Experimental Room Research Articles

Characterization of the H2O+CO2 continuum within the infrared transparency windows

Absorption spectra of humidified CO2 have been recorded at room temperature by cavity enhanced absorption techniques (CRDS and OFCEAS): (i) in three spectral ranges of the 1.6 µm window (5720–6045 cm−1; 6390–6460 cm−1 and 6570–6665 cm−1), (ii) in four narrow spectral intervals of the 2.3 µm window (4243–4255 cm−1; 4301.3–4302 cm−1; 4421.5–4440 cm−1 and 4518–4535 cm−1), and (iii) around 2853 cm−1. All these spectral ranges are situated in transparency windows of both H2O and CO2. The binary absorption coefficients (BCO2−H2O+BH2O−CO2)are retrieved from low pressure spectra (<1 atm) recorded with different molar fractions of water vapor in CO2 after subtracting the H2O and CO2 local monomer contributions and the self-continuum contribution of each species (i.e. H2OH2O and CO2CO2). Experimental room temperature binary coefficients are then compared to the only available empirical model based on line shape profiles with χ-factors. This model well reproduces our experimental values on the low- and high-frequency edges of the 1.6 µm window and gives a relatively good agreement for the 2853 cm−1 data point. Larger differences are observed in the 2.3 µm window where the calculated values are underestimated by a factor of 3. Around 6000 cm−1, an additional absorption peak is observed which is tentatively interpreted as a collision induced absorption band due to the simultaneous excitation of the H2O and CO2 molecules.

Performance on heating human body of an optimised radiant-convective combined personal electric heater

In this study, we developed an optimised radiant-convective combined personal electric heater, considering the limitations of traditional personal heaters that heat the human body through heat transfer of single convection or single radiation. Based on human participant experiments in simulated environments, the heating performance of the optimised personal heater on the human body was tested. The initial indoor air temperature in the experimental room was set to 14 °C. Twenty-four healthy young college students, including 12 males and females, were recruited as participants. They were required to experience three types of personal heaters in a sitting position: optimised combined personal heater (PHSR + C), convective personal heater (PHSC), and radiant personal heater (PHSR). During the 80-min-long experiment, their subjective ratings of thermal comfort, perceived air quality, sweating sensation, air movement sensation, and sick building syndrome were collected using questionnaires, and physiological parameters, such as skin temperature, tympanic temperature, and heart rate, were measured. The obtained results showed that, compared with PHSC and PHSR, PHSR + C increased the overall thermal sensation more rapidly (0.083 scale/min), and maintained the human body at a warmer condition. Moreover, when using PHSR + C, mean skin temperature and its change rate, and the thermal sensation vote of all local body parts were higher. The results indicate that the heating performance of this newly developed combined personal heater surpassed that of the two traditional types. Moreover, compared to using PHSC and PHSR, over 27% of the energy consumption was saved using PHSR + C.

Simulation Research on a Cogeneration System of Low-Concentration Photovoltaic/Thermal Coupled with Air-Source Heat Pump

In this paper, a low-concentration photovoltaic/thermal (LCPV/T) coupled with air-source heat pump (AHP) system is proposed which fully utilizes the heat generated by LCPV/T and improves the performance of the AHP. The system is built and investigated in the Transient System Simulation Program (TRNSYS) and an experimental room model is established to verify the feasibility of the system. The performance of the system is researched from the perspective of energy and exergy, and the system performance with LCPV/T and without LCPV/T is compared. Finally, the influence of the variation of key parameters of the system is studied. The results indicated that on the coldest day, the electrical efficiency of LCPV/T reached 10% which was equal to the electrical exergy efficiency. The maximum thermal efficiency was 31.88% while thermal exergy efficiency was 2.7%. The maximum coefficient of performance (COP) of AHP was 3.3, and the thermal exergy efficiency was 47%. The indoor temperature was maintained at about 20 °C in the heating season. When LCPV/T was adopted, the COP and thermal exergy efficiency of the AHP was generally higher than those without LCPV/T. In conclusion, the utilization of LCPV/T has a positive impact on the performance of the AHP.

The effect of air temperature, velocity and humidity on respiration rate and rectal temperature as an expression of heat stress in gestating sows.

Global warming combined with increased production (i.e. more piglets, more milk and consequently more heat) means that sows are more often challenged by heat stress. The objective was to develop an effective temperature (ET) equation to predict how air temperature, velocity and humidity affect the respiration rate (RR), rectal temperature (RT) and skin temperature (ST) as an expression of heat stress in gestating sows in order to elucidate the relationship between the thermal parameters and the sows' perception of the environment. The experimental room was equipped with a negative pressure ventilation system with diffuse air inlet through the ceiling, electrical heaters, steam generators and dehumidifiers. An air distribution unit was constructed to generate vertical air velocity. A total of 16 gestating sows were exposed to three temperatures (25°C, 29°C and 33°C), two levels of relative humidity (30% and 70%) and three levels of air velocity (0.2ms-1, 1ms-1 and 2.5ms-1). The RR, RT and ST were recorded every 30min throughout the three 2-h test periods. The estimated effects of humidity and velocity in relation to effect of temperature was nearly independent of whether it was determined from RR or RT, whereas the effect of humidity was much smaller when determined from ST. High coefficients of determination (>0.97) were found for the second order relationship between the estimated ET and RR, RT and ST. An increase in relative humidity from 50 to 70% corresponded to an increase in ET of 0.9°C, while an increase in air velocity from 0.2 to 1.0ms-1 corresponded to a decrease in ET of 1.2°C. The applied ET equation was useful for expressing the combined effect of temperature, humidity and velocity on animals exposed to heat stress. However, multiplying the effect of velocity by the temperature gradient between the animal and the surrounding air did not improve the estimation.

Using caloric efficiency to estimate the net energy value of expelled, extruded soybean meal relative to dehulled, solvent-extracted soybean meal and its effects on growth performance of nursery pigs.

This study aimed to estimate the net energy (NE) value of expelled, extruded soybean meal (MSBM) relative to dehulled, solvent-extracted soybean meal (SSBM) and determine its effects on growth performance of late nursery pigs. A total of 297 pigs (DNA 241 × 600) were weaned (BW 5.10 kg) and placed into 60 pens (2 rooms of 30 pens) with 5 pigs per pen balanced by gender and weaning weight. Pigs were fed a common diet for 21 d. Then, pens of pigs (BW 9.3 kg) were randomly assigned to one of five treatments to provide 12 replications per treatment. Treatments consisted of increasing amounts of MSBM replacing SSBM in the diet (0%, 25%, 50%, 75%, and 100%). All diets were fed for 28 d and were formulated to 1.30% standardized ileal digestible lysine and met or exceeded requirements for amino acids, calcium, and phosphorus. The SSBM diet was formulated to 2,421 kcal/kg and NE was not balanced between diets. Analyzed values for CP, EE, CF, and total lysine for the SSBM were 47.28%, 0.47%, 3.80%, and 3.00%, whereas the MSBM contained 47.41%, 6.88%, 5.32%, and 2.99%, respectively. The MSBM had increased values for KOH solubility and trypsin inhibitor (83.62% and 7,026 TIU/g) compared to the SSBM (73.05% and 3,011 TIU/g), whereas urease activity was similar between the two (0.03 and 0.02 Δ pH, respectively). Data were analyzed using Proc GLIMMIX (SAS 9.4; Cary, NC) with pen as the experimental unit and room as the blocking factor. There was no evidence of differences in ADG and ADFI in pigs fed diets with increasing concentrations of MSBM. Pigs fed diets with increasing concentrations of MSBM had improved (linear, P < 0.001) G:F and caloric efficiency on an NE basis. Using caloric efficiency to estimate NE of the MSBM relative to SSBM, MSBM was estimated to have a value of 2,566 kcal/kg. In conclusion, MSBM contains approximately 123% of the energy of SSBM, which improved feed efficiency when fed to nursery pigs.

Ab Initio Calculation of Accurate Electronic and Transport Properties of Zinc Blende Gallium Antimonide (zb-GaSb)

This article reports the results of our investigations on electronic and transport properties of zinc blende gallium antimonide (zb-GaSb). Our ab-initio, self-consistent and non-relativistic calculations used a local density approximation potential (LDA) and the linear combination of atomic orbital formalism (LCAO). We have succeeded in performing a generalized minimization of the energy, using the Bagayoko, Zhao and Williams (BZW) method, to reach the ground state of the material while avoiding over-complete basis sets. Consequently, our results have the full physical content of density functional theory (DFT) and agree with available, corresponding experimental data. Using an experimental room temperature lattice constant of 6.09593?, we obtained a direct band gap of 0.751 eV, in good agreement with room temperature measurements. Our results reproduced the experimental locations of the peaks in the total density of valence states as well as the measured electron and hole effective masses. Hence, this work points to the capability of ab-initio DFT calculations to inform and to guide the design and the fabrication of semiconductor based devices—provided a generalized minimization of the energy is performed.

Arduino-Based Design and Implementation of Experimental Rooms with a Trombe Wall for Solar Cells Applications

Arduino-Based Design and Implementation of Experimental Rooms with a Trombe Wall for Solar Cells Applications

Experimental study on a modular thermo-activated building system for improving indoor thermal environment and energy saving

Thermo-activated Building Systems is an energy-efficient envelope insulation technology. In this paper, the Modular Thermo-activated Building Systems (MTABS) is proposed to enable flexible installation and maintenance of embedded pipe. Two scaled-down experimental rooms of the same size were built, in which the normal energy-saving wall (NW) and the MTABS wall were applied to the south-facing wall respectively. The MTABS for impacting on the indoor thermal environment and energy saving were measured in continuous low-grade heat injection mode under winter outdoor conditions in Hefei, and were analyzed in comparison with the NW. Experimental results show that MTABS can effectively improve the indoor thermal environment. The average temperature difference between indoor and outdoor of MTABS is 6.72 °C higher than that of NW; when the heat source temperature is 25 °C, the cumulative daily heat fluxes of MTABS is 44.0 kWh·m-2, which providing auxiliary indoor heating while significantly reduces energy consumption.

Interventional Effect of Nanosilver Paint on Fungal Load of Indoor Air in a Hospital Ward.

Hospital ward environments contain various types of microorganisms, in which fungal agents are one of the main contaminants that may cause hospital-acquired infections. Regarding this, the aim of the present study was to evaluate the effect of nanosilver paint on reducing fungal contaminants of indoor air in an educational, research, and treatment center. Two rooms in the hematology ward were selected. One room was painted using usual paint (control room) and the other room was painted with paint containing nanosilver particles (experimental room). One hundred and twelve samples were collected using active (Anderson BioSampler) and passive (settle plate or open plate) air sampling techniques. The samples were incubated for 3–7 days at 35°C, and the positive fungal cultures were examined according to morphological and microscopic characteristics. Following active sampling, the mean and standard deviation of the number of colony-forming units (CFU/m3) of fungi colonies in the experimental and control rooms were 29.21 ± 17.99 and 22.50 ± 10.02 before intervention and 13.79 ± 6.20 and 31.07 ± 21.1 after intervention, respectively. Following passive sampling, the number of CFU/plate in the experimental and control rooms was 6 and 0 before and 1and 1 after intervention, respectively. The use of the nanosilver paint was effective in reducing air fungal contamination. Moreover, the active sampling method was more sensitive to measuring the concentration changes for fungal bioaerosols.

Экспериментальные исследования истечения пропана в закрытом производственном помещении

В статье представлены результаты экспериментальных исследований истечения пропана в различных направлениях в закрытом помещении. Рассматривался случай, когда источник истечения находился в багажнике автомобиля - имитация нахождения автомобиля с газомоторным топливом на станции технического обслуживания. Целью эксперимента являлось изучение механизма пространственного распространения газа в закрытом помещении для валидации математических моделей, используемых в программном комплексе ANSYS Fluent при моделировании поступления пропана в закрытое помещение. This scientific work describes a test conducted in a multidisciplinary test box on the testing training ground of the Orenburg branch of the All-Russian Research Institute for Fire Protection of EMERCOM of Russia. For the experiment there was built a room to simulate a service station (or parking box) for two cars. The frame was made of wooden bars and a plastic film was used to isolate the internal volume. The experimental installation consisted of a gas source with an internal diameter of 5 mm, located in the center of the room, and a system for gas supply and registration of experimental data from six gas analyzers SGOES-2 with a measurement range of pre-explosive concentrations from 0 to 100% of the lower concentration limit of flame propagation (NKPR) or a volume fraction from 0 to 1.7% with absolute ± 5% NKPR (in the range from 0 to 50% NKPR) and relative ± 10% NKPR (in the range from 50 to 100% NKPR) errors. In the center of the experimental room there was placed a car with the gas source in the trunk. All openings to the interior were insulated with plastic film and mounting foam. Natural cracks were left between the trunk lid and the body. The gas source is located in the trunk of the car and is directed towards the wide part of the trunk at an angle of 30 degrees relative to the floor (simulating the location of the gas cylinder used in cars). The gas analyzers were located along the wall, where the outflow is directed along the perimeter of the trunk, and one gas analyzer was located directly in the trunk behind the gas analyzer to control gas contamination. Propane has been released into the trunk with a constant flow rate of 2.8 m/h for 5 minutes. There were 8 test starts of the gas supply system (the flow vertically down), and then there were carried out 3 experiments per 3 series of tests in each. The purpose of the test was to study the mechanism of spatial gas propagation in an confined space for validation of mathematical models used in the ANSYS Fluent software package when modeling the propane intake into the confined space

Numerical Model Development of the Air Temperature Variation in a Room Set on Fire for Different Ventilation Scenarios

Statistics show that most fires occur in civil residential buildings. Most casualties are due to the inhalation of hot air loaded with smoke, leading to intoxication with substances harmful to the human body. This research aimed to develop a CFD model that relates the operation of the sprinkler system to the operation of the ventilation system through the air temperature in a specific point close to the sprinkler position. A real-scale experiment was carried out, and a CDF model was developed. Several parameters of the CFD model (thermal conductivity of the experimental test room walls, numerical grid elements’ dimensions, burner heat release rate variation) were imposed to the model, so that the resulting entire time variation of the temperature next to the sprinkler location corresponds to the real measured variation. Two other experiments were used to validate the numerical model. Besides the air temperature, at this point, other essential parameters were determined in the entire experimental space: indoor air temperature, visibility, oxygen concentration, and carbon dioxide concentration. We found that if the ventilation rate increases, the indoor temperatures in that specific point decrease, and the sprinkler is activated later or, in some cases, it might never be activated. However, this conclusion is not valid for the entire analyzed space, as the ventilation system alongside the natural air movement imposes specific air speed and specific temperature distribution inside the analyzed space.

Five Different Noise Intensities Robustly Affects Corticosterone, Gastrin and Endothelin-1 Responses and Initiated Gastric Tissue Damage in Wistar Rats

Likewise other stress response noise stress is also affects the homeostasis of the biological systems and produce stress response in the form of Corticosterone to prevent the damage but if the exposure is longer with higher magnitude it may disrupt the robust ability of the homeostasis and could produce the damage to the biological systems. The goal of our study was to see how five different noise intensities affected stomach tissue damage. 42 healthy rats were divided into five different stress exposure group, normal control (NC) and sham control (SC) groups. Noise stress exposure was delivered for 1 hour per day continued for 30 days in all five noise exposed groups by specially designed noise chamber whereas sham control group of animals kept in noise chamber for 1 hour per day continued for 30 days without noise stress exposure and control group of animals neither exposed to noise stress of any intensities and nor kept in noise chamber without noise but remain in the same experimental room in their homecage for 30 days respectively. Results of the study showed that animals exposed to 60 and 80 dB noise give habituated and not significant Corticosterone, Gastrin and Endothelin-1 responses compared to NC and SC groups while animals exposed to 100, 120 and 140 dB had significantly higher Corticosterone, Gastrin and Endothelin-1 response and also chronic gastric damage was observed compared to later two noise exposed groups respectively. Study concluded that not only higher but also lower noise intensities also initiated the gastric damage even after the adaptation.

A Medium-Sized Monitor Loudspeaker for Multichannel Audio Environments Conforming to ITU-R Recommendation

A medium-sized monitor loudspeaker is proposed and developed for multichannel audio environments conforming to the requirements of International Telecommunication Union Radiocommunication Sector (ITU-R): Recommendation (Rec.) ITU-R BS.1116-3. Moderate monitor loudspeakers are currently required in dubbing studios and experimental rooms in which multiple loudspeakers need to be installed. Such a loudspeaker requires a sufficient maximum sound pressure level, a flat frequency response, and an appropriate directivity providing a practical coverage; a size acceptable for multichannel audio environments is also essential. The proposed loudspeaker is developed realizing the directivity index within the specified target range by combining multiple loudspeaker units and controlling the cross-over frequencies. An integrally powered structure is adopted for convenience of installation, and a switching amplifier is selected for downsizing. As a result, the size of the developed loudspeaker gets suitable for the existing multichannel audio environments. The acoustic characteristics of the developed loudspeaker is investigated both in static and dynamic conditions. The measurement results verify that the developed loudspeaker conforms to almost all specifications of Rec. ITU-R BS.1116-3.

Multi-session Analysis of Movement Variability While Reaching in a Virtual Environment.

The acquisition of neurophysiological data during awake, behaving animal experiments typically involves experimental sessions lasting several days to weeks. Therefore, it is important to understand natural fluctuations in behavioral performance over such periods. Here we quantified patterns of movement variability for reaches performed by two monkeys across five daily experimental sessions. The monkeys were trained to move in an immersive virtual reality (VR) environment that was designed to resemble the experimental room. Visual feedback of the limb was provided using VR avatar arms that were controlled through a reflective marker-based motion capture system. Additionally, tactile cues were provided in the form of physical reach targets. Spatial variability was characterized at early (peak acceleration) and late (movement endpoint) kinematic landmarks. We found that the magnitude of variability was generally larger at peak acceleration than at the endpoint but was relatively consistent across days and within animals. The spatial characteristics of variability were also generally highly consistent at peak acceleration both within and between animals but were noticeably less so at the endpoint. The results highlight the benefits of using early kinematic landmarks such as peak acceleration for quantifying movement variability in reaching studies involving animals.

Subjective assessment of thermal comfort by radiant cooling in a tropical hot humid climate

This paper investigated thermal comfort of radiant cooling with subjects who are accustomed to a tropical hot humid climate. Thermal sensation, thermal acceptability, and thermal preference were assessed from observations of a large group of the subjects in a radiant cooling experimental room refurbished as an office-like environment. The analysis results showed that the operative temperature for the thermal neutrality was about 25.0 °C, and the acceptable temperature ranged from 22.5 °C to 26.5 °C. Air movement played a key factor influencing on the subject preference in the radiant cooling, while the room relative humidity had less significance. In this study, a field comfort survey of the conventional mixed-air system was also carried out in real occupied spaces by using the same questionnaire and measuring devices from the radiant comfort experiments. The comparison showed that the thermal responses of the subjects were different between the two air-conditioning systems.

The FragmentatiOn Of Target (FOOT) Experiment and Its DAQ System

The FragmentatiOn mymargin Of Target (FOOT) experiment aims to provide precise nuclear cross section measurements for two different fields: hadrontherapy and radio-protection in space. The main reason is the important role the nuclear fragmentation process plays in both fields, where the health risks caused by radiation are very similar and mainly attributable to the fragmentation process. The FOOT experiment has been developed in such a way that the experimental setup is easily movable and fits the space limitations of the experimental and treatment rooms available in hadrontherapy treatment centers, where most of the data takings are carried out. The trigger and data acquisition system needs to follow the same criteria and it should work in different laboratories and different conditions. It has been designed to acquire high statistics samples to fulfill the accuracy requirements of the physics analysis. Data-taking is being monitored online to allow the shift crew to verify the correct functioning of the system.

Radiant catalytic ionization improves the microbiological status of rodent facilities without affecting the prooxidative status of mice.

The main microbial contaminants of rooms in which laboratory rodents are housed are bacteria and fungi. Restriction of microbial growth to below threshold levels requires the application of various sophisticated antimicrobial techniques that must be effective and safe for the animals. Some of the most commonly used techniques, including chemical disinfection, ventilation, filtration, sterilization and radiation, are not always sufficiently effective. The aim of the current study was to evaluate the efficacy of a modern technique (i.e. radiant catalytic ionization (RCI)) on the microbiological status of an animal care facility, and the health of the mice housed therein. The experiment, conducted over seven days, compared an experimental room with an RCI system permanently turned on with a negative control room. At the completion of the experiment, the number of bacteria in the RCI room air and on its walls was lower than that in the control room (p < 0.01 in both cases). Values of the basic prooxidative parameter, thiobarbituric acid reactive substances concentration, in tissues of mice from the RCI room were within allowed boundaries. Hence, application of an RCI system proved to be an ideal technique to ensure high hygienic standards in animal rooms without any adverse effects on the animals housed therein.

Encounters in and with Summer Camps—Happy Childhood, Alternative Bildung, or What?

Although they commonly are associated with recreation, summer camps for children can be seen as educational arenas that both supplement and challenge school education. Summer camps provide education in a broad sense of bildung. The article aims at describing what is experienced in summer camps and proposes various theoretical frames for these bildung processes. The main focus is on summer camps in Russia, and we interviewed Russian informants who participated in summer camps. The findings were that learning in the camps tends to be non-instrumental, allowing room for play and experimentation for both pupils and teachers. Social learning is marked by collective elements such as camp rituals and spontaneous solidarity, both forming an individual personality. Outdoor activities are important because they connect children to nature and develop a sense of place marked by biophilia. Furthermore, nature’s materiality creates a sense of being in the world, which means developing a sense of multiple relational settings, spanning from the materialities of geography, place, and objects to experiencing new social settings in the form of solidarity, ritual, and friendship.

Investigation of the stray neutron fields produced from proton irradiated Ta, Co-59, Ni, Fe, Inconel X750 and stainless steel 310 targets in a materials testing laboratory environment

A nested neutron spectrometer was used to measure the stray neutron fluence and ambient dose equivalent produced by protons from a 4 MV tandem accelerator on various target materials at the Reactor Materials Testing Laboratory (RMTL), Queen's University, Kingston, Ontario. The nested neutron spectrometer utilizes a Helium-3 proportional counter and measures the thermal neutron count rate as a function of moderator shell-thickness. Using custom unfolding software, neutron spectra and neutron dosimetric quantities were derived at various locations within the RMTL. The nested neutron spectrometer can be operated in both a pulse mode and current mode allowing for measurements over a wide range of accelerator beam currents. All measurements conducted at the facility were within the main accelerator chamber and experimental target rooms. Target room measurements were conducted with a variety of target materials representative of those to be used for research planned at the RMTL.

The Performance of LiF:Mg-Ti for Proton Dosimetry within the Framework of the MoVe IT Project

Proton therapy represents a technologically advanced method for delivery of radiation treatments to tumors. The determination of the biological effectiveness is one of the objectives of the MoVe IT (Modeling and Verification for Ion Beam Treatment Planning) project of the National Institute for Nuclear Physics (INFN) CSN5. The aim of the present work, which is part of the project, was to evaluate the performance of the thermoluminescent dosimeters (TLDs-100) for dose verification in the proton beam line. Four irradiation experiments were performed in the experimental room at the Trento Proton Therapy Center, where a 150 MeV monoenergetic proton beam is available. A total of 80 TLDs were used. The TLDs were arranged in one or two rows and accommodated in a specially designed water-equivalent phantom. In the experimental setup, the beam enters orthogonally to the dosimeters and is distributed along the proton beam profile, while the irradiation delivers doses of 0.8 Gy or 1.5 Gy in the Bragg peak. For each irradiation stage, the depth–dose curve was determined by the TLD readings. The results showed the good performance of the TLDs-100, proving their reliability for dose recordings in future radiobiological experiments planned within the MoVe IT context.