In-field Measurements Research Articles

Energy, comfort and indoor air quality in nursery and elementary school buildings in the cold climatic zone of Greece

Schools are the most suitable type of building for the application of energy efficiency and good indoor air quality measures. This is justified by the fact that such measures can promote sustainability to the future citizens, and even more, ensure a comfortable and healthy environment for educational purposes. Unfortunately, in practice school buildings face the same, or even more intense, energy performance and indoor air quality problems as any other building. The purpose of this study is to investigate the energy efficiency, thermal environment and indoor air quality in public nursery and elementary school buildings in the city of Kozani, located at the cold climatic zone of Greece. The survey, conducted both by in-field measurements and by questionnaires, reveals the main parameters affecting the overall performance of the investigated buildings. The problematic building envelope, the improper control of heating and lighting systems, the absence of proper legislative measures and, above all, the lack of interest concerning the efficiency of such buildings are the main factors in the reported efficiency.

Catalytic Efficiency of Iron(III) Oxides in Decomposition of Hydrogen Peroxide: Competition between the Surface Area and Crystallinity of Nanoparticles

Various iron(III) oxide catalysts were prepared by controlled decomposition of a narrow layer (ca. 1 mm) of iron(II) oxalate dihydrate, FeC(2)O(4).2H(2)O, in air at the minimum conversion temperature of 175 degrees C. This thermally induced solid-state process allows for simple synthesis of amorphous Fe(2)O(3) nanoparticles and their controlled one-step crystallization to hematite (alpha-Fe(2)O(3)). Thus, nanopowders differing in surface area and particle crystallinity can be produced depending on the reaction time. The phase composition of iron(III) oxides was monitored by XRD and (57)Fe Mössbauer spectroscopy including in-field measurements, providing information on the relative contents of amorphous and crystalline phases. The gradual changes in particle size and surface area accompanying crystallization were evaluated by HRTEM and BET analysis, respectively. The catalytic efficiency of the synthesized nanoparticles was tested by tracking the decomposition of hydrogen peroxide. The obtained kinetic data gave an unconventional nonmonotone dependence of the rate constant on the surface area of the samples. The amorphous nanopowder with the largest surface area of 401 m(2) g(-1) revealed the lowest catalytic efficiency, while the highest efficiency was achieved with the sample having a significantly lower surface area, 337 m(2) g(-1), exhibiting a prevailing content of crystalline alpha-Fe(2)O(3) phase. The obtained rate constant, 26.4 x 10(-3) min(-1) (g/L)(-1), is currently the highest value published. The observed rare catalytic phenomenon, where the particle crystallinity prevails over the surface area effects, is discussed with respect to other processes of heterogeneous catalysis.

Study of ${\rm Sm}_{\rm x}{\rm Zr}_{1-{\rm x}}{\rm O}_{\rm y}$ Buffer Layer and Its Effects on YBCO Properties

Biaxially textured Sm <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> Zr <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1-x</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">y</sub> (SZO) thin films have been grown directly on an ion beam assisted deposited (IBAD) MgO template, without using an intermediate homoepitaxial MgO layer. SZO buffer layers were deposited using reactive magnetron sputtering of a Sm (50 at.%)-Zr (50 at.%) alloy target. The SZO texture is similar to that of the MgO template. Epitaxial YBCO films, ~1mum-thick, grown by pulsed laser deposition on SZO buffered coated conductors have high critical current densities. The in-field measurements indicate that superconducting samples with SZO as buffer are as good as STO/homoepitaxial MgO buffered samples. These results demonstrate that SZO is an appropriate buffer for the fabrication of low cost YBCO/IBAD MgO coated conductors with excellent transport properties.

${\rm TmBa}_{2}{\rm Cu}_{3}{\rm O}_{7-{\rm x}}$ Superconducting Thin Films Grown by Pulsed Laser Deposition

TmBa2Cu3O7 - x films which is one of the (Rare earth)Ba2Cu3O7 - x high temperature superconductors with small ionic radius of rare earth element, were deposited on STO (100) single crystal substrates and Y2O3/YSZ/CeO2 buffered metal substrates by pulsed laser deposition. The Jc (77 K) and the value of onset of Tc TmBCO thin film on STO substrate was 4.5 MA/cm2 and 86 K, respectively. The of Jc TmBCO coated conductor on metal substrate was 1 MA/cm2 . In-field property measurement was carried out at temperatures between 10 K and 77 K in magnetic filed up to 6 T in PPMS system. This is the first report, to the best of our knowledge, of TmBCO thin films and coated conductors with TmBCO film as the superconducting layer which have critical current densities at 77 K of 4.5 MA/ cm2 and 1 MA/cm2 , respectively. The superconducting properties of TmBCO films and the possibility of using TmBCO film as the superconducting layer of the HTS coated conductor, were investigated.

Anisotropy and strength of vortex pinning centers in YBa2Cu3O7−x coated conductors

An experimental powerful methodology is proposed to evaluate and quantify the anisotropy and strength of the different pinning contributions of YBa2Cu3O7−x coated conductors by combining angular dependent in-field critical current measurements in the whole temperature range. A clear separation between isotropic and anisotropic pinning centers and a further classification into weak and strong pinning centers are performed. These analyses envision to establish a correlation between defect microstructure and critical currents which is essential for artificial engineering high-performance nanostructured coated conductors.

Engineered reactive cosputtered SmxZr1–xOythin films as buffer layers for YBa2Cu3O7−δcoated conductors

This study shows that biaxially textured SmxZr1−xOy(SZO) with a wide range of compositions (0.06 &lt;x&lt; 0.75) can be grown directly on ion-beam-assisted deposition (IBAD) MgO template using reactive cosputtering. The SZO crystal structure can be changed, and the lattice parameter can be tailored (from 5.23 to 5.49 Å) by changing the composition. We have developed a simplified high-temperature superconducting coated conductor using SZO as the buffer layer. YBa2Cu3O7−δ(YBCO) films grown by pulsed laser deposition on the SZO buffered IBAD MgO have self-field critical current densities (Jc) in the 2–4 MA/cm2range. The in-field measurements demonstrate that high-quality YBCO films can be grown on SZO buffered IBAD MgO. The present results are especially important because they were obtained on coated conductors with the simpler architecture by eliminating the additional homoepitaxial layer of MgO. This translates in faster production and lower manufacturing cost.

Design improvement of screw pump power sources for hydraulic elevators to reduce noise emissions

Three-screw pumps are often used as the pressure power source in hydraulic elevators. In some cases the pump and the motor are both submerged in the oil tank. This solution improves the cooling of the motor and the noise emission is low. In the case of big plants, the pump and the motor are both outside of the oil tank. With this layout, the noise emission of the pump cannot be disregarded, especially if the pump is used in civil building. In this paper first experimental tests on the noise emission of the pump in real conditions are presented. They were made using in-field measurements by means of sound intensity. Then, a theoretical study is presented on the possibility of reducing the quasi-impulsive load components, which act on the rotors of the three-screw pumps in the rotational axial direction. These forces can be related to the noise emission of the pump. The analysis is carried out by the systematic variation of one of the design parameters of the rotors, i.e. the semi-amplitude of the threaded zone of the screws, by using the analytical tools previously set-up for the study of the dynamic loads on the standard rotors. Finally, it is shown that a suitable choice of this design parameter on one hand allows cancellation of the quasi-impulsive load, on the other hand it has a positive effect on the radial loads.

Theoretical and Experimental Analysis of a Continuous-Blade Cutting System for Leafy Vegetables

To address the high costs associated with maintaining current reciprocating cutter bars used for harvesting spinach, a project was initiated to develop a lower-cost bandsaw cutting system. A model of the stresses generated in the saw blade under several loading scenarios was developed and used to evaluate the potential for fatigue failure with different support pulley and blade designs. For hardened steel blades, fatigue failure does not seem likely for pulley diameters equal to or greater than 300 mm. Torsional stiffness of a wide-span blade was modeled and used to determine the critical in-plane feed force exerted by the crop above which the blade will buckle. Laboratory tests with an instrumented bandsaw blade testing apparatus confirmed the predictions from the stability model that the critical forces necessary to induce buckling are low. The effects of blade thickness and tension on stability were examined and indicated that the resistance to buckling could be improved with increasing thickness and tension at the expense of fatigue life. For spans greater than 1.5 m, the blade tension required to prevent buckling was not practical, which suggested that the blade must be supported across the cutting width in order to achieve the required forces for cutting. A prototype bandsaw-type harvester was developed that included a continuous polymer blade guide to prevent blade twisting and buckling. Field capacity averaged 1.6 ha/h, corresponding to a throughput capacity in excess of 26 Mg/ha in spinach grown for processing. In-field recovery measurements and an N-way analysis of variance revealed no significant difference in harvest loss between semi-Savoy and smooth leaf spinach varieties. On average, harvest loss was about 5% of the commercial yield; approximately 1% of this loss was attributed to the harvester cutting mechanism as leaves still attached to the spinach crown. The remaining losses were significantly higher, consisting of loose leaves cut by the bandsaw but not gathered by the intake conveyor.

Environmental geophysics mapping salinity and water resources

Salinity and fresh water are two sides of the same coin, most conveniently measured by electrical conductivity; they can now be mapped rapidly in three dimensions using airborne electromagnetics (AEM). Recent developments in the calibration of airborne data against in-field measurements and additional information from radiometrics, magnetics and digital elevation models lend new insights into salinity, groundwater flow systems and water resources. Freshwater resources can be mapped, and salinity risk and the outcome of management interventions may be forecast, on the basis of the specific architecture of complete groundwater flow systems-enabling practical, cost-effective protection and development of water resources.

Negligible influence of domain walls on the magnetocaloric effect inGdPt2

Resistivity, magnetoresistance, magnetization, and in-field heat capacity measurements were performed of the $\mathrm{Gd}{\mathrm{Pt}}_{2}$ intermetallic compound. The magnetocaloric parameters $\ensuremath{\Delta}{T}_{\mathit{ad}}$ and $\ensuremath{-}\ensuremath{\Delta}S$ were derived from in-field heat capacity data. Comparison has been made between the magnetocaloric effect $\ensuremath{-}\ensuremath{\Delta}S$ and difference in resistivity $\ensuremath{-}\ensuremath{\Delta}\ensuremath{\rho}\phantom{\rule{0.3em}{0ex}}[=\ensuremath{\rho}(H)\ensuremath{-}\ensuremath{\rho}(0)]$ as a function of temperature. There is distinct difference in the temperature dependence of $\ensuremath{-}\ensuremath{\Delta}S$ and $\ensuremath{-}\ensuremath{\Delta}\ensuremath{\rho}$ below the ferromagnetic transition temperature. However, after removing the domain wall contribution from $\ensuremath{-}\ensuremath{\Delta}\ensuremath{\rho}$, the natures of the $\ensuremath{-}\ensuremath{\Delta}S$ and $\ensuremath{-}\ensuremath{\Delta}\ensuremath{\rho}$ dependence as a function of temperature are similar. Our observation indicates that the domain wall contribution in the magnetocaloric effect is negligible in spite of the fact that it has a significant contribution in magnetotransport.

Air quality in a commercial truck cabin

A survey and in-field measurements were undertaken to examine air quality in truck cabins. Preliminary survey results indicated that 99% of the truck drivers opened their windows for air while driving and they believed that the air was fresh. Field measurements showed that the concentrations of CO, CO 2, and NO 2 in the truck cabin during a two month monitoring period were lower than their respective recommended values. However, thermal comfort level, as indicated by temperature and relative humidity, was out of the recommended level for 93% of the measurement period. Moreover, readings for PM2.5 were within the range of 66–835 μg/m 3 which were 1–13 times the recommended value.

Crop Simulation and Crop Evapotranspiration for Irrigation Management of Spinach

Improving irrigation water management for crop production is becoming increasingly important in South Texas as the water supplies shrink and competition with urban centers in the region grows. Crop simulators and crop evapotranspiration (ET) are appealing methods for estimating crop water use and irrigation requirements because of the low investment in time and dollars required by on-site (in-field) measurement of soil and/or crop water status. We compared the effectiveness of the Crop.m.an/EPIC crop simulator and Crop-ET approaches estimating the crop water use for irrigation scheduling of spinach. In-ground weighing lysimeters were used to measure real-time spinach water use during the growing season. We related the water use of the spinach crop to a well-watered reference grass crop to determine crop coefficients (Kc) to assist in predicting accurate crop needs using available meteorological data. In addition, we ran several simulations of CropMan to evaluate the best management for growing spinach under limited water availability. Results show the possibility of saving about 61 to 74 million m3 of water per year in the 36,500 ha of irrigated farms of the Edwards aquifer region if proper irrigation management techniques are implemented in conjunction with the newly developed decision support systems. We discuss the implications of the use of these technologies for improving the effectiveness of irrigation and for reducing irrigation water requirements in South Texas.

Field-induced linear magnetoelastic coupling in multiferroicTbMnO3

We have used in-field neutron and X-ray single crystal diffraction to measure the incommensurability &#948; of the crystal and magnetic structure of multiferroic TbMnO3 . We show that the flop in the electric polarization at the critical field HC, for field H along the a&#8722; and b&#8722;axis coincides with a 1st order transition to a commensurate phase with propagation vector &#954; = (0, 1/4, 0). In-field X-ray diffraction measurements show that the quadratic magneto-elastic coupling breaks down with applied field as shown by the observation of the 1st harmonic lattice reflections above and below HC . This indicates that magnetic field induces a linear magneto-elastic coupling. We argue that the commensurate phase can be described by an ordering of Mn-O-Mn bond angles.

Determination of 235U enrichment with a large volume CZT detector

Room-temperature CdZnTe and CdTe detectors have been routinely used in the field of Nuclear Safeguards for many years [Ivanov et al., Development of large volume hemispheric CdZnTe detectors for use in safeguards applications, ESARDA European Safeguards Research and Development Association, Le Corum, Montpellier, France, 1997, p. 447; Czock and Arlt, Nucl. Instr. and Meth. A 458 (2001) 175; Arlt et al., Nucl. Instr. and Meth. A 428 (1999) 127; Lebrun et al., Nucl. Instr. and Meth. A 448 (2000) 598; Aparo et al., Development and implementation of compact gamma spectrometers for spent fuel measurements, in: Proceedings, 21st Annual ESARDA, 1999; Arlt and Rudsquist, Nucl. Instr. and Meth. A 380 (1996) 455; Khusainov et al., High resolution pin type CdTe detectors for the verification of nuclear material, in: Proceedings, 17th Annual ESARDA European Safeguards Research and Development Association, 1995; Mortreau and Berndt, Nucl. Instr. and Meth. A 458 (2001) 183; Ruhter et al., UCRL-JC-130548, 1998; Abbas et al., Nucl. Instr. and Meth. A 405 (1998) 153; Ruhter and Gunnink, Nucl. Instr. and Meth. A 353 (1994) 716]. Due to their performance and small size, they are ideal detectors for hand-held applications such as verification of spent and fresh fuel, U/Pu attribute tests as well as for the determination of 235U enrichment. The hemispherical CdZnTe type produced by RITEC (Riga, Latvia) [Ivanov et al., 1997] is the most widely used detector in the field of inspection. With volumes ranging from 2 to 1500 mm 3, their spectral performance is such that the use of electronic processing to correct the pulse shape is not required. This paper reports on the work carried out with a large volume (15×15×7.5 mm 3) and high efficiency hemispherical CdZnTe detector for the determination of 235U enrichment. The measurements were made with certified uranium samples whose enrichment ranging from 0.31% to 92.42%, cover the whole range of in-field measurement conditions. The interposed shield thickness varied from 2 mm of aluminium to 16 mm of steel. The results showed that, despite the detector instability, it is possible to achieve a good precision within a short counting time and for low enriched uranium, even when thick shielding is interposed between the source and the detector.

Experimental comparison of FORC and remanent Preisach diagrams

First-order reversal curve (FORC) and remanence-based Preisach diagrams are alternative ways of determining the Preisach distribution of a sample, which incorporates information about the coercivity spectrum and the distribution of interactions and self-demagnetizing fields. We compare results of the two methods for well-characterized synthetic and natural samples containing single-domain (SD) and pseudo-SD (PSD) magnetite, maghemite, titanomagnetite and titanomaghemite. The greater time requirements of remanence as opposed to in-field measurements limited our Preisach diagrams to a few hundred points, compared to several thousand points for the corresponding FORC diagrams. Only minimal smoothing could be applied in order to limit the regions near the axes of the diagrams in which function values must be extrapolated. In spite of these restrictions, we find excellent agreement between the essential features of the distributions determined by the two methods. The main features, the location and spreading of the distribution peak, are very consistent. However, the low-coercivity part of the Preisach distribution is sometimes poorly resolved or not imaged at all for remanence-only measurements. Features in this region can be diagnostic of PSD and multidomain (MD) grains. The essential agreement between our FORC and Preisach diagrams in the region where they overlap justifies using the much faster FORC routine instead of traditional remanence-based Preisach methods to determine the Preisach distribution of palaeomagnetic samples without strong interactions. We propose a symmetric FORC protocol that would permit separation of the irreversible and reversible parts of the Preisach distribution. The irreversible part is what is determined by remanence-only methods and what is desired for characterization of the remanence behaviour of palaeomagnetic samples. The reversible part is most significant in detecting MD behaviour and screening out samples containing large PSD and MD grains.

Preservation of the artistic heritage within the seat of the Chancellorship of the University of Palermo: A proposal on a methodology regarding an environmental investigation according to Italian Standards

The correct maintenance of artworks of historical and artistic value requires a wide and detailed analysis of all the information relevant for preserving them, such as identification of the main deterioration factors, knowledge of the climatic history of the object, set-up of measuring methods and statistics of the guide parameters, and definition of a set of recommended environmental aspects to be controlled within a stable climate condition linked to the particular kind of object or its surface. In Italy, the basic laws UNI 10829 and UNI 10969 impose a reference methodology for the in-field measurement and data analysis. This paper reports the first results of a measuring campaign, carried out according to the indications of the aforesaid standards, aimed at the investigation of the environmental conditions of the wooden ceilings in two rooms of “Palazzo Steri”, an ancient building in the city of Palermo.

SU-FF-T-247: Performance of Two Commercial MOSFET Systems at Low Doses in and Out of Field

Purpose: Some applications in clinical dosimetry require dose measurements in the 1–10 cGy range, such as in vivo dose verification measurements of critical structures that are near the field edge shielded by a jaw, block, or MLC leaf. Since such dose results from scatter, the spectrum is different than in the field. In IMRT, even infield measurements can be underneath an MLC leaf and therefore subject to a different spectrum for part of the irradiation. The goals of this study were to investigate 1) the repeatability and reproducibility of MOSFET measurements in the 1–10 cGy range; and 2) the impact of the different energy spectrum outside the beam on the dose response. Method and Materials: Dose measurements were performed on an 18 MV clinical linear accelerator using two commercial systems (Thomson Nielsen AutoSense and mobileMOSFET) both operated in high sensitivity mode. Measurements were made on the central axis and out‐of‐field along a profile extending perpendicularly from the center of a field edge. Absolute dose was measured with a calibrated Farmer chamber. Results: The AutoSense device was able to measure doses down to 5 cGy with a repeatability of 5.8% (all numbers refer to1 SD) using high sensitivity detectors. The mobileMOSFET device measured at 1 cGy with an average repeatability of 4.8 % for high sensitivity detectors and 7.7 % for standard detectors. Reproducibility was 3.8% and 4.2%, respectively. MOSFET response outside the field increased with increasing distance from the field edge generally up to 8 % at 4.8 cm. Reproducibility for this location was also about 8 %. Conclusions: The commercial MOSFET devices AutoSense and mobileMOSFET have been shown to reliably measure doses down to 5 cGy and 1 cGy, respectively. MOSFET response outside the beam is increased close to the measurement uncertainty.

Validation of Geospatial model for Biodiversity Characterization at Landscape Level—a study in Andaman & Nicobar Islands, India

The present paper deals with Biodiversity Characterization at Landscape Level, preparing thematic maps for spatial representation of landscape parameters and then validation of the geospatial model using a three-tier approach, viz., landscape analysis, field data extrapolation and geospatial analysis, for two groups of islands in Indian subcontinent. On-screen visual interpretation approach based on IRS LISS-III and Landsat TM data sets was used to delineate the vegetation communities. Field survey attributes on species diversity, economical/medicinal uses and endemism were suitably linked with satellite image-derived landscape attributes in a geospatial domain. The landscape parameters, viz., fragmentation and disturbance index, clearly indicate that Nicobar Islands are less disturbed compared to Andaman. The phytosociological data of different vegetation types collected from 544 stratified sample points was recorded with ground coordinates. The plant communities of Andaman show high plant diversity in terms of number of species (523 species) and more heterogeneity compared to those of Nicobar (347 species). Biological richness was estimated as a function of six biodiversity attributes (i.e., spatial, phytosociological, social, physical, economical and ecological) to stratify forest vegetation in two phytogeographically distinct groups of tropical islands, viz., Andaman and Nicobar, using a customized software, SPLAM. Validation of ecological indices had always been a major challenge for ecologist. Here, we discuss a validation technique using field-driven species regression equations for fragmentation (FR), disturbance (DI) and biological richness (BR) indices and propose improvements in the biological richness methodology. The research question of establishment of linkages between expressions of diversity at different scales is sought and thereby validating the existing model outputs has been proposed. The sensitivity of in-field measurements with landscape parameters has been explicitly analyzed. During validation, the species richness, diversity and mean basal area have shown slow decrease with sudden rise in intermediate levels followed by a steep decline at increasing levels of fragmentation and disturbance. The empirically derived regression coefficient has significant correspondence ( p < 0.05) in terms of community response in both island's groups. The vegetation communities in the forested landscape possess significant linkages with landscape scale processes, viz., FR and DI, as evident by the degree of correlation. The heterogeneity measured as diversity in habit group shows community dimensions in different spatial zones. The generation of baseline data on community ecology allows prioritization of planning process and evolves specific management practices. It may be concluded that the improved biodiversity assessment model and the designed validation techniques have enhanced the reliability of model thus widened the scope for its application in the rapid biodiversity assessment.

Construction and analytical applications of a palm-sized microcontroller-based amperometric analyzer

The design and development of a palm-sized (9cm×11cm×3cm), cost-effective, microcontroller-operated analyzer for direct amperometric measurements is described. The low-power-consumption electronics used allow 8h of autonomous operation with a 9V battery (110mAh), making thus this unit suitable for in-field measurements. Its operation is based mainly on the simple two-electrode potentiostatic mode, although the three-electrode mode is an option. The use of a microcontroller combined with analog and digital supporting circuits allows: (i) generation of the applied potential and the acquisition of analog signals with a gain auto-scaling capability; (ii) interaction with the operator for setting the measurement parameters; (iii) processing of data and displaying result on an LCD screen. Numerical data are automatically stored in memory and they can be retrieved by a personal computer through an RS232 port, either for creating measurements archives or for advanced processing. For this purpose, a program has been developed (on the LabVIEW platform) to provide a user-friendly graphical interface. The utility of this amperometric analyzer was assessed by performing experiments for the determination of ascorbic acid in standard solutions and pharmaceutical tablets.

Phase separation in Pr0.7Ca0.3MnO0.3: a case of weak quenched disorder

Phase separation (PS) in manganites has been suggested to arise as a consequence of quenched disorder due to the size mismatch of the A-site cations in the perovskite lattice. In this paper, we have used single crystal x-ray and in-field neutron diffraction measurements to investigate PS in Pr0.7Ca0.3MnO3, a compound with weak quenched disorder. Above the charge/ordering transition, our measurements show CE-type clusters with a coherence length of ∼20 Å. At TCE = 220 K the coherence length of the diffuse scattering diverges as a long-range ordered CE state is formed. Concurrently, the Huang scattering abruptly decreases at TCE as the diffuse CE-type reflections develop into Bragg reflections, suggesting that the transition to the CE-state is of the disorder–order type. Our neutron measurements of the ferromagnetic (FM) and antiferromagnetic (AF) ordering in Pr0.7Ca0.3MnO3, show the presence of FM 200 Å clusters coexisting with long range AF and FM phases. Application of field after zero-field-cooling leads to the reduction of the diffuse FM scattering. We argue that PS in this compound arises as a consequence of the Jahn–Teller strain from Mn3+ centres that act like quenched disorder.