Carbon nanotubes

Nanotubes, the last in the focus of scientists in a series of all carbon materials discovered over the last several decades arc the most interesting and have the greatest potential. This review aims at presenting in a concise manner the considerable amount of knowledge accumulated since the discovery of this amazing form of solid carbon, particularly during the last 15 years. The topics include methods of synthesis., mathematical description, characterization by Raman spectroscopy, most important properties and applications. Problems related to the determination of CNT properties, as well as difficulties regarding their applications, in particular scaling, which Would lead to their utilization, are outlined

Present status of the NET IBK computer code package for in-core fuel management and related core parameter calculations

This paper presents and discusses the current status of the NET IBK (Nuclear Engineering Department of the Boris Kidric Institute of Nuclear Sciences) computer code package for nuclear analysis of power reactors and in-core fuel management The standard scheme for reactor fuel burnup analysis comprises the WIMS code and several 2 D (RZ or XY) and 3 D (XYZ) codes for overall reactor core calculations and criticality search They are coupled and modified to compute neutron flux, power density distribution and burnup taking into account spatial variations of temperature and xenon poisoning, as well as the reactivity changes due to xenon transients during the start-up and shut-down Presently, codes for overall reactor calculations are based on finite difference solution of group diffusion equations Efforts are being made to improve reactor cell and fuel assembly parameters calculations, and to develop advanced methods for solving diffusion equations Also, an optimization model, based on coarse zonal discretization of a reactor core is being developed for optimal fuel loading pattern search The NET IBK computer code package has been extensively used to study advanced fuel utilization schemes in different types of power reactors, as well as for solving in-core fuel management problems of the own research reactors Particular attention has been paid to experimental verification of the calculational procedures In this paper, a number of interesting results is presented and discussed 15 refs, 6 figs, 7 tabsINIS record: [http://inis.iaea.org/search/search.aspx?orig_q=RN:22023261

Morfološko i imunocitohemijsko ispitivanje tumorskih ćelija kod Marekove bolesti

In this paper are described the macroscopic, microscopic and immunophenotypic characteristics of tumors in Marek’s disease (MD). Liver, kidneys, lungs, heart, proventriclus, ovary and nerves of sciatic plexus collected from 20 chickens aged 8 to 24 weeks were examined. Lymphoproliferative enlargement in various organs of focal and diffuse character was found. The affected organs were enlarged, compact and very brittle, irregular in shape, grayish-red or grayish-white and of fatty consistency. Most often characteristic changes were in the spleen, liver, proventriculus and ovary that usually had a compact or ribbed, fatty cauliflower like formation, different in size. On histological examination proliferation of small and medium size lymphocytes, lymphoblast cells, Marek’s disease cells and activated reticulum cells were found. Tumor proliferates predominantly consisted of lymphoblasts and had all the characteristics of a lymphoma. Immunohistochemical analysis revealed that lymphoma cells in MD are of CD3 + phenotype. In liver proliferates numerous CD79+ cells were found perivasculary, which is an interesting finding demanding further research.U ovom radu su opisane makroskopske, mikroskopske i imunofenotipske karakteristike tumora kod Marekove bolesti (MB). Ispitivanjem su bili obuhvaćeni jetra, bubreg, pluća, srce, žlezdani želudac, jajnik i nervi ishijadičnog pleksusa dvadeset pilića starosti između8i24 nedelje. U ispitivanom materijalu ustanovljeno je limfoproliferativno bujanje u različitim organima, fokalnog ili difuznog karaktera, pri čemu su zahvaćeni organi znatno povećani, kompaktni i veoma krti, često nepravilnog oblika, sivocrveni ili sivobeli, slaninastog izgleda. Najčešće i najkarakterističnije su bili promenjeni slezina, jetra, žlezdani želudac, jajnici koji obično predstavljaju kompaktne ili izbrazdane tvorevine poput karfiola, slaninastog izgleda i različite veličine. Histološki, u organima se nalaze proliferati malih i srednjih limfocita, zatim limfoblasta, ćelija Marekove bolesti i aktivisane retikulumske ćelije. Tumorski proliferati su predominantno sastavljeni od limfoblasta i imaju sve karakteristike limfoma. Imunohistohemijskom analizom je ustanovljeno da su ćelije limfoma kod MB predominantno T ćelijskog tipa, CD3 fenotipa. U proliferatu u jetri su nađene i brojne CD79 pozitivne ćelije lokalizovane perivaskularno, što predstavlja interesantan nalaz i zahteva dalja ispitivanja

Structure and immunohistochemistry of the human lenticulostriate arteries

Background: Data about the structure and immunohistochemistry of the lenticulostriatearteries (LSAs), although very important for medical research and clinicalpractice, have been rarely reported in literature.Materials and methods: Fourty serially sectioned LSAs were stained with hematoxilinand eosin, and prepared for immunohistochemistry.Results: Our examination revealed a typical endothelial lining and a narrow subendothelialspace with subintimal smooth muscle cells occasionally. The internalelastic lamina was fragmented or absent in the smallest LSAs branches. The mediacoat, with a mean diameter of 148.5 μm, contained typical smooth muscle cellswhich formed 14.2 layers on average and showed a positive immune reactions foralfa-actin, desmine, laminin and collagen IV. The thin adventitial coat containedfibroblasts, collagen fibers, and nerve bundles, with the strongest immunopositivityto thyrosin hydroxilase. The immune reactions against CD31 and CD34 proteins,endothelial nitric oxide synthase, S 100 protein, neurofilament protein and synaptophysin,seem to be performed in the LSAs wall for the first time. Similarly,the thickness of the LSAs wall and its coats have never been reported, nor thenumber of the smooth muscle cell layers.Conclusions: Our results related to the structure and immunohistochemistry ofthe LSAs could be important in cerebrovascular pathology, neurology and neurosurgery

A 3 tesla magnetic resonance imaging volumetric analysis of the hippocampal formation: dependence on handedness and age

Background: The hippocampal formation (HF) is one of the most important parts of the brain in the magnetic resonance imaging (MRI) volumetric analysis in various domains, but not completely from all aspects, including the handedness. The aim of our study was to evaluate the possible differences in the volume of the right and left HF among the healthy right-handed and left-handed subjects, and to determine whether the volume differences are age related. Materials and methods: The MRI of this prospective study was performed using T1 fast field echo (FFE) sequence. The 124 subsequent coronal slices (thickness 1.5 mm) were performed in each participant. The obtained HF volumes were normalised and statistically compared. Volunteers comprised 30 persons aged 22.0 years, 12 of whom were the left-handed, and 30 persons aged 75.2 years on average, 9 of whom were the left-handed. Results: The right and left HF volumes averaged 2.986 cm3 and 2.858 cm3 in the right-handed, and 2.879 cm3 and 3.020 cm3 in the left-handed young volunteers, as well as 2.728 cm3 and 2.650 cm3 in the right-handed, and 2.617 cm3 and 2.780 cm3 in the left-handed elderly persons. The HF volume ratios in the young left-handed participants showed a significant left-greater-than-right asymmetry. A significant difference was also noticed within the right-to-left volume ratios of the right- and left-handed young and elderly participants. The latter reduction in the HF volume within the aged group can be interpreted as a slight atrophy of the HF. Conclusions: There is a significant difference in the volumes of the left and right HF of the left-handed young participants. The age related HF volume differences were proven between the groups of the young and elderly volunteers. The obtained data should be included into the future MRI studies of the HF volumes in various clinical domains.

Simultaneous vapour deposition of uranium and carbon

During recent years simultaneous vapour deposition of carbon and various metals has been the subject of a number of papers (c.f.ref. 1). However, there are apparently no published data concerning simultaneous deposition of uranium and carbon. The purpose of this note is to present some recent data on the simultaneous pyrolytic deposition from a gas mixture with different proportions of UF-6 and CH-4 at temperatures ranging from 1400 to 1600 C and in the total gas pressure interval 50-150 mm Hg

Chemical vapour deposition of diamond using low pressure flat combustion flame

Diamond coatings were deposited onto Mo and WC-Co Substrates using a low pressure premixed acetylene-oxygen flat flame by means of a special apparatus operating at 50 mbar. Uniform diamond coatings containing significant amounts of non-diamond carbon were deposited over areas of approximate to 7 cm(2) onto Mo substrates, the coating thickness after 1 h deposition amounted to approximate to 1 mu m. Upon machining an Al-12 % Si alloy under identical conditions, the diamond coated WC-Co cutting tool inserts showed 30 % less wear than the as-receivcd inserts

Elastic scattering of electrons from alanine

Differential cross sections (DCSs) for elastic scattering of electrons from alanine, have been measured using a crossed beam system for incident energies between 20 and 80 eV and scattering angles from 10° to 150°. The experimental data were placed upon an absolute scale by normalisation to calculated absolute integral cross sections obtained using the corrected independent-atom method incorporating an improved quasifree absorption model. The calculated data-set includes DCSs and integral elastic and inelastic cross sections in the incident energy range between 1 and 10,000 eV. These theoretical results are found to agree very well with the experimental data both in the shape and magnitude of DCSs except at the smallest scattering angles

A comprehensive model integrating UTAUT and ECM with espoused cultural values for investigating users' continuance intention of using mobile payment

Zhao, Y., & Bacao, F. (2020). A comprehensive model integrating UTAUT and ECM with espoused cultural values for investigating users' continuance intention of using mobile payment. In Proceedings of the 2020 3rd International Conference on Big Data Technologies, ICBDT 2020 (pp. 155-161). (ACM International Conference Proceeding Series). Association for Computing Machinery. https://doi.org/10.1145/3422713.3422754Mobile payment (M-payment), as an emerging financial transaction method has been widely adopted in various contexts. In order to investigate the significance factors and espoused cultural moderators impacting users' M-payment continuance usage intention in China, this study proposes a comprehensive model integrating Unified Theory of Acceptance and Use of Technology (UTAUT) and Expectancy Confirmation Model (ECM) with trust variable espoused by Hofstede's cultural value to investigate factors affecting users' continuance intention of using M-payment. In addition, based on the proposed model, researchers can more accurately explain user' behavior not only corresponding technological perceptions, but also mental expectations and espoused cultural values for various technology continuance acceptance under different cultural background.publishersversionpublishe

The Synthesis of ZnMn2O4 by Glycine Nitrate Combustion and an Examination of Its Electrochemical Properties in Aqueous Solutions of ZnCl2 and NaNO3

To research potential replacements for LiMn2O4, this work carries out a synthesis of ZnMn2O4 (ZMO) through the glycine-nitrate combustion. XRPD validates its phase characterization; electron microscopy confirmed the presence of single phase ZMO in the form of curvy and rod-shaped sub-micron sized particles at an average of 113 nm. This work is novel for its electrochemical measurements of ZMO as a cathodic material for alkali-ion batteries, performed by cyclic voltammetry in aqueous solutions of ZnCl2 and NaNO3 ranging from 5 to 100 mV s–1 polarization rates, yielding stable capacities for both electrolytes. The highest capacities were obtained for the polarization speed of 5 mV s–1 for both electrolytes. Their cathode capacities were 11.3 and 27.2 mA h g–1 for ZnCl2 and NaNO3, respectively. Concerning Na-ions batteries, the surface storage is the deciding factor due to the adsorption of Na+ ions on the λ-MnO2 phase. Unlike Znions, Na+ ions cannot intercalate into the spinel structured materials