Study of the Boron Effect on the Physicochemical Properties of Ligatures

2021 ◽  
Vol 410 ◽  
pp. 254-261
Author(s):  
Aleksandr I. Cherepanov ◽  
Viktor A. Kukartsev ◽  
Vladislav V. Kukartsev
Keyword(s):  
Chemical Composition ◽  
Aluminum Alloys ◽  
Boron Content ◽  
Casting Rate ◽  
Accelerated Cooling ◽  
Master Alloys ◽  
Zonal Segregation ◽  
Materials Used ◽  
The Cost

One of the effective ways to improve the quality of semi-finished products made from aluminum alloys is to eliminate the columnar and fan-shaped structure in them, refine the grain and achieve homogeneity, is modification and alloying. Modification of the melt is carried out using ligatures and allows a significant increase in the casting rate without fear of an excessive increase in the degree of zonal segregation during crystallization, as well as ensuring the uniformity of the chemical composition over the section. An important role in the quality of modification is also played by the manufacturing technology of the master alloy itself, which should ensure an increase in the cooling rate during crystallization. To obtain an alloy with the required properties, the quality of the charge materials used must be considered. First of all, this concerns master alloys, which are used for alloying and modifying the alloy. The most common for the manufacture of ingots and shaped castings are master alloys containing boron or boron and titanium. The boron content in these ligatures is 1-5%. It is generally accepted that a large amount of boron (except for the rise in the cost of the alloy itself) upon accelerated cooling promotes the refinement of the internal structure of the grain, but can lead to an increase in large inclusions of TiB2.

scholarly journals PRODUKSI MASAL INOKULUM AZOTOBACTER, AZOSPIRILLUM DAN BAKTERI PELARUT FOSFAT DENGAN MENGGUNAKAN MEDIA ALTERNATIF

2010 ◽  
Vol 12 (2) ◽  
pp. 33
Author(s):  
Richard Gunawan ◽  
Iswandi Anas ◽  
Fahrizal Hazra
Keyword(s):  
Nutrient Broth ◽  
Phosphate Solubilizing Bacteria ◽  
Bacterial Cells ◽  
Microbial Cells ◽  
Nutrient Broth Medium ◽  
Growing Medium ◽  
Materials Used ◽  
Phosphate Solubilizing ◽  
The Cost

<p>Azotobacter, Azospirillum and phosphate solubilizing bacteria are the most common microbial inoculants used as biofertilizer. To have good quality of biofertilizer, the high number of inoculant cells and suitable carriers as well as the method of carrier sterilization are among the most important factors determined the quality of biofertilizer. Related to the number of inoculant cells in carriers, the growing medium used to cultivate the microbial cells play very important role. For mass production of microbial cells, the medium should be able to support fast growth of microbial cells. The price of medium should be reasonably cheap and the materials used in medium should be available easily. The purpose of this study was to obtain a cheap growing medium that can support high number of microbial inoculant cells and the components of the medium should be easyly obtain and the price is not expensive. The study was conducted at the Department of Soil Science and Land Resources, Faculty of Agriculture, Bogor Agricultural University (IPB). The results showed that the medium IPB RI-1 was able to support the growth of 1010 cfu ml-1 Azotobacter, 108 cfu ml-1 Azospirillum and 109 cfu ml-1 Phosphate Solubilizing Bacteria. The number of bacterial cells in Nutrient Broth medium was only 108 cfu ml-1. This means that the IPB RI-1 medium was able to produce 100-fold population of Azotobacter compared to the growth of this bacterium in Nutrient Broth and Phosphate Solubilizing Bacteria was 10-fold higher than population in Nutrient Broth medium. The costs of the IPB RI-1 and IPB RI-2 were much cheaper compared to the cost of Nutrient Broth medium. The cost of medium IPB RI-1 only 3% (IDR 945) and IPB RI-2 about 2% (IDR 690) of the cost of Nutrient Broth medium (IDR 27,752) per liter medium in the year of 2010.<br />Keywords : Alternative media, Azotobacter, Azospirillum, Nutrient Broth, Phosphate Solubilizing Bacteria</p>

scholarly journals Development of technology for obtaining starch gluing modified with uzkhitan and hydrolyzed emulsion

2021 ◽  
Vol 2094 (4) ◽  
pp. 042070
Author(s):  
Salokhiddin Mardonov ◽  
Laziz Shokirov ◽  
Khakim Rakhimov
Keyword(s):  
Theoretical Analysis ◽  
Rheological Properties ◽  
Carboxymethyl Cellulose ◽  
Corn Starch ◽  
Acrylic Emulsion ◽  
Pass Through ◽  
Materials Used ◽  
The Cost

Abstract In this article, in order to reduce the consumption of starch for gluing warp threads and reduce the cost of sizing materials used in sizing and improve the quality of threads, an effective gluing composition was created based on a hydrolyzed acrylic emulsion (GAE) and uzkhitan (chitosan and carboxymethyl cellulose), that is, corn starch polymer and studied their rheological properties. In the article, the main threads passing through the gluing process and moving at a certain speed, which are then impregnated with liquid gluing. Then they pass through a nip roller and a drying drum, are subjected to friction and form a layer of a certain thickness. A theoretical analysis of the surface of the warp threads is carried out to determine the change in the diameter of the threads when a layer of a certain thickness is formed on their surface.

Osteosynthesis Material Failure: Poor Fixation or Material Defect

2013 ◽  
Vol 717 ◽  
pp. 249-252
Author(s):  
Catalin Cirstoiu ◽  
Razvan Ene ◽  
Dan Popescu ◽  
Monica Cirstoiu
Keyword(s):  
Chemical Composition ◽  
Orthopedic Implants ◽  
High Energy ◽  
Global Scale ◽  
Macroscopic Appearance ◽  
Material Defects ◽  
Osteosynthesis Material ◽  
Valuation Technique ◽  
Materials Used

Rising rate of high energy trauma, mainly due to increasing life expectancy of the population on a global scale in recent decades and more intense daily activity, involves the need to address the increase of more complex fractures, thus putting to the test the experience of trauma surgeon and the quality of various osteosynthesis materials. Metallic materials designed for orthopedic implants must present a group of properties that strength, biocompatibility and resistance to degradation (corrosion or wear) are of primary importance. To reach these objectives, the materials used in the manufacture of orthopedic implants must meet standard requirements. These requirements include primarily standard chemical composition, microstructure and macroscopic appearance. In this paper we present a study to determine the cause of degradation of osteosynthesis material. The most frequent causes of degradation include poor or unstable fixation of osteosynthesis or material defects. A valuation technique, including optical and scanning electron microscopy (SEM) was used to assess aspects of macroscopic and microstructural degradation and chemical composition of implants. These assessments showed that both design errors and inappropriate surgical procedures were due to failures.

scholarly journals Cast iron rolls

2019 ◽  
Vol 13 (2) ◽  
pp. 92-99
Author(s):  
Imre Kiss
Keyword(s):  
Cast Iron ◽  
Chemical Composition ◽  
Laboratory Research ◽  
Graphical Form ◽  
Proper Solution ◽  
Regression Equations ◽  
Definite Structure ◽  
Materials Used ◽  
Nodular Graphite

The manufacturing process of the rolling rolls, as well as the quality of materials used in casting them, can have an important influence upon the quality and the safety of the exploitation. Our approaches to the issue of quality assurance of the rolling rolls, from the viewpoint of the quality of materials that are featured, can cause duration and safety in the rolling exploitation. This research is required because of the numerous flaws that cause rejection, since the phase of melting of these irons is intended to cast rolls. According to the industrial analysis in the cast iron rolls foundries, the results show that one of the main rejection categories is due to the inadequate hardness of the rolls. One of the parameters that will determine the cast iron’s structure is the chemical composition, and this factor could assure the exploitation properties of each roll in all the stands of rolling mill. In this sense, the paper presents an overview of industrial and laboratory research regarding the assurance of the chemical composition of the irons (with nodular graphite) destined for the half–hard rolls casting, and tries to draw some remarks upon the proper correlations of these irons. This study analyses iron rolls cast in combined moulds (iron chill, for the barrel and moulding sand, for the necks of rolls) and includes charges of rolls from half–hard classes, with definite structure and nodular graphite, obtained in simplex cast processes. It presents, in graphical form, the influence of the chemical composition of these irons on the hardness, measured on the barrel. The proper solution is determined through some mathematical restrictions to the input data that the mathematical modelling is initiated with. It will be determined through regression equations, which describe the mathematical dependency between the hardness and the elements of chemical composition – the basic elements (Carbon [C], Manganese [Mn] and Silicon [Si]), the particulate elements (Sulphur [S], Phosphorus [P] and Magnesium [Mg]) and the main alloying elements (Nickel [Ni], Molybdenum [Mo] and Chrome [Cr]). The main results and the graphical addenda are presented.

scholarly journals Influence of abrasive materials on the quality of analytical surfaces during preparation of samples for spectral analysis

2020 ◽  
pp. 112-116
Author(s):  
M. V. Lagoyskaya
Keyword(s):  
Spectral Analysis ◽  
Chemical Composition ◽  
Sample Preparation ◽  
Mass Fraction ◽  
Surface Preparation ◽  
Optical Emission ◽  
Sample Surface ◽  
Standard Samples ◽  
Materials Used

The article considers the possibility of contamination of the surface of steel samples with abrasive materials when preparing samples for determining the chemical composition on optical emission spectrometers.The standards for sample preparation methods describe in detail the methods of surface treatment, the materials used, and the requirements for the quality of the analyzed surface. The sample surface can be milled or sanded using various abrasive materials. In practice, the laboratory found that the surface of samples during sample preparation is contaminated with aluminum and calcium.In order to determine how the contamination of analytical surfaces occurs, the chemical composition of all materials used in the preparation of samples was studied, and an experiment was conducted to establish a method for preparing the sample surface that does not lead to contamination of the surface with aluminum and calcium. For the experiment, three standard samples of steel composition were selected with certified values of the mass fraction of aluminum and calcium in different ranges. The surface of each sample was processed in three ways and optical emission spectral analysis was performed on each analytical surface at five points to determine the value of the mass fraction of aluminum and calcium and to estimate the spread of the results obtained. As a result of tests it was found that by grinding the sample surface by using abrasive white corundum and abrasive paper grit P40 is the surface contamination of the analyzed sample in aluminum and calcium, therefore, when determining the mass fraction of aluminium and calcium in steel are required for surface preparation to use the method of milling.

Leguminous blocks: Nutritional values and economics

2016 ◽  
Author(s):  
P. S. Takawale ◽  
S. S. Jade ◽  
S. D. Ghorpade
Keyword(s):  
Chemical Composition ◽  
Silica Content ◽  
Research Station ◽  
Central Research ◽  
Crude Fibre ◽  
Nutritional Values ◽  
Nutritive Values ◽  
Mineral Mixture ◽  
The Cost

Present study was conducted at Central Research Station of BAIF Development Research Foundation, Urulikanchan, Pune during 2013 to 2015 with an objective to determining the nutritive values and keeping quality of legume blocks. Leaf meals were prepared from sun dried leaves and chaffed twigs of subabul (Leucaena leucocephala), desmanthus (Desmanthus vergatus), sesbania (Sesbania sesban) and lucerne (Medicago sativa). Five blocks were prepared by adding molasses, corn flour, mineral mixture and salt. Chemical composition such as dry matter (DM), crude protein (CP), crude fibre (CF), ether extract (EE), ash and silica content were determined according to standard analytical procedures. The chemical composition was more or less similar in fresh and stored legume blocks in all the recipes and did not vary much during storage. Further, no deterioration in colour, odour or texture was observed in storage, or any apparent contamination with mould. Among the five leguminous blocks, highest nutritive values in terms of CP, CF, EE, ash and silica were observed in sesbania legume block (22.17, 12.14, 3.52, 10.71 and 0.52%) followed by blocks of subabul (20.52, 10.61, 3.42, 10.72 and 0.81%) respectively. The cost of per kg production of leguminous block of subabul and sesbania was low as compared to lucerne blocks, which were Rs. 20, 21 and 29 correspondingly. All the goats offered legume blocks accepted them readily. All the blocks were offered to difeerent five goats for feeding and their acceptance and the intake was 100 per cent. Hence, the leguminous blocks prepared from sesbania and subabul leaf meal were selected as the best leguminous blocks as goat feed.

A Method for Predicting the Chemical Composition of Recycled Aluminum Alloys

2012 ◽  
Vol 576 ◽  
pp. 671-674
Author(s):  
Musbah Mahfoud ◽  
Prasad Ayyagari
Keyword(s):  
Chemical Composition ◽  
Aluminum Alloys ◽  
Present Method ◽  
Alloy Composition ◽  
Aluminum Scrap ◽  
Astm Standard ◽  
Automotive Components ◽  
Deviation Factor ◽  
Standard Alloy

The present paper describes a method for predicting the imminence (hereafter referred as ‘quality’) of the chemical composition of a recycled alloy to that of a standard alloy of aluminum recycled alloy made from aluminum scrap (used automotive components). The present method allows the chemical composition of a recycled alloy to be predicted. The method has been validated experimentally, and the results obtained showed that the composition of the recycled alloy was close to that of the predicted one. These findings indicate that the present method can be successfully used for any other recycled alloys to predict the alloy composition based on the in-coming scrap alloys. In this work, the chemical composition of a synthesized recycled alloy was compared to an ASTM standard alloy with the nearest composition. It was found that the two compositions were very comparable. A deviation factor has been defined in order to understand the quality of the recycled alloy obtained with reference to the ASTM alloy.

Parameters Of Technological Processes Reengineering

2020 ◽  
pp. 28-33
Keyword(s):  
Spatial Organization ◽  
Parametric Model ◽  
Practical Significance ◽  
Machine Time ◽  
Time Machine ◽  
Technological Processes ◽  
Technical Capability ◽  
Materials Used ◽  
The Cost ◽  
Qualitative Characteristics

The article is devoted to reengineering of technological processes - a method of their qualitative transformation on an innovative basis, which in turn assumes the availability of tools that make it possible to establish the economic efficiency and technical capability of such transformations of construction production, to identify the effect of their implementation. In this regard, the problem of forming a parametric model of reengineering of construction technological processes, which involves four enlarged groups of indicators that reflect the quantitative and qualitative characteristics of the processes: materials used, working time, machine time, spatial organization, is considered. It is established that parameters can have either an absolute (physical, cost) or relative (point, percentage) expression and also make their own decomposition. The practical significance of the provisions given in the article is determined by the development of methods of technical rationing, which leads to a reduction in the cost and duration of construction.

Sign in / Sign up

Export Citation Format

Share Document