Phase Diagram,Equilibrium Data,and Correlation for Aqueous Two-Phase System Formed by Tetrahydrofuran and Sorbitol

Theoretical Foundations of Chemical Engineering - The importance of aqueous two-phase systems has been increased recently as a method with greater performance capability in separation and...     

On a new adaptive sliding mode control for MIMO nonlinear systems with uncertainties of unknown bounds

This paper proposes a new approach of adaptive sliding mode controller designs for multiple‐input multiple‐output nonlinear systems with uncertainties of unknown bounds and limited available inputs. The goal is to obtain robust, smooth, and fast transient performance for real sliding mode control so that the phenomena of the slow response and the gain overestimation in most adaptive sliding mode controller designs can be greatly improved. We introduce an Integral/Exponential adaptation law with boundary‐layer targeting the reduction of the chatter levels of the sliding mode by significantly reducing the gain overestimation while simultaneously speeding up the system response to the uncertainties. The gain is further reduced when the system state is in the boundary layer. The simulation and experimental results demonstrate the proposed design. Copyright © 2016 John Wiley & Sons, Ltd.     

Household Activity Pattern Problem with Autonomous Vehicles

Networks and Spatial Economics - The pace of changes in automating cars has sped up in the last few decades. Autonomous Vehicles (AVs) will dramatically change the future of transportation, and...     

An investigation on the application of process control agents in the preparation and consolidation behavior of nanocrystalline silver by mechanochemical method

In this paper, the effect of various amounts and types of process control agent (PCA), i.e., stearic acid (SA) and ethylene bis-stearamide (EBS), in the production and consolidation behavior of nanocrystalline silver prepared by mechanochemical reduction of Ag₂O by graphite was studied. The structural evolution and morphology of powders were investigated using XRD, HRSEM and particle size analyzer techniques. The results showed the nanocrystalline Ag formed after 25 h of milling and the addition of PCA prolonged the synthesis process time. Also, the effect of EBS on prevention of the excessive cold welding of ultra-fine Ag particles in the final stages of milling was more serious than SA. In fact, the presence of PCA effectively inhibited the creation of coarse Ag particles and finally decreased the crystallite size to 14 nm. Moreover, with the addition of PCAs, the Brinell hardness of sintered Ag samples was considerably increased.     

The nanostructure evolution of Ag powder synthesized by high energy ball milling

In this paper, nanostructured silver with an average crystallite size of 28 nm and internal strain of 0.44% was synthesized by mechanochemical reduction of Ag₂O using graphite in a high energy planetary ball mill. XRD, SEM and TEM techniques were used to characterize the structural evolution and morphological changes of products. The results showed that the reaction is progressed by a nucleation and growth mechanism process. Although the changes of crystallite size and internal strain in Ag₂O were regular during the milling, there was an irregularity in the aforementioned parameters of Ag particles. This irregularity was probably owing to the progressive generation of silver during the milling.     

A practical privacy-preserving targeted advertising scheme for IPTV users

In this work, we present a privacy-preserving scheme for targeted advertising via the Internet Protocol TV (IPTV). The scheme uses a communication model involving a collection of subscribers, a content provider (IPTV), advertisers and a semi-trusted server. To target potential customers, the advertiser can utilize not only demographic information of subscribers, but also their watching habits. The latter includes watching history, preferences for IPTV content and watching rate, which are periodically (e.g., weekly) published on a semi-trusted server (e.g., cloud server) along with anonymized demographics. Since the published data may leak sensitive information about subscribers, it is safeguarded using cryptographic techniques in addition to the anonymization of demographics. The techniques used by the advertiser, which can be manifested in its queries to the server, are considered (trade) secrets and therefore are protected as well. The server is oblivious to the published data and the queries of the advertiser as well as its own responses to these queries. Only a legitimate advertiser, endorsed with so-called trapdoors by the IPTV, can query the cloud server and access the query results. Even when some background information about users is available, query responses do not leak sensitive information about the IPTV users. The performance of the proposed scheme is evaluated with experiments, which show that the scheme is practical. The algorithms demonstrate both weak and strong scaling property and take advantage of high level of parallelism. The scheme can also be applied as a recommendation system.     

Adaptive sliding mode control – convergence and gain boundedness revisited

This paper reviews the main adaptive sliding mode controller (ASMC) designs for nonlinear systems with finite uncertainties of unknown bounds. Different statements of convergence referring to uniformly ultimate boundedness (UUB), asymptotic convergence (AC) and finite-time convergence (FTC) for ASMC shown in recent papers are analysed. Weaknesses and incomplete proofs apropos FTC are pointed out. Thereafter, a new approach is proposed to successfully demonstrate FTC of the so-called sliding variable. We identify a compensating phase and a reaching phase during the ASMC process. A new explicit form for estimating the upper-bound reaching time is provided for any bounded perturbation. An amended form of the real ASMC is recalled showing improved accuracy and chattering reduction. Finally, numerical and experimental applications are performed to convey the discussed results.     

Preparation and kinetic modeling of β-Co(OH)2 nanoplates thermal decomposition obtained from spent Li-ion batteries

An advanced solid-state kinetic analysis was used to investigate the thermal decomposition kinetic modeling of the cobalt hydroxide nanoplates synthesized from spent lithium-ion batteries (LIBs). The as-synthesized and calcined products were characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermal analysis (DSC-DTA-TGA), and scanning electronic microscopy (SEM). Kinetic analysis showed that complex decomposition of β-Co(OH)₂ in air occurred through two consecutive reactions in the 120–260 °C temperature interval. The reaction mechanism of the whole process can be kinetically characterized by two successive reactions: a phase boundary contracting reaction followed by a Prout-Tompkins autocatalytic equation. Mechanistic information obtained by the kinetic study was found in good agreement with FT-IR and SEM results.     

Microfluidic Synthesis of Ultrasmall Chitosan/Graphene Quantum Dots Particles for Intranasal Delivery in Alzheimer's Disease Treatment

Nanoparticles (NPs) based therapies for Alzheimer's disease (AD) attract interest due to their ability to pass across or bypass the blood-brain barrier. Chitosan (CS) NPs or graphene quantum dots (GQDs) are promising drug carriers with excellent physicochemical and electrical properties. The current study proposes the combination of CS and GQDs in ultrasmall NP form not as drug carriers but as theranostic agents for AD. The microfluidic-based synthesis of the CS/GQD NPs with optimized characteristics makes them ideal for transcellular transfer and brain targeting after intranasal (IN) delivery. The NPs have the ability to enter the cytoplasm of C6 glioma cells in vitro and show dose and time-dependent effects on the viability of the cells. IN administration of the NPs to streptozotocin (STZ) induced AD-like models lead to a significant number of entrances of the treated rats to the target arm in the radial arm water maze (RAWM) test. It shows the positive effect of the NPs on the memory recovery of the treated rats. The NPs are detectable in the brain via in vivo bioimaging due to GQDs as diagnostic markers. The noncytotoxic NPs localize in the myelinated axons of hippocampal neurons. They do not affect the clearance of amyloid β (Aβ) plaques at intercellular space. Moreover, they showed no positive impact on the enhancement of MAP2 and NeuN expression as markers of neural regeneration. The memory improvement in treated AD rats may be due to neuroprotection via the anti-inflammation effect and regulation of the brain tissue microenvironment that needs to be studied.     

Modeling some thermal and physical characteristics of terebinth fruit under semi industrial continuous drying

In this research, the effect of different drying conditions on thermal and physical properties of terebinth fruit was studied. Experiments were conducted with a semi industrial continuous dryer in air temperature levels of 45, 60, 75 °C, air velocity levels of 1, 1.5 and 2 m/s and belt linear speeds of 2.5, 6.5, 10.5 mm/s. Results showed that the Midilli model had the best performance in predicting the moisture ratio. Effective moisture diffusivity of terebinth fruit during experiments was 6.48 × 10^?11–2.34 × 10^?10 m²/s achieved. Activation energy of the samples between 25.45 and 35.16 kJ/mol was obtained. The highest and lowest values of specific energy consumption 65.2 and 10.5 GJ/kg were calculated. Maximum value of shrinkage (16.70 %) was calculated at air temperatures of 75 °C and minimum value (12.34 %) was achieved at air temperature of 45 °C. After drying, total color difference was increased, and hue angle and chroma were decreased. Rupture force for dried terebinth between 80.15 and 112.68 N mm were calculated.