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Interface evolution in the platelet-like SiC@C and SiC@ SiO2 monocrystal nanocapsules

Nano Research 2017年第8期10卷 2644-2656页

作者： Jian Gao Jieyi Yu Lei Zhou Javid muhammad Xinglong Dong Yinong Wang Hongtao Yu Xie Quan Shaojie Li Youngguan Jung Key Laboratory of Materials Modification by Laser Ion and Electron Beams (Ministry of Education) School of Materials Science and Engineering Dalian University of Technology Dalian 115023 China Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) School of Environmental Science and Technology Dalian University of Technology Dalian 116024 China InstrumentalAnalysis and Research Center Dalian University of Technology Panjin 124221 China Department of Mechanical Engineering Kumoh National Institute of Technology Daeharkro 53 Gumi Gyeong-Buk 730-701 Republic of Korea

Carbon-coated SiC@C nanocapsules （NCs） with a hexagonal platelet-like morphology were fabricated by a simple direct current （DC） arc-discharge plasma method. The SiC@C NCs were monocrystalline, 120-150 nm in size, and approximately 50 nm thick. The formation of the as-prepared SiC@C NCs included nucleation of truncated octahedral SiC seeds and subsequent anisotropic growth of the seeds into hexagonal nanoplatelets in a carbon-rich atmosphere. The disordered carbon layers on the SiC@C NCs were converted into SiO2 shells of SiC@SiO2 NCs by heat treatment at 650 ℃ in air, during which the shape and inherent characteristics of the crystalline SiC core were obtained. The interface evolution from carbon to SiO2 shells endowed the SiC@SiO2 NCs with enhanced photocatalytic activity due to the hydrophilic and transparent nature of the SiO2 shell, as well as to the photosensitive SiC nanocrystals. The band gap of the nanostructured SiC core was determined to be 2.70 eV. The SiC@SiO2 NCs degraded approximately 95% of methylene blue in 160 min under visible light irradiation.

关键词： silicon carbide silicon oxide nanocapsule monocrystal photocatalyst

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Three-Layer Multi-UAVs Path Planning Based on ROBL-MFO

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Guidance, Navigation and Control 2022年第3期2卷 106-134页

作者： Salvador N.Obama Oyana Jun Li muhammad Usman Department of Automation University of Science and Technology of ChinaHefei 230026P.R.China

This paper proposes a new three-layer path planning method,where we fused two existing path planning methods(global path and local path)into a single problem for multi-unmanned aerial vehicles(UAVs)path planning for *** global-path network layer contains the latest information and algorithms for global planning according to specific *** trajectory planning layer represents the kinematics and different motion characteristics,the planningexecution layer implements the local planning algorithm for obstacle *** the last layer,we propose a new swarm intelligence algorithm called the refraction principle and opposite-based-learning moth flame optimization(ROBL-MFO).In contrast to the classical MFO,the proposed algorithm addresses the shortcoming of the classical MFO ***,it adapts the moth position update formula to the notion of historical optimal flame average and improves the convergence speed of the ***,it utilizes a random inverse learning strategy to narrow down the search ***,the principle of refraction gives the algorithm the ability to jump out of local optima and helps the algorithm avoid premature *** experimental results show that the performance of the proposed algorithm is versatile,robust,and stable.

关键词： Refraction principle and opposite-based-learning moth flame optimization multiUAVs optimal path planning three-layer

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Identification of Potential F<sub>1</sub>Hybrids in Maize Responsive to Water Deficient Condition

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American Journal of Plant Sciences 2014年第13期5卷 1945-1955页

作者： Fahad Masoud Wattoo muhammad Saleem muhammad Sajjad Department of Plant Breeding and Genetics University of Agriculture Faisalabad Faisalabad Pakistan Department of Plant Breeding and Genetics University of Arid Agriculture Rawalpindi Pakistan

The assessment of heterotic F1 combinations is a basic requisite for hybrid seed development. A set of 30 F1 hybrids along with their parental inbred lines were evaluated under both normal and water deficit conditions for various physiological and agronomic traits. Highly significant mean squares due to general combining ability, specific combining ability and reciprocal effect were observed for all traits under both water regimes. Components of variation exhibited greater estimates for GCA variance (б2g) than SCA variance (б2s) for majority of the traits under both normal and stress conditions depicting the predominant role of additive genetic component. Inbred lines NCIL-20-20, D-157 and OH-8 were found to be the best general combiner on the basis of performance regarding grain yield per plant under water deficit condition. The F1 combinations namely, NCIL-20-20 × D-109, NCIL-20-20 × OH-8 and D-157 × NCIL-20-20 were out-performers based on yield and yield attributes under water deficit conditions. On the basis of our results, we recommend these hybrids for further exploitation to assess their potential for commercial cultivation under water deficit condition.

关键词： Maize General Combining Ability (GCA) Specific Combining Ability (SCA) Water Stress Inbred Lines

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User growth and penetration modeling for converged heterogeneous network

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Journal of Beijing Institute of Technology 2013年第3期22卷 361-366页

作者： SADIA Murawwat 赵三元岳雷张超薛丞博 muhammad Imran Malik 沈庭芝 School of Information and Electronics Beijing Institute of Technology

To evaluate the trail potential of converged heterogeneous network （CHN） market, the logistic method for adoption modeling of CHN is used. User growth ＆ penetration have been taken as two variants to find saturation condition in market. Model is continuous in time but modifications are done for discrete recurrence equation, commonly known as logistic map. Dynamic and static phases are taken into consideration while penetration decay is not covered in this model.

关键词： convergence heterogeneous network logistic model user growth user penetration

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Gnomon Assessment for Geographic Coordinate, Solar Horizontal &Equatorial Coordinates, Time of Local Sunrise, Noon, Sunset, Direction of Qibla, Size of Earth &Sun for Lahore Pakistan

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Open Journal of Applied Sciences 2016年第2期6卷 100-111页

作者： muhammad Usman Saleem College of Earth and Environmental Sciences Institute of Geology University of the Punjab Lahore Pakistan

This study was an effort to calculate geographic coordinates, solar horizontal and equatorial cooridnates, direction of Qibla, sizes of Earth and Sun through gnomon (a vertical stick casting shadow). Gnomon has been used in history for remote navigations, astronomical and geodetic measurements. Geographic coordinates were found out with accuracy of less than 0.19 decimal degree from gnomon. Sun’s horizontal and equatorial coordinates were calculated and analyzed with US Navy Observatory and NOAA Earth System Research Laboratory. These coordinates were less than 0.01 decimal degree different from coordinates provided by US Navy and following same daily trend with time. Through spherical triangle, direction of Qibla was found out. And it came out less than 0.18 decimal degree different from its value, used in Lahore. Radius of the earth measured from gnomon using concepts of Al Buruni was 1.45 km different from its true value. Using geometrical technique of similar and concurrent triangles, size of the sun was calculated and it was 1,651,088.776 km. Investigation of systematic and random errors in each calculation was the part of this research.

关键词： Geographic Coordinates Sun Horizontal and Equatorial Coordinates Direction of Qibla Size of the Earth Gnomon Measurements

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Design of a Compact Monopole Antenna for UWB Applications

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Computers, Materials & Continua 2021年第1期66卷 35-44页

作者： Naeem Ahmad Jan Saad Hassan Kiani Daniyal Ali Sehrai muhammad Rizwan Anjum Amjad Iqbal Mujeeb Abdullah Sunghwan Kim Department of Electrical Engineering Iqra National UniversityPeshawar25000Pakistan Department of Electrical Engineering City University of Science and Information TechnologyPeshawar25000Pakistan Department of Electronic Engineering The Islamia University of BahawalpurBahawalpur63100Pakistan Department of Electrical Engineering Multimedia UniversityCyberjaya63100Malaysia Department of Computer Science Bacha Khan UniversityCharsadda24420Pakistan School of Electrical Engineering University of UlsanUlsan44610Korea

In this paper,a low cost,highly efficient and low profile monopole antenna for ultra-wideband(UWB)applications is presented.A new inverted triangular-shape structure possessing meander lines is designed to achieve a wideband response and high *** design the proposed structure,three steps are utilized to achieve an UWB *** bandwidth of the proposed antenna is improved with changing meander lines parameters,miniaturization of the ground width and optimization of the feeding *** measured and simulated frequency band ranges from 3.2 to 12 GHz,while the radiation patterns are measured at 4,5.3,6 and 8 GHz frequency *** overall volume of the proposed antenna is 26×25×1.6 mm^(3);whereas the FR4 material is used as a substrate with a relative permittivity and loss tangent of 4.3 and 0.025,*** peak gain of 4 dB is achieved with a radiation efficiency of 80 to 98%for the entire *** modelling of proposed antenna is performed in ANSYS HFSS 13 software.A decent consistency between the simulated and measured results is accomplished which shows that the proposed antenna is a potential candidate for the UWB applications.

关键词： Ultra-wideband(UWB) meander lines monopole antenna high efficiency high gain ANSYS HFSS

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Knowledge and practices of primary care physicians on the current referral system of diabetic retinopathy in Islamabad and Rawal-Pindi, Pakistan

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International Journal of Ophthalmology(English edition) 2019年第12期12卷 1885-1892页

作者： muhammad Shakaib Anwar Baila Shakaib Waseem Akhtar Erum Yusufzai Maham Zehra Hajira Munawar Kinza Azhar Department of Ophthalmology Rawal Institute of Health and SciencesIslamabad 44000Pakistan Medical College Rawal Institute o f Health and SciencesIslamabad 44000Pakistan

AIM: To assess the current knowledge and practices in diabetic eye care and referral system regarding diabetic retinopathy(DR) in health centers of Islamabad and RawalPindi. METHODS: A cross-sectional study was carried out in 4 government and private health centers in RawalpindiIslamabad from May 2018 to Oct. 2018. A total of 38 Primary Care Physicians(general practitioners, family physicians, and internists) were recruited out of which data for 2 were either not returned, or were missing partially. Data were collected through a 27-item consented & validated, multiple-choice questionnaire based on physician characteristics, knowledge and practice of diabetic eye care and challenges faced due current DR referral system. Descriptive analyses for all variables were performed including, mean and standard deviation. Analytical analyses were also conducted to study association between different study variables. RESULTS: Mean scores of knowledge for general practitioners, family physicians, and internists were 41.7%, 42.0% and 46.6% respectively. A lack of knowledge, and suboptimal practices were observed regarding signs, symptoms, screening, testing, evaluation and referral of DR regardless of physicians’ specialty, or years in practice. Lack of expertise regarding direct ophthalmoscopy, interpretation of findings, and referral to an ophthalmologist were noted. Physicians who performed consultation and counselling according to patients’ needs referred more patients to an ophthalmologist than those who restricted their consultationto a fixed amount of time and had more patients per unit time(P=0.01). Physicians who had taken care of less than 5 number of patients with DR marked less incorrect answers with no significantly greater number or correct answers compared to physicians who had taken care of more than 5 number of patients with DR(P=0.044). An association of more than 5 patients with DR taken care of with more need based patient consultation and counselling was also

关键词： diabetic retinopathy referral of diabetic retinopathy diabetic retinopathy guidelines primary care physicians

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Cement Resources, Agrominerals, Construction, Marble, Dimension and Decor Stone Resources, Gemstone and Jewelry Resources of Pakistan

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Open Journal of Geology 2020年第8期10卷 900-942页

作者： muhammad Sadiq Malkani Geological Survey of Pakistan Muzaffarabad Azad Kashmir Pakistan

Large deposits of cement raw material and resources like limestone, gypsum and shales/clays found from the Koh Sulaiman area of South Punjab (Saraikistan) and Balochistan Provinces, Pakistan. The installation of cement industries especially in South Punjab/Saraikistan Province due to close occurrences of resources should develop the area and increase the export. The Koh Sulaiman regions of South Punjab (Saraikistan) have huge gypsum deposits which deserve for further exploitation. Pakistan is agricultural country and fertility of cultivated lands is vital. Fertilizer resources like phosphate deposits are moderate but the deposits of phosphate and potash bearing rocks are very vast and need their further explorations and exploitation in the Indus Basin. Pakistan has very large construction, dimension and decor stone deposits like limestone, marble, dolomite and igneous rocks like granite, dolerite, serpentine, etc. which needs further exploitation for the development of the areas and increase export. Pakistan is spending a lot of earnings for importing glass, glass wares, pottery, clay, etc. while Pakistan has these resources which needs exploitation of own resources. The best structures and geotectonic elements like the Northern and Western Indus Sutures and Karakoram Suture and Indus placers which are rich in gemstones and jewelry resources. To increase gems and jewelry export, these industries requires reduction in gemstones smuggling and encouragement for gem appraisal and jewelry industry at high level for value addition. In short, Pakistan is rich in natural resources but poor in development. Try should be made to develop and export the own mineral commodities like cement, gypsum, marble, gemstones and jewelry.

关键词： Cement Resources Agrominerals Construction Marble Dimension and Decorstone Resources Gems and Jewelry Resources Export Value Addition Pakistan

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Matching effect in superconducting NbN thin film with a square lattice of holes

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Chinese Physics B 2009年第10期18卷 4486-4489页

作者： muhammad Kamrana 何世坤张伟君曹文会李博宏康琳陈健吴培亨邱祥冈 Institute of Physics Chinese Academy of Sciences and Beijing National Laboratory of Condensed Matter Physics Research Institute of Superconducting Electronics Department of Electronic Science & Engineering Nanjing University

A square hole array is fabricated over a micro-bridge of NbN thin film by electron beam lithography and reactive ion milling. Magneto-resistance is measured across the micro-bridge filled with a hole array near the superconducting transition temperature. It is found that magneto-resistance minima occur when the number of vortices is an integer multiple or a fractional multiple of the number of holes. The temperature and the current dependences of the matching effect are studied.

关键词： flux pinning superconducting thin film matching effect

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ZrO2催化无溶剂条件下醇的液相氧化反应

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催化学报 2007年第5期28卷 413-416页

作者： Mohammad ILYAS Mohammad SADIQ Imdad khan 白沙瓦大学国家卓越物理化学研究中心白沙瓦25120巴基斯坦

采用一种环境友好的方法,以分子氧为氧化剂,以ZrO2为催化剂,在无溶剂的条件下实现了醇的选择性氧化.苯甲醛、环己酮和辛醛等是相应醇的主要氧化产物.考察了不同反应条件（搅拌速度、反应时间和温度）、催化剂制备参数（焙烧温度和负载... 详细信息

采用一种环境友好的方法,以分子氧为氧化剂,以ZrO2为催化剂,在无溶剂的条件下实现了醇的选择性氧化.苯甲醛、环己酮和辛醛等是相应醇的主要氧化产物.考察了不同反应条件（搅拌速度、反应时间和温度）、催化剂制备参数（焙烧温度和负载量）及氧分压等的影响.结果发现,对于醇氧化生成相应羰基化合物,1 223 K焙烧的ZrO2比723 K焙烧的ZrO2显示出更高的催化活性.催化剂在反应混合物中不溶解,可以通过简单的过滤使其分离并重复使用.当搅拌速度大于900 r/min时,对醇的转化速率无明显的影响.

关键词：氧化锆无溶剂液相氧化醇

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