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Journal of Magnesium and Alloys 2023年第9期11卷 3231-3240页

作者： saeed ahmed State Key Laboratory of Chemical Resource Engineering College of ChemistryBeijing University of Chemical TechnologyBeijing 100029China Department of Chemistry The University of LahoreLahore 54590Pakistan Department of Chemistry University of ChakwalPakistan

In this work, a series of hierarchical flower-like magnesium oxide(MgO) adsorbents were successfully fabricated in a cetyltrimethylammonium bromide(CTAB) assisted solvothermal route using hexamethylenetetramine(HMTA) as a precipitating agent. Effects of CTAB feeding amount on the structure, morphology, pore structure, and corresponding adsorption behavior were investigated. The hierarchical gardenias flower-like MgO demonstrated a surface area of 336.54 m^(2)·g^(-1) at a minimum ratio of the CTAB/Mg^(2+)was 0.02 in the reaction system. The hierarchical MgO phosphate removal capacity was 348.32 mg·g^(-1), which followed the pseudo-second-order and Freundlich isotherm model obtained from the large surface area and appropriate pore size. The value of n also suggests the feasible nature of phosphate adsorption under the examined conditions. Indeed, this CTAB assisted solvothermal method can provide a new understanding to tune the desired properties of a material by merely adjusting the reaction parameters of MgO.

关键词： Adsorption CTAB-assisted Magnesium oxide Phosphate removal Solvothermal

Dependence of effective screening length in granular columns on bead and silo sizes and their ratio

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Chinese Physics B 2013年第5期22卷 591-594页

作者： Abdul Qadir Madad Ali Shah saeed ahmed Khan Department of Electrical Engineering Sukkur Institute of Business Administration

Apparent mass measurements at the bottom of silos have been carried out. An important parameter in the Janssen model known as the effective screening length has been investigated for different bead and silo diameters as well as of their ratios. It is found that the effective screening length augments with the grain diameter d in addition to the granular column size. It is also revealed that λ exhibits stronger correlation with the bead diameter than that of the silo. This phenomenon is attributed to the reduced-shielding of the vertical stresses to the horizontal ones.

关键词： granular systems granular solids static sand piles granular compaction

Ultrasound-assisted Extraction of Anthocyanins to Fabricate pH Sensitive Films for Food Preservation

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Ultrasound-assisted Extraction of Anthocyanins to Fabricate ...

作者： saeed ahmed 四川农业大学

学位级别：硕士

pH sensitive packaging is getting attraction in the food packaging industry because the conditions changing inside the packaging material can be *** increasing demand of safe,secure,and fresh foods has led to the emergence of p H sensitive food *** this study,various natural and biodegradable materials were used for the formation of food packaging.p H packaging films were fabricated using three food-grade anthocyanins（ACNs）.Red cabbage（RC）,Purple sweet potato（PSP）,and Black carrot（BC）ACNs were extracted using the ultrasound assisted extraction（UAE）method and incorporated with polyvinyl alcohol（PVA）,gelatin（GEL）,and chitosan（CS）.The study was conducted in two *** One involved the fabrication of nanofibers via electrospinning technique,while second Phase Two involved the solution casting method of fabrication.A comparison was conducted thoroughly amongst the two *** Phase One,the comparison study amongst all three ACNs antioxidant activity is explained,while in Phase Two,a description is provided on the best p H sensitive films and their effect on packaging and color change after food is *** packaging films were divided into three main ratios 8:1:1,7:2:1,and 6:2:2for PVA/ACNs:GEL:CS,*** morphology of films was evaluated using scanning electron microscopy（SEM）,molecular interactions were studied using Fourier transformed infrared spectroscopy（FTIR）,and thermal properties were studied using Differential scanning calorimetry（DSC）.Mechanical,barrier,and optical properties were also *** results reveal that incorporation GEL thoroughly improved the mechanical strength and moisture content of films,while incorporation of ACNs significantly enhanced the light barrier properties of *** results indicated that BC ACNs are more stable,and thus less susceptible for p H sensitive food packaging.A comparison study was also conducted to evaluate the three *** showed the least activity compared with

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Energy-Efficient Scheduling for a Cognitive IoT-Based Early Warning System

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Computers, Materials & Continua 2022年第6期71卷 5061-5082页

作者： saeed ahmed Noor Gul Jahangir Khan Junsu Kim Su Min Kim Department of Electronics Engineering Korea Polytechnic UniversitySiheung15073Korea Mirpur University of Science and Technology Mirpur10250Pakistan Department of Electronics University of PeshawarPeshawar25120Pakistan Sarhad University of Science and Information Technology Peshawar25000Pakistan

Flash floods are deemed the most fatal and disastrous natural hazards globally due to their prompt onset that requires a short prime time for emergency *** Internet of things(CIoT)technologies including inherent characteristics of cognitive radio(CR)are potential candidates to develop a monitoring and early warning system(MEWS)that helps in efficiently utilizing the short response time to save lives during flash ***,most CIoT devices are battery-limited and thus,it reduces the lifetime of the *** tackle these problems,we propose a CIoTbased MEWS to slash the fatalities of flash *** extend the lifetime of the MEWS by conserving the limited battery energy of CIoT sensors,we formulate a resource assignment problem for maximizing energy *** solve the problem,at first,we devise a polynomial-time heuristic energyefficient scheduler(EES-1).However,its performance can be unsatisfactory since it requires an exhaustive search to find local optimum values without consideration of the overall network energy *** enhance the energy efficiency of the proposed EES-1 scheme,we additionally formulate an optimization problem based on a maximum weight matching bipartite ***,we additionally propose a Hungarian algorithm-based energy-efficient scheduler(EES-2),solvable in polynomial *** simulation results show that the proposed EES-2 scheme achieves considerably high energy efficiency in the CIoT-based MEWS,leading to the extended lifetime of the MEWS without loss of throughput performance.

关键词： Flash floods internet of things cognitive radio early warning system network lifetime energy efficiency

Optimal Cooperative Spectrum Sensing Based on Butterfly Optimization Algorithm

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Computers, Materials & Continua 2022年第4期71卷 369-387页

作者： Noor Gul saeed ahmed Atif Elahi Su Min Kim Junsu Kim Department of Electronics Engineering Korea Polytechnic University15073Gyeonggi-doKorea Department of Electronics University of Peshawar25120Pakistan Department of Electrical Engineering Mirpur University of Science of TechnologyAJ&K10250Pakistan Department of Electrical Engineering International Islamic UniversityIslamabad 44000Pakistan

Since the introduction of the Internet of Things(IoT),several researchers have been exploring its productivity to utilize and organize the spectrum *** radio(CR)technology is characterized as the best aspirant for wireless communications to augment IoT *** the CR networks,secondary users(SUs)opportunistically get access to the primary users(PUs)spectrum through spectrum *** multipath issues in the wireless channel can fluster the sensing ability of the individual ***,several cooperative SUs are engaged in cooperative spectrum sensing(CSS)to ensure reliable sensing *** CSS,security is still a major concern for the researchers to safeguard the fusion center(FC)against abnormal sensing reports initiated by the malicious users(MUs).In this paper,butterfly optimization algorithm(BOA)-based soft decision method is proposed to find an optimized weighting coefficient vector correlated to the SUs sensing *** coefficient vector is utilized in the soft decision rule at the FC before making any global *** effectiveness of the proposed scheme is compared for a variety of parameters with existing schemes through simulation *** results confirmed the supremacy of the proposed BOA scheme in both the normal SUs’environment and when lower and higher SNRs information is carried by the different categories of MUs.

关键词： Internet of Things cognitive radio network butterfly optimization algorithm particle swarm optimization malicious users genetic algorithm

Facile formation of hierarchical magnesium silicate hydrate microspheres as an adsorbent for the textile dyes

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Particuology 2024年第10期93卷 99-110页

作者： Tin Kyawoo Naveed Karim Chao Jiang saeed ahmed Weiliang Tian Huiyu Li Yongjun Feng State Key Laboratory of Chemical Resource Engineering Beijing Engineering Center for Hierarchical CatalystsBeijing University of Chemical TechnologyBeijing100029China Department of Chemistry The University of ChakwalChakwal48800Pakistan College of Chemistry and Chemical Engineering Tarim UniversityAlar843300China

Hierarchical porous magnesium silicate hydrate (MSH) microspheres composed of sheets are successfully developed under facile conditions using a hard template. The role of hexadecyltrimethylammonium bromide (CTAB) on the formation and adsorption behavior was also observed for the methyl orange and methylene blue. The formed MSH possesses a surface area of 453.24 m^(2)/g, an average pore size of 6.38 nm, and a pore volume of 0.75 cm^(3)/g without CTAB. Based on the role of CTAB and the change in the ratio of Mg/Si, the MSH retained its sphere-like structure with a variation in pore parameters. The formed MSH was used as an adsorbent to remove methylene blue and methyl orange. The pseudo-second-order kinetic and Langmuir Isotherm models are well-fitted, with a 256.4 mg/g removal capacity and 84.2 mg/g for methylene blue and methyl orange, respectively. The modified MSH with CTAB played a positive role for the methyl orange and a negative role for the methylene blue regarding removal performance.

关键词： Adsorption Hierarchical microspheres Magnesium silicate Methyl orange Methylene blue Surfacemodification

Reconfigurable Sensing Time in Cooperative Cognitive Network Using Machine Learning

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Computers, Materials & Continua 2023年第3期74卷 5209-5227页

作者： Noor Gul saeed ahmed Su Min Kim Muhammad Sajjad Khan Junsu Kim Department of Electronics Engineering Korea Polytechnic UniversityGyeonggi-do15073Korea Department of Electronics University of PeshawarPeshawar25120Pakistan Deparment of Electrical Engineering Mirpur University of Science of TechnologyAJ&KMirpur10250Pakistan Department of Electrical Engineering International Islamic UniversityIslamabad44000Pakistan

A cognitive radio network(CRN)intelligently utilizes the available spectral resources by sensing and learning from the radio environment to maximize spectrum *** CRNs,the secondary users(SUs)opportunistically access the primary users(PUs)***,unambiguous detection of the PU channel occupancy is the most critical aspect of the operations of *** spectrum sensing(CSS)is rated as the best choice for making reliable sensing *** paper employs machinelearning tools to sense the PU channels reliably in *** sensing parameters are reconfigured to maximize the spectrum utilization while reducing sensing error and cost with improved channel *** fine-k-nearest neighbor algorithm(FKNN),employed in this paper,estimates the number of samples based on the nature of the channel under-specific detection and false alarm probability *** simulation results reveal that the sensing cost is suppressed by reducing the sensing time and exploiting the traditional fusion rules,validating the effectiveness of the proposed ***,the global decision made at the fusion center(FC)based on the modified sensing samples,results low energy consumption,higher throughput,and improved detection with low error probabilities.

关键词： Energy detection machine learning k-nearest-neighbor decision tree linear regression throughput energy consumption

Highly efficient and stable electrooxidation of methanol and ethanol on 3D Pt catalyst by thermal decomposition of In2O3 nanoshells

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Journal of Energy Chemistry 2017年第1期26卷 193-199页

作者： Yuhang Xie Hulin Zhang Guang Yao saeed ahmed Khan Xiaojing Cui Min Gao Yuan Lin State Key Laboratory of Electronic Thin Film and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 610054SichuanChina Center for Information in Medicine University of Electronic Science and Technology of ChinaChengdu 610054SichuanChina The First Sub-Institute Nuclear Power Institute of ChinaChengdu 610041SichuanChina

In this paper In2O3nanoshells have been synthesized via a facile hydrothermal approach. The nanoshells can be completely cracked into pony-size nanocubes by annealing, which are then used as a support of Pt catalyst for methanol and ethanol electrocatalytic oxidation. The prepared In2O3and supported Pt catalysts (Pt/In2O3) were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), field effect scanning electron microscopy (FESEM), and transmission electron microscopy (TEM). Cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry and electrochemical impedance spectroscopy (EIS) were carried out, indicating the excellent catalytic performance for alcohol electrooxidation can be achieved on Pt/In2O3nanocatalysts due to the multiple active sites, high conductivity and a mass of microchannels and micropores for reactant diffusions arising from 3D frame structures compared with that on the Pt/C catalysts. © 2016 Science Press

关键词： Alcohols Catalyst activity Catalysts Chronoamperometry Cyclic voltammetry Decomposition Electrocatalysis Electrochemical impedance spectroscopy Electron microscopy Electrooxidation Energy dispersive spectroscopy Ethanol High resolution transmission electron microscopy Methanol Nanoshells Nanostructured materials Nanostructures Platinum Scanning electron microscopy Transmission electron microscopy X ray diffraction X ray photoelectron spectroscopy X ray spectroscopy

Fentanyl and xylazine crisis:Crafting coherent strategies for opioid overdose prevention

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World Journal of Psychiatry 2024年第6期14卷 760-766页

作者： Lakshit Jain Jasleen Kaur Shahana Ayub Danya Ansari Rizwan ahmed Abdul Qadir Dada saeed ahmed Department of Psychiatry University of ConnecticutFarmingtonCT 06032United States Addiction Services Division Connecticut Valley HospitalMiddletownCT 06457United States Department of Psychiatry Institute of LivingHartfordCT 06102United States Department of Medicine Islamabad Medical and Dental CollegeIslamabad 44000Pakistan Department of Medicine Liaquat College of Medicine and DentistryKarachi 75290Pakistan Department of Medicine Trinity School of MedicineRoswellGA 30075United States Addiction Services and Dual Diagnosis Unit Saint Francis Hospital and Medical CenterHartfordCT 06105United States

The United States is in the throes of a severe opioid overdose epidemic,primarily fueled by the pervasive use of fentanyl and the emerging threat of xylazine,a veterinary sedative often mixed with *** high potency and long duration of fentanyl is compounded by the added risks from xylazine,heightening the lethal danger faced by opioid *** such as enhanced surveillance,public awareness campaigns,and the distribution of fentanylxylazine test kits,and naloxone have been undertaken to mitigate this ***-related overdose deaths persist despite these efforts,partly due to inconsistent policies across states and resistance towards adopting harm reduction strategies.A multifaceted approach is imperative in effectively combating the opioid overdose *** approach should include expansion of treatment access,broadening the availability of medications for opioid use disorder,implementation of harm reduction strategies,and enaction of legislative reforms and diminishing stigma associated with opioid use disorder.

关键词： Fentanyl Xylazine Opioid overdose Epidemic Opioid use disorder Buprenorphine Medications for opioid use disorder

MWCNTs based flexible and stretchable strain sensors

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Journal of Semiconductors 2017年第5期38卷 18-23页

作者： saeed ahmed Khan Min Gao Yuechang Zhu Zhuocheng Yan Yuan Lin State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China

Carbon nanotubes have potential applications in flexible and stretchable devices due to their remarkable electromechanical *** and stretchable strain sensors of multi-walled carbon nanotubes（MWCNTs）with aligned or random structures were fabricated on poly-dimethylsiloxane（PDMS） substrate with different *** was observed that the spraycoatedtechniquebased strain sensor fabricated on PDMS substrate showed higher sensitivity higher stretchability,better linearity and excellent longer time stability than the sensor fabricated with other methods presented in this *** scanning electron microscopy images indicated the spray coating technique can produce a better uniform and compact CNT network,which is the important role affecting the performance of CNT-based flexible strain sensors.

关键词： strain sensor stretchable sensor carbon nanotube arrays