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Chinese Chemical Letters 2011年第7期22卷 793-796页

作者： syed Shahed Ali Organic Laboratory Department of Sir Sayyed CollegeDr.Babasaheb Ambedkarb Marathwada UniversityAurangabad 431001India

Various 2-phenylimidazo [4,5-f] [1,10] phenanthrolines were synthesized from potassium ferro-cyanide trihydrate （KFCT） complex catalyzed three component reaction of 1,10-phenanthroline-5,6-dione, aromatic aldehydes and ammonium acetate at room temperature in excellent isolated yield. This is a simple and straight forward, high yielding, not involving any hazardous or expensive catalyst method.

关键词： 2-Phenylimidazo [4,5-f] phenanthrolines Aromatic aldehyde K4[Fe(CN)6]·3H2O Ammonium acetate

STOCHASTIC STABILITY OF UNCERTAIN RECURRENT NEURAL NETWORKS WITH MARKOVIAN JUMPING PARAMETERS

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Acta Mathematica Scientia 2015年第5期35卷 1122-1136页

作者： M.syed ALI Department of Mathematics Thiruval luvar University

In this paper, global robust stability of uncertain stochastic recurrent neural networks with Markovian jumping parameters is considered. A novel Linear matrix inequal- ity（LMI） based stability criterion is obtained to guarantee the asymptotic stability of uncertain stochastic recurrent neural networks with Markovian jumping parameters. The results are derived by using the Lyapunov functional technique, Lipchitz condition and S-procuture. Finally, numerical examples are given to demonstrate the correctness of the theoretical results. Our results are also compared with results discussed in [31] and [34] to show the effectiveness and conservativeness.

关键词： Lyapunov functional linear matrix inequality Markovian jumping parameters recurrent neural networks

Steady-state security in distribution networks with large wind farms

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Journal of Modern Power Systems and Clean Energy 2014年第2期2卷 134-142页

作者： Dilan JAYAWEERA syed ISLAM Curtin University PerthWA 6102Australia

Aging network assets,forced and unforced outages,and the way the networks are operated in a deregulated market are of significant concerns to integrate large wind farms in a distribution *** many cases,the constrained network capacity is a potential barrier to the large-scale integration of wind *** paper probabilistically assesses the steady-state security in a distribution network in the presence of large wind *** approach incorporates active distribution network operating conditions,including intermittent power outputs,random outages,demand fluctuations,and dynamic interactions and exchanges,and then assesses the steady state security using Monte Carlo simulation.A case study is performed by integrating large wind farms into a distribution *** results suggest that intermittent outputs of large wind farms in a distribution network can impact the steady-state security ***,the level of impact of wind farms does not necessarily correlate with the installed capacity of them.

关键词： Monte Carlo simulation Network integration capacity Random outages Security of supply Wind power generation

Analytical Hybrid Particle Swarm Optimization Algorithm for Optimal Siting and Sizing of Distributed Generation in Smart Grid

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Journal of Modern Power Systems and Clean Energy 2020年第6期8卷 1221-1230页

作者： syed Muhammad Arif Akhtar Hussain Tek Tjing Lie syed Muhammad Ahsan Hassan Abbas Khan the Department of Electrical and Electronic Engineering Auckland University of TechnologyAucklandNew Zealand the Department of Electrical Engineering Incheon National UniversityIncheonKorea the Department of Electrical Engineering Lahore University of Management SciencesLahorePakistan

In this paper,the hybridization of standard particle swarm optimisation(PSO)with the analytical method(2/3 rd rule)is proposed,which is called as analytical hybrid PSO(AHPSO)algorithm used for the optimal siting and sizing of distribution *** proposed AHPSO algorithm is implemented to cater for uniformly distributed,increasingly distributed,centrally distributed,and randomly distributed loads in conventional power *** demonstrate the effectiveness of the proposed algorithm,the convergence speed and optimization performances of standard PSO and the proposed AHPSO algorithms are compared for two *** the first case,the performances of both the algorithms are compared for four different load distributions via an IEEE 10-bus *** the second case,the performances of both the algorithms are compared for IEEE 10-bus,IEEE 33-bus,IEEE 69-bus systems,and a real distribution system of *** results show that the proposed AHPSO algorithm converges significantly faster than the standard *** results of the proposed algorithm are compared with those of an analytical algorithm,and the results of them are similar.

关键词： Siting and sizing of distributed generation distribution system hybrid algorithm loss minimization particle swarm optimization(PSO)

Adsorption Isotherm and Kinetic Study of Methane on Palm Kernel Shell-Derived Activated Carbon

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Journal of Bioresources and Bioproducts 2023年第1期8卷 66-77页

作者： Mohd Saufi Md Zaini Muhammad Arshad syed Shatir A.syed-Hassan School of Chemical Engineering College of EngineeringUniversiti Teknologi MARA Cawangan TerengganuKampus Bukit BesiDungun 23200Malaysia Department of Basic Science Jhang-Campus University of Veterinary and Animal ScienceLahore 35200Pakistan School of Chemical Engineering College of EngineeringUniversiti Teknologi MARAShah Alam 40450Malaysia

Activated carbon(AC)was synthesized from palm kernel shell(PKS)using different activating agents,i.e.,steam,carbon dioxide(CO 2),and CO 2-steam,in order to analyze the impact of acti-vating agents on the pore opening of *** this study,AC produced from PKS was found to have great potential as an adsorbent for methane *** different molecular diffusivity and reac-tivity of the combination of CO 2 and steam succeeded in producing AC with the highest burn-offof 78.57%,a surface area of 869.82 m 2/g,a total pore volume of 0.47 cm 3/g,and leading to maximum methane gas adsorption capacity of 4.500 mol/*** types of ACs exhibited the best fit with the Freundlich isotherm model,with the correlation coefficient(R 2)ranging from 0.997 to 0.999,indicating the formation of multilayer *** addition,the adsorption kinetic data for all ACs followed the pseudo-first-order model showing that the rate of adsorption was dependent on both the adsorbent and the adsorbate and was governed primarily by physical ad-sorption between the pore surface and methane *** results of intraparticle diffusion model indicated that the adsorption of methane was affected by both pore diffusion and exterior layer diffusion due to the different adsorption rates.

关键词： Palm kernel shell Activated carbon Methane adsorption Kinetic model Isotherm model

Magnetoelectric effect in multiferroic NdMn2O5

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Chinese Physics B 2017年第1期26卷 526-529页

作者： syed Hamad Bukhari Javed Ahmad Department of Physics Bahauddin Zakariya University Multan 60800 Pakistan

We have measured the dielectric constant for NdMn2O5 in an external magnetic field to map out the magnetoelectric phase diagram. The phase diagram corresponds well with the previously reported data of neutron diffraction and magnetic susceptibility. Our main finding is the observation of a dielectric anomaly in the low temperature phase with a strong magnetoelectric effect, which is attributed to the independent Nd^3＋ ordering. Moreover, the absence of the dielectric anomaly in the paramagnetic phase is discussed, keeping in view the exchange interaction and its dependence on the rareearth R^3＋ ionic radius.

关键词： sol–gel synthesis dielectric constant magnetoelectric effect phase transition

Helicobacter pylori associated Asian enigma: Does diet deserve distinction?

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World Journal of Gastrointestinal Oncology 2016年第4期8卷 341-350页

作者： syed Faisal Zaidi Department of Basic Medical Sciences College of Medicine King Saud bin Abdulaziz University of Health Sciences

Helicobacter pylori(H. pylori) is one of the most widespread infections in humans worldwide that chronically infects up to 50% of the world's population. The infection is involved in the pathogenesis of chronic active gastritis, peptic ulcer, mucosa-associated lymphoid tissue lymphoma and gastric cancer, therefore, it has been classified as class Ⅰ definite carcinogen by the World Health Organization. Despite the established etiological role of H. pylori, its actual distribution and association with related diseases is controversial and there is a large intercountry variation especially among Asian countries. H. pylori infection is more frequent in developing countries like India, Pakistan, and Bangladesh as compared to developed Asian countries like Japan, China and South Korea. However, the frequency of gastric cancer is comparatively lower in India, Pakistan, and Bangladesh with that of Japan, China and South Korea. Such phenomenon of clinical diversity, defined as enigma, is judged by genetic variability of the infecting H. pylori strains, differences in the host genetic background in various ethnic groups, and environmental factors such as dietary habits. Most of the studies have so far focused on the bacterial factor while environmental issues, including dietary components, were not given due attention as one of the factors related with H. pylori associated gastric carcinogenesis. The dietary factor has been suggested to play an important role in H. pylori related carcinogenesis, and in this respect several studies have corroborated the intake of various dietary components as modulatory factors for gastric cancer risk. In this review, such studies, from in vitro experiments to clinical trials, are being focused in detail with respect to enigma associated with H. pylori. It may be conceivably concluded from the available evidence that dietary factor can be a game changer in the scenario of Asian enigma, particularly in high risk population infected with virulen

关键词： Helicobacter pylori Asian enigma Gastric cancer Dietary factor Salt Fermented food Spices

Parametric relationship between hypoid gear teeth and accurate face-milling cutter

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Advances in Manufacturing 2020年第4期8卷 537-555页

作者： Mahmoud Rababah Muhammad Wasif syed Amir Iqbal Department of Mechanical Engineering Hashemite UniversityZarqaJordan Department of Industrial and Manufacturing Engineering NED University of Engineering and TechnologyKarachiPakistan

The cutter systems of hypoid gear cutting machines contain groups of inside and outside *** these cutter systems,the side cutting edges of the blades machine the convex and concave gear teeth while rotating about the cutter rotation *** side cutting edges lay on the rake face formed through the blade,rake,and relief angles;hence,the normal cross-section of the cutter swept surface forms hyperboloid gear *** the accurate geometry of the cutter system,a relationship between the pressure and spiral angles of the gear tooth and the parameters of the cutter system is developed for the FORMAT machining of a hypoid gear.A new parameterization of the gear tooth surfaces is introduced to determine these angles for the accurate gear tooth by the accurate cutter system.A numerical example with different cutter systems and blade parameters is presented,demonstrating the effects of rake and relief angles over the pressure and spiral angles on mea n point projections and gear tooth ***,the change in pressure and spiral angles with respect to the rake and relief angles are plotted,and the results are ***,it is concluded that the pressure and spiral angles are changed up to a few seconds of a degree in the operating area of the tooth with the change in the back and side rake *** side relief angle exhibited little or no effect over the geometry of the gear tooth.

关键词： Hypoid gear Pressure angle Spiral angle Accurate blade Cutter head

Carbon stocks of different land uses in the Kumrat valley, Hindu Kush Region of Pakistan

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Journal of Forestry Research 2015年第1期26卷 57-64页

作者： Adnan Ahmad syed Moazzam Nizami Shaheed Benazir Bhutto University Arid Agriculture University

Changes in land use cover, particularly from forest to agriculture, is a major contributing factor in increasing carbon dioxide（CO2） level in the *** satellite images of 1999 and 2011, land use and land use changes in the Kumrat valley KPK, Pakistan, were determined： a net decrease of 11.56 and 7.46 % occurred in forest and rangeland, while 100 % increase occurred in agriculture land（AL）. Biomass in different land uses,forest land（FL）, AL, and range land（RL） was determined by field inventory. From the biomass data, the amount of carbon was calculated, considering 50 % of the biomass as carbon. Soil carbon was also determined to a depth of 0–15and 16–30 cm. The average carbon stocks（C stocks） in all land uses ranged from 28.62 ± 13.8 t ha-1in AL to486.6 ± 32.4 t ha-1in pure Cedrus deodara forest. The results of the study confirmed that forest soil and vegetation stored the maximum amount of carbon followed by RL. Conversion of FL and RL to AL not only leads to total loss of about 56 %（from FL conversion） and 37 %（RL conversion） of soil carbon in the last decades but also the loss of a valuable carbon sink. In order to meet the emissions reduction obligations of the Kyoto Protocol, Conservation of forest and RL in the mountainous regions of the Hindu Kush will help Pakistan to meet its emissions reduction goals under the Kyoto Protocol.

关键词： Hindu Kush Kumrat valley Land uses Biomass Carbon stocks

Optimal site selection for an optical-astronomical observatory in Pakistan using Multicriteria Decision Analysis

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Research in Astronomy and Astrophysics 2019年第9期19卷 71-78页

作者： Daniyal syed Jamil Hassan Kazmi Institute of Space&Planetary Astrophysics University of Karachi75270KarachiPakistan Department of Geography University of KarachiKarachi75270Pakistan

An astronomical observatory is the core component of any astronomical research facility that connects astronomers with their lab: the Cosmos. The research quality of an astronomical facility is rooted in the precision of data, collected by its observatory. For optimal performance, an observatory is sited while considering certain astronomical, environmental, geological and social parameters. This study aims to identify the potential sites in Pakistan for locating an optical-astronomical observatory using the Multicriteria Decision Analysis(MCDA) technique. The study uses the Analytic Hierarchy Process(AHP) for deriving the influence weights of nine evaluation criteria: Photometric Night Fraction;Night-time Sky Brightness;Sky Transparency;Aerosol Concentration;Altitude;Terrain Slope;Accessibility;Seismic Vulnerability;and Landuse/Land Cover. On the basis of experts’ opinions and previous studies, the evaluation criteria have been ordered in two possible preference sequences for identifying their influence weights with respect to each other for taking part in MCDA. Consequently, the process of MCDA identified certain areas with respect to each preference sequence, whereas some areas were found to be suitable according to both preference sequences. The study synchronizes the required eclectic data into an evaluation matrix that augments the process of astronomical site selection. In the future, this study will be useful for astronomical societies and for furthering astronomical research in the country.

关键词： astronomical instrumentation methods and techniques:data analysis methods and techniques:site testing general:miscellaneous