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EXPERIMENTAL STUDY AND MODELING OF PRESSURE LOSS FOR FOAM-CUTTINGS MIXTURE FLOW IN HORIZONTAL PIPE

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Journal of Hydrodynamics 2011年第4期23卷 431-438页

作者： amna Gumati HIROSHI Takahshi Graduate School of Environmental Studies Tohoku University

In this study, we first sought to elucidate foam rheology to describe foam flow behavior, and then to experimentally investigate the pressure losses for both foam and foam-cuttings flow in a horizontal pipe by considering both varied foam qualities of 80%, 85% and 90% and foam velocities. Also, a two-layer numerical model to predict pressure loss was developed based on experimental observations of cuttings behavior. Results show that the foam behaves like a power-law fluid. Furthermore, and the pressure loss significantly increases as foam velocity increases, while the delivered cuttings concentration dramatically decreases. Moreover, results indicate that both the pressure loss and the delivered cuttings concentration increase with foam quality. Comparisons between the experimental results and numerical model predictions show satisfactory agreement.

关键词： foam rheology pressure loss horizontal pipe cuttings concentration two-layer model

Electron Temperature Measurement Using PIN Diodes as Detectors to Record the X-ray Pulses from a Low-Energy Mather-Type Plasma Focus

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Plasma Science and Technology 2004年第2期6卷 2199-2203页

作者： M.Asif amna Ikram Institute of Plasma Physics Chinese Academy of SciencesUniversity of Engineering and Technology Lahore 54000 Pakistan Hefei 230031 China Department of Physics Government College University Lahore 54000 Pakistan

In the experiment to determine the plasma electron temperature, a modifiedmultichannel PIN diodes assembly is used as detectors to record the X-ray pulses from a low-energyMather-type plasma focus device energized by a 32μF, 15 kV (3.6kJ) single capacitor, with deuteriumas a filling gas. The ratio of the integrated bremsstrahlung emission transmitting through foils tothe total incident flux as a function of foil thickness at various temperatures is obtained forfoil absorbers of material. Using 3 μm, 6 μm, 9 μm,12 μm,15 μm and 18 μm thick aluminiumabsorbers, the transmitted X-ray flux is detected. By comparing the experimental and theoreticalcurves through a computer program, the plasma electron temperature is determined. Results show thatthe deuterium focus plasma electron temperature is about 800 eV.

关键词： plasma focus PIN diodes X-ray foil absorber thickness

Modeling of All-Optical Even and Odd Parity Generator Circuits Using Metal-Insulator-Metal Plasmonic Waveguides

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Photonic Sensors 2017年第2期7卷 182-192页

作者： Lokendra SINGH amna BEDI Santosh KUMAR Photonics Lab Department of Electronics and Communication Engineering DIT University Dehradun-248009 India

Plasmonic metal-insulator-metal （MIM） waveguides sustain excellent property of confining the surface plasmons up to a deep subwavelength scale. In this paper, linear and S-shaped MIM waveguides are cascaded together to design the model of Mach-Zehnder interferometer （MZI）. Nonlinear material has been used for switching of light across its output ports. The structures of even and odd parity generators are projected by cascading the MZIs. Parity generator and checker circuit are used for error correction and detection in an optical communication system. Study and analysis of proposed designs are carried out by using the MATLAB simulation and finite-difference- time-domain （FDTD） method.

关键词： Plasmonics MIM waveguides Mach-Zehnder interferometer nonlinear process FDTD method

Phytochemical investigation of medicinally important plants of the Pothohar region of Pakistan

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Journal of Traditional Chinese Medicine 2020年第5期40卷 883-890页

作者： amna Rabab Sobia Kanwal Tariq Mahmood Department of Plant Sciences Quaid-i-Azam UniversityIslamabad 45320Pakistan Department of Zoology University of GujratSub-Campus Rawalpindi 46000Pakistan

OBJECTIVE:To report the phytochemical composition(flavonoids,phenolics,saponins,tannins,and terpenoids)and biological activities(antioxidant,phytotoxic,cytotoxic,antifungal activities)of medicinally important plants of Pothohar ***:In the current study various qualitative and quantitative phytochemical tests were conducted to investigate the phytochemical composition of plant extracts prepared in benzene,chloroform and *** same extracts were further utilized in different biological activities i.e.,antioxidant[total antioxidant capacity,total reducing power,and 2,2-diphenyl-1-picrylhydrazyl(DPPH)scavenging assay],phytotoxicity(Radish seed bioassay),brine shrimp cytotoxicity and antifungal activities(against four pathogenic fungal strains).RESULTS:Phytochemical analysis indicate flavonoids,phenolics,saponins,tannins and terpenoids were present in almost all plants however,maximum amount of total phenolic and flavonoid contents was reported in of Malva parviflora and Lepidium *** of Malva parviflora and Lepidium pinnatifidum also depicted the superlative antioxidant activity(total antioxidant capacity,total reducing power,and DPPH scavenging activity).Maximum fungal growth inhibition was demonstrated by extracts of Centaurea calcitropa,Vicia sativa and Malva *** maximum cytotoxicity was shown by the extracts of Centaurea ***,for phytotoxicity assay the highest allelopathic potential was exhibited by extracts of Lepidium *** prejudiced results;the best results were obtained by Methanol followed by Chloroform and ***:Centaurea calcitropa,Vicia sativa,Malva parviflora and Lepidium pinnatifidum are most promising medicinal plants of Pothohar region for future studies.

关键词： Centaurea Malva Cytotoxins Antifungal agents Phytotoxicity Pothohar region

Assessment of phytotoxic, genotoxic and enzyme inhibition potential of Sterculia diversifolia

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Journal of Traditional Chinese Medicine 2022年第4期42卷 595-603页

作者： Fazle Rabbi Amir Zada amna Nisar Department of Pharmacy University of PeshawarPeshawar 25120Khyber PakhtunkhwaPakistan Department of Pharmacy Abasyn University PeshawarPeshawar25000Khyber PakhtunkhwaPakistan.fazle.rabbi@abasyn.edu.pk Telephone:+92-0314-9244566

OBJECTIVE:To evaluate Sterculia diversifolia stem bark and leaves for phytotoxic,genotoxic and enzymes inhibition ***:Phytotoxic activity of both stem bark and leaves were screened using Lemna *** genotoxic activity of Sterculia diversifolia stem bark and leaves extracts were tested using comet assay protocol while enzyme inhibition activity of crude extract and various fractions of both stem bark and leaves were evaluated using acetyl cholinesterase,lipoxygenase,β-glucuronidase,urease,xanthine oxidase and carbonic ***:Phytotoxic activity showed significant results in dose dependant manner in both stem bark(ethyl acetate and n-butanol)and leaves(ethyl acetate,nbutanol and n-hexane)*** genotoxic activity,dichloromethane fraction showed significant activity followed by ethyl acetate *** cholinesterease inhibitory activity showed significant results in both stem bark and leaves fractions,while significant lipoxygenase inhibition was shown by ethyl acetate,dichloromethane,crude extract and n-hexane fractions of both stem bark and leaves.β-glucuronidase,urease and carbonic anhydrase inhibitory activity showed highly significant results in ethyl acetate fraction of both stem bark and leaves,while xanthine oxidase inhibition was shown by dichloromethane fraction of stem bark and leaves ***:This study emphasizes the important phytotoxic,genotoxic and enzyme inhibition effects of Sterculia diversifolia stem bark and ***,it is clear that Sterculia diversifolia stem bark and leaves possess phytotoxic,genotoxic and enzyme inhibitory agents.

关键词： Sterculia plant extracts phytotoxic mutagenicity tests enzymes

Survey on Video Security:Examining Threats,Challenges,and Future Trends

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Computers, Materials & Continua 2024年第9期80卷 3591-3635页

作者： Ali Asghar amna Shifa Mamoona Naveed Asghar Department of Artificial Intelligence Faculty of ComputingThe Islamia University of BahawalpurBahawalpur63100Pakistan School of Computer Science College of Science and EngineeringUniversity of GalwayGalwayH91 TK33Ireland

Videos represent the most prevailing form of digital media for communication,information dissemination,and ***,theirwidespread use has increased the risks of unauthorised access andmanipulation,posing significant *** response,various protection approaches have been developed to secure,authenticate,and ensure the integrity of digital *** study provides a comprehensive survey of the challenges associated with maintaining the confidentiality,integrity,and availability of video content,and examining how it can be *** then investigates current developments in the field of video security by exploring two critical research ***,it examine the techniques used by adversaries to compromise video data and evaluate their *** these attack methodologies is crucial for developing effective defense ***,it explores the various security approaches that can be employed to protect video data,enhancing its transparency,integrity,and *** compares the effectiveness of these approaches across different use cases,including surveillance,video on demand(VoD),and medical videos related to disease ***,it identifies potential research opportunities to enhance video data protection in response to the evolving threat *** this investigation,this study aims to contribute to the ongoing efforts in securing video data,providing insights that are vital for researchers,practitioners,and policymakers dedicated to enhancing the safety and reliability of video content in our digital world.

关键词： Attacks threats security services video manipulation video security

Rising incidence of acute hepatitis A among adults and clinical characteristics in a tertiary care center of Pakistan

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World Journal of Virology 2025年第1期14卷 73-82页

作者： Yumna Shahid amna Subhan Butt Iqra Jamali Faisal Wasim Ismail Division of Gastroenterology Department of MedicineAga Khan University HospitalKarachi 74800Pakistan Department of Medicine Aga Khan University HospitalKarachi 74800Pakistan

BACKGROUND For decades,hepatitis A virus(HAV)has been a leading cause of acute hepatitis among children and was less prevalent among ***,recently a paradigm shift has been observed in the epidemiology of HAV,as evident by cases of acute hepatitis due to HAV among *** To estimate frequency of HAV in acute viral hepatitis and compare characteristics in HAV and hepatitis E virus(HEV)*** This was a trend analysis conducted at Aga Khan University Hospital Karachi(Sindh,Pakistan)from February 2024 to May *** aged 18 years and older diagnosed with acute viral hepatitis attributed to hepatotropic viruses in 2024 were *** compare the trend patients admitted with acute hepatitis during 2019-2023 were also *** regarding clinical and laboratory parameters were *** yearly trend of acute hepatitis due to HAV and HEV was analyzed,and comparative analysis was done between HAV and HEV cases among *** A total of 396 patients were found to have acute hepatitis during our study *** was diagnosed in 234 patients(59%)while 157 patients(39.6%)were found to have acute HEV ***,acute hepatitis B virus infection was identified in 3 patients(0.7%),whereas acute hepatitis C virus infection was found in 2(0.5%)cases of acute *** trends showed increasing occurrence of HAV infection among adults over last 5 *** patients with acute HAV were younger than patients with HEV(28 years±8 years vs 30 years±8 years;P<0.01).Higher levels of total bilirubin were seen in HEV infection,while higher levels of alanine transaminase were seen in HAV ***,a higher proportion of acute liver failure(ALF),coagulopathy,and mortality were observed in *** An increase in acute hepatitis A cases among adults shows less severity than hepatitis E,highlighting the need for better sanitation,hygiene,and adult hepatitis A vaccination programs.

关键词： Acute hepatitis Hepatitis A virus Hepatitis E virus Acute liver failure Hepatotropic virus Vaccination

Integral Transform Method for a Porous Slider with Magnetic Field and Velocity Slip

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Computer Modeling in Engineering & Sciences 2020年第3期122卷 1099-1118页

作者： Naeem Faraz Yasir Khan amna Anjum Anwar Hussain International Cultural Exchange School(ICES) Donghua UniversityShanghaiChina. Department of Mathematics University of Hafr Al-BatinHafar Al-BatinSaudi Arabia. DBS&HCEME National University of Science and TechnologyIslamabadPakistan.

Current research is about the injection of a viscous fluid in the presence of a transverse uniform magnetic field to reduce the sliding *** is a slip-on both the slider and the ground in the two cases,for example,a long porous slider and a circular porous *** utilizing similarity transformation Navier-Stokes equations are converted into coupled equations which are tackled by Integral Transform *** are obtained for different values of Reynolds numbers,velocity slip,and magnetic *** found that surface slip and Reynolds number has a substantial influence on the lift and drag of long and circular sliders,whereas the magnetic effect is also noticeable.

关键词： Porous slider MHD flow Reynolds number velocity slip integral transform method.

A one-step implicit iterative method for two finite families of asymptotically nonexpansive mappings in a hyperbolic space

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Applied Mathematics(A Journal of Chinese Universities) 2018年第3期33卷 274-286页

作者： Hafiz Fukhar-ud-din amna Kalsoom Safeer H Khan Department of Mathematics and Statistics King Fahd University of Petroleum and Minerals Department of Mathematics and Statistics International Islamic University Department of Mathematics Statistics and Physics Qatar University

We introduce a one-step implicit iterative method for two finite families of asymptotically nonexpansive mappings in a hyperbolic space and use it to approximate common fixed points of these families. The results presented in this paper are new in the setting of hyperbolic spaces. On top, these are generalizations of several results in literature from Banach spaces to hyperbolic spaces. At the end of the paper, we give an example to validate our results.

关键词： uniformly convex hyperbolic space asymptotically nonexpansive mapping common fixed point strong convergence