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The structures and properties of circumtrindene derivatives were studied at M062X/6-31+G(d,p) level of theory. The UV spectra of compounds were simulated by TD DFT methods. The calculated values of λmax (344 nm to 403 nm) were attributed to HOMO to LUMO electronic transitions of compounds. The frontier molecular orbitals have been studied based on NBO calculations and the results were used to estimate the HOMO—LUMO energy gap, ionization potential, electron affinity, electronegativity, electrophilicity index, global hardness, softness, and chemical potential of the compounds. Among the studied derivatives, the structure containing pyridine and furan rings possessed the highest ionization energy (9.007 eV), electron affinity (2.667 eV), electronegativity (5.837 eV), and was the most polar molecule. In addition, compound 7 had the smallest chemical potential (–5.837 eV), polarizability (328.560 a.u.) and the lowest energy levels of HOMO (–8.3672 eV) and LUMO (–3.3062 eV) orbitals. While the derivative having pyrrole rings had the highest softness (0.172 e/V), chemical potential (–4.272 eV), and the greatest λmax (403 nm) in the UV spectrum. In addition, this compound had the lowest hardness (2.912 eV), ionization energy (7.184 eV) and electronegativity (4.272 eV). Also, the aromaticity of individual rings was evaluated by calculating NICS and HOMHED indices. The NICS results showed that the peripheral 6-membered rings represented the best aromatic properties.

The development of polymer-based composites with thermal transport capability has now become essential in response to the efficient thermal management required in electronic and energy conversion devices. In this work, a novel hybrid filler consisting of graphene nanoplatelet (GNP) and boron nitride microparticles (micro-BN) is used to improve the thermal conductivity of epoxy composite. The GNPs with an average lateral size of 8 µm and an average thickness of 5 nm are in the same volume range with the 1 µm size micro-BN particles. According to the results, the thermal conductivity of the composites changes abruptly with increasing micro-BN loading at fixed GNP loading, which is attributed to the formation of a percolative network through the composite. By using 20% vol. hybrid filler, the thermal conductivity of epoxy increases from 0.22 to 5.64 W/m K, which is 147% higher than the thermal conductivity of GNP composite due to the synergistic effect. Finally, as a secondary filler in the GNP epoxy composite, nano-BN is compared with the micro-BN. It is observed that for thermal conductivity enhancement, the addition of nano-BN is not as effective as micro-BN. On the other sides, unlike nano-BN, by adding of micro-BN, the electrical conductivity of GNP epoxy composite does not change significantly. It is found that for the size of the GNPs used here, 1 µm size of micro-BN is an optimized value that leads to the formation of a strong percolated network of fillers through the composite.

The automation of map generalisation in this study involves an expert system approach that consists of four main components including knowledge acquisition, an inference engine, knowledge representation and a user interface. The acquired knowledge was then utilised to build a knowledge-based solution: a ‘Generalisation Expert System’ (GES) developed in Java, Python and C programming environments for the delivery of generalised geographical features. Its capabilities are demonstrated in a case study through generalising several line and polyline databases over the study area in Canberra, Australia. The cartographic and GIS software communities will benefit from this study through access to a set of tools, guidelines and protocols that incorporate a standardised cartographic generalisation methodology. The results of the trials utilising GES were analysed: a series of generalisation routines were performed to assess the quality of simplification results for different spatial layers. Cartometric measures such as the total length and number of line or polyline segments were used as indices of generalisation to quantify generalisation performance for the target small scale. For example, there are 101,228 segments in 1:250,000 scale and 9,491 segments in 1:500,000 scale contours over the study area. This requires a reduction in the complexity and the density of elevation data. Changes in the representation of contour features at 1:250,000 and 1:500,000 scales as a result of generalisation were quantified. Outputs from map derivation have been analysed applying the Radical Law, this determines the retained number of objects for a given scale change and the number of objects of the original source map. Testing demonstrated that the implemented algorithms in GES are able to extract characteristic vertices on the original entity lines and polylines (e.g. for roads) while excluding non-characteristic lines and polylines to reduce irrelevant computation. This study has demonstrated reasonable improvements in Vertex Reduction, Classification and Merge, Enhanced Douglas-Peucker and Douglas-Peucker-Peschier algorithms. The test results show that GES generalises line features accurately while still maintaining their geometric relations. Existing generalisation software requires advanced technical skills from users; GES however, has a basic and user friendly Graphical User Interface (GUI) which is an advantage to users with basic technical skills and understanding of spatial data management. Changes to geographic parameters should be updated in multi-scale maps and spatial databases in near real-time. GES can be developed as a potential tool for generalising large-scale maps into smaller scales, and creating maps of different themes across a variety of scales. Test results have also demonstrated that the methodology developed improves the efficiency of line and polyline generalisation. This study aims to contribute to generalisation system design and the production of a clear framework for users. Experiments presented in this book can be applied to real world problems such as the generalisation of road networks and area features using GES. Future research should be directed towards developing web mapping platforms with generalisation functionality at varying scales.

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Lateritic gravel is used for road building in Western Australia, with about 8 million m3 required annually. The introduced, soil-borne pathogen Phytophthora cinnamomi, which is associated with mortality of native plants, has been widely spread by using gravel from infested pits. Uninfested gravel is in demand, and in short supply. The biocide metham sodium is registered by the Australian Pesticides and Veterinary Medicine Authority (APVMA) as a soil fumigant, but the registered application method is unsuitable for treating gravel. In moist soil metham sodium decomposes into the fumigant-like pesticide, methyl isothiocyanate (MITC). Field experiments in which metham sodium was applied during the construction of 4 m3 gravel stockpiles, showed Phytophthora spp. are killed within 2 weeks of treatment with 80 mL m3–1 metham sodium. MITC is sealed within the stockpile by surface crusting; it was only detected 5 m downwind within the first 24 h of treatment. It was not detected in gravel 28 days after treatment. This application method that can safely eliminate Phytophthora spp. from infested gravel has been registered by the APVMA, allowing scaling-up trials to be considered.

In this article, the authors illustrate the use of Bloomberg for analyzing topics in macroeconomics and monetary policy in economics and finance courses. The hands-on experience that students gain from such a course has many benefits, including deeper learning and clearer understanding of data. The authors describe goals and learning objectives, then compare Bloomberg with Federal Reserve Economic Data (FRED). In addition, they provide examples of how to use Bloomberg in the classroom, describe how to have students perform sector analysis, show how Bloomberg tools are useful for analyzing monetary policy, discuss how to use Bloomberg to analyze the financial sector, and illustrate the platform’s use in a case study.

The effect of neat and modified nanodiamond (ND) nanoparticles on the structure and performance of PVDF membranes was studied. ND was first oxidized (O-ND) thermally, then silanized (S-ND) using the esterification reaction by vinyltrimethoxysilane, and finally was PVP functionalized (P-ND) via surface initiated free-radical polymerization method. The results of FTIR analysis revealed that PVP was successfully immobilized onto ND nanoparticles. Different percentages of ND and P-ND nanoparticles were then embedded into PVDF membranes. The results showed that the hydriphilicity and water flux of membranes improved as the percentage of nanoparticles increased. Moreover, the number of pores on the surface of PVDF/P-ND membrane increased in comparison to neat PVDF and PVDF/ND membranes even though the pore size distribution curve of PVDF/P-ND membrane was shifted towards smaller pores. In addition, the presence of ND and P-ND nanoparticles within PVDF membranes increased the portion of β–phase in the PVDF structure which resulted in abrasion and fouling resistant membranes. The performance of neat PVDF, 1.5 wt. % PVDF/ND and 1.5 wt. % PVDF/P-ND membranes was studied in MBR system with pharmaceutical wastewater feed and it was found that antifouling properties PVDF/P-ND membrane were better than that of PVDF/ND membrane.

Background : Migraine headache without aura is the most common type of migraine especially among pediatric patients. It has always been a great challenge of migraine diagnosis using quantitative electroencephalography measurements through feature classification. It has been proven that different feature extraction and classification methods vary in terms of performance regarding detection and diagnostic accuracy. Previous work on the subject was controversial, hence a comparison of these methods seems necessary. Objectives : The aim of this research is to compare two parametric and non-parametric feature extraction methods and also two classification methods in order to obtain optimal combinations of diagnostic accuracy. Materials and Methods : Having recorded background EEG from 24 pediatric migraineurs and 19 control subjects, data was processed by Welch’s and Yule-Walker’s methods. Features were selected using genetic algorithm, and then given to a support vector machine and the linear discriminant analysis for the classification. Accuracy was calculated for all combinations having the dominant frequency and the correlated absolute power of each EEG wave band (theta, alpha, and beta) and for all wave bands combined. Results : The highest migraine detection accuracy of 93% was obtained utilizing Welch’s method for EEG feature extraction alongside support vector machine for a classifier. Besides, Yule-Walker autoregressive method showed better performance than Welch’s, when only power bands (and not the dominant frequency) were used as classification input. Conclusion : The superiority of Welch’s method over Yule-Walker’s and the support vector machine over linear discriminant analysis can be great help for further researches on computer aided EEG-based diagnosis of migraine.

A new microscale filtration technique was developed to perform high-throughput (HT) studies of filtration performance by integrating a multi-channel microfluidic flow control (MMFC) system that can...

In this study, the dispersion phenomenon in a poly-dispersed gas-solid confined swirling jet is investigated numerically using an Eulerian–Lagrangian framework. Three continuous random walk models, including Sommerfeld’s model, Moissette et al. (MOB) model, and probability density function (PDF), and the conventionally used eddy life time (ELT) model are incorporated and compared. The results manifest that the important features of the flow, such as the penetration of the medium-sized particles into the corner recirculation zone and the distribution of the light particles downstream of the internal recirculation zone, can only be captured by a proper dispersion modeling even in an unsteady URANS approach resolving the precessing vortex core. Moreover, the ELT model has the largest errors for all particle statistics, especially for the fluctuating velocities (about 60% in average) while other models, especially MOB and PDF, bring about a satisfactory agreement with the experiment. MOB is the most accurate model in predicting the cross-stream particle velocity fluctuations with less than 20% error. Finally, for such a complex practical flow, the spatial decay of concentration profile is a key factor which is much more sensitive to the choice of dispersion model than the mean and fluctuating velocities.

Density wave oscillations and pressure drop oscillations are investigated numerically in two horizontal parallel channels using lumped parameter model assuming a homogeneous two-phase flow model. In this study the effects of external parameters, such as fluid inertia and compressible gases on the stability margins and transient behaviors of parallel channels system are analyzed. The results show, that the fluid inertia and compressible gases have high impact on the stability margins of two parallel channels; in fact, increasing the inlet inertia and outlet compressibility will increase the system stability while increasing the outlet inertia and inlet compressibility decrease its stability.

Membrane filtration is a key separations technique in downstream bioprocessing applications: for a commercial bioprocess operation, 10–20 membrane-related steps are typically required. At the laboratory scale, the evaluation of membrane separation performance often involves a ‘stirred cell device’; however, this simple tool is poorly suited for conducting high-throughput studies of separation performance. Here, we designed a high-throughput stirred cell (HTSC) device which is ideally suited for conducting optimization studies, especially at the early stages of bioprocess development when small volumes of feed material are available. The HTSC allows for up to six filtration experiments to be run simultaneously with continuous mixing above each membrane facilitated by suspended magnetic stir elements. Using fluorescently-labeled dextrans as model biomolecules and commercial ultrafiltration membranes, it was shown that the HTSC device gave the same separation performance as a traditional stirred cell, but with the added benefits of operating at a faster pace (due to its parallel nature) and requiring nearly an order of magnitude lower sample volumes. Furthermore, the utility of the HTSC was demonstrated by concurrently evaluating the performance of four different ultrafiltration membranes for the same model biomolecule and the membrane selectivity for a mixture of two model bio-macromolecules.

Limitation of resources and interest in having economical designs lead to consider nonlinear behavior of materials in analysis and design of structures. During the last decade, the isogeometric analysis (IGA) is proposed and applied to achieve nonlinear analysis of various types of structures. Exact modeling of geometry and high accuracy in approximating unknown displacement field are amongst the advantages of this method. In this research, beside developing isogeometric elasto-plastic analysis formulation by considering von Mises criterion, a comparative study is achieved to investigate effects of using different modeling parameters such as number of control points and different knot spans. A convergence study is also achieved by increasing the number of discretizing control points throughout the domain. In addition, effect of strain hardening parameter is investigated when the isogeometric analysis is used. To demonstrate the accuracy of the method, the results are compared with analytical solutions as well as the finite element method (FEM). To achieve this, several numerical examples are presented.

The use of hybrid filler is a promising strategy for development of thermally conductive polymer composites. This paper reported the measurement of thermal conductivity of the epoxy composite filled with a hybrid filler of graphene nanoplatelet (GNP) and silicon carbide (SiC) microparticles. For this hybrid filler, the effect of the average size of SiC on composite thermal conductivity was examined. The results showed that the thermal synergistic effect was highly affected by the average size of the SiC. By using a hybrid filler of 11% vol. GNP and 9% vol. 1 µm-size SiC micro-particles thermal conductivity has reached 3.44 W m−1 K−1. This value is 42% higher than the thermal conductivity of pure GNP composite at the same total filler loading. Moreover, additional experimental and theoretical analyses were performed to more explicitly understand the mechanism of thermal synergistic effect. It was shown that the synergistic effect between GNP and SiC is attributed to the more effective formation of thermally conductive pathways through the composite. Our results elucidate the mechanism of the thermal synergistic effect and providing information on hybrid filler design to achieve further improvement in the thermal conductivity of polymer composites.

Mixing different species to produce a homogeneous solution is of great interest, affecting the performance of lab-on-a-Chip (LOC) devices. Because of the laminar characteristic of the flow field in microchannels, the LOC devices usually suffer from poor mixing efficiency. This study numerically investigates the enhancement of mixing efficiency in a microchannel using a conductive micro-particle. For this, the governing equations of the induced-charged electrokinetics based on the thin EDL assumption are solved by the finite volume method to provide a comprehensive parametric study on the mixing process and its efficiency taking into account the physical parameters such as the particle size, applied electric field, electric potential and branching inlet.

In this study, a mathematical model is developed to study Pressure drop oscillations (PDOs) in two horizontal parallel channels using lumped parameter model assuming a homogeneous two-phase flow model. This model investigates the effect of external parameters, such as fluid inertia and compressible gases, on the stability margins of PDOs. Results show that the fluid inertia and compressible gases have high impact on the stability margins of two parallel channels; in fact, increasing the inlet inertia and outlet compressibility increases system stability, while increasing the outlet inertia and inlet compressibility decreases system stability. Thus, increasing the sub-cooling number and inlet resistance coefficient improves stability behavior.

Hollow-fiber (HF) membranes are an ideal format for environmental applications and yet the fouling of HF membranes is a complex and ongoing challenge in the field of water and wastewater treatment. There is growing interest in the use of high-throughput (HT) techniques to accelerate the optimization of membrane-based separations. However, all of the previous works in this area have focused on employing HT techniques for flat sheet membranes. In this study, we have developed the first ever high-throughput hollow fiber (HT-HF) membrane device that can run multiple filtration tests in parallel with each test using a single HF membrane to minimize the hold-up volume. The effects of humic acid (HA) type, HA concentration, aqueous solution conditions, filtrate flux, and backwashing conditions on the constant flux filtration performance of polyvinylidene fluoride HF membranes were studied by comparing sieving coefficient results, transmembrane pressure profiles, and changes in hydraulic permeability. In total, over 60 individual filtration experiments and 190 hydraulic permeability measurements, were performed in this comprehensive study. The technique described in this work allows for an efficient way to screen the performance of HF membranes for various applications.

In this research, a theoretical model is presented to investigate the density wave oscillations (DWOs), in two horizontal parallel channels with lumped parameter model based on two phase homogeneous hypothesis. The parallel channel is composed of the entrance section, heating section and outlet section and the model consists of the boiling channel model, pressure drop model, parallel channel model, constructive model and inertia and compressibility effects, while subcooled boiling effect is neglected and the governing equations are solved by Gear method. The model is validated with experimental data of a single channel flow instability experiment. Then the flow instability in twin channel system is studied under different conditions. This model can analyze the effects of external parameters, such as fluid inertia and compressible gases on the stability margins of density wave oscillations. The results show that, the fluid inertia and compressible gases can significantly change the stability margins of two parallel channels; in fact, the stability behavior of two parallel channel system improves with increasing the inlet inertia and outlet compressibility but, increasing the outlet inertia and inlet compressibility have negative effects the system stability.

Background and aim: Adverse effects inner anger and interpersonal relationships will follow on from the other parent behavior management training and promoting and improving relations between parent-child.در این راستا هدف پژوهش حاضر بررسی اثربخشی آموزش مدیریت رفتار براساس مدل بارکلی در کاهش خشم دانش آموزان دختر و پسر قلدر دوره اول متوسطه بود. Methods: The present Experimental research used a pretest– posttest and a control group. جامعه آماری شامل دانش آموزان دختر و پسر دوره اول متوسطه شهر تبریز که در سال تحصیلی 93-1392 مشغول به تحصیل بودند. The population consisted of male and female junior high school students in Tabriz who were enrolled in the 2012-2013 school year. به منظور اجرای پژوهش پس از انجام سرند توسط معلمان و اجرای پرسشنامه قلدر/قربانی الویوس، 30نفر از کودکانی که براساس نمرات کسب شده در پرسشنامه الویوس، به عنوان قلدر طبقه بندی شده بودند به صورت تصادفی در دو گروه 15 نفری آزمایش و کنترل جایگزین شدند؛ و پس از تکمیل پرسشنامه خشم نیلسون(2000) توسط دانش آموزان قلدر؛ والدین گروه آزمایش به مدت 9جلسه (45 دقیقه ای) در برنامه آموزش مدیریت رفتار قرارگرفتند، ولی گروه کنترل هیچگونه آموزشی دریافت نکرد.Therefore, after screening by the teachers and the Nelson anger questionnaire, 30 children who, according to scores on the questionnaire were bullies, were classified randomly into two groups of 15 cases and controls were replaced and after completing the questionnaire anger Nilsson (2000) bullying by students, parents groups for 9 sessions (45 minutes each) were treated in a management training program, while the control group received no training. آزمودنی ها پس پایان جلسات آموزش مدیریت رفتار والدین ، مورد بررسی مجدد قرار گرفتند. Parent Management Training participants after the end of the session, were reviewed and followed a month later. داده ها با استفاده از نرم افزار آماری18 SPSS و با استفاده از شاخص های توصیفی و آزمون تحلیل کوواریانس چند متغیری مورد تجزیه وتحلیل قرار گرفتند. نتایج حاکی از اثربخشی آموزش مدیریت رفتاری والدین بر کاهش خشم نوجوانان قلدر (05/0 P< ) بود. Data were analyzed by the SPSS version 18 statistical software using descriptive indicators and multivariate analysis. Results: The results indicated the effectiveness of Parent Management Training to Reduce Anger of the teen bullies (P

A new micro-pump based on the electrokinetic phenomenon is numerically studied using a conducting circular obstacle placed in a junction of three micro-channels. The induced-charge electrokinetic flow over the conducting obstacle generates vortices and provides a pressure gradient, resulting in pumping the solution towards the micro-pump outlet. A theoretical model based on the thin electric double layer (EDL) is developed to simulate the influence of the applied electric field on the flow field. The numerical results indicate that the induced pressure and the mass flow rate in the pump outlet are affected by the electric field magnitude, micro-channel walls zeta potential, circular obstacle size and its position.

An effective approach for increasing the life cycle of poly ortho aminophenol (POAP) as a p-type conductive polymers is combining conventional conductive polymers and nanomaterials to fabricate hybrid electrodes. In this paper, functionalized graphene oxide (FGO) has first been synthesized using a chemical approach. Hybrid POAP/FGO films have then been fabricated by POAP electropolymerization in the presence of FGO nanoparticles as active electrodes for electrochemical supercapacitors. Based on the atomic scale study results, it seems that H3PO4(-) oxygen atoms and terminal pyridine ring nitrogen atoms play a crucial role in the intramolecular charge and energy transfer in the FGO molecular systems. Theoretical studies, surface and electrochemical analyses have been used for characterization of POAP/FGO composite films. Different electrochemical methods including galvanostatic charge discharge experiments, cyclic voltammetry and electrochemical impedance spectroscopy have been applied to study the system performance. This work introduces new nanocomposite materials for electrochemical redox capacitors with such advantages as the ease of synthesis, high active surface area and stability in an aqueous electrolyte.

LOFAR is the LOw-Frequency Radio interferometer ARray located at midlatitude (52°53′N). Here we present results on ionospheric structures derived from 29 LOFAR nighttime observations during the winters of 2012/2013 and 2013/2014. We show that LOFAR is able to determine differential ionospheric total electron content values with an accuracy better than 0.001 total electron content unit = 1016m−2 over distances ranging between 1 and 100 km. For all observations the power law behavior of the phase structure function is confirmed over a long range of baseline lengths, between 1 and 80 km, with a slope that is, in general, larger than the 5/3 expected for pure Kolmogorov turbulence. The measured average slope is 1.89 with a one standard deviation spread of 0.1. The diffractive scale, i.e., the length scale where the phase variance is 1rad2, is shown to be an easily obtained single number that represents the ionospheric quality of a radio interferometric observation. A small diffractive scale is equivalent to high phase variability over the field of view as well as a short time coherence of the signal, which limits calibration and imaging quality. For the studied observations the diffractive scales at 150 MHz vary between 3.5 and 30 km. A diffractive scale above 5 km, pertinent to about 90% of the observations, is considered sufficient for the high dynamic range imaging needed for the LOFAR epoch of reionization project. For most nights the ionospheric irregularities were anisotropic, with the structures being aligned with the Earth magnetic field in about 60% of the observations.