Effectiveness of using zeotropic working fluids in heat pumps

We analyze the thermodynamic cycles of heat pumps using monofluids and zeotropes are used as the working fluids. We show that selecting zeotropic fluids with favorable thermodynamic properties and substantially nonisotropic phase transformation processes (ΔT_ni > 10 K) is an effective way of making the thermal processes more efficient.     

Diazepam induced early oxidative changes at the subcellular level in rat brain

Binding of calcium to calmodulin (CAM) induces specific structural rearrangements in the whole protein molecule. Ca2+ organizes and stabilizes the four-domains structure of calmodulin in a helical, active conformation that can bind to its target proteins; the central helix remaining flexible is an essential condition for their bio-recognition. The conformation of calmodulin, and its efficacy to interact with target proteins, is profoundly altered when bound to metal ions other than calcium. As recently reported, the local structural changes of CaM, which occur upon aluminium binding, lead to the impairment of protein flexibility and to the loss of its ability to interact with several other proteins, which may decrease or inhibit the regulatory character of calmodulin. In this study we followed conformational changes occurring in the calmodulin molecule after aluminium binding using highly specific monoclonal antibodies (mAbs) able to differentiate between the conformational states of calmodulin, as well as mAbs which recognize aluminium free or bound to proteins. Under the same experimental conditions, mAb CAM-1, a Ca2+ conformation sensitive antibody raised against calmodulin, fails to recognize the calmodulin-aluminium complex, despite the presence of Ca2+, while the anti-Al antibodies show a maximal binding pattern towards their antigen. These data suggest that Al3+ ions bind to calmodulin in the presence of Ca2+ ions, leading to an inactive, reversible conformation, instead of its physiological active form. Alteration of the conformation of calmodulin imposed by Al binding may have possible implications in the neurotoxicity mechanism related to Alzheimer's disease.     

Expert system approach in design of mechanical components

The present investigation is aimed toward the development of knowledge-based aids for the design of mechanical systems. We have developed and implemented the knowledgebased aid system, which includes MEET and DPMED. The basic approach of MEET follows along the lines ofDesign=Refinement+ Constraint Propagation. This approach has been proven successful in the circuit design domain. Our attempts to utilize MEET have convinced us that we need to extend this methodology to solve mechanical design problems. The DPMED methodology has been applied to design gear-pairs, v-belts, bearings, and shafts. Rules for selecting materials, critical design criteria, and so on are incorporated as part of the rule-system. In order for DPMED to select the design parameter values within the feasible design space, design criteria need to be investigated. Based on these criteria and input/output specifications, DPMED attempts to perform parameter selections. DPMED uses a general hill-climbing algorithm to guide the search.     

Catalytic behavior of ruthenium in soybean oil hydrogenation

Soybean oil was hydrogenated with a carbon‐supported ruthenium catalyst (Ru/C) at 165 °C, 2 bar H₂ and 500 rpm stirring speed. Reaction rates, trans isomer formation, selectivity ratios and melting behaviors of the samples were monitored. No catalytic activity was found for the application of 10 ppm of the catalyst, and significant catalytic activity appeared at >50 ppm of active catalyst. The catalyst concentration had an effect on the reaction rate of hydrogenation, but the weight‐normalized reaction rate constant (k_c) was almost independent of the catalyst concentration at lower iodine values. Ru/C generated considerable amounts of trans fatty acids (TFA), including high amounts of trans 18:2, and also stearic acid, due to its very non‐selective nature. The selectivity ratios were found to be low and varied between 1.12 and 4.32 during the reactions. On the other hand, because of the low selectivity, higher slip melting points and solid fat contents at high temperatures were obtained than those for nickel and palladium catalysts. Another different characteristic of this catalyst was the formation (max 1.67%) of conjugated linoleic acid (CLA) during hydrogenation. Besides, CLA formation in the early stages of the reactions did not change very much with the lower iodine values.     

5G-V2X: standardization,architecture, use cases,network-slicing,and edge-computing

Wireless Networks - Vehicular communication is one of the critical technologies in intelligent transportation system to provide connectivity between vehicles, road side units, and pedestrians....     

Hybrid IG-FE method applied to cohesive fracture/contact in particle-filled elastomeric composites

International Journal of Mechanics and Materials in Design - In this paper, employing a new numerical framework, a 2D investigation is conducted on the effect of fiber-matrix contact/debonding on...     

Duty Cycling Centralized Hierarchical Routing Protocol With Content Analysis Duty Cycling Mechanism for Wireless Sensor Networks

In this paper, a Duty Cycling Centralized Hierarchical Protocol (DCCHP) has been proposed for wireless sensor networks. DCCHP is an energy efficient protocol that prolongs the lifetime of the network by applying a duty cycling mechanism named DCM that chooses the nodes that send unimportant data in a certain epoch to be candidates to be put to sleep. But if the proposed equations for choosing the cluster head nodes put any of them in a high priority it works in the active mode. When comparing DCCHP to the previously proposed LEACH-CS, LEACH-C protocols, using a simulation study, DCCHP in average extends the network lifetime 50% more than LEACH-CS and about 60% more than LEACH-C across a different number of nodes in the network scaled up to 1000 nodes. That is because DCCHP chooses the definite number of nodes of unimportant data to be switched to sleeping mode unlike LEACH-CS and unlike LEACH- C which keeps all nodes in active mode. Also an analytical study of energy consumption proves that DCCHP preserves energy consumption more than LEACH-CS and DCCHP. DCCHP has been proposed for applications with scarce resources.     

Impact of Weather Conditions and Dynamic Load Models on Steady State and Dynamic Response of Power System

This paper gives an insight on the effect of transmission line temperature variations, resulting from loading and weather conditions changes, on a power system＇s steady state and dynamic performance. The impact of dynamic load models on system stability is also studied. The steady-state and dynamic stability simulation results of a 39 bus system for constant line impedance （the traditional simulation practice） are compared to the results with estimated, but realistic, temperature varied line impedances using PSLF （positive sequence load flow） software. The modulated line impedances will affect the thermal loading levels and voltage profiles of buses under steady state response, while the dynamic results will show improved damping in electro-mechanical oscillations at generator buses.     

Reduced Model for Power System State Estimation Using Artificial Neural Networks

In this paper, a new technique using artificial neural networks for power system state estimation is presented. This method does not require network observability analysis and uses fewer measurement variables than conventional techniques. This approach has been successfully implemented on six-bus, 18-bus, IEEE 14-bus and IEEE 57-bus power systems and the results show that this method is very accurate and a lot faster than conventional techniques making it ideal for smart grid applications.     

Experimental and modeling analysis of asphaltene precipitation in the near wellbore region of oil wells

In this work, effect of reservoir temperature (in a range of 50–100°С) on the amount of asphaltene precipitation was determined. Rate of asphaltene precipitation was increased by increasing temperature. Damaged permeability of carbonate core samples was investigated at different asphaltene contents conducting core flood tests. The results showed the experimental and predicted data of damaged permeability ratio due to asphaltene precipitation matched. Moreover, the optimum mass concentration of components of the developed asphaltene inhibitor was determined by measuring interfacial tension on the boundary of oil and inhibitor solution. In addition, the change in the concentration of asphaltene inhibitor was simulated depending on the radial distance to well, production time and type of isotherm.