A New Dental Superalloy System: II. Mechanical Properties

Cobalt-base alloys strengthened by intermetallic compounds of tantalum were prepared and tested. Some of the alloys were stronger and more ductile than conventional base-metal alloys.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66613/2/10.1177_00220345730520010801.pd

Design and analysis of piping system for an open channel flume’s flow

The increase on the usage of non-renewable energy has caused high demanding on energy supplies. This demand is highly needed for the industrial, transportation, domestic usage and etc. Shortage in the non-renewable energy had caused human to find other alternatives to generate energy. Hence, this research is aim to develop a flume, that later use to generate electricity. However, researcher only focuses on the design and analysis of the piping system of the flume. The objectives of this research is to design piping system of an open channel with less head losses and simulate it using CFD for only single phase perform (not free service), to evaluate the pressure drop in the pipes and to analyses and determine the head losses in the pipe. The instrument used is Solid Work 2012 for technical drawing of the piping system and Computational Fluid Dynamics (CFD) for simulation of the design and analysis. There are four designs of piping system that had been produce which is Design A, Design B, Design C and Design D, the properties measured for all four designs are pressure drop, percentage pressure drop, head loss and velocity. Design A; average percentage of pressure drop is 40.2%, average head loss which is 2.7 m, velocity; inlet velocity is 8.84 m/s and average outlet velocity is 8.75 m/s. Design B; average percentage of pressure drop is 53.6 %, average head loss which is 5.8 m, velocity; inlet velocity is 8.84 m/s and average outlet velocity is 14.31 m/s. Design C; percentage of pressure drop is 38.4 % ,head loss which is 4.4 m, velocity; inlet velocity is 8.84 m/s and outlet velocity is 11.76 m/s. Designs D; percentage of pressure drop is 30.7%, head loss which is 3.1 m, velocity; inlet velocity is 8.84 m/s and outlet velocity is 12.03 m/s. The best design is determined by less percentage of pressure drops, hence from the research findings Design D is the best design since it has the less percentage of pressure drop

The application of variable speed limits to arterial roads for improved traffic flow

Traffic congestion problems continue to increase in large cities due to rapidly increasing travel demand and a lack of transport infrastructure. Congestion causes mobility and efficiency loss, safety reduction, increased fuel consumption and excessive air pollution. A number of traffic management strategies have been proposed and some are applied in cities, such as diverting traffic from peak periods to off-peak periods using congestion pricing, reduced speed limits, coordinated traffic signals along major arterial roads, or adding additional lanes where network expansion is feasible. Among the many solutions to traffic congestion, operational treatments for existing road networks provide more cost efficient traffic operation due to their relatively low cost. This research looks to improve efficiency through the application of Variable Speed Limits (VSLs). While VSLs have been used to improve traffic conditions on congested motorways in terms of mobility, safety and travel time, they are largely untested on signalized urban arterial roads. Griffith Arterial Road (GAR) U20 was selected as the case study for the research. GAR is part of the Brisbane Urban Corridor (BUC), and is approximately 11.5 km long and lies between the Gateway Motorway and the Ipswich Motorway. The average daily traffic volume (ADT) is between 18,000 vehicles to 24,000 vehicles. The number of lanes at approaches to signalised intersection varies from 1 to 4. In the context of this research, the study used STREAMS data and real world data collected using six high definition (HD) video cameras to develop a VISSIM model and to discern the effectiveness of applying VSL control. VISSIM is a time step and a psycho-physical car following model developed to model urban traffic and public transit operations. The VISSIM model was extensively calibrated and validated with the empirical data collected regarding measure of effectiveness such as traffic volumes, volume distribution, and saturated headway along the west bound (WB) and eastbound (EB) directions. The simulated model allowed the testing of different control strategies for VSL and Integrated Traffic Control System (ITCS) under different scenarios and circumstances. It helped to contrast the traffic flow parameters of invariant (no controlled speed) and VSL (controlled speed) conditions. Multiple simulation runs were considered in the calibration and evaluation process. The measures of effectiveness used to characterise the operational quality of signalized intersections were delay, queue length, and number of stops. In addition, flow, speed and density parameters were used to characterise the changes in traffic performance for the arterial road. This thesis investigates the application of VSLs for control of upstream traffic as a proposed traffic control strategy on the GAR. The objective was to investigate how dynamic VSL and signal control systems could be used in an integrated approach to traffic management to improve the traffic efficiency, safety, and mobility of a congested urban arterial road. The research indicates that the application of VSL could improve the traffic performance and safety during the peak period. It helped to maintain a planned continuous flow through coordinated intersections to avoid congestion. Integrating VSL with other traffic congestion management (changing the signal timings for the congested traffic) appeared effective in improving traffic conditions and reducing total travel time on the GAR. The research highlighted some important elements that could be used for the design and implementation of VSL systems using intelligent transport systems

Metadiscourse in the Academic Writing of EFL and ESL Arabic-Speaking Iraqi Graduate Students

Metadiscourse is a universal rhetorical aspect of languages embodying the notion that the purpose of writing is not only informative; rather, it is a social act enhancing a writer-reader interaction and building effective communicative relationships, thereby creating a reader-friendly text. This thesis examines metadiscourse in L2 academic writing of Arabic-speaking advanced English learners. It investigates the effect of different environments, English as a foreign language (EFL) versus English as a second language (ESL), as well as the effect of time in the development of writers’ metadiscourse. Results were mixed. Quantitatively, the EFL group was closer to the Control group of native speakers in their overall metadiscourse, but the ESL group was closer to the Control group in more than half of the subcategories. Qualitatively, the ESL group was closer to the Control group in four categories, which helped them to establish their ethos and logos. However, both EFL and ESL writers failed to employ other metadiscourse markers to express their attitudes clearly and engage their readers. To bridge the rhetorical gaps in L2 writing, this thesis asserts that explicit instruction in the rhetorical features of English academic writing is not only needed, but also should be required at early stages of writing instruction. Practices, such as identifying metadiscourse markers and their functions in well-written texts, were reported as effective by the case study group in raising their awareness of how metadiscourse can serve the rhetorical functions

COVID-19: An Overview of Current progress and prospects in the frantic race to develop upcoming safe and effective SARS-CoV-2 vaccine Candidates

Coronavirus disease 2019 (COVID-19) is an emerging infectious disease caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). It quickly spread around the world after its first emergence in Wuhan in December 2019 to become a global pandemic with millions of infections worldwide. As of 1 November 2020, nearly 46 million cases have been reported globally and 1.2 million patients succumbed to the viral disease. Due to the lack of efficient and specific therapeutic and prophylactic options available and the need to contain the epidemic, and its economic, political, cultural, demographic and societal consequences, there is a strong consensus globally only the development of a safe and effective vaccine against COVID-19 is the best way to control and ultimately end the pandemic. Faced with the urgency imposed by the speed of expansion of covid-19, scientists are led to launch themselves into a race against the clock to produce a safe and effective coronavirus vaccine by next year. Once the vaccine has been developed, strong international coordination and cooperation between all stakeholders in the vaccine productionprocess will be needed to ensure equitable availability of the vaccine to the global population

Time Domain Traveling Wave Model of Distributed Feedback semiconductor laser with weak optical feedback

International audienceThe Distributed feedback (DFB) semiconductor lasers are widely used in coherent, high speed, long distance optical communications systems due to their attractive properties such as wavelength stability and narrow spectral width. In such systems, external optical feedback happens when a small fraction of the laser output re-enters into the laser cavity from an optical component such as the edge of optical fiber. It is well-established that laser operation could be affected negatively by a small amount of optical feedback. Never theless, semiconductor lasers with optical feed back generate a chaotic output which has been used for many important practical applications like secure communication systems and random number generation. Recently, laser designer emphasis on designing semiconductor lasers with high tolerance to optical feedback

The Contribution of CSR to the Global Performance of Companies: Caseof Moroccan companies with a CSR label

In order to ensure a sustainable development of their structures, the leaders of Moroccan companies are now aware of the need to take into account in their strategic policies new concepts that can meet the expectations of different stakeholders (consumers, employees, government, NGOs,) Based on the assumption that sustainable development and sustainability of companies are closely linked to CSR. The benefits of CSR are not limited to the financial and economic component,but they also involve a renewal of thinking on the objectives and operation of the company Morocco has been undergoing profound economic, social and environmental changes for several years now. Moreover, CSR has gradually become an important theme of globalization, which explains why, despite its voluntary and non-compulsory nature, companies are obliged to adhere to it, but the power to engage in CSR actions depends on the top management and governance bodies of the company. This is why, we have witnessed in recent years a strengthening of governance mechanisms, particularly at the legislative level and the rules of "good governance" enacted or proposed by various regulatory or professional bodies suchas the OECD. A question arising from the commitment of companies in terms of CSR has taken on a crucial importance: the impact of CSR on the performance of companies and we seek to answer the relationship between CSR and corporate governance and the relationship between governance and performance

Synthesis and Characterization of copper oxide(II) nanoparticles prepared by hydrothermal process

تم استخدام طريقة الهدرجة الحرارية لتحضير جسيمات اوكسيد النحاس النانوية , يمكن تحضير جسيمات النحاس النانوية بدون استخدام المذيبات العضوية او مواد غالية الثمن بأستخدام الهدرجة الحرارية. حيود الاشعة السينية أكد بان جسيمات النحاس النانوية ذات تركيب احادي الميل , مع حجم حبيبي 20nm , كما ان التحليل بأستخدام مجهر القوة الذرية اوضح بأن قطر الحجم الحبيبي هو في ضمن المدى النانوي . التحليل بواسطة طيف ( FTIR )اكدت لنا بأن التركيب هو اوكسيد النحاس كما ان خصائص نمط الاهتزاز لأوكسجين-  نحاس تم تأكيده. تم دراسة الخواص البصرية بأستخدام الطيف المرئي للاشعة فوق البنفسجية والتي اوضحت بأن جسيمات النحاس تمتلك انحراف بأتجاه المنطقة المسماة (blue shift) , حيث تمتلك فجوة عالية طاقة (  (4.9eV, وان هذا ربما يعود الى تأثير الحصر الكمي لجسيمات اوكسيد النحاس النانوية.Hydrothermal process was  used to prepare CuO nanoparticles. CuO nanoparticles can be prepare without organic solvents, expensive raw materials by a hydrothermal method. XRD diffraction reveals that CuO nanoparticles have a monoclinic structure with particle size 20nm ,  and AFM analysis showed that the diameter of the Grain size is in a nanometer range. The analysis by FTIR spectra assure that the composition was CuO, and the  features of vibrational types of Cu–O were fixed. also the optical properties was analysed with UV–vis showed that  CuO nano particles have considerable a blue shift  , which have aband gab equal to (4.9 eV ) , and this is because the effect of quntum confienment of prepared CuO nano particles

Synthesis and Characterization of copper oxide(II) nanoparticles prepared by hydrothermal process

تم استخدام طريقة الهدرجة الحرارية لتحضير جسيمات اوكسيد النحاس النانوية , يمكن تحضير جسيمات النحاس النانوية بدون استخدام المذيبات العضوية او مواد غالية الثمن بأستخدام الهدرجة الحرارية. حيود الاشعة السينية أكد بان جسيمات النحاس النانوية ذات تركيب احادي الميل , مع حجم حبيبي 20nm , كما ان التحليل بأستخدام مجهر القوة الذرية اوضح بأن قطر الحجم الحبيبي هو في ضمن المدى النانوي . التحليل بواسطة طيف ( FTIR )اكدت لنا بأن التركيب هو اوكسيد النحاس كما ان خصائص نمط الاهتزاز لأوكسجين-  نحاس تم تأكيده. تم دراسة الخواص البصرية بأستخدام الطيف المرئي للاشعة فوق البنفسجية والتي اوضحت بأن جسيمات النحاس تمتلك انحراف بأتجاه المنطقة المسماة (blue shift) , حيث تمتلك فجوة عالية طاقة (  (4.9eV, وان هذا ربما يعود الى تأثير الحصر الكمي لجسيمات اوكسيد النحاس النانوية.     Hydrothermal process was  used to prepare CuO nanoparticles. CuO nanoparticles can be prepare without organic solvents, expensive raw materials by a hydrothermal method. XRD diffraction reveals that CuO nanoparticles have a monoclinic structure with particle size 20nm ,  and AFM analysis showed that the diameter of the Grain size is in a nanometer range. The analysis by FTIR spectra assure that the composition was CuO, and the  features of vibrational types of Cu–O were fixed. also the optical properties was analysed with UV–vis showed that  CuO nano particles have considerable a blue shift  , which have aband gab equal to (4.9 eV ) , and this is because the effect of quntum confienment of prepared CuO nano particles

Streptomyces Secondary Metabolites

Actinobacteria are found spread widely in nature and particular attention is given to their role in the production of various bioactive secondary metabolites. Tests on soil samples show that there can be a diversity of actinomycetes depending on the climate, the area it is growing in, how dry the soil is, and the quality of the soil. However, it was agreed after tests in Yunnan, China, that the genus Streptomyces sp. is most important in ecological function, representing up to 90% of all soil actinomycetes, and therefore helping to show the important characteristics needed of the soil actinomycete population. Streptomycete compounds are used for other biological activities, not just for antibiotics. It has been found that metabolites can be broadly divided into four classes: (1) regulatory activities in compounds, these include consideration of growth factors, morphogenic agents and siderophores, and plants promoting rhizobia; (2) antagonistic agents, these include antiprotozoans, antibacterials, antifungals, as well as antivirals; (3) agrobiologicals, these include insecticides, pesticides, and herbicides; and (4) pharmacological agents, these include neurological agents, immunomodulators, antitumorals, and enzyme inhibitors. It is found that Streptomyces hygroscopicus is one of the very best examples because it secretes in excess of 180 secondary metabolites to locate simultaneous bioactivities for a given compound. Increasingly, both its agricultural and pharmacological screenings are being used in conjunction with antimicrobial tests and have revealed several unusual aerobiological and therapeutic agents, which were hitherto unknown for biological use as antibiotics. Since streptomycetes are now being used increasingly to screen for antimicrobial activity, reports show the existence of secondary metabolites with other activities that may have been missed. Currently, nearly 17% of biologically active secondary metabolites (nearly 7600 out of 43,000) are known from streptomycetes. It has been found that soil streptomycetes are the main source used by bioactive secondary metabolites. However, recently there have been many and varied types of structurally unique and biologically active secondary metabolites found and obtained from marine actinomycetes, including those from the genus Streptomyces. Also, compounds that are synthesized by streptomycetes exhibit extreme chemical diversity. Diverse form made from from simple amino acid derivatives to high molecular weight proteides, and macrolactones from simple eight membered lactones to different condensed macrolactones. Berdy (1974) introduced the first classification scheme for antibiotics referring to the chemical structure. On the basis of Berdy’s scheme, (1996) recognized that both low and high molecular weight compounds from 63 different chemical classes are produced by streptomycetes