scholarly journals Study on Sulfide Oxidation in a Clay Matrix by the Hyphenated Method

Minerals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1121
Author(s):  
Eulalia Zumaquero ◽  
Jessica Gilabert ◽  
Eva María Díaz-Canales ◽  
María Fernanda Gazulla ◽  
María Pilar Gómez-Tena

The requirement of a ceramic product with high technical and aesthetic performance makes it necessary to select and control raw materials to avoid losses caused by low-quality products. Many defects have their origin in impurities present in clay minerals such as sulfides and sulfates. It is important to study the oxidation, decomposition, and pyrolysis reactions that affect these minerals and their dependence on environment conditions (humidity and temperature) during the extraction and beneficiation of clay minerals in an open pit mine. The development of hyphenated techniques coupling mass spectrometry with a thermal analysis instrument provides information that is not available from either technique alone, such as decomposition behavior and the determination of emissions with a lower limit of detection. The evolution of sulfur dioxide from the oxidation of different sulfides provides information on the in situ oxidation and decomposition reactions that happen when a thermal treatment is applied. The results obtained show important differences in the reactions that take place in sulfides when they are stored under different environmental conditions. Specifically, the general tendency is that the sulfurs stored under high relative humidity show a decrease in the intensity of the emission as well as changes in the onset of the peak emission.

DYNA ◽  
2020 ◽  
Vol 87 (213) ◽  
pp. 116-122
Author(s):  
Iván Supelano García ◽  
Carlos Andrés Palacio Gómez ◽  
Julieth Alexandra Mejía Gómez ◽  
Carlos Arturo Parra Vargas

An adequate identification of physico-chemical properties of clay minerals is an important step to develop technological applications. In Colombia, a common issue is that the evaluation of raw materials with the preparation of the final product depend on empirical knowledge, it is common not to use any kind of technological tool to conduct any analysis. In contrast, the clay mixtures for this study were prepared and characterized by following a careful procedure to evaluate and control the qualities such as color of the final product. For this purpose, differential scanning calorimetry, magnetization, scanning electron microscopy, X-rays analysis, and positron annihilation lifetime spectroscopy techniques were applied. It is possible to conclude that the implementation scientific techniques in the sector of clay minerals may serve as a powerful tool, since preparing samples in an empirical way have been proved to lead to different qualities in the final product.


Author(s):  
V. V. Agafonov ◽  
V. Yu. Zalyadinov ◽  
M. E. Yusupov ◽  
N. S. Bikteeva

Sustainability of mining companies is of of high concern. The problem is specifically acute at companies that are monotownor monosettlement-forming. Sustainability of a mine depends in many ways on product quality and production resource-intensity. This article discusses formation of mineral quality indexes in terms of an open pit chrysotile mine. The studies took into account specific features of operation procedures implemented by each structural division of the mine. The analysis has found managerial and technological inconsistencies which affect quality and marketable product output, as well as efficiency of the mine in whole. The background for efficiency enhancement at a company is, by the authors’ opinion, consolidation of personnel subject to the single development strategy, namely: improvement of production and control efficiency, as well as use of available reserves and resources by means of better setup for production. The proposed approaches to planning mining operations and forming mineral quality allow higher quality of processing stock. In addition, a new model proposed for interaction between structural divisions of a mining company ensures improvement of general production indexes.


Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1399
Author(s):  
Karina Yévenes ◽  
Ekaterina Pokrant ◽  
Lina Trincado ◽  
Lisette Lapierre ◽  
Nicolás Galarce ◽  
...  

Tetracyclines, sulphonamides, and quinolones are families of antimicrobials (AMs) widely used in the poultry industry and can excrete up to 90% of AMs administrated, which accumulate in poultry litter. Worryingly, poultry litter is widely used as an agriculture fertilizer, contributing to the spread AMs residues in the environment. The aim of this research was to develop a method that could simultaneously identify and quantify three AMs families in poultry litter by high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS). Samples of AMs free poultry litter were used to validate the method according to 657/2002/EC and VICH GL49. Results indicate that limit of detection (LOD) ranged from 8.95 to 20.86 μg kg−1, while limits of quantitation (LOQ) values were between 26.85 and 62.58 µg kg−1 of tetracycline, 4-epi-tetracycline, oxytetracycline, 4-epi-oxytetracycline, enrofloxacin, ciprofloxacin, flumequine, sulfachloropyridazine, and sulfadiazine. Recoveries obtained ranged from 93 to 108%. The analysis of field samples obtained from seven commercial poultry flocks confirmed the adequacy of the method since it detected means concentrations ranging from 20 to 10,364 μg kg−1. This provides us an accurate and reliable tool to monitor AMs residues in poultry litter and control its use as agricultural fertilizer.


Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1577
Author(s):  
Klaudia Kotecka-Majchrzak ◽  
Natalia Kasałka-Czarna ◽  
Agata Sumara ◽  
Emilia Fornal ◽  
Magdalena Montowska

Consumer demand for both plant products and meat products enriched with plant raw materials is constantly increasing. Therefore, new versatile and reliable methods are needed to find and combat fraudulent practices in processed foods. The objective of this study was to identify oilseed species-specific peptide markers and meat-specific markers that were resistant to processing, for multispecies authentication of different meat and vegan food products using the proteomic LC-MS/MS method. To assess the limit of detection (LOD) for hemp proteins, cooked meatballs consisting of three meat species and hemp cake at a final concentration of up to 7.4% were examined. Hemp addition at a low concentration of below 1% was detected. The LOD for edestin subunits and albumin was 0.9% (w/w), whereas for 7S vicilin-like protein it was 4.2% (w/w). Specific heat-stable peptides unique to hemp seeds, flaxseed, nigella, pumpkin, sesame, and sunflower seeds, as well as guinea fowl, rabbit, pork, and chicken meat, were detected in different meat and vegan foods. Most of the oilseed-specific peptides were identified as processing-resistant markers belonging to 11S globulin subunits, namely conlinin, edestin, helianthinin, pumpkin vicilin-like or late embryogenesis proteins, and sesame legumin-like as well as 2S albumins and oleosin isoforms or selected enzymic proteins.


2005 ◽  
Vol 34 (4) ◽  
pp. 243-248
Author(s):  
L. Pinotti ◽  
V.M. Moretti ◽  
A. Baldi ◽  
F. Bellagamba ◽  
A. Campagnoli ◽  
...  

The protracted outbreak of mad-cow disease, repeated episodes of dioxin and mycotoxin contamination, and the issue of labelling genetically modified foods have severely shaken public confidence in the food supply industry, increasing consumer concerns about the origins of the raw materials used in both animal feed and food products. The need to develop improved techniques to characterize feed and food components has consequently become more urgent, and DNA-based technologies promise to be able to meet these needs. DNA methods can establish the origin of species in meat- and fish-based products and feed ingredients, and are the most reliable analytical approaches for authenticating processed foodstuffs. The identification of ingredients in processed feed and food is mandatory not only to ensure correct labelling and assessment of value, but also to avoid health risks related to the presence of toxic contaminants or pathogenic agents.


2021 ◽  
Vol 1023 ◽  
pp. 155-162
Author(s):  
Berenice Zúñiga-Torres ◽  
Ramiro Correa-Jaramillo ◽  
Francisco Hernández-Olivares ◽  
Francisco Fernandez-Martinez ◽  
Alonso Zúñiga-Suárez ◽  
...  

The construction industry has focused on trying to minimize and control the environmental impacts caused within the process of production and manufacture of fired bricks, for this reason the present research proposes five different alternative mixtures for the elaboration of ecological bricks, four of these based on soil-cement and one obtained through a geopolymerization process, using raw materials from the amazon region and the southern highlands of Ecuador, such as soil from the Centza mine (MC), sand from the Quiringue mine (MQ), organic correctors of husk rice (RH ), peanut shell (PS), natural gypsum (G) from the Malacatos sector and fired brick residues from the same sector. The raw materials were characterized (analysis: physicochemical and mineralogical); the soil-cement-based combinations used different percentages of substitution of organic correctors and gypsum, the optimum percentage of water and cement was determined through the compaction test and resistance to simple compression respectively, the samples were cured and tested at ages of 7, 14 and 28 days. In the geopolymerization process, an alkaline solution NaOH was used in different concentrations of molarity and solution contents, the specimens were cured at temperatures of 90 °C, 120 °C, 150 °C, 180 °C and 200 °C. The different combinations were subjected to indirect traction with the purpose to determine the optimal mixture and subsequent estimation of the compressive strength of bricks applying the Griffith criterion, the results were validated by the finite element method, obtaining strengths of 4 MPa in the combination soil-cement sand (SC_Ar1), in soil-cement rice husk (SC_RH2) and soil-cement peanut shell (SC_PS2) mixtures its resistance is 3 MPa, while in the soil-cement gypsum (SC_G4) mixture the resistance is 6.90 MPa and finally the resistance in geopolymeric mixture (GBW) is 13.75 MPa; In this way, the optimal combinations comply and increase the resistance to simple compression of bricks by 35% the SC_Ar1 mixture, 130% in the SC_G mixture with respect to the spanish standard and 129% the GBW mixture with respect to the ecuadorian standard.


2014 ◽  
Vol 32 (5) ◽  
pp. 397-405
Author(s):  
Md. Obaidul Haque ◽  
Ahmed Sharif

Informal incineration or open pit burning of waste materials is a common practice in the peripheral area of Dhaka, one of the fastest growing mega-cities in the world. This study deals with the effect of open pit burned (i.e. open burned) household waste bottom ash on fired clay bricks. Between 0 to 50% (by weight) of open pit burned household waste bottom ash was mixed with clay to make bricks. The molded specimens were air-dried at room temperature for 24 h and then oven dried at 100 °C for another 24 h to remove the water. The raw bricks were fired in a muffle furnace to a designated temperature (800, 900 and 1000 °C, respectively). The firing behaviour (mechanical strength, water absorption and shrinkage) was determined. The microstructures, phase compositions and leachates were evaluated for bricks manufactured at different firing temperatures. These results demonstrate that open pit burned ash can be recycled in clay bricks. This study also presents physical observations of the incinerated ash particles and determination of the chemical compositions of the raw materials by wet analysis. Open pit burned ash can be introduced easily into bricks up to 20% wt. The concentrations of hazardous components in the leachates were below the standard threshold for inert waste category landfill and their environmental risk during their use-life step can be considered negligible.


Author(s):  
Mira Meirawaty ◽  
Christin Palit ◽  
Dyah Ayu Setyorini ◽  
Moehammad Ali Jambak

Utilization of Crude Palm Oil (Crude Palm Oil) in food cooking activities is a strong activity in Indonesian society, more than 80% of household activities use this type of oil to process food ingredients. The affordable price with a variety of packaging makes this type of cooking oil has many fans. A survey that has been conducted on residents of the Kalideres area with a total of 20 respondents stated that in addition to using new palm cooking oil in cooking activities, the majority of residents are also accustomed to using this oil used in cooking activities that require the deep-fried method. The quality of cooking oil is largely determined by the level of purity of the solution, the clearer the color of the solution, the better the quality, the darker the color of the solution indicates the presence of more impurities, the higher the saturated fatty acid emulsion, indicating poor cooking oil quality. This is what was raised in this community service (CS) activity, namely socializing alternatives to the use of purified bulk cooking oil. The purification material uses bentonite clay minerals which are heated and dissolved in a certain amount and duration of time which is able to maximize the adsorption power of impurities according to the natural structure of bentonite. CS activities carried out online include counseling and training activities for housewives in the economically densely populated Kalideres area. Through the socialization program for the purification of bulk cooking oil using bentonite clay minerals, it is hoped that residents will have an alternative to reduce the cost of processing food raw materials in a more effective and healthy way. This program is also expected to function as a medium to socialize the application of earth science in helping activities of daily living.


2008 ◽  
Vol 53 (1) ◽  
pp. 45-51
Author(s):  
Jasmina Lilic ◽  
Miroslav Grujic ◽  
Vesna Filipovic ◽  
Miodrag Zikic ◽  
Sasa Stojadinovic

Copper ore is one of the most important raw materials for industrial production. Increasing demands have been increasing its extraction generally. Shallow deposits with higher copper grade are mostly exhausted and the open pits become deeper, also the amount of overburden and the problems of its disposal are increased. In some cases large quantities of overburden can solve the problem of recultivation of degraded areas. This is the case of recultivation of degraded areas on the location of the closed open pit Bor. Here, the overburden from another open pit, Veliki Krivelj, is disposed into the cavity of the open pit Bor. In this way the overburden is disposed without further area degradation and the cavity is primarily, technically recultivated. When the filling process is finished, waste depot will have a flat top at the level K+450 [2], which is above the neighboring terrain, and the slopes height will vary. This problem was not especially considered up to date, so the experiences in this field are humble. This paper intends to be the basis for further research.


Author(s):  
V. K. Kochetov ◽  
N. V. Ageeva

The procedure of traceability of finished product, the regulating actions for tracking of products, beginning from the raw materials used for production of the single-part randomly chosen consumer package of a product and ending with shipment of this product to distributing facilities and also for tracking of processing of randomly chosen raw materials are offered. The traceability system does not guarantee a complete elimination of risk from arrival to the enterprise of improper raw and other materials, but allows tracking and identifying a source of nonconformance, after receiving of problem in quality of finished product. If a source of nonconformance is raw or other materials, then the manufacturer can allocate responsibilities for damage to property to the supplier of these raw or other materials. The procedure of traceability provides carrying out of training exercises at least once a year for determination of efficiency and working capacity of the current system of traceability, and also for identification and elimination of bottlenecks. For monitor and control over the stages of a process flow on the basis of the available database were proved the critical parameters of production process of confectionery, which control will allow to receive a safe product with the set technological and end-user performances. For monitor and control over the stages of a process flow on the basis of the available database on product traceability were proved the critical parameters of production process of confectionery, which control will allow to receive a safe product with the set technological and end-user performances. The accepted system eliminates a possibility of sales of products of nonconforming quality and allows to go back from the established control procedures that promotes the productivity enhancement.


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