Study of Nuclear Structure Parameters by Using the (n_th, 2\gamma) Reaction

N. Jovančević,L. V. Mitsyna,A. M. Sukhovoj,D. Knežević,M. Krmar,J. Petrović,S. Oberstedt,A. Dragić,F.-J. Hambsch,V. D. Cong 한국물리학회 2019 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.75 No.2

The empirical Dubna model for investigating of the cascade gamma-decay of the neutron resonance allows a simultaneous determination of the level density and radiative strengths in a region up to the binding neutron energy for any nucleus. Data can be obtained by determining the intensities of two-step cascades between a decaying compound-state and a group of low-lying levels of the nucleus and describing these intensities by using the most appropriate models prescribed parametrically. For evaluation and minimization of systematical errors of the models used for the level density and radiative strengths for primary gamma transitions spectroscopic information about quanta sequence for observed resolved cascades must be obtained and at least two different sets of models must be used for verification of derivable nuclear parameters. The step-wise structure, which was observed in the energy dependence of the level density for more than 40 investigated nuclei, shows that the structure of a nucleus modifies by excitation.

Studies of N-Doped p-ZnO Layers Grown on c-Sapphire by Radical Source Molecular Beam Epitaxy

S. V. Ivanov,A. El-Shaer,M. Al-Suleiman,A. Bakin,A. Waag,O. G. Lyublinskaya,N. M. Shmidt,S. B. Listoshin,R. N. Kyutt,V. V. Ratnikov,A. Ya. Terentyev,B. Ya. Ber,T. A. Komissarova,L. I. Ryabova,D. R. Kh 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.53 No.5

We report on the fabrication of p-type ZnO:N layers using radical-source molecular beam epitaxy and post-growth annealing of the samples. Plasma-activated oxygen and nitrogen fluxes are supplied via a single plasma cell. The combination of low growth temperature (350 − 400 ℃), slightly O-rich conditions, and post-growth annealing in the range of 650 − 800 ℃ results in efficient nitrogen pdoping with Hall hole concentration 3 × 1017 cm−3. The details of the structural and the electrical characterizations of the films are discussed. We report on the fabrication of p-type ZnO:N layers using radical-source molecular beam epitaxy and post-growth annealing of the samples. Plasma-activated oxygen and nitrogen fluxes are supplied via a single plasma cell. The combination of low growth temperature (350 − 400 ℃), slightly O-rich conditions, and post-growth annealing in the range of 650 − 800 ℃ results in efficient nitrogen pdoping with Hall hole concentration 3 × 1017 cm−3. The details of the structural and the electrical characterizations of the films are discussed.

Effect of feeding of blend of essential oils on methane production, growth, and nutrient utilization in growing buffaloes

Yatoo, M.A.,Chaudhary, L.C.,Agarwal, N.,Chaturvedi, V.B.,Kamra, D.N. Asian Australasian Association of Animal Productio 2018 Animal Bioscience Vol.31 No.5

Objective: An experiment was conducted to study the effect of a blend of essential oils (BEO) on enteric methane emission and growth performance of buffaloes (Bubalus bubalis). Methods: Twenty one growing male buffaloes (average body weight of $279{\pm}9.3kg$) were divided in to three groups. The animals of all the three groups were fed on a ration consisting of wheat straw and concentrate mixture targeting 500 g daily live weight gain. The three dietary groups were; Group 1, control without additive; Group 2 and 3, supplemented with BEO at 0.15 and 0.30 mL/kg of dry matter intake (DMI), respectively. Results: During six months feeding trial, the intake and digestibility of dry matter and nutrients (organic matter, crude protein, ether extract, neutral detergent fibre, and acid detergent fibre) were similar in all the groups. The average body weight gain was tended to improve (p = 0.084) in Group 2 and Group 3 as compared to control animals. Feeding of BEO did not affect feed conversion efficiency of the animals. The calves of all the three groups were in positive nitrogen balance with no difference in nitrogen metabolism. During respiration chamber studies the methane production (L/kg DMI and L/kg digestible dry matter intake was significantly (p<0.001) lower in Group 2 and Group 3 as compared to control animals. Conclusion: The results indicated that the BEO tested in the present study have shown potential to reduce enteric methane production without compromising the nutrient utilization and animal performance and could be further explored for its use as feed additive to mitigate enteric methane production in livestock.

Rapid Variable-Number Tandem-Repeat Genotyping for Mycobacterium leprae Clinical Specimens

Kimura, M.,Sakamuri, R. M.,Groathouse, N. A.,Rivoire, B. L.,Gingrich, D.,Krueger-Koplin, S.,Cho, S.-N.,Brennan, P. J.,Vissa, V. American Society for Microbiology 2009 Journal of clinical microbiology Vol.47 No.6

<P>Mycobacterium leprae is the noncultivable pathogen of leprosy. Since the genome sequence of an isolate of M. leprae has become available, multiple-locus variable-number tandem-repeat (VNTR) analysis (MLVA) has been explored as a tool for strain typing and identification of chains of transmission of leprosy. In order to discover VNTRs and develop methods transferable to clinical samples, MLVA was applied to a global collection of M. leprae isolates derived from leprosy patients and propagated in armadillo hosts. PCR amplification, agarose gel electrophoresis, and sequencing methods were applied to DNA extracts from these infected armadillo tissues (n = 21). We identified polymorphisms in 15 out of 25 short-tandem-repeat (STR) loci previously selected by in silico analyses of the M. leprae genome. We then developed multiplex PCR for amplification of these 15 loci in four separate PCRs suitable for fluorescent fragment length analysis and demonstrated STR profiles highly concordant with those from the sequencing methods. Subsequently, we extended this method to DNA extracts from human clinical specimens, such as skin biopsy specimens (n = 30). With these techniques, mapping of multiple loci and differentiation of genotypes have been possible using total DNA extracts from limited amounts of clinical samples at a reduced cost and with less time. These practical methods are therefore available and applicable to answer focused epidemiological questions and to allow monitoring of the transmission of M. leprae in different countries where leprosy is endemic.</P>

Topical Anti-Inflammatory Activity of a Monofloral Honey of Mimosa scabrella Provided by Melipona marginata During Winter in Southern Brazil

Débora M.Borsato,Arthur S. Prudente,Patrícia M. Döll-Boscardin,Aurélio V. Borsato,Cynthia F.P. Luz,Beatriz H.L.N.S. Maia,Daniela A. Cabrini,Michel F. Otuki,Marilis D. Miguel,Paulo V. Farago,Obdulio G. 한국식품영양과학회 2014 Journal of medicinal food Vol.17 No.7

Melipona marginata is an endangered species of stingless bee from Brazil that produces honey with particular physicochemical features and a remarkable exotic flavor. To the best of our knowledge, this is the first report devoted to exploring the medicinal potential of this honey. Thus, the aim of this paper was to investigate the potential anti-inflammatory activity of honey extract from M. marginata on skin inflammation. The honey sample was classified as a monofloral honey of Mimosa scabrella. The presence of 11 phenolic compounds as kaempferol and caffeic acid was detected using the highperformance liquid chromatography-electrospray ionization-tandem mass spectrometry (HPLC-UV-ESI-MS) method. The anti-inflammatory activity was measured using a 12-O-tetradecanoylphorbol-13-acetate-induced ear edema model of inflammation in mice. The topical application of the M. marginata honey extract (1.0 mg/ear) was able to reduce ear edema with an inhibitory effect of 54 – 5%. This extract decreased the myeloperoxidase activity in 75 – 3%, which suggests a lower leucocyte infiltration that was confirmed by histological analysis. This extract also provided a reduction of 55 – 14% in the production of reactive oxygen species. This anti-inflammatory activity could be due to a synergic effect of the phenolic compounds identified in the honey sample. Taken together, these results open up new possibilities for the use of M. marginata honey extract in skin disorders.

Numerical modelling for evaluating the TMD performance in an industrial chimney

A.L. Ibán,A.V. Belver,J.M.W. Brownjohn,P.M. López-Reyes,K. Koo 한국풍공학회 2013 한국풍공학회지 Vol.17 No.3

A numerical technique for fluid-structure interaction, which is based on the finite element method (FEM) and computational fluid dynamics (CFD), was developed for application to an industrial chimney equipped with a pendulum tuned mass damper (TMD). In order to solve the structural problem, a one-dimensional beam model (Navier-Bernoulli) was considered and, for the dynamical problem, the standard second-order Newmark method was used. Navier-Stokes equations for incompressible flow are solved in several horizontal planes to determine the pressure in the boundary of the corresponding cross-section of the chimney. Forces per unit length were obtained by integrating the pressure and are introduced in the structure using standard FEM interpolation techniques. For the fluid problem, a fractional step scheme based on a second order pressure splitting has been used. In each fluid plane, the displacements have been taken into account considering an Arbitrary Lagrangian Eulerian approach. The stabilization of convection and diffusion terms is achieved by means of quasi-static orthogonal subscales. For each period of time, the fluid problem was solved and the geometry of the mesh of each fluid plane is updated according to the structure displacements. Using this technique, along-wind and across-wind effects have been properly explained. The method was applied to an industrial chimney in three scenarios (with or without TMD and for different damping values) and for two wind speeds, showing different responses.

Electrochromic performance of the mixed V₂O₅-WO₃ thin films synthesized by pulsed spray pyrolysis technique

Patil, C.E.,Tarwal, N.L.,Jadhav, P.R.,Shinde, P.S.,Deshmukh, H.P.,Karanjkar, M.M.,Moholkar, A.V.,Gang, M.G.,Kim, J.H.,Patil, P.S. Elsevier 2014 Current Applied Physics Vol.14 No.3

Vanadium pentoxide (V<SUB>2</SUB>O<SUB>5</SUB>) mixed tungsten trioxide (WO<SUB>3</SUB>) thin films have been synthesized by a novel pulsed spray pyrolysis technique (PSPT) on glass and fluorine doped tin oxide (FTO) coated glass substrates at 400 <SUP>o</SUP>C. Aqueous solutions of equimolar vanadium chloride and ammonium tungstate were mixed in volume proportions (5%, 10% and 15%) for the deposition of V<SUB>2</SUB>O<SUB>5</SUB>-WO<SUB>3</SUB> thin films. The structural, morphological, optical and electrochemical properties of V<SUB>2</SUB>O<SUB>5</SUB>-WO<SUB>3</SUB> thin films were investigated by FT-IR, XRD, SEM, cyclic voltammetry, chronoamperometry and chronocoulometry techniques. The results showed that the electrochemical properties of V<SUB>2</SUB>O<SUB>5</SUB> were altered by mixing WO<SUB>3</SUB>. All the films exhibited cathodic electrochromism in lithium containing electrolyte (0.5 M LiClO<SUB>4</SUB> + propylene carbonate (PC)). Maximum coloration efficiency (CE) of about 49 cm<SUP>2</SUP> C<SUP>-1</SUP> was observed for the V<SUB>2</SUB>O<SUB>5</SUB> film mixed with 15% WO<SUB>3</SUB>. The electrochemical stability of the sample was examined and it was found to be stable up to 1000 cycles.

Synthesis of γ-Al₂O₃ nanopowder by the sol-gel method: Effect of different acid precursors on the superficial, morphological and structural properties

Arquímedes Cruz-López,Odilón Vázquez Cuchillo,Isaías Juárez Ramírez,Lilia M. Bautista-Carrillo,Elvira Zarazua-Morin 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.5

The main aim of this investigation is to study the effect of three acid precursors (nitric acid, acetic acid and citric acid) during the synthesis of γ-Al2O3 nanopowder by the sol-gel method. The TEM analyses showed that the γ-Al2O3 prepared by using the strongest acid were irregular nanofibers with a length of 50 nm and a diameter of 5 nm, while the γ-Al2O3 prepared with citric acid showed agglomerates. On the other hand, the SEM analyses showed very similar morphologies. The N2-physisorption analyses confirmed that there is a relationship between the acidity and the surface area; and between the presence of mesopores and micropores on the surface of the synthesized Al2O3. The effect of the acid strength on the surface area was as follows: nitric acid (347 m2·g−1) > acetic acid (252 m2·g−1) > citric acid (164 m2·g−1). In addition, the XRD results confirmed that for all the samples thermally treated at 600 oC, the main phase was γ-Al2O3; nevertheless, the thermal analyses showed that the γ-Al2O3 synthesized with the weakest acid was not stable above 600 oC. The main aim of this investigation is to study the effect of three acid precursors (nitric acid, acetic acid and citric acid) during the synthesis of γ-Al2O3 nanopowder by the sol-gel method. The TEM analyses showed that the γ-Al2O3 prepared by using the strongest acid were irregular nanofibers with a length of 50 nm and a diameter of 5 nm, while the γ-Al2O3 prepared with citric acid showed agglomerates. On the other hand, the SEM analyses showed very similar morphologies. The N2-physisorption analyses confirmed that there is a relationship between the acidity and the surface area; and between the presence of mesopores and micropores on the surface of the synthesized Al2O3. The effect of the acid strength on the surface area was as follows: nitric acid (347 m2·g−1) > acetic acid (252 m2·g−1) > citric acid (164 m2·g−1). In addition, the XRD results confirmed that for all the samples thermally treated at 600 oC, the main phase was γ-Al2O3; nevertheless, the thermal analyses showed that the γ-Al2O3 synthesized with the weakest acid was not stable above 600 oC.

Electrochromic performance of the mixed V2O5eWO3 thin films synthesized by pulsed spray pyrolysis technique

C.E. Patil,N.L. Tarwal,P.R. Jadhav,P.S. Shinde,H.P. Deshmukh,J.D. Song,A.V. Moholkar,M.G. Gang,김진혁,P.S. Patil 한국물리학회 2014 Current Applied Physics Vol.14 No.3

Vanadium pentoxide (V2O5) mixed tungsten trioxide (WO3) thin films have been synthesized by a novel pulsed spray pyrolysis technique (PSPT) on glass and fluorine doped tin oxide (FTO) coated glass substrates at 400 C. Aqueous solutions of equimolar vanadium chloride and ammonium tungstate were mixed in volume proportions (5%, 10% and 15%) for the deposition of V2O5eWO3 thin films. The structural, morphological, optical and electrochemical properties of V2O5eWO3 thin films were investigated by FT-IR, XRD, SEM, cyclic voltammetry, chronoamperometry and chronocoulometry techniques. The results showed that the electrochemical properties of V2O5 were altered by mixing WO3. All the films exhibited cathodic electrochromism in lithium containing electrolyte (0.5 M LiClO4 þ propylene carbonate (PC)). Maximum coloration efficiency (CE) of about 49 cm2 C1 was observed for the V2O5 film mixed with 15% WO3. The electrochemical stability of the sample was examined and it was found to be stable up to 1000 cycles.

Evaluation of MgCo2O4 nanoparticles as a gas sensor for the detection of acetone in the diabetic and non-diabetic range

J. P. Morán-Lázaro,F. López-Urías,E. Muñoz-Sandoval,M. Courel-Piedrahita,A. Carreon-Alvarez,V. M. Rodríguez-Betancourtt,I. Zamudio-Torres,E. S. Guillén-López,A. Palafox-Corona 대한금속·재료학회 2023 ELECTRONIC MATERIALS LETTERS Vol.19 No.1

The acetone contained in human breath is of great interest for the health sector as it is a marker that allows to diagnoseand control diabetes in a non-invasive way. However, its concentration is extremely low. Therefore, high-performanceacetone sensors are still a challenge. With this in mind, MgCo 2 O 4 nanoparticles were synthesized using a microwaveassistedcolloidal route with subsequent calcination. Structural and morphological characterizations were done through varioustechniques. The MgCo 2 O 4 sensor was fabricated with the sample calcined at 500 °C. The sensing results showed that thesensor could detect acetone vapors ranging from 0.5 to 50 ppm at an optimum operating temperature of 250 °C with a highresponse, repeatability, stability, and selectivity. These sensing characteristics revealed that MgCo 2 O 4 could be used as a newsensor material to detect acetone in exhaled human breath.