scholarly journals Field experience with transmission oil EP Gear Synth 150

2009 ◽  
Vol 55 (No. 1) ◽  
pp. 18-23 ◽  
Author(s):  
Z. Aleš
Keyword(s):  
Operating Time ◽  
Technical Condition ◽  
The Other ◽  
Aquatic Resources ◽  
Long Term Stability ◽  
Water Flows ◽  
Transmission Oil ◽  
Operational Tests ◽  
The Impact

The machinery operated in agriculture and forestry has been required to use less harmful vital fluids since a few years ago. These requirements are highly urged especially for the machines which are operated close to aquatic resources, water flows, fields, and in forests. Biodegradable vital fluids seem as a suitable solution from the environmental viewpoint. On the other hand, from the technical viewpoint their usage seems sort of problematic. The author started to carry out long-term stability tests of biodegradable transmission oil and mineral transmission oil used in tractor end rear boxes in the dependence on the operating time. This article pinpoints partial results of the operational tests and evaluates the impact on the technical condition of the machinery.

scholarly journals Electret Filters—From the Influence of Discharging Methods to Optimization Potential

Atmosphere ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 65
Author(s):  
Maximilian Kerner ◽  
Kilian Schmidt ◽  
Stefan Schumacher ◽  
Christof Asbach ◽  
Sergiy Antonyuk
Keyword(s):  
Fine Particles ◽  
Operating Time ◽  
Filtration Efficiency ◽  
Long Term Stability ◽  
Aerosol Filtration ◽  
Charge Decay ◽  
The One ◽  
Testing Standards ◽  
Discharge Efficiency

Electret filters are electrostatically charged nonwovens which are commonly used in aerosol filtration to remove fine particles from gases. It is known that the charge and thus also the filtration efficiency can degrade over time. Thus, many testing standards require to remove the charge by treatment with liquid isopropanol (IPA) or IPA-saturated air. However, the parameters influencing this discharge have not been completely clarified yet. The aim of this work was, on the one hand, to experimentally investigate the influence of the IPA treatment on different electret filters and, on the other hand, to show the optimization potential of electret filters with respect to efficiency and long-term stability by numerical simulations. The experiments revealed that the air permeability is a central influencing parameter. Small pores lead to a reduced discharge efficiency using liquid IPA, while both treatment methods are suitable for larger pores. The simulations showed that a homogeneous charge distribution within the filter depth is advantageous for the initial performance. In contrast, charge penetrating deeper in the filter medium delays the charge decay and thus increases the operating time, with the trade-off of a lower initial performance.

Separating the impact of oxygen and water on the long-term stability of n-channel perylene diimide thin-film transistors

2015 ◽  
Vol 26 ◽  
pp. 340-344 ◽  
Author(s):  
Ute Zschieschang ◽  
Konstantin Amsharov ◽  
Martin Jansen ◽  
Klaus Kern ◽  
Hagen Klauk ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Film Transistors ◽  
Perylene Diimide ◽  
Term Stability ◽  
Long Term Stability ◽  
The Impact

Geochemical Behaviour of Uranium in Sedimentary Formations: Insights From a Natural Analogue Study

2009 ◽  
Author(s):  
Ulrich Noseck ◽  
Vaclava Havlova ◽  
Juhani Suksi ◽  
Thomas Brasser ◽  
Radek Cervinka
Keyword(s):  
Current Knowledge ◽  
Natural Analogue ◽  
Near Surface ◽  
Co2 Partial Pressure ◽  
Long Term Stability ◽  
Reducing Conditions ◽  
Phosphate Mineral ◽  
Sedimentary System ◽  
The Impact

Groundwater data from the natural analogue site Ruprechtov have been evaluated with special emphasis on the uranium behaviour in the so-called uranium-rich clay/lignite horizon. In this horizon in-situ Eh-values in the range of −160 to −280 mV seem to be determined by the SO42−/HS− couple. Under these conditions U(IV) is expected to be the preferential redox state in solution. However, on-site measurements in groundwater from the clay/lignite horizon show only a fraction of about 20% occurring in the reduced state U(IV). Thermodynamic calculations reveal that the high CO2 partial pressure in the clay/lignite horizon can stabilise hexavalent uranium, which explains the occurrence of U(VI). The calculations also indicate that the low uranium concentrations in the range between 0.2 and 2.1μg/l are controlled by amorphous UO2 and/or the U(IV) phosphate mineral ningyoite. This confirms the findings from previous work that the uranium (IV) mineral phases are long-term stable under the reducing conditions in the clay/lignite horizon without any signatures for uranium mobilisation. It supports the current knowledge of the geological development of the site and is also another important indication for the long-term stability of the sedimentary system itself, namely of the reducing geochemical conditions in the near-surface (30m to 60 m deep) clay/lignite horizon. Further work with respect to the impact of changes in redox conditions on the uranium speciation is on the way.

Economic complexity and price competitiveness dependence: empirical evidence using panel models

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Guilherme Magacho ◽  
Rafael Ribeiro ◽  
Igor Rocha
Keyword(s):  
Exchange Rate ◽  
Generalized Method Of Moments ◽  
Output Growth ◽  
The Other ◽  
Content Type ◽  
Price Competitiveness ◽  
Economic Complexity ◽  
Other Hand ◽  
The Impact

Purpose As economies with high economic complexity and productive capabilities may easily adapt their productive structure due to product differentiation and innovation, the central variable of competitiveness for these countries is the product quality, not price. On the other hand, the price can be an important determinant of less complex countries, and hence, real exchange rate (RER) misalignments may have long-term impacts. This paper aims to empirically assess variations in the magnitude of the impact in RER misalignments on output growth subject to countries’ economic complexity. Design/methodology/approach The estimation technique used is the generalized method of moments-System estimator as this method is robust to reverse causality. Heterogeneous regressions using interaction models are undertaken to analyze to what extend promoting economic complexity can reduce price competitiveness dependence and allow countries to grow faster without relying on cost competitiveness. Findings Estimates show that economic complexity (which measures technological and productive capabilities) determines cross-country differences regarding the effects of RER misalignments on countries’ long-term growth rates. The results suggest that exchange rate devaluations may not be effective for countries at the top end of the technological ladder while an overvalued RER may damage the long-term growth rate of countries with low levels of economic complexity. Originality/value This paper contributes to the literature by empirically investigating the impact of RER misalignments in countries with distinct technological and productive capabilities based on the recent developments of countries’ economic complexity analysis. It investigates whether more diversified and complex economies are less sensitive to RER misalignments as they can adapt their production, undertake other tasks, create new products and increase the quality of products they produce. Less complex economies, on the other hand, are less capable of innovating because it demands productive capabilities they do not have, and hence, they are more dependent on their current export basket.

The Significant Impact of the COVID-19 Pandemic on Supply Chains

2022 ◽  
pp. 185-202
Author(s):  
Ana Paula Lopes
Keyword(s):  
Supply Chains ◽  
Consumer Demand ◽  
Lessons Learned ◽  
The Other ◽  
Operational Decisions ◽  
Demand And Supply ◽  
The World ◽  
Containment Measures ◽  
The Impact

As the COVID-19 pandemic has spread across the world, the existence of disruptions in demand and supply have become more severe, conducted by containment measures taken by countries and affecting different sectors around the world. Although businesses and workplaces are restarting activities in some countries, with containment measures gradually being lifted, overall consumer demand is expected to remain low, also determined by the loss of jobs and income. Therefore, the scale of the impact on supply chains exceeded anything most companies had anticipated. This study aims to understand how companies were affected and identify some lessons learned about their vulnerabilities and the possible ways to address them in the long term. On the other hand, it is intended to reveal some of the impacts of COVID-19 and make some practical suggestions that can help in political and operational decisions to strengthen and build additional resilience in supply chains in the future.

scholarly journals Impact of long-term supplementation of zinc and selenium on their content in blood and hair in goats

2011 ◽  
Vol 56 (No. 2) ◽  
pp. 63-74 ◽  
Author(s):  
L. Pavlata ◽  
M. Chomat ◽  
A. Pechova ◽  
L. Misurova ◽  
R. Dvorak
Keyword(s):  
Blood Plasma ◽  
Whole Blood ◽  
Average Concentration ◽  
The Other ◽  
Control Group ◽  
Selenium Yeast ◽  
Hair Samples ◽  
The Impact ◽  
Se Status

This paper evaluates the impact of long-term supplementation of different forms of zinc (Zn) and selenium (Se) on the content of these substances in the blood and hair of goats. Two analogous supplementation experiments were performed. 37 goats divided into four groups were used in the first trial with the Zn supplementation. Group A (n = 10) was a control group (with no Zn administered). A further three groups (B, C, D) were supplemented with Zn in various forms. Group B (n = 9) with zinc oxide, Group C (n = 9) with zinc lactate and Group D (n = 9) with zinc chelate. The second trial with Se supplementation was carried out on 20 goats divided into four groups. Group E (n = 5) was a control group. The other three groups were administered Se. Group F (n = 5) was supplied with a selenium lactate-protein complex, Group G (n = 5) with sodium selenite and Group H (n = 5) with selenium yeast. Three months later blood and hair samples were taken from all animals and Zn and Se concentrations were determined in whole blood, plasma, and hair. Glutathione peroxidase (GSH-Px) activity was determined in the Se supplementation trial group. At the end of the trial the Zn concentrations in plasma and whole blood were without major differences between the groups. The plasma concentration of Zn did not increase from the initial value at the start of the trial. In hair the average concentration of Zn was 95.2&ndash;100.0 mg/kg<br />in all groups. No conclusive relation was confirmed between the values of Zn in hair and its concentration in blood. The Se concentration in whole blood (&micro;g/l) at the end of trial in supplemented groups (F &ndash; 188.8 &plusmn; 24.6; G &ndash; 197.2 &plusmn; 10.9; H &ndash; 190.1 &plusmn; 26.3) was significantly higher (P &lt; 0.01) than in the control group (E &ndash; 103.1 &plusmn; 23.5). Similarly, the activity of GSH-Px (&micro;kat/l) was significantly higher in all supplemented groups (F &ndash; 872.3 &plusmn; 94.8; G &ndash; 659.5 &plusmn; 176.4; H &ndash; 839.8 &plusmn; 150.8) than in the control group (E &ndash; 379.1 &plusmn; 63.5). Se content in hair (&micro;g/kg) was higher also in all trial groups (F &ndash; 242.3 &plusmn; 41.5; G &ndash; 200.5 &plusmn; 46.9; H &ndash; 270.0 &plusmn; 106.8) than in the control group (E &ndash; 174.7 &plusmn; 38.0). However, it was significantly (P &lt; 0.05) higher only in Group F. A conclusive correlation was identified between the Se concentration in whole blood and its content in hair (r = 0.54; P &lt; 0.05; n = 20). Based on the results it can be concluded that none of the supplemented forms of Zn increased its concentration in blood, plasma and hair. On the other hand, the administration of Se led to an increase in the Se concentration in blood, increased the activity of GSH-Px in whole blood and the Se content in hair. Based on the proven correlation and regression relation between the Se concentration in blood and its content in hair, hair can be considered as a suitable material for the diagnosis of long-term Se status in goats. Goats with sufficient Se status are those that have more than 160 &micro;g/kg of Se in hair dry weight.

Ending Civil Wars: A Case for Rebel Victory?

2010 ◽  
Vol 34 (4) ◽  
pp. 7-36 ◽  
Author(s):  
Monica Duffy Toft
Keyword(s):  
Civil War ◽  
Statistical Analysis ◽  
Policy Analysis ◽  
Civil Wars ◽  
The Other ◽  
War Termination ◽  
Negotiated Settlement ◽  
Long Term Stability ◽  
Negotiated Settlements

Since 1990, negotiated settlements have become the preferred means for settling civil wars. Historically, however, these types of settlements have proven largely ineffective: civil wars ended by negotiated settlement are more likely to recur than those ending in victory by one side or the other. A theoretical and statistical analysis of how civil wars end reveals that the type of ending influences the prospects for longer-term outcomes. An examination of all civil war endings since 1940 finds that rebel victories are more likely to secure the peace than are negotiated settlements. A statistical analysis of civil wars from 1940 to 2002 and the case of Uganda illustrate why rebel victories result in more stable outcomes. Expanding scholarly and policy analysis of civil war termination types beyond the current default of negotiated settlement to include victories provides a much larger set of cases and variables to draw upon to enhance understanding of the conditions most likely to support long-term stability, democracy, and prosperity.

scholarly journals THE IMPACT OF THE ACQUISITION OF THE LETTERS IN A SYSTEMATIC LITERACY ON WRITING SKILLS

2014 ◽  
Vol 61 (1) ◽  
pp. 98-104
Author(s):  
Marija Ropič
Keyword(s):  
Key Words ◽  
Prior Knowledge ◽  
Writing Skills ◽  
The Other ◽  
Simultaneous Treatment ◽  
And Gender ◽  
The Impact ◽  
Initial Literacy

Learning letters is associated with a long-term learning. Two basic models are present in obtaining letters in a systematic literacy in Slovenia and abroad. One represents a separate acquisition of the uppercase and lowercase printed letters (sequentially) and the other deals with letters simultaneously. In practice, teachers often asked themselves, especially in times of reforms in literacy, which model of the acquisition of the letters in initial literacy is more efficient. The research focused on the effect of the two most frequently chosen procedures for acquiring letters of structured literacy in Slovenia, namely the simultaneous treatment of the uppercase and lowercase printed letters (lowercase cursive letters and upper-case cursive letters) and consecutive treatment of letters (uppercase printed letters, lowercase printed letters, lowercase cursive letters, and at last, uppercase printed letters). Furthermore, the focus of the research was on the impact of gender on the ability to write. The incidence of errors was observed in terms of selected procedures for acquiring the letters in groups and gender. At the same time, the effect of consolidation of writing individual letters (uppercase and lowercase printed letters in 2nd class, and lowercase and uppercase cursive letters in 3rd class), was examined. Key words: literacy, the process of acquiring letters, 2nd class, 3rd class, prior knowledge, writing skills.

Influence of bending radius on longitudinal stresses in long operation pipelines

2020 ◽  
Vol 10 (3) ◽  
pp. 234-242
Author(s):  
Robert М. Askarov ◽  
◽  
Aydar К. Gumerov ◽  
Rinat M. Karimov ◽  
Khiramagomed Sh. Shamilov ◽  
...  
Keyword(s):  
Technical Condition ◽  
Regulatory Requirements ◽  
Bend Radius ◽  
Term Operation ◽  
Mandatory Requirement ◽  
Bending Radius ◽  
New Construction ◽  
The Impact ◽  
Long Operation

Calculations of stress-strain state of pipelines are performed in accordance with the unified regulatory requirements, which do not take into account facilities operation. Thus, the limitation of minimal allowable bend radius with the value of 1000 pipe diameters (1000D) can be considered justified in relation to a new construction project, but the problem is that it is applied to all pipelines independently of its service life. At the same time the modern smart pigging technologies allow for obtaining precise data on bend radius of operated pipelines, and the diagnostics results indicate, that mandatory requirement for minimal value of 1000D frequently contradicts the actual technical condition of researched objects. The authors performed the analysis of standard formula for calculation of longitudinal stresses, considered the impact on the calculated value of its separate constituents: values of pressure, temperature difference and bend radius. The conclusion is made about the necessity for reassessment of the current regulations for scientific justification of acceptable values of pipeline longitudinal stresses. It is established, that the primary factor, which is responsible for forming the value of longitudinal stresses of the pipelines during long-term operation is the bend radius.

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