Polyamide 6–Cellulose Composites: Effect of Cellulose Composition on Melt Rheology and Crystallization Behavior

Melt rheology and crystallization behavior of polyamide 6 (PA 6) and microcrystalline cellulose (MCC) composites were systematically studied in this research. The incorporation of MCC into the PA 6 matrix resulted in higher complex viscosities (|η*|), storage modulus (G′), and shear viscosities than those of neat PA 6, especially at low frequencies. The orientation of rigid molecular chains in the composites introduced by the addition of MCC induced a strong shear thinning behavior with an increase in MCC loading. The non‐isothermal crystallization kinetics of PA 6 and MCC composites were investigated by differential scanning calorimetry. The Avrami and Tobin model were applied to describe the process of non‐isothermal crystallization and to determine the crystallization parameters of the composites. Analysis of the crystallization kinetics indicated that the Avrami (n_a) and Tobin exponent (n_t) was altered by the MCC. It was also found that the Avrami and Tobin equations fit the empirical data well. POLYM. ENG. SCI., 54:739–746, 2014. © 2013 Society of Plastics Engineers     

An Overview on SARS‑CoV‑2(COVID‑19)and Other Human Coronaviruses and Their Detection Capability via Amplification Assay,Chemical Sensing,Biosensing,Immunosensing,and Clinical Assays

A novel coronavirus of zoonotic origin(SARSCoV-2)has recently been recognized in patients with acute respiratory disease.COVID-19 causative agent is structurally and genetically similar to SARS and bat SARS-like coronaviruses.The drastic increase in the number of coronavirus and its genome sequence have given us an unprecedented opportunity to perform bioinformatics and genomics analysis on this class of viruses.Clinical tests like PCR and ELISA for rapid detection of this virus are urgently needed for early identification of infected patients.However,these techniques are expensive and not readily available for point-of-care(POC)applications.Currently,lack of any rapid,available,and reliable POC detection method gives rise to the progression of COVID-19 as a horrible global problem.To solve the negative features of clinical investigation,we provide a brief introduction of the general features of coronaviruses and describe various amplification assays,sensing,biosensing,immunosensing,and aptasensing for the determination of various groups of coronaviruses applied as a template for the detection of SARS-CoV-2.All sensing and biosensing techniques developed for the determination of various classes of coronaviruses are useful to recognize the newly immerged coronavirus,i.e.,SARS-CoV-2.Also,the introduction of sensing and biosensing methods sheds light on the way of designing a proper screening system to detect the virus at the early stage of infection to tranquilize the speed and vastity of spreading.Among other approaches investigated among molecular approaches and PCR or recognition of viral diseases,LAMP-based methods and LFAs are of great importance for their numerous benefits,which can be helpful to design a universal platform for detection of future emerging pathogenic viruses.     

Resorcinol formaldehyde xerogels modified with mercapto functional groups as mercury adsorbent

Resorcinol formaldehyde xerogels are modified by mercaptopropyl‐trimethoxysilane during the sol–gel process used to produce the xerogel. The chemical modification is confirmed by Fourier‐transform infrared spectroscopy. The xerogel is then used to adsorb mercury ions from aqueous solutions. The effects of the molar ratios of the precursors as well as the catalyst and the modifier are studied on the textural properties of the xerogel and the adsorption efficiency. It is shown that the chemical modification of the resorcinol formaldehyde xerogels creates the chemical sites on the structure of the xerogel to adsorb more mercury ions and increase the adsorption efficiency. At the same time, chemical modification decreases the xerogel surface area which results in a reduction of the mercury adsorption. Therefore, there exists an optimum value for the chemical modification of the xerogel to achieve the highest adsorption efficiency. Adsorption kinetics as well as equilibrium isotherm of xerogels were examined using pseudo‐first‐ and second‐order kinetic equations, and Freundlich and Langmuir isotherm models. The adsorption kinetics was found to follow the pseudo‐second‐order kinetic equations. The experimental data was also fitted into the Longmuir model more precisely comparing the Freundlich model. Finally, a series of mercury adsorption–desorption tests proved that the optimized mercapto‐modified resorcinol formaldehyde xerogel was an efficient reusable adsorbent for mercury ions. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42543.     

Sensor fusion by pseudo information measure: a mobile robot application

In any autonomous mobile robot, one of the most important issues to be designed and implemented is environment perception. In this paper, a new approach is formulated in order to perform sensory data integration for generation of an occupancy grid map of the environment. This method is an extended version of the Bayesian fusion method for independent sources of information. The performance of the proposed method of fusion and its sensitivity are discussed. Map building simulation for a cylindrical robot with eight ultrasonic sensors and mapping implementation for a Khepera robot have been separately tried in simulation and experimental works. A new neural structure is introduced for conversion of proximity data that are given by Khepera IR sensors to occupancy probabilities. Path planning experiments have also been applied to the resulting maps. For each map, two factors are considered and calculated: the fitness and the augmented occupancy of the map with respect to the ideal map. The length and the least distance to obstacles were the other two factors that were calculated for the routes that are resulted by path planning experiments. Experimental and simulation results show that by using the new fusion formulas, more informative maps of the environment are obtained. By these maps more appropriate routes could be achieved. Actually, there is a tradeoff between the length of the resulting routes and their safety and by choosing the proper fusion function, this tradeoff is suitably tuned for different map building applications.     

Survey on location information services for Vehicular Communication Networks

Vehicular Communication Networks (VCNs) are used to supply a communication platform for Intelligent Transportation Systems services also for value added services in different road systems. In comparison to other communication networks, VCNs come with major challenges: high mobility and velocity of vehicles that cause rapidly change topology of network and fast change of vehicle’s locations. Location information services (LISs) or location management systems (LMSs) are used to provide location information about vehicles such as current location, speed, direction and report this information to other vehicles or network entities that require this information. We present a survey for LISs in VCNs and introduce 11 approaches in literature. Moreover, we present a classification for LISs and compare mentioned approaches based on our classification. Finally we evaluate studied LISs by some performance properties to measure their overall efficiency.     

Significant improvement of semi-solid microstructure and mechanical properties of A356 alloy by ARB process

Accumulative roll bonding (ARB) process was used in this study as an effective method for manufacturing high-strength, finely-dispersed and highly-uniform A356 alloy. It was found that when the number of ARB cycles was increased, the uniformity of silicon particles in the aluminum matrix improved, the particles became finer and spheroider and therefore, the tensile strength (TS) and ductility of the samples improved. The microstructure of the manufactured A356 alloy after five ARB cycles indicated a totally modified structure such that it's TS and elongation values reached 269 MPa and 5.3% which were 2.6 and 2.5 times greater than those of the as-cast material, respectively. Also, the hardness value increased from 55.4 (for as-cast sample) to 100.2 HV (after the fifth cycle of ARB), and registered 81% increase.     

Formulation of dynamics,actuation, and inversion of a three‐dimensional two‐link rigid body system

In this paper, three issues related to three‐dimensional multilink rigid body systems are considered: dynamics, actuation, and inversion. Based on the Newton‐Euler equations, a state space formulation of the dynamics is discussed that renders itself to inclusion of actuators, and allows systematic ways of stabilization and construction of inverse systems. The development here is relevant to robotic systems, biological modeling, humanoid studies, and collaborating man‐machine systems. The recursive dynamic formulation involves a method for sequential measurement and estimation of joint forces and couples for an open chain system. The sequence can start from top downwards or from the ground upwards. Three‐dimensional actuators that produce couples at the joints are included in the dynamics. Inverse methods that allow estimation of these couples from the kinematic trajectories and physical parameters of the system are developed. The formulation and derivations are carried out for a two‐link system. Digital computer simulations of a two‐rigid body system are presented to demonstrate the feasibility and effectiveness of the methods. © 2005 Wiley Periodicals, Inc.     

Penetration Depth in Nanoparticles Incorporated Radiofrequency Hyperthermia into the Tissue: Comprehensive Study with Histology and Pathology Observations

In present study, the effective penetration of radiofrequency (RF) induced gold decorated iron oxide nanoparticles (GS@IONPs) hyperthermia was investigated. The effective penetration depth of RF also the damage potency of hyperthermia was evaluated during histopathology observations which were done on the chicken breast tissue and hepatocellular carcinoma (HCC) models. The thermal damages are well‐ documented in our previous cellular study which was engaged with potency of RF hyperthermia in Epithelial adenocarcinoma (MCF‐7) and fibroblast (L‐929) cells deaths [1]. In recent work, PEGylated iron oxide nanoparticles (IONPs) were used as base platform for gold magnetic nanoparticles (GS@IONPs) formation. The 144.00015 MHz, 180W RF generator was applied for stimulating the nanoparticles. The chicken breast tissue and the hepatocellular tumor model was considered in the experimental section. In histology studies, the structural changes also the effective penetration depth of RF induced nanoparticles was observed through microscopic monitoring of the tissue slices in histology observations (Gazi medical school). The highest damage level was seen in 8.0 µm tissue slices where lower damages were seen in depth of 1.0 cm and more inside tissue. The histology observations clarified the effective penetration depth of RF waves and irreversible damages in the 2.0 cm inside the tissue.Inspec keywords: nanomedicine, tumours, biomedical materials, cellular biophysics, nanoparticles, gold, cancer, hyperthermia, magnetic particles, iron compounds, radiation therapyOther keywords: Au‐Fe₃ O₄ , depth 1.0 cm, depth 8.0 mum, power 180.0 W, size 2.0 cm, frequency 144.00015 MHz, microscopic monitoring, structural changes, hepatocellular tumour model, standing wave ratio, propylene glycol, thermal damages, hepatocellular carcinoma models, radiofrequency hyperthermia, nanoparticle dispersion, tissue alterations, modified tissues, gold shell magnetic nanoparticles, chicken breast tissue, gold‐coated iron oxide nanoparticles, pathology observations, effective penetration depth, histology observations, tissue slices     

The influence of different single dietary sources on moult induction in laying hens

An investigation was carried out to assess the possibility of using single dietary sources as alternatives to feed deprivation for the induction of moult in commercial laying hens. The study involved six dietary groups of 29 laying hens: unmoulted, dried tomato pomace, alfalfa meal, rice bran, cumin seed meal and feed withdrawal. The birds received the above diets during the moulting period (11 days), and body weight loss and ovary weight regression were measured. Post‐moult production parameters (number of eggs produced per hen per day, egg weight, shell weight, yolk colour and Haugh unit) were measured for 12 weeks. Results showed that all dietary sources were as effective as feed withdrawal in causing ovary weight regression in birds. Birds provided with tomato pomace or alfalfa showed lower weight losses than feed‐deprived birds at the end of the moulting period. Hens moulted by tomato pomace or alfalfa exhibited post‐moult levels of egg production over a 12 week period that were superior to those of hens moulted by feed withdrawal. Post‐moult eggs laid by hens moulted by all dietary sources were of comparable quality to eggs from feed‐deprived hens and superior to those from unmoulted hens. As fibrous feeds with low metabolisable energy and an appreciable amount of protein, dried tomato pomace and alfalfa meal may be fed to hens on an ad libitum basis for effective moult induction while reducing the stress of severe starvation and retaining comparable egg quality and production. Copyright © 2007 Society of Chemical Industry