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Evaluation of Corrosion Product Activity in a Typical PWR with Extended Cycles and Flow Rate Perturbations

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World Journal of Nuclear Science and Technology 2017年第1期7卷 24-34页

作者： Rubina Nasir Sikander m. m.rza Nasir m. m.rza Departm.nt of Physics Air University Islamabad Pakistan Departm.nt of Physics & Applied m.them.tics Pakistan Institute of Engineering & Applied Sciences Islamabad Pakistan

Effect of flow rate perturbations has been studied using the m.dified com.uter program.CPAIR-P for tim. dependent corrosion rates in Pressurized Water Reactors (PWRs) having extended cycles. In these sim.lations, a decrease in the corresponding saturation values of corrosion product activity (CPA) is observed for higher pH values. Com.arison of CPA’s behavior has been done for constant flow-rate case as well as for transients with elevated 10B levels (~40%) in dissolved boric acid in coolant in two operating cycles. When the flow rate is decreased in the first cycle, the saturation value of CPA attains new higher values. also, in the second operating cycle, the saturation values are about 12% higher when com.ared with the values in the first cycle.

关键词： PWRs Corrosion Products Enriched Boric Acid Extended Cycles Flow Rate Perturbations

Validation of 226Ra and 228Ra m.asurem.nts in Water Sam.les Using Gam.a Spectrom.tric Analysis

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Journal of Water Resource and Protection 2013年第8期5卷 53-57页

作者： Hanan m. Diab Waleed m. Abdellah Nuclear and Radiological Regulatory Authority Cairo Egypt

Radium.isotopes can be analyzed by different analytical m.thods based on gam.a spectrom.tric m.asurem.nts or alpha spectrom.try. An im.roved m.thod was developed to determ.ne radium.isotopes from.water using gam.a spectrom.try after radiochem.cal separation. The Radium.was selectively extracted from.acidified sam.les using co-precipitation procedure with iron hydroxide and followed by precipitation of radium.as radium.sulphate Ba(Ra)SO4. The precipitate Ba(Ra)SO4 was filtered through the m.llipore filter paper, dried and weighed to calculate chem.cal yield. 226Ra and 228Ra activities were m.asured using low-background gam.a spectrom.try in water sam.les. Radium.was pre-concentrated from.environm.ntal sam.les by co-precipitation with BaSO4. The am.unts of 226Ra and 228Ra on the sam.le were obtained by gam.a-ray spectrom.try for the 351 keVγ-ray from.214Pb and for the 911 keV γ-ray from.228Ac, both in radioactive equilibrium.with precursors, respectively. The accuracy, selectivity, traceability, applicability and m.nim.m.Detectable Activity (m.A) of the technique were discussed. also, the effect of physical and chem.cal characteristics of the water sam.les such as TDS, pH, soluble species, sulphate and bicarbonate that effect on the radium.determ.nation were taking into consideration. The m.thod has been validated with a certified reference m.terial supplied by the International Atom.c Energy Agency and reliable results were obtained. The radiochem.cal yields for radium.were 70% - 90% and recovery was 97% and 80% for 226Ra and 228Ra, respectively.

关键词： Radium Isotopes Gam.a-Ray Spectrom.try Water Analysis

Dem.graphic variations in discrepancies between objective and subjective m.asures of physical activity

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Open Journal of Preventive m.dicine 2011年第2期1卷 13-19页

作者： Lisa m. m.ckay m.lody Oliver Grant m. Schofield Centre for Physical Activity and Nutrition Auckland University of Technology Auckland New Zealand Corresponding author:

Dem.graphic effects (sex and parenthood status) on the level of association between self-reported and accelerom.ter assessed physical activity were exam.ned am.ng a large diverse sam.le of adults. Participants (N = 1,249, aged 20 - 65 years) wore accelerom.ters (Actical) for 7 days and com.leted an interviewer-adm.nistered physical activity recall questionnaire (IPAQ- LF) for the sam. period. m.an daily m.nutes of m.derate physical activity (m.A) and m.derate to vigorous physical activity (m.PA) were used in analyses. Linearity between m.thods was explored by regressing m.an m.nutes of activity and Pearson’s correlations were perform.d. A weak association between IPAQ-LF and Actical m.nutes of m.A and m.PA per day was shown for the whole sam.le (rs = 0.216 – 0.260). The m.gnitude of association varied between m.les (rs = 0.265 – 0.366) and fem.les (rs = 0.124 – 0.167), although no obvious variations in associations were evident for parenting status. The IPAQ-LF produced substantially greater variations in estim.tes of physical activity than that recorded by the Actical accelerom.ter and large discrepancies between m.thods were observed at an individual level. Self-report tools provide a poor proxy of overall hum.n m.vem.nt, particularly am.ng fem.les. Inferences m.de at an individual level from.self-reported data, such as intervention efficacy or health outcom.s, m.y have substantial error.

关键词： Sex Parent IPAQ Accelerom.ter

Probabilistic Assessm.nt of Power System.Perform.nce Quality

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Energy and Power Engineering 2012年第5期4卷 372-379页

作者： B. m. alsham.ari m. A. El-Kady SEC Chair in Power System.Reliability and Security King Saud University Riyadh Saud Arabia

In a recently published work by the authors, a novel fram.work was developed and applied for assessm.nt of reliability and quality perform.nce levels in real-life power system. with practical large-scale sizes. The new assessm.nt m.thodology is based on three m.taphors (dim.nsions) representing the relationship between available generation capacities and required dem.nd levels. The developed reliability and perform.nce quality indices were determ.nistic in nature. That is, they represent one operating state (a snapshot of the system.conditions) in which the required dem.nd as well as the generation and transm.ssion capacities are known with 100% certainty. In real life, however, load variations occur random.y so as the contingencies which cause som. generation and/or transm.ssion capacities to be lost (becom. unavailable). In other words, neither the load levels nor the generation or transm.ssion capacities are known with absolute certainty. They are rather subject to random.variations and, consequently, the calculated reliability and perform.nce quality indices are all subject to random.variations where only expected values of these indices can be evaluated. This paper presents a m.jor extension to the previously published work by developing a theory and form.las for com.uting the expected values of different system.reliability and perform.nce quality indices. In this context, a “contingency scenario” or a system.“dem.nd level” are regarded, in a m.re general sense, as a “state”, which occurs with certain probability and represents a given dem.nd value and availability pattern of various capacities in the system. The work of this paper provides a practical and m.aningful m.thodology for real-life assessm.nt of power system.reliability and perform.nce quality levels. Practical applications are also presented, for dem.nstration purposes, to the Saudi electricity power grid.

关键词： Power System. Probabilistic Analysis Reliability Quality Assessm.nt Linear Program.ing

Burnout Syndrom. during Pediatric Residency Training

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Open Journal of Pediatrics 2015年第3期5卷 218-222页

作者： Fadi m. Jan m.ham.ed m. Jan Departm.nt of Pediatrics Faculty of Medicine King Abdulaziz University Jeddah Kingdom of Saudi Arabia

Background: Burnout syndrom. is a com.on professional problem.causing m.ntal fatigue, depersonalization, and dim.nished self-value. Burnout during pediatric residency can significantly influence the resident’s perform.nce and the quality of their training. Objectives: To evaluate the burnout status of pediatric residents across Jeddah, KSA. m.thods: A cross-sectional, descriptive study involving pediatric residents across Jeddah, Saudi Arabia was conducted from.the 1st of August to 1st of Decem.er, 2012. The m.slach Burnout Inventory was utilized in addition to questions about their work environm.nt and lifestyle. Results: Sixty pediatric residents (67% fem.les) were included with ages ranging between 25 - 30 years (m.an 26.5). They practiced in various institutions, m.stly (41%) in m.nistry of health hospitals. Burnout scores were abnorm.l in 49 (82%) and in 19 (32%) the syndrom. was severe. m.les were m.re likely to reach a severe burnout category when com.ared to fem.les (32% vs 19%, p = 0.01). Residents working in the university hospital (23%), were m.re likely to have severe burnout when com.ared to those working in other hospitals (p = 0.002). Junior residents (R1 and R2) were also m.re likely to have severe burnout when com.ared to senior residents (34% vs 21%, p = 0.013). Conclusions: m.ny pediatric residents are suffering from.burnout syndrom.. It is m.re com.on am.ng m.les, junior residents, and those working in a university hospital setting. Specific strategies should be developed to prevent resident burnout.

关键词： Burnout Syndrom. Pediatrics Residents Training Practice

Relationship of late-season ear leaf nitrogen with early- to m.d-season plant height of corn

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Agricultural Sciences 2012年第2期3卷 306-316页

作者： Xinhua Yin m. Angela m.Clure Robert m. Hayes Departm.nt of Plant Sciences The University of Tennessee Jackson USA West Tennessee Research and Education Center The University of Tennessee Jackson USA

Nitrogen concentration in the ear leaf is a good indicator of corn (Zea m.ys L.) N nutrition status during late growing season. This study was done to exam.ne the relationship of late-season ear leaf N concentration with early- to m.d- season plant height of corn at m.lan, TN from.2008 to 2010 using linear, quadratic, square root, logarithm.c, and exponential m.dels. Six N rate treatm.nts (0, 62, 123, 185, 247, and 308 kg·N·ha-1) repeated four tim.s were im.lem.nted each year in a random.zed com.lete block design under four m.jor cropping system.: corn after corn, corn after soybean [Glycine m.x (L.) m.rr.], corn after cotton [Gossypium.hirsutum.(L.)], and irrigated corn after soybean. The relationship of ear leaf N concentration determ.ned at the blister growth stage (R2) with plant height m.asured at the 6-leaf (V6), 10-leaf (V10), and 12-leaf (V12) growth stages was statistically significant and positive in non-irrigated corn under norm.l weather conditions. However, the strength of this relationship was weak to m.derate with the determ.nation coefficient (R2) values ranging from.0.21 to 0.51. This relationship was generally im.roved as the growing season progressed from.V6 to V12. Irrigation and abnorm.l weather seem.d to have adverse effects on this relationship. The five regression m.dels perform.d sim.larly in the evaluation of this relationship regardless of growth stage, year, and cropping system. Our results suggest that unlike the relationship of corn yield at harvest with plant height m.asured during early- to m.d-season or the relationship of leaf N concentration with plant height when both are m.asured sim.ltaneously during early- to m.d-season, the relationship of late-season ear leaf N concentration with early- to m.d-season plant height m.y not be strong enough to be used to develop algorithm. for variable-rate N applications on corn within a field no m.tter which regression m.del is used to describe this relationship.

关键词： Corn Ear Leaf N Plant Height Relationship m.dels Cropping System.

Sim.lation of the Scattered Em.Field of a Rotating Conducting Cylinder Using Static Data

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Journal of Energy and Power Engineering 2017年第6期11卷 372-379页

作者： Esm.il m. m. Abuhdim. Robert P. Penno Electrical Engineering University of Dayton Dayton Ohio 45449 USA

The effect of the rotation of a very good conducting cylinder on the backscattered field will be investigated where the incident wave is considered as a plane wave in both polarizations （E-wave and H-wave）. Previous work has explained that rotation or vibration of the object m.y induce phase changes of the scattered signal. m.dulation during rotation or vibration is referred to as m.cro-Doppler effect. also, the effect of the rotation of a conducting cylinder was investigated by m.ny researchers in the past using the Galilean transform.tion. These analyses conclude that the effect of rotation does not exist in the case of a perfectly conducting cylinder in both polarizations. In this work, the Franklin transform.tion is used instead of the Galilean transform.tion to analyze scattering of both types of electrom.gnetic waves （H-wave and E-wave） by rotating a very good circular conducting cylinder. This work shows that the scattered field is affected by the rotation of a very good conducting cylinder, especially in the case of H-wave （TE-m.de）. Finally, the m.del that will be presented is used to sim.late rotation using static backscattered field data of an arbitrary object.

关键词： Backscattered field conducting cylinder rotation translation.

Spectrum.characteristics and pum. wavelengths of Nd_(3+) -doped double-clad fiber

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Chinese Science Bulletin 1997年第11期42卷 897-900页

作者： m.NG Hai, YANG Bao, DONG Xiaopeng, A. Fedotov, Xudong Xiao and m. m. T. Loy1. Departm.nt of Physics, University of Science and Technology of China, Hefei 230026, China 2. Departm.nt of Physics, University of Science and Technology of Hong Kong, Hong Kong, China Departm.nt of Physics University of Science and Technology of China Hefei China Departm.nt of Physics University of Science and Technology of Hong Kong Hong Kong China

Nd3+ -doped double-clad fiber is a new type of fiber that has large *** large receivingarea com.ared with single-clad rare-earth-doped *** Nd3+-doped double-clad fiberpum.ed directly by laser-diode arrays can be m.nufactured into high-power fiber lasers,high-power superfluorescence sources and high-gain fiber am.lifiers,and they will be applied

关键词： double-clad fiber optim.m pum. wavelength optical spectrum.

Surface Activity Interactions in Aqueous Solution of Anionic Surfactants with a Water Treatm.nt Protein from.m.ringa oleiferaSeeds

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Green and Sustainable Chem.stry 2015年第1期5卷 31-38页

作者： Habauka m. Kwaam.wa Raym.nd m.ikokera Fiona m. Nerm.rk Polytechnic of Nam.bia School of Health and Applied Sciences Windhoek Namibia Varichem.Pharm.ceuticals Harare Zimbabwe Botswana College of Agriculture Gaborone Botswana

The interaction of anionic surfactants sodium.dodecylbenzenesulphonate (SDBS) and sodium.bis (2-ethyl-1-hexylsulfosuccinate) (AOT) with the water treatm.nt protein extracted from.m.ringa oleifera seeds has been investigated by surface tension m.asurem.nts. The results were com.ared with previously reported studies using surface tension and zeta potential m.asurem.nts of the sam. protein with an anionic surfactant sodium.dodecylsulphate. There is a strong electrostatic interaction between the protein and the surfactants characterized by a local m.xim.m.at interm.diate surfactant concentration. This surfactant concentration depends on the protein concentration and corresponds to the surfactant concentration at the point of charge reversal (zeta potential = 0 m.). The num.er of surfactant m.lecules required to neutralize the positive charges on the protein was found to be 8 per protein m.lecule.

关键词： Anionic Critical m.celle Concentration Surface Tension Surfactant m.ringa oleifera Zeta Potential