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还原氧化石墨烯-硒化银纳米复合材料的水热合成与表征及其活性氧物种产生(英文)

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催化学报 2015年第4期36卷 603-611页

作者： Lei Zhu Shu Ye Asghar ali Kefayat Ulla Kwang Youn Cho Won-Chun Oh Department of Advanced Materials Science & Engineering Hanseo University Korea Institute of Ceramic Engineering and Technology

A visible-light photocatalyst containing Ag2Se and reduced graphene oxide(RGO) was synthesized by a facile sonochemical-assisted hydrothermal method. X-ray diffraction, scanning electron mi-croscopy with energy-dispersive X-ray analysis, and ultraviolet-visible diffuse reflectance spectros-copy results indicated that the RGO-Ag2Se nanocomposite contained small crystalline Ag2Se nano-particles dispersed over graphene nanosheets and absorbed visible light. The high crystallinity of the nanoparticles increased photocatalytic activity by facilitating charge transport. N2 adsorp-tion-desorption measurements revealed that the RGO-Ag2Se nanocomposite contained numerous pores with an average diameter of 9 nm, which should allow reactant molecules to readily access the Ag2Se nanoparticles. The RGO-Ag2Se nanocomposite exhibited higher photocatalytic activity than bulk Ag2Se nanoparticles to degrade organic pollutant rhodamine B and industrial dye Texbrite BA-L under visible-light irradiation(λ > 420 nm). The generation of reactive oxygen spe-cies in RGO-Ag2Se was evaluated through its ability to oxidize 1,5-diphenylcarbazide to 1,5-diphenylcarbazone. The small size of the Ag2Se nanoparticles in RGO-Ag2Se was related to the use of ultrasonication during their formation, revealing that this approach is attractive to form po-rous RGO-Ag2Se materials with high photocatalytic activity under visible light.

关键词：纳米复合材料氧化石墨水热合成氧化物活性氧硒化银可见光照射光催化活性

Evaluation of Age Related Changes in Cervical Spine in Saudi Arabian Adult Population: Using CT Scan Images

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Forensic Medicine and Anatomy Research 2014年第2期2卷 28-36页

作者： ali Hassan A. ali Mohammad Aslam Siddiqui Mohamed Abdelmohsen Bedewi Omar O. Serhan Anatomy & Radiology Departments Salman Bin Abdulaziz University Al-Kharj KSA King Khalid Hospital Al-Kharj KSA

Purpose: Cervical spine is considered to be the most moving part of vertebral column. It is located in a very important part of the body i.e. neck having some very important structures related to it. Any age related changes occurring in such a part of vertebral column may lead to many disorders and disabilities. Complete familiarity of this entire region anatomically as well as radiologically is therefore of utmost importance for the diagnosis and management of such disorders. Aim of this work is to evaluate the frequency of age related degeneration in cervical spine in Saudi adult asymptomatic subjects using CT scan images. Methods: In this study, 105 cases of symptomless adults ranging between 18 - 90 years of age were included. The cases were classified into 3 groups;adult group (18 - 35 years old), middle age group (36 - 55 years old) and old age group (56 - 90 years old). Their CT scans were performed in the department of radiology, King Khalid Hospital, Al Kharj and studied for any age related changes. Results: The first age group category included 35 cases;20 had normal and 15 degenerative changes. The second category included 35 cases;3 had normal and 32 degenerative changes. The third category included 35 cases. Single had normal and 34 degenerative changes. Conclusion: Asymptomatic degenerative changes are common in the cervical spine after 30 years of age in Saudi adult asymptomatic subjects.

关键词： Cervical Spine Age Changes Spondylosis CT

Population survey and conservation assessment of the globally threa- tened cheer pheasant （Catreus wallicht） in Jhelum Valley, Azad Kas- hmir, Pakistan

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Zoological Research 2014年第4期35卷 338-345页

作者： Muhammad Naeem AWAN Hassan ali David Charles LEE WWF Pakistan Regional Office Azad Kashmir Muzaffarabad Pakistan WWF Pakistan Feroze Pur Road Lahore Pakistan School of Applied Sciences the University of South Wales Pontypridd UK

The cheer pheasant Catreus wallichi is a globally threatened species that inhabits the western Himalayas. Though it is well established that the species is threatened and its numbers declining, updated definitive estimates are lacking, so in 2011, we conducted a survey to assess the density, population size, and threats to the species in Jhelum valley, Azad Kashmir, which holds the largest known population of cheer pheasants in Pakistan. We conducted dawn call count surveys at 17 points clustered in three survey zones of the valley, 11 of which had earlier been used for a 2002-2003 survey of the birds. Over the course of our survey, 113 birds were recorded. Mean density of cheer pheasant in the valley was estimated at 11.8±6.47 pairs per km2, with significant differences in terms of both counts and estimated density of cheer were significantly different across the three survey zones, with the highest in the Chinari region and the lowest, that is the area with no recorded sightings of the pheasants, in Gari Doppata. The total breeding population of cheer pheasants is estimated to be some 2 490 pairs, though this does not consider the actual area of occupancy in the study area. On the whole, more cheer pheasants were recorded in this survey than from the same points in 2002-2003, indicating some success in population growth. Unfortunately, increasing human settlement, fires, livestock grazing, hunting, and the collection of non-timber forest products continue to threaten the population of cheer in the Jhelum valley. To mitigate these potential impacts, some degree of site protection should be required for the conservation of cheer pheasants in Pakistan, and more effective monitoring of the species is clearly needed.

关键词： Abundance Habitat analysis Cheer Pheasant Jhelum valley Pakistan

Domination and Eternal Domination of Jahangir Graph

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Open Journal of Discrete Mathematics 2019年第3期9卷 68-81页

作者： Ramy Shaheen Mohammad Assaad ali Kassem Department of Mathematics Faculty of Science Tishreen University Lattakia Syria

In the eternal dominating set problem, guards form a dominating set on a graph and at each step, a vertex is attacked. We consider the “all guards move” of the eternal dominating set problem. In which one guard has to move to the attacked vertex and all the remaining guards are allowed to move to an adjacent vertex or stay in their current position after each attack. If the new formed set of guards is still a dominating set of the graph then we successfully defended the attack. Our goal is to find the minimum number of guards required to eternally protect the graph. We call this number the m-eternal domination number and we denote it by . In this paper we find the eternal domination number of Jahangir graph Js,m for s=2,3 and arbitrary m. We also find the domination number for J3,m .

关键词： Jahangir Graph Graph Protection Domination Number Eternal Domination

Simulation of Dual-Band MWCNT Ink-Based Spiral Antenna: A Comparative Study

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Journal of Electromagnetic Analysis and Applications 2012年第4期4卷 182-186页

作者： Taha Elsayed Taha Mohamed ali Soliman ali Mohamed Gomaa Wael Elsayed Swelam National Telecom Regulatory Authority Cairo Egypt 3Shobraa Faculty of Engineering Benha University Cairo Egypt

In this paper, we compare a dual-band, square spiral microstrip patch antenna constructed from Multi-Walled Carbon Nanotubes (MWCNT) ink for wearable application simulated by Computer Simulation Technology Microwave Studio (CST MWS) by our work simulated by Advanced Design System (ADS) electromagnetic simulator using the same material characterization. The reflection coefficient is –12 dB at 1.2276 GHz for MWCNT and –13 dB at 1.25 GHz for the copper simulated by CST MWS and reflection coefficient is –12.235 dB at 1.234 GHz for MWCNT and –18.36 dB at 1.243 GHz for the copper simulated by ADS and the reflection coefficient is –27dB at 2.47 GHz for MWCNT and –13 dB at 2.53 GHz for the copper simulated by CST MWS and the reflection coefficient is –26.08 dB at 2.48 GHz for MWCNT and –17.031 dB at 2.47 GHz for the copper simulated by ADS. We show the meandering of the surface current on the radiating in spiral patch. The antenna gain is found to be –12.5 dBi at 1.22 GHz for MWCNT and is found –12.05 dBi at 1.25 GHz at CST MWS and the antenna gain is found to be –11.85 dBi at 1.235 GHz for MWCNT and is found –12.25 dBi at 1.243 GHz at ADS and the antenna gain is found to be –4.25 dBi at 2.47 GHz for MWCNT and is found –4.01 dBi at 2.53 GHz at CST MWS and the antenna gain is found to be –4.23 dBi at 2.47 GHz for MWCNT and is found –4.88 dBi at 2.45 GHz at ADS. We show a close agreement in the results obtained by the two simulation software's CST MWS and ADS. The results are given for both MWCNT and Copper characterizations.

关键词： Copper MWCNT CST MWS ADS and Spiral Microstrip Antenna

New Frontiers of Necrotizing Enterocolitis: From Pathophysiology to Treatment

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Health 2017年第1期9卷 106-123页

作者： Umut Zubarioglu Sinan Uslu ali Bulbul Division of Neonatology Department of Pediatrics Sisli Hamidiye Etfal Educational and Research Hospital Istanbul Turkey

Necrotizing enterocolitis [NEC] is an inflammatory disease of intestine largely occuring in preterm infants with a wide range of damage from minimal injury limited to mucosa to extensive necrosis of bowel wall and perforation. Despite advancements in neonatal care, mortality remains high [30% - 50%] and controversy still persists with regards to the most appropriate management of neonates with necrotizing enterocolitis. The main factors thought to be involved in the pathogenesis of NEC are: relatively hyper-reactive state of premature intestine, enteral feeding and bacterial colonization. In this review, we discuss current knowledge about the epidemiology, pathophysiology, imaging, medical and surgical management of necrotizing enterocolitis and describe novel strategies for prevention and treatment.

关键词： Preterm Infants Necrosis Necrotizing Enterocolitis

Multi-Mode Frequency Reconfigurable Conformal Antenna for Modern Electronic Systems

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Computers, Materials & Continua 2022年第11期73卷 3861-3877页

作者： Abir Zaidi Esraa Mousa ali Abdullah G.Alharbi Salah Ud-Din Khan Mohammad Alsharef Mohammed S.Alzaidi Sherif S.M.Ghoneim Laboratory EEA&TI Faculty of Science and Techniques(FSTM)MohammediaHassan II UniversityCasablancaMorocco Faculty of Aviation Sciences Amman Arab UniversityAmman11953Jordan Department of Electrical Engineering Faculty of EngineeringJouf UniversitySakaka42421Saudi Arabia Sustainable Energy Technologies Center College of EngineeringKing Saud UniversityP.O.Box 800Riyadh11421Saudia Arabia Electrical Engineering Department College of EngineeringTaif UniversityP.O.Box 11099Taif21944Saudi Arabia

The article presents a miniaturized monopole antenna dedicated to modern flexible electronic *** antenna combines three fundamental properties in a single ***,it is characterized by a compact size compared to the state-of-the-art literature with an overall size of 18×18×0.254 mm3,secondly,the proposed antenna integrates the reconfigurability function of frequency,produced by means of a Positive-IntrinsicNegative(PIN)diode introduced into the radiating ***,the antenna is able to switch between different frequencies and different modes,making it suitable to meet the ever-changing demands of communication ***,the antenna is equipped by the property of *** fact,a conformability test is performed and has demonstrated the stability of the antenna performance under normal and bending ***,in order to demonstrate the potential of the proposed antenna,a comparison between the simulated and measured results is made and turned out to be a strong agreement,making the antenna an excellent candidate for future miniaturized rigid and conformal devices.

关键词： Monopole antenna frequency reconfigurable co-planar waveguide(CPW)fed flexible electronics compact size

Estimation of Standard Splenic Volume in Saudi Arabian Adult Population: Using 3D Reconstruction of Abdominal CT Scan Images

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Open Journal of Internal Medicine 2014年第1期4卷 7-12页

作者： Mohammad Aslam Siddiqui ali Hassan A. ali Mohamed Abdelmohsen Bedewi Omar O. Serhan Anatomy & Radiology Departments Salman bin Abdulaziz University Al-Kharj KSA Anatomy & Radiology Departments Salman bin Abdulaziz University Al-Kharj KSA Faculty of Medicine Al Azhar University Cairo Egypt King Khalid Hospital Al-Kharj KSA

Purpose: Spleen is enlarged in a variety of clinical conditions including infectious, infiltrative, immunologic and malignant states. Evaluation of splenic size is important in every physical examination of the abdomen by a physician. Determination of its size by palpation can be extremely inaccurate because spleen is never palpable till it is enlarged 2 to 3 times its own size. The accurate diagnosis of splenic enlargement is a matter of considerable importance as it is a useful guide for arriving at a diagnosis of the disease. It is therefore of utmost importance to resort to a mechanism that will give us an accurate estimation of the size of spleen. Aim of this work was to determine the normal range of spleen dimensions in average adult Saudi Arabian population and compare it with the published data. Methods: CT scans of 34 adult patients (male and female) aged between 20 - 70 years, having no splenic disorders, were collected from department of radio-diagnosis King Khalid Hospital Al-Kharj, KSA. Splenic volume was measured by two methods—by volumetric software and the prolate ellipsoid formula. Results: The average splenic volume of all subjects was 161.42 ± 54.91 cm3 with a range of 106 - 319 cm3. The average splenic volume of males was 196.95 ± 48.70 cm3 and that of female was 196.95 ± 26.97 cm3. Conclusions: These results provide normative data for evaluating patients with splenic enlargement.

关键词： Spleen 3D Reconstruction Computerized Tomography

Application of Remote Sensing and GIS in Forest Cover Change in Tehsil Barawal, District Dir, Pakistan

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American Journal of Plant Sciences 2015年第9期6卷 1501-1508页

作者： Anwar Sajjad Ahmad Hussain Umar Wahab Syed Adnan Saqib ali Zahoor Ahmad Ashfaq ali Department of Environmental Sciences University of Haripur Haripur Pakistan Department of Forestry and Wildlife University of Haripur Haripur Pakistan Institute of Geographical Information Systems National University of Sciences and Technology (NUST) Islamabad Pakistan Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory College of Plant Science and Technology Huazhong Agricultural University Wuhan China Department of Plant Pathology College of Plant Science and Technology and the Key Lab of Crop Disease Monitoring & Safety Control in Hubei Province Huazhong Agricultural University Wuhan China College of Horticulture and Forestry Sciences Huazhong Agriculture University Wuhan China

The forests of Pakistan replicate plentiful climatic, physiographic and edaphic differences in the country and these forests face a serious problem of deforestation. Geographic information system (GIS) techniques and remote sensing (RS) from satellite platforms offer a best way to identify those areas of deforestation, and thus a GIS and RS based study was conducted in tehsil Barawal, district Dir (U) to analyze forest cover change. The main objectives of the study were to: 1) identify different classes of land use and land cover, and its spatial distribution in the study area;2) determine the trend, nature, location and magnitude of forest cover change;and 3) prepare maps of forest-cover change in different time periods in the study area. To assess the objectives remote sensing and GIS techniques were utilized. A supervised image classification technique was applied on Landsat 5 satellite images of 2000 and 2012. Five main classes such as agriculture, forest, barren land, snow and water were identified. The results showed that the area of forest, barren land, agriculture, water and snow in year 2000 was 49.54%, 43.38%, 5.19%, 1.40% and 0.49% and the area in 2012 was 37.17%, 41.36%, 12.69%, 5.05% and 3.72% respectively. Furthermore 2.02% decrease in barren land, 12.37% decrease in forest and 7.5% increase in agriculture land were identified. Due to high deforestation rate and increased agricultural activities, it is recommended that awareness campaign should be launched in the study area to protect and conserve this forest from further deforestation.

关键词： Deforestation Change Analysis Forest Cover Change