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Overcoming exhaustion:Building a conceptual foundation for nursing research
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作者 Bridget Webb Suzy Walter 《International Journal of Nursing Sciences》 2025年第6期588-592,共5页
Objectives:This study aimed to establish the concept of overcoming exhaustion,providing a reference basis for nursing management and conducting related nursing research.Methods:Liehr and Smith’s three-phase,nine-step... Objectives:This study aimed to establish the concept of overcoming exhaustion,providing a reference basis for nursing management and conducting related nursing research.Methods:Liehr and Smith’s three-phase,nine-step concept-building process was used to create the concept of overcoming exhaustion.The nine steps were as follows:1)write a practice story;2)name the emerging concept;3)select a theoretical lens;4)link concept to literature;5)gather a concept story;6)identify final core qualities;7)formulate concept definition;8)create a concept model;and 9)specify the concept building synthesis.Results:The concept of overcoming exhaustion was identified based on the elements of a practice story,the life experiences of nurses who struggle with the demands of caring for their patients,their families,and themselves.The theory of self-transcendence was then recognized as the theoretical lens from which to ground the concept.The core qualities,despair and moments of calmness,were derived from the literature and confirmed through a concept story.A definition of the concept integrating the core qualities was formed:overcoming exhaustion involves realizing moments of calmness amidst despair.A model was created to demonstrate the relationship between core qualities,despair,and moments of calmness.Conclusions:The concept of overcoming exhaustion was developed and,through the concept-building process,was defined as realizing moments of calmness amidst despair.By identifying the complexities of overcoming exhaustion,this work lays the foundation for a future research program to develop understanding and interventions that support nurse well-being in the context of ongoing personal and professional demands. 展开更多
关键词 BURNOUT Concept building NURSE Overcoming exhaustion Stress
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Does artificial intelligence(AI)anxiety increase employees’deviant behavior toward the organization?The role of emotional exhaustion and leadership support
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作者 Chengcheng Sha Lin Wang Xiaolei Pan 《Journal of Psychology in Africa》 2025年第2期207-214,共8页
This study investigated the relationship between AI anxiety and deviant behavior,as well as the roles of emotional exhaustion and leader support in this context.The sample comprised 381 Chinese e-commerce employees(72... This study investigated the relationship between AI anxiety and deviant behavior,as well as the roles of emotional exhaustion and leader support in this context.The sample comprised 381 Chinese e-commerce employees(72.7%female,age range 21–36 years).The results of the Process model analysis indicate that AI anxiety significantly is associated with higher deviant behaviour.Emotional exhaustion partially mediates this relationship between AI anxiety and employee deviant behavior exacerbating deviant behaviour.Leader support moderates the AI anxiety effect on emotional exhaustion such that when leader support is low.AI anxiety is associated with higher emotional exhaustion among employees.By implication,high levels of leader support can alleviate AI anxiety of employees.Employer organizations should provide appropriate guidance when introducing AI technology to prevent AI anxiety and associated emotional exhaustion and deviant behavior. 展开更多
关键词 AI anxiety emotional exhaustion leader support deviant behavior
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Beyond physical exhaustion:Understanding overtraining syndrome through the lens of molecular mechanisms and clinical manifestation
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作者 Ondrej Fiala Michaela Hanzlova +2 位作者 Lenka Borska Zdenek Fiala Drahomira Holmannova 《Sports Medicine and Health Science》 2025年第4期237-248,共12页
Background Overtraining Syndrome(OTS)is a condition resulting from excessive physical activity without adequate recovery,predominantly affecting elite athletes and military personnel.While overreaching can be a tempor... Background Overtraining Syndrome(OTS)is a condition resulting from excessive physical activity without adequate recovery,predominantly affecting elite athletes and military personnel.While overreaching can be a temporary state,non-functional overreaching may progress to chronic OTS.This review explores various hypotheses regarding the pathogenesis of OTS,including glycogen depletion,dysregulated cytokine response,oxidative stress,and alterations in the autonomic nervous system function.It also highlights the systemic impact of OTS on multiple organ systems,immune function,and overall health,linking the condition to chronic inflammation and an increased disease susceptibility.Additionally,it addresses the role of the gut microbiome in health modulation through physical activity.Methods This narrative review was conducted through a structured search of peer-reviewed journal articles in databases such as PubMed,Web of Science,and Google Scholar,focusing on studies involving human participants and published in English.Results OTS has systemic effects on multiple organ systems,immune function,and overall health,leading to chronic inflammation and increased disease susceptibility.Athletes with OTS exhibit higher morbidity rates,influenced by factors such as sleep deprivation and stress.The review also emphasizes the role of the gut microbiome as a significant modulator of health through physical activity.Conclusion Balanced training and recovery are crucial for preventing OTS and maintaining optimal health and quality of life in physically active individuals.Understanding the complex pathophysiology of OTS is essential for developing effective prevention and treatment strategies. 展开更多
关键词 Overtraining syndrome Overreaching Training Performance exhaustION Inadequate recovery
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The Recovery of PGMs from Spent Automotive Exhaust Catalysts by Lead Slag
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作者 YAN Jisen ZHANG Liao +5 位作者 MAO Shuaidong WANG Zihan PENG Yinli XIE Fang HUA Xijin ZHANG Baojing 《Journal of Wuhan University of Technology(Materials Science)》 2025年第3期871-879,共9页
This paper presented a novel and environmentally friendly approach for recovering platinum group metals(PGMs)from spent automotive exhaust catalysts.The study employed lead slag and waste graphite electrodes as raw ma... This paper presented a novel and environmentally friendly approach for recovering platinum group metals(PGMs)from spent automotive exhaust catalysts.The study employed lead slag and waste graphite electrodes as raw materials,incorporating CaO as an additive to fine-tune the slag's viscosity and density.By reducing FeO in the lead slag using waste graphite electrodes,pure Fe was obtained,effectively trapping the PGMs from the exhausted catalysts.The study explored the effects of reductant addition,trapping duration,slag basicity,and trapping temperature on the recovery rate of PGMs.The results indicated that a maximum recovery rate of 97.86%was achieved when the reductant was added at 1.5 times the theoretical amount,with a trapping duration of 60 minutes,a slag basicity of 0.7,and a trapping temperature of 1600℃.This research offered a greener pathway for the recovery of PGMs from spent automotive exhaust catalysts. 展开更多
关键词 PGMS lead slag RECOVERY spent automotive exhaust catalysts
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Design and Application of an Intelligent Control System for Ceramic Kiln Exhaust Covers Based on 5G and IoT Technology
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作者 ZHAO Zengyi LI Tao +1 位作者 YU Zhongzhan LI Jun 《International Journal of Plant Engineering and Management》 2025年第3期146-160,共15页
Based on 5G and IoT technology,this study addresses the issues of manual control dependency,poor reliability,and high labor costs in traditional ceramic kiln exhaust cover operations.An intelligent control system for ... Based on 5G and IoT technology,this study addresses the issues of manual control dependency,poor reliability,and high labor costs in traditional ceramic kiln exhaust cover operations.An intelligent control system for kiln exhaust covers was designed in this paper.The system employs temperature measurement devices to monitor the internal temperature of the kiln in real time.A controller automatically operates the actuator to open or close the kiln exhaust cover based on temperature measurements.Additionally,the system integrates data transmission units and cloud services,enabling remote monitoring of kiln temperature and historical data storage.Experimental results demonstrate that the system effectively reduces labor costs and significantly enhances the IoT capabilities of kiln operations. 展开更多
关键词 5G IoT ceramic kiln exhaust cover automatic control
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Rumination and Coping as Pathways from Stress to Emotional Exhaustion among Hospital Pharmacists
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作者 Shazia Rehman Erum Rehman Mehmood Ahmad 《International Journal of Mental Health Promotion》 2025年第6期823-843,共21页
Objectives:Emotional exhaustion among healthcare professionals,particularly pharmacists,significantly impacts their well-being and efficacy in patient care.Understanding the psychological mechanisms contributing to em... Objectives:Emotional exhaustion among healthcare professionals,particularly pharmacists,significantly impacts their well-being and efficacy in patient care.Understanding the psychological mechanisms contributing to emotional exhaustion is essential for developing effective interventions.The present research sought to investigate the potential mediating roles of rumination and coping strategies(adaptive and maladaptive)in the relationship between perceived stress and emotional exhaustion among pharmacists.Methods:A cross-sectional survey was carried out between September 2023 and January 2024 involving 576 pharmacists working in public hospitals in Punjab who met the inclusion criteria and actively participated in the study.We employed the Perceived Stress Scale,the Ruminative Response Scale,the Brief Coping Orientation to Problems Experienced Inventory(COPE),and the Oldenburg Burnout Inventory(OLBI)to assess the hypothesized study model.Path analysis was employed to test the hypothesized mediation model,incorporating simple and chain mediation processes.Results:The findings provided empirical evidence supporting a positive association between perceived stress and emotional exhaustion.Rumination significantlymediated this relationship.Further,both adaptive andmaladaptive coping strategieswere found tomediate this relationship,withmaladaptive coping demonstrating amore substantial impact.Conclusion:The chainmediation model demonstrated that rumination and coping strategies(both maladaptive and adaptive)significantly mediate the relationship between perceived stress and emotional exhaustion among pharmacists.Specifically,rumination was found to be a key mediator,with maladaptive coping strategies having a more substantial impact.These findings provide a deeper understanding of the psychological mechanisms contributing to emotional exhaustion in the pharmacy profession. 展开更多
关键词 Perceived stress emotional exhaustion maladaptive coping adaptive coping RUMINATION PHARMACISTS
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Validation Analysis of Gas Chromatography Method for Determining 8 Benzene Derivatives in Fixed Pollution Source Exhaust Gas
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作者 Wenshuai XU Juan LI Ziyan LIN 《Meteorological and Environmental Research》 2025年第4期37-39,42,共4页
Benzene derivatives are volatile organic compounds commonly present in the atmospheric environment,which are toxic and complex in composition.They have become a key regulatory object in China s atmospheric environment... Benzene derivatives are volatile organic compounds commonly present in the atmospheric environment,which are toxic and complex in composition.They have become a key regulatory object in China s atmospheric environment management.In this paper,Shimadzu Nexis GC-2030 gas chromatography was used to simultaneously detect eight benzene derivatives.According to the Environmental Monitoring—Technical Guideline on Drawing and Revising Analytical Method Standards(HJ 168-2010),the monitoring methods for benzene,toluene,ethylbenzene,p-xylene,m-xylene,isopropylbenzene,o-xylene,and styrene in the Stationary Source Emission—Determination of Benzene and Its Analogies—Bags Sampling/Direct Injection—Gas Chromatography(HJ 1261-2022)are verified,and their linear relationships,detection limits,precision and accuracy are analyzed. 展开更多
关键词 Benzene derivatives Fixed pollution source exhaust gas Method validation
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High-temperature oxidation behavior and mechanism of 18Cr-Mo-type ferritic stainless steel containing W and Ce in simulated automotive exhaust gas
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作者 Jia-hao Zheng Yang Feng +1 位作者 Yang Zhao Li-qing Chen 《Journal of Iron and Steel Research International》 2025年第7期2116-2132,共17页
The high melting point element W and the rare earth element Ce were added to 18Cr-Mo(444-type)ferritic stainless steel to improve its high-temperature oxidation resistance in exhaust gas.A simulated exhaust gas was fi... The high melting point element W and the rare earth element Ce were added to 18Cr-Mo(444-type)ferritic stainless steel to improve its high-temperature oxidation resistance in exhaust gas.A simulated exhaust gas was filled in the simultaneous thermal analyzer to simulate the service environment,and the oxidation behavior in high-temperature exhaust gas environment of 444-type ferritic stainless steel alloyed with W and Ce was investigated.The oxide structure and composition formed in this process were analyzed and characterized by scanning electron microscopy/energy-dispersive spectroscopy and electron probe analysis,and the mechanism of W and Ce in the oxidation process was revealed.The results show that 18Cr-Mo ferritic stainless steel containing W and Ce has better oxidation resistance in high-temperature exhaust gas.The element W can promote the precipitation of Laves phase at the matrix/interface,inhibit the interface diffusion of oxidizing elements and prevent the inward growth of the oxide film.The element Ce can suppress the volume of SiO_(2)at the oxide film/interface,reducing the breakaway oxidation caused by cracking of the oxide film.The CeO_(2)provides nucleation sites for oxide particles,promoting the healing of cracks and voids within the oxide film. 展开更多
关键词 Ferritic stainless steel Cerium TUNGSTEN Oxidation behavior Simulated automotive exhaust gas
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The mechanisms and clinical significance of CD8^(+)T cell exhaustion in anti-tumor immunity
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作者 Tao Zhong Shuo Sun +2 位作者 Mingsheng Zhao Bin Zhang Huabao Xiong 《Cancer Biology & Medicine》 2025年第5期460-480,共21页
CD8^(+)T cell exhaustion,a critical challenge in the immune response to cancer,is characterized by a profound decline in the functionality of effector CD8^(+)T cells.This state of exhaustion is accompanied by the upre... CD8^(+)T cell exhaustion,a critical challenge in the immune response to cancer,is characterized by a profound decline in the functionality of effector CD8^(+)T cells.This state of exhaustion is accompanied by the upregulation of various inhibitory receptors and significant shifts in both transcriptional and epigenetic profiles,thus ultimately leading to inadequate tumor control.Therapeutic strategies aimed at reversing CD8^(+)T cell exhaustion have the potential to rejuvenate immune responses and enhance treatment efficacy.This review compiles current knowledge regarding the molecular mechanisms underlying CD8^(+)T cell exhaustion,including the roles of immune checkpoint molecules,the tumor microenvironment,metabolic reprogramming,transcription factors,and epigenetic modifications.Emerging therapeutic approaches designed to combat CD8^(+)T cell exhaustion are evaluated,with emphasis on the modulation of immune checkpoints;targeting of metabolic and transcriptional changes;and exploration of other innovative strategies,such as epigenetic editing and engineered CAR-T cells.Importantly,we expand the exhaustion concept to immune cells beyond CD8^(+)T cells,such as CD4^(+)T cells,natural killer cells,and myeloid populations,thereby highlighting the broader implications of systemic immunosuppression in the cancer context.Finally,we propose avenues for future research aimed at further elucidating the factors and molecular mechanisms associated with CD8^(+)T cell exhaustion,thereby underscoring the critical need for strategies aimed at reversing this state to improve outcomes in cancer immunotherapy. 展开更多
关键词 CD8^(+)T cell exhaustion immune checkpoint immune checkpoint inhibitors cancer immunotherapy anti-tumor immunity
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满足欧Ⅶ排放法规的轻型车制动磨损颗粒物测试装备开发
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作者 谷雨 吕誉 +2 位作者 黄小清 徐辉 曾光 《内燃机工程》 北大核心 2026年第1期48-53,共6页
为了实现欧Ⅶ排放法规对制动磨损颗粒物(brake wear particle,BWP)排放的测试需求,基于联合国全球技术法规第24号(United Nations Global Technical Regulation No.24,UN GTR-24)标准,开发了国内首台满足轻型车BWP排放检测的惯性试验台... 为了实现欧Ⅶ排放法规对制动磨损颗粒物(brake wear particle,BWP)排放的测试需求,基于联合国全球技术法规第24号(United Nations Global Technical Regulation No.24,UN GTR-24)标准,开发了国内首台满足轻型车BWP排放检测的惯性试验台测试系统,并验证了测试系统对UN GTR-24标准的合规性要求。结果表明,该惯性测试实验台的系统级别颗粒背景浓度为:最大流量及最小流量下,直径超过10 nm的总颗粒物数量(记为TPN_(10))及直径超过10 nm的固体颗粒物数量(记为SPN_(10))均为0个/cm^(3)。测试过程中冷却气流温度、湿度和流量均满足UN GTR-24标准的合规性要求;能量耗散偏差低于5%,远低于UN GTR-24标准对能量耗散的合规性要求。BWP排放测试前颗粒背景浓度SPN_(10)为10.1个/cm^(3),TPN_(10)为13.8个/cm^(3);测试后颗粒背景浓度SPN_(10)为7.1个/cm^(3),TPN_(10)为17.3个/cm^(3),均满足UN GTR-24标准要求,证明所开发的BWP测试系统能够用于欧Ⅶ法规开展BWP检测。采用开发的BWP测试系统,对某轻型燃油车的盘式制动器进行的排放测试结果表明,粒径不大于2.5μm的颗粒物(PM_(2.5))质量、粒径不大于10μm的颗粒物(PM10)质量、SPN_(10)和TPN_(10)的排放结果分别为1.6 mg/km、3.9 mg/km、6.03×10^(9)个/km、1.64×10^(10)个/km。 展开更多
关键词 制动器 颗粒物 非尾气颗粒物 欧Ⅶ 测试装备 惯性试验台
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基于改进鹦鹉优化算法的船舶推力分配策略研究
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作者 刘明 娄德成 王晓飞 《海洋工程》 北大核心 2026年第1期163-174,共12页
动力定位系统推力分配求解是一种高度复杂的非线性优化问题,其目标函数和约束条件具有多目标、多约束及非凸特性。传统的推力分配算法在处理该类问题时存在精度低及易陷入局部极值点等问题,而群智能优化算法虽然能够较容易地解决这些问... 动力定位系统推力分配求解是一种高度复杂的非线性优化问题,其目标函数和约束条件具有多目标、多约束及非凸特性。传统的推力分配算法在处理该类问题时存在精度低及易陷入局部极值点等问题,而群智能优化算法虽然能够较容易地解决这些问题,但存在收敛速度慢、寻优结果稳定性差和不可靠等问题。针对上述问题,提出一种多策略融合的鹦鹉优化算法(MSPO),该算法通过分段法和改进混沌法相结合初始化种群,不仅增强初始种群的多样性,而且有效保留了种群中的“精英”个体,为算法稳定收敛和可靠收敛奠定基础;对适应度较差的若干个体执行自适应交叉算子策略,有效提升个体寻优效率、加快算法收敛速度;通过随机选取若干个体并采用广域阿基米德螺线更新方式,增强算法在搜索空间中的遍历性,进一步提升算法全局寻优能力;对最优个体实施多尺度多方向的极尽搜索策略,有利于算法在较少迭代次数内获得可靠且稳定的推力分配解。最后以测试函数和CybershipⅢ船模为对象进行改进算法验证,结果表明改进策略提高了算法收敛的可靠性和稳定性,提升了推力分配精度。 展开更多
关键词 推力分配 鹦鹉优化算法 交叉变异 阿基米德螺线 极尽搜索策略
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多层金属垫片的高温压缩-回弹特性分析
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作者 覃文洁 华青格乐 张金歌 《北京理工大学学报》 北大核心 2026年第1期103-110,共8页
垫片的压缩—回弹曲线是分析螺栓法兰接头的接触情况所必需的,而柴油机排气歧管前端法兰组件中垫片部位的温度通常达到500℃左右,难以通过实验获得.为此针对某高功率柴油机排气歧管前端法兰的多层金属垫片,建立了模拟该垫片压缩-回弹实... 垫片的压缩—回弹曲线是分析螺栓法兰接头的接触情况所必需的,而柴油机排气歧管前端法兰组件中垫片部位的温度通常达到500℃左右,难以通过实验获得.为此针对某高功率柴油机排气歧管前端法兰的多层金属垫片,建立了模拟该垫片压缩-回弹实验的有限元模型,通过接触动力学分析得到了其在室温和200℃下的压缩—回弹曲线,并与相应的实验结果对比,验证了所建模型的准确性,进一步分析得到了高温下该垫片的压缩−回弹曲线.结果表明常温时垫片的最大压缩量为0.522 mm,温度升至700℃时最大压缩量则升至0.762 mm,同时中间层垫片发生塑性变形的临界载荷减小,曲线的压缩段与回弹段的间距也增大.使用室温以及500℃下的垫片压缩—回弹曲线计算柴油机排气歧管前端法兰的接触应力,得到垫片最小接触应力分别为5.57 MPa和6.95 MPa,误差达到20%,说明采用不同温度的垫片压缩-回弹曲线对排气歧管前端法兰的接触应力分布计算会造成较大影响. 展开更多
关键词 多层金属垫片 排气歧管前端法兰 压缩-回弹 高温影响
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基于“阳化气,阴成形”理论探讨不明原因复发性流产病机与治疗
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作者 赵鑫 冯晓玲 《吉林中医药》 2026年第1期15-19,共5页
复发性流产(RSA)属中医学“滑胎”范畴,以阳气虚衰则胎失温煦、阴血不足则胞失濡养、阳热亢盛则扰动胎元等阴阳失衡为枢机,以痰瘀阻滞则胞脉闭塞为框架,系统阐释阳气虚衰、阴血不足、阳热亢盛、痰瘀阻滞等核心病机与现代生殖指标的对应... 复发性流产(RSA)属中医学“滑胎”范畴,以阳气虚衰则胎失温煦、阴血不足则胞失濡养、阳热亢盛则扰动胎元等阴阳失衡为枢机,以痰瘀阻滞则胞脉闭塞为框架,系统阐释阳气虚衰、阴血不足、阳热亢盛、痰瘀阻滞等核心病机与现代生殖指标的对应关系。临床以经典方剂为核心,传承《黄帝内经》“阳生阴长”经典理论,通过Th1/Th2平衡、滋养细胞侵袭等现代机制予以验证,为复发性流产防治提供理法方药兼备的完整体系,彰显中医“阴阳和合”的理论价值。 展开更多
关键词 复发性流产 阳生阴长 阳气虚衰
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Study on the effect of moxibustion at “Shénquè”(神阙 CV 8) on the immune system of rats taking long-term exhaustive exercise 被引量:5
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作者 梁玉磊 许晓康 +7 位作者 周小红 高飞 孙立虹 祝婕 张闯 丁晨光 李晓峰 李新华 《World Journal of Acupuncture-Moxibustion》 CSCD 2017年第2期43-47,共5页
Objective To explore the effect of moxibustion at "Shénquè"(神阙 CV 8) on the immune system of rats taking long-term exhaustive exercise.Method Thirty male SD rats were randomly divided into blank group,... Objective To explore the effect of moxibustion at "Shénquè"(神阙 CV 8) on the immune system of rats taking long-term exhaustive exercise.Method Thirty male SD rats were randomly divided into blank group,model group and moxibustion group with 10 rats in each group.Except the rats in blank group,all the rats were established into long-term exhaustive models through swimming again and again.Mild moxibustion at CV 8 for 15 min was carried out in the rats in moxibustion group after modeling.The treatment was conducted once every other day,and treatment for 10 times was needed.The exhaustive duration for each time was recorded,the levels of serum Ig A,Ig G,Ig M and ACP were detected 24 h after the 10 th exhaustive exercise,and the histomorphological changes of spleen were observed.Immunoturbidimetry was adopted for detecting the Ig A level,and ELISA method was used for detecting the levels of Ig G,Ig M and ACP.Results The common exhaustive duration in moxibustion group was longer than that in model group,however,the time difference was statistically significant after the 5th exhaustive exercise(P0.01).The levels of serum IgG and IgM in model group were lower than that in blank group(all P0.01),and the serum ACP level in model group was higher than that in blank group(P0.01),indicating that the splenic histomorphology was damaged.The levels of serum Ig G and Ig M in moxibustion group were higher than that in model group(all P0.01),and the serum ACP level in moxibustion group was lower than that in model group,showing that the splenic histomorphology was repaired.Conclusion Moxibustion at CV 8 can improve the levels of immunoglobulin(Ig G,Ig A,Ig M) of tired body for a long time,decrease the ACP level,and repair the damaged spleen tissues. 展开更多
关键词 Mild moxibustion Shénquè(神阙CV 8) exhaustive duration IMMUNOGLOBULIN ACP spleen tissue
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INVESTIGATION IN REDUCING EXHAUST EMISSIONS FROM TWO STROKE MOTORCYCLES 被引量:1
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作者 王颂秦 白景升 林漫群 《Transactions of Tianjin University》 EI CAS 1998年第1期3-8,共6页
Test results of reducing two stroke motorcycle emissions with new type carburettors and electronic fuel injection systems are presented. Analyses and comparison between different systems are discussed. The adoption o... Test results of reducing two stroke motorcycle emissions with new type carburettors and electronic fuel injection systems are presented. Analyses and comparison between different systems are discussed. The adoption of electronically controlled injection and corresponding electronic control technique is an effective measure of prolonged vitality to improve emissions from two stroke motorcycles. Suggestions about the strategic steps of China′s motorcycle emission control are proposed. 展开更多
关键词 two stroke motorcycle engine carburettor electronic control injection system controlled stratified combustion emission test for exhaust emission from motorcycle
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Computation of Electromagnetic Properties of Mildly Overexpanded and Underexpanded Rocket Exhaust Plume
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作者 刘青云 黄振宇 +1 位作者 张平 徐文灿 《Journal of Beijing Institute of Technology》 EI CAS 2000年第2期217-224,共8页
An improved near far field divided coupled method was established to investigate the electromagnetic properties of mildly overexpanded and underexpanded rocket exhaust plumes. Firstly, axisymmetric Navier Stokes eq... An improved near far field divided coupled method was established to investigate the electromagnetic properties of mildly overexpanded and underexpanded rocket exhaust plumes. Firstly, axisymmetric Navier Stokes equations incorporated with k ε two equation turbulence models were solved using time dependent approach to calculate the pressure of the near filed. Secondly, parabolized axisymmetric Navier Stokes equations incorporated with finite rate chemical kinetics models were marching on the detailed pressure map of the near field. The termination of the near field would yield the initial line for the far field. In addition, in the far field, the spatial marching method was directly used under the constant pressure condition, but considering more complicated chemically reacting process. Finally, the electromagnetic parameters of the whole plume were calculated with the electron conductive model. The calculated results of the overexpanded and underexpanded rocket exhaust plume were discussed. The predicted microwave attenuation accorded with the experimental results. This improved method is feasible for calculating the microwave attenuation characteristics of mildly non fully expanded rocket exhaust plumes. 展开更多
关键词 rocket exhaust plume microwave attenuation numerical simulation
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ExperimentonPerformanceofLow-TemperatureExhaustSteamReclamation 被引量:2
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作者 严俊杰 武心壮 +1 位作者 种道彤 周晓丽 《西安交通大学学报》 EI CAS CSCD 北大核心 2009年第5期8-12,共5页
针对不同的喉嘴距、面积比,实验研究了不同的进水压力、进水温度和出水压力对低温乏汽回收利用装置性能的影响规律.发现在进水压力为0.14~O.50MPa、进水温度为23~60℃、出水压力为0.096-0.110MPa,以及4种喉嘴距、3种面积比的... 针对不同的喉嘴距、面积比,实验研究了不同的进水压力、进水温度和出水压力对低温乏汽回收利用装置性能的影响规律.发现在进水压力为0.14~O.50MPa、进水温度为23~60℃、出水压力为0.096-0.110MPa,以及4种喉嘴距、3种面积比的实验条件范围内,随着喉嘴距和面积比的增加,加热温升和流量比先增大后减小,得到最佳归一化喉嘴距L=4.50,以及最佳面积比m=6.25,使得加热温升和流量比最大.同时,加热温升和流量比均随着进水压力和进水温度的增加而减小,当出水压力升高时,装置性能变差,加热温升和流量比均减小. 展开更多
关键词 乏汽回收 喉嘴距 面积比 加热温升 流量比
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停车时长对轻型汽油车尾气VOCs排放影响
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作者 陈宏飞 付明亮 +6 位作者 吴晛 谢沛远 韩全康 王运静 程亚伦 朱仁成 丁焰 《环境工程技术学报》 北大核心 2026年第1期254-261,共8页
停车时长与汽车再次启动时油气雾化程度、机油温度、三元催化器(TWC)温度等密切相关,进而影响尾气污染物排放。为探明停车时长对汽车尾气VOCs排放的影响,基于整车转毂排放测试系统,开展典型国VI轻型汽油车在不同停车时长(t<0.5h、1.5... 停车时长与汽车再次启动时油气雾化程度、机油温度、三元催化器(TWC)温度等密切相关,进而影响尾气污染物排放。为探明停车时长对汽车尾气VOCs排放的影响,基于整车转毂排放测试系统,开展典型国VI轻型汽油车在不同停车时长(t<0.5h、1.5 h<t<4 h和t>6 h)下的排放测试,对尾气中VOCs进行采样和组分分析,并利用最大增量反应活性法(MIR)测算其臭氧生成潜势(OFP)。结果表明:随着t<0.5 h增加到t>6 h,汽油车尾气VOCs平均排放因子由10.9 mg/km增加至30.6 mg/km,OFP由26.1 mg/km增加至109.4 mg/km,其中烯烃、芳香烃等高活性物种排放占比显著增加。t>1.5 h时,前589 s(启动阶段)排放的VOCs占全工况(1 800 s)的75%以上,OFP相对贡献占全工况85%以上。建议结合我国汽车使用特征,构建考虑停车时长参数的精细化VOCs排放清单,并针对长停车工况下冷启动阶段VOCs高排放特性,开发精准控制技术。 展开更多
关键词 轻型汽油车 停车时长 尾气排放 挥发性有机物 臭氧生成潜势(OFP)
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Transitional Road of Resources-exhausted Cities to Low-carbon Economy:Tourism Resources Development——A Case Study of Gejiu City 被引量:2
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作者 张家友 胡剑波 《Journal of Landscape Research》 2011年第1期95-99,共5页
Tourism is of vital practical significance to low-carbon economic transition of resources-exhausted cities.By taking Gejiu City of Yunnan Province for example,the paper discussed that Gejiu City as the resources-exhau... Tourism is of vital practical significance to low-carbon economic transition of resources-exhausted cities.By taking Gejiu City of Yunnan Province for example,the paper discussed that Gejiu City as the resources-exhausted city should positively develop tourism,particularly industrial heritage tourism,treating tourism development as the breakthrough and motive power of low-carbon economic transition of resources-exhausted cities,so as to walk out a unique road of tourism promoting low-carbon economic development. 展开更多
关键词 Resources-exhausted CITY Low-carbon economy TOURISM resources Industrial HERITAGE TOURISM
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