137 research outputs found

    Investigation of Different Window and Wall Materials for Solar Passive Building Design

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    AbstractThe energy consumption associated with the cooling of the buildings is huge. In India buildings consume about 33% of country's power production for cooling and day lighting. The building enclosures such as walls, roofs and glasses play very vital role in reducing cooling loads in the buildings. The proper combination of window glass materials and wall materials can cut down the cooling costs extensively. In the present work, five different glass materials such as clear, bronze, grey, green and blue-green glass materials were selected and four different building materials such as burnt brick, cinder concrete, dense concrete and fly ash brick either side plastered with cement plaster were selected. Total twenty building models with various combinations of window glass and wall materials were designed in licensed Design builder 4.3.0.039 version and thermal analysis was carried out in Energy plus 8.1 software package. Thermal performance of various building models in four different climatic zones such as hot and dry, temperate, warm and humid and composite were investigated. From the results of the study, it is observed that fly ash brick wall building model with grey window glass is found to be energy efficient in all Indian climatic zones from the reduced cooling load point of view among all studied combinations in East, West, North and South orientations. From the results it is observed that the fly ash brick buildings with grey glass window is observed to be the most energy efficient combination for reducing cooling loads as they gain the least heat gain in south orientation (21.51 kWh) for Ahmedabad region. The results of the study help in designing energy efficient passive buildings

    Study of Unsteady State Thermal Characteristics of Homogeneous and Composite Walls of Building and Insulating Materials for Passive Cooling

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    Passive cooling is one of the methods to keep the building cool and to reduce the load on air conditioner. Passive cooling demands the study of the thermal characteristics like admittance, transmittance, decrement factor, time lag, surface factor and surface factor time lags. These characteristics were determined for both homogeneous and composite walls. The buildings are built with composite wall. This demands the study of thermal characteristics of composite wall. In this study, five building materials like Laterite stone, Burnt brick, Mud brick, Reinforced brick and Fly ash bricks were selected as homogeneous building materials. Five local Insulating materials such as Saw dust, Rice husk, Coir board, Jute felt and Jute fiber were selected to form the composite wall along with building materials. The composite walls were framed using the combination of building materials and insulation materials. Total hundred combinations of composite walls, without insulation (Configuration-A) and with insulation material located at inner side (Configuration-D), insulation material at mid plane (Configuration-C) and insulation material at outer side (Configuration-B) of the composite wall were studied. To study the thermal characteristics of such configurations of composite wall, one dimensional heat flow diffusion equation was solved using matrix algebra under periodic boundary conditions. The penetration length of thermal waves, the phase velocity of the heat wave in the wall and optimum fabric thickness of the selected building and insulating materials were calculated. From this study it is found that the decrement factors of the fly ash brick (0.401) and jute felt (0.4) are the least and the time lags of the fly ash bricks (8.15h) and jute felt (8.75h) are the highest among all the studied homogeneous building and insulating materials. Hence these two homogeneous materials are more effective building and insulating materials at suppressing temperature swings. It is summarized that insulation located at the inner surface (Configuration D) of the composite wall gives the lower time lags and higher decrement factors. This is the worst condition of insulating the wall among all the studied configurations. It is also concluded that fly ash brick composite walls with jute felt insulation located at the mid plane of the wall give greater time lags (11.17 h) and reinforced brick composite walls with rice husk insulation located at the inner side of the wall give lower time lag values (7.37h). It was also observed that fly ash brick composite walls with coir board insulation located at the outer side of the wall give the lowest value of decrement factor (0.17) and reinforced brick composite walls with jute fiber insulation located at the inner side of the wall give higher decrement factors (0.37). Fly ash brick composite walls with jute felt insulation located at the mid center plane of the wall are the most recommended composite walls among all the studied composite walls. Henceforth this composite wall is recommended for passive cooling

    A comparative assessment of the effects of fresh and saltwater on soluble proteins and surimi made from Hypophthalmichthys molitrix

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    Due to the special taste of the Silver carp, the fish is not used for production of Surimi. Researchers have shown that water soluble proteins in water and brine have significant effects on the taste, flavor and odor of the Surimi produced from the fish. In this study, the effects of washing minced meat of Silver carp with fresh water and brine with 1.5 and 2.5 percent salt for 5, 10 and 15 minutes on the taste of Surimi and its shelf life cold stored for 120 days were investigated. We prepared three lots of minced meat from silver carp and each lot was washed with fresh water and brine with 1.5 and 2.5 percent salt, for 5, 10 and 15 minutes. The extracted water soluble proteins from fresh water washing were 1.3, 2.7, and 4.01 and for brine were 2, 4.2, 6.3 and 2.96 5.92 and 9 percent of the total protein of the fish for 1.5% and 2.5% salt respectively. A taste panel ranked the Surimi made from minced meat after washing with 1.5% brine for 10 minutes as the best in terms of taste, flavor and odor. We recorded a change in protein content of the Surimi made from minced meat washed with fresh water and be and stored for 120 days at -18°C, from 17.02 to 16.46, 14.73 to 13.5 and 12.03 to 11.5%, respectively. TVN for the same samples were increased from 9.76 to 13.2, 8.43 to 12.10 and 7.03 to 1 Img/100g. Changes in peroxide value were zero to 1.9, zero to 1, and zero to 0.8 Milli-equivalents/1000g. The total count of the bacteria for these Surimi samples were between 15 to zero colonies after 120 days storage at 48 C. Data from the different chemical, microbial, and sensory quality measurement were subjected to one way Anova and Ducan's multiple range test and the results showed a significant difference between the treatments at P<0.05. For production of Surimi from washing minced meat of silver carp is better to wash minced meat with 1.5% brine for 10 minutes. The Surimi's nutrition rate including: Protein 16.83%; fat 2.2%; moisture 82.65% and ash 1.5%

    Beyond somatosensation: Mrgprs in mucosal tissues

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    Mas-related G coupled receptors (Mrgprs) are a superfamily of receptors expressed in sensory neurons that are known to transmit somatic sensations from the skin to the central nervous system. Interestingly, Mrgprs have recently been implicated in sensory and motor functions of mucosal-associated neuronal circuits. The gastrointestinal and pulmonary tracts are constantly exposed to noxious stimuli. Therefore, it is likely that neuronal Mrgpr signaling pathways in mucosal tissues, akin to their family members expressed in the skin, might relay messages that alert the host when mucosal tissues are affected by damaging signals. Further, Mrgprs have been proposed to mediate the cross-talk between sensory neurons and immune cells that promotes host-protective functions at barrier sites. Although the mechanisms by which Mrgprs are activated in mucosal tissues are not completely understood, these exciting studies implicate Mrgprs as potential therapeutic targets for conditions affecting the intestinal and airway mucosa. This review will highlight the central role of Mrgpr signaling pathways in the regulation of homeostasis at mucosal tissues

    A user-friendly and accurate machine learning tool for the evaluation of the worldwide yearly photovoltaic electricity production

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    While traditional methods for modelling the thermal and electrical behaviour of photovoltaic (PV) modules rely on analytical and empirical techniques, machine learning is gaining interest as a way to reduce the time, expertise, and tools required by designers or experts while maintaining high accuracy and reliability. This research presents a data-driven machine learning tool based on artificial neural networks (ANNs) that can forecast yearly PV electricity directly at the optimal PV inclination angle without geographic restrictions and is valid for a wide range of electrical characteristics of PV modules. Additionally, empirical correlations were developed to easily determine the optimal PV inclination angle worldwide. The ANN algorithm, developed in Matlab, systematically and quantitatively summarizes the behaviour of eight PV modules in 48 worldwide climatic conditions. The algorithm's applicability and robustness were proven by considering two different PV modules in the same 48 locations. Yearly climatic variables and electrical/thermal PV module parameters serve as input training data. The yearly PV electricity is derived using dynamic simulations in the TRNSYS environment, which is a simulation program primarily and extensively used in the fields of renewable energy engineering and building simulation for passive as well as active solar design. Multiple performance metrics validate that the ANN-based machine learning tool demonstrates high reliability and accuracy in the PV energy production forecasting for all weather conditions and PV module characteristics. In particular, by using 20 neurons, the highest value of R-square of 0.9797 and the lowest values of the root mean square error and coefficient of variance of 14.67 kWh and 3.8%, respectively, were obtained in the training phase. This high accuracy was confirmed in the ANN validation phase considering other PV modules. An R-square of 0.9218 and values of the root mean square error and coefficient of variance of 31.95 kWh and 7.8%, respectively, were obtained. The results demonstrate the algorithm's vast potential to enhance the worldwide diffusion and economic growth of solar energy, aligned with the seventh sustainable development goal

    Development and optimisation of treatment technologies for environmental pollution control

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    A number of sustainable and economically viable treatment methodologies have been developed and optimised to combat environmental pollution problems associated with the diversity and scattered nature of industries in Pakistan. The use of both electro-precipitation and electro-oxidation processes are shown to lead to the removal of dyes from textile effluent streams originating from various operations. The use of the electro-precipitation process, however, leads to a secondary disposal problem because sludge produced has to be disposed of safely. The use of an electrooxidation process does not produce sludge but is unable to remove some of the organic impurities from industrial textile effluent. Both processes do, however, result in colour removal from dye effluents with the degradation of dyes during electro-oxidation proceeding through the formation of different intermediate species before mineralization leading to complete mineralization in 30-40 minutes. Ames tests confirm that the treated effluent streams from both electro-precipitation and electro-oxidation processes are non-mutagenic. The electro-Precipitation process with mild steel anodes is also be used for the treatment of leather effluent streams to remove chromium by producing a mixed Cr(III) / Fe(III) hydroxide sludge. The same treatment process was successfully used for the simultaneous removal of dyes and chromium from mixed textile/leather effluent streams. The electro-precipitation process developed has been successfully tested on pilot scale at a textile mill in Faisalabad, Pakistan. A number of transition metal supported catalysts were shown to be ineffective in the oxidation of volatile organic compounds. For this reason a method of preparing platinum group metal catalysts on inert supports at low temperatures was developed and used to oxidise toluene, as an indicator of volatile organic compounds. The preferred catalyst support is y-A1203 which can be in the form of spheres or washcoated monoliths. In the case of y-A1203 spheres and the y-A1203 washcoated monolith complete oxidation of toluene was achieved at the relatively low temperatures of 236 and 2680C. A number of novel room temperature ionic liquids (RTILs) were synthesised, characterised and their potential application for selective extraction of copper from industrial wastes is also reported. The solubility studies of different metal oxides in the RTIL, 1-(2-cyanoethyl)-3-methylimidazolium bromide, show that it can be used for the selective extraction of copper from industrial waste samples containing other metal oxides. This RTIL has the ability to selectively dissolve, copper, copper oxide and copper sulfide when the reaction is carried out in the presence of water.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Floating PVs in Terms of Power Generation, Environmental Aspects, Market Potential, and Challenges

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    This is the final version. Available on open access from MDPI via the DOI in this recordLimited reserves of fossil fuels, rising environmental concerns, and a remarkable increase in electricity demand have led to the necessity of harnessing solar energy on a large scale. For this purpose, there has been a noticeable stimulation into photovoltaic power plants (PVPPs) over the last three decades, but the land requirement for PVPPs is still a handicap in many countries since valuable lands are considered for other purposes such as agriculture and livestock. For effective conservation of valuable lands and water resources, PVPPs are preferred to be installed on various water bodies such as oceans, seas, lagoons, lakes, rivers, dams, canals, wastewater treatment plants, irrigation ponds, fish farms, wineries, reservoirs, etc. PV systems on water bodies are called floating PVPPs, and they have outstanding advantages compared with land-based PVPPs including better energy generation owing to passive cooling effects, higher system efficiency and reliability, and lower dirt and dust accumulation on PV modules thus lower operating costs. There are also some significant environmental features provided by floating PVs. Shading effects due to PV coverage reduce water losses arising from evaporation. Moreover, algae growth is limited because of mitigated solar radiation, which yields better water quality. This review presents more insight on floating PVPPs in terms of several aspects such as electricity generation, system efficiency, reliability and sustainability, experimental applications and facilities in operation, water and carbon saving as well as challenges

    Metabolic phenotype of male obesity-related secondary hypogonadism pre-replacementand post-replacement therapy with intra-muscular testosterone undecanoate therapy

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    Aim: To explore the metabolic phenotype of obesity-related Secondary Hypogonadism (SH) in men pre- and post-replacement therapy with long-acting intramuscular (IM) testosterone undecanoate (TU). Methods: A prospective observational pilot study on metabolic effects of TU IM in male obesity-related SH (Hypogonadal [HG] group, n=13), including baseline comparisons with controls (Eugonadal [EG] group, n=15). Half the subjects (n=7 in each group) had Type 2 Diabetes Mellitus (T2D). Baseline metabolic assessment on Human Metabolism Research Unit: fasting blood samples; BodPod (body composition), and; whole-body indirect calorimetry. The HG group was treated with TU IM therapy for 6-29 months (mean 14.8-months [SD 8.7]), and assessment at the Human Metabolism Research Unit repeated. T-test comparisons were performed between baseline and follow-up data (HG group), and between baseline data (HG and EG groups). Data reported as mean (SD). Results: Overall, TU IM therapy resulted in a statistically significant improvement in HbA1C (9mmol/mol, P=0.03), with 52% improvement in HOMA%B. Improvement in glycaemic control was driven by the HG subgroup with T2D, with 18mmol/mol [P=0.02] improvement in HbA1C. Following TU IM therapy, there was a statistically significant reduction in fat mass (3.5Kg, P=0.03) and increase in lean body mass (2.9Kg, P=0.03). Lipid profiles and energy expenditure were unchanged following TU IM therapy. Comparisons between baseline data for HG and EG groups were equivalent apart from differences in testosterone, SHBG and BMR. Conclusion: In men with obesity-related SH (including a subgroup with T2D), TU IM therapy improved glycaemic control, beta cell function and body composition

    Screening for malnutrition in patients with gastro-entero-pancreatic neuroendocrine tumours : a cross-sectional study

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    Objectives To investigate whether screening for malnutrition using the validated malnutrition universal screening tool (MUST) identifies specific characteristics of patients at risk, in patients with gastro-entero-pancreatic neuroendocrine tumours (GEP-NET). Design Cross-sectional study. Setting University Hospitals Coventry & Warwickshire NHS Trust; European Neuroendocrine Tumour Society Centre of Excellence. Participants Patients with confirmed GEP-NET (n=161) of varying primary tumour sites, functioning status, grading, staging and treatment modalities. Main outcome measure To identify disease and treatment-related characteristics of patients with GEP-NET who score using MUST, and should be directed to detailed nutritional assessment. Results MUST score was positive (≥1) in 14% of outpatients with GEP-NET. MUST-positive patients had lower faecal elastase concentrations compared to MUST-negative patients (244±37 vs 383±20 µg/g stool; p=0.018), and were more likely to be on treatment with long-acting somatostatin analogues (65 vs 38%, p=0.021). MUST-positive patients were also more likely to have rectal or unknown primary NET, whereas, frequencies of other GEP-NET including pancreatic NET were comparable between MUST-positive and MUST-negative patients. Conclusions Given the frequency of patients identified at malnutrition risk using MUST in our relatively large and diverse GEP-NET cohort and the clinical implications of detecting malnutrition early, we recommend routine use of malnutrition screening in all patients with GEP-NET, and particularly in patients who are treated with long-acting somatostatin analogues
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