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Experimental Investigation on the Mechanical Properties of Natural Fiber Reinforced Concrete

Journal of Renewable Materials 2022年第5期10卷 1307-1320页

作者： Ismail Shah Jing Li Shengyuan Yang Yubo Zhang aftab anwar School of Architecture and Civil Engineering Yunnan Agricultural UniversityKunming650000China Key Laboratory of Crop Growth and Intelligent Agriculture of Yunnan Province Yunnan Agricultural UniversityKunming650000China

Recently,addition of various natural fibers to high strength concrete has aroused great interest in the field of building *** is because natural fibers are much cheaper and locally available,as compare to synthetic *** in view,this current research conducted mainly focuses on the static properties of hybridized(sisal/coir),sisal and coir fiber-reinforced *** types of natural fibers sisal and coir were used in the experiment with different lengths of 10,20 and 30 mm and various natural fiber concentrations of 0.5%,1.0%,and 1.5%by mass of cement,to investigate the static properties of sisal fiber reinforced concrete(SFRC),coir fiber reinforced concrete(CFRC)and hybrid fiber reinforced concrete(HFRC).The results indicate that HFRC has increased the compressive strength up to 35.98%with the length of 20 mm and with 0.5%concentration,while the CFRC and SFRC with the length of 10 mm and with 1%concentration have increased the compressive strength up to 33.94%and 24.86%,*** another hand,the split tensile strength was increased by HFRC with the length of 20 mm and with 1%concentration,CFRC with the length of 10 mm and with 1.5%concentration,and SFRC with the length of 30 mm and with 1%concentration have increased up to 25.48%,24.56%and 11.80%,respectively,while the HFRC with the length of 20 mm and with 0.5%concentration has increased the compressive strength of concrete but has decreased the split tensile strength up to 2.28%compared to ***,using the HFRC with the length of 20 mm and with 1%concentration provide the maximum output in terms of split tensile strength.

关键词： Sisal fiber reinforced concrete coir fiber reinforced concrete hybrid fibers compressive and tensile strength

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纳米纤维素增强水泥基复合材料抗压强度机器学习预测

纳米纤维素增强水泥基复合材料抗压强度机器学习预测

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作者： aftab anwar（阿福）云南农业大学

学位级别：硕士

纤维素纳米纤维（CNFs）是建筑行业新引入的植生物基材料,符合低碳发展理念。人工智能（AI）技术的使用,特别是机器学习（ML）模型,有助于建筑行业节能减排。获得CNFs抗压强度的方法是通过物理实验,获得结果既昂贵又耗时,因此工作效率... 详细信息

纤维素纳米纤维（CNFs）是建筑行业新引入的植生物基材料,符合低碳发展理念。人工智能（AI）技术的使用,特别是机器学习（ML）模型,有助于建筑行业节能减排。获得CNFs抗压强度的方法是通过物理实验,获得结果既昂贵又耗时,因此工作效率会很低。这就是为什么技术进步允许通过其他方法以较低的成本解决工程问题,例如经验回归、数值模拟和使用机器学习方法。这些方法允许预测CNFs的抗压强度与不同组分（水泥,水,CNFs,减水剂,细骨料,粗骨料和年龄）的设计混合物的比例。本研究旨在利用监督回归机器学习技术进行分析,确定纤维素纳米纤维增强水泥基复合材料、混凝土、水泥浆和水泥砂浆的抗压强度。为了完成这项任务,准备了一个包含695个数据点的基于实验的水泥复合材料数据集,并将其分为两类（训练数据集=70%,测试数据集=30%）,用于ML模型的演变。该水泥基复合材料数据集分别分为混凝土、水泥浆和水泥砂浆数据集的196、266和233个观测值。分别分析了水泥基复合材料、混凝土、水泥浆和水泥砂浆4个数据集。有7个自变量:水泥（kg/m）、水（kg/m）、CNFs（kg/m）、减水剂（kg/m）、细骨料（kg/m）、粗骨料（kg/m）和龄期（天）变量作为输入,1个因变量:CNFs钢筋混凝土的抗压强度fc（MPa）作为水泥基复合材料数据集的输出。同样,混凝土数据集有7个自变量,水泥浆数据集有5个自变量,水泥砂浆数据集有6个自变量作为输入变量,1个因变量作为输出变量。首先,在Jupyter Notebook软件中通过相关系数分析、描述性分析、异常值分析、多元分析和密度曲线等方法进行数据集分析,研究水泥基复合材料、混凝土、水泥浆和水泥砂浆设计数据集的性能和强度。设计数据集分析结果表明:变量之间的相关性较低,异常值数量非常少,偏度极小,这确保了数据集对模型开发的满意度和可接受性。其次,开发并实现了机器学习模型的参数:随机森林（RF）、线性回归（LR）、支持向量回归器（SVR）、梯度提升回归器（GBR）、Ada提升回归器（ABR）、K-邻居回归器（KNN）、袋装回归器（BR）、XG提升回归器（XGBR）、决策树（DT）和修剪决策树（PDT）。针对水泥基复合材料、混凝土、水泥浆和水泥砂浆数据集分析了每个模型,以比较所开发模型的性能。使用以下指标来衡量模型的能力和性能:R、MAPE、MAE、MSE和RMSE。指标结果指出,70%的模型（RF、BR、XGBR、DT、GBR、ABR和KNN）预测CNFs水泥基复合材料的抗压强度具有坚实的能力（R>0.72、MAPE≤0.1和MAE≤5）,确认R值大于0.60且指标值非常小。同样,混凝土的8种型号（RF、BR、XGBR、DT、GBR、ABR、KNN、SVR）、7种水泥浆模型（RF、BR、XGBR、DT、GBR、ABR和KNN）,水泥砂浆的6种型号（RF、BR、XGBR、GBR、ABR和KNN）具有较强的抗压强度预测能力。水泥基复合材料数据集结果表明RF、BR和DT模型表现出最高的性能精度。混凝土数据集的结果表明XGBR、GBR和RF模型表现出最高的性能精度。水泥浆数据集结果表明XGBR、DT和GBR模型的性能精度最高。水泥砂浆数据集结果表明KNN、BR和RF模型的性能精度最高。根据RF、DT、XGBR、GBR和ABR模型的敏感性分析,水和水泥是CNFs增强水泥基复合材料预测影响最大的因素,而粗骨料的影响变量最小。在具体数据集中,粗骨料和CNFs自变量对输出变量的参与度显著。此外,水泥浆数据集中的水泥和水、水泥砂浆数据集中的水和龄期比其他自变量做出了显着的贡献。最后,可以得出结论,RF、BR和DT模型适用于水泥基复合材料,XGBR、GBR和RF模型适用于混凝土,XGBR、DT和GBR模型适用于水泥浆,以及KNN、BR和RF模型适用于水泥砂浆。因此,RF是这项研究的最佳预测模型。

关键词：机器学习 CNFs 水泥基复合材料抗压强度预测

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Exogenous application of bio-stimulants and growth retardants improve nutrient absorption and fiber quality in upland cotton

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Journal of Cotton Research 2024年第2期7卷 137-147页

作者： Al-Khayri Jameel M. Arif Muhammad Kareem Shadia Hama Salih anwar Adeel Dehghanisanij Hossein Emami Somayeh Yasmeen Azra aftab Komal Negm Mohamed Department of Agricultural Biotechnology College of Agriculture and Food SciencesKing Faisal University31982 Al‑AhsaSaudi Arabia Water Resources Zone Irrigation Department PunjabD.G.KhanPakistan Department of Biotechnology and Crop Science College of Agricultural Engineering SciencesUniversity of SulaimaniSulaimaniIraq Department of Agronomy PMAS-Arid Agriculture UniversityRawalpindiPakistan Agricultural Research Education and Extension OrganizationAgricultural Engineering Research InstituteKarajAlborzIran Department of Water Engineering University of TabrizTabrizIran Department of Agronomy Bahauddin Zakariya UniversityMultanPakistan Department of Plant Breeding and Genetics Bahauddin Zakariya UniversityMultanPakistan Agricultural Research Center Cotton Research InstituteGiza 12619Egypt

Background Natural and synthetic plant growth regulators are essential for plant health,likewise these regulators also play a role in increasing organic production productivity and improving quality and yield *** the present study,we have evaluated the effects of foliar applied plant growth regulators,i.e.,moringa leaf extract(MLE)and mepiquat chloride(MC)alone and in combination MC and MLE on the conventional cotton cultivar(CIM 573)and transgenic one(CIM 598).The growth regulators were applied at the start of bloom,45 and 90 days after *** The application of MC and MLE at 90 days after blooming significantly improved the relative growth rate,net assimilation rate,the number of bolls per plant,and seed cotton ***,the combined application of MLE and MC at 90 days after blooming significantly boosted the nitrogen uptake in locules,as well as the phosphorus and potassium uptake in the leaves of both cotton *** application of MLE alone has considerably improved the nitrogen uptake in leaves,and phosphorus and potassium contents in locules of Bt and conventional cotton ***,Bt cotton treated with MLE at 90 days after blooming produced significantly higher ginning out turn and oil *** in combination(MLE+MC)at 90 days after blooming produced considerably higher micronaire value,fiber strength,and staple length in conventional *** The natural growth enhancer,MLE is a rich source of minerals and zeatin,improving the nutrient absorption and quality of cotton fiber in both conventional and Bt cotton cultivars.

关键词： Bio-stimulant Cotton Fiber quality Mepiquat chloride Moringa leaf extract Potassium accumulation Oil contents

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Visible light-driven photo remediation of hazardous cationic dye via Ce-doped WO_(3) nanostructures

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Journal of Rare Earths 2024年第5期42卷 869-878,I0003页

作者： Azra Haroon Kaseed anwar Arham S.Ahmed Department of Physics Aligarh Muslim University202002AligarhIndia Interdisciplinary Nanotechnology Centre Aligarh Muslim University202002AligarhIndia

Ce-doped WO_(3) nanoparticles were successfully synthesized by the sol-gel method and characterized through advanced characterization *** high resolution transmission electron microscopy(HRTEM)and scanning electron microscopy(SEM)results show a reduction in the agglomeration of nanoparticles upon *** energy dispersive X-ray(EDX)analysis validates the existence of the Ce element in all the doped samples.X-ray photoelectron spectroscopy(XPS)and Raman spectra justify the presence of structural defects(oxygen vacancies)and successful formation of the monoclinic WO_(3) phase,*** Kubelka-Munk function indicates a decrease in band gap with doping,while photoluminescence(PL)spectra show intense visible and UV emissions,Significantly,all doped samples exhibit higher photocatalytic performance than pure WO_(3) nanoparticles,with the 6 wt%Ce-doped sample displaying the highest degradation *** with Ce can help to increase the surface area of WO_(3),thereby improving its photoactivity,Moreover,a correlation between PL and photocatalysis is established in the light of oxygen vacancies suggesting a direct dependence of high photocatalytic activity on strong PL signals of WO_(3) *** experiments further reveal that the degradation process is primarily driven by active species,providing insight into a plausible photocatalytic mechanism.

关键词： WO_(3) Rare-earth element Environmental crisis Oxygen vacancies Luminescence Photocatalysis

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Perception beyond sight:Investigating the cognitive maps of congenitally blind individuals in urban environments

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Frontiers of Architectural Research 2024年第4期13卷 809-821页

作者： anwar Ibrahim Hikmat HAli Zainab Mahmoud College of Architecture and Design Jordan University of Science and TechnologyIrbidJordan College of Engineering and Architecture Al Yamamah UniversityRiyadhKSA

This study explores the challenges faced by congenitally blind individuals in navigating urban ***,this research investigates the factors that contribute to the construction of city mental mapping for individuals who are born ***-one congenitally blind individuals from the University of Jordan were asked to define and describe specific elements of the city based on their personal experiences and ***,participants were guided through two urban paths:familiar and *** participants were asked to complete a survey regarding their experiences during the *** collected data was analyzed by using thematic *** results revealed that congenitally blind individuals construct their mental image of the city by using their three senses of touching,hearing,and smelling,as well as their safety and *** mental image consists of five key elements:links,reference points,areas,separators,and *** the small size of the study sample and the specificity of the context,the results of this study will tremendously help planners in designing highly inclusive urban *** characteristics that can be recognized by the blinds will enhance their accessibility of urban spaces,encourage independent mobility,increase the quality of life and social inclusion for them.

关键词： Mental map City image Congenital blind Cognitive mapping Environmental perception

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Ultrahydrophobic melamine sponge via interfacial modification with reduced graphene oxide/titanium dioxide nanocomposite and polydimethylsiloxane for oily wastewater treatment

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Water Science and Engineering 2024年第2期17卷 139-149页

作者： Hamidatu Alhassan Ying Woan Soon anwar Usman Voo Nyuk Yoong Department of Physics Universiti Brunei DarussalamBandar Seri Begawan BE1410Brunei Department of Chemical Sciences Universiti Brunei DarussalamBandar Seri Begawan BE1410Brunei

Three-dimensional(3D)porous absorbents have attracted significant attention in the oily wastewater treatment technology due to their high porosity and *** their amphiphilic surface,they have a propensity to simultaneously absorb water and oil,which restricts their range of *** this study,a reduced graphene oxide and titanium dioxide nanocomposite(rGO/TiO_(2))was used to fabricate an ultra-hydrophobic melamine sponge(MS)through interfacial modification using a solution immersion *** further modify it,poly-dimethylsiloxane(PDMS)was grafted onto its surface to establish stronger covalent bonds with the *** water contact angle of the sponge(rGO/TiO_(2)/PDMS/MS)was 164.2°,which satisfies the condition for *** evidence of its water repellency was demonstrated by the Cassie-Baxter theory and the lotus leaf *** a result of the increased density of rGO/TiO_(2)/PDMS/MS,it recorded an initial capacity that was 2 g/g lower than the raw MS for crude oil *** raw MS retained 53% of its initial absorption capacity after 20 cycles of absorption,while rGO/TiO_(2)/PDMS/MS retained 97%,suggesting good *** oil and organic solvent recovery(90%-96%)was demonstrated by rGO/TiO_(2)/PDMS/MS in oil-water *** a continuous separation system,it achieved a remarkable separation efficiency of 2.4×10^(6)L/(m^(3)·h),and in turbulent emulsion separation,it achieved a demulsification efficiency of 90%-91%.This study provides a practical substitute for massive oil spill cleaning.

关键词： Oily wastewater Reduced graphene oxide Polydimethylsiloxane(PDMS) Emulsion separation Melamine sponge

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Responses of Inter Annual Variability of Vegetation NPP to Climate Variables using Satellite Techniques in Eastern Sudan

Responses of Inter Annual Variability of Vegetation NPP to C...

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作者： anwar MOHAMEDELHASSAN TAJALMOLA MOHAMED 西北师范大学

学位级别：硕士

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Expansion of human umbilical cord derived mesenchymal stem cells in regenerative medicine

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World Journal of Stem Cells 2024年第4期16卷 410-433页

作者： Shafiqa Naeem Rajput Bushra Kiran Naeem anwar Ali Asmat Salim Irfan Khan Dr.Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological SciencesUniversity of KarachiKarachi 75270SindhPakistan Surgical Unit 4 Dr.Ruth KM Pfau Civil HospitalKarachi 74400Pakistan Department of Physiology University of KarachiKarachi 75270Pakistan Center for Regenerative Medicine and Stem Cells Research and Department of Ophthalmology and Visual SciencesThe Aga Khan UniversityKarachi 74800SindhPakistan

BACKGROUND Stem cells are undifferentiated cells that possess the potential for self-renewal with the capacity to differentiate into multiple *** humans,their limited numbers pose a challenge in fulfilling the necessary demands for the regeneration and repair of damaged tissues or *** suggested that mesenchymal stem cells(MSCs),necessary for repair and regeneration via transplantation,require doses ranging from 10 to 400 million ***,the limited expansion of MSCs restricts their therapeutic *** To optimize a novel protocol to achieve qualitative and quantitative expansion of MSCs to reach the targeted number of cells for cellular transplantation and minimize the limitations in stem cell therapy *** Human umbilical cord(hUC)tissue derived MSCs were obtained and *** cultured cells were subjected to the following evaluation pro-cedures:Immunophenotyping,immunocytochemical staining,trilineage differentiation,population doubling time and number,gene expression markers for proliferation,cell cycle progression,senescence-associatedβ-galactosidase assay,human telomerase reverse transcriptase(hTERT)expression,mycoplasma,cytomegalovirus and endotoxin *** Analysis of pluripotent gene markers Oct4,Sox2,and Nanog in recultured hUC-MSC revealed no significant *** immunophenotypic markers CD90,CD73,CD105,CD44,vimentin,CD29,Stro-1,and Lin28 were positively expressed by these recultured expanded MSCs,and were found negative for CD34,CD11b,CD19,CD45,and *** recultured hUC-MSC population continued to expand through passage *** gene expression of Pax6,BMP2,and TGFb1 showed no significant variation between recultured hUC-MSC ***,a significant increase(P<0.001)in the mitotic phase of the cell cycle was observed in recultured *** senescence markers(hTERT expression andβ-galactosidase activity)did not show any negative effect on recultured hUC-

关键词： Human umbilical cord Mesenchymal stem cells Expansion Cell proliferation In vitro expansion Senescence

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Survey of Indoor Localization Based on Deep Learning

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Computers, Materials & Continua 2024年第5期79卷 3261-3298页

作者： Khaldon Azzam Kordi Mardeni Roslee Mohamad Yusoff Alias Abdulraqeb Alhammadi Athar Waseem anwar Faizd Osman Centre for Wireless Technology Faculty of EngineeringMultimedia UniversityCyberjaya63100Malaysia Communication Systems&Networks Research Lab Malaysia-Japan International Institute of TechnologyUniversiti Teknologi MalaysiaKuala Lumpur54100Malaysia Department of Electrical Engineering(DEE) International Islamic UniversityIslamabad44000Pakistan Rohde&Schwarz(M)Sdn Bhd Shah Alam40150Malaysia

This study comprehensively examines the current state of deep learning (DL) usage in indoor *** emphasizes the significance and efficiency of convolutional neural networks (CNNs) and recurrent neuralnetworks (RNNs). Unlike prior studies focused on single sensor modalities like Wi-Fi or Bluetooth, this researchexplores the integration of multiple sensor modalities (e.g.,Wi-Fi, Bluetooth, Ultra-Wideband, ZigBee) to expandindoor localization methods, particularly in obstructed environments. It addresses the challenge of precise objectlocalization, introducing a novel hybrid DL approach using received signal information (RSI), Received SignalStrength (RSS), and Channel State Information (CSI) data to enhance accuracy and stability. Moreover, thestudy introduces a device-free indoor localization algorithm, offering a significant advancement with potentialobject or individual tracking applications. It recognizes the increasing importance of indoor positioning forlocation-based services. It anticipates future developments while acknowledging challenges such as multipathinterference, noise, data standardization, and scarcity of labeled data. This research contributes significantly toindoor localization technology, offering adaptability, device independence, and multifaceted DL-based solutionsfor real-world challenges and future advancements. Thus, the proposed work addresses challenges in objectlocalization precision and introduces a novel hybrid deep learning approach, contributing to advancing *** deep learning-based indoor localization techniques have improved accuracy, challenges likedata noise, standardization, and availability of training data persist. However, ongoing developments are expectedto enhance indoor positioning systems to meet real-world demands.

关键词： Deep learning indoor localization wireless-based localization

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Crystallization of battery-grade lithium carbonate with high recovery rate via solid-liquid reaction

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Particuology 2024年第9期92卷 95-105页

作者： Chaofan Wu Longjin Jiang Wei Wang Bin Dong Zhidong Chang Daixiang Wei Hira anwar Minghui Zhang Dekun Gao School of Chemistry and Biological Engineering University of Science and Technology BeijingBeijing100083China Anhui Chaoyue Environmental Protection Technology Co. LtdChuzhou239060China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100190China Anhui Huihong Technology Co. LtdChuzhou239060China

Lithium carbonate(Li_(2)CO_(3))stands as a pivotal raw material within the lithium-ion battery ***,we propose a solid-liquid reaction crystallization method,employing powdered sodium carbonate instead of its solution,which minimizes the water introduction and markedly elevates one-step lithium recovery *** kinetic calculations,the Li_(2)CO_(3)solid-liquid reaction crystallization process conforms by the Avrami equation rather than shrinking core model,which means the dissolution rate of Na_(2)CO_(3)is the most important factor affecting the reaction *** effects of reaction conditions such as temperature and stirring speed on the Li_(2)CO_(3)precipitation behavior were *** results indicated that temperature is a most essential parameter than other reaction conditions or stirring *** exceptional 93%recovery of Li_(2)CO_(3)at 90℃with a remarkable purity of 99.5%was achieved by using 1.2 M ratio of Na_(2)CO_(3)/Li_(2)SO_(4).This method provides a new idea for the efficient preparation of battery-grade Li_(2)CO_(3).

关键词： Lithium recovery Lithium sulfate Reaction crystallization Battery-grade lithium carbonate

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