ARTICLE | doi:10.20944/preprints202102.0312.v1
Subject: Life Sciences, Biochemistry Keywords: raw milk stretched cheeses; lactic acid bacteria; coliform bacteria; Escherichia coli; Staphylococcus aureus; yeasts and moulds
Online: 12 February 2021 (15:26:35 CET)
To evaluate the behaviour of the relevant microbial populations during stretched cheese production, the quantitative microbiological analysis was performed during the critical steps of the preparation. The obtained data distributions proved statistically significant increases in all indicators, on average by 4.55 ± 0.64 log CFU/g of presumptive lactococci counts, 4.06 ±0.61 of lactobacilli, 1.53 ± 0.57 log CFU/g of coliforms, 2.42 ± 0.67 log CFU/g of Escherichia coli, 1.53 ± 0.75 log CFU/g of yeasts and moulds, and 0.99 ± 0.27 log CFU/g of presumptive Staphylococcus aureus, from the early stage of milk coagulation until curd ripening (0–24 h). The following steaming/stretching process caused reductions in viable counts with the most significant inactivation effect on coliform bacteria, including E. coli (-4.0 ± 1.0 log CFU/g). Total viable counts and yeasts and moulds showed 2 and almost 3 log reduction (-2.2 ± 1.1 log CFU/g and -2.6 ± 0.9 log CFU/g), respectively. The lowest decreases in presumptive S. aureus counts were estimated at the level of -1.50 ± 0.64 log CFU/g. The counts of yeasts and moulds showed the best indicatory function during the entire storage period of vacuum-packaged cheeses at 6 °C.
ARTICLE | doi:10.20944/preprints202008.0063.v1
Subject: Life Sciences, Microbiology Keywords: raw milk; microbiological safety; microbiological quality; food safety; dairy; MBS method
Online: 3 August 2020 (08:07:03 CEST)
The consumption of dairy products and the dairy industry is one of the main global agro-food sectors for size, economic importance and level of technology. Microbiological quality of pasteurized milk or other milk products is dependent on microbiological quality of raw milk. A variety of microbiological count methods is available for monitoring the hygienic quality of raw milk. Among them, the pour plate method is the official essay for counting the number of colony forming units in milk samples according to ISO 4833-1:2013. The aim of the present study is the validation of the Micro Biological Survey (MBS) method, against the reference plate count method, for the assessment of the microbiological quality of raw milk. This comparative study, performed in collaboration with the “Istituto Zooprofilattico Sperimentale del Lazio e della Toscana M. Aleandri” (IZSLT), demonstrates the accuracy of this alternative method for the determination of total viable bacterial count in cow’s raw milk. The results obtained with the MBS method highlighting its potential as a valid tool for reliable microbiological analysis in dairy industries.
ARTICLE | doi:10.20944/preprints201808.0272.v1
Subject: Life Sciences, Microbiology Keywords: Staphylococcus aureus, meat, raw milk, antibiotics; antibiotic resistance genes
Online: 15 August 2018 (13:58:11 CEST)
Background: Staphylococcus aureus (S. aureus) occasionally threatens the life of the host as a persistent pathogen even though it is normal flora of humans and animals. We characterized drug resistance in S. aureus isolated from animal carcasses and milk samples from the abattoirs and dairy farms in the Eastern Cape Province. Methods: A 1000 meat swab samples and 200 raw milk samples were collected from selected abattoirs and dairy farms in the Eastern Cape Province, South Africa. S. aureus was isolated and positively identified using biochemical tests and confirmed by molecular methods. Antibiotic susceptibility test against 14 different antibiotics was performed against all isolates. Antibiotic resistance genes were also detected. Results: Of the 1200 samples collected, 134 (11.2%) samples were positive for S. aureus. Resistance ranged from 71.6% for penicillin G to 39.2% for tetracycline. Resistance gene (blaZ) was detected in 13 (14.9%), while msrA was found in 31 (52.5%) of S. aureus isolates. Conclusions: The present result shows the potential dissemination of multidrug-resistant S. aureus strains in the dairy farms and abattoirs in the Eastern Cape. Therefore, this implies that the organism may rapidly spread through food and pose serious public health risk
ARTICLE | doi:10.20944/preprints201812.0171.v1
Subject: Engineering, Energy & Fuel Technology Keywords: 2G bioethanol, Straw, Raw material volume, Question
Online: 14 December 2018 (09:44:23 CET)
There are some controversies about 2G bioethanol and it is in need of a reliable test data in order to make a further analysis and proof. In collecting basic data from three classes of typical raw materials, such as wheat, maize stalk juice, and straw, it was found that 4.32 tons straw or 3.358 tons wheat is needed to produce 1-ton bioethanol. Using the coefficient of variation calculation and analysis method, it is able to obtain the C.V. value of straw fermentation efficiency 0.08932<0.15, indicating the fermentation technology and process of 2G bioethanol is already quite mature and reliable, without risk, and also with a raw material cost advantage. There is a problem in that the C.V. value of straw volume is 1.2648>0.95, indicating 2G bioethanol is in an extremely high-risk area. Using the straw volume calculation method, building and its costs – capital expenditure of 2G bioethanol plant is approximately seven times that of a wheat ethanol plant. This should be some of the important reasons why it is noncompetitive, extremely high price, and requiring government subsidies. Straw volume data study has caused the 2G bioethanol plant to require more cement, steel, equipment, and other materials. Thus, there are ample reasons to question the CO2 emissions and its carbon footprint of 2G bioethanol plant. Actually, the volume is not the only existing problem, it is necessary to re-evaluate and discuss the definition of 2G bioethanol and its future.
REVIEW | doi:10.20944/preprints201607.0075.v1
Online: 25 July 2016 (06:34:26 CEST)
Over the past couple of decades, Global positioning system (GPS) technology has been utilized to collect large-scale data from travel surveys. As the precise spatiotemporal characteristics of travel could be provided by GPS devices, the issues of traditional travel survey, such as misreporting and non-response, could be addressed. Considering the defects of dedicated GPS devices (e.g., need much money to buy devices, forget to take devices to collect data, limit the simple size because of the number of devices, etc.), and the phenomenon that the smartphone is becoming one of necessities of life, there is a great chance for the smartphone to replace dedicated GPS devices. Although, several general reviews have been done about smartphone-based GPS travel survey in the literature review section in some articles, a systematic review from smartphone-based GPS data collection to travel mode detection has none. The included studies were searched from six databases. The purpose of this review is to critically assess the current literature on the existing methodologies of travel mode detection based on GPS raw data collected by smartphones. Meanwhile, according to the systematic comparison among different methods from data-preprocessing to travel mode detection, this paper could carefully provide the Strengths and Weaknesses of existing methods. Furthermore, it is the crucial step to develop the methodologies and applications of GPS raw data collected by smartphones.
ARTICLE | doi:10.20944/preprints202112.0115.v2
Subject: Physical Sciences, Condensed Matter Physics Keywords: room temperature superconductivity; magnetic susceptibility; diamagnetism; raw data
Online: 31 December 2021 (10:13:20 CET)
In ref. , we pointed out that certain anomalies observed in the published data for ac magnetic susceptibility of a room temperature superconductor reported in Nature 586, 373 (2020)  would be cleared up once the measured raw data were made available. Part of the measured raw data were recently posted in arXiv:2111.15017 . Here we report the results of our analysis of these raw data and our conclusion that they are incompatible with the published data. Implications of these results to the claim that the material is a room temperature superconductor are discussed.
SHORT NOTE | doi:10.20944/preprints202112.0188.v2
Subject: Physical Sciences, Condensed Matter Physics Keywords: hydride superconductor; room temperature superconductor; pressure; diamond anvil cell; ac magnetic susceptibility; raw data; background signal; random noise
Online: 21 December 2021 (09:00:23 CET)
Room temperature superconductivity has recently been reported for a carbonaceous sulfur hydride (CSH) under high pressure by Snider et al . The paper reports sharp drops in magnetic susceptibility as a function of temperature for five different pressures, that are interpreted as signaling a superconducting transition. Here I question the validity and faithfulness of the magnetic susceptibility data presented in the paper by comparison with the measured raw data reported by two of the authors of ref. . This invalidates the assertion of the paper  that the susceptibility measurements support the case for superconductivity in this compound.
ARTICLE | doi:10.20944/preprints202010.0238.v1
Subject: Engineering, Automotive Engineering Keywords: raw materials; supply chain; logistics planning; logistics strategies
Online: 12 October 2020 (12:21:56 CEST)
Raw material logistics reflects an important aspect of global trade. Raw materials form an essential basis for society, for daily life, and range from apples to zinc. This paper addresses the analysis and optimization of supply chains of raw materials in terms of their economic viability and their sustainability. Type representatives are chosen according to annual transported quantities. Hard coal represents bulk goods, aluminum primary raw materials with medium quantities, and rare earths primary raw materials with small quantities. Their respective supply chains are analyzed and subsequently possible strategies and methods and their application are discussed. The paper shows for the first time that the selection and application of optimization priorities (e.g. profitability or sustainability) depends on the primary raw material and its integration into global production chains.
ARTICLE | doi:10.20944/preprints202109.0308.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: coltan; niobium; tantalum; critical raw materials; technological metals; mineral processing.
Online: 17 September 2021 (12:02:04 CEST)
Demand for niobium and tantalum is increasing exponentially as these are essential ingredients for the manufacture of, among others, capacitors in technological devices and ferroniobium. Mine tailings rich in such elements could constitute an important source of Nb and Ta in the future and so alleviate potential supply risks. This paper evaluates the possibility of recovering niobium and tantalum from the slags generated during the tin beneficiation process of mine tailings from the old Penouta mine, located in Spain. To do so, a simulation of the processes that would be required to beneficiate and refine both elements is carried out. After tin carbothermic reduction, the slags are sent to a hydrometallurgical process where at the end niobium oxide and tantalum oxide are obtained. Reagents, water and energy consumption, in addition to emissions, effluents and product yields are assessed. Certain factors were identified as critical, and recirculation was encouraged in the model to maximize production and minimize reagents use and wastes. With this simulation, considering 3000 production hours per year, the metal output from the tailings of the old mine could cover around 1% and 7.4% of the world annual Nb and Ta demand, respectively.
ARTICLE | doi:10.20944/preprints201812.0239.v1
Subject: Chemistry, Analytical Chemistry Keywords: gold; silver; mineral raw materials; carbonaceous shales; stripping voltammetry; graphite electrode modifiers
Online: 20 December 2018 (04:55:45 CET)
Techniques of stripping voltammetry (SV) determination of silver and gold in pyrites and carbonaceous matter were developed. The problem of quantitative transfer of the sample into the solution was solved. For this purpose, the ore matrix of carbonaceous shales was decomposed by mineral acids in autoclaves at high pressures. The element to be determined from the sample matrix was separated by extraction. Ag(I) ions from the solutions were extracted in the form of dithizonate complex in CCl4. Au(III) ions were extracted by diethyl ether. The extracts were decomposed thermally. The dry residue was dissolved in the background electrolyte, and the element was determined by the SV method. The graphite electrode (GE) impregnated with polyethylene was used as a working electrode in SV–determination of silver. SV–determination of gold was carried out using GE modified by bismuth. The limits of detection (LOD) of Ag(I) and Au(III) contents were equal to 0.016 mg L-1 and 0.0086 mg L-1, respectively. The results of SV-determination of gold and silver in standard samples, pyrites and carbonaceous shales were presented. The silver content in the pyrite was 13.6 g t-1, in carbon shale—0.34 g t-1. The concentration of gold in the pyrite ore zone "Kirovsko–Kryklinskaya" was 1.15 g t-1; in carbonaceous shales—2.66 g t-1. The obtained data were consistent with the data of atomic emission spectroscopy (AES) and inductively coupled plasma mass spectrometry (ICP—MS). The error of determination of elements by stripping voltammetry was calculated when determining the silver content of 10...6 g t-1 in pyrite and carbonaceous material, which was less than 12%, and when determining the gold content of 1...3 g t- 1 in pyrite and carbonaceous matter, which was less than 23%.
ARTICLE | doi:10.20944/preprints202202.0005.v2
Subject: Physical Sciences, Condensed Matter Physics Keywords: hydride superconductor; room temperature superconductor; pressure; ac magnetic susceptibility; raw data; background signal
Online: 4 February 2022 (10:31:10 CET)
In Ref.  Snider et al reported room temperature superconductivity in carbonaceous sulfur hydride (CSH) under high pressure. Recently the data for the temperature dependent ac magnetic susceptibility shown in figures of Ref  have appeared in the form of tables corresponding to different pressures . Here we provide an analysis of the data for a pressure of 160 GPa. This work was performed in collaboration with D. van der Marel.
ARTICLE | doi:10.20944/preprints202112.0452.v1
Subject: Mathematics & Computer Science, Other Keywords: Electrical Resistance Tomography (ERT); Raw Data Processing; Inline Swirl Separator; Geometrical Parameter Extraction
Online: 28 December 2021 (14:42:44 CET)
Electrical Resistance Tomography (ERT) has been used in the literature to monitor the gas-liquid separation. However, the image reconstruction algorithms used in the studies take a considerable amount of time to generate the tomograms, which is far above the time scales of the flow inside the inline separator and, as a consequence, the technique is not fast enough to capture all the rele-vant dynamics of the process, vital for control applications. This article proposes a new strategy based on the physics behind the measurement and simple logics to monitor the separation with a high temporal resolution by minimizing both the amount of data and the calculations required to reconstruct one frame of the flow. To demonstrate its potential, the electronics of an ERT system are used together with a high-speed camera to measure the flow inside an inline swirl separator. For the 16-electrode system used in this study, only 12 measurements are required to reconstruct the whole flow distribution with the proposed algorithm, 10x less than the minimum number of measurements of ERT (120). In terms of computational effort, the technique was shown to be 1000x faster than solving the inverse problem non-iteratively via the Gauss-Newton approach, one of the computationally cheapest techniques available. Therefore, this novel algorithm has the potential to achieve measurement speeds in the order of 104 times the ERT speed in the context of inline swirl separation, pointing to flow measurements at around 10kHz while keeping the aver-age estimation error below 6 mm in the worst case scenario.
ARTICLE | doi:10.20944/preprints202103.0266.v1
Subject: Materials Science, Biomaterials Keywords: diatomite; bio-composites; , mechanical properties; fractionation; purification of diatomaceous earth; bio-raw materials
Online: 9 March 2021 (11:44:48 CET)
The authors of this paper use an original method of diatomaceous earth fractionation, which allows for obtaining a filler with a specific particle size distribution. The method makes it possible to separate small, disintegrated and broken diatom frustules from those which maintained their original form in diatomaceous earth. The study covers a range of tests conducted to prove that such a separated diatomic fraction shows features different from the base diatomite used as an epoxy resin filler. We have examined mechanical properties of a series of diatomite/resin composites considering the weight fraction of diatoms and the parameters of the composite production process. The studied composites of Epidian 601 epoxy resin cross-linked with amine-based curing agent Z-1 contained 0 to 70% vol. of diatoms or diatomaceous earth. Samples were produced by casting into silicone moulds in vacuum degassing conditions and, alternatively, without degassing. The results have shown that the size and morphology of the filler based on diatomaceous earth affects mechanical and rheological properties of systems based on epoxy resin.
ARTICLE | doi:10.20944/preprints201712.0167.v1
Subject: Chemistry, Other Keywords: vegetable oils; emulsifiers; triglycerides; FAME; epoxidized fatty acids; glycerol; polyglycerol; PGPR; renewable raw materials
Online: 25 December 2017 (07:32:07 CET)
Oligo- and polyesters of polyglycerol and polyricinoleic acid are widely used as emulsifiers in various industries. Based on the condensation of glycerol and its oligomers with epoxidized derivatives of vegetable oils, new promising emulsifiers for oil-water systems were obtained. Complex structural and functional spectral analysis of synthesized substances showed that the main reactions leading to the formation of the desired products were the opening of epoxide cycles, the transesterification of esters and the condensation of fatty acid derivatives. The new combination of renewable raw materials is of undoubted interest for deeper vegetable oils chemical processing.
ARTICLE | doi:10.20944/preprints201908.0214.v1
Subject: Mathematics & Computer Science, Probability And Statistics Keywords: Poisson distribution; raw moments; Bell polynomials; degenerate exponential function; unsigned Stirling number of the first kind.
Online: 20 August 2019 (11:14:22 CEST)
The main purpose of this paper is to introduce and investigate degenerate Poisson distrib- ution which is a new extension of the Poisson distribution including the degenerate expo- nential function. We then provide several properties of the degenerate Poisson distribution such as the first and the second raw moments and di¤erence operator property. Moreover, we acquired the skewness and the kurtosis for the degenerate Poisson distribution. We also derive its moment generating function by which we define the degenerate Bell polynomials and give a connection for these polynomials related to the unsigned Stirling numbers of the rst kind.
REVIEW | doi:10.20944/preprints201809.0225.v1
Subject: Chemistry, Chemical Engineering Keywords: heterogeneous catalytic oxidation, gas-solid, liquid-solid, partial and total oxidation, biomass based raw materials, activation methods
Online: 13 September 2018 (02:17:55 CEST)
In this short review paper we have assembled the main characteristics of partial oxidation reactions (oxidative dehydrogenation and selective oxidation to olefins or oxygenates, as aldehydes and carboxylic acids and nitriles), as well as total oxidation, particularly for depollution, environmental issues and wastewater treatments. Both gas-solid and liquid-solid media have been considered with recent and representative examples within these fields. We have also discussed about their potential and prospective industrial applications. Particular attention has been brought to new raw materials stemming from biomass and to liquid-solid catalysts cases. This review paper also summarizes the progresses made in the use of unconventional activation methods for performing oxidation reactions, highlighting the synergy of these technologies with heterogeneous catalysis. Focus has been centered on usual catalysts activation methods but also on less usual ones, such as the use of ultrasounds, microwaves, grinding (mechanochemistry) and photo-activated processes, as well as their combined use.
REVIEW | doi:10.20944/preprints202009.0315.v1
Subject: Engineering, Industrial & Manufacturing Engineering Keywords: rubber; environmental sustainability; end-of-life tires; critical raw materials; rubber processing; disintegrator; reclaiming; devulcanisation; ozone cutting; grinding; composite material
Online: 14 September 2020 (00:29:25 CEST)
Despite the development of technologies, modern methods of disposal of end-of-life tires most often represent either the incineration in cement kilns or the destruction of tires in special landfills, showing a lack of sustainable recycling of this valuable material. The fundamental role of recycling is evident, and the development of high-efficiency processes represents a priority for the European market. Therefore, investigation of end-of-life rubber processing methods is of high importance for manufacturers and recyclers of rubber materials. In this paper, methods of processing of end-of-life tires are reviewed in order to obtain rubber crumb, which can later be used in the production of new industrial rubber goods and composite The processes of separation end-of-life tire into fractions by type of materials using mechanical processing methods along with mechanochemical and mechanical processes of processing the materials of used tires in order to obtain crumb rubber of various fractions and chemical reactivity are considered.