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Heavy metal contamination and health risk assessment of road dust from landfills in dhaka-Narayanganj, bangladesh

Emerging Contaminants 2024年第1期10卷 117-125页

作者： Mrittika Chakraborty Md Masudur Rahman Rahat Tasrina Rabia Choudhury Refayat Nigar Guorui Liu Ahsan Habib department of chemistry University of DhakaDhaka1000Bangladesh Analytical chemistry Laboratory Chemistry DivisionAtomic Energy Centre Dhaka Bangladesh Atomic Energy CommissionDhaka1000Bangladesh State Key Laboratory of Environmental chemistry and Ecotoxicology Research Center for Eco-Environmental ScienecsChinese Academy of SciencesBeijing100085China

In the recent years,air pollution has become an alarming issue for human health in many rapidly growing megacities including dhaka and ***,pollution status and health risk have been assessed by the road dusts collected from landfills in dhaka and Narayanganj through determination of heavy metals including Pb,Cd,Cr,As,Cu,Ni,Zn and Mn using atomic absorption *** collected dust samples have been grouped into three sizes,for example,150,75 and<75μm,to assess the degree of heavy metal accumulation in the dust *** dust particles were accumulated with high concentrations of Pb and As at Matuail landfills,whereas Cd,Cr,Zn,and Mn concentrations were highest at Narayanganj *** finer particles,for example 75μm,accumulated substantial concentrations of heavy *** index and pollution load index(PLI)results revealed that all of the sites were deteriorated by Pb,Cd,Cu,Zn and *** results exhibited that the quality of the Matuail landfill area was severely *** terms of non-carcinogenic health risk,the values of hazard quotient for ingestion were greater than those for inhalation and dermal *** adult groups,hazard index values for the Matuail landfills and medical waste incineration sites were greater than 1,while for the children groups,the values for the same areas,including the Narayanganj landfills,were also larger than *** values were at least one order of magnitude higher for the children groups than for the adult *** the results,it would be reasonable to draw the conclusion that non-carcinogenic health risks for children may be more prevalent in the relevant areas.

关键词： Road dusts Heavy metals Landfills bangladesh Degree of accumulation Health risk assessment

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ZnO Incorporated Acrylamide Grafted Chitosan Based Composite Film for Advanced Wound Healing Applications

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Open Journal of applied Sciences 2024年第4期14卷 1034-1051页

作者： Khodeja Afrin Kaniz Fatema Fariha Afrose Md. Abdus Samad Azad Md. Shamim Akter Md. Saiful Alam Papia Haque Yeasmin Akter Newaz Mohammed Bahadur department of applied chemistry and Chemical Engineering Noakhali Science and Technology University Noakhali Bangladesh department of applied chemistry and Chemical Engineering University of Dhaka Dhaka Bangladesh

This study was carried out to prepare ZnO nanoparticles incorporated acrylamide grafted chitosan composite film for possible biomedical application especially drug loading in wound healing. ZnO nanoparticles were prepared by co-precipitation method from zinc acetate di-hydrate and incorporated in acrylamide grafted chitosan. FT-IR and TGA of the prepared composite film confirmed the successful incorporation of ZnO nanoparticles in the acrylamide-grafted polymer matrix. SEM images showed that the ZnO nanoparticles were homogeneously distributed on the porous matrix of the composite film. Water uptake and buffer uptake analysis revealed that the composite film could hold water and buffer sufficiently, which facilitated the absorption of exudate from the wound site. Amoxicillin was loaded in the prepared composite film and the maximum loading efficiency was found to be 67.33% with drug concentration of 300 ppm. In vitro studies showed greater antimicrobial activity of drug-loaded composite film compared to both pure film and standard antibiotic disc. Finally, the In vivo mouse model showed maximum healing efficiency compared to conventional gauge bandages because the loading of antibiotic in the film produced a synergistic effect and healing time was reduced.

关键词： Chitosan ZnO Nanoparticles Wound Management Acrylamide Grafting Bacterial Resistance Drug Loading

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Gas Chromatographic Method for Identification and Quantification of Commonly Used Residual Solvents in Pharmaceuticals Products

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American Journal of Analytical chemistry 2024年第8期15卷 241-252页

作者： Sreekanta Nath Dalal Pranab Kumar Das department of applied chemistry & Chemical Engineering Faculty of Engineering & Technology University of Dhaka Dhaka Bangladesh department of applied chemistry & Chemical Engineering Faculty of Engineering University of Rajshahi Rajshahi Bangladesh

Background: Impurities are not expected in the final pharmaceutical products. All impurities should be regulated in both drug substances and drug products in accordance with pharmacopeias and ICH guidelines. Three different types of impurities are generally available in the pharmaceutical’s product specification: organic impurities, inorganic impurities, and residual solvents. Residual solvents are organic volatile chemicals used or generated during the manufacturing of drug substances or drug products. Purpose: The aim of this study is to develop a cost-effective gas chromatographic method for the identification and quantification of some commonly used solvents—methanol, acetone, isopropyl alcohol (IPA), methylene chloride, ethyl acetate, tetrahydrofuran (THF), benzene, toluene, and pyridine—in pharmaceutical product manufacturing. This method will be able to identify and quantify the multiple solvents within a single gas chromatographic procedure. Method: A gas chromatography (GC) equipped with a headspace sampler and a flame ionization detector, and a column DB 624, 30-meter-long × 0.32-millimeter internal diameter, 1,8 μm-thick, Brand-Agilent was used to develop this method. The initial GC oven temperature was 40°C and held for 5 minutes. It was then increase to 80˚C at a rate of 2˚C per minute, followed by a further increase to 225˚C at a rate of 30˚C per minute, with a final hold at 225˚C for 10 minutes. Nitrogen was used as a carrier gas at a flow rate of 1.20 mL per minute. Dimethyl sulfoxide (DMSO) was selected as sample solvent. Results: The developed method is precise and specific. The percent RSD for the areas of six replicate injections of this gas chromatographic method was within 10.0 and the recovery result found within 80.0% to 120.0%.

关键词： Method Development Gas Chromatography Compendial Method GDP Specificity Recovery

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Robustness Study and Superior Method Development and Validation for Analytical Assay Method of Atropine Sulfate in Pharmaceutical Ophthalmic Solution

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American Journal of Analytical chemistry 2024年第5期15卷 151-164页

作者： Md. Nazmus Sakib Chowdhury Sreekanta Nath Dalal Md. Ariful Islam Md. Anwar Hossain Pranab Kumar Das Shakawat Hossain Parajit Das department of Pharmacy Bangabandhu Sheikh Mujibur Rahman Science and Technology University Gopalganj Bangladesh department of applied chemistry and Chemical Engineering University of Dhaka Dhaka Bangladesh department of applied chemistry and Chemical Engineering University of Chittagong Chattogram Bangladesh department of applied chemistry and Chemical Engineering Islamic University Kushtia Bangladesh department of applied chemistry and Chemical Engineering University of Rajshahi Rajshahi Bangladesh department of Pharmacy International Islamic University Chittagong Chittagong Bangladesh department of applied chemistry and Chemical Engineering Bangabandhu Sheikh Mujibur Rahman Science and Technology University Gopalganj Bangladesh

Background: The robustness is a measurement of an analytical chemical method and its ability to contain unaffected by little with deliberate variation of analytical chemical method parameters. The analytical chemical method variation parameters are based on pH variability of buffer solution of mobile phase, organic ratio composition changes, stationary phase (column) manufacture, brand name and lot number variation;flow rate variation and temperature variation of chromatographic system. The analytical chemical method for assay of Atropine Sulfate conducted for robustness evaluation. The typical variation considered for mobile phase organic ratio change, change of pH, change of temperature, change of flow rate, change of column etc. Purpose: The aim of this study is to develop a cost effective, short run time and robust analytical chemical method for the assay quantification of Atropine in Pharmaceutical Ophthalmic Solution. This will help to make analytical decisions quickly for research and development scientists as well as will help with quality control product release for patient consumption. This analytical method will help to meet the market demand through quick quality control test of Atropine Ophthalmic Solution and it is very easy for maintaining (GDP) good documentation practices within the shortest period of time. Method: HPLC method has been selected for developing superior method to Compendial method. Both the compendial HPLC method and developed HPLC method was run into the same HPLC system to prove the superiority of developed method. Sensitivity, precision, reproducibility, accuracy parameters were considered for superiority of method. Mobile phase ratio change, pH of buffer solution, change of stationary phase temperature, change of flow rate and change of column were taken into consideration for robustness study of the developed method. Results: The limit of quantitation (LOQ) of developed method was much low than the compendial method. The % RSD fo

关键词： Robustness Method Validation HPLC Compendial Method Method Development GDP LOQ

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Development of Modified Glasses by Transparent, Functional Hybrid Sol-Gel Nano-Ceramic Coatings, a Comparative Study

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World Journal of Engineering and technology 2024年第1期12卷 170-184页

作者： Md. Barkat Ullah Yeasmin Akter Khodeja Afrin Md. Saiful Quddus department of applied chemistry and Chemical Engineering Noakhali Science and Technology University Noakhali Bangladesh bangladesh Council of Scientific and Industrial Research (BCSIR) Dhaka Bangladesh

This paper concentrates on the development of glasses with self-cleaning surfaces exhibiting high water contact angles. In this study, we prepared super-hydrophobic nano-ceramic coated glass based on titania & silica using simple sol-gel & dip coating methods and studied the best composition of the coatings by altering ratios of titanium tetraisopropoxide (TTIP)/tetraethyl orthosilicate (TEOS) with different homogenizing agents. We characterized the coatings by surface roughness measurement, percentage of optical transmission, static contact angle, near-infrared (NIR) transmission, and diffuse reflectance. The fabrication of coatings on glass substrates played an important role in increasing the water contact angle of about 95° and visible & NIR transmission of about 90%. We compared our modified glass substrate with commercial low emissivity (Low E) glass using X-ray diffraction (XRD) analysis, which showed pure amorphous surface claiming excellent wettability and thus the prepared glass substrate could have a variety of applications in different fields.

关键词： Sol-Gel Nano-Ceramic Coatings Self-Cleaning Glass Water Contact Angle Optical Transmission

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Highly elastic 2D covalent organic framework films of interwoven single crystals

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National Science Review 2024年第7期11卷 71-72页

作者： Tongwen Xu Key Laboratory of Precision and Intelligent chemistry Department of Applied ChemistrySchool of Chemistry and Materials ScienceUniversity of Science and Technology of China

Two-dimensional(2D) materials feature angstrom-scale pores and tunable pore chemistry, demonstrating great potential for applications including flexible electronics and *** ion/molecule transport in the sub-nanometer-sized pore confinement often reveals phenomena not seen in bulk materials [1]. Yet, the practical application of 2D materials is hindered by their poor mechanical properties.

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Supporting IrO_(x) nanosheets on hollow TiO_(2) for highly efficient acidic water splitting

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Nano Research 2024年第8期17卷 6903-6909页

作者： Ge Yu Ruilong Li Yanmin Hu Xingen Lin Ze Lin Dongyang Wu Gongming Wang Xun Hong Center of Advanced Nanocatalysis(CAN) Department of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China

The efficiency of proton exchange membrane water electrolysis(PEM-WE)for hydrogen production is heavily dependent on the noble metal iridium-based ***,the scarcity of iridium limits the large-scale application of *** address this issue,it is promising to select an appropriate support because it not only enhances the utilization efficiency of noble metals but also improves mass transport under high ***,we supported amorphous IrO_(x) nanosheets onto the hollow TiO_(2) sphere(denoted as IrO_(x)),which demonstrated excellent performance in acidic electrolytic water ***,the annealed IrO_(x)catalyst at 150℃in air exhibited a mass activity of 1347.5 A·gIr^(−1),which is much higher than that of commercial IrO_(2) of 12.33 A·gIr^(−1) at the overpotential of 300 mV for oxygen evolution reaction(OER).Meanwhile,the annealed IrO_(x) exhibited good stability for 600 h operating at 10 mA·cm^(−2).Moreover,when using IrO_(x) and annealed IrO_(x) catalysts for water splitting,a cell voltage as low as 1.485 V can be achieved at 10 mA·cm^(−2).The cell can continuously operate for 200 h with negligible degradation of performance.

关键词： oxygen evolution reaction hydrogen evolution reaction amorphous IrO_(x) hollow TiO_(2) proton exchange membrane water electrolysis

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Characteristics of Multi-Objective Linear Programming Problem and Multi-Objective Linear Fractional Programming Problem Taking Maximum Value of Multi-Objective Functions

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applied Mathematics 2024年第1期15卷 22-32页

作者： Samsun Nahar Md. Asadujjaman Khadiza Begum Mahede-Ul-Hassan Md. Abdul Alim department of Basic Sciences and Humanities University of Asia Pacific Dhaka Bangladesh department of Mathematics University of Dhaka Dhaka Bangladesh Computer Science and Engineering department Prime University Dhaka Bangladesh department of Mathematics and Statistics Bangladesh University of Business and Technology Dhaka Bangladesh department of Mathematics Bangladesh University of Engineering and Technology Dhaka Bangladesh

In this paper, a new statistical averaging technique is proposed for finding an optimal solution to a multi-objective linear fractional programming problem (MOLFPP) and multi-objective linear programming problem (MOLPP) by using new arithmetic averaging method and new geometric averaging method. It is significantly noticeable same characteristics among all the technique while taking maximum or minimum among all optimized values for multi-objective functions using simplex algorithm. The characteristics provided from the problems are verified by the numerical examples.

关键词： MOLPP MOLFPP New Arithmetic Averaging Method New Geometric Averaging Method

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AutoML: A systematic review on automated machine learning with neural architecture search

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Journal of Information and Intelligence 2024年第1期2卷 52-81页

作者： Imrus Salehin Md.Shamiul Islam Pritom Saha S.M.Noman Azra Tuni Md.Mehedi Hasan Md.Abu Baten department of Computer Engineering Dongseo University47 Jurye-roSasang-guBusan 47011Republic of Korea department of Computer Science and Engineering Daffodil International UniversityDhaka 1216Bangladesh department of Computer Science and Engineering Bangladesh University of Business and TechnologyDhaka 1216Bangladesh Faculty of Computer Science and Engineering Frankfurt University of Applied SciencesFrankfurt 60318Germany department of Computer Science and Engineering University of Asia PacificDhaka 1205Bangladesh department of Computer Science and Engineering Ahsanullah University of Science and TechnologyDhaka 1208Bangladesh department of Computer Science and Engineering Northern University BangladeshDhaka 1215Bangladesh

AutoML(Automated Machine Learning)is an emerging field that aims to automate the process of building machine learning *** emerged to increase productivity and efficiency by automating as much as possible the inefficient work that occurs while repeating this process whenever machine learning is *** particular,research has been conducted for a long time on technologies that can effectively develop high-quality models by minimizing the intervention of model developers in the process from data preprocessing to algorithm selection and *** this semantic review research,we summarize the data processing requirements for AutoML approaches and provide a detailed *** place greater emphasis on neural architecture search(NAS)as it currently represents a highly popular sub-topic within the field of *** methods use machine learning algorithms to search through a large space of possible architectures and find the one that performs best on a given *** provide a summary of the performance achieved by representative NAS algorithms on the CIFAR-10,CIFAR-100,ImageNet and wellknown benchmark ***,we delve into several noteworthy research directions in NAS methods including one/two-stage NAS,one-shot NAS and joint hyperparameter with architecture *** discussed how the search space size and complexity in NAS can vary depending on the specific problem being *** conclude,we examine several open problems(SOTA problems)within current AutoML methods that assure further investigation in future research.

关键词： AutoML Neural architecture search Advance machine learning Search space Hyperparameter optimization

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A low-swelling hydrogel as a multirole sealant for efficient dural defect sealing and prevention of postoperative adhesion

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National Science Review 2024年第6期11卷 294-307页

作者： Xueliang Cheng Zhen Zhang Hui Ren Zheng Zou Yu Zhang Yang Qu Xuesi Chen Jianwu Zhao Chaoliang He CAS Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of Sciences department of Orthopedics The Second Norman Bethune Hospital of Jilin University School of applied chemistry and Engineering University of Science and Technology of China

Dural defects and subsequent complications, including cerebrospinal fluid（CSF） leakage, are common in both spine surgery and neurosurgery, and existing clinical treatments are still unsatisfactory. In this study, a tissue-adhesive and low-swelling hydrogel sealant comprising gelatin and o-phthalaldehyde（OPA）-terminated 4-armed poly（ethylene glycol）(4aPEG-OPA) is developed via the OPA/amine condensation reaction. The hydrogel shows an adhesive strength of 79.9 ± 12.0 k Pa on porcine casing and a burst pressure of 208.0 ± 38.0 cm H2O. The hydrogel exhibits a low swelling ratio at physiological conditions, avoiding nerve compression in the limited spinal and intracranial spaces. In rat and rabbit models of lumbar and cerebral dural defects, the 4aPEG-OPA/gelatin hydrogel achieves excellent performance in dural defect sealing and preventing CSF leakage. Moreover, local inflammation, epidural fibrosis and postoperative adhesion in the defect areas are markedly reduced. Thus, these findings establish the strong potential of the hydrogel sealant for the effective watertight closure of dural defects.

关键词： hydrogel sealant watertight closure low swelling o-phthalaldehyde chemistry dural sealing

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