In lithium-ion batteries, the electrochemical reaction between the electrodes and lithium is a critical process that controls the capacity, cyclability and reliability of the battery. Despite ...intensive study, the atomistic mechanism of the electrochemical reactions occurring in these solid-state electrodes remains unclear. Here, we show that in situ transmission electron microscopy can be used to study the dynamic lithiation process of single-crystal silicon with atomic resolution. We observe a sharp interface (~1 nm thick) between the crystalline silicon and an amorphous Li(x)Si alloy. The lithiation kinetics are controlled by the migration of the interface, which occurs through a ledge mechanism involving the lateral movement of ledges on the close-packed {111} atomic planes. Such ledge flow processes produce the amorphous Li(x)Si alloy through layer-by-layer peeling of the {111} atomic facets, resulting in the orientation-dependent mobility of the interfaces.
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•A novel multigeneration wind-solar energy system integrated with near-zero energy building is investigated.•The system consists of wind turbine, PTC collector, hot water storage ...tank, CAESS and absorption chiller.•All building loads along with the operating parameters of the cycle were calculated on an hourly basis for a year.•A dynamic model based on 4E analyses for evaluating the suggested system is developed.
This work focuses on a dynamic model of an innovative multigenerational solar-wind-based system from energetic, exergetic, economic, and environmental approaches. It is integrated to a near-zero energy building in St. Petersburg of Russia, with the purpose of covering the hourly cooling, heating, and electricity loads of the building. It consists of a wind turbine, a parabolic trough solar loop, an absorption chiller, and a compressed air energy storage system. A gas heater is also used to meet the total heating load of the system at off-peak hours of solar energy and becomes the main source of energy in some months. A comprehensive model is developed and the feasibility of the solar and wind energy is investigated dynamically on the proposed system. Results of the study show that the proposed solar system can cover up to 61 % of the yearly heating loads of the building, and the system. The required heat load of the system itself includes the heat demand of the absorption chiller, and the compressed air storage system. It is also noticeable that the presented energy storage system provides almost 99 % of the required electricity load beside the wind turbine and the rest of it needs the grid connection. In January, 13 % of the electricity demand is supplied from the grid and in the last three months, nearly 69 % of produced power of wind turbine is sold to the grid. This system leads to 13859 kg/year of CO2 emission reduction due to heating, cooling, and electricity. Moreover, the maximum monthly energy and exergy efficiencies are achieved in December with amounts of 41 % and 11 %, respectively. Finally, from the economic analysis, it is found that the positive amount of net present value is accessible after 12, 14, and 17 years, assuming interest rates of 1 %, 3 %, and 5 %, respectively.
To demonstrate own experience in 3D modeling for planning of minimally invasive approach to the orbit and anterior skull base.
A 17-year-old patient admitted to the Department of Pediatric ...Neurosurgery with complaints of decreased visual acuity of the left eye, lacrimation and exophthalmos. MRI revealed a tumor of the left orbit. We have preoperatively modeled frontoorbital region, anterior skull, as well as eyeball and tumor within the same model. Considering young age and potentially favorable prognosis of disease, we preferred a minimally invasive intervention (microsurgical resection of tumor through minimally invasive frontoorbital access).
Total resection of tumor was followed by examination of anterior skull base. There was postoperative regression of visual disturbances, lacrimation and exophthalmos. Sutures were removed after 5 days, and the patient was discharged.
Minimally invasive frontoorbital access is adequate for approach to the orbit, anterior and middle cranial fossa, adequate resection of orbital tumor and examination of anterior skull base. 3D modeling is an additional preoperative tool to improve the quality of preoperative planning and facilitate intraoperative navigation.
Currently, 3D-printing technologies are increasingly used in neurosurgery. Active development of this approach is valuable to improve preoperative planning, intraoperative navigation, and ...manufacturing of realistic training models. In this manuscript, the authors report an experience of the pediatric neurosurgical department of the Almazov National Medical Research Center regarding 3D-printing technologies in manufacturing of individual implants for skull defect closure. The main aspects of this technology, advantages and disadvantages are considered. Moreover, the authors describe several cases of creating individual implants for children with skull defects of various origins, dimensions and complexity.
Abstract
Buildings especially heating systems consume a prodigious amount of energy. In this case, the heated exhaust air from the premises is simply thrown out into the external environment, into ...the street. In this work, such air is considered as a secondary energy resource formed from the internal loads of the room. The study of the dynamics of changes in the power of internal loads and their influence on the operation of the heat exchanger installed on the exhaust was carried out using the Energy Plus software package. The simulation result showed the potential of using the heat of the exhaust air as an energy resource. The recovered heat from the extract air can be used to partially reduce the energy consumption for the heating system.
Abstract
The analysis of outdoor climate normative information, given in the form of calculated parameters of outdoor air for warm and cold periods of the year, is given. The requirements to the form ...of presentation of climatic information and to its content are formulated. The information is presented in the form of tables of recurrence of outdoor parameters in two-dimensional intervals for different cities of the Russian Federation and the capital of Iraq, Baghdad. It is shown that the information in the form of these tables can be used for the tasks indicated in the article at the stage of conceptual design of air conditioning system. The results of approbation of the considered form of climate information implemented at practical tasks are demonstrated. Among these results, we should pay special attention to dependence of installation capacities of subsystems on the time of non-availability of the rated parameters of the air environment in a room. Moreover, it is shown by the example that information about heat, cold, air, and water consumption by heat and humidity treatment in air conditioning systems can be determined for various calculated periods of time. The results were obtained using an applied computer program that executes the recommended form of presentation of climate information for the design of air conditioning systems.
The article is devoted to the development of the mathematical model of mass (cadastral) evaluation of agricultural land plots belonging to the agricultural organizations located in the Leningrad ...Region. On the basis of the initially selected composition of the cadastral value pricing factors, by applying the expert method of Analytic hierarchy process, the most significant ones were identified. Using the Pareto method, the factorial indicators were ranked according to the degree of their influence on the value of land. As a result of the research, the evaluative model of the cadastral value of agricultural land was constructed and tested according to the main indicators of the modeling quality.
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