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Carbon Fiber from Biomass Sources:A Comprehensive Review

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Non-Metallic Material Science 2023年第1期5卷 14-26页

作者： md.Touhidul Islam md.Shahin Howlader Din Mohamad Shuvo md.Kamal uddin Department of Textile Engineering Mawlana Bhashani Science and Technology UniversityTangailDhaka1902Bangladesh

Global energy demand is rising,fossil fuel prices are rising,fossil fuel reserves are running out,and fossil fuel use contributes to the greenhouse *** a clean alternative source of energy to fossil fuels,biomass is becoming more and more *** fiber(CF),often known as graphite fiber,is a thin,strong,and adaptable material utilized in both structural(capacity)and non-structural applications(e.g.,thermal insulation).Precursors are the raw materials used to create carbon fiber,which is mostly derived from fossil *** of the high cost of precursors and manufacture,carbon fiber has only found employment in a few numbers of high-performance structural materials(e.g.,aerospace).To reduce the price of CF and reliance on fossil fuels,numerous alternative precursors have been studied throughout the years,including biomass-derived precursors such as rayon,lignin,glycerol,and lignocellulosic *** study’s goal is to present a detailed study of biomass-derived CF precursors and their market *** authors look into the viability of producing CF from these precursors,as well as the state of technology,potential applications,and cost of production(when data are available).We go over their benefits and *** also talk about the physical characteristics of CF made from biomass and contrast them with CF made from polyacrylonitrile(PAN).Additionally,we go into bio-based CF manufacturing and end-product concerns,logistics for biomass feedstock and plant sites,feedstock competition,and risk-reduction *** paper offers a comprehensive overview of the CF potential from all biomass sources and can be used as a resource by both novice and seasoned professionals who are interested in producing CF from non-traditional sources.

关键词： Carbon fibre Polyacrylonitrile Biomass Lignocellulosic

A Survey on Matching of Shoeprint with Reference Footwear in Forensic Study

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Journal of Computer and Communications 2019年第9期7卷 19-26页

作者： md. Al Mamun Morium Akter Mohammad Shorif uddin Department of Computer Science and Engineering Jahangirnagar University Savar Bangladesh

Footwear impression marks on the outside surface of shoes are distinctive patterns and an important forensic clue often found at offense scenes. However, in many cases, the footwear mark is treated with improper evidence due to difficulties in visibility and understanding. This paper presents a thorough review of matching algorithms along with enhancement techniques of shoeprint in the forensic study. Finally, it shows some research directions.

关键词： Forensic Study Footwear Shoeprint Feature Extraction Segmentation

A Time Dependent Inventory Model for Exponential Demand Rate with Constant Production Where Shelf-Life of the Product Is Finite

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Open Journal of Applied Sciences 2016年第1期6卷 38-48页

作者： Mohammad Ekramol Islam Shirajul Islam Ukil md. Sharif uddin Department of Business Administration Northern University Dhaka Bangladesh Department of Mathematics Jahangirnagar University Savar Bangladesh

In this paper a time dependent inventory model is developed on the basis of constant production rate and market demands which are exponentially decreasing. It advances in quest of total average optimum cost considering those products which have finite shelf-life. The model also considers the small amount of decay. Without having any sort of backlogs, production starts. Reaching at the desired level of inventories, it stops production. After that due to demands along with the deterioration of the items it initiates its depletion and after certain periods the inventory gets zero. The decay of the products is level dependent. The objective of this paper is to find out the optimum inventory cost and optimum time cycle. The model has also been justified with proving the convex property and by giving a numerical example.

关键词： Production Inventory Shelf-Life Time Dependent Demand Class Production Rate

Post Thyroidectomy Assessment of Intact Parathyroid Hormone for Early Prediction of Hypocalcaemia

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International Journal of Otolaryngology and Head & Neck Surgery 2024年第2期13卷 71-84页

作者： md. Masum Billah Ripon Kumar Sarkar md. Yousuf Ali Saad Zaman md. Nazmul Hasan md. Shehab uddin md. Mosleh uddin Kazi Shameemus Salam Farzana Binte Abedin Leera Department of Otolaryngology-Head & Neck Surgery Universal Medical College Hospital Dhaka Bangladesh Department of Otolaryngology-Head & Neck Surgery National Institute of Ear Nose and Throat Dhaka Bangladesh Shaheed Ahsan Ullah Master General Hospital Gazipur Bangladesh Department of Otolaryngology-Head & Neck Surgery Cumilla Medical College Cumilla Bangladesh Department of ENT Oncology National Institute of Cancer Research & Hospital Dhaka Bangladesh Department of ENT Outdoor Rajshahi Medical College Hospital Rajshahi Bangladesh Department of Otolaryngology-Head & Neck Surgery Bangabandhu Sheikh Mujib Medical University Dhaka Bangladesh Department of Biochemistry Delta Medical College Hospital Dhaka Bangladesh

Background: As the half-life of intact parathyroid hormone (iPTH) is very low, it reflects parathyroid insufficiency within minutes to hours after total thyroidectomy. Therefore, iPTH level assessment in the postoperative period can be used to predict the development of hypocalcaemia. The optimal time point to measure serum iPTH is important for the accurate prediction of hypocalcaemia. Aim: This paper aims to evaluate the ability of iPTH as an early predictive marker of hypocalcaemia and determine which time iPTH is more able to predict postoperative hypocalcaemia. Method: This prospective observational study was conducted in the Department of Otolaryngology-Head & Neck Surgery, BSMMU, Dhaka, from July 2020 to December 2021, with 67 patients who underwent total thyroidectomy. iPTH levels were measured on the day before the operation and at 1 hour, 4 hours, and 24 hours after the operation. *** levels were measured on the day before the operation and 1st postoperative day. All the data were compiled and sorted properly and were analyzed statistically. Results: Postoperative hypocalcaemia developed in 18 cases, with an incidence of 26.9%. Pearson correlation showed a significant correlation between postoperative iPTH at 1 hr, 4 h, and 24 hr with 1st postoperative calcium value. The Receiver operating characteristic (ROC) curve was processed for the postoperative iPTH at 1 hr, 4 h, and 24 hr. The sensitivity, specificity, cut-off value, and mean AUC found 93.9%, 94.4%, ≤14.0, 0.988;95.9%, 94.4%, ≤09.5, 0.993 and 91.8%, 94.4%, ≤11.0, 0.993 respectively. Conclusion: iPTH can be used as an early predictor of post-thy-roidectomy hypocalcaemia. 4 hr iPTH showed more sensitivity and specificity for a cut-off value near the laboratory reference range.

关键词： Total Thyroidectomy Hypocalcaemia Serum Intact Parathyroid Hormone Early Predictor of Hypocalcaemia

Experimental and analytical assessment of the hypervelocity impact damage of GLAss fiber REinforced aluminum

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Defence Technology（防务技术） 2022年第7期18卷 1232-1246页

作者： md.Zahid Hasan Bangladesh Air Force Academy Bangladesh Air Force Base Matiur RahmanBAF Academy Road7404 JessoreKhulnaBangladesh

This article addresses the response of GLAss fiber REinforced aluminum to hypervelocity impacts of micrometeoroid analogs at impact velocities of 7 km/s and *** relation,the damage modes of different GLAss fiber REinforced aluminum configurations have been *** GLAss fiber REinforced aluminum configurations comprised six to twelve variably thick aluminum layers and up to four plies of glass fiber reinforced epoxy per composite *** impact experiments have been conducted with the help of a two-stage light-gas gun,wherein aluminum-and stainless steel projectiles were launched at velocities up to 7.15 km/*** inspection of the damage area suggested the dissipation of impact energy in elastic-plastic deformation,petalling,delamination,debonding,tensile failure of fibers,and pyrolysis of epoxy.A prevailing damage mode was not apparent *** quasi-isotropic ply orientation of S2-glass/FM94-epoxy laminates promoted the interference of shockand rarefaction waves and suppressed the damage area of GLAss fiber REinforced *** discriminate between the impact performance of different GLAss fiber REinforced aluminum configurations,the energy dissipated in different damage modes of GLAss fiber REinforced aluminum has been assessed *** terms of normalized energy,the cross-ply GLAss fiber REinforced aluminum dissipated higher energy in petal formation than in other primary damage *** normalized petalling energy was found to decline with the increase of impact *** outcomes of this study will help to optimize the GLAss fiber REinforced aluminum laminate,which will be employed as a bumper shield to prevent the fatal damage and the unzipping of a spacecraft pressure bulkhead.

关键词： Hypervelocity impact Petalling Fiber failure Volumetric compression Sublimation of epoxy

香蕉组织培养过程中内生菌污染的控制(英文)

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生物工程学报 2007年第6期23卷 1042-1048页

作者： Soubir Titov Salil Kumar Bhowmik md.Sadrul Alam Sarder Nasir uddin Biotechnology and Genetic Engineering Discipline Khulna University Biotechnology Department Bangladesh Agricultural University

研究了体外培养一种孟加拉传统香蕉（Musa ***）的茎尖组织。茎尖的原始细胞表面经无菌处理（0．1％HgCl2处理12min），接种6～15d后外植体地下茎部分仍有微生物污染（大部分是细菌），杀死了85％的外植体。为确定无污染培养基，将等量... 详细信息

研究了体外培养一种孟加拉传统香蕉（Musa ***）的茎尖组织。茎尖的原始细胞表面经无菌处理（0．1％HgCl2处理12min），接种6～15d后外植体地下茎部分仍有微生物污染（大部分是细菌），杀死了85％的外植体。为确定无污染培养基，将等量外植体分别浸泡在舍400mg／L氨苄青霉素和200mg／L庆大霉素（两种光谱抗生素）的培养基中1h。结果表明，经抗生素处理的外植体完全没有污染，但培养3周后不能再生。进行二次继代培养后，其中一部分外植体吸收了培养基并胀大，颜色由苍白转变成浅绿或深绿。三次继代培养后数天，不再观察到外植体的生长，所有经抗生素处理过的外植体都开始死亡。在未经抗生素处理的活外植体中，单个茎发育的最佳培养基是：Ms＋4．0mg／LBA＋0．5mg/L KT＋15％CW，平均生长时间为18～21d，但再生率很低，只有30％。茎细胞增殖的最佳培养基是：MS＋4．0mg／L BA＋2．0mg／L IAA＋15％CW，每个茎平均只萌发3～4个芽。最后，在添加0．5mg／L IBA的一半浓度的MS培养基中，体外培养茎最大生根率达到90％。

关键词：香蕉 Kanthali 体外茎尖抗生素

Behaviour of self-centring shear walls——A state of the art review

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Frontiers of Structural and Civil Engineering 2023年第1期17卷 53-77页

作者： Mehdi JAVADI Reza HASSANLI md Mizanur RAHMAN md Rajibul KARIM UniSA STEM University of South AustraliaAdelaide 5095Australia

The application of unbonded post-tensioning (PT) in structural walls has led to the development of advanced self-centring (rocking) shear wall systems that has significant advantages, including accelerated construction due to the incorporation of prefabricated elements and segmental construction for different materials (e.g., concrete, masonry, and timber), reduced residual drifts, and little damage upon extreme seismic and wind loads. Concrete, masonry, and timber are often used for the construction of unbonded PT structural wall systems. Despite extensive research since the 1980s, there are no well-established design guidelines available on the shear wall configuration with the required energy dissipation system, joint’s locations and acceptance criteria for shear sliding, confinement, seismic performance factors, PT loss, PT force range and residual drifts of shear walls subjected to lateral loads. In this research a comprehensive state-of-the-art literature review was performed on self-centring shear wall system. An extensive study was carried out to collect a database of 100 concrete, masonry, and self-centring shear wall tests from the literature. The established database was then used to review shear walls’ configurations, material, and components to benchmark requirements applicable for design purposes. The behaviour of concrete, masonry and timber shear walls were compared and critically analysed. The general behaviour, force-displacement performance of the walls, ductility, and seismic response factors, were critically reviewed and analysed for different self-centring wall systems to understand the effect of different parameters including configurations of the walls, material used for construction of the wall (concrete, masonry, timber) and axial stress ratio. The outcome of this research can be used to better understand the behaviour of self-centring wall system in order to develop design guidelines for such walls.

关键词： self-centring shear walls rocking walls energy dissipation seismic performance factors PT loss residual drift

Morphological and Genetical Variability among Rhizoctonia solani Isolates Causing Sheath Blight Disease of Rice

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Rice science 2016年第1期23卷 42-50页

作者： Zakiah Rahman MONI md Ansar ALI md Shahidul ALAM md Asif RAHMAN md Rejwan BHUIYAN md Salim MIAN Khandakar md IFTEKHARUDDAULA md Abdul LATIF Mohammad Ashik Iqbal KHAN Plant Breeding Division Bangladesh Rice Research Institute Director Research Bangladesh Rice Research Institute Department of Botany Rajshahi University Department of Genetics and Plant Breeding Bangabandhu Sheikh Mujibur Rahman Agricultural University Plant Pathology Division Bangladesh Rice Research Institute

Eighteen isolates of Rhizoctonia solani collected from infected rice plants in four different locations of Bangladesh were studied by using morphological characters and molecular markers. Anastomosis study with a reference isolate confirmed that all the isolates belonged to R. solani. Significant variation was observed in sclerotial size, shape and distribution. Un-weighted pair group method with arithmetic mean dendrogram constructed based on the Gower＇s general similarity coefficient showed that these isolates were grouped into four clusters at the 0.68 similarity coefficent according to morphological characters. Cluster I was a major cluster consisting of 13 isolates, while clusters Ⅱ to Ⅳ consisted of 1 or 2 isolates. Analyses by variable number of tandem repeat and amplified fragment length polymorphism markers showed that the isolates were grouped into five and three clusters at a similarity coefficient of 0.64 and 0.69, respectively. Although most of the variability was found between isolates from different regions as expected, significant variation was observed within the isolates collected from similar agro-ecological regions. Our results suggest the presence of different races of R. solani within the same local geographic regions.

关键词： rice Rhizoctonia solani fungal variability molecular marker morphological character

Minimization of Air Consumption and Potential Savings of Textile Denim Fabric Manufacturing Process

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Journal of Textile Science and Technology 2023年第1期9卷 69-83页

作者： md. Enamul Haque md. Bokthier Rahman Waliul Kafi md. Suja uddin Kaiser Abhijit Dey Khulna University of Engineering & Technology (KUET) Khulna Bangladesh Bangladesh University of Textiles (BUTEX) Dhaka Bangladesh

One of the most important aspects of Bangladesh’s textile industry is denim. Bangladesh now has a new opportunity thanks to the global demand for denim among fashion industry professionals. Entrepreneurs from Bangladesh provide denim products to well-known international merchants all over the world. The worldwide denim market is predicted to expand by roughly 8% through the year 2020. We must raise the standard of denim if we are to keep up with the expanding industry. In contrast to projectile and rapier systems, air-jet weaving machines nowadays can weave practically all types of yarns without any issues and at higher rates. Due to this, air-jet looms are an excellent substitute for other weft insertion techniques. This kind of device still has one significant flaw, though, and that is the enormous power consumption brought on by the creation of compressed air. Researchers and manufacturers of air-jet looms have therefore worked very hard to find a solution to this issue and achieve a huge reduction in air consumption without compromising loom performance or fabric quality. Therefore, the purpose of this project is to look into ways to decrease air consumption and reduce auxiliary selvedge waste without any decrease in loom performance and fabric quality on existing air-jet weaving looms which reduce the manufacturing costs with process improvement. Just updating the air pressure allowed a weaving mill to reduce air usage by 11 cfm. So, with just almost no cost, a company with 100 looms could save $0.15 M each year, on compressed air. Two new methods for decreasing process costs on air jet looms have also been developed by this project work.

关键词： Denim Woven Textiles Weaving Machine Air Consumption Cost Reduction Waste Reduction Potential Savings