeling,diminished computational eff... The launch dynamics theory for multibody systems emerges as an innovative and efficacious approach for the study of launch dynamics,capable of addressing the challenges of complex modeling,diminished computational efficiency,and imprecise analyses of system dynamic responses found in the dynamics research of intricate multi-rigid-flexible body systems,such as self-propelled artillery.This advancement aims to enhance the firing accuracy and launch safety of self-propelled artillery.Recognizing the shortfall of overlooking the band engraving process in existing theories,this study introduces a novel coupling calculation methodology for the launch dynamics of a self-propelled artillery multibody system.This method leverages the ABAQUS subroutine interface VUAMP to compute the dynamic response of the projectile and barrel during the launch process of large-caliber self-propelled artillery.Additionally,it examines the changes in projectile resistance and band deformation in relation to projectile motion throughout the band engraving process.Comparative analysis of the computational outcomes with experimental data evidences that the proposed method offers a more precise depiction of the launch process of self-propelled artillery,thereby enhancing the accuracy of launch dynamics calculations for self-propelled artillery. 展开更多
关键词 Self-propelled artillery Engraving process Multibody system dynamics Launch dynamics
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Effects of friction stir processing and nano-hydroxyapatite on the microstructure,hardness,degradation rate and in-vitro bioactivity of WE43 alloy for biomedical applications 被引量:1
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作者 Bo Wu Farazila Yusof +5 位作者 Fuguo Li Huan Miao A.R.Bushroa Mohd Ridha Bin Muhamad Irfan Anjum Badruddin Mahmoud Z.Ibrahim 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期209-224,共16页
Nowadays,magnesium alloys are emerging in biomedical implants for their similar properties to natural bones.However,the rapid degradation of magnesium alloys in biological media hinders successful implantation.Refinem... Nowadays,magnesium alloys are emerging in biomedical implants for their similar properties to natural bones.However,the rapid degradation of magnesium alloys in biological media hinders successful implantation.Refinement of microstructure,as well as reinforcement particles can significantly improve the degradation rate.In this work,multi-pass friction stir processing(FSP)was proposed to synthesize WE43/nano-hydroxyapatite(n HA)surface composite,the microstructure,reinforced particle distribution,micro-hardness,corrosion behavior and in-vitro bioactivity were studied.The subsequent FSP passes of WE43 alloy and WE43/n HA composite refined the grain size which was reduced by 94.29%and 95.92%(2.63 and 1.88μm,respectively)compared to base metal after three passes.This resulted in increasing the microhardness by 120%(90.86 HV0.1)and 135%(105.59 HV0.1)for the WE43 and WE43-n HA,respectively.It is found that increasing FSP passes improved the uniform distribution of n HA particles within the composite matrix which led to improved corrosion resistance and less degradation rate.The corrosion rate of the FSPed WE43/n HA composite after three passes was reduced by 38.2%(4.13 mm/year)and the degradation rate was reduced by 69.7%(2.87 mm/y).This is attributed to secondary phase(Mg24Y5and Mg41Nd5)particle fragmentation and redistribution,as well as a homogeneous distribution of n HA.Additionally,the growing Ca-P and Mg(OH)2layer formed on the surface represented a protective layer that reduced the degradation rate.The wettability test revealed a relatively hydrophilic surface with water contact angle of 49.1±2.2°compared to 71.2±2.1°for base metal.Also,biomineralization test showed that apatite layer grew after immersion 7d in simulated body fluid with atomic ratio of Ca/P 1.60 approaching the stoichiometric ratio(1.67)indicating superior bioactivity of FSPed WE43/n HA composite after three passes.These results raise that the grain refinement by FSP and introduction of n HA particles significantly improved the degradation rate and in-vitro bioactivity of WE43 alloy for biomedical applications. 展开更多
关键词 Friction stir processing Magnesium-based composite NANO-HYDROXYAPATITE Corrosion behavior In-vitro bioactivity
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Pressure stimulated current in progressive failure process of combined coal-rock under uniaxial compression:Response and mechanism 被引量:1
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作者 Tiancheng Shan Zhonghui Li +7 位作者 Xin Zhang Haishan Jia Xiaoran Wang Enyuan Wang Yue Niu Dong Chen Weichen Sun Dongming Wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期227-243,共17页
Effective monitoring of the structural health of combined coal-rock under complex geological conditions by pressure stimulated currents(PSCs)has great potential for the understanding of dynamic disasters in undergroun... Effective monitoring of the structural health of combined coal-rock under complex geological conditions by pressure stimulated currents(PSCs)has great potential for the understanding of dynamic disasters in underground engineering.To reveal the effect of this way,the uniaxial compression experiments with PSC monitoring were conducted on three types of coal-rock combination samples with different strength combinations.The mechanism explanation of PSCs are investigated by resistivity test,atomic force microscopy(AFM)and computed tomography(CT)methods,and a PSC flow model based on progressive failure process is proposed.The influence of strength combinations on PSCs in the progressive failure process are emphasized.The results show the PSC responses between rock part,coal part and the two components are different,which are affected by multi-scale fracture characteristics and electrical properties.As the rock strength decreases,the progressive failure process changes obviously with the influence range of interface constraint effect decreasing,resulting in the different responses of PSC strength and direction in different parts to fracture behaviors.The PSC flow model is initially validated by the relationship between the accumulated charges of different parts.The results are expected to provide a new reference and method for mining design and roadway quality assessment. 展开更多
关键词 Combined coal-rock Pressure stimulated current Progressive failure process MECHANISM Flow model
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A new insight into LPSO phase transformation and mechanical properties uniformity of large-scale Mg-Gd-Y-Zn-Zr alloy prepared by multi-pass friction stir processing 被引量:1
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作者 Xiaohu Guan Wen Wang +7 位作者 Ting Zhang Pai Peng Qiang Liu Peng Han Ke Qiao Jun Cai Liqiang Wang Kuaishe Wang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第5期2041-2056,共16页
A large-scale fine-grained Mg-Gd-Y-Zn-Zr alloy plate with high strength and ductility was successfully prepared by multi-pass friction stir processing(MFSP)technology in this work.The structure of grains and long peri... A large-scale fine-grained Mg-Gd-Y-Zn-Zr alloy plate with high strength and ductility was successfully prepared by multi-pass friction stir processing(MFSP)technology in this work.The structure of grains and long period stacking ordered(LPSO)phase were characterized,and the mechanical properties uniformity was investigated.Moreover,a quantitative relationship between the microstructure and tensile yield strength was established.The results showed that the grains in the processed zone(PZ)and interfacial zone(IZ)were refined from 50μm to 3μm and 4μm,respectively,and numerous original LPSO phases were broken.In IZ,some block-shaped 18R LPSO phases were transformed into needle-like 14H LPSO phases due to stacking faults and the short-range diffusion of solute atoms.The severe shear deformation in the form of kinetic energy caused profuse stacking fault to be generated and move rapidly,greatly increasing the transformation rate of LPSO phase.After MFSP,the ultimate tensile strength,yield strength and elongation to failure of the large-scale plate were 367 MPa,305 MPa and 18.0% respectively.Grain refinement and LPSO phase strengthening were the major strengthening mechanisms for the MFSP sample.In particularly,the strength of IZ was comparable to that of PZ because the strength contribution of the 14H LPSO phase offsets the lack of grain refinement strengthening in IZ.This result opposes the widely accepted notion that IZ is a weak region in MFSP-prepared large-scale fine-grained plate. 展开更多
关键词 Friction stir processing MULTI-PASS Mg-Gd-Y-Zn-Zr alloy LPSO phase transformation Mechanical properties
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Recent developments in selective laser processes for wearable devices 被引量:1
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作者 Youngchan Kim Eunseung Hwang +3 位作者 Chang Kai Kaichen Xu Heng Pan Sukjoon Hong 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期517-547,共31页
Recently,the increasing interest in wearable technology for personal healthcare and smart virtual/augmented reality applications has led to the development of facile fabrication methods.Lasers have long been used to d... Recently,the increasing interest in wearable technology for personal healthcare and smart virtual/augmented reality applications has led to the development of facile fabrication methods.Lasers have long been used to develop original solutions to such challenging technological problems due to their remote,sterile,rapid,and site-selective processing of materials.In this review,recent developments in relevant laser processes are summarized under two separate categories.First,transformative approaches,such as for laser-induced graphene,are introduced.In addition to design optimization and the alteration of a native substrate,the latest advances under a transformative approach now enable more complex material compositions and multilayer device configurations through the simultaneous transformation of heterogeneous precursors,or the sequential addition of functional layers coupled with other electronic elements.In addition,the more conventional laser techniques,such as ablation,sintering,and synthesis,can still be used to enhance the functionality of an entire system through the expansion of applicable materials and the adoption of new mechanisms.Later,various wearable device components developed through the corresponding laser processes are discussed,with an emphasis on chemical/physical sensors and energy devices.In addition,special attention is given to applications that use multiple laser sources or processes,which lay the foundation for the all-laser fabrication of wearable devices. 展开更多
关键词 Selective laser process Wearable device Transformative approach Laser-induced graphene Ablation SINTERING Synthesis
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