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Numerical Study of Unsteady MhD Flow and Entropy Generation in a Rotating Permeable Channel with Slip and hall Effects

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Communications in Theoretical Physics 2018年第11期69卷 641-650页

作者： Z.h.Khan O.D.Makinde R.ahmad W.A.Khan State Key Laboratory of hydraulics and Mountain River Engineering College of Water Resource & HydropowerSichuan University Key Laboratory of Advanced Reactor Engineering and Safety Ministry of Education Tsinghua University Faculty of Military Science Stellenbosch University School of Mathematics and Physics University of Queensland Faculty of Engineering Sciences GIK Institute of Engineering Sciences and Technology Department of Mechanical Engineering College of Engineering Prince Mohammad Bin Fahd University

This article investigates an unbiased analysis for the unsteady two-dimensional laminar flow of an incompressible, electrically and thermally conducting fluid across the space separated by two infinite rotating permeable *** influence of entropy generation, hall and slip effects are considered within the flow analysis. The problem is modeled based on valid physical arguments and the unsteady system of dimensionless PDEs (partial differential equations) are solved with the help of Finite Difference Scheme. In the presence of pertinent parameters, the precise movement of the flow in terms of velocity, temperature, entropy generation rate, and Bejan numbers are presented graphically, which are parabolic in nature. Streamline profiles are also presented, which exemplify the accurate movement of the flow. The current study is one of the infrequent contributions to the existing literature as previous studies have not attempted to solve the system of high order non-linear PDEs for the unsteady flow with entropy generation and hall effects in a permeable rotating channel. It is expected that the current analysis would provide a platform for solving the system of nonlinear PDEs of the other unexplored models that are associated to the two-dimensional unsteady flow in a rotating channel.

关键词： unsteady flow rotating permeable channel MhD slip hall effects entropy analysis finite difference method

A New Class of L-Moments Based Calibration Variance Estimators

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Computers, Materials & Continua 2021年第3期66卷 3013-3028页

作者： Usman Shahzad Ishfaq ahmad Ibrahim Mufrah Almanjahie Nadia h.Al Noor Muhammad hanif Department of Mathematics and Statistics International Islamic UniversityIslamabad46000Pakistan Department of Mathematics and Statistics PMAS-Arid Agriculture UniversityRawalpindi46300Pakistan Department of Mathematics King Khalid UniversityAbha62529Saudi Arabia Statistical Research and Studies Support Unit King Khalid UniversityAbha62529Saudi Arabia Department of Mathematics College of ScienceMustansiriyah UniversityBaghdad10011Iraq

Variance is one of themost important measures of descriptive statistics and commonly used for statistical *** traditional second-order central moment based variance estimation is a widely utilized ***,traditional variance estimator is highly affected in the presence of extreme *** this paper initially,proposes two classes of calibration estimators based on an adaptation of the estimators recently proposed by Koyuncu and then presents a new class of L-Moments based calibration variance estimators utilizing L-Moments characteristics(L-location,Lscale,L-CV)and auxiliary *** is demonstrated that the proposed L-Moments based calibration variance estimators are more efficient than adapted *** data is considered for assessing the performance of the proposed *** also demonstrated an application related to apple fruit for purposes of the *** artificial and real data sets,percentage relative efficiency(PRE)of the proposed class of estimators with respect to adapted ones are *** PRE results indicate to the superiority of the proposed class over adapted ones in the presence of extreme *** this manner,the proposed class of estimators could be applied over an expansive range of survey sampling whenever auxiliary information is available in the presence of extreme values.

关键词： L-moments variance estimation calibration approach stratified random sampling

Effect of Niobium on Microstructure of Cast AISI h13 hot Work Tool Steel

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Journal of Iron and Steel Research(International) 2008年第4期15卷 61-66页

作者： Shahram Kheirandish ahmad Noorian Department of Material Science and Metallurgical Engineering Iran University of Science and TechnologyTehran 16846-13114 Iran

The effect of niobium addition on the microstructure of cast AISI h13 hot work tool steel was evaluated by using EDX analyzer attached to the scanning electron microscope. The volume percent of eutectic area and eutectic cell size and also volume percent of different carbides of new steel, which is heat treated under different conditions, are also determined. The results show that the a niobium addition modifies the cast structure of Nb-alloyed hot work tool steel, and reduces the size and volume of eutectic cells, and increases the maximum hardness of the steel.

关键词： hot work tool steel h13 niobium NbC microstructure

Control of ovule development in Vitis vinifera by VvMADS28 and interacting genes

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horticulture Research 2023年第6期10卷 43-55页

作者： Songlin Zhang Li Wang Jin Yao Na Wu Bilal ahmad Steve van Nocker Jiuyun Wu Riziwangguli Abudureheman Zhi Li Xiping Wang State Key Laboratory of Crop Stress Biology in Arid Areas College of HorticultureNorthwest A&F UniversityYanglingShaanxi 712100China Key Laboratory of horticultural Plant Biology and Germplasm Innovation in Northwest China Ministry of AgricultureNorthwest A&F UniversityYanglingShaanxi 712100China College of horticulture Hebei Agricultural UniversityBaoding 071000China Agriculture Genomics Institute Chinese Academy of Agricultural SciencesShenzhen 518000China Department of horticulture Michigan State UniversityEast LansingMI 48823USA Turpan Research Institute of Agricultural Sciences Xinjiang Academy of Agricultural SciencesTurpan 838000XinjiangChina

Seedless grapes are increasingly popular throughout the world,and the development of seedless varieties is a major breeding *** this study,we demonstrate an essential role for the grapevine MADS-box gene VvMADS28 in morphogenesis of the *** found that VvMADS28 mRNA accumulated in the ovules of a seeded cultivar,‘Red Globe’,throughout the course of ovule and seed development,especially within the integument/seed *** contrast,in the seedless cultivar‘Thompson Seedless’,VvMADS28 was expressed only weakly in ovules,and this was associated with increased levels of histone h3 lysine 27 trimethylation(h3K27me3)within the VvMADS28 promoter ***-mediated transient suppression of VvMADS28 expression in‘Red Globe’led to reduced seed size associated with inhibition of episperm and endosperm cell *** overexpression of VvMADS28 in transgenic tomatoes interfered with sepal development and resulted in smaller fruit but did not obviously affect seed *** in yeast cells showed that VvMADS28 is subject to regulation by the transcription factor VvERF98,and that VvMADS28 could interact with the Type I/MβMADS-domain protein ***,through DNA-affinity purification-sequencing(DAP-seq),we found that VvMADS28 protein specifically binds to the promoter of the grapevine WUSChEL(VvWUS)gene,suggesting that maintenance of the VvMADS28–VvMADS5 dimer and VvWUS expression homeostasis influences seed *** together,our results provide insight into regulatory mechanisms of ovule and seed development associated with VvMADS28.

关键词： Vitis homeostasis breeding

Influence of absorber doping in a-SiC:h/a-Si:h/a-SiGe:h solar cells

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Journal of Semiconductors 2012年第4期33卷 1-6页

作者： Muhammad Nawaz Ashfaq ahmad University Graduate Centre(UNIK) Gunnar Randers Vei 19P.O.Box 70N-2027 KjellerNorway COMSATs Institute of Information Technology Off-Raiwand RoadLahore-54000Pakistan

This work deals with the design evaluation and influence of absorber doping for aSi：h/aSiC：h/a SiGe：h based thinfilm solar cells using a twodimensional computer aided design （TCAD） tool. Various physical parameters of the layered structure, such as doping and thickness of the absorber layer, have been studied. For reliable device simulation with realistic predictability, the device performance is evaluated by implementing nec essary models （e.g., surface recombinations, thermionic field emission tunneling model for carrier transport at the heterojunction, SchokleyRead hall recombination model, Auger recombination model, bandgap narrowing ef fects, doping and temperature dependent mobility model and using FermiDirac statistics）. A single absorber with a graded design gives an efficiency of 10.1% for 800 nm thick multiband absorption. Similarly, a tandem design shows an efficiency of 10.4% with a total absorber of thickness of 800 nm at a bandgap of 1.75 eV and 1.0 eV for the top aSi and bottom aSiGe component cells. A moderate ndoping in the absorber helps to improve the efficiency while p doping in the absorber degrades efficiency due to a decrease in the Voc （and fill factor） of the device.

关键词： solar cells modeling TCAD amorphous silicon hIT cells

hacking Anti-Shoplifting System to hide Data within Clothes

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Computers, Materials & Continua 2021年第4期67卷 659-674页

作者： Al hussien Seddik Saad E.h.hafez Zubair ahmad Department of Computer Science Faculty of ScienceMinia UniversityAl-Minya61519Egypt Department of Mathematics Faculty of ScienceHelwan UniversityCairoEgypt Department of Statistics Yazd UniversityYazdIran

Steganography has been used to prevent unauthorized access to private information during *** is the scheme of securing sensitive information by concealing it within carriers such as digital images,videos,audio,or *** steganography methods are working by assigning a cover le then embed the payload within it by making some modications,creating the ***,the left traces that are caused by these modications will make steganalysis algorithms easily detect the hidden *** to solve this issue,a novel,highly robust steganography method based on hacking anti-shoplifting systems has proposed to hide data within *** anti-Shoplifting system is an anti-theft security system that protects goods and products,leaving the store in an illegal way(i.e.,without paying for them).The proposed method works by modifying the default anti-shoplifting system by changing its built-in soft RFID(radio-frequency identication)tags sewn in clothes into NFC(Near Field Communication)*** NFC tags are smart tags that can communicate with NFC-Enabled smart-phones using NDEF(NFC Data Exchange Format).NDEF is one of the advancements added to RFID technology by NFC,which allows the data *** NDEF message has one/more NDEF records that contain record type,a unique ID,a length,and a payload of data that contains the secret message content that can be any type of data that ts in a byte *** on NDEF and NFC-enabled smart-phones,the proposed method will take the secret message from the sender,make use of his NFC-enabled smart-phone to communicate with the NFC tag,then hide the secret message within the NDEF’s payload of the NFC tag stuck in ***,to evaluate the proposed method,it has been compared with default(digital)steganography weak *** as time,lockable,robustness,attacks,capacity,and a few more *** results and comparisons showed that the proposed method is more efcient than default(digital)steganography and

关键词： Near-eld communication radio-frequency identication Steganography data hiding tags

A transferred regulator that contributes to Xanthomonas oryzae *** oxidative stress adaptation and virulence by regulating the expression of cytochrome bd oxidase genes

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Journal of Integrative Agriculture 2022年第6期21卷 1673-1682页

作者： WANG Pei-hong WANG Sai NIE Wen-han WU Yan Iftikhar ahmad Ayizekeranmu YIMING hUANG Jin ChEN Gong-you ZhU Bo Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station/Shanghai Cooperative Innovation Center of Agri-Seeds School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240P.R.China Department of Environmental Sciences COMSATS University IslamabadVehari-CampusVehari 61100Pakistan

horizontal gene transfer(hGT)has been well documented as a driving force in the evolution of *** has been shown that a horizontally acquired gene,xoc_2868,involved in the global response against oxidative stress and pathogenicity of Xanthomonas oryzae *** strain ***,as a transcriptional factor(TF),the regulatory mechanism of XOC_2868 has not yet been ***,evolutionary analysis suggested XOC_2868 might be co-transferred with its physically proximate downstream genes from a Burkholderiaceae ***,RNA-seq data of wild-type(BLS256)andΔxoc_2868 strains under oxidative stress showed that XOC_2868 did not regulate the expression of its adjacent genes,but remarkably influenced the expression of several genes involved in the extracellular polysaccharide(EPS)production and xanthan *** immunoprecipitation-sequence(ChIP-seq)combined with transcriptome analysis revealed that XOC_2868 directly regulates a cydAB operon,encoding two subunits of cytochrome bd oxidase and involved in redox *** withΔxoc_2868 strain,cydA-and cydAB-knockout mutants also showed a higher sensitivity to h_(2)O_(2)along with a reduced bacterial virulence compared with the wild-type ***,our findings raise the possibility of regulatory circuit evolution shaped by hGT and driven by selection and reveal a novel regulatory pathway that regulates the expression of cytochrome bd oxidase and thus contributes to the virulence of BLS256.

关键词： hGT transcriptional factor Xanthomonas oryzae pv.oryzicola oxidative stress adaptation and virulence

Dark energy in five-dimensional Brans-Dicke cosmology with dimensional reduction

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Research in Astronomy and Astrophysics 2011年第8期11卷 888-894页

作者： ahmad Rami El-Nabulsi Department of Nuclear Engineering Cheju National University South Korea College of Mathematics and Information Sciences Neijiang Normal University

We explore a 5D Brans-Dicke scalar cosmology by conjecturing that the four-dimensional hubble parameter varies as h = εФ^s, ε ∈ R and s is some unknown power index and that the extra-dimensions compactify as the visible dimensions expand as b（t） ≈ a^x （t）, x ∈R^-. We mainly discuss the case x = - 1. For critical values of e close to unity, it was observed that the acceleration of the universe occurs at red- shift close to z = 0.8 which indicates that in our model, accelerated expansion of the universe began only recently. Several interesting points are revealed and discussed in some detail.

关键词： Brans-Dicke cosmology -- dark energy

hepatoprotective and Antioxidant Activity of Rhizome of Podophyllum hexandrum against Carbon Tetra Chloride Induced hepatotoxicity in Rats

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Biomedical and Environmental Sciences 2013年第3期26卷 209-221页

作者： Showkat ahmad GANIE Bilal ahmad ZARGAR Akbar MASOOD Mohammad Afzal ZARGAR Department of Biochemistry University of Kashmir Department of Pharmaceutical Sciences University of Kashmir

Objective To test possible antioxidant activity of n-hexane extract of Podophyllum hexandrum under in vitro and in vivo conditions. Methods The in vitro antioxidant activity was evaluated by the ability of the extract to interact with the stable free radical DPPh, Superoxide （02）, hydroxyl （Oh）, hydrogen peroxide （h202） radicals, and reducing power ability of the extract was also evaluated. Under in vivo conditions the extract was evaluated for its hepatoprotective activity by measuring different biochemical parameters, such as serum alanine aminotransaminase, serum aspartate aminotransaminase and serum lactate dehydrogenase and antioxidant enzymes. Antioxidant status was estimated by determining the activities of antioxidative enzymes, glutathione reductase （GR）, glutathione peroxidase （GPx）, glutathione-S-transferase （GST） and superoxide dismutase （SOD）, and by determining the levels of reduced glutathione （GSh） and thiobarbituric acid reactive substances （TBARS）. Results hexane extract of P. hexondrum exhibited good radical scavenging capacity in neutralization of DPPh, O2-, Oh, and h202 radicals in a dose dependent manner, n-hexane extract of Podophyllum hexandrum at the doses of 20, 30, and 50 mg/kg-day produced hepatoprotective effect by decreasing the activity of serum marker enzymes, while it significantly increased the levels of glutathione （GSh）, glutathione peroxidase （GPx）, glutathione reductase （GR）, super oxide dismutase （SOD）, and glutathione-S-transferase （GST） in a dose dependant manner. The effect of n-hexane extract was comparable to that of standard antioxidant vitamin E. Conclusion The extract of Podophyllum hexandrum possess free radical scavenging activity under in vitro conditions and could protect the liver tissue against CCI4 induced oxidative stress probably by increasing antioxidant defense activities.

关键词： Podophyllum hexandrum Free radicals in-vitro experiments Biochemical parameters Antioxidant Liver protection