Toughening of epoxy resin systems using core–shell rubber particles: a literature review

Journal of Materials Science - Excellent thermal and mechanical properties and high chemical resistance with low shrinkage of epoxy resins open a wide window of various industrial applications,...     

One‐step solvothermal synthesis of hollow Bi2WO6 photocatalyst

A one‐step solvothermal synthesis of hollow microspherical Bi₂WO₆ nanophotocatalyst was carried out for the first time under the collective action of potassium chloride (KCl) and polyvinylpyrrolidone (PVP). The physicochemical properties such as crystal structure, morphology, specific surface area, and optical properties of the material were characterized by means of XRD, SEM, EDS, UV‐vis, and BET. The effect of KCl and PVP on the morphology control of the product is discussed. Rhodamine B dye in wastewater was used as model pollutant, and the effect of hollow microspherical morphology on photocatalytic activity is discussed. The results presented here provide a simple, effective, and widely applicable approach for the rapid synthesis of special morphology Bi₂WO₆ by a one‐step method.     

Nucleation Rate Prediction of Curcumin Particles in Microfluidic‐Assisted Nanoprecipitation

A hybrid computational model was developed to interpret the formation of curcumin particles via liquid antisolvent precipitation (LASP) in three microchannel reactors (MCRs) with different confluence angles. The computational fluid dynamics (CFD) model was numerically combined with a discretized population balance approach. The nucleation kinetics were computed using an expression obtained from the nucleation rate and supersaturation equation from previous experimental data. A quantitative comparison of the particle size distributions (PSDs) demonstrated that the particles with the smallest diameters are observed right after the intersection of the three streams. Besides, the large confluence angle of 135° in the MCR presented higher population density as a result of the smaller size of the precipitated curcumin particles. These findings illustrate the efficient applicability of the hybrid model.     

Polyionene/Br3 Grafted on Magnetic Nanoparticles as an Efficient and Eco-Friendly Catalyst for the Metal Free Synthesis of 3,4-Dihydropyrimidin-2(1H)-Ones/Thiones

Silicon - A novel polyionene modified magnetic nanoparticle with a core-shell-shell structure was developed for utilization as a heterogeneous catalyst in the metal free synthesis of...     

Modified covariance intersection for data fusion in distributed nonhomogeneous monitoring systems network

Monitoring networks contain monitoring nodes that observe an area of interest to detect any possible existing object and estimate its states. Each node has characteristics such as probability of detection and clutter density that may have different values for distinct nodes in nonhomogeneous monitoring networks. This paper proposes a modified covariance intersection method for data fusion in such networks. It is derived by formulating a mixed game model between neighbor monitoring nodes as players and considering the inverse of the trace of fused covariance matrix as players' utility function. Monitoring nodes estimate the states of any possible existing object by applying joint target detection and tracking filter on their own observations. Processing nodes fuse the estimated states received from neighbor monitoring nodes by the proposed modified covariance intersection. It is validated by simulating target detection and tracking problem in 2 situations: 1 target and unknown number of targets.     

Salicylic acid nanoparticles (SANPs) improve growth and phytoremediation efficiency of Isatis cappadocica Desv., under As stress

Arsenic (As) is a toxic metalloid dispersed in the environment and it cause serious toxicity to plants. Salicylic acid (SA) plays an important role in many plant growth processes involved in plant defence against heavy metal or metalloid stress. In the present study, for the first time, chitosan nanoparticles was synthesised, loaded by SA and the positive role of SA on growth and phytoremediation efficiency of Isatis cappadocica against As toxicity were evaluated. The highest arsenate treatment (1200 µM) caused a decrease in plant biomass that, however, its combined application with salicylic acid nanoparticles (SANPs) substantially increase in shoot height, root length and their biomass production compared with As stressed plants. The pretreatment of SANPs by increasing arsenate supply, simultaneously increased the As concentration in roots and shoots of I. cappadocica which reached a maximum of 705 and 1188 mg/kg, respectively. This results suggest that high levels of As stress induce stress status in I. cappadocica which SANPs pretreatment application limit these toxic effects of As. Therefore, SANPs has a significant beneficial effect on the growth and phytoremediation efficiency of I. cappadocica subjected to As stress.Inspec keywords: nanoparticles, nanobiotechnology, botany, toxicology, arsenic, biological techniques, polymersOther keywords: salicylic acid nanoparticles, SANP, plant growth efficiency, phytoremediation efficiency, Isatis cappadocica Desv, arsenic stress, toxic metalloid, plant toxicity, plant defence, metalloid stress, chitosan nanoparticles, plant biomass, shoot height, root length, biomass production, I. cappadocica, As     

FT-PDC: an enhanced hybrid congestion-aware fault-tolerant routing technique based on path diversity for 3D NoC

In recent years, using three-dimensional Network-on-Chip (3D-NoC) has increased due to its high performance and integration of processing elements. However, as technology evolves, dimension of processing elements and the number of connections are decreasing and this increases their sensitivity to external factors. Therefore, fault detection is one of the most important challenges of designing 3D-NoC because even a transistor not working well may cause the whole system not to work. Many methods have been provided so far to make three-dimensional NoC tolerant against fault, but most of these methods suffer from some disadvantages. For example, their fault detection models are not strong enough or they do not consider the network traffic. Regarding these problems, in this article, a routing technique called fault-tolerant routing algorithm based on path diversity and congestion (FT-PDC) for three-dimensional mesh connectivity based on NoC is provided that has some features like finding the shortest current path, considering fault in vertical and horizontal links, and considering path diversity and congestion. In addition to these features, FT-PDC could solve the problems of other methods to a great extent considering network traffic conditions and sending the packet from a path in which traffic conditions are two hops better than the other paths. These features have led to the superiority of the proposed method over other methods. The simulation results in the Noxim simulator show that latency and throughput of FT-PDC compared to similar recent methods have significantly improved.

     

Query optimization mechanisms in the cloud environments: A systematic study

The goal of a query optimizer is to provide an optimal Query Execution Plan (QEP) by comparing alternative query plans. In a distributed database system over cloud environment, the relations required by a query plan may be stored at multiple sites. This leads to an exponential increase in the number of possible equivalent plan alternatives to find an optimal QEP. Although it is not computationally reasonable to explore exhaustively all possible plans in such large search space. Although query optimization mechanisms are important in the cloud environments, to the best of our knowledge, there exists no complete and systematic review on investigating these issues. Therefore, in this paper, four categories to study these mechanisms are considered which are search‐based, machine learning‐based, schema‐based, and security‐based mechanisms. Also, this paper represents the advantages and disadvantages of the selected query optimization techniques and investigates the metrics of their techniques. Finally, the important challenges of these techniques are reviewed to develop more efficient query optimization techniques in the future.