4,429 research outputs found
Case Study of Heat Transfer during Artificial Ground Freezing with Groundwater Flow
No full textFor the artificial ground freezing (AGF) projects in highly permeable formations, the effect of groundwater flow cannot be neglected. Based on the heat transfer and seepage theory in porous media with the finite element method, a fully coupled numerical model was established to simulate the changes of temperature field and groundwater flow field. Firstly, based on the classic analytical solution for the frozen temperature field, the model’s ability to solve phase change problems has been validated. In order to analyze the influences of different parameters on the closure time of the freezing wall, we performed the sensitivity analysis for three parameters of this numerical model. The analysis showed that, besides the head difference, the thermal conductivity of soil grain and pipe spacing are also the key factors that control the closure time of the frozen wall. Finally, a strengthening project of a metro tunnel with AGF method in South China was chosen as a field example. With the finite element software COMSOL Multiphysics® (Stockholm, Sweden), a three-dimensional (3D) numerical model was set up to simulate the change of frozen temperature field and groundwater flow field in the project area as well as the freezing process within 50 days. The simulation results show that the freezing wall appears in an asymmetrical shape with horizontal groundwater flow normal to the axial of the tunnel. Along the groundwater flow direction, freezing wall forms slowly and on the upstream side the thickness of the frozen wall is thinner than that on the downstream side. The actual pipe spacing has an important influence on the temperature field and closure time of the frozen wall. The larger the actual pipe spacing is, the slower the closing process will be. Besides this, the calculation for the average temperature of freezing body (not yet in the form of a wall) shows that the average temperature change of the freezing body coincides with that of the main frozen pipes with the same trend
Supplemental_material - Effect of Low-Dose Hydrocortisone Therapy in Adult Patients With Septic Shock: A Meta-Analysis With Trial Sequential Analysis of Randomized Controlled Trials
No full textSupplemental_material for Effect of Low-Dose Hydrocortisone Therapy in Adult Patients With Septic Shock: A Meta-Analysis With Trial Sequential Analysis of Randomized Controlled Trials by Qing-Quan Lyu, Qi-Hong Chen, Rui-Qiang Zheng, Jiang-Quan Yu, and Xiao-Hua Gu in Journal of Intensive Care Medicine</p
Development and optimisation of a duplex real-time reverse transcription quantitative PCR assay targeting the VP7 and NS2 genes of African horse sickness virus
No full textNucleotide sequences of 52 South African isolates of African horse sickness virus (AHSV) collected during 2004–2005 and including viruses of all nine AHSV serotypes, were used to design and develop a duplex real-time reverse transcription quantitative PCR (RT-PCR) assay targeting the VP7 (S8) and NS2 (S9) genes of AHSV. The assay was optimized for detection of AHSV in fresh and frozen blood of naturally infected horses. Assay performance was enhanced using random hexamers rather than gene-specific primers for RT, and with denaturation of double-stranded RNA in the presence of random hexamers. The assay was efficient with a linear range of at least five orders of magnitude. The analytical sensitivity of the assay was 132 copies of the target genes (4125 copies per ml of blood), and the assay was at least 10-fold more sensitive than virus isolation on BHK-21 cells. The assay was also highly specific because it did not detect related orbiviruses, such as bluetongue and equine encephalosis viruses.ID: S0166093410000893; M3: Article; Accession Number: S0166093410000893; Author: M. Quan (a, b, ⁎); Author: C.W. Lourens (a, b); Author: N.J. MacLachlan (c); Author: I.A. Gardner (d); Author: A.J. Guthrie (a); Affiliation: Equine Research Centre, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa; Affiliation: Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa; Affiliation: Equine Viral Disease Laboratory, Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA; Affiliation: Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA; Keyword: African horse sickness virus; Keyword: Real-time quantitative RT-PCR; Keyword: VP7 gene; Keyword: NS2 gene; Keyword: Duplex; Number of Pages: 8; Language: English
Supplemental Material - Erythropoietin-producing hepatocyte kinase receptor A1 facilitating the prgression of SGC-7901 cells and its transplanted tumor by increasing the expression of interleukin-6 and vascular endothelial growth factor in tumor microenvironment
No full textSupplemental Material for Erythropoietin-producing hepatocyte kinase receptor A1 facilitating the prgression of SGC-7901 cells and its transplanted tumor by increasing the expression of interleukin-6 and vascular endothelial growth factor in tumor microenvironment by Yong-Cang Wang, Wen-Lin Zheng, Wei Yu, Rui-Liang Quan and Ya-Jun Zhao in European Journal of Inflammation</p
The Macaronesian liverwort Riccia boumanii Dirkse, Losada & M.Stech (Marchantiophyta: Ricciaceae) confirmed new to Asia by morphological and molecular evidence
No full textXiang, You-Liang, Ma, Xiao-Ying, Shen, Chao, Lu, Shi-Hui, Huang, Wen-Zhuan, Tian, Gui-Quan, Zhu, Rui-Liang (2022): The Macaronesian liverwort Riccia boumanii Dirkse, Losada & M.Stech (Marchantiophyta: Ricciaceae) confirmed new to Asia by morphological and molecular evidence. Cryptogamie, Bryologie 20 (14): 201-209, DOI: 10.5252/cryptogamie-bryologie2022v43a14, URL: http://dx.doi.org/10.5252/cryptogamie-bryologie2022v43a1
Co-curing bonding of carbon fibre/epoxy composite joints with excellent structure integrity using carbon fibre/PEEK tapes
No full textA novel co-curing process was proposed for the bonding of carbon fibre/epoxy composites by replacing traditional epoxy adhesives with carbon fibre/PEEK (CF/PEEK) tapes, with an attempt to improve the structure integrity. The lap-shear strengths, fatigue resistance and mode-I and mode-II fracture behaviour of the co-cured joints at 22 °C and 130 °C were investigated, and the failure mechanisms were also studied. The experimental results demonstrated that, by replacing an aerospace structural adhesive with surface-treated CF/PEEK tapes for the co-curing bonding of composite joints, the lap-shear strength of the joints had been increased by 47% and 68% at 22 °C and 130 °C, respectively; the fatigue life had been extended by 3.39 times; the mode-I fracture energy had been increased by 70% and 182% at 22 °C and 130 °C, respectively; and the mode-II fracture energy had been increased by 59% and 54% at 22 °C and 130 °C, respectively. An analysis on the failure surfaces of the tested specimens proved significant plastic deformation and breakage of the PEEK resin and extensive carbon fibre delamination being the main failure mechanisms of the CF/PEEK bonded joints. Overall, this study demonstrated a huge potential of replacing traditional film adhesives with CF/PEEK tapes for the co-curing bonding of aerospace composite joints with significantly enhanced structure integrity and thermal stability.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Structural Integrity & Composite
Affidavit of Florence Scrivner Toye re: transfer of Lease D, Carson Estate Company to Quan Bros., February 25, 1943
No full textDescribes transfer of Lease D with the Carson Estate Company from Florence Scrivner Toye to the Quan Bros. company; Quan Him Wong, George G. Quan. Signatures representing Florence Scrivner Toye, Harry G. Toye, Quan Him Wong, George G. Quan and Hamilton H. Cotton of the Carson Estate Company are included
[Affidavit] of Florence Scrivner Toye re: transfer of Lease D to Quan Bros., Carson Estate Company, January 6, 1943
No full textDescribes transfer of Lease D with the Carson Estate Company from Florence Scrivner Toye to the Quan Bros. company; Quan Him Wong, George G. Quan. No signatures on this document
A Numerical Study of Slug Tests in a Three‐Dimensional Heterogeneous Porous Aquifer Considering Well Inertial Effects
No full textHydraulic Travel Time Diagnosis Using Recovery Data from Short-Term Pumping Tests for Rapid Aquifer Characterization: A Numerical Study with Monte-Carlo Simulations
No full textIn the realm of groundwater science, characterization of heterogeneous aquifers is pivotal for resolving diverse groundwater resource and engineering-related problems that require the detailed spatial distribution of hydraulic parameters. As research progresses, one hydraulic tomographical method, which is based on hydraulic travel time inversion, emerges as a promising and rapid method due to its robust and efficient calculation. In the field, the acquisition of hydraulic excitation and head observation data required for inversion is less time-consuming. Data collection from a single hydraulic test (such as a pumping test) typically takes only a few minutes or even a few tens of seconds. However, the field application of this method faces challenges. Hydraulic travel time is typically generated in the early stages of hydrogeological tests (e.g., early drawdown of a pumping test), yet accurate data may not be readily available because of the noise signals from test equipment, which can contaminate travel time signals, leading to inaccurate inversion results. A potential solution lies in utilizing the smooth head observation during the recovery period after the pump is turned off, which yields more accurate travel times for inversion calculations. In this paper, the mathematical development suggests that the travel time of the recovery phase aligns with that of the pumping phase when pumping reaches a steady or quasi-steady state. Subsequently, by employing Monte-Carlo simulations, 1200 realizations of two-dimensional heterogeneous confined aquifer models were generated for simulating pumping tests with different pumping durations. The calculated head data were then utilized to compute the travel time derived from drawdown data (t) and recovery data (t′), respectively. Comparisons showed that t is equal to t′ when drawdown reaches a steady or quasi-steady state. Conversely, when the pump is turned off before reaching a quasi-steady state, t differs from t′. However, results also indicate the fact that a decent hydraulic travel time diagnosis can be obtained, especially for the cases when travel times are smaller than 15 s. Given the statistical results of Monte-Carlo simulations, as well as experience during pumping tests in the field with different scenarios, using the recovery data from 60 s of pumping duration, or extended pumping durations of 100 s or 200 s as a more conservative alternative, can replace the aquifer characterization based on drawdown data. The new inversion strategy not only has less data uncertainty and equivalent inversion accuracy, but also can greatly enhance the repeatability of field tests and reduce the environmental impact of long-term pumping tests
- …
