Double Glass Research Articles

Dynamic breakage of double glass spheres chain subjected to impacting loading

Strain energy releasing due to local failure plays an important role in the dynamic breakage of the brittle medium. A series of experiments are conducted based on the Split Hopkinson pressure bar (SHPB) device. Two contact modes, i.e. the rigid contact between two spheres and the elastic contact between the sphere and the impact/support bar, are introduced by using the double sphere chain sample. Two methods, e.g. the Infrared temperature measurement (ITMS) method and the Digital image correlation (DIC) method, are utilized to trace the fracture sequence of the chain samples under impact velocity 5.0–13.0 m/s. The effects of strain energy releasing to the force-displacement curves, the temperature rising process, and the broken products of the chain samples are demonstrated in detail. Releasing of strain energy causes a delayed recompression process, and the delayed time decreases with increasing of impact velocity, which was caused by the formation and releasing of local strain in elastic contact mode. The approaches to evaluate the effects of strain energy releasing are then proposed to analyze the force-displacement curves and the temperature rising process. The elevated temperature is estimated to be a linear relationship to ε˙2/3. It is of great significance for the profound understanding of the failure mechanism of sphere aggregates.

Comparative Analysis of Occupant Thermal Comfort, Energy Consumption, and CO2 Emissions for an Educational Building in Cold Climate: A Case Study in Canada

Global climate change and global warming capture the attention of planners seeking more sustainable buildings to reduce dependence on fossil fuels and minimize energy consumption. Consequently, architects have developed buildings over the years and applied more sustainable strategies to cope with the environment, either in the shape of the building, the design of openings, or the use of more sustainable materials. These strategies provide more thermal comfort for long-term users. As a result, it is necessary to know the exact effect of using these strategies on thermal performance and energy consumption inside buildings. Therefore, researchers have developed many energy simulation tools and programs to provide a clear view of the nature of the building’s thermal performance and energy consumption based on data inputs about local weather situations of the building. Thus, we must know the ability of the software to model different design strategies and be sure that the results are valid. This paper aims to make an environmental simulation of an educational building in Montreal, Canada, using Design-Builder simulation and compare it with the as-built equivalent thermal zones applying different glazing materials, which is the main element of the building facade to enhance the thermal comfort with the lowest energy consumption and CO2 emissions. This paper shows that using double glass low E 6/6mm Air gap is better for the case study building in cold climate weather that increases thermal comfort for the users, reduces energy consumption by 18.63%, and also reduces CO2 emissions by 18.57% per year.

Chipping Away at the Glass Ceiling: A Social Psychological Perspective on the Role of Women Directors

The glass ceiling in corporate boards all over the world has sparked debate in research and practice. Advocates of chipping away at this glass ceiling argue the importance of gender diversity to improve board monitoring and eventually firm outcomes, while others dispute the benefits of increasing women on boards. In this study, we draw on the social psychological perspective to analyze whether increasing the proportion of women on the boards of publicly listed Spanish firms is relevant for corporate governance. Our findings show that the presence and leadership positions of women on the board and/or the nomination committee are not significantly associated with the increase in incorporating new women directors. Moreover, we find that women are less likely than men to be assigned with leadership positions, both in the board as a whole or its board committees. These findings suggest that women face gender bias, resulting in a double glass ceiling in corporate boards. Furthermore, the presence of women directors—even when assigned with leadership positions in the board or relevant board committees—does not improve or diminish the main board monitoring activities, thus uncovering that women on boards may yield similar outcomes despite being outnumbered by men in the boardroom.

Double glassy states and large spontaneous and conventional exchange bias in La1.5Ca0.5CoFeO6 ferrimagnetic double perovskite

The structural and magnetic properties of hole doped double perovskite La1.5Ca0.5CoFeO6 have been investigated by measuring x-ray photoemission spectroscopy, neutron powder diffraction and magnetization. A ferrimagnetic transition is observed at T C∼ 167 K. The presence of anti-site disorder (ASD) in La1.5Ca0.5CoFeO6 has also been demonstrated. Double re-entrant cluster glass transitions (T 1∼ 11 K and TS ∼ 35 K) were observed which has been attributed to the ASD effect. The presence of both large spontaneous exchange bias H SEB ∼ 2.106 kOe and giant conventional exchange bias H CEB ∼ 1.56 T at 5 K has also been observed which can be attributed to the coexistence of long range magnetic ordering and glassy state. The experimental observations were explained with the results obtained by the density functional theory calculation. The presence of double glassy states, large exchange-bias effect and different magnetic phases make this system a potential candidate for spintronic applications.

Influence of Gelatin-Based Coatings Crosslinked with Phenolic Acids on PLA Film Barrier Properties

Single-use plastics are a major source of pollution and biodegradable polymers could be the best substitute, as they possess similar barrier and functional properties. Aiming at improving barrier properties and providing antioxidant bioactivity, PLA (PolyLactic Acid) films were coated with a crosslinked suspension of plasticized gelatin incorporating phenolic compounds. The coating process induced weak modifications of PLA properties due to plasticization by moisture and glycerol from the coating suspension. Indeed, a double glass transition was displayed. The water vapor barrier properties of the PLA-coated films were not significantly affected. Phenolic compounds induced a crosslinking of the gelatin network, slightly decreasing the moisture sensitivity and surface hydrophilicity. Therefore, the mechanical properties of PLA were maintained after coating and their barrier properties were highly improved, with up to a 600-fold reduction of the oxygen transfer rate. These results make possible new applications for oxidation-sensitive foods, and even for semi-moist foods.

Experimental Investigation of Integrated Energy Storage on Thermal Performance Enhancement of Evacuated Glass-Thermal Absorber Tube Collector (EGATC) for Air Heating Application

Thermal energy storage (TES) in solar thermal application assist to increase the performance and efficiency of the solar thermal collector system. Various technique has been developed to enhance TES performance such as using water and PCM as energy storage material. Type of material selection and design arrangement also contribute to the performance of solar thermal collector. The aim of this research is to enhance the thermal performance of energy storage on Evacuated Glass-Thermal Absorber Tube Collector (EGATC) for air heating application. The performance study has been conducted to measure the outlet temperature and energy storage rates as per indoor setup under the artificial solar radiation on the effect of parameters such as inner absorber surface area air contact (perforated fins), outer absorber selective coating surface, outer absorber wall thickness, double layer non vacuum glass tube, single layer transparent outer glass tube and single layer thin film inner glass tube. The results showed that the performance of temperature outlet, energy store and energy buffer increase at wind speed 0.9 m/s, zero (0) perforated fin, non-coating outer absorber and 2mm outer absorber wall thickness. It was also demonstrated that a double layer vacuum glass tube showed a better thermal performance enhancement compared with double layer non-vacuum glass tube, single layer transparent outer glass tube and single layer thin film inner glass tube. This concluded that EGATC performance can be increase with those respective parameters.

Thermal model of bifacial silicon photovoltaic modules with different backsheets under outdoor conditions

ABSTRACT Bifacial silicon photovoltaic (PV) modules have obvious advantages in energy production compared to monofacial silicon PV modules because of the excess gain due to irradiance from the rear side. The double transparent material structure of bifacial modules improves the long-term durability compared to traditional glass-backsheet modules. In this paper, the thermal characteristics of both double glass (GG) and glass-transparent material (GT) bifacial modules are mathematically studied, and the limitation of former thermal models that determined the operating temperature without considering the bifaciality and rear irradiance factors is noted. After adding bifaciality and rear irradiance parameters into the new model, 2 groups of 32 bifacial PV modules were chosen to conduct indoor and outdoor tests from 1st Jan 2020 to 31st Dec 2020 in Yinchuan, China. Based on the whole year outdoor measured data, the operative transfer coefficients in the new model were iteratively computed through MATLAB for the optimized values under minimization of the root mean square error (RMSE). The results of the new model fit perfect well with the measured data for both the GG and GT modules, with RMSEs of 2.678 and 2.543, respectively. To verify the adoption of the new model under different conditions, four types of typical weather were analyzed, and the minimum RMSEs were 1.238 and 1.149 under median irradiance weather.

Reentrant double glassy states and simultaneous presence of short- and long-range ordering in metamagnetic Co-doped Bi0·5La0·5Fe0·5Mn0·5O3 multiferroic

A study of the structural and magnetic properties of Bi0·5La0·5Fe0·45Co0·05Mn0·5O3 is presented in the article. We report the rare observations of two glassy transitions below the long-range ordering temperature along with the metamagnetic transitions at low temperatures. Frequency and DC field dependence of AC susceptibility and isothermal relaxation of remnant magnetization studies have all shown the slow spin dynamics for the compound. Interestingly, in the glass phase of the materials, metamagnetic transitions of the antiferromagnetic spins were found which indicate the coexistence of the long-range ordered phase along with the short-range ordered glassy phase. The double cluster glass phases can be comprehended, from the relaxations of the spin clusters arising from the competing magnetic interactions present in the system. Moreover, the roles of additional exchange interactions which are brought to the system by Co doping are also considered in explaining the observed double cluster glass transitions.

Benefitting from Solar Energy Due to Different Emissivity Levels of Multiple Glass Windows for Buildings

In the study, firstly, heat transfer coefficients of windows were calculated according to the highest and lowest emissivity values. Secondly, monthly average solar radiation values were determined. The heat transfer coefficient calculated for double, triple and quadruple glass windows. Thirdly, the solar radiation in the south, north and east/west directions of the five climatic zones were multiplied by the shading factor, surface area and the solar energy factor of discrete buildings. Thus, the solar energy gain value for the heating period and solar energy losses for cooling period was determined. Finally, passive solar energy gains are calculated during the heating and cooling period for all climate zones. It has been calculated that in the fifth climatic zone in south direction, heat loss from windows with 0.05 emissivity can be provided with passive solar energy by 167.9% in double-glazed windows, 258.7% in triple-glazed windows and 349.1% in quadruple-glazed windows.

Analysis of the Thermal Characteristics and Energy performance of Electro Chromic Glazing window

Windows and shading devices occupy an essential part between inside and outside environment of buildings, for providing interior air quality and optimization of lighting and HVAC energy consumption. This paper aims to perform the thermal performance of double pane Electrochromic window (ECW) using Finite Element Method and the energy performance using the Building Information Modelling (BIM) tool. The thermal model of the ECW is simulated in COMSOL Multiphysics. Double pane glass with and without electrochromic (EC) layer is analyzed to obtain the average and maximum surface temperature between the top and bottom layers of the glazing. It is observed that the maximum temperature gradient is observed with EC layer. The energy performance with a double glazing and ECW for warm and humid climate is evaluated using eQUEST DOE tool. A 30 % reduction is observed in the annual energy consumption with an ECW compared to that with a double-glazing window. In addition, during the monthly evaluation of energy consumption, there is 10% reduction with the ECW compared to baseline. The appreciable thermal characteristics and the energy performance of the EC glazing proves it to be an alternative solution for normal window glazing in automated buildings for thermal comfort and lesser cooling load demand.

Research on the thermal comfort of the elderly in rural areas of cold climate, China

ABSTRACT At present, the thermal comfort evaluation index has not been differentiated for different types of people, and the indoor thermal environment of the residences in rural areas of cold climate, China, urgently need attention. In this study, indoor living environment of rural residences in Hebei and Tianjin were measured to obtain typical residential forms, building thermal parameters and thermal comfort parameters of the elderly. At the same time, 152 elderly people were investigated by questionnaire to obtain the subjective evaluation such as thermal sensation. In addition, the optimization suggestions of plane structure, building envelope and window to wall ratio were put forward through software simulation. The results show that the thermal neutral temperature of the rural elderly people in cold zone is 16.74°C, and they are more sensitive to the temperature below 15.67°C and more slowly to the temperature above 15.67°C. The recommended thickness of wall insulation layer is 80–100 mm, and that of roof insulation layer is 60–80 mm. Double layer glass should be used. Wood window frame has better thermal insulation effect than aluminium frame, and the recommended window to wall ratio is 0.28.

Improving the performance of a hybrid solar desalination system under various operating conditions

The issue of freshwater shortage is a general problem that touches almost all human beings, and everyone is trying to find creative and practical solutions to try to overcome this problem. In this paper, the proposed desalination system consists of a modified solar still (MSS), parabolic trough solar collector (PTSC), separation unit (SU), and two external condensers (EC). The idea of this proposed device is that the PTSC was utilized to heat the saline feed water to a temperature from which steam can be extracted, and then a separation is made for this steam from the remaining water that has risen in temperature and has not been evaporated to be used as feed water for MSS. Also, MSS has been modified by making all its walls (except for the back wall of the distiller) of glass to obtain a greater amount of absorbed solar radiation. Besides, a double glass cover for MSS was used instead of the single glass sheet to prevent the heat loss to the atmosphere through the glass cover. The double glass cover is two sheets of glass between which there is a slight vacuum pressure. Regarding the experimental tests conducted through July 2021, the main conclusions of this work can be pointed. It was revealed that at 12:00, the maximum water temperature of PTSC was 55 °C at 20 L/hr (0.33 L/min), where the solar radiation was 1050 W/m². Besides, the effectiveness of PTSC was 60%, and the total accumulated productivity of PTSC was 83 L/daytime (daytime = 9 hrs). Moreover, the total accumulated productivities of conventional solar still (CSS) and MSS with double glass cover were 3330 and 2325 mL/m².daytime, respectively. Therefore, the productivity of MSS with double glass cover was smaller than that of the CSS by about 30%. In addition, the total accumulated freshwater distillate of CSS and MSS with double glass and condenser was 3370 mL/m².daytime and 6150 mL/m².daytime, respectively. As a consequence, the productivity of MSS with double glass and condenser was more than that of CSS by around 82.50%. In addition, the thermal and exergy efficiencies were 31% and 2.54%, respectively for CSS and 47.5% and 3.95%, respectively for MSS with double glass and condenser. Besides, the total productivity of the hybrid system (PTSC and MSS together) was reported as 91.0 L/daytime. Also, the cost of distilled water of proposed hybrid system is 0.008 $/L, and payback period of costs on proposed system is three months. Moreover, the environmental parameters of EPF, ϕCO2, and Z′ for MSS are slightly more than the double of that for CSS.

Compatibility and Thermal and Structural Properties of Poly(l-lactide)/Poly(l-co-d-lactide) Blends

To explicate the interaction processes between poly(l-lactide) (PLLA) and poly(l-co-d-lactide) (PLDLA) in their blends, a series of high-molecular-weight PLDLA-m polymers (where m represents the percentage of l-lactate units) were prepared by ring-opening polymerization at different feed ratios of l- to d-lactides and blended with highly optically pure PLLA by solution blending. The compatibility and thermal and structural properties of the PLLA/PLDLA-m blends were investigated by differential scanning calorimetry (DSC) and field emission scanning electron microscopy (FE-SEM) in detail. The PLLA/PLDLA-m blends with m = 60–20 wt % were only partially compatible because obviously double glass transitions were detected in DSC curves and multiphase structures were observed in SEM micrographs. The compatibility between PLLA and PLDLA-m decreased as the l-lactate unit content in PLDLA-m decreased. Crystallization of the PLLA phase in the PLLA/PLDLA-m blends was restricted by PLDLA-m at m = 95–40 wt % (the restriction was strongest at m = ∼70 wt %); however, it was enhanced as the l-lactate unit content decreased at m ≤ 40 wt %. The PLLA/PLDLA-m blends demonstrated weak-to-strong hydrogen-bonding interactions as the l-lactate unit content decreased at m ≤ 80 wt %. The PLLA/PLDLA-m blends can form not only a eutectic but also individual crystal structures of PLLA and PLDLA-m at m ≥ 80 wt %, while the formation of individual crystals of PLLA, PLDLA-m, and stereocomplexed polylactide (sc-PLA) is favored at m ≤ 15 wt %.

Probing the effect of a glass network on the synthesis and luminescence properties of composite perovskite glasses [Invited

All-inorganic cesium lead bromide perovskite nanocrystals (PNCs) are highly promising candidates for various optoelectronic and photonic devices. However, poor stability upon exposure to moisture and lead toxicity issues significantly limit their applications. A modern and promising strategy on resolving these issues is the encapsulation of highly luminescent (PNCs) within transparent inorganic oxide glasses. While the encapsulation procedure effect on the development and properties of the so-formed PV-Glasses has been explored in detail, there is lack of understanding the influence of the selected glass composition and network type on the outcome of the synthesis. Herein we report on the synthesis and photoluminescence properties of composite perovskite-glasses upon growing all-inorganic lead halide perovskites within three different types of inorganic oxide glasses. When a silver metaphosphate glass matrix is used it is revealed that the low glass transition temperature of the phosphate glass limits significantly the temperature range of the required post-melting annealing treatment, while the lead salt precursors react with the phosphate entities of the network destroying the stoichiometry of the PNCs. As a result the formation of PNCs is hindered. As a consequence, a double network former borophosphate glass was employed as a suitable host. While annealing treatments at higher temperature were facilitated in this case, it is found that the high silver content becomes an obstacle for the perovskite formation. In view of these findings, cesium lead bromide (CsPbBr3) and cesium lead iodide (CsPbI3) composite perovskite borate glasses were synthesized and found to be suitable hosts. Indeed, such composite glasses exhibit interesting photoluminescence properties that are compared with those of PNCs outside the glass matrix.

Thiol-Ene Coupling of High Oleic Sunflower Oil towards Application in the Modification of Flexible Polyurethane Foams.

High oleic sunflower oil-based polyol was obtained by thiol-ene coupling and applied in the preparation of flexible polyurethane foams. The photochemically initiated thiol-ene click reaction was carried out under UV irradiation using 2-mercaptoethanol. Bio-based polyol with hydroxyl value of 201.4 mg KOH/g was used as 30 wt% substituent of petrochemical polyether polyol in the formulations of flexible foams. Both reference foams, as well as foams modified with bio-based polyol, were formulated to have various isocyanate indices (0.85, 0.95, 1.05). Flexible foams were compared in terms of their thermomechanical properties and analyzed using FT-IR and SEM microscopy. Modification with bio-based polyol resulted in foams with superior compression properties, higher support factor, and lower resilience than reference foams. TGA and FT-IR curves confirmed the presence of urethane/urea and ether linkages in the polyurethane matrix. Moreover, double glass transition temperature corresponding to soft and hard segments of polyurethane was observed by DSC proving the phase-separated morphology.

Experimental investigation of a passive type solar still with double wedge shape glass cover

Solar thermal energy-based desalination systems such as solar stills deliver fresh distilled water at zero carbon emission levels. In this paper, passive type solar still with double wedge shape glass cover is experimentally investigated for its performance, and economics factor is analyzed. This new design solar still model is Twin Wedge Solar Still (TWSS). The economics of the system concerning cost per litre is also presented. The performance of TWSS is weighed against that of a Conventional Solar Still (CSS) in this study. The novel glass cover shape design of the TWSS increases the condensation surface area, increasing the condensation rate, thus enabling the TWSS to deliver 2.68 L of fresh distilled water per m2 area of the solar still. The CSS yielded only two-third of TWSS for the same constraints, thus making TWSS 51.5% more efficient than CSS. The economic analysis shows that TWSS possess a lesser cost per litre rate (0.028 $/l) than CSS, which aids it to achieve a shorter payback period (one year for TWSS). The simple and symmetrical design of the TWSS makes it more advantageous than other unique and new design solar stills. As a future study, the integration of thermal energy storage components in the basin structure is proposed to increase the vaporation rate of the TWSS.

Fast simulation of dynamic heat transfer through building envelopes via parareal algorithms

In this article, two efficient time-parallel algorithms, the classical parareal algorithm and the parareal waveform relaxation (PWR) algorithm, were constructed and investigated for dynamic heat transfer through building envelopes. They were first compared with the response factor method and harmonic response method to show their reliability. Then the simulation results and parallel performance of the two parareal algorithms were investigated through examples about a roof, a double glass façade (DGF), and a wall with a patented aerogel insulating layer. In all simulations, the computing time of the PWR algorithm decreases by 26–30% compared to that of the classical parareal algorithm. The results for speedup and parallel efficiency also indicate that the PWR algorithm is more efficiency than the classical parareal algorithm.

Experimental evaluation of solar multistage direct contact membrane distillation system for water desalination

The performance of a solar-heated multistage direct contact membrane distillation system was experimentally evaluated for sustainable water production. Parallel and series connections of three DCMD stages for the feed and permeate streams were tested and compared. A mathematical model for a double glass evacuated tube solar collector was developed to predict the temperature variation of the stagnant feed water solar tank during heating. Results demonstrate the sustainability of water production using the integrated solar DCMD desalination system. Parallel connection of system stages is more productive compared to series connection. The system flux is decreasing over the day hours following the decreasing feed water temperature due to higher energy consumed by the DCMD desalination process compared to the solar energy received by the single solar collector. However, the system showed a very good level of water production sustainability over the day hours. The average fluxes from 9 AM to 6 PM are 51.6 kg/m2.h for the parallel multistage system and 22.1 kg/m2.h for the series multistage system, corresponding to an average solar tank (feed water) temperature of 66 °C. The parallel three-stage solar MD system produced 9 L of fresh water, with specific thermal energy consumption of about 1770 kWh/m3.

Analisis Kinerja Kolektor Distilasi Surya Kaca Ganda Dengan Heat Absorber

Solar distillation is a water distillation technology to get fresh water from sea water by evaporating sea water by heating it with solar energy, which then condenses the water vapor to get fresh water. The use of heat absorbers is to increase the absorption of solar energy and lift water to the surface of the heat absorber material to be evaporated. This research was conducted to determine the effect of using various heat absorbers (charcoal, pumice and white sand) on the quantity of fresh water produced by a double glass solar distillatory and to determine the performance of a double glass solar distillation collector with various heat absorbers. This research was carried out by direct observation for data collection, direct testing was carried out on a double glass distillatory with various heat absorbers, for accuracy the research was carried out simultaneously for all types of heat absorbers in the alternative energy laboratory of the Department of Mechanical Engineering at the State Polytechnic of Ujung Pandang for 5 days. The test was carried out from 08.00 WITA to 17.00 WITA by recording data every 30 minutes. Based on the research and data analysis conducted, the average condensate volume for charcoal heat absorber is 157 ml, pumice stone is 141 ml and white sand is 80.8 ml. % and white sand 3,784%.

Studying Energy Performance and Thermal Comfort Conditions in Heritage Buildings: A Case Study of Murabba Palace

Heritage buildings are significant historical and architecture added value, which requires deep and precise preliminary brainstorming when considering upgrading or retrofitting these valuable buildings. In this study, we opted to highlight some passive design architecture interventions to improve the thermal comfort and the required cooling energy for buildings. The Murabba Palace in Riyadh was selected as a case study. DesignBuilder software was used to evaluate the energy performance of ten passive architectural design alternatives throughout different seasons in an attempt to improve the energy performance and thermal comfort of heritage buildings. The ten passive design scenarios encompassed double low-E glass, double reflected glass, double low-E glass and double wall with an air gap, double low-E glass and double wall with thermal insulation, double low-E glass and double wall with lightweight thermal insulation, double low-E glass and double wall with sprayed foam insulation, double reflected glass and double wall with an air gap, double reflected glass and double wall with thermal insulation, double reflected glass and double wall with lightweight thermal insulation, and double reflected glass and double wall with sprayed foam insulation. The results show that using double low-E glass and applying a double wall with polystyrene thermal insulation can enhance the thermal comfort inside the building and reduce the energy performance and CO2 emissions to 17% and 9%, respectively.