55 research outputs found
Computational characterization of novel nanostructured materials: A case study of NiCl
A computational approach combining dispersion-corrected density functional
theory (DFT) and classical molecular dynamics is employed to characterize the
geometrical and thermo-mechanical properties of a recently proposed 2D
transition metal dihalide NiCl. The characterization is performed using a
classical interatomic force field whose parameters are determined and verified
through the comparison with the results of DFT calculations. The developed
force field is used to study the mechanical response, thermal stability, and
melting of a NiCl monolayer on the atomistic level of detail. The 2D
NiCl sheet is found to be thermally stable at temperatures below its
melting point of ~695 K. At higher temperatures, several subsequent structural
transformations of NiCl are observed, namely a transition into a porous 2D
sheet and a 1D nanowire. The computational methodology presented through the
case study of NiCl can also be utilized to characterize other novel 2D
materials, including recently synthesized NiO, NiS, and NiSe
Aplicación de la teoría asintótica de los valores extremos al modelado de los riesgos de grandes incendios forestales
Se examinaron las cuestiones relativas a la aplicación de la teoría asintótica de los valores extremos al análisis de los riesgos de los incendios forestales anuales máximos por área. Como material de partida, el trabajo utilizó datos sobre las áreas de incendios forestales ocurridos en el territorio de la parte sur del territorio de Khabarovsk de Rusia durante el período de tiempo de 1968 a 2017. Para cada año, se seleccionó un incendio forestal máximo en el área del período de tiempo considerado. En total, fueron seleccionados 50 de estos incendios durante este período de tiempo (por el número de años en el período). Como resultado del análisis de esta muestra, se demostró que el conjunto general de áreas de tales incendios (de donde se tomó la muestra) tiene una distribución de probabilidad de valores extremos del primer tipo. Se obtiene una expresión analítica para la función de distribución de probabilidad de esta población general. Sobre la base del análisis de esta distribución, se proporciona una Predicción de los riesgos de ocurrencia y los períodos promedio de repetición de tales incendios para diferentes valores de área de combustión. El análisis mostró que en 87.5% de los casos en el territorio de la parte sur del territorio de Khabarovsk aparecerán los incendios forestales anuales de área máxima de 50 a 400 km2 con un intervalo de repetición de 1.2 del año. Es decir, casi todos los años, excepto en los casos raros en que se producirán incendios en otra área. Se supone que la distribución de las probabilidades de los valores extremos del primer tipo se aplica no solo al territorio forestal del territorio de Khabarovsk de Rusia, sino también a otras áreas forestales del mundo con grandes áreas de bosqu
ABOUT A NEW LEVEL OF SELF-ORGANIZATION IN THE AGRICULTURAL MANAGEMENT SYSTEM
Background. According to the UN FAO recommendations, it is necessary to produce one ton of grain for each inhabitant of the Earth for the production of bread and feed for livestock and poultry farming in order to obtain meat, milk, eggs, etc. However, the current level is 3 times lower, which confirms the relevance of the research.
Methods and means. In the article, based on a systematic analysis of existing approaches in agriculture, a systematic synthesis of high-tech technological processes in agriculture, as well as fire protection of farmland and forests, was carried out. Examples of modern solutions in this area are given, including monitoring of farmland and forests using unmanned drones, small aircraft and helicopters. The latest developments in the development of airships for these purposes are described, including methods patented by the authors for detecting and fighting fires using gas separation nanotechnology to replace water with atmospheric nitrogen.
Results. The conditions for self-organization of technological processes in agriculture are determined, on the basis of which the synthesis of the model of an "agro-fire combine-airship" is carried out, which combines "inside itself" not only the functions of fire extinguishing with separated atmospheric nitrogen, but also all agricultural technologies and precision farming techniques - "without tractors, seeders, combine harvesters, trucks and land reclamation systems. The results of the "energy assessment" of the effectiveness of the introduction of domestic innovations in this area are presented.
Conclusion. As a result of the research, it was concluded that agro-fire combines-airships can implement not only technologies for extinguishing landscape and forest fires, but also have an unrivaled quality in the organization of agriculture, due to the proposed integration of these innovative solutions
THE FIRST SEVERE ACUTE RESPIRATORY SYNDROME CASE IN RUSSIA
Clinical picture of SARS, dynamics, diagnostics, including laboratory diagnostics (ELISA, PCR), and treating are described
Paradox: Does liver insuffi ciency protect the patient? A hypothesis
Despite the fact that the key role of the liver in the formation of the immune response to injury is not in doubt, the mechanisms of weakening the immune response to infectious and noninfectious lesions in patients with hepatic failure remain unclear. We propose an original hypothesis of forming the ways to limit the amplitude of the systemic inflammatory response in patients with the end-stage liver disease. The basis of the hypothesis is the idea that as a result of reducing the intensity of the natural stimulation of membrane mCD14 receptors by the ligands of infectious nature, the basic mechanism of the systemic immune response induction by liver macrophages (Kupffer cells) is interrupted. According to the proposed hypothesis, in condition of liver failure, the synthesis of lipopolysaccharide-binding protein by hepatocytes is reduced. This leads to a decreased amplitude and intensity of the protective immune responses. This fact explains a number of clinical phenomena observed in patients with liver failure/dysfunction that consist in a reduced reactivity of the organism to the damage inflicted by infectious and noninfectious agents. The authors consider it possible to use this hypothesis in the search for new trends to prevent the immune system hyper-reactivity in sepsis, and to improve the therapeutic strategies for the management of patients at high risk of infectious complications after liver transplantation
Development of Typical "State" Software Patterns for CortexM Microcontrollers in Real TIME
There are real-time technical systems that require high speed of software solutions. At the same time, it is necessary to ensure the unification of the source code, the quality of software maintenance, and mathematical modeling at a relatively low cost of software and hardware solution. Such hardware can be implemented on the basis of mass microcontrollers of the Cortex-M architecture.The software part of these microcontrollers data could be implemented on the basis of a real-time operating system (RTOS). This study has found that the application of RTOS leads to a speed-related constraint. Simple software solutions are complex at unification, support, and have difficulties with mathematical modeling.To address these shortcomings, typical State software patterns have been developed for an auxiliary controller within a circuit of controlling mechanisms or sensors based on the Cortex-M architecture microcontroller in real time, in a procedural paradigm. A feature of these patterns is the higher speed of the software solution compared to the solutions based on RTOS.The developed patterns make it possible to unify the source code for the Cortex-M architecture microcontrollers from different manufacturers, improve maintenance, and adapt it to the mathematical model of the finite state machine.The study results were tested using the STM32F103 microcontroller employing the Cortex microcontroller software interface system (CMSIS) library. This allows the result obtained to be extended to MCs made by other manufacturers, which ensures the practical value of the developed patterns
A bottom-up approach for controlled deformation of carbon nanotubes through blistering of supporting substrate surface
International audienceTuning the band structure and, in particular, gap opening in 1D and 2D materials through their deformation is a promising approach for their application in modern semiconductor devices. However, there is an essential breach between existing laboratory scale methods applied for deformation of low-dimensional materials and the needs of large-scale production. In this work, we propose a novel method which is potentially well compatible with high end technological applications: single-walled carbon nanotubes (SWCNTs) first deposited on the flat surface of a supporting wafer, which has been pre-implanted with H + and He + ions, are deformed in a controlled and repetitive manner over blisters formed after subsequent thermal annealing. By using resonant Raman spectroscopy, we demonstrate that the SWCNTs clamped by metallic stripes at their ends are deformed over blisters to an average tensile strain of 0.15±0.03%, which is found to be in a good agreement with the value calculated taking into account blister's dimensions. The principle of the technique may be applied to other 1D and 2D materials in perspective
Kreativitas Mahasiswa pada Mata Kuliah Desain Ragam Hias di Jurusan Kesejahteraan Keluarga Fakultas Teknik Universitas Negeri Padang
This research is a descritive quantitave research. Research population are students on subject of design variety of decoration in the field of family welfare periode Januari to June 2013, the number of population are 37 students. Sampling technic is total technical sampling. Data collected by using questionairs likert scale. Tested questionnaire to students in the incoming year 2012 which took a course design ornament by 30 people. To determine logical validity of the instrument in order to be able to know instrument reliability with alpha cronbach formula. Reliability analysis shows that the reliability of questionare is in a very strong group, the data is analysed by technical percentage. Research result shows that in general students creativity is categorized in 4 sub indicators is indicators openness to new experience is in middle category 68,9%, indicators freedom to self express in middle category 66,3%, indicators appreciate fantasy is in middle category 65,5%, indicators respect to idea in middle category 65,0%. Based on score variable distribution in field of decoration variety, it is found not students creativity in the middle category, achievment of questioner analysis in the middle category 66,9%. To sum up that students creativity on subject of design variety of decoration in the field of family welfare faculty of technic state university of padang is middle category. Hint: Students Creativity, Subject Design Variety of Decoratio
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