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2021 ◽  
Author(s):  
Kaiwen Sun ◽  
Fangyang Liu ◽  
Xiaojing Hao

Kesterite Cu2ZnSnS4-xSex (CZTS) is a promising thin film photovoltaic (PV) material with low cost and nontoxic constitute as well as decent PV properties, being regarded as a PV technology that is truly compatible with terawatt deployment. The kesterite CZTS thin film solar cell has experienced impressive development since its first report in 1996 with power conversion efficiencies (PCEs) of only 0.66% to current highest value of 13.0%, while the understanding of the material, device physics, and loss mechanism is increasingly demanded. This chapter will review the development history of kesterite technology, present the basic material properties, and summarize the loss mechanism and strategies to tackle these problems to date. This chapter will help researchers have brief background knowledge of kesterite CZTS technology and understand the future direction to further propel this new technology forward.


2021 ◽  
Vol 23 (3) ◽  
pp. 431-444
Author(s):  
Elfrida Ratnawati Gultom ◽  
Endang Pandamdari

The problem that will be discussed in this article is about the inheritance rights of a widower according to the customary inheritance of the Batak Toba, whether the widower according to the customary inheritance law of the Batak Toba gets an inheritance from his wife's family. The type of normative legal research used in this article is supported by references or secondary data as the basic material for research related to the issues discussed, that is the rights of the inheritance of widowers in Batak Toba. The data sources used are primary data and secondary data. The data from the results of this study will be analyzed with a qualitative approach, then will be described descriptively. The conclusion obtained from this study is that a Toba Batak widower, in the customary inheritance law of the Batak Toba does not inherit from his wife's family because the wife is a family member of the husband (honest marriage), because the wife herself does not also get an inheritance fromhis parents, because in Batak Toba community, only sons (his wife's brother) get a share of the inheritance and become the heirs of the wife's parents.


Author(s):  
Alaa Ahmad Zohir Kattan, Nada Altonji, Fatima Alsaleh Alaa Ahmad Zohir Kattan, Nada Altonji, Fatima Alsaleh

In this research, the effect of adding some natural wastes to gypsum was studied in order to use them as thermal insulation materials in buildings and to recycle these wastes. Thermal insulation panels were installed from gypsum (as a basic material) and natural wastes (sawdust, peanut shells, wheat straw, cottonwood) at percentages (10, 15, 20) %, and some of their mechanical and physical properties, and their thermal conductivity were studied. The results indicated an improvement in some properties of gypsum after adding wastes, and obtaining thermal building materials that have better properties than the reference sample (gypsum) in some cases. Rough sawdust samples (SdR15, SdR20) achieved the highest compressive strength exceeding (4MPa). The flexural strength was for peanut shells samples (P10:1.76 MPa, P15:1.8 MPa), while the most efficient samples as thermal insulation were ground straw and smooth sawdust samples (SdS15, SdS20, GSt15, GSt20) where their thermal conductivity was (0.194-0.141W/m.K), which makes it acceptable according to the Syrian thermal insulation code.


Author(s):  
Тетяна Василівна Калінеску ◽  
Даніїл Сергійович Ревенко ◽  
Ігор Леонідович Мостіпан

The process of forming of certain economic strength security provides the proof functioning of business, its integration in control system by a region and state. Therefore, there is a permanent necessity for realization the monitoring of economic security of enterprise as a key element of steady development of national economy. A research aim is sent to forming of conceptual positions in realization of monitoring the systems of economic security of business. modern normatively-legal and legislative aspects became Methodological basis of research became modern normatively-legal and legislative aspects of strengthening of economic security and eliminate of existent threats in the process of realization the monitoring of economic security of different business structures. In the conducted researches used methods of dialectics, methods and principles of scientific cognition, instruments of economic analysis for the sake of forming the conceptual positions in relation to creation of monitoring the systems of economic security of business. The basic hypothesis of research became supposition about possibility of creation the universal conceptual bases of realization the monitoring of economic security of businessmen with the aim of providing of stable development of business activity in the different spheres of national economy. Exposition of basic material. In the article are investigated the basic requirements of creation the monitoring of the systems of economic security, that is pulled out on the modern stage of business development to marked the aim, tasks, principles, functions, and stages of realization the monitoring. It is brought indicators over of economic security and its threshold values on the different levels of management business activity, to underline, that for each separate business structure the indexes of economic security can be certain depending on the type of business. Originality and practical meaningfulness of research are confirmed by the offered conceptual bases to creation and realization of monitoring the systems of economic security of businessmen, which takes into attention the specific of activity the separate businessman, and allows to be integrated in the general system of the state economic security. Conclusions and prospects of further researches. It is well-proven that conceptual positions are offered the monitoring of the systems of economic security of business allow to recognize and identify threats, forecast its consequences, determine the methods of localization and give information for the management of business structure activity, to accept operative decisions on the removal of threats, to correct strategic aims of businessmen development, taking into attention the state of economic security of external and internal environment of functioning. Further researches will be sent to convergence of purposeful cooperations in the process of realization the monitoring in the system of economic security of enterprise


Author(s):  
Світлана Владиславівна Бурлуцька ◽  
Сергій Віталійович Бурлуцький

Use of the system approach to management of social and economic processes is connected with existence of the immanent contradiction caused by a high level of abstraction of the definition "system" and a considerable level of concreteness of real economic tasks. The mentioned thesis needs formalization of descriptors of socio-economic systems and identification of basic management contours. The purpose of the article is to substantiate the necessity of using a systematic approach to the construction of the socio-economic system construct based on the identification of relevant descriptors and management contours. The methodological basis of the study was a combination of the Marxist school of political economy, the modern economic mainstream and unorthodox currents within the systemic paradigm. The main hypothesis of the study was the assumption regarding the possibility and feasibility of using descriptive methodology of systems identification to the needs of management of socio-economic systems. Statement of the basic material. On the basis of the analysis, a certain basis is provided for the formation of correlations of correspondence of the descriptors of the national socio-economic system to the corresponding axiomatic conditions and basic components. It is proved that the dualistic understanding of the individual as an economic and institutional basic element of the socio-economic system is fully appropriate to the understanding of the essence of the national economy. Institutions should be seen as a structure of connections that combine the elements into a unified integrity. It is proved that the state and its institutions play a dialectical role in ensuring the integral existence of the national socio-economic system of market type. Originality and practical significance of the research. The resulting theoretical and methodological concept has theoretical significance and can be transformed into relevant tools for the development of scientific and practical recommendations on the management of socio-economic systems. Conclusions and prospects for further research. The results of generalization of theoretical statements on the essence and content of the definitions of "socio-economic system" and "national economy" led to the conclusion about the impossibility of considering the economic subsystem (national economy) separately from other subsystems. The expediency and sufficiency of the use of the definition "national socio-economic system" as more acceptable for solving the dialectical unity of social and economic subsystems of society was proved. Further research will focus on the development of the methodical support for the identification of management contours on the basis of socio-economic descriptors


Author(s):  
Toreniyazov Elmurat Sherniyazovich ◽  
Yusupov Rysnazar Orazbaevich ◽  
Eshmuratov Elbrus Gaybullaevich

The article presents information about fields of agricultural production of the Republic of Karakalpakstan, the increase of the requirement for food as a result of increasing the number of population. It was shown that it is important to synthesize pistil of the pest, which is the basic material, in making pheromone capturers of the most dangerous pest of agricultural crops – melon fly. In this, capturing instrument, collecting orders of worms and pupas with the help of protector small gardens were shown. KEYWORDS: melon fly, pistil pest, worm, pupa, capturer, small protecting gardens, collecting.


2021 ◽  
Vol 12 (1) ◽  
pp. 98
Author(s):  
Andrej Chríbik ◽  
Marián Polóni ◽  
Ľuboš Magdolen ◽  
Matej Minárik

The aim of the presented article is to analyse the influence of synthesis gas composition on the power, economic, and internal parameters of an atmospheric two-cylinder spark-ignition internal combustion engine (displacement of 686 cm3) designed for a micro-cogeneration unit. Synthesis gases produced mainly from waste contain combustible components as their basic material (methane, hydrogen, and carbon monoxide), as well as inert gases (carbon dioxide and nitrogen). A total of twelve synthesis gases were analysed that fall into the category of medium-energy gases with lower heating value in the range from 8 to 12 MJ/kg. All of the resulting parameters from the operation of the combustion engine powered by synthesis gases were compared with the reference fuel methane. The results show a decrease in the performance parameters for all operating loads and an increase in hourly fuel consumption. Specifically, for the operating speed of the micro-cogeneration unit (1500 L/min), the decrease in power parameters was in the range of 7.1–23.5%; however, the increase in hourly fuel consumption was higher by 270% to 420%. The decrease in effective efficiency ranged from 0.4 to 4.6%, which in percentage terms represented a decrease from 1.3% to 14.5%. The process of fuel combustion was most strongly influenced by the proportion of hydrogen and inert gases in the mixture. It can be concluded that setting up the synthesis gas production in the waste gasification process in order to achieve optimum performance and economic parameters of the combustion engine for a micro cogeneration unit has an influential role and is of crucial importance.


2021 ◽  
Vol 2 (1) ◽  
pp. 44-50
Author(s):  
Wazirotus Sakinah

Grenden Village has the highest number of households in Puger District. Generally, the habit of the people there in managing their waste are throwing it into rivers and the sea. This is the main cause of flooding in that area. One of the efforts to reduce the production of plastic waste is ecobrick. Ecobricks products are the basic material for making tables, chairs, and building materials because they have the strength to withstand loads according to the specified weight. The youth in Grenden village are agents of change who are the object of service to tackle plastic waste in their area. This service activity has 3 stages, (1) socialization regarding the impact of plastic waste disposal in the waters and the introduction of ecobricks, (2) training on making ecobricks, and (3) marketing the results of ecobricks into e-commerce. Participants were very enthusiastic about being directly involved in filling ecobricks with plastic waste and were very confident that they would be able to make more ecobricks in the future by collecting the plastic waste they produce. This positive response is a small step for good changes for the environment, especially in Grenden village.


2021 ◽  
Vol 15 (2) ◽  
pp. 76-83
Author(s):  
József Richárd Lennert ◽  
József Sárosi

The aim of this study is to investigate the effect of layer height used during 3D printing on the impact strength, their standard deviations, and the printing time by using UNI EN ISO 180 unnotched specimens manufactured by FDM 3D printing technology. Every specimen is made of PLA, which is the most basic material of the FDM printing technology by using the same 3D printer. In this study it plays a key role to find out whether the layer height can be used to optimize the researched mechanical property within an economical framework or not. What is more, the possibly observable tendencies and crucial influential parameters will be analysed as well.


2021 ◽  
Author(s):  
Ryo Takahama ◽  
Honami Kato ◽  
Go Takayama ◽  
Kenji Tajima ◽  
Tetsuo Kondo

Abstract This study attempts to clarify the basic material properties of in-vivo-fabricated hyaluronan (HA)/bacterial cellulose (BC) nanocomposites prepared previously. BC membranes (pellicles) generated by Gluconacetobacter hansenii (G. hansenii) are promising biomaterials owing to their outstanding biocompatible properties. Recently, specific demands for biomedical applications of BC have increased owing to its excellent mechanical properties. Although many techniques have been developed to improve the biofunctional properties of BC pellicles, such modifications remain limited owing to technical difficulties in the modulation of complex biosynthetic processes. Therefore, we previously developed an in vivo modification technique to produce nanocomposite pellicles composed of BC and HA (in vivo HA/BC), which are directly secreted from genetically engineered G. hansenii. In the present study, the HA extractability and content rate, physical characteristics, and cytocompatibility of in vivo HA/BC have been investigated in comparison to conventional in situ HA/BC and native BC pellicle. The results suggested that HA more strongly adsorbed to the solid BC surface of in vivo HA/BC than that of in situ HA/BC, which possibly affected the dynamic viscoelastic characteristics. Furthermore, in vivo HA/BC showed remarkably high human epidermal cell adhesion. These results indicate the great potential of in vivo modification to expand the usefulness of BC-based biomaterials.


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