Defining the effects of ambient conditions in large-scale fire tests

2010 ◽  
Vol 34 (3) ◽  
pp. 404-411 ◽  
Author(s):  
Francesco Tamanini
Keyword(s):  
Large Scale ◽  
Fire Tests ◽  
Ambient Conditions

scholarly journals Rapid synchronized fabrication of vascularized thermosets and composites

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Mayank Garg ◽  
Jia En Aw ◽  
Xiang Zhang ◽  
Polette J. Centellas ◽  
Leon M. Dean ◽  
...  
Keyword(s):  
Large Scale ◽  
Capillary Flow ◽  
External Heat ◽  
Frontal Polymerization ◽  
Self Healing ◽  
Vascular Networks ◽  
Ambient Conditions ◽  
External Energy ◽  
Imaging Phantoms ◽  
Vascular Structures

AbstractBioinspired vascular networks transport heat and mass in hydrogels, microfluidic devices, self-healing and self-cooling structures, filters, and flow batteries. Lengthy, multistep fabrication processes involving solvents, external heat, and vacuum hinder large-scale application of vascular networks in structural materials. Here, we report the rapid (seconds to minutes), scalable, and synchronized fabrication of vascular thermosets and fiber-reinforced composites under ambient conditions. The exothermic frontal polymerization (FP) of a liquid or gelled resin facilitates coordinated depolymerization of an embedded sacrificial template to create host structures with high-fidelity interconnected microchannels. The chemical energy released during matrix polymerization eliminates the need for a sustained external heat source and greatly reduces external energy consumption for processing. Programming the rate of depolymerization of the sacrificial thermoplastic to match the kinetics of FP has the potential to significantly expedite the fabrication of vascular structures with extended lifetimes, microreactors, and imaging phantoms for understanding capillary flow in biological systems.

scholarly journals Large-scale Facade Fire Tests Conducted Based on ISO 13785-2 with Noncombustible Facade Specimens

2011 ◽  
Vol 31 (1) ◽  
pp. 1-22 ◽  
Author(s):  
Hideki Yoshioka ◽  
Yoshifumi Ohmiya ◽  
Masaki Noaki ◽  
Masashi Yoshida
Keyword(s):  
Large Scale ◽  
Fire Tests

scholarly journals Influence of Porcine Housing Density on Species Diversity and Number of Airborne Microorganisms at Fattening Facilities

2006 ◽  
Vol 75 (4) ◽  
pp. 533-540 ◽  
Author(s):  
Ž. Pavičić ◽  
T. Balenović ◽  
H. Valpotić ◽  
A. Tofant ◽  
M. Popović ◽  
...  
Keyword(s):  
Species Diversity ◽  
Large Scale ◽  
Coliform Bacteria ◽  
Winter Period ◽  
Ambient Conditions ◽  
Airborne Microorganisms ◽  
Housing Density ◽  
Gram Positive Bacteria ◽  
Microclimatic Conditions ◽  
Bacteria And Fungi

Microbiological composition of air, as a factor of ambient conditions in animal facilities can significantly influence performance, health and animal welfare in the swine production. The aim of this investigation was to determine, by monitoring primary microclimatic conditions, the possible association of the number of fattening pigs per unit of housing space with species diversity and number of airborne microorganisms. The research was conducted at a fattening and finishing facility of 450 m2 (equipped with 44 pens designed for 10 animals each) with low-pressure ventilation in three different trials. The first trial was conducted during the autumn-winter period with the capacity of 440 animals (0.7 m2 of pen area per fattening pig), the second trial was conducted during the winter-spring period with 356 animals (0.8 m2 of pen area per fattening pig), and the third trial was conducted during the spring-summer period with 312 animals (1.0 m2 of pen area per fattening pig). The air samples for isolation of fungi and mesophilic, haemolytic, and coliform bacteria were taken and microclimatic conditions were monitored during each trial at the same consecutive weekly periods. According to the data obtained from all trials, the total number of bacteria and fungi did not exceed 104 and 103 CFU per m3, respectively. The most numerous were gram-positive bacteria, followed by gram-negative bacteria and fungi. The total number of airborne microorganisms correlates significantly (at p < 0.05) with porcine housing density. These data may be useful for the assessment of housing density at fattening facilities that will not compromise swine health and welfare regarding the microbiological air quality, and thus may contribute to the implementation of optimal rearing conditions in large-scale animal producing units.

scholarly journals Analysis of the Spatial and Temporal Distribution of Process Gases within Municipal Biowaste Compost

2019 ◽  
Vol 11 (8) ◽  
pp. 2340 ◽  
Author(s):  
Stegenta ◽  
Sobieraj ◽  
Pilarski ◽  
Koziel ◽  
Białowiec
Keyword(s):  
Cross Sections ◽  
Large Scale ◽  
Temporal Distribution ◽  
Municipal Sewage ◽  
Municipal Sewage Sludge ◽  
O2 Evolution ◽  
Spatial And Temporal Distribution ◽  
Ambient Conditions ◽  
Process Gas ◽  
Process Gases

Composting processes reduce the weight and volume of biowaste and produce products that can be used in agriculture (e.g., as fertilizer). Despite the benefits of composting, there are also problems such as odors and the emission of pollutants into the atmosphere. This research aimed to investigate the phenomenon of process gas (CO, CO2, NO, O2) evolution within a large-scale municipal composter. The effects of turning frequency and pile location (outdoor vs. indoors) on process gas and temperature spatial and temporal evolution were studied in six piles (37‒81 tons of initial weight) over a six-month period. The biowaste consisted of green waste and municipal sewage sludge. The chemical composition and temperature of process gases within four cross sections with seven sampling locations were analyzed weekly for ~7–8 weeks (a total of 1375 cross sections). The aeration degree, temperature, CO, CO2, and NO concentration and their spatial and temporal distribution were analyzed. Final weight varied from 66% reduction to 7% weight gain. Only 8.2% of locations developed the desired chimney effect (utilizing natural buoyancy to facilitate passive aeration). Only 31.1% of locations reached thermophilic conditions (necessary to inactivate pathogens). Lower O2 levels corresponded with elevated CO2 concentrations. CO production increased in the initial composting phase. Winter piles were characterized by the lowest CO content. The most varied was the NO distribution in all conditions. The O2 concentration was lowest in the central part of the pile, and aeration conditions were good regardless of the technological regime used. Turning once a week was sufficient overall. Based on the results, the most favorable recommended procedure is turning twice a week for the first two weeks, followed by weekly turning for the next two weeks. After that, turning can be stopped unless additional removal of moisture is needed. In this case, weekly turning should continue until the process is completed. The size of the pile should follow the surface-to-volume ratio: <2.5 and <2 for cooler ambient conditions.

scholarly journals Enhanced Agronomic Efficiency Using a New Controlled-Released, Polymeric-Coated Nitrogen Fertilizer in Rice

Plants ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1183
Author(s):  
Ricardo Gil-Ortiz ◽  
Miguel Ángel Naranjo ◽  
Antonio Ruiz-Navarro ◽  
Sergio Atares ◽  
Carlos García ◽  
...  
Keyword(s):  
Controlled Release ◽  
Large Scale ◽  
Slow Release ◽  
Growth Parameters ◽  
Crop Management ◽  
Ambient Conditions ◽  
N Losses ◽  
Controlled Release Fertilizer ◽  
Large Scale Field ◽  
Use Efficiency

Fertilizer-use efficiency is one of the most critical concerns in rice cultivation to reduce N losses, increase yields, and improve crop management. The effects of a new polymeric-coated controlled-release fertilizer (CRF) were compared to those of other slow-release and traditional fertilizers in a microscale experiment, which was carried out in cuvettes under partly controlled ambient conditions, and a large-scale field experiment. To evaluate the fertilizer’s efficiency, nitrogen and water-use efficiency were calculated using the measurement of different photosynthetic and crop yield parameters. Improved responses regarding some of the analyzed physiological and growth parameters were observed for those plants fertilized with the new CRF. In the microscale experiment, significantly increased yields (ca. 35%) were produced in the plants treated with CRF as compared to traditional fertilizer. These results were in accordance with ca. 24% significant increased levels of N in leaves of CRF-treated plants, besides increased P, Fe, Mn, and cytokinin contents. At the field scale, similar yields were obtained with the slow-release or traditional fertilizers and CRF at a 20% reduced N dose. The new controlled-release fertilizer is a urea-based fertilizer coated with lignosulfonates, which is cheaply produced from the waste of pulp and wood industries, containing humic acids as biostimulants. In conclusion, CRF is recommended to facilitate rice crop management and to reduce contamination, as it can be formulated with lower N doses and because it is ecological manufacturing.

scholarly journals Recent Advancements in Crystalline Pb-Free Halide Double Perovskites

Crystals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 62 ◽  
Author(s):  
Muhammad Usman ◽  
Qingfeng Yan
Keyword(s):  
Large Scale ◽  
Optoelectronic Properties ◽  
Double Perovskites ◽  
Ambient Conditions ◽  
Photoelectric Properties ◽  
Potential Alternative ◽  
High Carrier Mobility ◽  
Halide Perovskites ◽  
Synthesis Composition ◽  
Lead Halide

Lead halide perovskites have gained more and more attention because of their ease of synthesis and excellent photoelectric properties including a large absorption coefficient, long carrier lifetime, long carrier diffusion length, and high carrier mobility. However, their toxicity, instability, and phase degradation in ambient environments impede their large-scale applications. To address these concerns, it is desirable to find stable alternative halide perovskites without toxicity and with comparable optoelectronic properties to lead-based perovskites. Over the years, a considerable number of lead-free halide perovskites have been added to this family of materials, including A2B’B’’X6, A2BX6, and A3B2X9 type perovskites. Among these, double perovskites with the general formula A2B’B’’X6 are deemed to be a potential alternative to lead halide perovskites as they possess good stability under ambient conditions and excellent optoelectronic properties. In this review, recent progress in exploring Pb-free halide double perovskites is highlighted. The synthesis, composition-tuning, physical properties, and applications of representative 3D, 2D, and nanocrystal A2B’B’’X6 double perovskites are introduced. In addition, perspectives about current challenges and solutions in this field are also provided.

scholarly journals Efficient CdTe Nanocrystal/TiO2 Hetero-Junction Solar Cells with Open Circuit Voltage Breaking 0.8 V by Incorporating A Thin Layer of CdS Nanocrystal

Nanomaterials ◽  
2018 ◽  
Vol 8 (8) ◽  
pp. 614 ◽  
Author(s):  
Xianglin Mei ◽  
Bin Wu ◽  
Xiuzhen Guo ◽  
Xiaolin Liu ◽  
Zhitao Rong ◽  
...  
Keyword(s):  
Solar Cells ◽  
Thin Layer ◽  
Large Scale ◽  
Open Circuit Voltage ◽  
Open Circuit ◽  
Band Alignment ◽  
Ambient Conditions ◽  
Solution Processed ◽  
Processing Technologies ◽  
Cdte Nanocrystal

Nanocrystal solar cells (NCs) allow for large scale solution processing under ambient conditions, permitting a promising approach for low-cost photovoltaic products. Although an up to 10% power conversion efficiency (PCE) has been realized with the development of device fabrication technologies, the open circuit voltage (Voc) of CdTe NC solar cells has stagnated below 0.7 V, which is significantly lower than most CdTe thin film solar cells fabricated by vacuum technology (around 0.8 V~0.9 V). To further improve the NC solar cells’ performance, an enhancement in the Voc towards 0.8–1.0 V is urgently required. Given the unique processing technologies and physical properties in CdTe NC, the design of an optimized band alignment and improved junction quality are important issues to obtain efficient solar cells coupled with high Voc. In this work, an efficient method was developed to improve the performance and Voc of solution-processed CdTe nanocrystal/TiO2 hetero-junction solar cells. A thin layer of solution-processed CdS NC film (~5 nm) as introduced into CdTe NC/TiO2 to construct hetero-junction solar cells with an optimized band alignment and p-n junction quality, which resulted in a low dark current density and reduced carrier recombination. As a result, devices with improved performance (5.16% compared to 2.63% for the control device) and a Voc as high as 0.83 V were obtained; this Voc value is a record for a solution-processed CdTe NC solar cell.

Impact of Water on the Fatigue Performance of Large-Scale Grouted Connection Tests

2016 ◽  
Author(s):  
Peter Schaumann ◽  
Alexander Raba ◽  
Anne Bechtel
Keyword(s):  
Large Scale ◽  
Fatigue Tests ◽  
Fatigue Performance ◽  
Small Scale ◽  
Test Results ◽  
Ambient Conditions ◽  
Research Project ◽  
Joint Research Project ◽  
Scale Test ◽  
The Impact

Grouted connections represent a common joining technique between substructure and foundation piles of offshore oil & gas platforms as well as of offshore wind turbines. Due to cyclic loads arising from wind and wave actions the fatigue performance of the connection has to be considered. In lattice substructures like jackets the grouted connections are located at seabed level being fully submerged during their entire lifetime. Today’s fatigue design regulations are based on investigations neglecting any influence of the surrounding water since they were conducted in dry ambient conditions. So far, only Germanischer Lloyd gives additional recommendations for submerged grouted connections. At the Institute for Steel Construction, Leibniz Universität Hannover, Germany investigations of the joint research project ‘GROWup’ focus on the fatigue performance of axially loaded grouted connections. The project is funded by the Federal Ministry for Economic Affairs and Energy (BMWi, funding sign: 0325290) and is the third project in a row dealing with grouted connections. As part of this research project, cyclic loading tests on small-scale and large-scale grouted connections with shear keys are conducted. Small-scale fatigue tests showed a reduced number of endurable load cycles for connections when tested in wet ambient conditions. However, the transferability of these findings to a larger scale was still doubtful due to unknown scale effects. Therefore, the impact of water on the fatigue performance was tested recently at large-scale grouted connections. Previous to the submerged large-scale grouted connection fatigue tests, similar test specimens were exposed to alternating loads at dry ambient conditions. Comparison of both large-scale test results under wet and dry conditions enable to estimate the influence of water on the fatigue performance of grouted connections. Reflection of the small-scale test results gives hints on the scale effect. Test preparation, test results and design recommendations are presented in the paper.

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