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不同铜线芯直径超声波焊接头性能的研究

兵器材料科学与工程 2024年

作者：沈中华张永祺赵伦龚涛梁召峰许龙周光平 md shafiqul islam 广西高校先进制造与自动化技术重点实验室深圳职业技术大学超声技术研究所瑞典布京理工学院机械学院

本文对三种不同的线芯直径的10mm2铜（Cu）导线接头进行了超声波焊接试验。通过剥离实验、孔隙率计算、温度测量、扫描电子显微镜(SEM)研究分析了铜导线接头性能和失效形式。结果表明，线芯直径与接头抗剥离力呈正相关，线芯直径越粗接... 详细信息

本文对三种不同的线芯直径的10mm2铜（Cu）导线接头进行了超声波焊接试验。通过剥离实验、孔隙率计算、温度测量、扫描电子显微镜(SEM)研究分析了铜导线接头性能和失效形式。结果表明，线芯直径与接头抗剥离力呈正相关，线芯直径越粗接头力学性能越好。两根线芯直径为0.1 mm导线焊接接头的接头抗剥离强度未达到标准，失效形式表现为结合面完全分离无线芯断裂。直径增加到0.2mm时，接头抗剥离强度均达到标准，失效形式变为结合面处线芯的韧性断裂。焊接时的峰值温度有效影响了接头孔隙率，但孔隙率并不能完全作为判断接头成型质量的依据，部分导线在高温下仅仅发生塑性变形，而未能实现原子键合。此外，通过观察接头剖面发现，焊接接头形成了外紧内松的结构，与压块接触的接头上侧和与焊头接触的接头下侧几乎无空隙，而接头中间内侧则存在大量空隙。

关键词：超声波焊接铜导线力学行为断口形貌

Acute Lymphoblastic Leukemia Presenting as Systemic Juvenile Idiopathic Arthritis: Experience from Bangladesh

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Open Journal of Rheumatology and Autoimmune Diseases 2024年第1期14卷 1-12页

作者： Manik Kumar Talukder Kamrul Laila md. Arif Hossain md. shafiqul islam md. Zahidul islam Kalyan Benjamin Gomes Mujammel Haque md. Mahbubul islam md. Imnul islam Department of Paediatrics Bangabandhu Sheikh Mujib Medical University Dhaka Bangladesh Health Services Dhaka Bangladesh NICVD Dhaka Bangladesh

Background: Acute lymphoblastic leukemia (ALL), the most common paediatric malignancy, is a heterogeneous hematologic disease. ALL patients may present with isolated and persistent osteo-articular complaints, lower incidence of hepatomegaly, splenomegaly or lymphadenopathy without clear laboratory features, and misdiagnosed as systemic juvenile idiopathic arthritis (sJIA). Methods: This was a single center cross sectional study over a period of 4 years. Clinic laboratory profiles of 39 ALL children were compared with 39 age and sex-matched sJIA cases. Result: Among 39 ALL patients 89.7% were initially misdiagnosed as sJIA upon clinical presentation. Majority (66.7%) of ALL patients had oligo-articular joint involvement. In sJIA, small joints of the hands were most commonly involved. The total WBC count was significantly higher in ALL patients (p-value 0.0065). CRP and LDH values between the two groups showed significant differences (p-value 0.00006 and 0.00001 respectively). Conclusion: The presentation of leukemia with arthralgia or arthritis makes the diagnosis difficult for the physicians. The diagnosis of sJIA must be made with caution keeping the possibility of haematological malignancy in mind.

关键词： ALL sJIA Arthritis Arthralgia Musculoskeletal

超声波焊接能量对大直径线束-端子接头性能影响

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应用声学 2024年第4期43卷 799-806页

作者：许龙洪宛璐赵伦李承旺雷乐张溟晨梁召峰周光平 md shafiqul islam 中国计量大学理学院杭州310018 深圳职业技术学院智能制造技术研究院深圳518055 瑞典布京理工学院机械学院卡尔斯克鲁纳37179

线束与端子的连接技术在新能源汽车上的需求日益增大。传统连接方式存在耗能高、性能不稳定、产生污染等缺点,因此超声波焊接技术被推广应用到新能源汽车的线束连接上。该文以EVRP5平方屏蔽高压线为研究对象,采用单一变量法对线束进行... 详细信息

线束与端子的连接技术在新能源汽车上的需求日益增大。传统连接方式存在耗能高、性能不稳定、产生污染等缺点,因此超声波焊接技术被推广应用到新能源汽车的线束连接上。该文以EVRP5平方屏蔽高压线为研究对象,采用单一变量法对线束进行超声波焊接试验,以焊接能量为变量,通过力学性能测试、微观分析和超声波检测分析超声波的焊接机理。试验结果表明,当焊接能量为5 kJ时,接头抗拉力为2616 N;当焊接能量为11 kJ时,接头抗拉力提高至6650 N。在一定范围内,随着焊接能量的不断增大,接头由靠近工具头处和焊接界面处向内,由未连接状态到点连接、线连接、面连接最终逐渐形成原子间键合。

关键词：超声波焊接线束焊接能量力学性能

Source identification, contamination status and health risk assessment of heavy metals from road dusts in Dhaka, Bangladesh

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Journal of Environmental Sciences 2022年第11期34卷 159-174页

作者： Aklima Nargis Ahsan Habib md Nazrul islam Kai Chen md shafiqul islam Sarker A N M Al-Razee Wenbin Liu Guorui Liu Minggang Cai Coastal and Ocean Management Institute&State Key laboratory of Marine Environmental Science Xiamen UniversityXiamen 361005China Department of Chemistry University of DhakaDhaka 1000Bangladesh Central Chemical Laboratory Department of Narcotics ControlMinistry of Home AffairsDhaka 1204Bangladesh Department of Analytical Chemistry&Environmental Science Training Institute for Chemical IndustriesPolashNarsingdi 1611Bangladesh State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

In this study, concentrations of Cr, Mn, Ni, Cu, Zn, Cd and Pb were determined in road dusts collected from different locations in Dhaka to assess source, contamination status and health risk. Energy-dispersive X-ray fluorescence spectroscopy and energy-dispersive X-ray spectroscopy were used to determine Cr, Mn, Ni, Cu, Zn, Cd and Pb and their mean concentrations were 162.27 ± 29.46, 721.18 ± 180.14, 35.65 ± 12.55, 104.56 ± 128.33, 515.32 ± 321.90,BDL, and 342.82 ± 591.20 mg/kg, respectively. Among the heavy metals, highest concentrations of Cu, Zn and Pb were found at urban sites-7(municipal waste dumping) and 8(medical waste incineration). Highest concentration of Cr followed by Cu and Zn was found at site-5(Tejgaon, urban). Principal component analysis revealed that anthropogenic activities are the potential sources for Cr, Ni, Cu, Zn and Pb while earth crust for Mn. Pollution index and pollution load index results suggested that all the sites were contaminated and/or degraded by Cr, Cu, Zn and Pb except sites-9(urban), 10(sub-urban), 11(rural) while sites-7 and 8(urban) were extremely degraded. For noncarcinogenic health risk, hazard quotient values for dermal were higher compared to that of inhalation/ingestion. Though hazard index values were less than 1 at all the sites, these were at least one order of magnitude higher for children group than that of adult group, thus the children group may face more noncarcinogenic health risk at sites -7 and 8. Values of incremental lifetime cancer risk were from 10to 10showed no carcinogenic health risk by road dusts contaminated with the heavy metals.

关键词： Heavy metal Road dust Dhaka Principal component analysis Pollution status Health risk assessment

Anterior Chamber Depth Changes in Narrow Iridocorneal Angles after Phacoemulsification

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Open Journal of Ophthalmology 2023年第2期13卷 187-198页

作者： md. Ariful islam Abir Bin Sajj Tohura Sharmin md. Sanwar Hossain md. shafiqul islam Department of Ophthalmology Combined Military Hospital (CMH) Dhaka Bangladesh Vision Eye Hospital Dhaka Bangladesh Department of Community Medicine Ad-Din Women’s Medical College Dhaka Bangladesh Department of Ophthalmology Dr. Sirajul Islam Medical College & Hospital Dhaka Bangladesh Department of Ophthalmology Bangabandhu Sheikh Mujib Medical University (BSMMU) Dhaka Bangladesh

Background: The burden of cataract and glaucoma has been increasing. Primary angle closure occurs as a result of crowded anterior segment anatomy causing appositional contact between peripheral iris and trabecular meshwork. Lens extraction has been proposed as a method of deepening anterior chamber and managing intraocular pressure. Purpose: To assess changes in anterior chamber depth after phacoemulsification with intraocular lens implantation in narrow angle eyes. Design: Prospective controlled trial (before-after) study. Method: The study was conducted from March 2015 to August 2017 among the patients of department of Ophthalmology of BSMMU who were diagnosed as cataract with narrow angles. Anterior chamber angle grading of 2 or less (Shaffer grading) in 3 or more quadrants was considered narrow angle (NA). The purposive type sampling technique was applied to collect sample from the study population, as per inclusion and exclusion criteria. Complete clinical evaluation including history, physical examination, relevant ocular examinations and systemic examinations were performed. In this prospective study, subjects underwent phacoemulsification with foldable lens implantation. A scan ultrasonography was performed preoperatively and 10th and 30th postoperative days of surgery. Results: Thirty eyes of 29 patients included in the study, male: female ratio was 1:1, with an overall mean age of 62.03 ± 8.95 years. The mean preoperative central ACD was 2.95 ± 0.35 mm. At 10th and 30th POD mean central ACD were 3.94 ± 0.32, and 3.92 ± 0.28 mm respectively. Mean of increase in central ACD at final follow-up was 0.96 mm (p Conclusion: Phacoemulsification with posterior chamber in bag lens implantation can deepen the anterior chamber depth in patients with narrow angles. Based on these findings, it is concluded that phacoemulsification with foldable intraocular lens implantation is an effective tool in deepening the anterior chambe

关键词： Anterior Chamber Depth Phacoemulsification Iridocorneal Angles Open Angle Narrow Angle

Prediction of Turbulent Flow Structure in a Fully Developed Rib-Roughened Narrow Rectangular Channel

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Journal of Thermal Science 2009年第2期18卷 126-136页

作者： md.shafiqul islam M.Kaminaga R.Hino M.Monde Atomic Energy Research Establishment Japan Atomic Energy Agency (JAEA) Department of Mechanical Engineering Saga University

Fully developed turbulent water-flow structure over one-side repeated-ribs in narrow two-dimensional rectangularchannels was investigated experimentally by Particle Image Velocimetry (PIV) and analytically by the standardk-ε and nonlinear k-ε turbulent models. Two rib-pitch to height ratios (p/k) of 10 and 20 were investigated whilethe rib height was held constant at 4 mm. The rib height-to-channel equivalent diameter ratio (k/De) was 0.1. Thestreamwise mean velocity and turbulent kinetic energy distributions at six selected axial stations from the centerrib for the two Reynolds number (Re) of 7,000 and 20,000 were obtained and compared with the predicted *** performance ability in predicting separating and reattaching turbulent water-flow between the standard K-eand nonlinear K-e models had yielded no clear conclusion. A large-scale turbulent eddy was generated by the ribpromoter and then propagated into the mainstream flow, which led to the deformation of the velocity profile. Theturbulent kinetic energy was increased about two times higher at p/k = 20 than that at p/k =10 under the twoReynolds numbers. The effect of the p/k value and the Reynolds number (Re) on reattachment length (XR) wasinvestigated and showed that the p/k and Re had no significant effect on the reattachment length beyond a criticalvalue of Re =15,000 where XR was found to be approximately 4 times of the rib height under water-flow condition.

关键词：湍流矩形通道二相分析再附长度

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铝钛轻合金多种连接工艺力学性能对比

塑性工程学报 2023年第8期30卷 138-145页

作者：李承旺赵伦许龙洪宛璐霍小乐雷乐张溟晨孙可 md shafiqul islam 深圳职业技术学院超声技术研究所广东深圳518055 中国计量大学理学院浙江杭州310018 瑞典布京理工学院机械学院布莱金厄卡尔斯克鲁纳37179

选用5A06铝合金与TA1钛合金进行热熔钻铆、超声压铆和超声自冲铆连接试验。通过静拉伸试验研究了板材搭接方式对各组接头力学性能的影响。结果表明,铆接时软板在上时,热熔钻铆接头与超声自冲铆接头的力学性能显著提高,板材搭接方式对超... 详细信息

选用5A06铝合金与TA1钛合金进行热熔钻铆、超声压铆和超声自冲铆连接试验。通过静拉伸试验研究了板材搭接方式对各组接头力学性能的影响。结果表明,铆接时软板在上时,热熔钻铆接头与超声自冲铆接头的力学性能显著提高,板材搭接方式对超声压铆接头影响较小。热熔钻铆接头具有最佳的缓冲吸震性能,但是稳定性较差,应用于车身结构时较为局限。超声压铆接头成本低且工艺简单,但其抗剪切性能差,不适用于承受大应力的车身结构。与其他两种连接方式相比,超声自冲铆连接稳定性最佳,具有最佳的抗拉伸能力与剪切刚度,适用于车身轻量化领域的大部分结构。

关键词：热熔钻铆超声压铆超声自冲铆铝合金钛合金力学性能

Watering techniques and zero-valent iron biochar pH effects on As and Cd concentrations in rice rhizosphere soils,tissues and yield

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Journal of Environmental Sciences 2021年第2期33卷 144-157页

作者： md shafiqul islam Yali Chen Liping Weng Jie Ma Zulqarnain Haider Khan Zhongbin Liao Abdoul Salam Issiaka Abdoul Magid Yongtao Li Agro-Environmental Protection Institute/Key Laboratory for Environmental Factors Control of Agro Product Quality Safety Ministry of Agriculture and Rural AffairsTianjin 300191China College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642China Chinese Academy of Agricutural Sciences Beijing 100081China Department of Soil Quality Wageningen Universit6700 AAWageningenNetherlands

Zero-valent iron amended biochar(ZVIB)has been proposed as a promising material in immobilizing heavy metals in paddy *** this study,the impacts of p H of ZVIB(p H 6.3 and p H 9.7)and watering management techniques(watering amount in the order of CON(control,5/72)>3/72>1-3/72>3/100>1/72,with 5/72,for example,representing irrigation given to 5 cm above soil surface in 72 hr regular interval)on As and Cd bioavailability for rice and its grain yield(Yield BR)were investigated in a pot *** rice As(As BR)content was irrelative to the watering treatments,while significantly decreased(>50%)with the addition of both ZVIB *** diminutions of brown rice Cd(Cd BR)content as well as the Yield BR were highly dependent on both the soil amendment materials’p H and watering *** all the watering treatments,3/72 treatment(15%less irrigation water than the CON)with ZVIB 6.3 amendment was the optimum fit for simultaneous reduction of As BR(50%)and Cd BR contents(19%)as well as for significant increment(12%)of the Yield *** high pH(9.7)ZVIB application could also efficiently decrease As and Cd contents in brown rice,it might risk grain yield lost if appropriate(e.g.3/72 in our study)watering management technique was not ***,ZVIB would be an environmentally friendly option as an amendment material with proper selection of watering management technique to utilize As and Cd co-contaminated arable soils safely for paddy cultivation.

关键词： Brown rice As Brown rice Cd Grain yield Paddy soils Water management Zero-valent iron biochar

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TA1/5A06同质自冲铆接头的力学性能

锻压技术 2022年第12期47卷 135-141页

作者：郭子鑫赵伦郭媛媛齐晓志刘纪元霍小乐林森 md shafiqul islam 深圳职业技术学院智能制造技术研究院广东深圳518055 辽宁科技大学材料与冶金学院辽宁鞍山114051 中国科学院深圳先进技术研究院集成所广东深圳518055 布京理工学院机械学院瑞典卡尔斯克鲁纳37179

为了进一步研究自冲铆接技术在航空航天领域的应用,选用TA1钛合金和5A06铝合金航空合金薄板材料作为基板,采用自冲铆接技术进行连接,并通过拉伸试验和扫描电镜试验对接头的静力学性能及微观组织进行系统的研究。结果表明:同质接头的成... 详细信息

为了进一步研究自冲铆接技术在航空航天领域的应用,选用TA1钛合金和5A06铝合金航空合金薄板材料作为基板,采用自冲铆接技术进行连接,并通过拉伸试验和扫描电镜试验对接头的静力学性能及微观组织进行系统的研究。结果表明:同质接头的成形对称性良好,铆接较硬板材时易出现空腔;基板的自身性能对接头静载强度的影响较大;5A06-5A06接头的失效位移最大,上板拉脱是由于铆钉周围产生了微裂纹;TA1-TA1接头的静失效载荷最大,缓冲吸震性能较好,其接头铆钉的断裂形式为沿晶断裂和显微孔穴聚集共同作用的混合型断裂。

关键词：自冲铆接钛合金铝合金静载强度缓冲吸震性能微观组织