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91.
The present work reports on the microencapsulation of Nigella sativa seeds oil containing thymoquinone (TQ) by spray‐drying, using modified starch (MS) and maltodextrin (MD) mixture as wall materials aimed at producing functional yogurt. First, the impact of different ratios of MS/MD on microencapsulation efficiency (ME) and TQ retention was investigated. The highest ME (90.10%) was found in microcapsules prepared from emulsion with 80/20 ratio of MS/MD; however, the microcapsules prepared with 50/50 ratio was selected for considering TQ stability under storage conditions and functional yogurt production due to an acceptable ME (89.48%) and better TQ retention (61.12%). The results showed that the microcapsules stored at refrigerator temperature had the highest content of TQ after 4 weeks. Moreover, the results of chemical and sensory analysis suggest that N. sativa seeds oil microcapsules can be used for producing functional yogurt due to high stability of TQ and proper chemical and sensory properties.  相似文献   
92.
Cognitive radios (CRs) have been recently proposed for the problem of spectrum scarcity. The principle of CRs?? operation is based on the opportunistic access to the frequency spectrum mainly dedicated to primary users (PUs). The statistical time pattern of PUs?? channel usage and arrival can affect the usability of specific frequency bands for CRs. In this note, the effect of the arrival rate and channel holding time of PUs on the available times for CRs is analyzed. To this end, first, based on Poissonian arrivals, the available time for CRs is calculated. Then, assuming a gamma distribution for the inter-arrival times and a uniform distribution of channel holding time of PU in these intervals, the probability density function and moments of the available time for CRs are derived. Next, the effect of PUs statistical parameters on the average number of packets and the average symbol rate that a CR can transmit is analyzed. Also, taking that CR needs at least T seconds, the average waiting time is calculated.  相似文献   
93.
The present work aims to study effect of lactic acid concentration as complexing agent on surface roughness and nucleation morphology of electroless N?CP deposition. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) have been used to study nucleation morphology and surface roughness of deposition. Deposition process started at some initial priority growing centres independently distributed on the substrate. We found that the morphology and surface roughness of deposition strongly depends on the complexing agent concentration. Morphology of initial deposited centres with no concentration of lactic acid was in coniform structure. By increasing the complexing agent concentration, the structure of initial growing centres changed from coniform to nodular shape and the surface roughness of depositions decreased.  相似文献   
94.
Increasing energy demand has led to a substantial growth in the use of wind energy across the world, which can be attributed to the low initial and running costs and rapid and easy deployment of this technology. The development of hydrogen from wind energy is an excellent way to store the excess wind power produced, as the produced hydrogen can be used not only as clean fuel but also as input for various industries. Considering the good wind potentials of Yazd province, the variety of industries that are active in this area, and the central location of this province in Iran, which gives it ample access to major transport routes and other industrial hubs, hydrogen production from wind power in this province could benefit not only this region but the entire country. Given these considerations, we conducted a technical, economic, and environmental assessment of the potential for wind power generation and hydrogen production in Yazd province. Overall, the assessments showed that the best locations for harvesting wind energy in this province are Bahabad and Halvan stations. For these two stations, it is recommended to use EWT DW 52-900 turbine to take advantage of its higher nominal capacity to achieve higher electricity and hydrogen output and emission reduction. For Abarkoh and Kerit stations, which have a low wind energy potential, it is recommended to use small turbines such as Eovent EVA120 H-Darrieus. Also, economic and technical assessments showed that it is not economically justified to harvest wind energy in Ardakan station. The results of ranking the stations with the Step-wise Weight Assessment Ratio Analysis (SWARA) and Evaluation based on Distance from Average Solution (EDAS) techniques showed that Bahabad station was introduced as the best place to produce hydrogen from wind energy.  相似文献   
95.
Food Science and Biotechnology - Maillard-based conjugation may be a useful way of improving the functional properties of food biopolymers. In this study, covalent attachment of fish gelatin (FG)...  相似文献   
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98.
Building information modelling (BIM) teams, hereafter referred to as BIM-based construction networks, are teams whose possibly geographically dispersed members from various organisations and disciplines, perform project tasks on BIM-enabled projects. In recent years, BIM-based construction networks have progressively become the norm in executing BIM activities on projects. However, even though achieving BIM's full capabilities relies on effective collaboration among the team members in BIM-based construction networks, it is still a struggle for these members to collaborate. Nonetheless, only a few studies have been conducted to identify the barriers to strengthening team collaboration in BIM-based construction networks. To address this gap, the current study, by examining 73 journal articles on collaboration in BIM-based construction networks, builds upon a theoretical review of the literature. A conceptual model is presented to capture the main barriers to collaboration in BIM-based construction networks. The study benefits researchers as well as project managers. For researchers, the conceptual model provides an intermediate theory, namely, a theoretical basis to direct further knowledge creation attempts on the topic. In addition, the conceptual model supports project managers on BIM-enabled projects. That is, it simplifies the knowledge now available for practical applications enabling it to be translated into guidelines and practical instructions on real-life projects.  相似文献   
99.
Computational Economics - This paper presents the numerical solution of the Black–Scholes partial differential equation (PDE) for the evaluation of European call and put options. The proposed...  相似文献   
100.
Applied Intelligence - 3D Speckle tracking techniques are used to quantify cardiac deformation in 3D echocardiographic images. Elastic image registration methods are successful in solving 3D...  相似文献   
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