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71.
In recent decades, researchers have always considered the production of modified bitumen that could perform suitably in both high and low temperatures. One bitumen modifier is styrene butadiene styrene (SBS) polymer. Because bitumen modified with styrene butadiene styrene polymer does not show expected field performance in high and low temperatures largely due to phase separation of bitumen and polymer, the present research study is an attempt to use the composite of nano-SiO2 and styrene butadiene styrene polymer in modification of bitumen and analyze its high-temperature performance. The study revealed that adding nano-SiO2 to bitumen modified with SBS polymer resulted to an improvement of complex modulus, phase angle, resistance potential against rutting, storage modulus, loss modulus, and high-temperature functional performance in general. Additionally, the study uncovered that adding nano-SiO2 with 3% and 4% of bitumen weight, compared with other composites, considerably improved the high-temperature functional performance of bitumen modified with styrene butadiene styrene polymer. As 4.5%SBS+4%nano-SiO2 could not estimate less than 3 Pa.sec rotational viscosity in 135°C, 4.5%SBS+3%nano-SiO2 is offered as the optimal composite. The study is the first one in its own type in the world and is, therefore, innovative.  相似文献   
72.
Fenugreek seeds were germinated, soaked and roasted and were evaluated for nutritional properties. Raw and processed fenugreek seeds were used to develop snack product. Snacks were examined for the sensorial, functional, antinutritional properties and in vitro digestibility. Using sensory analysis, 5% level of substitution of raw and processed fenugreek was accepted for the development of extruded snacks. Lateral expansion was highest for snacks prepared from processed fenugreek (163.0% to 206.1%) than raw fenugreek (162.5 to 168.7%), and vice versa for bulk density. The antioxidant activity and total phenolic content were highest for snacks prepared from germinated fenugreek (7.30% to 9.87% and 1.352 to 3.561 mg GAE g−1 of sample) and lowest for snacks prepared from raw fenugreek (6.68% to 7.03% and 1.29 to 2.76 mg GAE g−1 of sample). Not only extrusion but also processing such as soaking, roasting and germination reduced the antinutritional content of the snack product. Both in vitro digestibilities increased with extrusion cooking. In vitro digestibility was also found to be higher in snacks prepared from processed fenugreek than raw fenugreek. Therefore, development of such functional foods using processed fenugreek would raise the consumer demand and benefit the population by increasing the health status.  相似文献   
73.
The vibration analysis of rotating, functionally graded Timoshenko nano-beams under an in-plane nonlinear thermal loading is studied for the first time. The formulation is based on Eringen's nonlocal elasticity theory. Hamilton's principle is used for the derivation of the equations. The governing equations are solved by the differential quadrature method. The nano-beam is under axial load due to the rotation and thermal effects, and the boundary conditions are considered as cantilever and propped cantilever. The thermal distribution is considered to be nonlinear and material properties are temperature-dependent and are changing continuously through the thickness according to the power-law form.  相似文献   
74.
A new system for cold atmospheric pressure plasma (CAPP) generation was designed and characterised. The effects of voltage (10, 15, 20 kV), frequency (10, 15, 20 kHz), gas flow rate (3, 5, 7 L min−1) and percentage of oxygen (0%, 0.5%, 1%) on the plasma jet length (PJL) were investigated. Then, different volumes (5, 10, 15 mL) of sour cherry juice were treated by CAPP to compare their physicochemical properties (colour and pH), Escherichia coli count, and bioactive compounds with samples treated by the conventional process. According to the results, PJL was increased by increasing the voltage and frequency and then remained constant. Also, PJL increases and then decreases by increasing the gas flow rate. Furthermore, CAPP treatment reduced E. coli count but did not alter the colour and pH of samples. Moreover, increasing the voltage, plasma treatment duration, and oxygen percentage enhanced the inactivation of E. coli. The best sterilisation effect was 6-log cycle decrease in E. coli count which was achieved at a voltage of 19.6 kV, an oxygen concentration of 1%, and a gas flow rate of 4.5 L min−1. Besides, the total phenol content of juice was 277 GAE/100 g and was changed to 279 and 359 after plasma treatment and conventional process, respectively.  相似文献   
75.
76.
To develop suitable sealants for intermediate temperature solid oxide fuel cells (IT-SOFC), glasseceramics based on the CaO-BaO-B2O3-Al2O3-SiO2 system were studied. Coefficient of thermal expansion (CTE), glass transition temperature (Tg) and dilatometric softening point temperature (Td) of specimens were determined by means of dilatometer analysis and crystallization temperature was measured by differential thermal analysis (DTA). Also, crystallization behavior during prolonged heat-treatment and microstructure properties were studied by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Electrical properties were measured at different temperatures, and the results showed a high resistance (>10 4Ω) at the SOFC operation temperature (600-800℃). Moreover, mechanical properties of heat-treated specimens (1, 10, 30, 50 h) were measured. Microstructure investigation revealed a well-adhered bonding between the sealant glasseceramic electrolyte and glass.  相似文献   
77.
The Earth to air heat exchanger (EAHE) is an effective passive cooling and heating system for buildings. This paper studied numerically the potential for reduction in energy consumption for cooling and heating loads for a residence equipped with an EAHE system in the climate of Nasiriya city, which is located in southern Iraq and at 31.7°N and 45.8°E, latitude and longitude, respectively. Also, this paper presents a study about the thermal performance of three types of EAHE systems, system 1, consisting of one layer of EAHE and buried at an available area of house garden with 3‐m depth, system 2, at the same site of system 1, but with two layers of EAHE at two depths, 3 and 4 m, and finally, system 3, buried along the area of the house at a depth of 3 m. First, the built numerical model was validated against experimental results, and the results of the comparison showed good agreement. The electricity consumption for cooling and heating of the house is calculated with and without the EAHE system. The results showed that with using EAHE, there is a considerable saving in energy and saving in the cost of electricity consumption, which reached 376 329 IQD ($301.11) over 1 year for system 2.  相似文献   
78.
Microsystem Technologies - Nonlinear free/forced vibration of a functionally graded graphene nanoplatelet (GNP) reinforced microbeam having geometrical imperfection which is rested on a non-linear...  相似文献   
79.
A new procedure for environmental targeting of co-generation system is presented. The proposed method is based on the concepts of pinch technology for total site targeting of fuel, power, steam, environmental impacts and total annualized cost with considering emissions taxes. This approach provides a consistent, general procedure for determining mass flow rates and efficiencies of the applied turbines. This algorithm utilizes the relationship of entropy with enthalpy and isentropic efficiency. Also, the life cycle assessment (LCA) as a well-known tool for analyzing environmental impacts on a wide perspective with reference to a product system and the related environmental and economic impacts have been applied. In this regard, a damage-oriented impact analysis method based on Eco-indicator 99 and footprints analysis was considered. In addition, the present work demonstrates the effect of including both sensible and latent heating of steam in the extended Site Utility Grand Composite Curve (ESUGCC). It is shown that including sensible heating allows for better thermal matching between the processes. Furthermore, the other representation YSUGCC as the other form of Site Utility Grand Composite has been proposed. Two case studies were used to illustrate the usefulness of the new environmental targeting method.  相似文献   
80.
Plants, being sessile, face an array of biotic and abiotic stresses in their lifespan that endanger their survival. Hence, optimized uptake of mineral nutrients creates potential new routes for enhancing plant health and stress resilience. Recently, minerals (both essential and non-essential) have been identified as key players in plant stress biology, owing to their multifaceted functions. However, a realistic understanding of the relationship between different ions and stresses is lacking. In this context, ionomics will provide new platforms for not only understanding the function of the plant ionome during stresses but also identifying the genes and regulatory pathways related to mineral accumulation, transportation, and involvement in different molecular mechanisms under normal or stress conditions. This article provides a general overview of ionomics and the integration of high-throughput ionomic approaches with other “omics” tools. Integrated omics analysis is highly suitable for identification of the genes for various traits that confer biotic and abiotic stress tolerance. Moreover, ionomics advances being used to identify loci using qualitative trait loci and genome-wide association analysis of element uptake and transport within plant tissues, as well as genetic variation within species, are discussed. Furthermore, recent developments in ionomics for the discovery of stress-tolerant genes in plants have also been addressed; these can be used to produce more robust crops with a high nutritional value for sustainable agriculture.  相似文献   
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