49 research outputs found
Quantification of damage evolution in masonry walls subjected to induced seismicity
This paper aims to quantify the evolution of damage in masonry walls under induced seismicity. A damage index equation, which is a function of the evolution of shear slippage and opening of the mortar joints, as well as of the drift ratio of masonry walls, was proposed herein. Initially, a dataset of experimental tests from in-plane quasi-static and cyclic tests on masonry walls was considered. The experimentally obtained crack patterns were investigated and their correlation with damage propagation was studied. Using a software based on the Distinct Element Method, a numerical model was developed and validated against full-scale experimental tests obtained from the literature. Wall panels representing common typologies of house façades of unreinforced masonry buildings in Northern Europe i.e. near the Groningen gas field in the Netherlands, were numerically investigated. The accumulated damage within the seismic response of the masonry walls was investigated by means of representative harmonic load excitations and an incremental dynamic analysis based on induced seismicity records from Groningen region. The ability of this index to capture different damage situations is demonstrated. The proposed methodology could also be applied to quantify damage and accumulation in masonry during strong earthquakes and aftershocks too
4(2) 50 Case Study Dapsone Hypersensitivity Syndrome in a Leprosy Patient
ABSTRACT Introduction: Dapsone Hypersensitivity Syndrome (DHS) is a rare potentially fatal systemic idiosyncratic adverse reaction, with multiorgan involvement also known as sulphone syndrome which is particularly seen in leprosy patients who are on world health organization recommended multidrug therapy (WHO-MDT regimen). DHS is a variant of drug rash with eosinophilia and systemic symptoms (DRESS syndrome) caused by dapsone. Even though reaction common in the leprosy patients there is need such reporting to identify the most venerable patient pool. Case: Here we present a case of DHS developed after 25 days in a female patient with a history of PB-MDT regimen treatment, high grade intermittent fever associated with nausea, myalgia, headache since 20 days; swelling of face, bilateral lower limbs and erythematous rashes were observed all over the body since 4 days. She was presented with fever (102.2 0 F), posterior cervical and axillary lymphadenopathy and moderate bilateral lower limb pitting pedal edema was present. Multiple erythematous papules coalesced all over body predominantly involved on the face, trunk and extremities. The main laboratory data on admission were showed, hemoglobin: 9.6 g/dL; WBC: 14.6 x 10³/ µL; neutrophils: 48% mild left shift, lymphocyte: 20% reactive forms; eosinophils: 16%; increased serum levels of aspartate amino transferase, alanine transaminase and alkaline phosphatase. Patient was improved and discharged on treating with antipyretics, antibiotics, oral and topical corticosteroids and antihistamines
Ordered Arrays of SiGe Islands from Low-Energy PECVD
SiGe islands have been proposed for applications in the fields of microelectronics, optoelectronics and thermoelectrics. Although most of the works in literature are based on MBE, one of the possible advantages of low-energy plasma-enhanced chemical vapor deposition (LEPECVD) is a wider range of deposition rates, which in turn results in the possibility of growing islands with a high Ge concentration. We will show that LEPECVD can be effectively used for the controlled growth of ordered arrays of SiGe islands. In order to control the nucleation of the islands, patterned Si (001) substrates were obtained by e-beam lithography (EBL) and dry etching. We realized periodic circular pits with diameters ranging from 80 to 300 nm and depths from 65 to 75 nm. Subsequently, thin films (0.8–3.2 nm) of pure Ge were deposited by LEPECVD, resulting in regular and uniform arrays of Ge-rich islands. LEPECVD allowed the use of a wide range of growth rates (0.01–0.1 nm s−1) and substrates temperatures (600–750°C), so that the Ge content of the islands could be varied. Island morphology was characterized by AFM, while μ-Raman was used to analyze the Ge content inside the islands and the composition differences between islands on patterned and unpatterned areas of the substrate
Determination of hydroxyl groups in biorefinery resources via quantitative 31P NMR spectroscopy
The analysis of chemical structural characteristics of biorefinery product streams (such as lignin and tannin) has advanced substantially over the past decade, with traditional wet-chemical techniques being replaced or supplemented by NMR methodologies. Quantitative 31P NMR spectroscopy is a promising technique for the analysis of hydroxyl groups because of its unique characterization capability and broad potential applicability across the biorefinery research community. This protocol describes procedures for (i) the preparation/solubilization of lignin and tannin, (ii) the phosphitylation of their hydroxyl groups, (iii) NMR acquisition details, and (iv) the ensuing data analyses and means to precisely calculate the content of the different types of hydroxyl groups. Compared with traditional wet-chemical techniques, the technique of quantitative 31P NMR spectroscopy offers unique advantages in measuring hydroxyl groups in a single spectrum with high signal resolution. The method provides complete quantitative information about the hydroxyl groups with small amounts of sample (~30 mg) within a relatively short experimental time (~30-120 min)
Investigations On The Restoration And Seismic Enhancement Options For The Jaisedewal Temple After The Gorkha Earthquake In Nepal
Photoluminescence of ortho-bromobenzophenone
Phosphorescence spectra of crystalline ortho-bromobenzophenone (2-bromobenzophenone,
2BrBP) were measured from 1.6 K to room temperature. A cardinal emission mechanism crossover
occurs within this temperature range. At low temperature the phosphorescence spectrum is a
superposition of two similar sets of equidistant bands spaced by the C=O stretch frequency. We
ascribe these two sets to the emission of two different conformers, one of which is metastable and
do not manifest itself above approximately 70 K. Presence of two conformers is explained by the
fact that the 2BrBP molecule deforms considerably upon excitation. The emission from the stable
conformer survives up to approximately 140 K or even higher. At roughly 60 K and higher, another
type of emission reveals itself in the shape of a two very broad partly overlapping bands, which
gains in intensity with increasing temperature. Above 150 K only this two-hump feature is
observed in phosphorescence spectra. Additional phosphorescence experiments were carried out to
elucidate the nature of this spectrum, including phosphorescence measurements of 2BrBP in
ethanol solutions as well as time-resolved and varying-excitation-intensity measurements from
crystals. Based on results of all the experiments reported here and on our own single-crystal x-ray
structure data we conclude that the above two-band spectrum recorded near room temperature is
due to the emission of single-photon bimolecular triplet excimer formed by the carbonyl groups of
two neighbor 2-bromobenzophenone molecules. It is got the first time that a bimolecular excimer
has been observed and reliably identified in a benzophenone derivative solid
SERS substrates on the base of semiconductor self-assembled quantum dots Ge-on-Si nanostrustures to characterize inorganic microcrystals
SERS substrates on the base of semiconductor self-assembled quantum dots Ge-on-Si nanostrustures to characterize inorganic microcrystals
Assessment of Vibrational Spectroscopy Performance in Geographical Identification of Virgin Olive Oils: A World Level Study
7 Figuras.-- 5 TablasIn order to guarantee food integrity, testing methods should also include the tools needed to verify the geographical origin described on the label. In the particular case of virgin olive oil (VOO), regulatory bodies have yet to establish a standard for geographical identification. This manuscript describes a procedure based on Raman spectroscopy to identify the provenance of these oils based on a classification criterion (European vs non‐European VOOs). The sample collection is considered a relevant step in which multiple factors are taken into account (cultivar distribution, complexity of production in each location, new agricultural practices, and new/old cultivars). A total of 78 virgin olive oils collected around the world allow checking the classification accuracy of the model for identifying sample origin. The PLS‐model built around the Raman spectroscopic data is validated with a blind set of samples, and the results are evaluated in terms of false negative and false positive quality parameters. This study provides an analytical application to detect mislabeling and fraudulent practices related to the geographical provenance of virgin olive oils declared on the labels.
Practical Applications: The results of this study provide a robust mathematical model to assess the origin of virgin olive oils (EU vs non‐EU) based on spectroscopic data. Nowadays, the extensive knowledge of olive oil chemical composition has proven that this composition varies according to pedoclimatic conditions, while non‐targeted methods can be proposed in geographical traceability for their ability to analyze the chemical profile of samples. However, it was deemed necessary to conduct a study through a collaborative work initiative. Thus, this study provides a strict evaluation of Raman spectroscopy through a defined strategy for evaluating non‐targeted methods for geographical identification.The authors would like to thank Mr. Quentin Arnould from CRA‐W for the assistance in FT‐Raman analysis. The project has received funding from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement No. 613688 (FoodIntegrity).Peer reviewe