97,887 research outputs found
Mrs. G. C. Berg and daughter, Connie Lu, left, with Mrs. R. M. Humphreys and daughter, Sue Lynn Humphreys
No full textMrs. G. C. Berg and daughter, Connie Lu, left, with Mrs. R. M. Humphreys and daughter, Sue Lynn.https://mavmatrix.uta.edu/specialcollections_startelegram1940s/12936/thumbnail.jp
Mobile Exam System – MES: Architecture for Database Management
No full textAs the mobile applications are constantly facing a rapid development in the recent years especially in the academic environment such as student response system (Lópeza, Royoa, Labordab & Calvoa, 2009; Ngai & Gunasekaran, 2007; Mary & Biju, 2008; Nayak & Erinjeri, 2008; Roth, Ivanchenko & Record, 2008; Lu, Stav & Pain, 2009; Lu, 2009; Turning technologies, 2010) used in universities and other educational institutions; there has not been reported an effective and scalable Database Management System to support fast and reliable data storage and retrieval. This paper presents Database Management Architecture for an Innovative Evaluation System based on Mobile Learning Applications. The need for a relatively stable, independent and extensible data model for faster data storage and retrieval is analyzed and investigated. It concludes by emphasizing further investigation for high throughput so as to support multimedia data such as video clips, images and documents
Solid phase extraction-based separation of the nuclear isomers <sup>177m</sup>Lu and <sup>177</sup>Lu
No full textA solid phase extraction based 177mLu-177Lu separation method has been investigated for its feasibility to be used in the radionuclide generator. The use of 2,2′,2”-(10-(2,6-dioxotetrahydro-2H-pyran-3-yl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetic acid, (DOTAGA-anhydride) allowed grafting of DOTA (1,4,7,10-tetraazacyclododecane N,N′,N″,N‴-tetraacetic acid) complex on the surface of commercially available amino propyl silica. The grafting of DOTA has been confirmed by several characterization techniques. The thermogravimetric analysis reveals that the 0.33 mmol DOTA groups have been grafted per gram of silica. However, during the Lu ion complexation, a 10 times lower Lu adsorption capacity of 0.03 mmol g−1 could be achieved under the studied reaction conditions. The results indicate that the grafting of DOTA on solid affects the Lu coordination and also influences the kinetics of Lu-DOTA complexation. The weak coordination resulted in high 177mLu leakage, while the unreacted DOTA groups interfer with the 177Lu release. This is evident from the 0.3% 177mLu leakage combined with a177Lu extraction efficiency of 25%. Overall, the results show a177mLu-177Lu separation with a maximum 177Lu/177mLu activity ratio of 25. But this is still far away from clinically acceptable activity ratio of 10,000 for which future work is recommended.RST/Applied Radiation & Isotope
Modelling of the <sup>177m</sup>Lu/<sup>177</sup>Lu radionuclide generator
No full textIn order to determine the potential of 177mLu/177Lu radionuclide generator in 177Lu production it is important to establish the technical needs that can lead to a clinically acceptable 177Lu product quality. In this work, a model that includes all the processes and the parameters affecting the performance of the 177mLu/177Lu radionuclide generator has been developed. The model has been based on the use of a ligand to complex 177mLu ions, followed by the separation of the freed 177Lu ions. The dissociation kinetics of the Lu-ligand complex has been found to be the most crucial aspect governing the specific activity and 177mLu content of the produced 177Lu. The dissociation rate constants lower than 1*10-11 s-1 would be required to lead to onsite 177Lu production with specific activity close to theoretical maximum of 4.1 TBq 177Lu/mg Lu and with 177mLu content of less than 0.01%. Lastly, the calculations suggest that more than one patient dose per week can be supplied for a period of up to 7 months on starting with the 177mLu produced using 3 g Lu2O3 target with 60% 176Lu enrichment. The requirements of the starting 177mLu activity production needs to be adapted depending on the required patient doses, and the technical specifications of the involved 177mLu-177Lu separation process.RST/Applied Radiation & IsotopesChemE/Catalysis Engineerin
Low-energy phonon excitations in superconducting RNiB2C (R = Lu, Y)
No full textInelastic neutron-scattering techniques have been used to study the low-energy phonon excitations in superconducting RNi2B2C (R = Lu, Y) to further characterize the anomalous features observed by Kawano et al. [Phys. Rev. Lett. 77, 4628 (1996)] for R = Y and Stassis et al. [Phys. Rev. B 55, R8678 (1997)] for R = Lu, when these systems enter the superconducting ground state. We find that above T, the frequencies of the Delta(4)[xi 00] lowest-lying acoustic and optic phonon modes decrease with decreasing temperature, for xi close to the nesting vector xi(m). In addition there is a shift of intensity from the upper to the lower mode, an effect characteristic of mode coupling. The observed intensity transfer between these modes above T-c can be described satisfactorily in both compounds by a coupled-mode model. Below T-c the observed spectrum changes dramatically: it consists of a sharp peak at approximately 4 meV with a broad weak shoulder at higher energies. The experimental results unambiguously show that this dramatic change is due to the onset of superconductivity in these compounds. In this temperature region, the results are in qualitative agreement with recent theoretical calculations.This article is published as Bullock, M., J. Zarestky, C. Stassis, A. Goldman, P. Canfield, Zentaro Honda, Gen Shirane, and S. M. Shapiro. "Low-energy phonon excitations in superconducting R Ni 2 B 2 C (R= Lu, Y)." Physical Review B 57, no. 13 (1998): 7916.
DOI: 10.1103/PhysRevB.57.7916.
Copyright 1998 American Physical Society.
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Effect of dry-wet cycling on NOx degradation and sterilization properties of cement mortar with g-C3N4/CoAl-LDH
No full textThe influencing mechanism of dry-wet cycling on the NOx degradation and sterilization properties of photocatalytic cement mortar (PCM) with g-C3N4/CoAl-LDH was investigated through the optical properties, mineral composition of cement hydration products, pore characteristics and nitrogen (N) content. The results indicate that as the cycle number increases, the N content, band gap, Urbach energy, NOx degradation rate and sterilization rate exhibit periodic variations, while the peak intensity of CH (a cement hydration product) decreases gradually. After 10 cycles, PCM demonstrates the maximum Urbach energy, N content, NOx degradation and sterilization rate, as well as the minimum band gap. At this stage, the Urbach energy, N content, NOx degradation and sterilization rate of PCM with 1.0 % g-C3N4/CoAl-LDH increase by 16.2 %, 24.9 %, 15.4 % and 40.8 %, while the band gap and the CH peak intensity decrease by 5.4 % and 23.4 %, respectively. Although the NOx degradation and sterilization rates of PCM exhibit periodic fluctuations during the dry-wet cycling, both of them surpass those before the cycles, which shows the excellent photocatalytic durability of PCM. It is expected that this study not only presents a new perspective on evaluating the durability of PCM's photocatalytic property, but also provides an alternative approach for the design of new multifunctional nanocomposites in cementitious materials for environmental pollution control
The dialogue between the author and the hero in the “Notes” of G. R. Derzhavin
No full textВ центре внимания автора статьи «Записки» Г. Р. Державина, представляющие по своей сути его автобиографию. Труд этот был создан на закате жизни, он включает все важнейшие события жизни Г. Р. Державина, поэта и государственного деятеля. Рассказ ведется от третьего лица, что придает особую атмосферу повествованию, выстраивается своеобразный диалог между автором и героем, все это и является предметом исследования автора статьи.The focus of the author of the article “Notes” G. R. Derzhavin, representing in essence his autobiography. This work was created at the end of his life; it includes all the most important events in the life of G. R. Derzhavin, poet and statesman. The story is told in a third person, which gives a special atmosphere to the story, a certain dialogue emerges between the author and the hero, all this is the subject of the author's research
Organik ve konvansiyonel f nd klar n (corylus avellana l.) baz fiziksel özellikleri
No full textSon y llarda bilimsel çal malar nda beslenme-sa l k ili kisi aç k bir ekilde ortaya koyulmu tur. Bunun neticesinde tüketicilerde daha sa l kl g da aray do mu ve bu talebin kar lanmas için organik (ekolojik) tar m ve organik g da uygulamalar ortaya ç km t r. Organik f nd k tar m s n rl üretimin yan nda birçok organik üründe oldu u gibi art e ilimindedir. Bu çal mada organik ve konvansiyonel f nd k üretiminin yap ld Karadeniz Bölgesi'nden (Trabzon, Ordu, Samsun, Düzce) ticari öneme sahip Tombul, Fo a, Sivri, Çak ldak, Mincane ve Palaz çe itlerine ait örnekler üzerinde çe itli pomolojik analizler yap lm t r. Yap lan analizler sonucunda meyve geni li i, iç meyve uzunlu u, iç meyve geni li i, iç meyve kal nl , meyve a rl , iç a rl ve kabuk kal nl de erlerinde konvansiyonel örneklerin daha yüksek de erlere sahip oldu u görülmü tür. Meyve uzunlu u, meyve kal nl , göbek bo lu u, rand man, sa lam iç oran ve kusurlu iç oranlar nda uygulamalar aras nda fark tespit edilmemi tir.In recent years, the relationship between nutrition and health has been clearly presented in the light of scientific studies. Recently, consumers have been demanding for healthier foods; therefore, organic (ecological) agriculture and organic food applications have emerged to meet this demand. Organic hazelnut production has limited and its agriculture tends to increase gradually in recent years. In this study, various pomological analyses were carried out on samples belonging to Tombul, Fo a, Sivri, çak ldak, Mincane and Palaz varieties of commercial importance grown in the Black Sea Region of Turkey (Trabzon, Ordu, Samsun and Düzce cities) where organic and conventional hazelnut production was located. Results indicated that conventional samples had higher values in terms of nut width, kernel length, kernel width, kernel thickness, nut weight, kernel weight and shell thickness values. There was no difference in nut length, nut thickness, internal cavity, kernel percentage, good kernels and the rate of defected kernel between two types of hazelnuts
Raman modes of RNi(2)B(2)C (R=Lu,Ho,Y) single crystals
No full textResults of Raman measurements on RNi(2)B(2)C (R=Lu, Ho, Y) single crystals are reported. Raman peaks are observed at 190 cm(-1) and near 830 cm(-1). From the polarization-dependence measurements, these peaks are assigned to be the Ni-B-1g and the B-A(1g) modes, respectively. Raman study on the effects of boron isotope B-10 substitution for B-11 in the LuNi2B2C crystals confirms that the mode near 830 cm(-1) is due to the vibration of B atoms. However, from these single crystals, the expected Ni-E(g) and B-E(g) modes are not observed.This article is published as Park, Hyun-Jung, Hye-Soo Shin, Hye-Gyong Lee, In-Sang Yang, W. C. Lee, B. K. Cho, P. C. Canfield, and D. C. Johnston. "Raman modes of R Ni 2 B 2 C (R= Lu, Ho, Y) single crystals." Physical Review B 53, no. 5 (1996): 2237.
DOI: 10.1103/PhysRevB.53.2237.
Copyright 1996 American Physical Society.
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Electron spin resonance of Gd3+ in the normal state of RNi2B2C (R=Y,Lu)
No full textElectron spin resonance (ESR) of Gd3+ in the normal state (T>T-c) of R1-xGdxNi2B2C (R=Y,Lu) is reported. The results show that the exchange coupling between the rare-earth localized magnetic moment and the conduction electrons depends on the conduction electrons momentum transfer (\k(F)(in)-k(F)(out)\ = q), i.e., J(fs)(q). The temperature dependence of the ESR linewidth yields a value for one of the exchange parameters, [J(fs)(2)(q)](EF)(1/2), which is in agreement with that estimated from the slope of the initial linear decrease of T-c by the Gd3+ impurities. These results indicate that the R1-xGdxNi2B2C (R=Y,Lu) compounds behave as conventional BCS superconductors, in agreement with previous reports.This article is published as Pagliuso, P. G., C. Rettori, S. B. Oseroff, P. C. Canfield, E. M. Baggio-Saitovitch, and D. Sanchez. "Electron spin resonance of Gd 3+ in the normal state of R Ni 2 B 2 C (R= Y, L u)." Physical Review B 57, no. 6 (1998): 3668.
DOI: 10.1103/PhysRevB.57.3668.
Copyright 1998 American Physical Society.
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