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Aconitum heterophyllum *** Royle:A critically endangered medicinal herb with rich potential for use in medicine

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Journal of Integrative Medicine 2022年第2期20卷 104-113页

作者： Tareq A.Wani Zahoor A.kaloo Nisar A.Dangroo Plant Tissue Culture Laboratory Department of BotanyUniversity of KashmirSrinagarJammu and Kashmir 190006India Department of Chemistry National Institute of TechnologySrinagarJammu and Kashmir 190006India

Aconitum heterophyllum(Patrees)is a critically endangered medicinal herb of the northwestern Himalayas and has enormous pharmacological *** is the only nonpoisonous member of the genus Aconitum,and has been used as a medicinal herb since ancient *** is an important ingredient in many traditional systems of ***,it is harvested for its roots,and its medicinal properties are due to the presence of diverse bioactive secondary metabolites,commonly known as *** understanding of the pharmacological properties of this intriguing genus is continuously growing due to its broad chemical *** therapeutic uses identified by traditional medicinal practice are receiving extensive *** in vitro experimental investigations of *** have reported the analgesic,anti-inflammatory,antiarrhythmic,antiparasitic and anticancer properties,as well as its effects on the central nervous *** this review,we highlight the classification,distribution,commerce,traditional uses,phytochemistry,pharmacology and conservation measures relevant to this ***,this review includes the biosynthetic pathways of ***’s key constituents,which could be targeted to enhance the expression levels of desired metabolites via genetic *** the genomics,transcriptomics,proteomics and metabolomic aspects of this species would be helpful in developing highly designed genotypes and chemotypes of this species to be used in commercial production.

关键词： Aconitum heterophyllum Ethnopharmocology Herbal medicine Phytochemistry

Stokes' First Problem for an MHD Burgers Fluid

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Communications in Theoretical Physics 2013年第1期59卷 99-104页

作者： masood Khan Department of Mathematics Quaid-i-Azam University

This work is related to the flow of a magnetohydrodynamic Burgers *** flow of an incompressible conducting Burgers fluid in the presence of a uniform transverse magnetic field over a plate that is moved suddenly is *** the application of the Laplace and Fourier sine transforms techniques,the exact analytical expressions for the velocity field and associated shear stress are determined in simple *** are written as a sum of steady-state and transient *** graphical results are plotted for different values of indispensable parameters and some interesting results are *** corresponding solutions for the hydrodynamic Burgers fluid appear as the limiting cases of the obtained solutions.

关键词： Stokes' first problem Burgers fluid Laplace and Fourier sine transforms exact solutions

MHD Flow of an Oldroyd-B Fluid through a Porous Space Induced by Sawtooth Pulses

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Chinese Physics Letters 2011年第8期28卷 161-164页

作者： masood Khan Zeeshan Department of Mathematics Quaid-i-Azam UniversityIslamabad 44000Pakistan

We investigate the unsteady magnetohydrodynamic(MHD)flow of an Oldroyd-B fluid through a porous space induced by sawtooth *** fluid is assumed to be electrically conducting in the presence of a transverse uniform magnetic *** porous space is taken into account using modified Darcy's law for the Oldroyd-B *** solutions of the governing problem are obtained by using the Laplace transform *** effects of the magnetic parameter,the permeability of the porous space and the elasticity parameter of the fluid are studied on the flow characteristics.

关键词： method field porous

Uncertainty of concrete strength in shear and flexural behavior of beams using lattice modeling

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Frontiers of Structural and Civil Engineering 2023年第2期17卷 306-325页

作者： Sahand KHALILZADEHTABRIZI Hamed SADAGHIAN masood FARZAM Department of Civil Engineering University of TabrizTabriz ***Iran

This paper numerically studied the effect of uncertainty and random distribution of concrete strength in beams failing in shear and flexure using lattice modeling,which is suitable for statistical *** independent variables of this study included the level of strength reduction and the number of members with reduced *** levels of material deficiency(i.e.,10%,20%,30%)were randomly introduced to 5%,10%,15%,and 20%of *** provide a database and reliable results,1000 analyses were carried out(a total of 24000 analyses)using the MATLAB software for each *** studies were conducted for both shear-and flexure-deficit beams under four-point loading and results were compared using finite element software where *** of lattice modeling was highlighted as an efficient tool to account for uncertainty in statistical *** showed that the number of deficient members had a more significant effect on beam capacity compared to the level of strength *** scatter of random load-capacities was higher in flexure(range:0.680-0.990)than that of shear(range:0.795-0.996).Finally,nonlinear regression relationships were established with coefficient of correlation values(R^(2))above 0.90,which captured the overall load-deflection response and level of load reduction.

关键词： lattice modeling shear failure flexural failure uncertainty deficiency numerical simulation

Predictive-reactive Strategy for Flowshop Rescheduling Problem:Minimizing the Total Weighted Waiting Times and Instability

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Journal of Systems Science and Systems Engineering 2021年第3期30卷 253-275页

作者： ayoub Tighazoui Christophe Sauvey Nathalie Sauer Universitéde Lorraine LGIPMF-57000MetzFrance

Due to the fourth revolution experiencing,referred to as Industry 4.0,many production firms are devoted to integrating new technological tools to their manufacturing *** of them,is rescheduling the tasks on the machines responding to ***,for static scheduling,the efficiency criteria measure the performance of scheduling systems,in dynamic environments,the stability criteria are also used to assess the impact of jobs *** this paper,a new performance measure is investigated for a flowshop rescheduling *** one considers simultaneously the total weighted waiting time as the efficiency criterion,and the total weighted completion time deviation as the stability *** fusion could be a very helpful and significant measure for real life industrial *** disruption types are considered:jobs arrival and jobs ***,a Mixed Integer Linear Programming(MILP)model is developed,as well as an iterative predictive-reactive strategy for dealing with the online *** last,two heuristic methods are proposed and discussed,in terms of solution quality and computing time.

关键词： Rescheduling flowshop predictive-reactive strategy weighted waiting time stability weighted completion time deviation

Pyridine-Thiourea Based High Performance Polymers: Synthesis and Characterization

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Chinese Journal of Polymer Science 2015年第1期33卷 49-60页

作者： Ghulam Waris Humaira masood Siddiqi Department of Chemistry Quaid-i-Azam University Islamabad Pakistan Department of Chemistry University of SheffieldUK

A novel diamine monomer, pyridine-2, 6-bis（（4-aminophenyl）thioureido）carbonyl（PATC） was synthesized efficiently and polymerized with various aromatic dianhydrides. Consequently, poly（pyridine thiourea-imide）s（PPTIs） with good thermal properties and flame retardancy were fabricated. The structures of PATC and PPTIs were characterized by FTIR, 1H-NMR, 13C-NMR spectroscopy along with elemental analysis, crystallinity, organosolubility, inherent viscosity and gel permeation chromatographic measurements. PPTIs containing C=S, CONH and meta substituted pyridine moieties in the polymer backbone showed amorphous nature and were readily soluble in highly polar organic solvents and even in less polar solvents such as tetrahydrofuran（THF）. Polymers had inherent viscosities in the range of 0.91-1.16 d L/g and molecular weight was found between 68000-77000 g/mol. The electrical properties of the PPTIs were estimated in terms of dielectric constant over a range of frequencies. Their thermal stability was determined by 10% weight loss temperature found in the range of 519-563 °C under inert atmosphere. The glass transition temperature of the polyimides varied between 247 °C and 267 °C. The flame retardant properties of PPTIs were investigated in terms of limiting oxygen index（LOI） which was found in the range of 38.26-39.95. Introduction of thiourea in the polymer backbone is an effective way to improve the thermal stability and flame retardancy. Thus PATC can be considered as an excellent candidate for the synthesis of high performance polymers.

关键词： Poly(pyridine thiourea-imide)s Crystallinity Flame retardancy GPC measurements.

Determination of Two-Dimensional Plastic Zone Shape and SIF at Crack-Tip Using RKPM

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Journal of Iron and Steel Research International 2013年第12期20卷 103-114页

作者： masood Hajali Caesar Abishdid Department of Civil and Environmental Engineering Florida International University Department of Civil Engineering Lebanese American University

Reproducing kernel particle Method （RKPM） is a meshless technology which has proven very useful for solving problems of elastic plastic fracture mechanics. The mode I plastic zone shape at the crack-tip in a work-hard ening material is obtained using RKPM. Ramberg-Osgood stress-strain relation is assumed and the crack-tip stress intensity factor （SIF） before and after formation of the plastic zone are examined. To impose the essential boundary conditions, penalty method is used. To construct the shape functions in the vicinity of the crack and crack-tip, both the diffraction and visibility criteria are employed. A comparison between two conventional treatments, visibility and diffraction, to crack discontinuity is conducted. The effects of different dilation parameters on SIF under plane-stress and plane-strain conditions are ~tudied. Results including plastic zone shape are compared with finite element method （FEM） to show the accuracy of RKPM. The main objective is to study the effects of different dilation parameters on SIF under plane stress and plane strain conditions and to obtain the mode I plastic zone shape at the crack-tip in a work hardening material using RKPM.

关键词： meshless reproducing kernel particle method (RKPM) crack-tip stress intensity factor (SIF) plastic zone shape

The peculiar velocity and temperature profile of galaxy clusters

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Research in Astronomy and Astrophysics 2014年第6期14卷 667-672页

作者： Tabasum masood Naseer Iqbal Department of Physics Kashmir University Inter University Centre for Astronomy and Astrophysics IUCAA

Dynamical parameters like average velocity dispersion and temperature profile of galaxy clusters are determined using the theory of quasi-equilibrium ther- modynamics. The calculated results of velocity dispersion show a good agreement between theory and simulations with the results of velocity dispersion from Abdullah et al. An adaptive mesh refinement grid-based hybrid code has been used to carry out the simulations. Our results indicate that the average velocity dispersion profile of 20 Abell galaxy clusters falls in the range of 500 - 1000 km s^-1 and their temperature profile is of the order of 10^7 to 10^8 K calculated on the basis of kinetic theory. The data in the plot show a significant contribution from gravitating particles clustering together in the vicinity of the cluster center and beyond a certain region this veloc- ity dies out and becomes dominated by the Hubble flow due to which all the galaxy clusters in an expanding universe participate in Hubble expansion.

关键词： galaxies: clusters -- gravitation -- simulations

Formation control of quad-rotor UAV via PIO

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Science China(Technological Sciences) 2022年第2期65卷 432-439页

作者： BAI TingTing WANG DaoBo masood Rana Javed College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China Department of Electrical Engineering Usman Institute of TechnologyKarachi 75850Pakistan

In this article, the formation control of quad-rotor unmanned aerial vehicle(UAV) via pigeon inspired optimization(PIO) is designed. The nonlinear mathematical model of the quad-rotor UAV is used by applying algebraic graph theory and matrix analysis. A high order consistent formation control algorithm with fixed control topology is designed by using a position deviation matrix to describe its formation. To control the attitude of quad-rotor UAVs, it is difficult to obtain a set of optimal solutions, and hence a PIO based algorithm with variable weight hybridization is proposed. The algorithm is mainly composed of two parts. First, according to the distance between the particles in the iterative process, the inertia weight is dynamically changed,and the coefficient is adjusted to control the degree of influence on its inertia weight. Second, the overall scenario is designed by using MATLAB based simulations which show that the formation control of the quad-rotor UAV is achieved with the help of PIO.

关键词： pigeon inspired optimization formation control unmanned aerial vehicle and quad-rotor UAV