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Shear behaviors of intermittent joints subjected to shearing cycles under constant normal stiffness conditions:Effects of loading parameters 被引量:1
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作者 Bin Wang Yujing Jiang +1 位作者 Qiangyong Zhang Hongbin Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期2695-2712,共18页
A conceptual model of intermittent joints is introduced to the cyclic shear test in the laboratory to explore the effects of loading parameters on its shear behavior under cyclic shear loading.The results show that th... A conceptual model of intermittent joints is introduced to the cyclic shear test in the laboratory to explore the effects of loading parameters on its shear behavior under cyclic shear loading.The results show that the loading parameters(initial normal stress,normal stiffness,and shear velocity)determine propagation paths of the wing and secondary cracks in rock bridges during the initial shear cycle,creating different morphologies of macroscopic step-path rupture surfaces and asperities on them.The differences in stress state and rupture surface induce different cyclic shear responses.It shows that high initial normal stress accelerates asperity degradation,raises shear resistance,and promotes compression of intermittent joints.In addition,high normal stiffness provides higher normal stress and shear resistance during the initial cycles and inhibits the dilation and compression of intermittent joints.High shear velocity results in a higher shear resistance,greater dilation,and greater compression.Finally,shear strength is most sensitive to initial normal stress,followed by shear velocity and normal stiffness.Moreover,average dilation angle is most sensitive to initial normal stress,followed by normal stiffness and shear velocity.During the shear cycles,frictional coefficient is affected by asperity degradation,backfilling of rock debris,and frictional area,exhibiting a non-monotonic behavior. 展开更多
关键词 Intermittent joint Cyclic shear Loading parameter Constant normal stiffness(CNS)
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Revisiting scale effect on joint roughness coefficient and shear strength considering sampling methods and geometric characteristics
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作者 Qing Lü Xueheng Cai +2 位作者 Luxiang Wu Jun Zheng Bo Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期2843-2856,共14页
The scale effect on shear strength of rock joints is well-documented.However,whether scale effects are negative,positive,or even exist or not is still controversial.Joint roughness significantly influences the shear s... The scale effect on shear strength of rock joints is well-documented.However,whether scale effects are negative,positive,or even exist or not is still controversial.Joint roughness significantly influences the shear strength of rock joints.Compared to the shear tests,using the joint roughness coefficient(JRC)and its roughness parameters offers a more convenient method for describing the scale effect on shear strength.However,it is crucial to understand that the scale effect mechanisms of JRC are distinct from those of shear strength.Therefore,this paper aims to clarify these distinct mechanisms.By digitally extracting roughness parameters from granite samples,it is found that the scale effect of roughness parameters mainly comes from the sampling methods and the geometric characteristics of parameters.Furthermore,a full data sampling method considering heterogeneity is proposed to obtain more representative roughness parameters.To reveal the scale effect mechanisms of shear strength,Gaussian filtering is firstly used to separate the waviness and unevenness components of roughness,facilitating a deeper understanding of the geometric characteristics of roughness.It is suggested that the wavelength of the waviness component can reflect the scale effect on shear strength.Secondly,numerical simulations of ideal artificial joint models are conducted to validate that the wavelength of the waviness component serves as the dividing point between positive and negative scale effects.The mechanical mechanisms of positive and negative scale effects are also interpreted.Finally,these mechanisms successfully elucidate the occurrence patterns of the scale effect on natural joint profiles. 展开更多
关键词 Rock joint joint roughness coefficient(JRC) Shear strength Scale effect
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Entropy Consistency-Based Adaptive Sampling Method for Determining the Scale Effect in the Joint Roughness Coefficient
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作者 Jibo Qin Jun Ye +1 位作者 Xiaoming Sun Shigui Du 《Journal of Earth Science》 2025年第2期644-653,共10页
The joint roughness coefficient(JRC) is one of the key parameters for evaluating the shear strength of rock joints.Because of the scale effect in the JRC,reliable JRC values are of great importance for most rock engin... The joint roughness coefficient(JRC) is one of the key parameters for evaluating the shear strength of rock joints.Because of the scale effect in the JRC,reliable JRC values are of great importance for most rock engineering projects.During the collection process of JRC samples,the redundancy or insufficiency of representative rock joint surface topography(RJST) information in serial length JRC samples is the essential reason that affects the reliability of the scale effect results.Therefore,this paper proposes an adaptive sampling method,in which we use the entropy consistency measure Q(a) to evaluate the consistency of the joint morphology information contained in adjacent JRC samples.Then the sampling interval is automatically adjusted according to the threshold Q(at) of the entropy consistency measure to ensure that the degree of change of RJST information between JRC samples is the same,and ultimately makes the representative RJST information in the collected JRC samples more balanced.The application results of actual cases show that the proposed method can obtain the scale effect in the JRC efficiently and reliably. 展开更多
关键词 sampling method joint roughness coefficient(JRC) scale effect entropy consistency measure rock joint engineering geology
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Therapeutic effect of the sternoclavicular hook plate in severe trauma patients with sternoclavicular joint injuries:from a level-Ⅰ trauma center
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作者 Pengchao Guo Nan Li +2 位作者 Huiming Zhong Guangfeng Zhao Zhijun Pan 《World Journal of Emergency Medicine》 2025年第3期273-276,共4页
The clinical treatment of severe trauma withsternoclavicular joint injury is challenging,primarilydue to the irregular shape of the bones surrounding thesternoclavicular joint,as well as the posterior clavicle beingcl... The clinical treatment of severe trauma withsternoclavicular joint injury is challenging,primarilydue to the irregular shape of the bones surrounding thesternoclavicular joint,as well as the posterior clavicle beingclose to the aorta and mediastinal organs.^([1])These patientsnot only suffer direct injuries to the sternoclavicularjoint,but also frequently experience severe injuries toother body parts.The systemic physiological disordersand multi-organ dysfunction caused by severe traumaincrease the surgery di?culty and mortality risk.^([2]) 展开更多
关键词 sternoclavicular joint injury mediastinal organs severe traumaincrease therapeutic effect surgery di systemic physiological disordersand severe trauma joint injury
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Control of the magnonic excitation under the joint mechanism of magnetostrictive effect and magnetocrystalline anisotropy
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作者 Saisai Yu Junbo Liu Hao Xiong 《Chinese Physics B》 2025年第6期183-190,共8页
Magnetostrictive effects and magnetocrystalline anisotropy are fundamental physical properties governing magnon dynamics in magnetic systems. Recent evidence shows that strain-mediated magnetostrictive coupling provid... Magnetostrictive effects and magnetocrystalline anisotropy are fundamental physical properties governing magnon dynamics in magnetic systems. Recent evidence shows that strain-mediated magnetostrictive coupling provides an effective pathway for modulating magnonic excitation through quantum interference. Nevertheless, the microscopic origins of magnetocrystalline anisotropy in manipulating magnon excitation pathways, particularly regarding magnonic Kerr nonlinearity and crystal direction constraints, require further investigation. In this study, we construct a dual-frequency driven magnomechanical model based on yttrium iron garnet(YIG) spheres. By introducing a Hamiltonian with the magnonic Kerr nonlinear term, we combine the Heisenberg–Langevin equations and the mean field approximation to analytically solve for the driving efficiency η, and we base our analysis on experimental parameters to evaluate the impacts of the magnonic Kerr coefficient(K), driving field(B_1) and YIG size. The results show that the magnetocrystalline anisotropy induces a MHz-scale frequency shift, splitting the transmission spectrum from a Lorentzian line shape into asymmetric Fano resonance double peaks. The orientation of the external magnetic field(aligned with the [100] or [110] crystallographic axis) allows precise control over the sign of the magnonic Kerr coefficient K, thereby enabling a reversal in the direction of the frequency shift. A strong driving field B_1 not only enables controllable switching of the state but also adjusts the switching bandwidth. Furthermore, we show the transition of the dynamical response mechanism of the excitation efficiency spectrum with varying YIG sphere sizes. The study shows the dynamic control mechanism of the magnetocrystalline anisotropy on magnon switching and provides a theoretical foundation for size optimization and nonlinear energy manipulation in spintronic device design. 展开更多
关键词 magnetostrictive effect Kerr effect optomechanically induced transparency
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Effectiveness of oral vs intravenous acetaminophen on pain management following total joint arthroplasty: A systematic review and meta-analysis
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作者 Bin Lu Ai-Xian Tian +4 位作者 Zheng-Rui Fan Xing-Wen Zhao Hong-Zhen Jin Jian-Xiong Ma Xin-Long Ma 《World Journal of Orthopedics》 2025年第4期69-77,共9页
BACKGROUND In the management of postoperative pain following total joint arthroplasty(TJA),the use of nonsteroidal anti-inflammatory drugs,including acetaminophen,plays a key role in alleviating pain.However,the compa... BACKGROUND In the management of postoperative pain following total joint arthroplasty(TJA),the use of nonsteroidal anti-inflammatory drugs,including acetaminophen,plays a key role in alleviating pain.However,the comparison between intravenous and oral acetaminophen administration in patients undergoing full joint replacement surgery remains controversial.AIM To assess the effectiveness of intravenous and oral acetaminophen in alleviating pain and supporting rehabilitation following TJA.METHODS PubMed,Embase and the Cochrane Library were comprehensively searched to identify cohort studies.The effects of intravenous and oral acetaminophen for managing pain and supporting rehabilitation following TJA were analysed using randomized controlled trials.PRISMA guidelines were followed.The effectiveness of the administration routes was compared based on visual analogue scale(VAS)scores at 24 and 48 h,total morphine usage within 24 h,and total duration of hospital stay.RESULTS The meta-analysis included seven studies comparing intravenous acetaminophen groups and oral acetaminophen groups.The results demonstrated that oral acetaminophen was comparable to intravenous acetaminophen with regard to VAS scores at 24 h and 48 h(P=0.76 and 0.08,respectively).The difference in total morphine use between the two groups was not significant(P=0.22).However,the total hospital stay duration of the intravenous acetaminophen groups was significantly reduced compared to the oral acetaminophen groups(P=0.0005),showing significant advantages in optimizing postoperative recovery and shortening hospitalisation time.CONCLUSION After TJA surgery,intravenous injection of acetaminophen can shorten hospitalisation time and is suitable for rapid analgesia,Oral administration has become the preferred choice for mild cases due to its convenience and economy,providing a basis for clinical drug selection. 展开更多
关键词 joint arthroplasty Pain management META-ANALYSIS ACETAMINOPHEN Nonsteroidal anti-inflammatory drugs
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Effects of bolt joint loosening on the dynamic characteristics of electric angle steel transmission tower
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作者 CAI Yunzhu XING Yujie +1 位作者 XIE Qiang CHENG Xiaowu 《Journal of Southeast University(English Edition)》 2025年第2期180-189,共10页
Transmission towers,serving as the support structure of transmission lines,are significant for the functional-ity of an electric transmission system.Bolt joint loosening is one of the critical factors that can affect ... Transmission towers,serving as the support structure of transmission lines,are significant for the functional-ity of an electric transmission system.Bolt joint loosening is one of the critical factors that can affect the safety and stability of transmission towers.In this study,the effects of bolt joint loosening on the dynamic characteristics of a 220-kV angle steel transmission tower are the main topic of concern.First,the mechanical properties of typical joints subjected to different degrees of bolt loosening are studied by finite solid-element simulation,based on which a finite hybrid-element modeling method is developed for a tower structure suffering varying loose degrees in the joints.Taking a 220-kV angle steel transmission tower as the object,the influence of the position and degree of loosening on the tower’s natural frequencies and mode shapes are simulated and discussed.The results demonstrate that the main-member splice joint and the main diagonal-horizontal member gusset plate joint account for the dominant impact on the dynamic characteristics of the tower.In addition,the dominant joint shifts from the main-member splice joint to the main diagonal-horizontal member gusset plate joint as the considered modal order increases.In the case of double joints loosening simultaneously,the loosening of nondomi-nant joints has nonnegligible effects on the tower as well. 展开更多
关键词 transmission tower bolt joint bolt loosening dynamic characteristics
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Shear damage constitutive model of rock-like joint surface considering the coupling effect of cyclic water intrusion and loading
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作者 Zhe Qin Runchang Zhang +2 位作者 Ke Wang Lixue Cao Yushui Yan 《International Journal of Mining Science and Technology》 2025年第6期881-895,共15页
Prolonged cyclic water intrusion has progressively developed joints in the hydro-fluctuation belt,elevating the instability risk of reservoir bank slopes.To investigate its impact on joint shear damage evolution,joint... Prolonged cyclic water intrusion has progressively developed joints in the hydro-fluctuation belt,elevating the instability risk of reservoir bank slopes.To investigate its impact on joint shear damage evolution,joint samples were prepared using three representative roughness curves and subjected to direct shear testing following cyclic water intrusion.A shear damage constitutive model considering the coupling effect of cyclic water intrusion and load was developed based on macroscopic phenomenological damage mechanics and micro-statistical theory.Results indicate:(1)All critical shear mechanical parameters(including peak shear strength,shear stiffness,basic friction angle,and joint compressive strength)exhibit progressive deterioration with increasing water intrusion cycles;(2)Model validation through experimental curve comparisons confirms its reliability.The model demonstrates that intensified water intrusion cycles reduce key mechanical indices,inducing a brittle-to-ductile transition in joint surface deformation—a behavior consistent with experimental observations;(3)Damage under cyclic water intrusion and load coupling follows an S-shaped trend,divided into stabilization(water-dominated stage),development(load-dominated stage),and completion stages.The research provides valuable insights for stability studies,such as similar model experiments for reservoir bank slopes and other water-related projects. 展开更多
关键词 Rock joint Cyclic water intrusion Direct shear test Constitutive model Damage evolution Rock-like material
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Acute Single and Joint Toxicity Effects of Imidacloprid and Thiamethoxam on Zebrafish ( Danio Rerio )
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作者 Agnes Adu-Gyamfi Mingxiao LI +1 位作者 Shunlong MENG Xi CHEN 《Agricultural Biotechnology》 2025年第3期36-39,共4页
This study attempted to assess the lethal concentration(96-h LC_(50))effects of imidacloprid(neonicotinoid pesticide),thiamethoxam(neonicotinoid pesticide),and their combination on juvenile Zebrafish(Danio rerio).Each... This study attempted to assess the lethal concentration(96-h LC_(50))effects of imidacloprid(neonicotinoid pesticide),thiamethoxam(neonicotinoid pesticide),and their combination on juvenile Zebrafish(Danio rerio).Each set of trials contained a control(de-chlorinated tap water),and the experiments were repeated three times.The fish(n=10)were randomly measured with an average length of(3.4±0.34)cm and weight of(1±0.1)g.The temperature was kept at 24℃.Experiments 1 and 2 were designed to investigate at the acute toxicity of imidacloprid and thiamethoxam on juvenile zebrafish(Danio rerio)respectively,whereas experiment 3 was aimed at the combined toxicity of IMI and THM on zebrafish.The tests followed the same study design,and each experiment used seven different logarithmic concentrations of imidacloprid insecticides(310.00,317.08,324.33,331.74,339.32,347.07,355.00 mg/L)and thiamethoxam(175.00,185.52,200.93,215.30,230.70,247.20,264.88 mg/L).The results show that THM is more toxic than IMI,with LC_(50)values of 190.34 mg/L for THM and 310.92 mg/L for IMI.Both individual toxicities showed a substantial positive connection(P<0.05)with confidence limits of 321.50-300.68 mg/L for IMI and 199.91-181.21 mg/L for THM.The joint toxicity test was carried out using the 96-h LC_(50)values of imidacloprid and thiamethoxam obtained in the individual acute toxicity trials at a 1:1 ratio.The Additive Index(AI)demonstrated that imidacloprid and thiamethoxam acted synergistically on D.rerio.As a matter of fact,more research is needed to better understand the impact of IMI and THM on other aquatic organisms and also create strategies to mitigate its harmful effects on aquatic life. 展开更多
关键词 Acute toxicity(LC_(50)) joint toxicity IMIDACLOPRID THIAMETHOXAM Zebrafish(Danio rerio)
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Optimized joint repair effects on damage evolution and arching mechanism of CRTS II slab track under extreme thermal conditions
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作者 CAI Xiao-pei CHEN Ze-lin +3 位作者 CHEN Bo-jing ZHONG Yang-long ZHOU Rui HUANG Yi-chen 《Journal of Central South University》 2025年第6期2273-2287,共15页
To address the issue of extreme thermal-induced arching in CRTS II slab tracks due to joint damage,an optimized joint repair model was proposed.First,the formula for calculating the safe temperature rise of the track ... To address the issue of extreme thermal-induced arching in CRTS II slab tracks due to joint damage,an optimized joint repair model was proposed.First,the formula for calculating the safe temperature rise of the track was derived based on the principle of stationary potential energy.Considering interlayer evolution and structural crack propagation,an optimized joint repair model for the track was established and validated.Subsequently,the impact of joint repair on track damage and arch stability under extreme temperatures was studied,and a comprehensive evaluation of the feasibility of joint repair and the evolution of damage after repair was conducted.The results show that after the joint repair,the temperature rise of the initial damage of the track structure can be increased by 11℃.Under the most unfavorable heating load with a superimposed temperature gradient,the maximum stiffness degradation index SDEG in the track structure is reduced by about 81.16%following joint repair.The joint repair process could effectively reduce the deformation of the slab arching under high temperatures,resulting in a reduction of 93.96%in upward arching deformation.After repair,with the damage to interfacing shear strength,the track arch increases by 2.616 mm. 展开更多
关键词 CRTS II slab track optimized joint repair arching mechanism temperature load damage initiation and evolution
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Effect of Artificial Hip Replacement Surgery on the Treatment of Intertrochanteric Femur Fractures in Elderly Patients and Its Impact on Hip Joint Function and Quality of Life
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作者 Yong Qin Jianfei Xu +1 位作者 Dongqian Feng Bin Zhang 《Journal of Clinical and Nursing Research》 2025年第1期88-93,共6页
Objective:To evaluate the treatment effect of total hip arthroplasty(THA)for intertrochanteric femur fractures(IFF)in elderly patients.Methods:Thirty-two elderly patients with IFF admitted to the hospital from August ... Objective:To evaluate the treatment effect of total hip arthroplasty(THA)for intertrochanteric femur fractures(IFF)in elderly patients.Methods:Thirty-two elderly patients with IFF admitted to the hospital from August 2021 to August 2024 were selected and randomly divided into two groups using a random number table.The experimental group(16 patients)underwent THA surgery,while the control group(16 patients)underwent proximal femoral nail antirotation(PFNA)surgery.Hip joint function and quality of life indicators were compared between the two groups.Results:Before surgery,there was no significant difference in hip joint function and quality of life scores between the two groups(P>0.05).However,at six months postoperatively,the experimental group had higher hip joint function and quality of life scores compared to the control group(P<0.05).The total effective rate was higher in the experimental group than in the control group(P<0.05).The complication rate in the experimental group was similar to that in the control group(P>0.05).Conclusion:THA can improve the clinical efficacy of elderly patients with IFF,minimize postoperative complications,effectively restore hip joint function,and optimize postoperative quality of life. 展开更多
关键词 Artificial hip replacement surgery Intertrochanteric femur fractures Elderly patients Hip joint function Quality of life
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Joint Effect of Multiple Air Pollutant Exposure on Dyslipidemia in Chinese Primary School Children
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作者 Yuanduo Zhu Yingying Han +1 位作者 Dandan Li Yanlong Xu 《Biomedical and Environmental Sciences》 2025年第10期1302-1307,共6页
Clean air is fundamental to human health.Approximately 99%of the global population has been exposed to concentrations higher than the World Health Organization’s recommendations.Moreover,adverse health effects have b... Clean air is fundamental to human health.Approximately 99%of the global population has been exposed to concentrations higher than the World Health Organization’s recommendations.Moreover,adverse health effects have been observed at much lower pollution levels than previously studied.China has experienced periods of severe air pollution over the past few decades.To improve air quality and safeguard public health,the government has implemented several progressively tightened policies.Emission control policies were first proposed in 2005. 展开更多
关键词 health effects emission control policies air pollution primary school children China control policies DYSLIPIDEMIA air quality
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Research on the path of effective management of participation in joint-venture railway companies by China railway group 被引量:1
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作者 Shaoni Zhou Zhitian Zhou Chenxia Kang 《Railway Sciences》 2024年第4期530-539,共10页
Purpose-Following the regional restructuring,the number of joint-venture railway companies in which the Group participates has significantly increased.This paper aims to explore the challenges faced by China Railway G... Purpose-Following the regional restructuring,the number of joint-venture railway companies in which the Group participates has significantly increased.This paper aims to explore the challenges faced by China Railway Group in managing participation in joint-venture railway companies.The study seeks to propose specific approaches to ensure the effective management of these companies,thereby maximizing the benefits of the regional restructuring and supporting the development of a strong transportation country and a modern infrastructure system.Design/methodology/approach-Based on the change in the shareholding relationship between China Railway Group and the joint-venture railway companies,and considering the current situation of the regional restructuring of these companies,as well as the insights from existing literature and typical case studies,this paper proposes some specific paths for effective management of joint-stock railway companies which China Railway Group participated in.Findings-The problems in participation management are the unclear dual leadership role of the party committee,the lack of discourse power,the lack of synergy between shareholders,the increasing risk of sustainable operation of the loss-making companies and the role of dispatched personnel is not fully played.Based on the theories,combined with the existing research and practical cases,the paper proposed specific approaches,such as perfecting top-level system design,maintaining the discourse power,carrying out differentiated management,arranging personnel rationally,arranging shareholders synergy,and innovating methods to provide references for China Railway Group’s subsequent management of joint venture railway companies.Originality/value-This paper contributes to the existing literature by providing a comprehensive analysis of the challenges faced by China Railway Group in managing participation in joint-venture railway companies following the regional restructuring.The study offers novel insights and practical recommendations for addressing these challenges.The findings can serve as valuable references for China Railway Group’s subsequent management of joint-venture railway companies which participated in,as well as for other stateowned enterprises facing similar challenges in managing their joint ventures. 展开更多
关键词 China railway group joint venture railway companies Participated relationship effective management
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A review of extreme condition effects on solder joint reliability:Understanding failure mechanisms 被引量:2
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作者 Norliza Ismail Wan Yusmawati Wan Yusoff +2 位作者 Azuraida Amat Nor Azlian Abdul Manaf Nurazlin Ahmad 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第11期134-158,共25页
Solder joint,crucial component in electronic systems,face significant challenges when exposed to extreme conditions during applications.The solder joint reliability involving microstructure and mechanical properties w... Solder joint,crucial component in electronic systems,face significant challenges when exposed to extreme conditions during applications.The solder joint reliability involving microstructure and mechanical properties will be affected by extreme conditions.Understanding the behaviour of solder joints under extreme conditions is vital to determine the durability and reliability of solder joint.This review paper aims to comprehensively explore the underlying failure mechanism affecting solder joint reliability under extreme conditions.This study covers an in-depth analysis of effect extreme temperature,mechanical stress,and radiation conditions towards solder joint.Impact of each condition to the microstructure including solder matrix and intermetallic compound layer,and mechanical properties such as fatigue,shear strength,creep,and hardness was thoroughly discussed.The failure mechanisms were illustrated in graphical diagrams to ensure clarity and understanding.Furthermore,the paper highlighted mitigation strategies that enhancing solder joint reliability under challenging operating conditions.The findings offer valuable guidance for researchers,engineers,and practitioners involved in electronics,engineering,and related fields,fostering advancements in solder joint reliability and performance. 展开更多
关键词 Solder joint Extreme condition Failure mechanism Defence and military RELIABILITY
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Effect of intermittent joint distribution on the mechanical and acoustic behavior of rock masses 被引量:1
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作者 Shuaiyang Fu Haibo Li +2 位作者 Liwang Liu Di Wu Ben Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1231-1244,共14页
The mechanical characteristics and acoustic behavior of rock masses are greatly influenced by stochastic joints.In this study,numerical models of rock masses incorporating intermittent joints with different numbers an... The mechanical characteristics and acoustic behavior of rock masses are greatly influenced by stochastic joints.In this study,numerical models of rock masses incorporating intermittent joints with different numbers and dip angles were produced using the finite element method(FEM)with the intrinsic cohesive zone model(ICZM).Then,the uniaxial compressive and wave propagation simulations were performed.The results indicate that the joint number and dip angle can affect the mechanical and acoustic properties of the models.The uniaxial compressive strength(UCS)and wave velocity of rock masses decrease monotonically as the joint number increases.However,the wave velocity grows monotonically as the joint dip angle increases.When the joint dip angle is 45°–60°,the UCS of the rock mass is lower than that of other dip angles.The wave velocity parallel to the joints is greater than that perpendicular to the joints.When the dip angle of joints remains unchanged,the UCS and wave velocity are positively related.When the joint dip angle increases,the variation amplitude of the UCS regarding the wave velocity increases.To reveal the effect of the joint distribution on the velocity,a theoretical model was also proposed.According to the theoretical wave velocity,the change in wave velocity of models with various joint numbers and dip angles was consistent with the simulation results.Furthermore,a theoretical indicator(i.e.fabric tensor)was adopted to analyze the variation of the wave velocity and UCS. 展开更多
关键词 Stochastic joints Intrinsic cohesive zone model Uniaxial compressive strength(UCS) Wave propagation Fabric tensor
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Microstructure evolution and mechanical properties of brazing joint for ultra-thin-walled Inconel 718 considering grain size effect and brazing temperature 被引量:1
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作者 Rui ZHAO Yueshuai SONG +1 位作者 Hui KANG Min WAN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第2期541-556,共16页
The systematic investigation of the mechanical properties and microstructure evolution process of ultra-thin-walled Inconel 718 capillary brazing joints is of great significance because of the exceptionally high deman... The systematic investigation of the mechanical properties and microstructure evolution process of ultra-thin-walled Inconel 718 capillary brazing joints is of great significance because of the exceptionally high demands on its application.To achieve this objective,this study investigates the impact of three distinct brazing temperatures and five typical grain sizes on the brazed joints’mechanical properties and microstructure evolution process.Microstructural evolution analysis was conducted based on Electron Back Scatter Diffraction(EBSD),Scanning Electron Microscopy(SEM),X-Ray Diffraction(XRD),High-Resolution Transmission Electron Microscopy(HRTEM),and Focused Ion Beam(FIB).Besides,the mechanical properties and fracture behavior were studied based on the uniaxial tension tests and in-situ tension tests.The findings reveal that the brazing joint’s strength is higher for the fine-grain capillary than the coarse-grain one,primarily due to the formation of a dense branch structure composed of G-phase in the brazing seam.The effects of grain size,such as pinning and splitting,are amplified at higher brazing temperatures.Additionally,micro-cracks initiate around brittle intermetallic compounds and propagate through the eutectic zone,leading to a cleavage fracture mode.The fracture stress of fine-grain specimens is higher than that of coarse-grain due to the complex micro-crack path.Therefore,this study contributes significantly to the literature by highlighting the crucial impact of grain size on the brazing properties of ultra-thin-walled Inconel 718 structures. 展开更多
关键词 EYWORDS Ultra-thin-walled structure BRAZING Inconel 718 Grain size effect Brazing temperature
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Effect of weight-adjusted antimicrobial antibiotic prophylaxis on postoperative dosage and surgical site infection incidence in total joint arthroplasty 被引量:1
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作者 Ashim Gupta Vijay Kumar Jain 《World Journal of Orthopedics》 2024年第4期318-320,共3页
Surgical site infections(SSI)following total joint arthroplasty pose a significant concern for both providers and patients across the globe.Currently,administration of antimicrobial antibiotic prophylaxis is used thro... Surgical site infections(SSI)following total joint arthroplasty pose a significant concern for both providers and patients across the globe.Currently,administration of antimicrobial antibiotic prophylaxis is used throughout the world to reduce the incidence of SSI.However,the correct dosage and frequency of administration remains debatable.In this editorial,we emphasized the determination of the effect of administration of weight-adjusted antimicrobial antibiotic prophylaxis regime on the incidence of SSI and postoperative dosage reduction compared to the conventionally used regime during total joint arthroplasty.The results demonstrated similar efficacy between both regimes with respect to the incidence of SSI.In addition,weight-adjustment led to reduced postoperative dosage and has the potential to reduce chances of achieving lower therapeutic concentration,drug resistance,drug toxicity,and costs. 展开更多
关键词 ANTIBIOTICS Antimicrobial prophylaxis Weight-adjusted Surgical site infections Total joint arthroplasty Knee arthroplasty Hip arthroplasty
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A comprehensive review of radiation effects on solder alloys and solder joints
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作者 Norliza Ismail Wan Yusmawati Wan Yusoff +3 位作者 Nor Azlian Abdul Manaf Azuraida Amat Nurazlin Ahmad Emee Marina Salleh 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期86-102,共17页
In the realm of military and defence applications, exposure to radiation significantly challenges the performance and reliability of solder alloys and joints in electronic systems. This comprehensive review examines r... In the realm of military and defence applications, exposure to radiation significantly challenges the performance and reliability of solder alloys and joints in electronic systems. This comprehensive review examines radiation-induced effects on solder alloys and solder joints in terms of microstructure and mechanical properties. In this paper, we evaluate the existing literature, including experimental studies and fundamental theory, to provide a comprehensive overview of the behavior of solder materials under radiation. A review of the literature highlights key mechanisms that contribute to radiation-induced changes in the microstructure, such as the formation of intermetallic compounds, grain growth,micro-voids and micro-cracks. Radiation is explored as a factor influencing solder alloy hardness,strength, fatigue and ductility. Moreover, the review addresses the challenges and limitations inherent in studying the effects of radiation on solder materials and offers recommendations for future research. It is crucial to understand radiation-induced effects on solder performance to design robust and radiationresistant electronic systems. A review of radiation effects on solder materials and their applications in electronics serves as a valuable resource for researchers, engineers, and practitioners in that field. 展开更多
关键词 Defence technology Solder alloy Solder joints Radiation-induced effect MICROSTRUCTURE Mechanical properties
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Effect of continuous nursing on rehabilitation of older patients with joint replacement after discharge
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作者 Xiao-Yan Qi Hong-Yan Zhou Yu-Hong Xing 《World Journal of Clinical Cases》 SCIE 2024年第21期4558-4565,共8页
BACKGROUND Joint replacement is a common treatment for older patients with high incidences of hip joint diseases.However,postoperative recovery is slow and complications are common,which reduces surgical effectiveness... BACKGROUND Joint replacement is a common treatment for older patients with high incidences of hip joint diseases.However,postoperative recovery is slow and complications are common,which reduces surgical effectiveness.Therefore,patients require long-term,high-quality,and effective nursing interventions to promote rehabilitation.Continuity of care has been used successfully in other diseases;however,little research has been conducted on older patients who have undergone hip replacement.AIM To explore the clinical effect of continuous nursing on rehabilitation after discharge of older individuals who have undergone joint replacement.METHODS A retrospective analysis was performed on the clinical data of 113 elderly patients.Patients receiving routine nursing were included in the convention group(n=60),and those receiving continuous nursing,according to various methods,were included in the continuation group(n=53).Harris score,short form 36(SF-36)score,complication rate,and readmission rate were compared between the convention and continuation groups.RESULTS After discharge,Harris and SF-36 scores of the continuation group were higher than those of the convention group.The Harris and SF-36 scores of the two groups showed an increasing trend with time,and there was an interaction effect between group and time(Harris score:F_(intergroup effect)=376.500,F_(time effect)=20.090,Finteraction effect=4.824;SF-36 score:F_(intergroup effect)=236.200,Ftime effect=16.710,Finteraction effect=5.584;all P<0.05).Furthermore,the total complication and readmission rates in the continuation group were lower(P<0.05).CONCLUSION Continuous nursing could significantly improve hip function and quality of life in older patients after joint replacement and reduce the incidence of complications and readmission rates. 展开更多
关键词 Continuous nursing DISCHARGE Older adults joint replacement REHABILITATION effect
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Ozone Injections in Orthopaedics: An Effective Substitute for Cortisone Injections in Total Joint Replacement Patients and Other Arthritic Conditions 被引量:1
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作者 Frederick F. Buechel 《Open Journal of Orthopedics》 2024年第12期555-561,共7页
Background: Total joint replacement (TJR) patients can suffer from tendinitis, bursitis or other inflammatory conditions that are generally treated by cortisone (corticosteroid) injections. Such injections rarely caus... Background: Total joint replacement (TJR) patients can suffer from tendinitis, bursitis or other inflammatory conditions that are generally treated by cortisone (corticosteroid) injections. Such injections rarely cause complications in the general public, but have resulted in severe implant infections in some patients with joint replacements. The purpose of this study is to review the literature involving joint replacement infections after cortisone injections and present ozone as an alternative to cortisone in a series of joint replacement patients with periarticular inflammatory conditions. Methods: There were 26 combined patients with either total hip replacement (THR), total knee replacement (TKR), total ankle replacement (TAR), or resurfacing shoulder replacement (SR) that developed tendonitis, bursitis or inflammatory problems related to their respective joint arthroplasties. Rather than use cortisone, they were given prolozone injections into the inflammatory regions to relieve them of their pain and dysfunction. This injection was followed by an ice pack for one hour and a return to normal function thereafter. Results: All THR, TKR, SR and TAR pathologies were improved or asymptomatic after one or a series of prolozone injections into the area of inflammation. No cortisone injections were used and no infections were encountered. Conclusions: Prolozone injection therapy is an effective treatment for post-operative inflammatory conditions following total joint replacement. Patients find relief of inflammation symptoms, similar to steroid injections, without the risk of infection or tissue breakdown. Prolozone injection therapy can be useful when conventional injection treatment fails, or is contraindicated. 展开更多
关键词 Ozone Gas Prolozone Injections Total joint Infections Cortisone Associated Infections
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