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MEASUREMENT OF AIR STREAM VELOCITY PROFILES, GENERATED BY FIRE PROTECTION UNITS MOBILE FANS
Get PDFMobile positive pressure fans are an essential tool used during rescue operations during fires inside buildings. Due to the nature of the use of these devices, it is very important that the parameters that determine their effectiveness are properly selected and verified. One of the most important parameters determining their effectiveness is the volume flow rate of the air stream. In order to reliably evaluate the performance of fans, tests should be conducted on the basis of appropriately selected test methodologies. With regard to flow rate tests, it is important that the tests are conducted under conditions that reflect the actual use of mobile fans (open-flow tests). This paper presents the design, manufacturing, and functionality of an innovative stand for evaluating the velocity profile characteristics (and volume of the flow stream) of an air stream generated by mobile fans. The paper also presents the results of a fan that is commonly used during rescue operations. The results of the tests confirmed that the fan positioning parameters (i.e. the distance in front of the door opening and the inclination angle of the impeller) have a dominant influence on the stream flow rate, pumped into the ventilated cubature. Depending on the setup configuration of the fan unit, the discharge flow rate varied from 12087.6 m3/h to 42269.3 m3/h
STATISTICAL EVALUATION OF ULTRASONIC SIGNAL DIFFERENCES DEPENDENT ON THE ANGLE OF TILT OF THE REFLECTING SURFACE
Get PDFThis paper deals with the statistical evaluation of the variation of amplitudes measured on ultrasonic transducers, which were parabolic displaced. The reflecting surface was used metal plate of dimensions 245x220x1 millimetres. The distance of the ultrasonic transmitter from the reflection normal was set conically to 190 mm. The distance of the ultrasonic of the transducers from the reflection normal was 900 mm. At the significance level of α = 0.05, it was shown that there is a statistically significant decrease in absolute amplitude with increasing angle of the reflection normal on the ultrasound transducers. The critical angle was set to be 30°, which supports the chosen angular limit at the -6 dB attenuation band for the ultrasonic transducer used. Significant differences in the amplitudes of the ultrasonic signals give an indication of the direction of tilt of the reflecting surface. The statistically observed differences between the ultrasonic signal amplitudes are more indicative than the attenuation criteria of -3 dB and -6 dB, respectively. The mean values of the signal amplitudes were determined by arithmetic averaging over four repetitions of the experiment. The normality of the distribution of the detected signal amplitudes was verified at a significance level of α = 0.05 by the Shapiro-Wilk test
STUDY ON THE SUBSTRUCTURAL EVOLUTION OF AA3104 ROLLED SHEET DURING THERMAL TREATMENTS
Get PDFThe substructure of the rolled sheets plays a significant role as well as grain structure in the control of mechanical properties. The features that consist the substructure are prone to significant alterations throughout the production process and they require high-magnification and high-resolution analysis. . The present paper focuses on the study of the substructural evolution of a cold-rolled AAA3104 sheet during recovery and recrystallization thermal treatments. The results are correlated to the respective r- values and subgrain boundaries properties. The optimal behavior regarding formability was observed in the partially recrystallized sample (H28) accompanied by the presence of ≈14% subgrain angle boundaries (2-5o misorientation) and comparable recrystallization and deformation texture components
BIOMEDICAL APPLICATION OF LASER-INDUCED TISSUE OXYGENATION
Get PDFThe results of investigation of laser-induced photodissociation of oxyhemoglobin in cutaneous blood vessels and its role in biomedical processes are presented. We propose a new method for determination an individual response to the effect of laser radiation. It is shown that in order to make the phototherapy methods really efficient one has to control the oxygen concentration in tissue keeping it at the necessary level. Novel method of optical "dosimetry" based on using the changes oxygen concentration in tissue as feedback signal for optimization therapeutic effect of low intensity laser radiation is developed
TEMPORAL RESOLUTION IMPROVEMENT IN DYNAMIC SPECKLE ANALYSIS
Get PDFDynamic speckle imaging is effective approach for visualization of areas of faster or slower micro- changes on a 3D object surface by analysis of speckle patterns formed on this surface under laser illumination. A 2D distribution of a statistical parameter related to the measured speed of changes is built as a map of activity. The map entries strongly fluctuate from point to point even when the speed is constant in the observed area. The relevant information is buried in a signal-dependent noise, which depends on (1) activity, and (2) ratio between the time of acquisition of the speckle patterns in the sequence and the temporal correlation radius of the process. The time of acquisition gives the temporal resolution of the method. In order to improve this resolution, we studied acquisition at time interval between the patterns that is much shorter than the temporal correlation radius of intensity fluctuations caused by the underlying processes in the tested object
CRITICAL FACTORS FOR LEVERAGING TECHNOLOGY TRANSFER FROM A TECHNOLOGY INTERFACE CENTER TO THE INDUSTRIAL ECOSYSTEM: THE CASE STUDY OF A METALLOGRAPHY LABORATORY
Get PDFThis paper aims at identifying and empirically evaluating the critical success factors for technology transfer practices (TTP) from the Technology Interface Center (TecIC) dedicated to the metalworking industry into the industrial and manufacturing ecosystem in the Portuguese context based on a case study from a metallography laboratory. The authors will explore the rationale and practical implications for TTP in four vectors: i) technology adoption and technological outputs adoption by the industrial ecosystem; ii) networks, standardization, and knowledge creation; iii) lifelong learning/training and team capacitation; iv) industrial, academic and TecIC ecosystems interaction and knowledge and outputs transfer. This work calls attention for the central role of support and development that infrastructures such has technology interface centers play in accelerating technology transfer practices to the industrial ecosystem, especially in small and medium sized enterprises or highly differentiated organizations. The adoption by the industrial ecosystem of new or renewed processes and practices are also mediated and potentiated by the differentiated access to knowledge networks, access to technology, and technology mediated outputs such as the one promoted by TecIC
SOME BIOLOGICAL ACTIVITIES OF ASPARAGUS ACUTIFOLIUS L.
Get PDFThis study was aimed to determine the inhibition effect of wild asparagus extracts prepared with different solvents (water-ethanol-methanol) on the acetylcholinesterase (AChE) enzyme. In addition, antioxidant activities of plant extracts with DPPH and ABTS radical scavenging methods, and antibacterial activities against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Enterobacter faecalis bacteria by disc diffusion method were investigated. The half-maximal inhibitory concentration (IC50) values on the AChE enzyme were determined between 0.93 – 5.46 mg/mL for all of the extracts. The most effective extract for AChE enzyme was determined as methanol extract. Moreover, all extracts of wild asparagus were found to scavenge both DPPH and ABTS radicals with quite strong activity. In addition, it has been observed that all extracts of wild asparagus have an effective antibacterial activity on all bacteria. It was also determined that their great potential as antibacterial agents and antioxidant molecules of wild asparagus make them important candidates for pharmaceutical applications like anticholinesterase drugs or starter compounds for synthesizing more effective AChE inhibitors
HEAVY METAL ACCUMULATION AND CHEMICAL COMPOSITION OF THYMUS PULEGIOIDES ESSENTIAL OF GROWN ON SERPENTINE SOILS IN BULGARIA
Get PDFThis study investigated the heavy metal concentrations and chemical compositions of the essential oils of Thymus pulegioides (Lamiaceae), growing on serpentine soils in the Eastern Rhodopes Mountains, Bulgaria. Elevated Ni content in soils does not affect the development of Thymus pulegioides and the quality and quantity of oil obtained from it. Forty-two components representing 98.38- 98.48% of the total oil were identified. The major compounds were determined β-caryophyllene (14.15-15.54%), germacrene D(16.55-17.11%), Sabinene (10.40-11.54%), caryophyllene oxide (8.41-9.65%), cis-beta- ocimene (6.62 -6.91%), trans-beta-ocimene (5.09- 5.32%), (-)- spathulenol (4.34 - 6.54%), α-cadinol (2.06-5.51%), β-selinene (3.15- 3.30%), δ-cadinene (2.07-2.17%), α-humulene (1.95-2.04%), and β- bourbonene (1.58-1.65%) in thyme oils. Thymus pulegioides can be considered as “accumulator plant”, containing high metal concentrations in the aboveground biomass. Concentrations for toxic elements (Ni and Cr) in herbs were higher than the permissible limits for consumption. The strict control of marketed herbs for toxic metal content, and people should be informed about the risk of collecting and consuming herbs from serpentine soils Thymus pulegioides found on serpentine soils are recommended to be collected only for pharmaceutical purposes
THE EFFECT OF ORGANIC FERTILIZERS ON THE GRASSLAND BIOMASS
Get PDFThe aim of this study was to assess the effects of organic fertilizers (cow manure + dung water, slurry) applied in different annual doses of nitrogen (54 kg/ha; 84 kg/ha; 120 kg/ha) according to 3 different intensities of grassland utilization (extensive – 2 cuts per year, medium intensive – 3 cuts per year, intensive – 4 cuts per year) on percentage of plant functional groups (grasses, legumes, forbs), dry matter yield, and forage quality. The study was performed as a small-plot trial over 7 years on moderately moist grassland in the Czech Republic. The proportion of legumes was significantly higher in the fertilization treatments with cow manure + dung-water combined with medium intensive utilization and intensive utilization. Fertilization significantly increased dry matter yields compared to unfertilized controls. Extensive grassland utilization significantly decreased the energy value. Our findings suggest that medium intensive and intensive grassland utilization using organic fertilization which correspond to annual doses of nitrogen of 84 kg/ha and 120 kg/ha, are the most suitable for animal nutrition
PUMPKIN USED IN OBTAINING GLUTEN FREE BAKERY PRODUCTS
Get PDFThe incidence of metabolic diseases among the active population has an upward trend, which requires the diversification of the assortment range of gluten free products. The developed an innovative technology for obtaining gluten-free products with organic pumpkin pulp meets the required of a consumers segment, with gluten intolerance. Pumpkin is an ingredient used in Romanian gastronomy, and not only, in certain periods of the year, respectively in the winter season, and for this reason we recommendation integration in products with added value and functional role. Pumpkin is a vegetable rich in β-carotene, carbohydrates, dietary fiber, etc., with special sensory properties agreed by the Romanian consumers, with a low caloric content. We also aim to present the different technology and formula that are currently used to obtain foods product with pumpkin and the importance for health and diet