Test trials of a process to produce briquettes from coal mining waste

2021 ◽  
pp. 93-96
Author(s):  
T. A. Ketegenov ◽  
K. Kamunur ◽  
T. I. Yushina ◽  
S. N. Kalugin
Keyword(s):  
Fine Fraction ◽  
Physical And Mechanical Properties ◽  
Added Value ◽  
Coal Waste ◽  
Chemical Processing ◽  
Ministry Of Education ◽  
Production Wastes ◽  
Grant Support ◽  
National University ◽  
Coal Fines

At the present time, coal production wastes up to 2 % of fine fraction, which has adverse impact on the environment. On the other hand, coal fines can be a feedstock to obtain different products of chemical processing—benzines, oils, briquettes, etc. For this reason, it is necessary to develop dedicated technologies to utilize fine waste in manufacture of products having high added value. The experimental results demonstrate usability of wheat bran as a binder in coal waste briquetting. It is found how the binder and the briquetting conditions influence the physical and mechanical properties and combustion characteristics of coal briquettes. The optimized coal briquetting conditions are: carbonization of feedstock, use of binder in quantity of 25–30 mass%, briquetting pressure of 4 MPa. Thus, the authors have analyzed the influence of the briquetting conditions on the properties of coal briquettes, and have tested the earlier developed approaches to transformation of Oi-Karagai coal fines into a target product of high added value. The authors appreciate participation of A. Karagulanov, fellow of the Al-Farabi Kazakh National University in this study. The work was performed with the grant support of the Ministry of Education and Science RK-A RO 08957618.

scholarly journals Study of Aquilaria crassna Wood as an Antifungal Additive to Improve the Properties of Natural Rubber as Air-Dried Sheets

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4178
Author(s):  
Phattarawadee Nun-Anan ◽  
Sunisa Suchat ◽  
Narissara Mahathaninwong ◽  
Narong Chueangchayaphan ◽  
Seppo Karrila ◽  
...  
Keyword(s):  
Natural Rubber ◽  
Fungal Growth ◽  
Physical And Mechanical Properties ◽  
Significant Inhibition ◽  
Added Value ◽  
High Plasticity ◽  
Green Strength ◽  
Unpleasant Odor ◽  
Negative Impacts ◽  
Aquilaria Crassna

Fungal growth on rubber sheets confers inferior properties and an unpleasant odor to raw natural rubber (NR) and products made from it, and it causes environmental concerns. The purpose of the present work was to investigate the effects of Aquilaria crassna wood (ACW) on the antifungal, physical and mechanical properties of NR as air-dried sheets (ADS) and ADS filled with ACW. The results show that the ACW-filled ADS had an increased Mooney viscosity, initial plasticity (PO), and high thermo-oxidation plasticity (i.e., high plasticity retention index PRI). Additionally, superior green strength was observed for the ACW-filled ADS over the ADS without additive because of chemical interactions between lignin and proteins in NR molecules eliciting greater gel formation. A significant inhibition of fungal growth on the NR products during storage over a long period (5 months) was observed for ACW-filled ADS. Thus, it can be concluded that ACW could be applied as an antifungal additive that reduces fungal growth. This is a practically important aspect for the rubber industry, as fungal growth tends to spoil and cause the loss of NR sheets during storage. Moreover, the ACW is active as an incense agent, reducing negative impacts from odors that fungi, on rubber surfaces, release. Therefore, these filled intermediate NR products provide added value through, an environmentally friendly approach, this is pleasant to customers.

Wood anatomical and topochemical analyses to characterize juvenile and adult wood of lesser-known species from Central America (Mexico)

IAWA Journal ◽  
2019 ◽  
Vol 40 (4) ◽  
pp. 785-803 ◽  
Author(s):  
Volker Haag ◽  
Gerald Koch ◽  
Hans-Georg Richter ◽  
Robert Evans ◽  
José Antonio Silva Guzmán ◽  
...  
Keyword(s):  
Central America ◽  
Fibre Length ◽  
Physical And Mechanical Properties ◽  
Wood Properties ◽  
Added Value ◽  
Individual Species ◽  
Image Analysis System ◽  
Acetone Water ◽  
Analysis System ◽  
Tabebuia Rosea

ABSTRACT Anatomical and subcellular characteristics of juvenile and adult wood of seven species (Manilkara zapota (L.) P. Royen, Platymiscium yucatanum Standl., Lonchocarpus castilloi Standl., Roseodendron donnell-smithii (Rose) Miranda, Terminalia buceras (L.) Wright, Tabebuia rosea (Bertol.) DC., Lysiloma latisiliquum (L.) Benth. from Mexico, including a histometric evaluation, were investigated by light microscopy with a digitized image analysis system and by X-ray diffractometry using the SilviScan® system. The topochemical distribution of lignin and phenolic deposits in the tissue was studied by means of cellular UV-microspectrophotometry (UMSP). Extractive contents (acetone/water and water) were determined gravimetrically. The results of the structural and topochemical analyses were compared with the interrelations of certain anatomical and subcellular structures as well as the topochemical composition with regard to the physical and mechanical properties of the timbers investigated. The objective was to provide a detailed cellular and subcellular description of the heartwood of seven lesser-known timbers from Central America. All examined tree species show significant differences between juvenile and adult heartwood. For individual species, however, the differences vary greatly and have to be individually assessed in addition to general trends observed for all studied species. It has been shown that vessel size, fibre length, size of fibre lumina, and height and width of rays, as well as the content of extractives and topochemical composition of the cell walls, are suitable indicators for the differentiation of the two heartwood types. The results also contribute to a better understanding of the wood properties of the investigated timbers in relation to their utilization and added value increase.

scholarly journals Studies of the Possibility of Using Coal Mining Waste in Concrete for Mine Construction

2020 ◽  
Vol 174 ◽  
pp. 01012
Author(s):  
Natalya Gilyazidinova ◽  
Vladimir Duvarov ◽  
Akparali Mamytov
Keyword(s):  
Coal Mining ◽  
Liquid Glass ◽  
Setting Time ◽  
Fine Fraction ◽  
Mining Waste ◽  
Coal Waste ◽  
Technological Parameters ◽  
Optimum Quantity ◽  
Coal Wastes

The article discusses the possibility of using coal waste for the preparation of mine concrete. As a result of the research, scientific and prac- tical results were obtained. It has been experimentally proved that when a small fraction of coal, which is a waste of coal mining, is added to mine concrete, the strength of concrete decreases, but with a certain ratio of this strength it is sufficient to ensure the required properties. A series of experi- ments was carried out with the addition of liquid glass to the concrete to control the setting time of the mixture. The properties of coal wastes were determined and the possibility of their use in mine concrete was investigated. It has been established that the introduction of a fine fraction of coal in the optimum quantity into the composition of mine concrete is possible without reducing technological parameters.

Loading of bearing retaining pin of tricone drill bit

2020 ◽  
pp. 64-67
Author(s):  
D. I. Simisinov ◽  
◽  
A. I. Afanasiev ◽  
V. S. Shestakov ◽  
N. G. Valiev ◽  
...  
Keyword(s):  
Strain Analysis ◽  
Physical And Mechanical Properties ◽  
Contact Stresses ◽  
Drill Bit ◽  
Ministry Of Education ◽  
Drill Bits ◽  
Bending Loads ◽  
Bearing Assembly ◽  
Engineering Changes ◽  
Cone Drill

Improvement of cone drill bit design is an engineering challenge as it is connected with considerable energy to be transferred via the drill to well bottom in the limited well space. In such conditions, it is difficult to create a full-size bearing assembly, including bearings and lubricating devices, as well as the sufficiently efficient cutting structure of the bits. Moreover, the condition of equal lives of the cutting structure and the bearing assembly is to be fulfilled. The operating practice of tricone drill bits in shothole drilling reveals their low serviceability. The life of a bit ranges from a few hours to a few days subject to physical and mechanical properties of rocks. The main cause of bit failure is damage of the retaining pin shoulder rivet under high contact stresses. Aimed at improvement of cone drill bit design and justification of engineering changes, the stress–strain analysis of the bearing retaining pint is performed, and it is found that the pin shoulder rivet experiences essential contact stresses and bending loads. It is proposed to equip cone drill bits with circulation lubrication system for the bearing assembly. Lubrication improvement can ensure reduction in loading of the bearing assembly components and, consequently, provide higher durability and wear resistance of these parts. The study was supported by the Ministry of Education and Science of Russia according to the state contract with the Ural State Mining University, Contract No. 0833-2020-0007.

A phantom to kill: The challenges for Chinese learners to use English as a global language

English Today ◽  
2014 ◽  
Vol 30 (4) ◽  
pp. 34-39 ◽  
Author(s):  
Yongyan Zheng
Keyword(s):  
First Language ◽  
Language Education ◽  
School Curriculum ◽  
Ministry Of Education ◽  
System A ◽  
National University ◽  
Primary School Curriculum ◽  
Global Language ◽  
Time And Energy ◽  
The Guardian

Very recently, the former spokesman of China's Ministry of Education launched a public attack on the national fervor for English learning in his personal blog (Xinhua News, 2013). He forcefully argued that too much time and energy has been spent on learning English as a foreign language, which has seriously jeopardized Chinese citizens’ first-language education, and called for the cancellation of English lessons in the primary school curriculum. Following this, the Beijing municipal commission of education announced its plan to reduce the English section of the National University Entrance Qualifying Exam (or gaokao) from 150 points to 100 points in major cities by 2016 so as to downplay the importance of English in the education system. A further report states that education authorities are also considering scrapping mandatory English lessons before the third grade. Shandong and Jiangsu provinces, as well as Shanghai, may remove English from the gaokao entirely (The Guardian, 2013).

scholarly journals Orthotopic liver transplantation of pigs using porto/caval-jugular shunt for research work or off-site training of young surgeon

2021 ◽  
Author(s):  
Masashi Kadohisa ◽  
Yukihiro Inomata ◽  
Hiroo Kasamatsu ◽  
Shinji Torai ◽  
Syuhei Yoshimoto ◽  
...  
Keyword(s):  
Liver Transplantation ◽  
Liver Transplant ◽  
Research Work ◽  
Ministry Of Education ◽  
Practical Procedure ◽  
Sports Science ◽  
Young Surgeon ◽  
Model Animal ◽  
National University ◽  
Large Animals

Abstract Although the training of liver transplant procedure is highly important to young transplant surgeons, it is too hard to secure the learning opportunity, especially in the countries like Japan whose organ transplants from deceased-donors are relatively rare. In such a situation, the surgical training in large animals such as pigs seems to be helpful in improving their skills. Consequently, under the assist by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) in Japan, we established a simulation work of whole liver transplantation using laboratory pigs in the context of interinstitutional frame called the Six National University Consortium in Liver Transplant Professionals Training (SNUC-LT) Program. For this purpose, in this procedure, to guarantee stable circulatory dynamics during the anhepatic phase of pigs, we created a porto-caval-jugular shunt which is followed by addressing liver dysfunction, portal hypertension and intestinal congestion. Here, we describe the precise practical procedure. We believe that our procedure enables young transplant surgeons to gain surgical skills efficiently and effectively in addition to making a model animal in an experimental field.

scholarly journals The reality of Vietnamese language teaching and Vietnamese Studies education in Korea

2015 ◽  
Vol 18 (2) ◽  
pp. 70-80 ◽  
Author(s):  
Minh Thi Hong Le
Keyword(s):  
Language Teaching ◽  
Entrance Examination ◽  
Ministry Of Education ◽  
Second Languages ◽  
National University ◽  
Supply Capacity ◽  
Vietnamese Studies ◽  
University Entrance Examination

Over 20 years of Korea-Vietnam relationship, Korea has become the biggest investor in Vietnam, and Vietnam the forth on the list of Korea’s most important partners. There are over 135,000 Koreans living in Vietnam and out of 123,000 Vietnamese living and working in Korea, there are 40,000 Vietnamese wives to Korean husbands. Currently, in Korea there are 4 universities that have faculties or departments of the Vietnamese language or of Vietnamese Studies, with a large number of alumni who have successfully found jobs. Demand is higher than supply capacity. Vietnamese proficiency is not only essential to Koreans living and working in Vietnam and Korea-based companies with Vietnamese employees but also will be valuable to children of thousands of Korean-Vietnamese families in the coming years. The Ministry of Education of Korea has just announced a policy stating that the Vietnamese language will be one of the eight second languages in the national university entrance examination, which will bring to Vietnamese language teaching new opportunities and prospects.

GENERALIZED LIST OF PUBLICATIONS IN THE SCIENTIFIC COLLECTION “HYDROLOGY, HYDROCHEMISTRY AND HYDROECOLOGY” FOR 2016-2020

2020 ◽  
pp. 88-104 ◽  
Author(s):  
V.K. Khilchevskyi
Keyword(s):  
Water Resources ◽  
Ministry Of Education ◽  
Scientific Publications ◽  
Scientific Periodical ◽  
National University ◽  
Methodological Aspects

The list of publications in the scientific periodical collection “Hydrology, hydrochemistry and hydroecology” for 2016-2020 is given. The scientific collection “Hydrology, hydrochemistry and hydroecology” was founded in May 2000 at the Taras Shevchenko National University of Kiev. In 2009, the collection was registered with the Ministry of Justice of Ukraine. The last recertification at the Ministry of Education and Science of Ukraine was in 2016 – the collection is included in the list of specialized scientific publications of Ukraine in the field of “Geographical Sciences”.In the formation of the collection of articles are grouped into five main sections: general methodological aspects of research; hydrology, water resources; hydrochemistry, hydroecology; hydroecology, hydrobiology; geographical aspects of hydroecological research. For the years 2016-2020. The collection contains about 270 publications. In total for the period 2000-2020. in 56 issues, about 1410 publications were published.

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