In situ creep properties in ice-rich permafrost soil

1986 ◽  
Vol 23 (4) ◽  
pp. 504-514 ◽  
Author(s):  
K. W. Savigny ◽  
N. R. Morgenstern
Keyword(s):  
Canadian Arctic ◽  
Permafrost Soil ◽  
Creep Properties ◽  
Factors Affecting ◽  
Naturally Occurring ◽  
Permafrost Soils ◽  
Bear River ◽  
Creep Deformations ◽  
Significant Factors

An in situ analysis of naturally occurring creep has been carried out at the proposed Canadian Arctic Gas pipeline crossing of Great Bear River in the Northwest Territories. This is the third of four papers that describe the study. The borehole inclinometer system and monitoring procedures used to determine in situ movement are described. Significant factors affecting the accuracy of the system are assessed. External factors causing movement of the inclinometer casing are also assessed and movements caused by these factors are separated from natural ground movements. The magnitude and nature of naturally occurring creep deformations are discussed. Key words: Mackenzie Valley, pipelines, slopes, permafrost, soils, geotechnical, inclinometers, creep.

Creep behaviour of undisturbed clay permafrost

1986 ◽  
Vol 23 (4) ◽  
pp. 515-527 ◽  
Author(s):  
K. W. Savigny ◽  
N. R. Morgenstern
Keyword(s):  
Creep Behaviour ◽  
Canadian Arctic ◽  
Time Behaviour ◽  
Frozen Soils ◽  
Creep Properties ◽  
Naturally Occurring ◽  
Bear River ◽  
River Site ◽  
Pipeline Crossing

An in situ analysis of naturally occurring creep has been carried out at the proposed Canadian Arctic Gas pipeline crossing of Great Bear River in the Northwest Territories. This is the last of four papers that describe the study. Creep properties of natural and reconstituted frozen soils are briefly reviewed. A laboratory programme to measure creep properties of undisturbed ice-rich glaciolacustrine clay samples from the Great Bear River site is described in detail. The results are analysed to determine empirical parameters for constitutive equations that describe the stress–strain–time behaviour of the material. Key words: Mackenzie Valley, pipelines, slopes, ice-rich, soils, permafrost, geotechnical, creep, laboratory.

Geotechnical condition of slopes at a proposed pipeline crossing, Great Bear River valley, Northwest Territories

1986 ◽  
Vol 23 (4) ◽  
pp. 490-503 ◽  
Author(s):  
K. W. Savigny ◽  
N. R. Morgenstern
Keyword(s):  
Northwest Territories ◽  
Canadian Arctic ◽  
Field Investigation ◽  
Naturally Occurring ◽  
Clay Deposits ◽  
Permafrost Soils ◽  
Bear River ◽  
Valley Area ◽  
Pipeline Crossing

An in situ analysis of naturally occurring creep has been carried out in ice-rich permafrost soils underlying a slope at the proposed Canadian Arctic Gas pipeline crossing of Great Bear River in the Northwest Territories. This is the second of four papers that describe the study. Field investigation and instrument installation techniques are described and geological, geotechnical, and geothermal results are presented. The data presented here are intended to facilitate clear interpretation of deformation observations in the third paper. The data are representative of ice-rich glaciolacustrine clay deposits that are widespread in the mid-Mackenzie Valley area. Key words: Mackenzie Valley, pipelines, slopes, permafrost, soils, drilling, sampling, geotechnical, geothermal.

scholarly journals Two Novel Approaches Used to Produce Biodiesel from Low-Cost Feedstocks

2010 ◽  
Vol 3 (1) ◽  
pp. 23-27 ◽  
Author(s):  
Xiaohu Fan ◽  
Xi Wang ◽  
Feng Chen
Keyword(s):  
High Performance ◽  
Low Cost ◽  
Waste Cooking Oil ◽  
Biodiesel Production ◽  
Economic Viability ◽  
Factors Affecting ◽  
Cooking Oil ◽  
Preliminary Study ◽  
Significant Factors

The price of feedstock is one of the most significant factors affecting the economic viability of biodiesel manufacturer. Many approaches were investigated to reduce the biodiesel production cost. The present work gave a preliminary study of two approaches to economically produce biodiesel from waste cooking oil (WCO) and flaked cottonseed. One was the use of ultrasound-assisted synthesis of biodiesel from WCO. The other was the application of in situ transesterification from flaked cottonseed. Gas chromatography (GC) and High performance liquid chromatography (HPLC) results demonstrated the feasibility of using both approaches to produce biodiesel from low-cost feedstock.

The measurement of the rocking behaviour of graphite bricks using ultrasound

2004 ◽  
Vol 218 (10) ◽  
pp. 1213-1222
Author(s):  
C Holmes ◽  
B W Drinkwater
Keyword(s):  
Nuclear Reactors ◽  
Bulk Material ◽  
Nuclear Fission ◽  
Scanning System ◽  
Contact Pressure Distribution ◽  
Fission Reaction ◽  
Factors Affecting ◽  
Interfacial Behaviour ◽  
Significant Factors

Assemblies of graphite bricks are found in graphite cored nuclear reactors throughout the world. In such reactors the graphite bricks, which are used to moderate the nuclear fission reaction, are assembled in arrays of the order of 10 m in height and 10m in width. The bricks themselves come in a range of shapes and sizes. The static and dynamic response of such structures is dependent on both the properties of the bulk material and the nature of the interface between individual bricks. Typical real surfaces exhibit some form of macroscopic waviness in addition to the microscopic roughness and therefore only a small fraction of the surfaces are in contact. This interfacial behaviour has been found to be one of the most significant factors affecting the rocking behaviour of dry-jointed structures, such as graphite cored reactors, and has proved one of the most difficult to explore experimentally. This paper describes a novel application of the ultrasonic measurement technique for the investigation of the effect of microscopic and macroscopic surface features on the rocking behaviour of graphite bricks. An ultrasonic scanning system has been combined with a loading rig to enable factors such as the size of the contact area and its position relative to the edge of a brick to be measured in situ as the brick is loaded. The ultrasound is used to measure the contact pressure distribution between a brick and a rigid foundation. This information has been used in a model to predict the rocking stiffness of the brick-foundation system and good comparisons with rocking experiments achieved. This measurement system could also be used to study the rocking behaviour of other systems of dry contacting blocks such as those found in costal defences and ancient buildings.

Simulation of non-stationary thermal fields from a buried thermally insulated pipeline and its diagnostics

2007 ◽  
Vol 5 ◽  
pp. 127-132
Author(s):  
N.A. Vaganova
Keyword(s):  
Thermal Imaging ◽  
Software Package ◽  
Clay Soil ◽  
Underground Pipeline ◽  
Main Pipeline ◽  
Factors Affecting ◽  
Thermal Fields ◽  
Thermal Imaging Equipment ◽  
Principal Possibility ◽  
Significant Factors

To detect damage to the underground pipeline, a mathematical model, allowing to take into account the most significant Factors affecting the distribution of temperature on the day surface. To implement this model, a software package has been developed and results of numerical calculations. With the help of these calculations, in particular, It is established that modern thermal imaging equipment has a principal possibility to determine an unauthorized frame in the main pipeline at a depth of two meters in clay soil.

How Artefacts Do Leadership: A Ventriloquial Analysis

2021 ◽  
pp. 089331892199807
Author(s):  
Jonathan Clifton ◽  
Fernando Fachin ◽  
François Cooren
Keyword(s):  
Organizational Communication ◽  
Recent Work ◽  
Distributed Leadership ◽  
Network Theory ◽  
Actor Network Theory ◽  
Fine Grained ◽  
Naturally Occurring ◽  
Human Actors

To date there has been little work that uses fine-grained interactional analyses of the in situ doing of leadership to make visible the role of non-human as well as human actants in this process. Using transcripts of naturally-occurring interaction as data, this study seeks to show how leadership is co-achieved by artefacts as an in-situ accomplishment. To do this we situate this study within recent work on distributed leadership and argue that it is not only distributed across human actors, but also across networks that include both human and non-human actors. Taking a discursive approach to leadership, we draw on Actor Network Theory and adopt a ventriloquial approach to sociomateriality as inspired by the Montreal School of organizational communication. Findings indicate that artefacts “do” leadership when a hybrid presence is made relevant to the interaction and when this presence provides authoritative grounds for influencing others to achieve the group’s goals.

scholarly journals The Level of Conus Medullaris in 629 Healthy Japanese Individuals

2021 ◽  
Vol 10 (14) ◽  
pp. 3182
Author(s):  
Hiroaki Nakashima ◽  
Keigo Ito ◽  
Yoshito Katayama ◽  
Mikito Tsushima ◽  
Kei Ando ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Magnetic Resonance ◽  
Pelvic Tilt ◽  
Pelvic Incidence ◽  
Multivariate Regression Analysis ◽  
Conus Medullaris ◽  
Magnetic Resonance Images ◽  
Factors Affecting ◽  
Adult Volunteers ◽  
Significant Factors

The conus medullaris typically terminates at the L1 level; however, variations in its level and the factors associated with the conus medullaris level are unclear. We investigated the level of conus medullaris on magnetic resonance imaging in healthy volunteers. In total, 629 healthy adult volunteers (≥50 individuals of each sex and in each decade of age from 20 to 70) were enrolled. The level of the conus medullaris was assessed based on the T2-weighted sagittal magnetic resonance images, and factors affecting its level were investigated employing multivariate regression analysis including the participants’ background and radiographical parameters. L1 was the most common conus medullaris level. Participant height was significantly shorter in the caudally placed conus medullaris (p = 0.013). With respect to the radiographical parameters, pelvic incidence (p = 0.003), and pelvic tilt (p = 0.03) were significantly smaller in participants with a caudally placed conus medullaris. Multiple regression analysis showed that the pelvic incidence (p < 0.0001) and height (p < 0.0001) were significant factors affecting the conus medullaris level. These results indicated that the length of the spinal cord varies little among individuals and that skeletal differences affect the level of the conus medullaris.

Fabrication of monodisperse polypyrrole/SBA-15 composite for the selective removal of Cr(Ⅵ) from aqueous solutions

2021 ◽  
Author(s):  
Liang Wang ◽  
Peng Gao ◽  
Mengxin Liu ◽  
Ziqing Huang ◽  
Shixia Lan ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Adsorption Process ◽  
In Situ Polymerization ◽  
Selective Removal ◽  
Factors Affecting

Monodisperse polypyrrole/SBA-15 composite (PPy/SBA-15) was fabricated by in-situ polymerization and used for Cr(Ⅵ) adsorption from aqueous solution. PPy/SBA-15 was characterized by numerous approaches. Factors affecting the Cr(Ⅵ) adsorption process included...

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