scholarly journals Investigation of salt migration in the ground saturated with a chloride-sulphate sodium-magnesium solution in freezing-thawing cycles**

2019 ◽  
Vol 265 ◽  
pp. 06008
Author(s):  
Boris V. Grigoriev ◽  
Yulia F. Yanbikova
Keyword(s):  
Negative Impact ◽  
Experimental Unit ◽  
Freezing Front ◽  
Load Bearing Capacity ◽  
Salt Migration ◽  
Salt Ions ◽  
Sodium Magnesium ◽  
Moist Ground ◽  
Measuring Unit ◽  
Front Movement

Among the variety of objects in the permafrost zone, soils are encountered, including cryopegs – highly mineralized solutions that have excessive pore pressure. Generally, they have a negative impact, reducing the load-bearing capacity of the ground and causing corrosion of concrete and metal constructions. The study of cryopegs does not receive enough attention from Russian and foreign researchers, not least because of the peculiarities of the thermodynamic state they exist in, therefore detailed investigation of this cryologic object is required in the field and in laboratory conditions. In the presented research the authors study the mechanism of the migration of salt ions in pore water in an enclosed volume of ground during the freezing front movement. To do this, the authors developed an experimental unit and created a measuring unit where the studied moist ground is inserted. Temperature can be set on the opposite sides of the measuring unit. Controlling the extent and speed of temperature change provides a means to regulate freezing front movement (directed from top to bottom). After a number of freezing-thawing cycles salt compositions and concentrations are checked and measured in four intervals of sampling. As a result of the experiments a significant increase in concentration was found at opposite sampling points, and in particular at the beginning of the freezing front movement.

scholarly journals Freezing Fronts and their Possible Influence upon Processes of Subglacial Erosion and Deposition

1981 ◽  
Vol 2 ◽  
pp. 52-56 ◽  
Author(s):  
John Menzies
Keyword(s):  
Shear Strength ◽  
Pore Water ◽  
Thermal Regime ◽  
Water Movement ◽  
Water Interface ◽  
Freezing Front ◽  
Erosion And Deposition ◽  
Depositional Processes ◽  
Ice Water ◽  
Front Movement

Recent studies have shown the important influence of pore-water movement and the subglacial thermal regime on processes of erosion and deposition at the subglacial interface. the influence of migrating freezing fronts within subglacial material has been largely ignored. the phenomena of ice-water interface processes will be examined and their relevance to subglacial processes illustrated. four case studies are presented that deal with the various effects that freezing-front movement may have on pore water, consolidation, shear strength, and likely diagenetic characteristics of subglacial deposits. the influence upon erosional and depositional processes will be outlined, and a mechanism related to potential surge-like conditions within the subglacial zone postulated.

scholarly journals Impact of the fire on the bearing capacity of the ordinary concrete used in reinforced concrete structures in Burundi. History and architecture

Vestnik MGSU ◽  
2021 ◽  
pp. 1567-1572
Author(s):  
Emmanuel Mikerego ◽  
Donatien Nduwimana
Keyword(s):  
Reinforced Concrete ◽  
Bearing Capacity ◽  
Negative Impact ◽  
Heating Temperature ◽  
Concrete Structures ◽  
Reinforced Concrete Structures ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Ordinary Concrete ◽  
The Impact

Introduction. This paper presents the results of an assessment of the impact of fire on the bearing capacity of the ordinary concrete, to be taken into account in the rehabilitation of fire-damaged reinforced concrete structures in Burundi. Materials and methods. Experimental samples of the ordinary concrete made respectively of coarse river aggregates and crushed coarse quarry aggregates were prepared and subjected to different heating temperatures (250, 350, 450, 600 and 900 °C) simulating the fire. After natural cooling, experimental samples were subjected to compression test; and diagrams showing the loss of the load-bearing capacity of the ordinary concrete used in reinforced concrete structures in Burundi were drawn. Results. Negative impact of the fire on the load-bearing capacity of the ordinary concrete occurs above of 350 °C of heating temperature. Concrete made of crushed coarse quarry aggregates loses 50 and 78 % of its bearing capacity at around 525 and 900 °C of heating temperature, respectively. Similarly, concrete made of coarse river aggregates loses 50 and 70 % of its load-bearing capacity respectively at 600 and 900 °C of heating temperature. An evaluation curve of the after-fire bea­ring capacity of the concrete used in reinforced concrete structures in Burundi is established. Conclusions. The negative impact of the fire on the load-bearing capacity of the ordinary concrete occurs above of 350 °C of heating temperature. Concretes made of crushed coarse quarry aggregates and concrete made of coarse river aggregates lose 50 % of its bearing capacity at around 525 and 600 °C of heating temperature respectively. Knowing the heating temperature that the fire-damaged reinforced concrete structure has undergone is indispensable in deciding on its demolition or rehabilitation.

scholarly journals Lubrication of Rough Short Bearing on Shliomis Model by Ferrofluid Considering Viscosity Variation Effect

2019 ◽  
Vol 4 (4) ◽  
pp. 982-997
Author(s):  
Mohmmadraiyan M. Munshi ◽  
A. R. Patel ◽  
G. M. Deheri
Keyword(s):  
Bearing Capacity ◽  
Reynolds Equation ◽  
Negative Impact ◽  
Random Variable ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Realistic Situation ◽  
Transverse Roughness ◽  
The Impact ◽  
Positive Effect

This study aims to explore the impact caused by change in viscosity and the roughness of a bearing surface on a ferrofluid lubrication of Shliomis model for short bearing. Based on this model and the Tipei (1962) model, a new resultant Reynolds equation has been found that shows thermal variation. The Christensen and Tonder models have been taken to derive the transverse roughness stochastically. An assumed mean has been taken for the probability density function with a non-zero value. This value is assigned to a random variable that measures the bearing’s surface roughness. This creates a more realistic situation that can have a lot of field applications. The model defines the problem mathematically while defining boundary conditions. It also uses the Simpson’s method to derive a conclusion. The results thus obtained are discussed in terms of pressure distribution and load bearing capacity. The graphical results obtained suggest that in the presence of magnetization, there is a significant enhance in the load bearing capacity. This positive effect can easily nullify the negative impact of the thermal effect. The short bearing approximation shown here is an example of the probable applications. Ferrofluids in the presence of magnetic fields significantly enhance the performance of a short bearing.

scholarly journals Contamination of Soil with Diesel Oil, Application of Sewage Sludge and Content of Macroelements in Oats

2020 ◽  
Vol 231 (11) ◽  
Author(s):  
Mirosław Wyszkowski ◽  
Jadwiga Wyszkowska ◽  
Agata Borowik ◽  
Natalia Kordala
Keyword(s):  
Sewage Sludge ◽  
Soil Contamination ◽  
Petroleum Product ◽  
Avena Sativa ◽  
Negative Impact ◽  
Diesel Oil ◽  
Average Content ◽  
Above Ground Biomass ◽  
Sodium Magnesium ◽  
Nitrogen Phosphorus

AbstractThe aim of the study was to determine the effect of soil contamination with diesel oil (0, 5, 10 and 15 mL/kg d.m. of soil) on the macroelement content (nitrogen, phosphorus, potassium, sodium, magnesium and calcium) in the above-ground parts of oats (Avena sativa L.). A remediation effect of sludge as a substance which reduces the negative impact of this petroleum product on its element content in oats was also evaluated. Sewage sludge was applied in doses 0, 4, 8 and 12 g/kg of soil. The macroelement content in the above-ground parts of oats depended on the soil contamination with diesel oil and on the addition of sewage sludge to the soil. Soil contamination with diesel oil caused significant changes in the content of all macroelements in the above-ground biomass of oats. Increasing doses of the petroleum product in the series without sewage sludge decreased the content of all macroelements, except phosphorus and calcium. The highest effect was observed for the content of sodium in oats. The addition of sewage sludge to the soil alleviated the negative impact of diesel oil on the chemical composition of the plants. The application of sewage sludge to soil resulted in an increase in average content of nitrogen, sodium and magnesium (as opposed to phosphorus and partly calcium) in the above-ground parts of oats, compared to the series without sewage sludge.

scholarly journals EFFECT OF POLYETHYLENE GLYCOL (PEG) 6000 ON GREEN MUSTARD (Brassica juncea L.) GERMINATION AND GROWTH

2020 ◽  
Vol 7 (2) ◽  
pp. 1-8
Author(s):  
Garri Abdi Nusantara ◽  
Tundjung T. Handayani ◽  
Zulkifli Zulkifli ◽  
Sri Wahyuningsih
Keyword(s):  
Polyethylene Glycol ◽  
Drought Stress ◽  
Chlorophyll Content ◽  
Brassica Juncea ◽  
Negative Impact ◽  
Experimental Unit ◽  
Vegetable Production ◽  
Peg 6000 ◽  
Levene Test ◽  
Polyethylene Glycol 6000

The frequent drought in Indonesia has caused many farmers to experience a decline in vegetable production, one of which is green mustard. The green mustard is not resistant to drought, so water supply is an aspect that must be given special attention in cultivating green mustard. The objective of this study was to know whether the seedling and growth of seedling of green mustard (Brassica juncea L.) can grow well under drought stress by Polyethylene glycol 6000. This study was conducted in the Laboratory of Plant Physiology, Department of Biology, Faculty of Mathematics and Natural Science, the University of Lampung in 2019. This study was conducted in a Completely Randomized Design with the main factor is Polyethylene glycol 6000 with three levels: 0% w/v, 10% w/v, 20% w/v, and 30% w/v. Each combination of treatments was repeated five times. The number of the experimental unit was 20. The observed variables in this study were the percentage of seed germination, length of leaf, the width of leaf, a,b chlorophyll content, and total chlorophyll content. The data was homogenize using the Levene test, then continued to analyze using ANOVA at a 5% significant level and proceed with HSD test significant level 5% to determine the differences between the treatment. The result showed that under drought stress by Polyethylene glycol 6000 started to affect green mustard seedling and growth of seedling at the level of PEG 6000 concentration 20% w/v while the number of leaves not affected. The conclusion was PEG 6000 gave a negative impact on the green mustard and the green mustard induced by PEG 6000 10% w/v more adaptive than PEG 6000 20 w/v.

scholarly journals Results of testing a lenticular coating block support unit

2020 ◽  
Vol 10 (3) ◽  
pp. 398-405
Author(s):  
Sergey V. Grigoriev ◽  
◽  
Vladimir I. Palagushkin ◽  
Inna Y. Petukhova ◽  
Dmitry O. Astrakhantcev ◽  
...  
Keyword(s):  
Experimental Study ◽  
Spot Welding ◽  
Test Bench ◽  
Contact Spot ◽  
Design Solution ◽  
Experimental Unit ◽  
Vertical Position ◽  
Load Bearing Capacity ◽  
Support Unit ◽  
Soldered Joint

The paper aims to study options for connecting belt elements from a profiled sheet, to develop a technology for manufacturing support units and to determine their load-bearing capacity by testing nodal elements with connecting sheets using electric rivets and soldering pre-rolled profiled sheets. An experimental study of nodal elements was performed in a vertical position on a test bench. Fragments of the support assembly with a seam-soldered connection and with the connection of belt elements using contact spot welding were tested. It is shown that seam-soldered joints provide the necessary strength thus being suitable as a basis for the flawless manufacture of an experimental unit. For welding connection, two options of the support unit were considered, i.e. with plastic support ribs and without ribs. The junction of profiled sheets using electric rivets is more technologically advanced than a seam-soldered joint. The conducted tests elaborated the proposed design solution and the method of manufacturing the connection of profiled sheets (support units). Tests of operability, reliability and strength of this junction with various connections were carried out.

scholarly journals Pengaruh proses steam pada daun kelor (Moringa oleifera) dan asam fulvat terhadap performa ayam broiler

2018 ◽  
Vol 16 (2) ◽  
pp. 1
Author(s):  
H A Sukria ◽  
IES Nugraha ◽  
D M Suci
Keyword(s):  
Body Weight ◽  
Fulvic Acid ◽  
Analysis Of Variance ◽  
Moringa Oleifera ◽  
Negative Impact ◽  
Steam Treatment ◽  
Experimental Unit ◽  
Final Body Weight ◽  
Broiler Performance ◽  
Leaf Meal

<p>ABSTRAK</p><p>Penelitian ini bertujuan untuk mengetahui pengaruh proses steam pada daun kelor (Moringa oleifera) terhadap performa ayam broiler. Sebanyak 120 DOC di bagi ke dalam 5 perlakuan ransum dengan 3 ulangan yang dipelihara selama 35 hari. Pakan yang diberikan terdiri dari dua periode yaitu starter (protein kasar 22,07% dan energi metabolis 305,65 kkal kg-1) dan finisher (protein kasar 20,3% dan energi metabolis 3120 kkal kg-1). Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) yang terdiri dari lima perlakuan ransum yaitu: P0 (Control), P1 (Control + 5% daun kelor tanpa steam), P2 (Control+5% daun kelor tanpa steam + 0,5% asam fulvat), P3 (Control+5% daun kelor steam), dan P4 (Control+5% tepung daun kelor steam dan 0,5% asam fulvat). Data yang diperoleh dianalisis dengan Analysis of Variance (ANOVA) dan uji Duncan Multiple Range Test. Hasil penelitian menunjukkan penambahan daun kelor dan asam fulvat pada ransum mempengaruhi bobot badan ayam broiler (P&lt;0,01). Penambahan daun kelor steam menghasilkan bobot badan akhir ayam broiler yang sama jika dibandingkan dengan perlakuan kontrol. Penambahan daun kelor steam dengan asam fulvat (P4) menghasilkan bobot badan akhir yang lebih rendah dibandingkan perlakuan dengan asam fulvat tanpa steam (P2 dan P3)(P&lt;0,01). Berdasarkan hasil tersebut menunjukan bahwa asam fulvat yang dipanaskan memberikan pengaruh yang negatif terhadap performa ayam broiler.</p><p><br />Kata kunci: asam fulvat, daun kelor, kakas, performa, proses steam</p><p><br />ABSTRACT<br />The research was conducted to investigate the effect of hydro thermal process (steam) of Moringa leaf meal and fulvic acid on performance of broiler chicken. The120 heads of Day Old Chicken (DOC) were used in this experiment. A completely randomized design was used in this experiment with 5 treatments and 3 replications with 8 broilers in each experimental unit and was reared for 35 days. The treatments were P0 (Control), P1 (Control+5% steamed Moringa leaf), P2 (Control+5% unsteamed Moringa leaf meal and 0.5% fulvic acid), P3 (Control+5% steamed Moringa leaf meal), and P4 (Control+5% steamed Moringa leaf meal and 0.5% fulvic acid). All data were analysed by analysis of variance and Duncan multiple ranges. The result of this research showed that Moringa leaf meal and fulvic acid significantly affected (P&lt;0.01) broiler performance. The addition of Moringa leaf meal with steamed process did not significantly affect on final body weight compared to the control. Meanwhile the addition of Moringa leaf powder and fulvic acid with steamed process resulted in significantly the lower final body weight of the broiler compared to the treatments of fulvic acid without steam process. From this result can be concluded that that steam treatment of fulvic acid result in negative impact on the broiler performance.</p><p><br />Key words: carcass, fulvic acid, Broiler performance, Moringa leaves, steam process</p>

Mitochondrial hyperfusion: a friend or a foe

2020 ◽  
Vol 48 (2) ◽  
pp. 631-644 ◽  
Author(s):  
Rajdeep Das ◽  
Oishee Chakrabarti
Keyword(s):  
Negative Impact ◽  
Cellular Stress ◽  
Cellular Homeostasis ◽  
Mitochondrial Population

The cellular mitochondrial population undergoes repeated cycles of fission and fusion to maintain its integrity, as well as overall cellular homeostasis. While equilibrium usually exists between the fission–fusion dynamics, their rates are influenced by organellar and cellular metabolic and pathogenic conditions. Under conditions of cellular stress, there is a disruption of this fission and fusion balance and mitochondria undergo either increased fusion, forming a hyperfused meshwork or excessive fission to counteract stress and remove damaged mitochondria via mitophagy. While some previous reports suggest that hyperfusion is initiated to ameliorate cellular stress, recent studies show its negative impact on cellular health in disease conditions. The exact mechanism of mitochondrial hyperfusion and its role in maintaining cellular health and homeostasis, however, remain unclear. In this review, we aim to highlight the different aspects of mitochondrial hyperfusion in either promoting or mitigating stress and also its role in immunity and diseases.

Health Communication: Implications for Diverse Populations

2011 ◽  
Vol 18 (1) ◽  
pp. 12-19
Author(s):  
Amy Hasselkus
Keyword(s):  
Health Care ◽  
Health Communication ◽  
Negative Impact ◽  
Linguistically Diverse ◽  
Good Health ◽  
The United States ◽  
Poor Health ◽  
Health Care Decisions ◽  
Diverse Backgrounds ◽  
Health Related

The need for improved communication about health-related topics is evident in statistics about the health literacy of adults living in the United States. The negative impact of poor health communication is huge, resulting in poor health outcomes, health disparities, and high health care costs. The importance of good health communication is relevant to all patient populations, including those from culturally and linguistically diverse backgrounds. Efforts are underway at all levels, from individual professionals to the federal government, to improve the information patients receive so that they can make appropriate health care decisions. This article describes these efforts and discusses how speech-language pathologists and audiologists may be impacted.

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