scholarly journals Reception Ferrotungsten from Wolframite Concentrate by Alumimotermic Method

2011 ◽  
Vol 13 (3-4) ◽  
pp. 205
Author(s):  
N.Yu. Golovchenko ◽  
O.S. Bairakova ◽  
G.I. Ksandopulo ◽  
S.Kh. Aknazarov
Keyword(s):  
Positive Impact ◽  
Raw Materials ◽  
Combustion Process ◽  
Metal Extraction ◽  
High Melting Point ◽  
X Ray ◽  
Smooth Flow ◽  
Master Alloys ◽  
Warm Additives ◽  
Selection Of

For the smelting ferrotungsten of raw materials (mineral) took us to calculate the charge for each experiment. To optimize the process of obtaining ferrotungsten of wolframite carried out the following activities: to reduce speed and combustion temperature. A change batch positive impact on the development of the combustion process. Experimental results have shown the effectiveness of the introduction of aluminium additives in excess of stoichiometry because the explosive burning regime turned into stationary. In this work the charge calculated on 300 g volframite concentrate so that as a result of the aluminotermic reaction in the alloy contained 70% of tungsten. Calculations of charge showed that in the case of the smelting of ferro-alloys and master alloys used in this work and have a high melting point (ferrotungsten, ferromolybdenum, etc.) – temperature process of melting alloy is indispensable for the success of melting. To reduce the speed of combustion and the temperature were conducted experiments on selection of ballast additives which allows you to bring the process to a smooth flow of the reaction. As ballast additives used aluminium oxide. It was found that an increase of more than 20 additives reducing the release of the alloy and metal extraction. Also included experiments on selection of warm additives. Use as a warm additive of ammonium nitrate is not desirable because of the rapid reaction and loss of metal slag. The output and the extraction of metal in the application of potassium and sodium nitrate are the same but in the case of kalievoj nitrate slag can be used as a prolonged potash fertilizer. From the x-ray spectrometer alloys were analyzed.

scholarly journals Effect of Harvest Season on the Fuel Properties of Sida hermaphrodita (L.) Rusby Biomass as Solid Biofuel

Energies ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 3398 ◽  
Author(s):  
Nikola Bilandžija ◽  
Tajana Krička ◽  
Ana Matin ◽  
Josip Leto ◽  
Mateja Grubor
Keyword(s):  
Positive Impact ◽  
Raw Materials ◽  
Cell Structure ◽  
Combustion Process ◽  
Electric Energy ◽  
Energy Crops ◽  
Fuel Properties ◽  
Biomass Combustion ◽  
Solid Biofuel ◽  
Combustion Processes

Biomass obtained from cultivated energy crops is one of the raw materials with the highest potential in renewable energy production. Although such biomass can be used in production of lignocellulose bioethanol, it is currently mostly used as solid fuel for generating heat and/or electric energy via combustion processes. Calorific values, proximate and ultimate analysis, cell structure and micro- and macro-elements data are considered as basic parameters in the valorization of fuel properties during biomass combustion processes. Energy crops are cultivated with the aim to produce the largest possible quantity of biomass with minimal agro-technical inputs. One of these crops is Sida hermaphrodita (L.) Rusby. Given the fact that the chemical composition of biomass is influenced by a number of agro-ecological and agro-technical factors, the aim of this work was to determine the fuel properties of Sida hermaphrodita biomass obtained from three different harvest seasons (autumn, winter and spring) and cultivated in the area of the Republic of Croatia. On the basis of these investigations it was possible to conclude that harvest delaying towards spring season had a positive impact on suitability of using biomass of Sida hermaphrodita in the combustion process, which primarily means significant lowering the contents of moisture (18.64%), ash (1.94%), and nitrogen (0.65%), but also means increasing the contents of fixed carbon (6.21%) and lignin (25.45%).

scholarly journals PEMILIHAN SUPPLIER BERDASARKAN INDEKS KAPABILITAS DENGAN KARAKTERISTIK TUNGGAL

2018 ◽  
Vol 1 (2) ◽  
pp. 202-208
Author(s):  
Erik Bagus Prasetyo
Keyword(s):  
Production Process ◽  
Supplier Selection ◽  
Selection Criteria ◽  
Positive Impact ◽  
Raw Materials ◽  
Manufacturing Companies ◽  
Color Degradation ◽  
Ph Level ◽  
Selection Of

Raw materials is a major requirement in the production process for manufacturing companies. in fulfilling the needs of raw materials for the production process, most manufacturing firms depends on suppliers. Supplier selection is an important part of manufacturing companies. From several supplier selection criteria, quality is one of the important criteria and it used in supplier assessment. Selecting suppliers based on the quality of their products will have a positive impact on manufacturing companies, such as increased profits through reduced operational costs and increased market share. In this study will compare two suppliers at manufacturing companies and choose one that has a higher capability value. The selection of suppliers is made using the yield index of Spk with a single characteristic. Supplier will be selected by comparing the yield ratio of two suppliers. Numerical calculations are performed on suppliers based on pH levels on the leather. The pH level on the leather will affect the color. A low pH may result color degradation earlier, whereas a high pH may result poor color matching.

scholarly journals Composition data of a large collection of black-appearing Roman glass

2013 ◽  
Vol 1 (1) ◽  
pp. 22 ◽  
Author(s):  
Simone Cagno ◽  
Peter Cosyns ◽  
Veerle Van der Linden ◽  
Olivier Schalm ◽  
Andrei Izmer ◽  
...  
Keyword(s):  
Roman Empire ◽  
Raw Materials ◽  
Glass Production ◽  
Acrylic Resin ◽  
X Ray ◽  
Flat Surfaces ◽  
Inductively Coupled ◽  
Roman Glass ◽  
Compositional Changes ◽  
Selection Of

Jewels and tableware made of black-appearing glass were popular in the Roman Empire. Compositional changes (due to modifications in glassmaking technology and use of raw materials) over the period considered (1st-5th century AD) have been investigated on a large number of samples originating from various archaeological excavations in Europe, Northern Africa and the Near East. In the course of this work, over 400 samples of Roman glass, the greatest part of them deeply coloured glass fragments, were embedded into acrylic resin and mechanically ground and polished in order to obtain flat surfaces of unaltered glass. The samples were analysed with scanning electron microscopy/energy dispersive X-ray spectroscopy and the quantification was performed by using a standard-less ZAF software. The trace elements contained in a selection of glass samples were determined via laser ablation-inductively coupled plasmamass spectrometry. The data collected in this study show that from about 150 AD a change in the black glass production process occurred, involving coloration of raw glass made with iron in the secondary workshops. Furthermore, from the 4th century AD on we can observe a change in the type of raw glass used, while the colouring process was maintained. The main aim of this paper is to provide glass scholars with the analysis results, as reference and comparison for further studies.

DOES FOREIGN DIRECT INVESTMENT IMPROVE ECONOMIC GROWTH IN CEMAC COUNTRIES?

2013 ◽  
Vol 8 (2) ◽  
Author(s):  
EMMANUEL BRUNO  ONGO NKOA
Keyword(s):  
Economic Growth ◽  
Positive Impact ◽  
Raw Materials ◽  
Research Work ◽  
Growth Theory ◽  
The Past ◽  
The Impact ◽  
Neoclassical Growth Theory ◽  
Neoclassical Growth ◽  
Selection Of

The aim of this research work is to assess the influence of FDI on economic growth in the CEMAC region. The ratio of FDIs in the actual GDP of countries of the CEMAC region has recorded a steady annual increase for the past three decades. Moreover, the high variability of FDI, given the various crises and fluctuations in the prices of raw materials invites us to reflect and question the impact of FDI on growth by studying the case of CEMAC countries. The theoretical analysis is based on the neoclassical growth theory and its extensions. After the selection of a model crafted from Imoudu (2012) and Boreinsztein et al. (1998). The results show that FDI have a positive impact on the growth of the sub-region and these are conveyed by human capital.

BÖHLER W403 VMR

Alloy Digest ◽  
2013 ◽  
Vol 62 (9) ◽  
Keyword(s):  
Heat Treatment ◽  
Chemical Composition ◽  
Physical Properties ◽  
Tool Steel ◽  
Raw Materials ◽  
Heat Treating ◽  
Diffusion Annealing ◽  
Selection Of

Abstract Böhler (or Boehler) W403 VMR is a tool steel with outstanding properties, based not only on a modified chemical composition, but on the selection of highly clean raw materials for melting, remelting under vacuum (VMF), optimized diffusion annealing, and a special heat treatment. This datasheet provides information on composition, physical properties, and elasticity. It also includes information on forming and heat treating. Filing Code: TS-721. Producer or source: Böhler Edelstahl GmbH.

Usability of field X-ray fluorescence analyzers for determination of the chemistry of cement raw materials - using an example of Mokrá Quarry

2016 ◽  
Author(s):  
Jiří Zimák ◽  
Kristýna Dalajková ◽  
Roman Donocik ◽  
Petr Krist ◽  
Daniel Reif ◽  
...  
Keyword(s):  
Raw Materials ◽  
X Ray

scholarly journals Waste and Solar Energy: An Eco-Friendly Way for Glass Melting

2021 ◽  
Vol 5 (2) ◽  
pp. 16
Author(s):  
Isabel Padilla ◽  
Maximina Romero ◽  
José I. Robla ◽  
Aurora López-Delgado
Keyword(s):  
Solar Energy ◽  
Environmental Sustainability ◽  
Raw Materials ◽  
Glass Melting ◽  
Glass Network ◽  
X Ray Diffraction ◽  
X Ray ◽  
Concentrated Solar Energy ◽  
Calcium Source ◽  
The Aluminum Industry

In this work, concentrated solar energy (CSE) was applied to an energy-intensive process such as the vitrification of waste with the aim of manufacturing glasses. Different types of waste were used as raw materials: a hazardous waste from the aluminum industry as aluminum source; two residues from the food industry (eggshell and mussel shell) and dolomite ore as calcium source; quartz sand was also employed as glass network former. The use of CSE allowed obtaining glasses in the SiO2-Al2O3-CaO system at exposure time as short as 15 min. The raw materials, their mixtures, and the resulting glasses were characterized by means of X-ray fluorescence, X-ray diffraction, and differential thermal analysis. The feasibility of combining a renewable energy, as solar energy and different waste for the manufacture of glasses, would highly contribute to circular economy and environmental sustainability.

scholarly journals Mining Wastes of an Albite Deposit as Raw Materials for Vitrified Mullite Ceramics

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 232
Author(s):  
Pedro J. Sánchez-Soto ◽  
Eduardo Garzón ◽  
Luis Pérez-Villarejo ◽  
George N. Angelopoulos ◽  
Dolores Eliche-Quesada
Keyword(s):  
Particle Size ◽  
Raw Materials ◽  
Phase Evolution ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Mining Wastes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Maximum Value

In this work, an examination of mining wastes of an albite deposit in south Spain was carried out using X-ray Fluorescence (XRF), X-ray diffraction (XRD), particle size analysis, thermo-dilatometry and Differential Thermal Analysis (DTA) and Thermogravimetric (TG) analysis, followed by the determination of the main ceramic properties. The albite content in two selected samples was high (65–40 wt. %), accompanied by quartz (25–40 wt. %) and other minor minerals identified by XRD, mainly kaolinite, in agreement with the high content of silica and alumina determined by XRF. The content of Na2O was in the range 5.44–3.09 wt. %, being associated with albite. The iron content was very low (<0.75 wt. %). The kaolinite content in the waste was estimated from ~8 to 32 wt. %. The particle size analysis indicated values of 11–31 wt. % of particles <63 µm. The ceramic properties of fired samples (1000–1350 °C) showed progressive shrinkage by the thermal effect, with water absorption and open porosity almost at zero at 1200–1250 °C. At 1200 °C, the bulk density reached a maximum value of 2.38 g/cm3. An abrupt change in the phase evolution by XRD was found from 1150 to 1200 °C, with the disappearance of albite by melting in accordance with the predictions of the phase diagram SiO2-Al2O3-Na2O and the system albite-quartz. These fired materials contained as main crystalline phases quartz and mullite. Quartz was present in the raw samples and mullite was formed by decomposition of kaolinite. The observation of mullite forming needle-shape crystals was revealed by Scanning Electron Microscopy (SEM). The formation of fully densified and vitrified mullite materials by firing treatments was demonstrated.

Pediatric Minor Head Trauma: Factors Affecting the Anxiety of Parents

2021 ◽  
pp. 000992282110096
Author(s):  
Hasan Aldinc ◽  
Cem Gun ◽  
Serpil Yaylaci ◽  
Erol Barbur
Keyword(s):  
Computed Tomography ◽  
Head Trauma ◽  
Pediatric Patients ◽  
Positive Impact ◽  
Cranial Computed Tomography ◽  
Sufficient Information ◽  
Minor Head Trauma ◽  
Computed Tomography Imaging ◽  
Factors Affecting ◽  
X Ray

Managing the anxiety of the parents of pediatric patients with head trauma is challenging. This study aimed to examine the factors that affect anxiety levels of parents whose children were admitted to the emergency department with minor head trauma. In this prospective study, the parents of 663 consecutive pediatric patients were invited to answer a questionnaire. Parents of 600 children participated in the study. The parents who believed they were provided sufficient information and who were satisfied with the service received had significantly more improvement in anxiety-related questions. Cranial X-ray assessment had a significantly positive impact on the anxiety of the parents, whereas cranial computed tomography and neurosurgery consultation did not. In assessing pediatric minor head trauma, cranial computed tomography imaging and neurosurgery consultation should not be expected to relieve the anxiety of the parents. However, adequately informing them and providing satisfaction are the factors that could lead to improvement.

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