scholarly journals Evaluation of ground pollution by hydrocarbons using Rock-Eval pyrolysis

2019 ◽  
Vol 21 (3) ◽  
pp. 8-12
Author(s):  
Dariusz Więcław ◽  
Maria Sadlik

Abstract The exploration and utilization of petroleum are potential hazards to the environment. Successful determination of petroleum contamination in ground relies on accurate definition of the type, source and quantity of contaminant. For this purpose the Rock-Eval® pyrolysis was applied, which is a rapid quantitative (Bulk Rock method) and qualitative (fractional composition using Multi-Heating Rates method) technique. Results of Rock-Eval analysis of 13 samples of concrete and 2 samples of gravel taken from the different sites of the petrol station indicate the highest concentration of light hydrocarbons (gasoline and naphtha fractions), up to over 5% wt. in the direct proximity of petrol pumps. Similarly high contamination (almost 4%wt.), was found near fuel tanks. Here the highest contribution has lubricating oil fraction and the tankers providing fuels are probably the source of this pollution. In the gravel collected in the vicinity of the fuel tanks high concentration (over 5 wt.%) of non-pyrolyzable carbon (soot) was recorded, the source of which are probably diesel engines of fuel tankers supplying fuel.

1984 ◽  
Vol 2 (2) ◽  
pp. 118-123 ◽  
Author(s):  
J P Dutcher ◽  
P J Haney ◽  
N O Whitley ◽  
R Finley ◽  
P Pearl ◽  
...  

Six patients with biopsy-proven hepatoma were prospectively evaluated both by conventional computed tomography (CT) and by scans using ethiodized oil emulsion 13 (EOE 13) as a contrast agent. EOE 13 infusion resulted in marked improvement in the demonstration of the neoplasm in all cases and allowed more accurate definition of tumor extent than was possible with standard scanning techniques. In two cases EOE 13 enhancement was essential for complete radiographic depiction of tumor location, size, and extent. EOE 13 also proved to be of considerable value in assessment of therapeutic response in three patients, permitting more objective determination of tumor growth or regression. EOE 13--enhanced CT scanning provides a valuable means of staging patients presenting with hepatoma and is a reliable, accurate means of radiographic follow-up.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Irene A. Abela ◽  
Chloé Pasin ◽  
Magdalena Schwarzmüller ◽  
Selina Epp ◽  
Michèle E. Sickmann ◽  
...  

AbstractDetermination of SARS-CoV-2 antibody responses in the context of pre-existing immunity to circulating human coronavirus (HCoV) is critical for understanding protective immunity. Here we perform a multifactorial analysis of SARS-CoV-2 and HCoV antibody responses in pre-pandemic (N = 825) and SARS-CoV-2-infected donors (N = 389) using a custom-designed multiplex ABCORA assay. ABCORA seroprofiling, when combined with computational modeling, enables accurate definition of SARS-CoV-2 seroconversion and prediction of neutralization activity, and reveals intriguing interrelations with HCoV immunity. Specifically, higher HCoV antibody levels in SARS-CoV-2-negative donors suggest that pre-existing HCoV immunity may provide protection against SARS-CoV-2 acquisition. In those infected, higher HCoV activity is associated with elevated SARS-CoV-2 responses, indicating cross-stimulation. Most importantly, HCoV immunity may impact disease severity, as patients with high HCoV reactivity are less likely to require hospitalization. Collectively, our results suggest that HCoV immunity may promote rapid development of SARS-CoV-2-specific immunity, thereby underscoring the importance of exploring cross-protective responses for comprehensive coronavirus prevention.


2006 ◽  
Vol 39 (6) ◽  
pp. 812-825 ◽  
Author(s):  
J. R. Santisteban ◽  
M. R. Daymond ◽  
J. A. James ◽  
L. Edwards

ENGIN-X, a new time-of-flight (TOF) neutron diffractometer optimized to measure elastic strains at precise locations in bulky specimens recently commissioned at the ISIS Facility in the Rutherford Laboratory, UK, is described. Fast counting times, together with a flexible and accurate definition of the instrumental gauge volume are the main requirements of neutron strain scanning and have been addressed on ENGIN-X through the design of a novel TOF diffractometer with a tuneable resolution and interchangeable radial collimators. Further, the routine operation of the instrument has been optimized by creating a virtual instrument,i.e.a three-dimensional computer representation of the diffractometer and samples, which assists in the planning and execution of experiments. On comparing ENGIN-X with its predecessor ENGIN, a 25× gain in performance is found, which has allowed the determination of stresses up to 60 mm deep in steel specimens. For comparison with constant-wavelength diffractometers, special attention has been paid to the absolute number of counts recorded during the experiments. A simple expression is presented for the estimation of counting times in TOF neutron strain scanning experiments.


1991 ◽  
Vol 22 ◽  
pp. S459-S462 ◽  
Author(s):  
G.E. Andrews ◽  
M.K. Abbass ◽  
S. Abdul Haleem ◽  
Y. Shen ◽  
P.T. Williams ◽  
...  
Keyword(s):  

Author(s):  
Michael T. Postek

The term ultimate resolution or resolving power is the very best performance that can be obtained from a scanning electron microscope (SEM) given the optimum instrumental conditions and sample. However, as it relates to SEM users, the conventional definitions of this figure are ambiguous. The numbers quoted for the resolution of an instrument are not only theoretically derived, but are also verified through the direct measurement of images on micrographs. However, the samples commonly used for this purpose are specifically optimized for the measurement of instrument resolution and are most often not typical of the sample used in practical applications.SEM RESOLUTION. Some instruments resolve better than others either due to engineering design or other reasons. There is no definitively accurate definition of how to quantify instrument resolution and its measurement in the SEM.


Author(s):  
Carlos Ortiz de Landázuri

Heidegger, Zubiri, Apel y Polo habrían propuesto una definición más correcta de las respectivas nociones de sujeto relacional humano, a saber: “Dasein” o “ser-ahí”; “personeidad” o “esencia abierta”; “intersubjetividad” o “la llamada por parte de los entes a diversos interlocutores”; y, finalmente, “persona-núcleo” o “agente mediador entre los entes y el ser”. Se pretendía así evitar una vuelta a las paradojas del “sujeto transcendental” en Kant, del “yo absoluto” en Hegel o del “sujeto fenomenológico” en Husserl. Sin embargo en cada caso se siguieron estrategias heurísticas específicamente distintas a la hora de conceptualizar dicho sujeto relacional: Heidegger propuso una superación de la noción de “sujeto fenomenológico” en Husserl; Zubiri, en cambio, defendería una recuperación de la noción de “sujeto fenomenológico” en Husserl; por su parte, Apel propondría una reformulación semióticamente transformada del “Dasein” heideggeriano; finalmente, Polo propondría una reformulación gnoseológica de la noción de “Dasein” heideggeriano.Heidegger, Zubiri, Apel, and Polo have proposed a more accurate definition of the respective notions of human relational subject: “Dasein” or “being-there”; “Personhood” or “open essence”; “inter-subjectivity” or “entities’ appeal to diverse interlocutors”; and, finally, “nucleus-person” or “mediator between entities and being”. The aim is to avoid a return to Kant’s transcendental subject paradoxes and Hegel’s “absolute I” or Husserl´s “fenomenological subject”. But in each case specifically different heuristic strategies were followed when conceptualizing said relational subject: Heidegger proposed overcoming the notion of “phenomenological subject” in Husserl; Zubiri, however, defend the recovery of the notion of “phenomenological subject” in Husserl; meanwhile, Apel propose a transformed semiotically reformulation of Heidegger’s “Dasein”; finally, Polo propose a reformulation of the epistemological notion of Heidegger’s “Dasein”.


2016 ◽  
Vol 4 (2) ◽  
pp. 170 ◽  
Author(s):  
K. Eylem Özkaya Lassalle

The concept of failed state came to the fore with the end of the Cold War, the collapse of the USSR and the disintegration of Yugoslavia. Political violence is central in these discussions on the definition of the concept or the determination of its dimensions (indicators). Specifically, the level of political violence, the type of political violence and intensity of political violence has been broached in the literature. An effective classification of political violence can lead us to a better understanding of state failure phenomenon. By using Tilly’s classification of collective violence which is based on extent of coordination among violent actors and salience of short-run damage, the role played by political violence in state failure can be understood clearly. In order to do this, two recent cases, Iraq and Syria will be examined.


2020 ◽  
Vol 2020 (9) ◽  
pp. 29-33
Author(s):  
Sergey Bulatov

The paper purpose is the effectiveness estimation in the technological equipment use, taking into account its reliability and productivity for defective transmission units of buses. The problem consists in the determination of time to be spent on repair of bus transmission units taking into account technological equipment reliability. In the paper there is used a probabilistic method for the prediction bus transmission units, and also a method of the dynamics of averages which allow ensuring minimum of costs for units downtime during repair and equipment cost. The need for repair of transmission units (gear box) arises on an average after 650 hours, the average productivity of the bench makes 4.2 bus / hour. The bench fails on the average after 4600 hours of work, the average time of the bench makes 2 hours. In such a way the solution of the problem specified allows analyzing the necessity of time decrease for transmission unit repair to avoid long downtimes of buses in repair areas without negative impact upon high repair quality and safety during the further operation.


2020 ◽  
pp. 28-32
Author(s):  
V.S. Vanaev

Development of complex determination of parameters of jackhammers at bench tests is studied. The modern support of tests of jackhammers for the purpose of definition of their energy, vibration and noise indicators is considered. Descriptions of the SORP universal bench and UIPU measuring complex are given. Keywords jackhammer, bench, tests, processing object, energy indicators, impact energy, dynamic indicators [email protected]


2017 ◽  
Vol 31 (2) ◽  
pp. 156-162 ◽  
Author(s):  
O. V. Schneider

The article summarizes the main approaches in the definition of business valuation the economic entity. In the process of business valuation, taking into account the risks of financial and economic activities necessary to obtain information on what stage the owner implements the business will receive income. The most difficult task is the impossibility of accurate prediction in determining the level of income and the determination of a discount rate capitalization of future incomes due to the instability of the economy, both in the country and around the world.


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