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Effects of grain's shape-and size-polydispersities,orientation,and area fraction on tortuosity and permeability of 2D granular media

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Particuology 2024年第7期90卷 535-557页

作者： Ke Cao Huisu Chen mohammad iqbal Khan Mingqi Li Lin Liu Jiangsu Key Laboratory of Construction Materials School of Materials Science and EngineeringSoutheast UniversityNanjing 211189China Department of Civil Engineering College of EngineeringKing Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China College of Civil and Transportation Engineering Hohai UniversityNanjing210098China

The microstructure of granular media, including grain's shape- and size-polydispersities, orientation, and area fraction can potentially affect its permeability. However, few studies consider the coupling effects of these features. This work employs geometrical probability and stereology to establish quantitative relationships between the above microstructural features and the geometric tortuosity of the two-dimensional granular media containing superellipse, superoval, and polygon grains. Then the lattice Boltzmann method (LBM) is used to determine the permeabilities of these granular media. By combining the tortuosity model and the LBM-derived permeabilities, modified K–C equations are formulated to predict the permeability and the shape factor, considering the grain's shape- and size-polydispersities, orientation, and area fraction. The reliability of these methods can be verified by comparing them with both our simulations and available experimental, theoretical, and numerical data reported in the literature. The findings implicate that the tortuosity and permeability of the granular media are strongly correlated with the grain's shape, orientation, and area fraction but unaffected by the size polydispersity and spatial arrangement of grains. Only circularity is not enough to derive a unified formula for considering the impact of grain shape on tortuosity and permeability, other shape parameters need to be explored in the future.

关键词： Geometric tortuosity Konzey-Carman equation Shape and size ploydispersities Grain orientation Lattice Boltzmann method Granular media

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Liquid injectivity in a SAG foam process:Effect of permeability

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Petroleum Science 2024年第1期21卷 302-314页

作者： Jia-Kun Gong Yuan Wang Ridhwan-Zhafri B.Kamarul Bahrim Raj-Deo Tewari mohammad-iqbal Mahamad Amir Rouhi Farajzadeh William Rossen College of Mechanics and Materials Hohai UniversityNanjing210098JiangsuChina College of Water Conservancy&Hydropower Engineering Hohai UniversityNanjing210098JiangsuChina PETRONAS Kuala Lumpur50088Malaysia Department of Geoscience and Engineering Delft University of Technology2628 CNDelftthe Netherlands Shell Global Solutions International B.V. 1031 HWAmsterdamthe Netherlands

Foam is utilized in enhanced oil recovery and CO_(2) ***-alternating-gas(SAG)is a preferred approach for placing foam into reservoirs,due to it enhances gas injection and minimizes corrosion in *** previous studies with similar permeability cores show that during SAG injection,several banks occupy the area near the well where fluid exhibits distinct ***,underground reservoirs are heterogeneous,often *** is crucial to understand the effect of permeability on fluid behaviour and injectivity in a SAG *** this work,coreflood experiments are conducted in cores with permeabilities ranging from 16 to 2300 *** observe the same sequence of banks in cores with different ***,the speed at which banks propagate and their overall mobility can vary depending on *** higher permeabilities,the gas-dissolution bank and the forced-imbibition bank progress more rapidly during liquid *** total mobilities of both banks decrease with *** utilizing a bank-propagation model,we scale up our experimental findings and compare them to results obtained using the Peaceman *** findings reveal that the liquid injectivity in a SAG foam process is misestimated by conventional simulators based on the Peaceman *** lower the formation permeability,the greater the error.

关键词： Foam Enhanced oil recovery Surfactant-alternating-gas Injectivity Permeability

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Spatial modeling of solar photovoltaic power plant in Kabul,Afghanistan

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Journal of Mountain Science 2021年第12期18卷 3291-3305页

作者： NASERI mohammad HUSSAINI mohammad Salem iqbal mohammad Wasim JAWADI Hussain Ali PUYA Marzia Afghanistan National Water and Environmental Research Center(ANWERC) Kabul 1006Afghanistan Department of Geology Faculty of GeosciencesBamyan UniversityBamyan 1601Afghanistan School of Sustainable Engineering and the Built Environment Arizona State UniversityTempe AZ 85287-3005USA Department of Engineering Geology and Hydrogeology Kabul Polytechnic UniversityKabul 1006Afghanistan

Energy planning and solar plant site selections are vital strategic decisions and one of the most complex executive challenges in the interconnected *** is essential to study the potential renewable energy sources in Afghanistan to select the most sustainable sites for solar power production in populated *** study is based on the combination of a Geographic Information System,Remote sensing,and multi-criteria decision-making technique to evaluate the optimal placement of photovoltaic solar power plants in the Kabul province,capital of *** models,Analytical Hierarchy Process(AHP)and Analytical Network Process(ANP),were used to select suitable areas for establishing a solar power *** application of the proposed model has been made possible by integrating four constraints such as climate,environmental,topography,and economical which comprised twelve criteria:solar radiation,yearly average rainfall,land slope,aspect,land use,dust,geology and proximity to faults,main roads,Normalized difference vegetation index,urban areas river and water *** findings indicate that there is no considerable difference between the results of both models since both models identified more than 20%of the total area of Kabul province in suitable *** maps conclude that northern and southern parts of Kabul city and the eastern part of Kabul province came to the range of suitable *** can be concluded that Kabul province is a source of sufficient potential for producing solar *** results of this study can support the plans of the Afghanistan government in solar energy production and the implementation of photovoltaic power plants.

关键词： Photovoltaic Spatial modeling AHP ANP Kabul GIS

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Evaporative/radiative electrospun membrane for personal cooling

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Nano Research 2023年第2期16卷 2563-2571页

作者： mohammad Irfan iqbal Shuo Shi Gokula Manikandan Senthil Kumar Jinlian Hu Institute of Textiles and Clothing The Hong Kong Polytechnic UniversityHong Kong 999077China Department of Biomedical Engineering City University of Hong KongHong Kong 999077China Department of Building Environment and Energy Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China

Functional textiles that promote daily comfort and productivity must efficiently release body sweats and transmit radiative heat through sweat evaporation and mid-infrared radiation(MIR)(8–13μm).However,most of the traditional clothing cannot provide simultaneous sweat evaporation and mid-infrared radiation transmission efficiently,leading to a poor design of personal cooling ***,an evaporative/radiative integrated functional fibrous electrospun membrane is meticulously designed and controllably fabricated via facile electrospinning technology for personal cooling *** developed membrane can be applied as a smart wearable with distinct personal thermal management *** promising temperature and humidity responsive vapor transmission of the membrane grants 1.2 times of evaporative cooling than that of traditional ***,based on its high mid-infrared radiation transmission(53%)property in the range of 8–13μm,the as-spun membrane provides extra cooling of 1.5°C than that of ***,the building energy saving performances demonstrated that 47.1%annual building cooling can be achieved using the developed electrospun *** general,the evaporative/radiative electrospun membrane creates a passive cooling microclimate for the human body,meeting the growing demand of wearable for personal cooling.

关键词： building energy cooling management electrospinning evaporative cooling radiative cooling

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Nitrate contamination in groundwater of Kabul Province,Afghanistan:Reasons behind and conceptual management framework discourse

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Journal of Mountain Science 2022年第5期19卷 1274-1291页

作者： JAWADI Hussain Ali iqbal mohammad Wasim NASERI mohammad FARAHMAND Asadullah AZIZI Abdul Haseeb EQRAR mohammad Naiem Afghanistan National Water and Environmental Research Center(ANWERC) Kabul 1006Afghanistan Department of Geology Faculty of GeosciencesBamyan UniversityBamyan CityBamyan 1601Afghanistan School of Sustainable Engineering and the Built Environment Arizona State UniversityTempe AZ 85287-8704USA Department of Hydrogeology Ministry of Energy and WaterKabul 1006Afghanistan CITEngineering International Co. LtdTokyoJapan Department of Geology Faculty of GeosciencesKabul UniversityKabul 1006Afghanistan

Groundwater contamination has been on the rise in *** has become a major concern among the policy *** paper aims to propose practical options for the management of nitrate contamination in one of Afghanistan’s groundwater polluted provinces,*** management framework utilized Mann-Kendall and Sen Slope tests to detect nitrate trend and geostatistical analysis option in Arc GIS 10.5 to assess the nitrate *** explore the impact of various management options,a number of legislative documents were *** results indicate a decline in the nitrate storage of Kabul aquifers from 108 mg/L in 2005 to 0.044 mg/L in *** the whole period of the study,the results show that the nitrate volumes remain lower than the nitrate concentration range proposed by World Health Organization(50 mg/L).Groundwater dynamics in Kabul aquifers were influenced by nitrate derived from precipitation and nitrate input from root zones in agricultural ***,different management options for groundwater pollution from nitrate and corresponding authorities,incorporated urban,rural and agriculture,were *** is expected that this study will help policy makers to better manage the nitrate storage of Kabul aquifers by implementing the proposed management options.

关键词： Nitrate concentration Groundwater Afghanistan Effective parameter Management option

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Royal Crown Shaped Polarization Insensitive Perfect Metamaterial Absorber for C-, X-, and Ku-Band Applications

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Computers, Materials & Continua 2023年第7期76卷 455-469页

作者： Md.Salah Uddin Afsar mohammad Rashed iqbal Faruque Sabirin Abdullah mohammad Tariqul Islam Space Science Centre(ANGKASA) Institute of Climate Change(IPI)Universiti Kebangsaan MalaysiaUKMBangi43600Selangor D.E.Malaysia Department of Electrical Electronic&Systems EngineeringFaculty of Engineering&Built EnvironmentUniversiti Kebangsaan MalaysiaUKMBangi43600Selangor D.E.Malaysia

This study proposed a new royal crown-shaped polarisation insensitive double negative triple band microwave range electromagnetic metamaterial absorber(MA).The primary purpose of this study is to utilise the exotic characteristics of this perfect metamaterial absorber(PMA)for microwave wireless *** fundamental unit cell of the proposed MA consists of two pentagonal-shaped resonators and two inverse C-shaped metallic components surrounded by a split ring resonator(SRR).The bottom thin copper deposit and upper metallic resonator surface are disjoined by an FR-4 dielectric substrate with 1.6 mm *** CST MW studio,a high-frequency electromagnetic simulator has been deployed for numerical simula-tion of the unit cell in the frequency range of 4 to 14 *** the TE mode,the offered MA structure demonstrated three different absorption peaks at 6.85 GHz(C-band),8.87 GHz(X-band),and 12.03 GHz(Ku-band),with 96.82%,99.24%,and 99.43%absorptivity,*** electric field,magnetic field,and surface current distribution were analysed using Maxwell’s-Curl equations,whereas the angle sensitivity was investigated to comprehend the absorption mechanism of the proposed *** numerical results were verified using the Ansys HFSS(high-frequency structure simulator)and ADS(advanced design system)for equivalent circuit ***,the proposed MA is polarisation and incident angle ***,the application of this MA can be extended to a great extent,including airborne radar applications,defence,and stealth-coating technology.

关键词： Absorptivity DNG wide angle incidence TEM wide oblique angle

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Farmers' perceptions of and adaptations to drought in Herat Province, Afghanistan

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Journal of Mountain Science 2018年第8期15卷 1741-1756页

作者： mohammad Wasim iqbal Somchai DONJADEE Bancha KWANYUEN LIU Shi-yin Irrigation Technology Research Laboratory Department of Irrigation Engineering Faculty of Engineering at Kamphaeng Saen Kasetsart University Institute of International Rivers and Eco-security Yunnan University

Drought is a significant natural hazard in Herat Province, Afghanistan. The objective of this study was to explore farmers' perceptions of the drought's prevalence and characteristics, its socioeconomic and environmental impacts, their strategies for coping with and mitigating it, and types of conflicts and resolution mechanisms. A questionnaire was completed by 147 farming households. The results indicate that farmers' perceptions regarding drought are in line with the results obtained using the precipitation data. Even though the respondents have religious belief in interpreting the weather related issues, they also perceived drought as the climatic and environmental factors such as increased temperature, decreased precipitation, and other factors like war, financial weakness, deforestation, over-exploitation of groundwater, lack of electricity supply etc. The results show that drought has had serious economic impacts, including loss of employment and reduction in crop yield and livestock production, which have reduced farmers' livelihood options and weakened their financial situation. Social impacts have included migration, a sense of hopelessness and loss, conflicts over water, health problems, impacts on the schooling of children, malnutrition, and limits to food options. Significant environmental impacts such as an increase in temperature, pasture and forest degradation, deterioration of water quality, damage to fish and wildlife habitats, and groundwater depletion were also reported. Farmers used local techniques to adapt to drought and lessen its effects. Farmers perceived irrigation water to be a major source of conflict. Local elders, water-user associations, and formal courts were reported to be the most successful conflict resolution methods. It is expected that the results of this study will support policy makers within government and development agencies in Afghanistan to develop future drought adaptation policies.

关键词： Adaptation strategies Perception Agriculture Drought impacts Water conflict

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Non-occupational lead exposure and hypertension in Pakistani adults

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第9期7卷 732-737页

作者： RAHMAN Sohaila KHALID Nasir ZAIDI Jamshed Hussain AHMAD Shujaat iqbal mohammad Zafar Nuclear Chemistry Division Pakistan Institute of Nuclear Science and Technology P. O. Nilore Islamabad 45650 Pakistan Dean Faculty of Biosciences University of Health Sciences Lahore 54590 Pakistan

Hypertension is one of the most prevalent diseases in the developed and developing countries. Based on the long historical association and the provocative findings of blood pressure effects at low level of lead exposure a study was carried out to determine if an association existed between low blood lead concentration and hypertension. In this study the effects of low-level exposure to lead on blood pressure were examined among 244 adults using atomic absorption spectrometer. For quality assurance purpose certified reference materials i.e., Animal blood A-13, Bovine liver 1577 and cotton cellulose V-9 from IAEA （International Atomic Energy Agency） and NIST （National Institute of Standard Technology） were analyzed under identical experimental conditions. The mean age of hypertensive adults was 52 years （range 43-66）. The mean values of systolic and diastolic blood pressure were （209±11.7）（range 170-250） and （117±3.9）（range 105-140） mmHg respectively. Blood lead concentration ranged from 78-201 μg/L with a mean of 139 μg/L and 165-497 μg/L with a mean of 255 μg/k in normal and hypertensive adults respectively. Increase in systolic blood pressure was significantly predictive with increase in blood lead levels. Body mass index （BMI） and lipid profile including total cholesterol, low density lipoprotein cholesterol, high density lipoprotein cholesterol and triglyceride correlated with blood pressure.

关键词： Hypertension Lead exposure Biochemical parameters Body mass index

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Detecting anomalies in blockchain transactions using machine learning classifiers and explainability analysis

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Blockchain(Research and Applications) 2024年第3期5卷 106-122页

作者： mohammad Hasan mohammad Shahriar Rahman Helge Janicke iqbal H.Sarker Department of Computer Science and Engineering Premier University4000 ChitagongBangladesh Department of Computer Science and Engineering United International University1212 DhakaBangladesh Cyber Security Cooperative Research Centre 6027 PerthAustralia Centre for Securing Digital Futures Edith Cowan University6027 PerthAustralia

As the use of blockchain for digital payments continues to rise,it becomes susceptible to various malicious *** detecting anomalies within blockchain transactions is essential for bolstering trust in digital ***,the task of anomaly detection in blockchain transaction data is challenging due to the infrequent occurrence of illicit *** several studies have been conducted in the field,a limitation persists:the lack of explanations for the model’s *** study seeks to overcome this limitation by integrating explainable artificial intelligence(XAI)techniques and anomaly rules into tree-based ensemble classifiers for detecting anomalous Bitcoin *** shapley additive explanation(SHAP)method is employed to measure the contribution of each feature,and it is compatible with ensemble ***,we present rules for interpreting whether a Bitcoin transaction is anomalous or ***,we introduce an under-sampling algorithm named XGBCLUS,designed to balance anomalous and non-anomalous transaction *** algorithm is compared against other commonly used under-sampling and over-sampling ***,the outcomes of various tree-based single classifiers are compared with those of stacking and voting ensemble *** experimental results demonstrate that:(i)XGBCLUS enhances true positive rate(TPR)and receiver operating characteristic-area under curve(ROC-AUC)scores compared to state-of-the-art under-sampling and over-sampling techniques,and(ii)our proposed ensemble classifiers outperform traditional single tree-based machine learning classifiers in terms of accuracy,TPR,and false positive rate(FPR)scores.

关键词： Anomaly detection Blockchain Bitcoin transactions Data imbalance Data sampling Explainable AI Machine learning Decision tree Anomaly rules

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成人胆总管囊肿诊断和治疗

成人胆总管囊肿诊断和治疗

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作者： mohammad iqbal（巴力）山东大学

学位级别：硕士

目的：探讨成人胆总管囊肿的诊断和治疗。方法：收集2004年5月至2009年5月收治于齐鲁医院肝胆外科和单县中心医院的72例成人胆总管囊肿患者临床资料。病人一般情况：2例患者中男20例,女52例,年龄18-67岁(平均31岁)。诊断情况：I型41例,... 详细信息

目的：探讨成人胆总管囊肿的诊断和治疗。方法：收集2004年5月至2009年5月收治于齐鲁医院肝胆外科和单县中心医院的72例成人胆总管囊肿患者临床资料。病人一般情况：2例患者中男20例,女52例,年龄18-67岁(平均31岁)。诊断情况：I型41例,IVa型28例,IVb型3例,无其他类型患者。术前处理：总胆红素水平过高>300μ mol/L的患者行术前行胆总管囊肿穿刺引流术。治疗情况：6例囊肿癌变患者中4例因多发脏器受累未能行手术治疗,余68例患者均行手术治疗。68例手术患者中,1例胆总管胰腺段癌变患者行胰十二指肠切除术,1例合并左肝内胆管癌变患者行胆总管囊肿切除+左半肝切除术,余66例行胆总管囊肿切除+肝管空肠Roux-en-Y吻合术,其中17例联合肝部分切除术。统计患者近期(如胰腺炎、胰瘘、胆瘘等)及远期(主要是胆总管囊肿癌变)并发症率。结果：4例未手术患者均于确诊后2年内死亡,手术的68例患者中,术后出现胰腺炎2例,胆瘘3例,胰瘘1例经保持通畅引流及积极保守治疗后治愈出院遥随访1～8年。癌变患者中1例行胰十二指肠切除的癌变患者术后出现胰漏,经保守治疗好转出院,术后生存3年。最后1例胆总管囊肿切除+左半肝切除的癌变患者术后生存4年。5例术后反复出现轻度反流性胆管炎袁给予对症保守治疗后症状逐渐缓解,3例术后合口狭窄其中1例合并肝内胆管结石,3例均再次行手术治疗术后症状消失。总之,术后出现近期并发症患者6例(9%),随访1-8年,4例癌变未手术患者均于确诊后2年内死亡,出现远期并发症(主要是胆囊管癌变)患者8例(12%)。结论：成人胆总管囊肿患者明确诊断后,应尽早手术,将囊肿完整切除术,达到改善患者生活质量、延攻患者生存时间的目的,手术方式以胆总管囊肿切除+肝管空肠Roux-en-Y(?)吻合为首选术式。

关键词：成人胆总管囊肿诊断治疗

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