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Proton conductivity performance and its correlation with physiochemical properties of proton exchange membrane(PEM)

Chinese Journal of Chemical Engineering 2024年第10期74卷 100-116页

作者： Mirza Nusrat Sweety Md Abdus Salam Hydrogen Energy Laboratory Bangladesh Council of Scientific and Industrial Research(BCSIR)Chattogram 4220Bangladesh Institute of Mining Mineralogy and Metallurgy(IMMM)BCSIRJoypurhat 5900Bangladesh bcsir dhaka laboratories Dhaka 1205Bangladesh

Graphene oxide(GO)filler containing diversified Nafion-based proton exchange membrane(PEM)is studied to know the unique physical and chemical properties and performances of ***-SPEEK 1%-GO 0.75%(NSG-0.75%)composite shows the highest proton conductivity of 0.327 S·cm^(-1) at 90℃ and 100%RH(relative humidity)among all the PEM *** descending order of significant proton conductivity is found as;Nafion-sPGO(1%)0.306 S·cm^(-1)>Nafion/ZIF-8@GO 0.280 S·cm^(-1)>Nafion/PGO(2%)0.277 S·cm^(-1)>Nafion/GO-sulfur(3%)0.232 S·cm^(-1)>Nafion/GO-poly-SPM-co-PEGMEMA(1%)0.229 S·cm^(-1)>Nafion/Ce-sPGO(1%)0.215 S·cm^(-1).The proton conductivity,water uptake capacity and ion exchange capacity,hydration number,thermal and oxidative stability,mechanical integrity(tensile strength),maximum power,and current density are found to be increased while activation energy and fuel crossover show a decrement as GO or modified GO is incorporated in the Nafion *** component analysis(PCA)predicted a significant correlation between the proton conductivity and the properties;the water uptake capacity,ion exchange capacity,hydration number,maximum power density,and maximum current density are 0.598%,0.688%,0.894%,0.980%,and 0.852%accordingly.A multiple linear model equation of proton conductivity is defined with the parameters of water uptake capacity,ion exchange capacity,hydration number,maximum power density,and maximum current density whereas the regression coefficient is 0.9923.

关键词： Fuel cells Membranes Nafion GO-filler Proton conductivity Principal component analysis

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Extraction and characterization of alumina nanopowders from aluminum dross by acid dissolution process

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International Journal of Minerals,Metallurgy and Materials 2015年第4期22卷 429-436页

作者： Saifur Rahman Sarker Zahangir Alam Rakibul Qadir M A Gafur Mohammad Moniruzzaman Department of Applied Chemistry and Chemical Engineering University of dhaka Pilot Plant & Project Development Centre (PP& PDC) Bangladesh Council of Scientific and Industrial Research (BCSIR) bcsir laboratories Dhaka

A significant amount of aluminum dross is available as a waste in foundry industries in Bangladesh. In this study, alumina was ex- tracted from aluminum dross collected from two foundry industries situated in Dhamrai and Manikgang, near the capital city, dhaka. Alu- minum dross samples were found to approximately contain 75wt% A1203 and 12wt% SIO2. An acid dissolution process was used to recover the alumina value from the dross. The effects of various parameters, e.g., temperature, acid concentration, and leaching time, on the extrac- tion of alumina were studied to optimize the dissolution process. First, AI（OH）3 was produced in the form of a gel. Calcination of the AI（OH）3 gel at 1000℃, 1200℃, and 1400℃ for 2 h produced O-AlcOa, （t~＋O）-A1203, and u-alumina powder, respectively. Thermal charac- terization of the AI（OH）3 gel was performed by thermogravimetric/differential thermal analysis （TG/DTA） and differential scanning calo- rimetry （DSC）. The phases and crystallite size of the alumina were determined by X-ray diffraction analysis. The dimensions of the alumina were found to be on the nano level. The chemical compositions of the aluminum dross and alumina were determined by X-ray fluorescence （XRF） spectroscopy. The microstructure and morphology of the alumina were studied with scanning electron microscopy. The purity of the alumina extracted in this study was found to be 99.0%. Thus, it is expected that the obtained alumina powders can be potentially utilized as biomaterials.

关键词： aluminum dross alumina nanoparticles acid dissolution calcination X-ray fluorescence analysis

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Development of chemometric model for characterization of non-wood by FT-NIR data

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Journal of Bioresources and Bioproducts 2020年第3期5卷 196-203页

作者： Mohammad Nashir Uddin Taslima Ferdous Zahidul Islam M.Sarwar Jahan M.A.Quaiyyum bcsir laboratories DhakaBangladesh Council of Scientific and Industrial Research(BCSIR)Dhaka 1205Bangladesh Department of Applied Chemistry and Chemical Engineering University of DhakaDhaka 1000Bangladesh

In this study,a model for prediction of lignocellulose components of agricultural residues has been developed with Fourier Transformed Near Infrared(FT-NIR)spectroscopy *** calibration techniques(Principal Component Regression(PCR)and Partial Least Square Regression(PLSR))were assessed for prediction of lignin,holocellulose,α-cellulose,pentosan and ash,and found the PLSR better for lignin,holocellulose andα-*** PCR also produced better results for quantification of pentosan and *** range(7000-5000 cm^(-1))showed more informative than other parts of the spectral *** PLSR showed maximum value of R^(2)(R^(2)=0.91%)for prediction of *** the prediction of pentosan,the PCR was better(R^(2)=0.68%).The PCR also showed better results(R^(2)=86%)for quantification of *** determine amount of lignin,the PLSR was the best(R^(2)=0.83%)when the spectral data were de-trained and smoothed with Savitzky-Golay(S-G)filtering *** prediction ofα-cellulose,the PLSR was the best model(R^(2)=0.94%)when the data were pretreated with mean *** the best alternatives inNear Infrared(NIR)data preprocessing and calibration techniques,methods for quantification of lignocellulose components of agricultural residues have been developed which is rapid,cost effective,and less chemical intensive and easily usable in pulp and paper industries and pulp testing laboratories.

关键词： Agricultural residue Multivariate modeling Lignocellulose component

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Nutritional quality and safety aspects of wild vegetables consume in Bangladesh

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Asian Pacific Journal of Tropical Biomedicine 2016年第2期6卷 125-131页

作者： Miah Mohammed Abdus Satter Mohammed Murtaza Reza Linkon Khan Syeda Absha Jabin Nusrat Abedin Mohammed Faridul Islam Badhan Shaha Institute of Food Science and Technology Bangladesh Council of Scientific and Industrial Research (BCSIR) Department of Food Science and Technology Moulana Bhasani University bcsir laboratories dhaka Bangladesh Council of Scientific and Industrial Research (BCSIR)

Objective: To evaluate the nutritional composition, including major minerals, essential trace elements and toxic heavy metals of five different wild vegetables Dhekishak(Dryopteris filix-mas), Helencha(Enhydra fluctuans), Kalmishak(Ipomoea aquatica),Patshak(Corchorus capsularis) and Shapla stem(Nymphaea stellata) and their safety ***: Proximate parameters moisture, ash, fat, fiber, protein, carbohydrate and energy; major minerals Na, K, Ca and Mg; trace elements Fe, Zn and Cu; and toxic heavy metals Pb, Cd, Cr, Ni and Hg were evaluated in the selected wild vegetables using the standard food analysis ***: The results from nutritional analysis showed that all the wild vegetables used in this study had a low content of crude fat and high content of moisture, ash, crude protein,crude fiber, carbohydrate and energy having the recommended dietary allowances. The vegetables were also rich in major minerals Na, K, Ca and Mg, sufficient in essential trace elements Fe, Cu and Zn while the heavy metals Pb, Cr and Ni were detected higher in amount in all the vegetables except Patshak than the limits recommended by Food and Agriculture Organization/World Health Organization. The heavy metals Cd and Hg were not detected in any ***: The outcome of this study suggests that the wild vegetables have very good nutritional potential to meet the recommended dietary allowances, but special awareness should be taken for public health concern about the high level of Pb, Cr and Ni which exceed the Food and Agriculture Organization/World Health Organization recommended limits for the metals in vegetables.

关键词： Wild vegetables Nutritional quality Mineral contents Heavy metals Safety aspects

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Influence of Ni substitution on structural,morphological,dielectric,magnetic and optical properties of Cu-Zn ferrite by double sintering sol–gel technique

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Journal of Advanced Dielectrics 2019年第2期9卷 63-71页

作者： Mohammad Sajjad Hossain Yeasmin Akter Mohammad Shahjahan Muhammad Shahriar Bashar MostHosney Ara Begum MdMoazzem Hossain Suravi Islam Nazia Khatun MdAl-Mamun Industrial Physics Division BCSIR Laboratories Dhaka BCSIRDhaka-1205Bangladesh Department of Physics University of Chittagong Chottogram-4331Bangladesh Institute of Fuel Research and Development bcsir Dhaka-1205Bangladesh Bangladesh Atomic Energy Centre BAEC Dhaka-1000Bangladesh

Polycrystalline NiCuZn ferrite(Ni_(x)Cu_(0.3)Zn(0.7-x)Fe_(2)O_(4);x=0.2,0.3,0.4 and 0.5)were prepared through solgel auto combustion method applying double sintering ***,morphological,elemental analyses(EDS),Fourier-transform infrared spectroscopy(FTIR),Direct Current(DC)electrical resistivity,dielectric,magnetic and optical properties of prepared samples were *** profiles reveal the formation of simple cubic spinel structure without any traceable *** average crystallite size lies within the range of 22–29 *** parameter decreases with increasing Ni *** temperature DC resistivity was recorded from 6:39×10^(5)to 3:79×10^(5)Ω*** dielectric constant(ε)and loss factor(tanδ)were decreased with increase of frequency while AC conductivity *** absorption peak occurred at three different frequency ranges at 570-577 cm^(-1),1635-1662 cm^(-1)and 3439–3448 cm^(-1).Magnetic properties were investigated by using vibrating sample magnetometer(VSM).Decreasing trends were observed for saturation magnetization(Ms),magnetic coercivity(Hc)and remanant magnetization(Mr)with the increase of Ni *** band gap(-2.70-2.79 eV)were calculated from diffuse reflectance data by using Kubelka–Munk function.

关键词： Sol-gel NiCuZn ferrite FTIR DC resistivity dielectric optical properties

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Synthesis,structural investigation,dielectric and magnetic properties of Zn^(2+)-doped cobalt ferrite by the sol-gel technique

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Journal of Advanced Dielectrics 2018年第4期8卷 54-59页

作者： Mohammad Sajjad Hossain MdBadiul Alam Mohammad Shahjahan Most.Hosney Ara Begum MdMoazzem Hossain Suravi Islam Nazia Khatun Mukul Hossain Mohammad Saiful Alam Md.Al-Mamun Industrial Physics Division BCSIR Laboratories Dhaka BCSIRDhaka 1205Bangladesh Noakhali Science and Technology University Noakhali 3814 Bangladesh Daffodil International University dhaka 1205 Bangladesh Atomic Energy Centre dhaka dhaka 1000 Bangladesh

Zinc substituted cobalt ferrite nanoparticles with elemental composition Co_(1-x)Zn_(x)Fe_(2)O_(4)(x=0.0,0.2,0.4,0.6)were prepared by the sol-gel auto-combustion technique using Co,Fe,Zn nitrate as a precursor where nitrates to citrate was 1:*** as prepared powder of cobalt zinc ferrite was sintered at 900○C for 3 ***,morphological,dielectric and magnetic properties were studied by x-ray diffractometer(XRD),scanning electron microscope(SEM),high precision impedance analyzer and vibrating sample magnetometer(VSM),*** peaks obtained from the XRD confirmed samples having crystallite(32–36 nm)single phase inverse spinel structure without any traceable *** parameters were calculated from XRD and it increases with Zn *** revealed irregularly shaped grains(-0.5–0.7μm)morphology with heterogeneous *** dielectric constant(ε′)and dielectric loss(tanδ),have been measured as a function of frequency at room *** dependence of ε′ and tan δ with frequency showed the normal dielectric behavior in accordance with the Maxwell-Wagner type of interfacial polarization and electron hopping change between Co^(2+)and Co^(3+)as well as between Fe^(2+)and Fe^(3+)ions at octahedral sites.

关键词： Solgel cobalt ferrite dielectric magnetic properties.

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Comparative studies of elemental composition in leaves and flowers of Catharanthus roseus growing in Bangladesh

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Asian Pacific Journal of Tropical Biomedicine 2016年第1期6卷 50-54页

作者： Shahin Aziz Koushik Saha Nasim Sultana Husna Parvin Nur Md.Aminul Ahsan Shamim Ahmed Md.Kamal Hossain Chemical Research Division BCSIR Department of Chemistry Jahangirnagar University Bangladesh Council of Scientific and Industrial Research (bcsir) laboratories

Objective:To investigate the elemental composition of the leaves and flowers of Catharanthus roseus(***) due to the plant's wide application in the indigenous medicinal system and its chemical constituents' ***:The atomic absorption spectrophotometer was used for quantitative analysis of various ***:Total 13 important elements were analyzed in leaves and flowers of *** indicated the presence of Na,K,Ca,Mg,Cr,Fe,Zn,Al,Cu,Ni,Pb,Cd and Mn in both leaves and *** most important finding of the work was that,leaves of *** showed high concentration of all elements except K and Zn while flowers of *** showed higher concentration of K and ***:The elemental composition in both leaves and flowers of *** were found to be ***,different parts of this medicinal plant are enriched in some micro and macro nutrients like Fe,Ca,Na,K,Zn,which are very important for biological metabolic system as well as human health.

关键词： Bangladesh Catharanthus roseus Indigenous medicinal systems Atomic absorption spectrophotometer Elemental composition

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Medicinal values of aquatic plant genus Nymphoides grown in Asia: A review

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Asian Pacific Journal of Tropical Biomedicine 2018年第2期8卷 113-119页

作者： Zihan Rahman Khan Nargis Sultana Chowdhury Suriya Sharmin Md.Hossain Sohrab Pharmaceutical Sciences Research Division BCSIR Laboratories Department of Pharmacy Manarat International University

Nymphoides is an aquatic genus consisting about 50 species, of which few were accepted as traditional medicinal plants in Asia. The literature review revealed that Nymphoides species are widely used in Ayurvedic medicine as a popular drug, i.e. Tagara. They are also utilized by the traditional local healers of different Asian countries to treat various diseases, like convulsion, jaundice, fever, headache, etc. According to the in vivo and in vitro pharmacological studies, Nymphoides species have been claimed to possess major biological activities like anticonvulsant, antioxidant, hepatoprotective, cytotoxic, antitumor, etc. Biochemical profiling of different aquatic plants of this genus revealed the presence of some important phytochemicals as polyphenolic component, flavonoids, triterpenes, carbohydrates, glycosides, etc. Several valuable bioactive compounds including ephedrine, coumarin, secoiridoid glucosides, methyl quercetin, ferulic acid, foliamenthoic acid, etc. were also known to be isolated and identified from different Nymphoides species. The aim of this review is to analyze the published report based on the medicinal values of different Asian Nymphoides species, to provide the updated information about the ethnomedicinal, pharmacological as well as the phytochemical properties for the first time.

关键词： Nymphoides Aquatic Ayurvedic medicine Phytochemicals

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Comparative Study between the Effect of Momordica charantia(Wild Type) Fruits and Coccinia cordifolia’s Leaf on Hypoglycemic and Hypolipidemic Activities of Alloxan

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Journal of Diabetes Mellitus 2014年第2期4卷 115-123页

作者： Dipa Islam Evena Parvin Lipy Samiur Rahman Liton Chandra Mohanta Khaledun Nahar Babi Animal Research Section Institute of Food Science and Technology Bangladesh Council of Scientific and Industrial Research (BCSIR) Dhaka Bangladesh bcsir laboratories dhaka Bangladesh Council of Scientific and Industrial Research (BCSIR) Dhaka Bangladesh

Aims: The study was aimed to compare the hypoglycemic and hypolipidemic effect of Momordica charantia (wild type) fruits and Coccinia cordifolia’s leaf in alloxan induced type 2 diabetic Long-Evans rats. Methods: All rats were divided into groups A to H (n = 48, 06 rats per group). They were made diabetic by intraperitoneally injecting alloxan monohydrate 150-mg/Kg-body weight. Groups A and B were provided with normal diet and glibenclamide plus normal diet respectively. C to H groups were provided with different percentages (70%, 50% and 30% of regular diet) of samples. Different biochemical parameters (blood glucose level, serum total cholesterol, triglyceride (TG), LDL, HDL, serum insulin, hepatic glycogen) were observed for 21 consecutive days (at eight days interval). Results: Oral administration of both of the Momordica charantia (wild type) fruits and Coccinia cordifolia’s leaf significantly (p nificantly (p level and LDL in type 2 diabetic rats. HDL levels were increased slightly and hepatic glycogen level was more or less unchanged in both groups at 22nd day. Conclusion: Though both samples show hypoglycemic and hypolipidemic activities, 50% wild type fruits of Momordica charantia were more significant

关键词： Diabetics Alloxan Monohydrate Hypoglycemia Hypolipidemia

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Cytotoxic, Antimicrobial and Antioxidant Properties of Commelina diffusaBurm. F.

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Pharmacology & Pharmacy 2019年第2期10卷 82-93页

作者： Mahmuda Nasrin Farhana Afroz Suriya Sharmin Md. Sohel Rana Md. Hossain Sohrab Department of Pharmacy Jahangirnagar University Dhaka Bangladesh Pharmaceutical Sciences Research Division BCSIR Laboratories Dhaka Bangladesh

Commelina diffusa Burm. F. is a herbaceous tropical plant with different traditional medicinal uses. Present study is aimed to isolate the bioactive compounds from DCM-Methanol extract of the powdered whole plant of Commelina diffusa and to investigate the cytotoxic, antimicrobial and antioxidant activities of the crude extract and its twelve vacuum liquid chromatographic fraction (CD1-12). Vacuum Liquid Chromatography (VLC) was employed to isolate bioactive metabolites. The physicochemical properties of the isolated compound were examined and the molecular structure was elucidated by NMR spectroscopy.?Cytotoxic, antibacterial, antioxidant activities were evaluated following brine shrimp lethality bioassay, disc diffusion method and DPPH free radical scavenging assay respectively. The isolated compound was identified as steroid (stigmasterol) which had significant cytotoxic effect on vero cell line. The crude extract and its fractions (CD8-CD12) exhibited strong cytotoxicity in brine shrimp lethality bioassay having LC50 values 3.79, 9.19, 29.49, 16.60, 19.36, 44.58 μg/mL respectively. The crude extract showed mild to strong antibacterial activity. Fractions (CD5-CD12) showed mild to strong antibacterial activity against Escherichia coli in comparison with Kanamycin (standard). Strong antioxidant activities were found in crude extract (IC50 value 30.52 μg/ml), CD11 (IC50 value 39.27 μg/ml) and CD12 (IC50 value 19.50 μg/ml). The study suggests Commelina diffusa plant extract to have strong antioxidant and cytotoxic activity which is indicative of presence of compounds with broad spectrum of curative applications. One compound namely stigmasterol has been isolated from the plant.

关键词： Commelina diffusa Stigmasterol Brine Shrimp Lethality Bioassay Disc Diffusion Method Free Radical Scavenging Assay

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