94 research outputs found

    Development of active microwave thermography for structural health monitoring

    Get PDF
    Active Microwave Thermography (AMT) is an integrated nondestructive testing and evaluation (NDT&E) method that incorporates aspects of microwave NDT and thermography techniques. AMT uses a microwave excitation to generate heat and the surface thermal profile of the material or structure under test is subsequently measured using a thermal camera (or IR camera). Utilizing a microwave heat excitation provides advantages over traditional thermal excitations (heat lamps, etc.) including the potential for non-contact, selective and focused heating. During an AMT inspection, two heating mechanisms are possible, referred to as dielectric and induction heating. Dielectric heating occurs as a result of the interaction of microwave energy with lossy dielectric materials which results in dissipated microwave energy and a subsequent increase in temperature. Induction heating is a result of induced surface current on conductive materials with finite conductivity under microwave illumination and subsequently ohmic loss. Due to the unique properties of microwave signals including frequency of operation, power level, and polarization, as well as their interaction with different materials, AMT has strong potential for application in various industries including infrastructure, transportation, aerospace, etc. As such, this Dissertation explores the application of AMT to NDT&E needs in these important industries, including detection and evaluation of defects in single- or multi-layered fiber-reinforced polymer-strengthened cement-based materials, evaluation of steel fiber percentage and distributions in steel fiber reinforced structures, characterization of corrosion ratio on corroded reinforcing steel bars (rebar), and evaluation of covered surface cracks orientation and size in metal structures --Abstract, page iv

    Local hyperthermia case study

    Get PDF
    Background: Prostate cancer is the second most common reason of death in men. Multidisciplinary therapy is the best treatment option, although, there is no common consent on optimal therapy for advanced prostate cancer.Case Presentation: The present study reports a case of 75 year-old man who had a huge heterogeneous soft tissue mass lesion with non-homogeneous enhancement consisted low attenuated foci occupying pelvis cavity and lower abdomen with loss of mesenteric fat and invasion to posterior bladder wall due to T4N1Mx prostate cancer. The patient was treated with adjuvant radiotherapy (RT) plus local hyperthermia (HT).Conclusion: This report shows the potential capability of HT application during RT. Radiotherapy with hyperthermia combination revealed a dramatic response in this case and after treatment it left the patient asymptomatic

    Biopolymer-based structuring of liquid oil into soft solids and oleogels using water-continuous emulsions as templates

    Get PDF
    Physical trapping of a hydrophobic liquid oil in a matrix of water-soluble biopolymers was achieved using a facile two-step process by first formulating a surfactant-free oil-in-water emulsion stabilized by biopolymers (a protein and a polysaccharide) followed by complete removal of the water phase (by either high- or low-temperature drying of the emulsion) resulting in structured solid systems containing a high concentration of liquid oil (above 97 wt %). The microstructure of these systems was revealed by confocal and cryo-scanning electron microscopy, and the effect of biopolymer concentrations on the consistency of emulsions as well as the dried product was evaluated using a combination of small-amplitude oscillatory shear rheometry and large deformation fracture studies. The oleogel prepared by shearing the dried product showed a high gel strength as well as a certain degree of thixotropic recovery even at high temperatures. Moreover, the reversibility of the process was demonstrated by shearing the dried product in the presence of water to obtain reconstituted emulsions with rheological properties comparable to those of the fresh emulsion

    Thermal enhancement effect on chemo-radiation of Glioblastoma multiform

    Get PDF
    Background: Hyperthermia plays a significant role in the chemo-radiotherapy effect in different malignancies. In this research, we treated Glioblastoma multform (GBM) patents with hyperthermia (HT) along with the chemoradiaton, in order to evaluate HT efficacy in terms of tumor volume changes, survival tme, and probability. Materials and Methods: Thirty-eight GBM patents were distributed into two groups identfied as chemoradiaton (CRT), and also CRT plus HT (CRHT). The Karnofsky Performance Status Scale (KPS) was done before, immediately and three months after treatments. Capacitve hyperthermia device was used at frequency of 13.56 MHz (Celsius 42+ GmbH, Germany) for HT one hour before the radiotherapy for 10-12 sessions. Patents in both groups underwent MR imaging (1.5 Tesla) before, 3 and 6 months after the treatments. Thermal enhancement factors (TEF) were atained in terms of clinical target volume changes, TEF(CTV), and survival probability (SP) or TEF(SP). Results: Age ranges were from 27-73 years (Mean=50) and 27-65 years (Mean=50) for CRT and CRHT groups, respectvely. For 53 and 47 of cases biopsy and partal resecton were accomplished in both groups, respectvely. Means and standard deviatons of tumor volumes were 135.42±92.5 and 58.4±104.1cm3before treatment in CRT and CRHT groups, respectvely, with no significant difference (P= 0.2). TEF(CTV) value was atained to be as 1.54 and 1.70 for three and six months after treatments, respectvely, TEF(SP) was also equal to the 1.90. Conclusion: HT enhanced the chemoradiaton effects throughout the patent survival probability and KPS. TEF may reflect the hyperthermia efficacy for a given radiaton dose. © 2020 Novin Medical Radiation Institute. All rights reserved

    A randomized, double-blind, placebo-controlled investigation of BCc1 nanomedicine effect on survival and quality of life in metastatic and non-metastatic gastric cancer patients

    Get PDF
    Background: Currently, the main goal of cancer research is to increase longevity of patients suffering malignant cancers. The promising results of BCc1 in vitro and vivo experiments made us look into the effect of BCc1 nanomedicine on patients with cancer in a clinical trial. Methods: The present investigation was a randomized, double-blind, placebo-controlled, parallel, and multicenter study in which 123 patients (30-to-85-year-old men and women) with metastatic and non-metastatic gastric cancer, in two separate groups of BCc1 nanomedicine or placebo, were selected using a permuted block randomization method. For metastatic and non-metastatic patients, a daily dose of 3000 and 1500 mg was prescribed, respectively. Overall survival (OS) as the primary endpoint and quality of life (measured using QLQ-STO22) and adverse effects as the secondary endpoints were studied. Results: In metastatic patients, the median OS was significantly higher in BCc1 nanomedicine (174 days 95% confidence interval (CI) 82.37-265.62) than in placebo (62 days 95% CI 0-153.42); hazard ratio (HR): 0.5 95% CI 0.25-0.98; p = 0.046. In non-metastatic patients, the median OS was significantly higher in BCc1 nanomedicine (529 days 95% CI 393.245-664.75) than in placebo (345 days 95% CI 134.85-555.14); HR: 0.324 95% CI 0.97-1.07; p = 0.066. The QLQ-STO22 assessment showed a mean difference improvement of 3.25 and 2.29 (p value > 0.05) in BCc1 nanomedicine and a mean difference deterioration of - 4.42 and - 3 (p-value < 0.05) in placebo with metastatic and non-metastatic patients, respectively. No adverse effects were observed. Conclusion: The findings of this trial has provided evidence for the potential capacity of BCc1 nanomedicine for treatment of cancer. Trial registration IRCTID, IRCT2017101935423N1. Registered on 19 October 2017, http://www.irct.ir/ IRCT2017101935423N1 © 2019 The Author(s)

    Models for structure-rheology of highly concentrated emulsions

    No full text
    Thesis (DTech (Chemical Engineering))--Cape Peninsula University of Technology, 2009.Highly concentrated emulsions (HCE) are classified as high internal phase ratio emulsions (or simply HIPRE), and the dispersed phase droplets are ranged In a hexagonal closely packed configuration. This closely packed configuration and the profound hydrodynamic interaction between neighbouring droplets induce mechanical interference between the droplets, thus prohibiting their free movement. Hence, while the highly concentrated emulsions consist of very low viscosity and inelastic components, they show gel-like behaviour with high elasticity and non-Newtonian flow response. It has been suggested in the literature that this behaviour originated from interfacial energy in terms of Laplace pressure. Therefore, the scaling of rheological properties with Laplace pressure is expected, but several publications show a deviation from this scaling behaviour. It seems that the source of deviation from this scaling is interdroplet interaction, which can contribute to the rheological behaviour of highly concentrated emulsions. The shear modulus of highly concentrated emulsions in the presence of interdroplet interaction was developed in this work. The prediction of model was verified by the data presented in the literature. It was shown that a small source of interdroplet interaction can result in deviation from scaling of shear modulus with Laplace pressure

    Design of a Microstrip Patch Antenna for Microwave Sensing of Petroleum Production Lines

    No full text
    In this paper, the design of a microstrip patch antenna for microwave sensing of sand production in petroleum pipelines is presented. Two antennas are designed in order to cover the entire sensing regime (gas to liquid including large percentages of brine) common to petroleum production lines. The antennas are designed to operate at ~5GHz. The antenna intended for sensing with low-loss fluids (gas or oil) is capable of ~4% bandwidth (&verbar;S11&verbar; \u3c -10 dB), and the antenna intended for sensing with high loss fluids (brine) is capable of ~7% bandwidth

    Sustainable cooling solutions for application in Western Cape Province, South Africa

    No full text
    The energy demand in building sectors for summer air-conditioning is growing exponentially due to global warming, increased living standards and occupant comfort demands throughout the last decades. Concerns over these environmental changes have begun shifting the emphasis from current cooling methods, to ‘sustainable strategies’ of achieving equally comfortable conditions in building interiors. Study of ancient strategies applied by vernacular architecture shows how the indigenously clean energies to satisfy the cooling need were used. One of the most important influences on vernacular architecture is the macro-climate of the area in which the building is constructed. Not only vernacular structure but also the recent development in solar and geothermal cooling technologies could be used for environmental control needs. Intelligent coupling of these methods as alternative design strategies could help developing countries, such as South Africa, toward sustainable development in air-conditioning of buildings
    corecore