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Investigation of ageing effects on the electrical properties of polyaniline/silver nanocomposites

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Chinese Physics B 2011年第5期20卷 424-432页

作者： asma Binat Afzal Muhammad Javed Akhtar Physics Division PINSTECHP.O.NiloreIslamabad 45650Pakistan Department of Chemical and Material Engineering PIEASIslamabad 45650Pakistan

Polyaniline（PANI）/Ag nanocomposites, synthesized by incorporation of separately prepared silver nanoparticles in 1-methyl-2-pyrrolidinone（NMP） solution of PANI, have been aged at the accelerated temperature of 120℃ to simulate a storage period of 2 years at 25℃. The accelerated ageing of these materials is done by using the activation energy calculated from data collected using heat flow calorimetry （HFC）. The impedance spectroscopic studies of NMP plasticized aged nanocomposite films suggest a microphase separation into reduced and oxidized repeat units. There is crosslinking of the lPANI films during ageing thereby obstructing the charge transfer between PANI chains and silver nanoparticles. As a result, the resistivity is increased.

关键词： polyaniline Ag nanoparticles impedance spectroscopy ageing

Bromine and oxygen redox species mediated highly selective electro-epoxidation of styrene

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Organic Chemistry Frontiers 2022年第2期9卷 436-444页

作者： Yuchi Zhang asma Iqbal Jiantao Zai Shu-Yu Zhang Hongran Guo Xuejiao Liu Ibrahim ul Islam Hira Fazal Xuefeng Qian Shanghai Electrochemical Energy Devices Research Center School of Chemistry and Chemical Engineering and State Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong University Shanghai200240P.R.China

Olefin epoxidation is an essential transformation and arouses great interest among the scientific community for the key role of epoxide in the chemical *** methods suffer from harmful oxidants and require harsh operating conditions and complex separation ***-epoxidation through bromine redox reactions is an eco-friendly ***,the lack of efficient electrodes always limits the selectivity of epoxidation and results in massive energy ***,we found that GF-CoS_(2)/CoS heterostructures anchored on graphite felt(GF-CoS_(2)/CoS)can efficiently facilitate the generation of bromine redox species on the *** synergistic cooperation between the bromine redox species and oxygen redox species(generated on a graphite rod cathode)can establish a benign electro-epoxidation system for olefin substrates in an ambient *** the optimized reaction conditions,the epoxidation of styrene can achieve a yield of 97% at 30 mA cm^(-2).Importantly,the applied voltage(4-5 V)is roughly half of the Pt-based electrode system(7.8-9.3 V),hence,saving half of the *** demonstrated that our proposed strategy could also be applied to other *** of the simple,sustainable,and economic advantages of the epoxidation process,we believe this strategy is highly desirable for technical applications.

关键词： redox epoxidation styrene

Laser-assisted ablation and plasma formation of titanium explored by LIBS,QCM, optical microscopy and SEM analyses along with mechanical modifications under different pressures of Ar and Ne

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Plasma Science and Technology 2023年第3期25卷 181-192页

作者： Maryam RIAZ Shazia BASHIR asma HAYAT Zarish NAZ Centre for Advanced Studies in Physics GC University Lahore

This study deals with the investigation of Nd:YAG laser-assisted ablation and plasma formation of Ti at irradiance of 0.85 GW cm-2 under Ar and Ne environment at various pressures ranging from 10-120 ***-induced breakdown spectroscopy is used to evaluate plasma parameters,whereas quartz crystal microbalance is used for ablation yield *** crater depth is evaluated by optical *** surface features are explored by scanning electron microscope(SEM) analysis and the micro-hardness is measured by a Vickers hardness *** is observed that the plasma parameters are higher in Ar than in Ne,and are strongly correlated with the ablation yield,ablation depth,surface features and hardness of laser-ablated *** parameters increase with increasing the pressure of environmental gases,attain their maxima at 40 Torr for Ar and at 60 Torr for ***,they show a decreasing trend up till a maximum pressure of 120 *** maximum value of the electron temperature(Te) is5480 K,number density(ne) is 1.46 × 1018 cm-3,ablation depth is 184 μm,ablation yield is3.9 × 1015 atoms/pulse and hardness is 300 HV in the case of Ar *** analysis reveals the growth of surface features,such as cones,ridges and pores,whose appearance is more distinct in Ar than Ne and is attributed to temperature,pressure and density gradients along with recoil pressure of the Ti plasma.

关键词： ablation plasma electron temperature electron density laser-induced breakdown spectroscopy surface structures

Receiving antenatal care via mobile clinic: Lived experiences of Jordanian mothers

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International Journal of Nursing Sciences 2023年第2期10卷 230-237页

作者： Hala A.Bawadi asma’a S.Abu Abed Zaid M.Al-Hamdan Safa M.Alzubi Maternal and Child Health Department School of Nursing the University of JordanAmmanJordan National Women Health Center(resigned) Royal Medical ServicesAmmanJordan Faculty of Nursing Jordan University of Science and Technology IrbidJordan Royal Medical Services AmmanJordan

Objective To understand the perceptions of pregnant Jordanian women who received antenatal care via mobile clinic,and to contribute new insights into the experiences of these mothers and how they evaluated the services that were *** Ten Jordanian mothers who had received antenatal care at a mobile clinic discussed their experiences in semi-structured,audiotaped interviews in a study that adopted a qualitative research *** analysis was done using interpretative phenomenological *** Three main themes were identified:Being informed about the medical campaign or missing the opportunity of being informed;The experience of receiving antenatal care was wonderful,although there was only one thing lacking;and they safeguard our life and take any opportunity to educate *** Data indicate that the mothers were largely satisfied with most facets of the antenatal care services they had received at the mobile ***,while services are generally well received,there are clear opportunities for ameliorating the quality of services *** mothers living in remote,deprived areas,outreach is not just an‘optional extra’but rather an essential service.

关键词： Jordan Mobile health units Pregnancy Pregnant women Prenatal care Qualitative research

Size control and electronic manipulation of Ru catalyst over B,N codoped carbon network for high-performance hydrogen evolution reaction

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Nano Research 2023年第5期16卷 6212-6219页

作者： Shuai Xu Mang Niu Guowei Zhao Shujun Ming Xingyun Li Qilong Zhu Liang-Xin Ding Minjun Kim asma A.Alothman Mohammed Sheikh Saleh Mushab Yusuke Yamauchi Institute of Materials for Energy and Environment Institute of Biochemical EngineeringCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China Hubei Key Laboratory of Processing and Application of Catalytic materials Huanggang Normal UniversityHuanggang 438000China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences(CAS)Fuzhou 350002China Guangdong Provincial Key Lab of Green Chemical Product Technology School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China Australian Institute for Bioengineering and Nanotechnology(AIBN)and School of Chemical Engineering The University of QueenslandBrisbaneQueensland 4072Australia Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia

Exploring highly efficient Pt-free catalysts for hydrogen evolution reaction(HER)is of great importance for hydrogen(H2)***,a novel HER electrocatalyst having abundant ultra-small(2–3 nm)Ru electronically confined by a B,N codoped polar carbon surface(Ru/(B-N)-PC)was *** Ru/(B-N)-PC catalyst exhibits a low overpotential of 15 mV at the current density of 10 mA·cm^(−2),a low Tafel slope of 22.6 mV·dec^(−1),superior durability,which outperforms the benchmark Pt/C *** experimental characterizations and theory calculations suggest that an electron communication established between B,N co-doped carbon surface and ultra-small Ru nanoparticles with electrons transferred from N atoms to Ru and backtransferred from Ru to B atoms,which exerts a moderate electronic modification of ***,in turn,affords a modest H adsorption energy and a lower H2O dissociation barrier,leading to the high-performance hydrogen evolution *** work provides meaningful insight into the size control and electronic modulation of Ru catalyst for intrinsic HER activity improvement.

关键词： hydrogen evolution reaction Ru catalyst carbon support doping

A STRATEGIC MODEL FOR SAFETY DURING THE HAJJ PILGRIMAGE:AN ANP APPLICATION

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Journal of Systems Science and Systems Engineering 2006年第2期15卷 201-216页

作者： asma M.A.BAHURMOZ Jeddah21423 Saudi Arabia King Abdulaziz University P.O.Box 9550

Saudi Arabia every year receives more than two million Muslims from all over the world to perform the Hajj, the Muslim pilgrimage to Makkah. It must take place during a specific period of the year in a specific and limited space. In spite of the effort government agencies devote to this event, a variety of disasters usually take place each year. As the number of pilgrims is increasing every year the problem is becoming an alarming one. More and more resources are allocated to eliminate the occurrence of such disasters. More than one strategy has been proposed to make the Hajj as safe as possible. Knowing that the problem is very complex as it involves numerous actors, and many entangled criteria and elements, the question is which strategy is best. This paper presents the Analytic Network Process as a sound methodology for structuring the Hajj problem by designing an analytical model to find which strategy to focus on to make the pilgrimage as safe as possible.

关键词： Multi-criteria decision-making Analytic Network Process pilgrimage Hajj management strategic planning Saudi Arabia

A Cross-Sectional Study on Current Practice of the Management of Pregnancy Induced Hypertension and Its Maternal and Foetal Complications and Outcome in the Western Part of the State of Libya

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Open Journal of Obstetrics and Gynecology 2022年第3期12卷 222-241页

作者： Ahmed Elghoudi Abdulrahman Alsharef asma Elghoudi College of Medicine and Health Sciences United Arab Emirates University Al Ain The United Arab Emirates Faculty of Medicine University of Tripoli Tripoli Libya

Background: Maternal and perinatal mortality and morbidity are mainly affected by hypertension during pregnancy (pre-eclampsia). Haemorrhage and cerebral bleeding are the primary and significant complications of pre-eclampsia. Abruption of the placenta and renal failure are among the major complications caused by this disease. The perinatal complications include Intrauterine Growth Restriction (IUGR), Intrauterine Foetal Death (IUFD), neonatal death, and prematurity. Objective: The purpose of the present study was to examine the incidence of Pregnancy-Induced Hypertension (PIH), pre-eclampsia, the management of PIH, including the early diagnosis, the pharmacological drug management used, and the prevalence of maternal and perinatal complications. Methods and Patients: This cross-sectional study took place in Aljalaa maternity hospital, which represented the west of the state of Libya in the period from 1st January 2012 to 31st December 2012, with patients who were diagnosed, managed, and terminated according to protocol management of the hospital. Results: In the present study, from the total deliveries in Aljalaa Maternity hospital, the incidence of PIH is 8.4% and pre-eclampsia is 5.1%. No maternal mortality, CNS haemorrhaged, hepatic failure, or renal failure. The reported maternal complications included: Eclampsia, HELLP syndrome (Haemolysis, Elevated Liver enzymes and Low platelets), abruption placenta, and pulmonary oedema see in eighteen percent, six percent, nine percent, four percent and less than one percent, respectively. The foetal complications were preterm babies and Intrauterine Growth Restriction (IUGR) in nineteen percent, Low Birth Weight (LBW) in twenty-five percent, Intrauterine Foetal Death (IUFD) in five percent, neonatal death in two percent and, perinatal death in six percent. In the PIH patients, the presence of associated symptoms such as headache, blurred vision, irritability, and the presence of signs such as severe hypertension, generali

关键词： Preeclampsia Proteinuric Pregnancy Induced Hypertension

Investigation of structural parameters and self-aggregation of Algerian asphaltenes in organic solvents

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Petroleum Science 2015年第3期12卷 509-517页

作者： asma Larbi Mortada Daaou Abassia Faraoun Laboratoire de Synthèse organique Physico-chimieBiomolcules et Environnement (LSPBE)Department of Industrial Organic ChemistryFaculty of ChemistryUniversity of Sciences and Technology of Oran Laboratoire de Chimie Physique Macromoléculaire (LCPM) Department of ChemistryFaculty of SciencesUniversity of Oran

Elemental analysis, Fourier transform infrared （FTIR）, 1H-NMR, fluorescence spectroscopy, and surface tension methods have been used to characterize the molecular structure and the aggregation behaviors of two asphaltenic fractions derived, respectively, from an Alge- rian petroleum well and a corresponding storage tank deposit. Elemental analysis, FTIR, ~H-NMR, and fluores- cence spectroscopy were used to investigate the chemical composition and structural parameters of asphaltenes, while the surface tension method was used to measure the critical micelle concentration （CMC） in organic solvents with different solubility parameters and polarities in order to characterize the asphaltenes＇ aggregation behaviors. Results show that the unstable asphaltenes fraction extracted from the storage tank deposit possesses a higher polarity （higher heteroatoms content） and a lower aro- maticity than stable asphaltenes from the petroleum well. The CMC results indicate that asphaltenes with high polarity and low aromaticity have a high solubility in polar solvents such as nitrobenzene, whereas asphaltenes with low polarity and high aromaticity are more soluble in solvents with weak polarity, like toluene. It is concludedthat the difference of structure of asphaltene samples and polarity of solvents can lead to difference of aggregation behaviors.

关键词： Asphaltenes Algerian petroleum Structural parameters - CMC

The Use of Artificial Intelligence for Disasters

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Open Journal of Applied Sciences 2023年第5期13卷 731-738页

作者： asma Salman Alruqi Mehmet Sabih Aksoy Information Systems Department King Saud University Riyadh Saudi Arabia

In recent years, due to an increasing number of extreme meteorological events, the urgent need to use artificial intelligence in their management has emerged. The ability to handle and prevent such events requires disaster management. Artificial intelligence is extensively used in forecasting and preparing for disasters, as well as for mitigating and minimizing damage and in the response phase to effectively help in better and more rapid responses to disasters. This paper examines to identify the uses of artificial intelligence technologies in reducing the impact of various disasters and seeks to investigate the possibility of linking artificial intelligence technologies based on information and communication technology and reducing the effects of disasters. We conclude the paper with the challenges facing artificial intelligence technologies.

关键词： Artificial Intelligence Disaster Management GIS