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Assessment of ecological risk for heavy metals in surface sediment of an urban river in a developing country

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International Journal of Sediment Research 2023年第6期38卷 834-846页

作者： md Saiful islam md Humayun Kabir mir mohammad Ali md Towhidul islam Asfia Niger md Humayun Kabir Zulhilmi Ismail Sujat Ahmed Khalid A.ibrahim Abubakr m.Idris Department of Soil Science Patuakhali Science and Technology University Department of Environmental Science and Resource management Mawlana Bhashani Science and Technology University Department of Aquaculture Sher-e-Bangla Agricultural University Department of Soil Science Bangabandhu Sheikh Mujibur Rahman Agricultural University Centre for River and Coastal Engineering(CRCE) Universiti Teknologi Malaysia(UTM) Department of Water & Environmental Engineering Faculty of Civil EngineeringUniversiti Teknologi Malaysia(UTM) Environment Center for People & Environ(CPE) Department of Biology College of ScienceKing Khalid University Center for Environment and Tourism Studies and Research King Khalid University Department of Chemistry College of ScienceKing Khalid University Research Center for Advanced materials Science(RCAmS) King Khalid University

The speed of increasing threats to the riverine water resources makes it more critical to protect the health of Old Brahmaputra River *** current study was done to investigate the concentrations,distributions,sources,and ecological risk of heavy metals in surface sediment from the Old Brahmaputra River,*** were collected from seven sites and analyzed with an inductively coupled plasma-mass spectrometer(ICP-mS).The results showed that mean concentrations(mg/kg) of heavy metals were in the order of nickel(Ni)(44.69)> chromium(Cr)(30.16)> lead(Pb)(19.31)>copper(Cu)(17.84)> cadmium(Cd)(3.94)> arsenic(As)(2.73).The contamination factor(CF),pollution load index(PLI),enrichment factor(EF),and geo-accumulation index(Igeo) indicated low to moderate *** unit analysis revealed that the studied metals from all stations posed low *** sediment of the study river was uncontaminated to moderately contaminated,posing a minimal ecological ***,Cr,Ni,and Pb originated from anthropogenic sources rather than geogenic sources,and caused the severity of *** this regard,pollutant-based intensive monitoring of heavy metals and holistic ecological risk assessments are required to maintain a sound and healthy aquatic environment in the river.

关键词： Heavy metals Sediment quality Ecological risk Old Brahmaputra river Source identification

Impact of grazing on soil, vegetation and ewe production performances in a semi-arid rangeland

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Journal of mountain Science 2018年第4期15卷 685-694页

作者： muhammad islam Abdul RAZZAQ Shamim GUL Sarfraz AHmAD Taj mUHAmmAD Sawsan HASSAN Barbara RISCHKOWSKY m.N.m.ibrahim mounir LOUHAICHI International Center for Agricultural Research in Dry Areas (ICARDA) South Asia Islamabad Pakistan Animal Sciences Division Pakistan Agricultural Research Council Islamabad Pakistan Botany Department University of Balochistan Quetta Pakistan Department of Natural Resource Sciences McGill University QC Canada Natural Resources Division Pakistan Agricultural Research Council Islamabad Pakistan Forest & Wildlife Department Quetta Balochistan Pakistan International Center for Agricultural Research in Dry Areas (ICARDA) Amman Jordan International Center for Agricultural Research in Dry Areas (ICARDA) SSA ILRI campus Addis Ababa Ethiopia International Livestock Research Institute (ILRI) Pakistan

Controlled grazing is considered a good management strategy to maintain or increase the live weight of livestock and to reduce vegetation degradation of rangelands. The present study investigated soil characteristics, aboveground vegetation biomass dynamics and controlled grazinginduced changes in the live weight of local ewes in the semi-arid rangeland of Ahmadun, Ziarat, Balochistanprovince of Pakistan. An area of 115 ha was protected from livestock grazing in April 2014. In June 2015, soil characteristics within 0-30 cm depth i.e. soil organic matter(SOm), mineral nitrogen, p H and texture in controlled and uncontrolled grazing sites were assessed. Aboveground vegetation biomass measured in early(June) and late summer(August) in 2015 and 2016. The nutritional value i.e. crude protein, phosphorus(P), neutral detergent fiber(NDF), acid detergent fiber(ADF), calcium(Ca), magnesium(mg) and potassium(K) of dominantplant species were assessed at the beginning of experiment in 2015. Vegetation cover of controlled and uncontrolled grazing sites was also measured during the two years of the study period using the Veg measure software. From June to November in2015 and 2016, controlled and uncontrolled livestock grazing sites were grazed on a daily basis by local ewes with a stocking rate of 2 and 1 head ha^(-1) respectively. Results reveal that the organic matter contents of coarse-textured, slightly alkaline soil of the study site were in the range of 9.4-17.6 g kg^(-1) soil and showed a strong positive correlation with aboveground vegetation biomass. The biomass of plants was 56.5% and 33% greater at controlled than uncontrolled grazing site in 2015 and 2016 respectively and plant cover was also higher at controlled than uncontrolled grazing site in both years The nutrient contents were significantly(Pmpared to the uncontrolled *** results

关键词： Grazing exclosure Soil organic matter Vegetation cover Vegmeasure

Fe doping promoted electrocatalytic N2 reduction reaction of 2H moS2

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Chinese Chemical Letters 2020年第9期31卷 2487-2490页

作者： Jiaojiao Guo Tsegaye Tadesse Tsega ibrahim Ul islam Asma Iqbal Jiantao Zai Xuefeng Qian School of Chemistry and Chemical Engineering and State Key Laboratory of metal matrix Composites Shanghai Jiao Tong UniversityShanghai 200240China

Electrocatalytic N2 reduction to ammonia is a fascinating alternative to Haber-Bosch process and also considered as an energy sto rage *** work,Fe doped moS2/carbon cloth(CC) has been studied on the electro-catalysis fix nitrogen indicating the doped Fe can indeed enhance the moS2 material *** with moS2/CC,Fe-mo-S-3/CC not only increases 10 times in the rate of production ammonia,but also 5 times in Faraday efficiency.

关键词： 2H moS2 Electrocatalytic N2 reduction reaction(NRR) Fe doping Ammonia

Adaptive Power Control Aware Depth Routing in Underwater Sensor Networks

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Computers, materials & Continua 2021年第10期69卷 1301-1322页

作者： Ghufran Ahmed Saiful islam Ihsan Ali Isra Adil Hayder Abdelmuttlib ibrahim Abdalla Ahmed muhammad Talha Sultan S.Alshamrani Ag Asri Ag ibrahim Department of Computer Science FAST National University of Computer and Emerging Sciences(NUCES)KarachiPakistan Dr.A.Q.Khan Institute of Computer Sciences and Information Technology KahutaPakistan Faculty of Computer Science and Information Technology University of MalayaKuala Lumpur50603Malaysia Department of Computer Science COMSATS University IslamabadIslamabadPakistan Deanship of Scientific Research King Saud UniversityRiyadhSaudi Arabia Department of Information Technology College of Computer and Information TechnologyTaif UniversityTaif21944Saudi Arabia Faculty of Computing and Informatics Universiti Malaysia SabahKota KinabaluSabahMalaysia

Underwater acoustic sensor network(UASN)refers to a procedure that promotes a broad spectrum of aquatic *** can be practically applied in seismic checking,ocean mine identification,resource exploration,pollution checking,and disaster *** confronts many difficulties and issues,such as low bandwidth,node movements,propagation delay,3D arrangement,energy limitation,and high-cost production and arrangement costs caused by antagonistic underwater *** wireless sensor networks(UWSNs)are considered a major issue being encountered in energy management because of the limited battery power of their ***,the harsh underwater environment requires vendors to design and deploy energy-hungry devices to fulfil the communication requirements and maintain an acceptable quality of ***,increased transmission power levels result in higher channel interference,thereby increasing packet *** the facts mentioned above,this research presents a controlled transmission power-based sparsity-aware energy-efficient clustering in *** contributions of this technique is ***,it uses the adaptive power control mechanism to utilize the sensor nodes’battery and reduce channel interference ***,thresholds are defined to ensure successful ***,clustering can be implemented in dense areas to decrease the repetitive transmission that ultimately affects the energy consumption of nodes and interference ***,mobile sinks are deployed to gather information locally to achieve the previously mentioned *** suggested protocol is meticulously examined through extensive simulations and is validated through comparison with other advanced UWSN *** show that the suggested protocol outperforms other procedures in terms of network lifetime and packet delivery ratio.

关键词： UWSNs UASNs QoS

mechanical and thermodynamical stability of BiVO4 polymorphs using first-principles study

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Chinese Physics B 2017年第3期26卷 395-403页

作者： A K m Farid UI islam md Nurul Huda Liton H m Tariqul islam md Al Helal md Kamruzzaman Department of Computer Science and Engineering Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Physics Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Chemistry Begum Rokeya University Rangpur Rangpur-5400 Bangladesh Department of Physics and materials Science and Center of Super-Diamond and Advanced Films (COSDAF) City University of Hong Kong Hong Kong SAR China

First principles calculations of structural, electronic, mechanical, and thermodynamic properties of different poly- morphs of BiVO4 are performed using Bender-type plane/wave ultrasoft pseudopotentials within the generalized gradient approximation （GGA） in the flame of density functional theory （DFT）. The calculated structural and electronic properties are consistent with the previous theoretical and experimental results. The electronic structures reveal that m-BiVO4, op- BiVO4, and st-BiVO4 have indirect band gaps, on the other hand, zt-BiVO4 has a direct band gap. From the DOS and mulliken＇s charge analysis, it is observed that only m-BiVO4 has 6s2 Bi lone pair. Bond population analysis indicates that st-BiVO4 shows a more ionic nature and a similar result is obtained from the elastic properties. From the elastic prop- erties, it is observed that st-BiVO4 is more mechanically stable than the others, st-BiVO4 is more ductile and useful for high electro-optical and electro-mechanical coupling devices. Our calculated thermodynamic properties confirm the similar characteristics found from electronic and elastic properties, m-BiVO4 is useful as photocatalysts, solid state electrolyte, and electrode and other polymorphs are applicable in electronic device fabrications.

关键词： BiVO4 crystal structure lone pair mechanical stability

New ternary superconducting compound LaRu2As2： Physical properties from density functional theory calculations

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Chinese Physics B 2017年第3期26卷 453-460页

作者： m A Hadi m S Ali S H Naqib A K m A islam Department of Physics University of Rajshahi Rajshahi 6205 Bangladesh Department of Physics Pabna University of Science and Technology Pabna 6600 Bangladesh International islamic University Chittagong Chittagong 4203 Bangladesh

In this paper, we perform the density functional theory （DFT） -based calculations by the first-principles pseudopo- tential method to investigate the physical properties of the newly discovered superconductor LaRu2As2 for the first time. The optimized structural parameters are in good agreement with the experimental results. The calculated independent elas- tic constants ensure the mechanical stability of the compound. The calculated Cauchy pressure, Pugh＇s ratio as well as Poisson＇s ratio indicate that LaRu2As2 should behave as a ductile material. Due to low Debye temperature, LaRu2As2 may be used as a thermal barrier coating （TBC） material. The new compound should exhibit metallic nature as its valence bands overlap considerably with the conduction bands. LaRu2As2 is expected to be a soft material and easily machinable because of its low hardness value of 6.8 GPa. The multi-band nature is observed in the calculated Fermi surface. A highly anisotropic combination of ionic, covalent and metallic interactions is expected to be in accordance with charge density calculation.

关键词： new superconductor LaRu2As2 density functional theory (DFT) calculations mechanical proper-ties electronic features

multi-level supervisory emergency control for operation of remote area microgrid clusters

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Journal of modern Power Systems and Clean Energy 2019年第5期7卷 1210-1228页

作者： munira BATOOL Farhad SHAHNIA Syed m.islam School of Electrical Engineering Computing and Mathematical SciencesCurtin UniversityPerthAustralia School of Engineering and Information Technology Murdoch UniversityPerthAustralia School of Science Engineering and Information TechnologyFederation UniversityBallaratAustralia

Remote and regional areas are usually supplied by isolated and self-sufficient electricity systems,which are called as microgrids(mGs).To reduce the overall cost of electricity production,mGs rely on non-dispatchable renewable *** such as overloading or excessive generation by renewable sources can result in a substantial voltage or frequency deviation in *** paper presents a supervisory controller for such *** key idea is to remedy the emergencies by optimal internal or external support.A multi-level controller with soft,intermedial and hard actions is *** soft actions include the adjustment of the droop parameters of the sources and the controlling of the charge/discharge of energy *** intermedial action is exchanging power with neighboring mGs,which is highly probable in large remote *** the last remedying resort,curtailing loads or renewable sources are assumed as hard *** proposed controller employs an optimization technique consisting of certain objectives such as reducing power loss in the tie-lines amongst mGs and the dependency of an mG to other mGs,as well as enhancing the contribution of renewable sources in electricity *** of the fuel consumption and emissions of conventional generators,along with frequency and voltage deviation,is the other desired *** performance of the proposal is evaluated by several numerical analyses in mATLAB~?.

关键词： microgrids Emergency controller Optimization Remote area

Band structure,Fermi surface,elastic,thermodynamic,and optical properties of AlZr3,AlCu3,and AlCu2Zr:First-principles study

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Chinese Physics B 2016年第8期25卷 103-112页

作者： Parvin R Parvin F Ali m S islam A K m A Department of Physics Rajshahi University Rajshahi-6205 Bangladesh Department of Physics Pabna University of Science and Technology Pabna 6600 Bangladesh International islamic University Chittagong 154/A College Road Chittagong-4203 Bangladesh

The electronic properties（Fermi surface,band structure,and density of states（DOS）） of Al-based alloys Alm3（m=Zr and Cu） and AlCu2Zr are investigated using the first-principles pseudopotential plane wave method within the generalized gradient approximation（GGA）.The structural parameters and elastic constants are evaluated and compared with other available ***,the pressure dependences of mechanical properties of the compounds are *** temperature dependence of adiabatic bulk modulus,Debye temperature,specific heat,thermal expansion coefficient,entropy,and internal energy are all obtained for the first time through quasi-harmonic Debye model with phononic effects for T = 0 K-100 *** parameters of optical properties（dielectric functions,refractive index,extinction coefficient,absorption spectrum,conductivity,energy-loss spectrum,and reflectivity） of the compounds are calculated and discussed for the first *** reflectivities of the materials are quite high in the IR-visible-UV region up to ~ 15 eV,showing that they promise to be good coating materials to avoid solar *** of the properties are also compared with those of the Al-based Ni3 Al compound.

关键词： first principle calculations Fermi surface elastic moduli entropy and internal energy optical properties

Determination of volatile organic compounds in river water by solid phase extraction and gas chromatography

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Journal of Environmental Sciences 2004年第3期16卷 497-501页

作者： m.A.mottaleb m.Z.Abedin m.S.islam Department of Chemistry Department of Chemical Technology and Polymer SciencesDepartment of Chemical Technology and Polymer Sciences University of RajshahiRajshahi 6205 BangladeshDept.of Chemistry and BiochemistryBaylor UniversityWacoUSAShahjalal University of Science and TechnologySylhet 3114BangladeshShahjalal University of Science and TechnologySylhet 3114Bangladesh

A simple, rapid, and reproducible method is described employing solid phase extraction(SPE) using dichloromethane followed by gas chromatography(GC) with flame ionization detection(FID) for determination of volatile organic compound(VOC) from the Buriganga River water of Bangladesh. The method was applied to detect the benzene, toluene, ethylbenzene, xylene and cumene(BTEXC) in the sample collected from the surface or 15 cm depth of water. Two hundred ml of n hexane pretreated and filtered water samples were applied directly to a C 18 SPE column. BTEXC were extracted with dichloromethane and average concentrations were obtained as 0 104 to 0 372 μg/ml. The highest concentration of benzene was found as 0 372 μg/ml with a relative standard deviation(RSD) of 6 2%, and cumene was not detected. Factors influencing SPE e.g., adsorbent types, sample load volume, eluting solvent, headspace and temperatures, were investigated. A cartridge containing a C 18 adsorbent and using dichloromethane gave better performance for extraction of BTEXC from water. Average recoveries exceeding 90% could be achieved for cumene at 4℃ with a 2 7% RSD.

关键词： solid phase extraction river water environmental analysis VOC recoveries