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91.
Lisa Hernqvist Åsa Fransson Gunnar Gustafson Ann Emmelin Magnus Eriksson Håkan Stille 《International Journal of Rock Mechanics and Mining Sciences》2009,46(3):439-449
The grouting results for a tunnel at a depth of 450 m in crystalline rock at Äspö HRL were studied. The aims were to investigate whether the methodology used resulted in a successful grouting design and producing a sufficiently dry tunnel, and whether grout penetration and inflow into the finished tunnel corresponded to the predictions. An analysis was made of data from an original cored borehole, drilled before the tunnel was constructed and mapped thoroughly with regard to fractures and transmissivities. The predicted inflow into the tunnel was calculated and found to be four times higher than the measured inflow. The latter was 5 l/min along the 70 m tunnel, considered to be a good result at the current depth. New cored control boreholes were drilled along a section of the tunnel. The inflow positions and quantities in these holes, and the positions of grout found in the corresponding cores, were compared with the data from the original borehole. It was found that at the predicted positions of larger fractures, grout was observed and there was no inflow, showing that these had been successfully sealed. At the predicted positions of small fractures, no grout was visible in the cores, and small inflows showed that the grout had not sealed these fractures. The results indicated that cement-based grout successfully sealed fractures down to a hydraulic aperture of about 50 μm but not below 30 μm. This concurs with the initial design aimed at sealing fractures larger than 50 μm. 相似文献
92.
Bergvall E Hedstrom E Bloch KM Arheden H Sparr G 《IEEE transactions on medical imaging》2008,27(8):1045-1053
93.
Gunnar Suchaneck Vinay S. Vidyarthi Marianne Reibold Alexander Deyneka Lubomir Jastrabik Gerald Gerlach Johannes Hartung 《Journal of Electroceramics》2008,20(1):17-20
Pb(Zr,Ti)O3 (PZT) thin films deposited on insulating ZrO2 buffered silicon wafer are intended to be employed for in-plane polarized piezoelectric MEMS devices. Multi-target reactive
sputtering system for large area deposition of in-situ crystallized PZT thin films and the ZrO2 buffer layer has been employed. The interface analysis of multilayer structures by high resolution transmission microscope,
X-ray diffraction, optical refraction, and absorption spectra studies has been presented. At a substrate temperature of 520°C
and excess lead deposition condition, the formation of a PZT superstructure has been revealed. The substrate temperature of
580°C leads to the crystallization of PZT directly into a single phase perovskite crystal structure. A pronounced Urbach behavior
in our PZT thin films has been observed by optical absorption studies. The surface roughness of PZT films deposited on a ZrO2 buffer layer is much higher than that on conducting platinized silicon wafer. 相似文献
94.
Mette Schmedes Asker Daniel Brejnrod Eli Kristin Aadland Pia Kiilerich Karsten Kristiansen Hlne Jacques Charles Lavigne Ingvild Eide Graff
yvin Eng Asle Holthe Gunnar Mellgren Jette Feveile Young Ulrik Krmer Sundekilde Bjrn Liaset Hanne Christine Bertram 《Molecular nutrition & food research》2019,63(1)
95.
96.
97.
Jasmina Ga
anin Jana Hedrich Stefanie Sieste Gunnar Glaßer Ingo Lieberwirth Corinna Schilling Stephan Fischer Holger Barth Bernd Knll Christopher V. Synatschke Tanja Weil 《Advanced materials (Deerfield Beach, Fla.)》2019,31(2)
The synthesis of hybrid hydrogels by pH‐controlled structural transition with exceptional rheological properties as cellular matrix is reported. “Depsi” peptide sequences are grafted onto a polypeptide backbone that undergo a pH‐induced intramolecular O–N–acyl migration at physiological conditions affording peptide nanofibers (PNFs) as supramolecular gelators. The polypeptide–PNF hydrogels are mechanically remarkably robust. They reveal exciting thixotropic behavior with immediate in situ recovery after exposure to various high strains over long periods and self‐repair of defects by instantaneous reassembly. High cytocompatibility, convenient functionalization by coassembly, and controlled enzymatic degradation but stability in 2D and 3D cell culture as demonstrated by the encapsulation of primary human umbilical vein endothelial cells and neuronal cells open many attractive opportunities for 3D tissue engineering and other biomedical applications. 相似文献
98.
Mass Spectrometric Analysis of Cerebrospinal Fluid Ubiquitin in Alzheimer's Disease and Parkinsonian Disorders 下载免费PDF全文
Simon Sjödin Oskar Hansson Annika Öhrfelt Gunnar Brinkmalm Henrik Zetterberg Ann Brinkmalm Kaj Blennow 《Proteomics. Clinical applications》2017,11(11-12)
1 Purpose
Dysfunctional proteostasis, with decreased protein degradation and an accumulation of ubiquitin into aggregated protein inclusions, is a feature of neurodegenerative diseases. Identifying new potential biomarkers in cerebrospinal fluid (CSF) reflecting this process could contribute important information on pathophysiology.2 Experimental design
A developed method combining SPE and PRM‐MS is employed to monitor the concentration of ubiquitin in CSF from subjects with Alzheimer's disease (AD), Parkinson's disease (PD), and progressive supranuclear palsy (PSP). Four independent cross‐sectional studies are conducted, studies 1–4, including controls (n = 86) and participants with AD (n = 60), PD (n = 15), and PSP (n = 11).3 Results
The method shows a repeatability and intermediate precision not exceeding 6.1 and 7.9%, respectively. The determined LOD is 0.1 nm and the LOQ range between 0.625 and 80 nm . The CSF ubiquitin concentration is 1.2–1.5‐fold higher in AD patients compared with controls in the three independent AD‐control studies (Study 1, p < 0.001; Study 2, p < 0.001; and Study 3, p = 0.003). In the fourth study, there is no difference in PD or PSP, compared to controls.4 Conclusion and clinical relevance
CSF ubiquitin may reflect dysfunctional proteostasis in AD. The described method can be used for further exploration of ubiquitin as a potential biomarker in neurodegenerative diseases. 相似文献99.
Metal contamination at a wood preservation site: characterisation and experimental studies on remediation 总被引:2,自引:0,他引:2
Bhattacharya P Mukherjee AB Jacks G Nordqvist S 《The Science of the total environment》2002,290(1-3):165-180
The aim of this investigation was to determine the occurrence of As, Cu, Cr and Zn in the soil at an abandoned wood preservation unit and to examine some possible extractants for the contaminants in the soil. The mean As content of the contaminated surface soils (0-10 cm) was 186 mg kg(-1), where as the mean concentrations of Cu, Cr and Zn in soils from the contaminated area were 26, 29 and 91 mg kg(-1), respectively. The elevated As content in the mineral soils is related to adsorption of inorganic As phases in the fine grained fractions, which are characterised by large surface area and high positive surface charge under the current acidic conditions. Cu and Cr were found to be rather mobile, which is reflected in their lower abundance in soils and significant accumulation in sediments in the drainage leaving the area. The fine fraction of the soil (<0.125 mm) has an average metal content increased by nearly 34% as compared to the <2-mm fraction conventionally used for the analysis and assessment of soil contamination. The <2-mm fraction constitutes approximately 65% of the total weight while the fine fraction (<0.125 mm) constitutes approximately 10%. These facts, taken together, are essential for the choice of remediation measures. Oxalate solutions have been tested as extractants for soil remediation. Dark acid oxalate extraction dissolves the amorphous Al- and Fe-oxides and hydroxides and mobilises the adsorbed inorganic As species. Oxalate also acts as a ligand for the cationic heavy metals, releasing them from exchangeable sites. With a three-step sequential leaching, up to 98-99% of the metals could be removed. At lower concentrations and higher pH, the leaching decreased to approximately 70%. 相似文献
100.
Lundberg Ulf; Dohns Ingela Elfsberg; Melin Bo; Sandsj? Leif; Palmerud Gunnar; Kadefors Roland; Ekstr?m Maria; Parr Deirdre 《Canadian Metallurgical Quarterly》1999,4(3):245
This study examined psychological and physiological stress, as well as muscle tension and musculoskeletal symptoms, among 72 female supermarket cashiers. Stress levels were found to be significantly elevated at work, as reflected in the catecholamines, blood pressure, heart rate, electromyographic (EMG) activity, and self-reports. Fifty cashiers (70%) suffering from neck-shoulder pain (trapezius myalgia) were found to have higher EMG activity at work and reported more tension after work. Women who kept a diary for 1 week and reported more musculoskeletal pain (above the median) were older, had higher blood pressure, and reported more work stress and psychosomatic symptoms. The elevated stress levels at work are consistent with data from workers involved in other types of repetitive tasks and can be important for the high prevalence of neck and shoulder symptoms among the cashiers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献