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GRAFTING OF POLY(SODIUM STYRENESULFONATE) ONTO GOLD SURFACE FROM NaNO_3 SOLUTION

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Chinese Journal of Polymer Science 2011年第5期29卷 575-579页

作者： Iram bibi Mohammad Siddiq Department of Chemistry Quaid-i-Azam University Islamabad 45320Pakistan

The chemical grafting of thiol terminated poly（sodium styrenesulfonate）（HS-PSSS） chains from sodium nitrate （NaNO3） salt solution to a gold surface was investigated with a quartz crystal microbalance with dissipation monitoring （QCM-D） in different salt concentrations, It was found that at low salt concentration grafting density of HS-PSSS was low and the grafted chains adopted a mushroom conformation. With the increase of salt concentration polyelectrolyte chains underwent a transition toward coiled state due to reduction of electrostatic repulsion and as a result more chains were grafted on the surface, When the grafting density reached a certain limit after which further grafting caused repulsion between already grafted HS-PSSS chains and as a result grafted chains adopted a brush conformation.

关键词： Poly(sodium styrenesulfonate) Quartz crystal microbalance Kinetics of grafting.

Compatibility and optoelectronic of ZnSe nano crystalline thin film

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Chinese Physics B 2012年第9期21卷 460-465页

作者： Taj Muhammad Khan Tayyaba bibi National Institute of Laser and Optronics(NILOP) Department of Chemistry Peshawar University

We report the room temperature synthesis of zinc selenide （ZnSe） nano crystalline thin film on quartz by using a relatively simple and low cost closed space sublimation process （CSSP）. The compatibility of the prepared thin films for optoelectronic applications was assessed by X-ray diffraction （XRD）, atomic force microscope （AFM）, scanning electron microscope （SEM）, Raman spectroscopy, photoluminescence, and Fourier transform infrared spectroscopy （FT-IR）. The XRD confirmed that the films were polycrystalline with the preferential orientation along the （111） plane corresponding to the cubic phase （2θ = 27.28°）. The AFM indicated that the ZnSe film presented a smooth and compact morphology with RMS roughness 19.86 nm. The longitudinal optical phonon modes were observed at 247 cm^-1 and 490 cm^-1 attributed to the cubic structured ZnSe. The Zn-Se stretching band was confirmed by the FT-IR. The microstructure and compositional analysis was made with the SEM. The grain size, dislocation density, and strain calculated were co-related. All these properties manifested a good quality, high stability, finely adhesive, and closely packed structured ZnSe thin film for optoelectronic applications.

关键词： thin film Raman spectroscopy

QML Estimation of Asymmetric Markov Switching GARCH(p,q) Processes

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Communications in Mathematics and Statistics 2021年第4期9卷 405-438页

作者： Abdelouahab bibi Department of Mathematics Universite Larbi Ben M’hidi O.E.B.Oum El BouaghiAlgeria

In this paper,I propose a natural extension of time-invariant coefficients threshold GARCH(TGARCH)processes to time-varying one,in which the associated volatility switch between different regimes due to dependency of its coefficients on unobservable(latent)time homogeneous Markov chain with finite state space(MS-TGARCH).These models are showed to be capable to capture some phenomena observed for most financial time series,among others,the asymmetric patterns,leverage effects,dependency without correlation and tail ***,some theoretical probabilistic properties of such models are discussed,in particular,we establish firstly necessary and sufficient conditions ensuring the strict stationarity and ergodicity for solution process of ***,we extend the standard results for the limit theory of the popular quasi-maximum likelihood estimator(QMLE)for estimating the unknown parameters involved in model and we examine thus the strong consistency of such *** finite-sample properties of QMLE are illustrated by a Monte Carlo *** proposed model is applied to model the exchange rates of the Algerian Dinar against the single European currency(Euro).

关键词： MS-TGARCH model Strict stationarity Strong consistency

Distribution pattern and ecological determinants of an invasive plant Parthenium hysterophorus L., in Malakand division of Pakistan

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Journal of Mountain Science 2020年第7期17卷 1670-1683页

作者： Nasrullah KHAN Khudija bibi Rafi ULLAH Department of Botany University of MalakandChakdara 18800 District Dir LowerKhyber PakhtunkhwaPakistan Swiss Federal Institute for Forest Snow and Landscape ResearchZuercherstrasse 1118903BirmensdorfSwitzerland

After habitat loss,drastic effects of biological invasion caused by alien invasive species to the native biodiversity have been acknowledged worldwide by the agriculturists,ecologists,and governments as it is more overwhelming than pollution,harvest and disease *** such example of biological invasion is *** which is considered to be one of the topmost noxious weeds threatening ecosystems diversity in the world,particularly in Pakistan due to its invasive success and generalist *** no studies have explored the pattern and determinants of plant biodiversity in the Parthenium dominated *** we explored the current distribution pattern of this species with relation to environmental variables in the Malakand division of northern ***-three sites dominated by *** were identified through a participatory mapping process combined with traditional ecological knowledge and quantitative inventories were *** total,we found 62 plant species in 55 genera and 32 families,predominately from Asteraceae,Poaceae,and ***’s agglomerative clustering procedure showed three well-differentiated,and ecologically meaningful but overlapping vegetation *** was found to be the leading species with an average Importance value ranging from 33.28%to 65.59%.Based on our criteria,surprisingly we found significantly less to be fully(30%)or partially invaded(21%)than the less invaded(47%)plots,indicating the gradual invasive success of the species across the *** Correspondence Analysis(CCA-ordination)has explained 36.9%of the cumulative variance by the first three axes and identified elevation(r=-0.526),slope(r=0.438)and percent sand(r=-0.474)to be the major environmental factors affecting the distribution of *** and associated *** results suggested that elevation and percent sand negatively affect Parthenium distribution whereas slope has a positive relationship

关键词： Habitat lost Biological invasion Parthenium hysterophorus Multivariate analysis Conservation and Management

Frequency-Domain Estimation of Continuous-Time Bilinear Processes

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Communications in Mathematics and Statistics 2021年第4期9卷 379-403页

作者： Abdelouahab bibi Fateh Merahi Department of Mathematics Larbi Ben M’hidi UniversityOum El BouaghiAlgeria Department of Mathematics Abbes Laghrour UniversityBP 1252 Route de Batna40004 KhenchelaAlgeria

In this paper,we study in frequency domain someprobabilistic and statistical properties of continuous-time version of the well-known bilinear processes driven by a standard Brownian *** class of processes which encompasses many commonly used processes in the literature was defined as a nonlinear stochastic differential equation which has raised considerable interest in the last few ***,the L_(2)-structure of the process is studied and its covariance function is *** structures will lead to study the strong consistency and asymptotic normality of the Whittle estimates of the unknown parameters involved in the *** sample properties are also considered through Monte Carlo *** end,the model is then used to model the exchanges rate of the Algerian Dinar against the US dollar.

关键词： Continuous-time bilinear processes Whittle estimator Consistency Asymptotic normality

Quantum carpets:efficiently probing fractional revivals in position-dependent mass systems

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Communications in Theoretical Physics 2023年第1期75卷 46-54页

作者： Tooba bibi Sunia Javed Shahid Iqbal Department of Physics School of Natural SciencesNational University of Sciences and TechnologyH-12 IslamabadPakistan

Position-dependent-mass systems are of great importance in many physical situations,such as the transport of charge carriers in semiconductors with non-uniform composition and in the theory of many-body interactions in condensed *** we investigate,numerically and analytically,the phenomenon of fractional revivals in such systems,which is a generic characteristic manifested by the wave-packet evolution in bounded Hamiltonian *** the fractional revivals using specific probes is an important task in the theory of quantum measurement and *** numerically simulate the temporal evolution of probability density and information entropy density,which manifest self-similarly recurring interference patterns,namely,quantum *** numerical results show that the quantum carpets not only serve as an effective probe for recognizing the fractional revivals of various order but they efficiently describe the effect of spatially-varying mass on the structure of fractional revivals,which is manifested as a symmetry breaking in their designs.

关键词： wave-packet dynamics quantum carpets information carpets quantum revivals fractional revivals position-dependent mass schroedinger equation

MICELLAR PARAMETERS OF DIBLOCK COPOLYMERS AND THEIR INTERACTIONS WITH IONIC SURFACTANTS

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Chinese Journal of Polymer Science 2012年第2期30卷 217-226页

作者： Noor Rehman Abbas Khan Iram bibi Mohammad Siddiq Department of Chemistry Quaid-I-Azam UniversityIslamabad 45320Pakistan Instituto de Quimica Universidade Federal do Rio Grande do SulUFRGS PO Box 15010CEP 91501-930Porto Alegre/RS/Brazil Department of Chemistry Abdul Wali Khan UniversityMardan K-PukhtoonkhwaPakistan

The interactions of non-ionic amphiphilic diblock copolymer poly（oxyethylene/oxybutylene）（E39B18） with anionic surfactant sodium dodecyl sulphate （SDS） and cationic surfactant hexadecyltrimethylammonium bromide （CTAB） were studied by using various techniques such as surface tension, conductivity, steady-state fluorescence and dynamic light scattering. Surface tension measurements were used to determine the critical micelle concentration （CMC） and thereby the free energy of micellization （AGmic）, free energy of adsorption （AG^ds）, surface excess concentration （F） and minimum area per molecule （A）. Conductivity measurements were used to determine the critical micelle concentration （CMC）, critical aggregation concentration （CAC）, polymer saturation point （PSP）, degree of ionization （tr） and counter ion binding （l]）. Dynamic light scattering experiments were performed to check the changes in physiochemical properties of the block copolymer micelles taken place due to the interactions of diblock copolymers with ionic surfactants. The ratio of the first and third vibronic peaks （11/Is） indicated the polarity of the pyrene micro environment and was used for the detection of micelle as well as polymer-surfactant interactions. Aggregation number （N）, number of binding sites （n） and free energy of binding （AGb） for pure surfactants as well as for polymer-surfactant mixed micellar systems were determined by the fluorescence quenching method.

关键词： Surface tension Conductivity Dynamic light scattering steady-state fluorescence Micellization.

Effects of turmeric(Curcuma longa)and its constituent(curcumin)on the metabolic syndrome:An updated review

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Journal of Integrative Medicine 2022年第3期20卷 193-203页

作者： Zeinab Vafaeipour bibi Marjan Razavi Hossein Hosseinzadeh Student Research Committee Mashhad University of Medical SciencesMashhad ***Iran Department of Pharmacodynamics and Toxicology School of PharmacyMashhad University of Medical SciencesMashhad ***Iran Targeted Drug Delivery Research Center Pharmaceutical Technology InstituteMashhad University of Medical SciencesMashhad ***Iran Pharmaceutical Research Center Pharmaceutical Technology InstituteMashhad University of Medical SciencesMashhad ***Iran

Metabolic syndrome(MS)involves people with the following risk factors:obesity,hypertension,high glucose level and *** can increase the risk of heart disease,stroke and type 2 diabetes *** prevalence of MS in the world’s adult population is about 20%–25%.Today,there is much care to use medicinal ***(Curcuma longa)as well as curcumin which is derived from the rhizome of the plant,has been shown beneficial effects on different components of ***,the purpose of this manuscript was to introduce different in vitro,in vivo and human studies regarding the effect of turmeric and its constituent on ***,different mechanisms of action by which this plant overcomes MS have been *** on studies,turmeric and its bioactive component,curcumin,due to their anti-inflammatory and antioxidant properties,have antidiabetic effects through increasing insulin release,antihyperlipidemic effects by increasing fatty acid uptake,anti-obesity effects by decreasing lipogenesis,and antihypertensive effects by increasing nitric *** to several in vivo,in vitro and human studies,it can be concluded that turmeric or curcumin has important values as a complementary therapy in ***,more clinical trials should be done to confirm these effects.

关键词： Turmeric Curcuma longa Curcumin Metabolic syndrome Diabetes Hyperlipidemia

On new classes of strongly Janowski type functions of complex order

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Applied Mathematics(A Journal of Chinese Universities) 2023年第1期38卷 89-99页

作者： Khalil Ahmad Khudija bibi M.Sajjad Shabbir Department of Mathematics Air UniversityPAF-ComplexSector E-9IslamabadPakistan Department of Mathematics Faculty of Basic and AppliedInternational Islamic University IslamabadPakistan Department of Mathematics University of Poonch RawalakotAzad Kashmir 12350Pakistan

We investigate some new subclasses of analytic functions of Janowski type of complex *** also study inclusion properties,distortion theorems,coefficient bounds and radius of convexity of the ***,analytic properties of these classes under certain integral operator are also *** findings are more comprehensive than the existing results in the literature.

关键词： subordination Janowski function starlike function convex function complex order