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Journal of Thermal Science 2022年第6期31卷 2171-2177页

作者： KHAN Taj Wali qamar ihtzaz Department of Aeronautics and Astronautics Institute of Space TechnologyIslamabad 44000Pakistan

Design, development, and testing of LPRE(Liquid Propellant Rocket Engine) are difficult and expensive tasks. Prior to full-scale design, it is indispensable to optimize important parameters at sub-scale. Propellants flow rates are low for a sub-scale or laboratory scale combustion chambers. It is hard to satisfy chamber cooling and chill feed lines quickly with low flow rates of propellants. This paper proposes a detailed procedure for testing of a laboratory scale semi-cryogenic combustion chamber. Many tests were conducted with a small scale adjustable length combustion chamber. The injection head of the chamber was interchangeable. Liquid-liquid pressure swirl injector and like impinging injectors were used with two different injection heads. Liquid oxygen and kerosene were used as oxidizer and fuel, respectively. Oxidizer to fuel mixing ratio was 0.29-0.45 and the total propellant mass flow rate was 0.06-0.1 kg/s. Problems were faced during testing, including, explosion in the combustion chamber, fuel injector blockage, unstable combustion, incomplete chilling and blockage of cooling water channel, etc. A detailed procedure is designed on the basis of the lessons learned which was experimentally proved.

关键词： LPRE cryogenic testing procedure combustion chamber

Implications of electrode modifications in aqueous organic redox flow batteries

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Journal of Energy Chemistry 2024年第8期95卷 499-510,I0011页

作者： Zahid Manzoor Bhat Mohammad Furquan Muhammad Aurang Zeb Gul Sial Umair Alam Atif Saeed Alzahrani Mohammad qamar Interdisciplinary Research Center for Hydrogen Technologies and Carbon Management(IRC-HTCM) King Fahd University of Petroleum&Minerals(KFUPM)Dhahran 31261Saudi Arabia Department of Materials Science and Engineering King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Interdisciplinary Research Center for Sustainable Energy Systems(IRC-SES) King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

Aqueous organic redox flow batteries(RFBs)exhibit favorable characteristics,such as tunability,multielectron transfer capability,and stability of the redox active molecules utilized as anolytes and catholytes,making them very viable contenders for large-scale grid storage *** attention has been paid on the development of efficient redox-active molecules and their performance optimization through chemical substitutions at various places on the backbone as part of the pursuit for high-performance *** the fact that electrodes are vital to optimal performance,they have not garnered significant *** research has been conducted on the effects of electrode modifications to improve the performance of *** primary emphasis has been given on the impact of electrode engineering to augment the efficiency of aqueous organic *** overview of electron transfer at the electrode-electrolyte interface is *** implications of electrode modification on the performance of redox flow batteries,with a particular focus on the anodic and cathodic half-cells separately,are then *** each section,significant discrepancies surrounding the effects of electrode engineering are thoroughly examined and ***,we have presented a comprehensive assessment along with our perspectives on the future trajectory.

关键词： Redox flow batteries Electrode modification Organic redox molecules Outer sphere and inner sphere

A Novel Approach to Energy Optimization:Efficient Path Selection in Wireless Sensor Networks with Hybrid ANN

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Computers, Materials & Continua 2024年第5期79卷 2945-2970页

作者： Muhammad Salman qamar Ihsan ulHaq Amil Daraz Atif MAlamri Salman A.AlQahtani Muhammad Fahad Munir Department of Electrical and Computer Engineering International Islamic UniversityIslamabad44000Pakistan School of Information Science and Engineering NingboTech UniversityNingbo315100China Software Engineering Department College of Computer and Information SciencesKing Saud UniversityRiyadh11495Saudi Arabia Computer Engineering Department College of Computer and Information SciencesKing Saud UniversityRiyadh11495Saudi Arabia

In pursuit of enhancing the Wireless Sensor Networks(WSNs)energy efficiency and operational lifespan,this paper delves into the domain of energy-efficient routing ***,the limited energy resources of Sensor Nodes(SNs)are a big challenge for ensuring their efficient and reliable *** data gathering involves the utilization of a mobile sink(MS)to mitigate the energy consumption problem through periodic network *** mobile sink(MS)strategy minimizes energy consumption and latency by visiting the fewest nodes or predetermined locations called rendezvous points(RPs)instead of all cluster heads(CHs).CHs subsequently transmit packets to neighboring *** unique determination of this study is the shortest path to reach *** the mobile sink(MS)concept has emerged as a promising solution to the energy consumption problem in WSNs,caused by multi-hop data collection with static *** this study,we proposed two novel hybrid algorithms,namely“ Reduced k-means based on Artificial Neural Network”(RkM-ANN)and“Delay Bound Reduced kmeans with ANN”(DBRkM-ANN)for designing a fast,efficient,and most proficient MS path depending upon rendezvous points(RPs).The first algorithm optimizes the MS’s latency,while the second considers the designing of delay-bound paths,also defined as the number of paths with delay over bound for the *** methods use a weight function and k-means clustering to choose RPs in a way that maximizes efficiency and guarantees network-wide *** addition,a method of using MS scheduling for efficient data collection is *** simulations and comparisons to several existing algorithms have shown the effectiveness of the suggested methodologies over a wide range of performance indicators.

关键词： Wireless Sensor Networks(WSNs) mobile sink(MS) rendezvous point(RP) machine learning Artificial Neural Networks(ANNs)

Dinitrophenyl-oxadiazole compounds:Design strategy,synthesis,and properties of a series of new melt-cast explosives

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Defence Technology（防务技术） 2024年第5期35卷 100-107页

作者： Bao-long Kuang Ting-wei Wang Cong Li Mou Sun qamar-un-Nisa Tariq Chao Zhang Zhi-ming Xie Zu-jia Lu Jian-guo Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China Wuzhou Engineering Group CO. LTD.Beijing 100053China

Melt-cast explosives are the most widely used energetic materials in military composite explosives,researchers have been unremittingly exploring high-energy and insensitive melt-cast *** this work,a series of dinitrophenyl-oxadiazole compounds were designed and *** compounds have an ideal low melting point(80-97℃),good detonation performance(detonation velocity D=6455-6971 m/s,detonation pressure P=18-19 GPa)and extreme insensitive nature(impact sensitivity≥60 J,friction sensitivity>360 N).All these compounds were well characterized by nuclear magnetic resonance,fourier transform infrared spectroscopy,elemental *** 2,3 were unambiguously confirmed by X-ray single crystal diffraction *** a result,their overall properties are superior to traditional melt-cast explosives trinitrotoluene(TNT)and dinitroanisole(DNAN)which may have excellent potential applications in insensitive melt-cast explosives.

关键词： Dinitrophenyl-oxadiazole Melt-cast explosive Low sensitivity

Petrology and Petrographic Delineation of Kamlial Formation Sandstone Mong and Thorar Village, Northern Pakistan

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Journal of Geoscience and Environment Protection 2024年第5期12卷 302-324页

作者： Ehtisham Mehmood Haishen Lv Pei Gao Soban qamar The National Key Laboratory of Water Disaster Prevention College of Hydrology and Water Resources Hohai University Nanjing China College of Mechanical and Petroleum Engineering University of Engineering and Technology Taxila Pakistan

The origin of sandstone in the Rawalpindi group is disputed because of the lesser Himalayas complicated geological structure and ongoing tectonic activity. The goal of the study is to learn more about the petrographic and geological aspects of the Siwalik molasses deposits, which are formations that belong to the same age group. The Early Miocene Kamlial Formation, the Middle to Late Miocene Chinji Formation, and the Late Miocene Nagri Formation are the stratigraphic units revealed in the project area. The texture of the sandstone found in the Rawalpindi Group and Siwalik is fine to medium-grained. The hue ranges from grey to greenish grey. The sandstone displays thin to medium-bedded layers and exhibits thin lamination throughout. The sandstone of the Kamlial Formation contains load casts, potholes, worm burrows, hematite layers, and filled and unfilled mud cracks in basic structures. Model petrographic research reveals that the Murree Formation primarily consists of light minerals like feldspar, quartzite, and felice, whereas the Kamlial Formation is composed of heavy minerals like garnet and tourmaline. Sandstone from the Rawalpindi group undergoes analysis to ascertain its provenance using the quartz feldspar lithic fragments ternary diagram technique. Each plot in the QFL diagram’s recycled orogeny provenance field is plotted.

关键词： Hazara Kashmir Syntaxis Rawalpindi Group Siwalik Group Himalayas Neogene

Combined Application of Biostimulants and EDTA Improved Wheat Productivity under Cadmium Stress

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1647-1665页

作者： Abida Aziz Shafiqa Bano Mubshar Hussain Muhammad Farooq Azhar Ghulam Yasin Naila Hadayat Iqra Arooj Abeer Hashem Ajay Kumar Elsayed Fathi Abd_Allah qamar uz Zaman Department of Botany The Women UniversityMultan54500Pakistan Institute of Agronomy Bahauddin Zakariya UniversityMultan60800Pakistan Department of Forestry and Range Management Bahauddin Zakariya UniversityMultan60800Pakistan Department of Botany Division of Science&TechnologyUniversity of EducationLahore54770Pakistan Department of Microbiology&Molecular Genetics The Women UniversityMultan54500Pakistan Botany and Microbiology Department College of ScienceKing Saud UniversityRiyadh201313Saudi Arabia Amity Institute of Biotechnology Amity UniversityNoida201313India Plant Production Department College of Food and Agricultural SciencesKing Saud UniversityRiyadh11451Saudi Arabia School of Agriculture Yunnan UniversityKunmingYunan650504China Department of Environmental Sciences The University of LahoreLahore54590Pakistan

Wheat(Triticum aestivum L.)exhibits a greater capacity for cadmium(Cd)absorption compared to other cereal crops,leading to elevated daily Cd intake,and posing a signiﬁcant threat to public *** the mitigation of Cd stress in sustainable and environmentally friendly way,a pot study was designed by using exogenous application of various biostimulants,i.e.,Nigella sativa and Ocimum sanctum extracts:0%,10%,and 20%in combination with the chelating agent ethylenediaminetetraacetic acid(EDTA)using 0 and 5 mg kg^(-1) under various levels of Cd stress(i.e.,0,5,10,and 15 mg kg^(-1) soil).Results revealed that Cd stress signiﬁcantly reduced the seed emergence,growth,root,and allometric characters and yield-related parameters of wheat *** most observable reduc-tion was documented in wheat plants exposed to a higher Cd concentration(15 mg kg^(-1)),followed by the lower Cd level(control).The combined application of bio-stimulants and EDTA minimized the negative impacts of Cd *** highest increase in seedling emergence(5.44%),leaf area(50.60%),number of tillers(31.02%),grain yield per plant(24.28%),biological yield(13.97%),and decrease in Cd levels in grains(40%)was noticed where 20%foliar application of *** and 10%of *** biostimulants were done using 5 mg kg^(-1) of soil-applied *** intervention demonstrated a notable reduction in Cd-induced negative effects,highlighting the potential of these substances in promoting sustainable wheat cultivation in contaminated ***,it is an eco-friendly and approachable method at theﬁeld level able to ensure food safety.

关键词： Abiotic stress allometric characters antioxidant activity crop yield seed emergence grain yield

Effects of the kinetic pattern of dietary glucose release on nitrogen utilization, the portal amino acid profile, and nutrient transporter expression in intestinal enterocytes in piglets

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Journal of Animal Science and Biotechnology 2024年第05期 2106-2121页

作者： Zexi Li Yunfei Li Yufei Zhao Guifu Wang Rujie Liu Yue Li qamar Aftab Zewei Sun Qingzhen Zhong Jilin Province Key Laboratory of Animal Nutrition and Feed Science College of Animal Science and Technology Key Lab of Animal Production Product Quality and Security Ministry of Education Jilin Agricultural University Dongfeng County Sika Deer Industry Development Service Center

Background Promoting the synchronization of glucose and amino acid release in the digestive tract of pigs could effectively improve dietary nitrogen utilization. The rational allocation of dietary starch sources and the exploration of appropriate dietary glucose release kinetics may promote the dynamic balance of dietary glucose and amino acid supplies. However, research on the effects of diets with different glucose release kinetic profiles on amino acid absorption and portal amino acid appearance in piglets is limited. This study aimed to investigate the effects of the kinetic pattern of dietary glucose release on nitrogen utilization, the portal amino acid profile, and nutrient transporter expression in intestinal enterocytes in *** Sixty-four barrows(15.00 ± 1.12 kg) were randomly allotted to 4 groups and fed diets formulated with starch from corn, corn/barley, corn/sorghum, or corn/cassava combinations(diets were coded A, B, C, or D respectively). Protein retention, the concentrations of portal amino acid and glucose, and the relative expression of amino acid and glucose transporter m RNAs were investigated. In vitro digestion was used to compare the dietary glucose release *** Four piglet diets with different glucose release kinetics were constructed by adjusting starch sources. The in vivo appearance dynamics of portal glucose were consistent with those of in vitro dietary glucose release kinetics. Total nitrogen excretion was reduced in the piglets in group B, while apparent nitrogen digestibility and nitrogen retention increased(P < 0.05). Regardless of the time(2 h or 4 h after morning feeding), the portal total free amino acids content and contents of some individual amino acids(Thr, Glu, Gly, Ala, and Ile) of the piglets in group B were significantly higher than those in groups A, C, and D(P < 0.05). Cluster analysis showed that different glucose release kinetic patterns resulted in different portal amino acid patterns in piglets

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Prevalence of Malnutrition among Hospitalized Pediatric Patients in a Tertiary Hospital in Jordan: Pilot Study

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Journal of Biosciences and Medicines 2024年第8期12卷 218-229页

作者： Shahdan Al-Dabbas qamar Batayneh Raghad Al-Jawhary Mohammad Hadi Alzoubi Eyad Altamimi Pediatric Department Faculty of Medicine Jordan University of Science and Technology Irbid Jordan Faculty of Medicine Jordan University of Science and Technology Irbid Jordan

Introduction: Failure to thrive (FTT) occurs when a child’s growth falls below expected standards, typically due to inadequate nutrient intake. Factors include insufficient oral intake, poor nutrient absorption, and increased metabolic demands. Previous studies have shown high malnutrition rates in hospitalized children due to illness-related metabolic demands, decreased appetite, and inadequate intake. Our objective was to assess the growth and nutritional status of children admitted to King Abdullah University Hospital (KAUH) and identify the prevalence of undernutrition and associated factors. Methods: This prospective, cross-sectional cohort study was conducted at KAUH from July to December 2022. We included children aged 2 months to 16 years, excluding those with conditions altering growth parameters. Data were collected through pediatric data sheets, physical examinations, and laboratory tests. Anthropometric measurements were taken, and growth was assessed using CDC growth charts. Nutritional anemia was defined as hemoglobin 16. Results: A total of 111 patients were included (56.8% male, median age 65 months). Most patients had normal height (82%) and weight (86.5%) upon admission. However, 14.4% were stunted, 11.7% were underweight, 14.4% were overweight, and 3.6% were obese. Growth impairment correlated with higher anemia rates (p = 0.042). Nutritional anemia was present in 12% of patients. No significant relation was found between breastfeeding history and growth retardation, but maternal perception of malnutrition correlated well with actual malnutrition. Conclusion: Our study found a malnutrition prevalence of 19.8%, highlighting the need for systematic nutritional screening in hospitalized children. The study’s limitations include its small sample size and specific patient population, suggesting the need for larger, multicenter studies for more generalizable results.

关键词： Children Growth Stunting Underweight Malnutrition Nutrition Anemia

ABMRF:An Ensemble Model for Author Profiling Based on Stylistic Features Using Roman Urdu

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Intelligent Automation & Soft Computing 2024年第2期39卷 301-317页

作者： Aiman Muhammad Arshad Bilal Khan Khalil Khan Ali Mustafa qamar Rehan Ullah Khan Department of Computer Science City University of Science and Information TechnologyPeshawarPakistan Department of Computer Science School of Engineering and Digital SciencesNazarbayev UniversityAstanaKazakhstan Department of Computer Science College of ComputerQassim UniversityBuraydahSaudi Arabia Department of Information Technology College of ComputerQassim UniversityBuraydahSaudi Arabia

This study explores the area of Author Profiling(AP)and its importance in several industries,including forensics,security,marketing,and education.A key component of AP is the extraction of useful information from text,with an emphasis on the writers’ages and *** improve the accuracy of AP tasks,the study develops an ensemble model dubbed ABMRF that combines AdaBoostM1(ABM1)and Random Forest(RF).The work uses an extensive technique that involves textmessage dataset pretreatment,model training,and *** evaluate the effectiveness of several machine learning(ML)algorithms in classifying age and gender,including Composite Hypercube on Random Projection(CHIRP),Decision Trees(J48),Na飗e Bayes(NB),K Nearest Neighbor,AdaboostM1,NB-Updatable,RF,andABMRF,they are *** findings demonstrate thatABMRFregularly beats the competition,with a gender classification accuracy of 71.14%and an age classification accuracy of 54.29%,*** metrics like precision,recall,F-measure,Matthews Correlation Coefficient(MCC),and accuracy support ABMRF’s outstanding performance in age and gender profiling *** study demonstrates the usefulness of ABMRF as an ensemble model for author profiling and highlights its possible uses in marketing,law enforcement,and *** results emphasize the effectiveness of ensemble approaches in enhancing author profiling task accuracy,particularly when it comes to age and gender identification.

关键词： Machine learning author profiling AdaBoostM1 random forest ensemble learning text classification

The space time CE/SE method for solving one-dimensional batch crystallization model with fines dissolution

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Chinese Journal of Chemical Engineering 2015年第2期23卷 337-341页

作者： Saima Noor Shamsul qamar Department of Mathematics COMSATS Institute of Information Technology

This article is concerned with the numerical investigation of one-dimensional population balance models for batch crystallization process with fines *** batch crystallization,dissolution of smaller unwanted nuclei below some critical size is of vital importance as it improves the quality of *** crystal growth rates for both size-independent and size-dependent cases are considered.A delay in recycle pipe is also included in the *** space–time conservation element and solution element method,originally derived for non-reacting flows,is used to solve the *** scheme has already been applied to a range of PDEs,mainly in the area of fluid *** numerical results are compared with those obtained from the Koren scheme,showing that the proposed scheme is more efficient.

关键词： Population balances Batch process Crystallization Dissolution of fines Space–time conservation element and solution element method