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Accounting for an accurate noise model is essential when dealing with real data, which are noisy due to the effect of environmental noise, failures and limitations in data acquisition and processing. Quantifying the noise model is a challenge for practitioners in formulating an inverse problem, and usually, a simple Gaussian noise model is assumed as a white noise model. Here we propose a pragmatic approach to use an estimated seismic wavelet to capture the correlated noise model (coloured noise) for the processed reflection seismic data. We assess the proposed method through a direct inversion of post‐stack seismic data associated with a carbonate reservoir of an oil field in southwest Iran to porosity, using a probabilistic sampling‐based inversion algorithm. In the probabilistic formulation of the inverse problem, we assume eight different noise models with varying bandwidth and magnitude and investigate the corresponding posterior statistics. The results indicate that if the correlated nature of the noise samples is ignored in the noise covariance matrix, some unrealistic features are generated in porosity realizations. In addition, if the noise magnitude is underestimated, the inversion algorithm overfits the data and generates a biased model with low uncertainty. Furthermore, by considering an imperfect bandwidth for the noise model, the error is propagated to the posterior realizations. Assuming the correlated noise in a probabilistic inversion resolves these issues significantly. Therefore, for inverting real seismic data where the estimation of the magnitude and correlations of the noise is not straightforward, the wavelet, which is estimated from the real seismic data, provides a good proxy for describing the correlation of the noise samples or equivalently the bandwidth of the noise model. In addition, it might be better to overestimate the noise magnitude than to underestimate it. This is true especially for an uncorrelated noise model and to a lesser degree also for the correlated noise model. [ABSTRACT FROM AUTHOR]

In the global COVID-19 epidemic, humans are faced with a new challenge. The concept of quarantine as a preventive measure has changed human activities in all aspects of life. This challenge has led to changes in the environment as well. The air quality index is one of the immediate concrete parameters. In this study, the actual potential of quarantine effects on the air quality index and related variables in Tehran, the capital of Iran, is assessed, where, first, the data on the pollutant reference concentration for all measuring stations in Tehran, from February 19 to April 19, from 2017 to 2020, are monitored and evaluated. This study investigated the hourly concentrations of six particulate matters (PM), including PM2.5, PM10, and air contaminants such as nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), and carbon monoxide (CO). Changes in pollution rate during the study period can be due to reduced urban traffic, small industrial activities, and dust mites of urban and industrial origins. Although pollution has declined in most regions during the COVID-19 quarantine period, the PM2.5 rate has not decreased significantly, which might be of natural origins such as dust. Next, the air quality index for the stations is calculated, and then, the interpolation is made by evaluating the root mean square (RMS) of different models. The local and global Moran index indicates that the changes and the air quality index in the study area are clustered and have a high spatial autocorrelation. The results indicate that although the bad air quality is reduced due to quarantine, major changes are needed in urban management to provide favorable conditions. Contaminants can play a role in transmitting COVID-19 as a carrier of the virus. It is suggested that due to the rise in COVID-19 and temperature in Iran, in future studies, the effect of increased temperature on COVID-19 can be assessed. [ABSTRACT FROM AUTHOR]

Three dimensional epitaxially-fused colloidal quantum dot (QD) superlattices (epi-SLs) feature exceptional electronic coupling and spatial order and are promising systems for studying the emergence of delocalized states and mini-band charge transport in self-assembled solids. However, energy disorder arising from structural defects and aperiodicity has so far resulted in charge carrier localization and slow hopping transport. Detailed 3D structural characterization is critical for rationally improving epi-SL structural perfection to trigger the formation of mini-bands. Here, we analyze the 3D structure of a 120 × 38 nm disc-shaped region of a PbSe QD epi-SL using full-tilt high-angle annular dark-field electron tomography. The high spatial resolution of the tomographic reconstruction (0.65 nm) enables determination of the center-of-mass coordinates of all 1846 QDs in the sample as well as the size and shape of the thousands of epitaxial connections (necks) between the QDs. The tomogram reveals the detailed crystallography and internal positional disorder of the three SL grains that constitute this sample. A map of the neck network is used to quantify relationships between neck number (the number of necks each QD possesses), average neck diameter, QD location in the film, and the nearest neighbor inter-QD distance and distance distribution. We find a strong positive correlation between neck number and local spatial order, suggesting that future improvements in neck connectivity are likely to simultaneously enhance the overall structural perfection of the epi-SLs. A kinetic Monte Carlo model is employed to estimate the electron mobility of the tomography sample and assess the impact of grain boundaries on charge transport. Our electron tomography study establishes a baseline for the quantitative statistical analysis of structural defects in 3D QD epi-SLs. [ABSTRACT FROM AUTHOR]

Herein, influence of coil geometry in a Czochralski crystal growth system is studied using 3D finite element method. Three different geometries for the helical RF‐coil including solenoid, conical solenoid, and rectangular are considered and distribution of magnetic flux density (through the system), produced heat in the RF‐coil and the graphite crucible, as well as heat volume integral are calculated. The obtained numerical results show that every considered coil produces a special heating structure due to its shape with some advantages and disadvantages. [ABSTRACT FROM AUTHOR]

In this paper, a magnetic flux concentrator (MFC) is reported, and its geometry effect on the induction heating process has been calculated in a Czochralski crystal growth system using the 2D finite element method. We have considered 8 cases; for the first case, the system has no magnetic flux concentrator. By solving Maxwell's equations, quantities such as distribution of electromagnetic fields as well as heat and its rate (in coil and crucible) have been computed. The results show that the presence of the magnetic flux concentrator and its different geometries has dramatic effect on the above mentioned parameters. The volumetric heat rate in the crucible bottom significantly increases possibly due to the presence of solidified melt. In addition to the crucible bottom with different MFC forms, the distribution and value of generated heat in the crucible wall change strongly. [ABSTRACT FROM AUTHOR]

The use of fullerene as acceptor limits the thermal stability of organic solar cells at high temperatures as their diffusion inside the donor leads to phase separation via Ostwald ripening. Here it is reported that fullerene diffusion is fully suppressed at temperatures up to 140 °C in bulk heterojunctions based on the benzodithiophene-based polymer (the poly[[4,8-bis[(2-ethylhexyl)oxy]-benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]-thieno[3,4-b]thiophenediyl]], (PTB7) in combination with the fullerene derivative [6,6]-phenyl-C71-butyric acid methyl ester (PC70BM). The blend stability is found independently of the presence of diiodooctane (DIO) used to optimize nanostructuration and in contrast to PTB7 blends using the smaller fullerene derivative PC70BM. The unprecedented thermal stability of PTB7:PC70BM layers is addressed to local minima in the mixing enthalpy of the blend forming stable phases that inhibit fullerene diffusion. Importantly, although the nanoscale morphology of DIO processed blends is thermally stable, corresponding devices show strong performance losses under thermal stress. Only by the use of a high temperature annealing step removing residual DIO from the device, remarkably stable high efficiency solar cells with performance losses less than 10% after a continuous annealing at 140 °C over 3 days are obtained. These results pave the way toward high temperature stable polymer solar cells using fullerene acceptors. [ABSTRACT FROM AUTHOR]

Achievement of long-term stability of organic photovoltaics is currently one of the major topics for this technology to reach maturity. Most of the techniques used to reveal degradation pathways are destructive and/or do not allow for real-time measurements in operating devices. Here, three different, nondestructive techniques able to provide real-time information, namely, film absorbance, capacitance-voltage ( C-V), and impedance spectroscopy (IS), are combined over a period of 1 year using non-accelerated intrinsic degradation conditions. It is discerned between chemical modifications in the active layer, physical processes taking place in the bulk of the blend from those at the active layer/contact interfaces. In particular, it is observed that during the ageing experiment, the main source for device performance degradation is the formation of donor-acceptor charge-transfer complex ( [ABSTRACT FROM AUTHOR]

For making decisions about issues such as the time and number of orders for replenishing bookstores, assessing customer's interests in different regions and reducing maintenance time of books in stock, many decision makers send their queries manually to databases. This is a time consuming process as well as the probability of error in writing the queries. This research addresses the issue of making fast and complex reporting on massive amount of data in bookstores databases. For this purpose a Business Intelligence system has been designed to collect data from information systems in different bookshops and through "Extract, Transform, Load" process stores them to a Data Warehouse. After a report is requested by a user the system automatically generates the query and sends it to the Data Warehouse to display requested report in real-time. Which in comparison with databases, multidimensional reporting is done more quickly. In order to design the Data Warehouse, SQL Server Data Tools is used. It should be mentioned that due to unavailability of thousands of actual data we used SQL Server Data generator to generate unique data. This limitation has decreased somewhat the accuracy of the results. The comprehensive and accurate reports which the system provides help decision makers to adopt precise, timely and effective decisions. [ABSTRACT FROM AUTHOR]

Analyzing the factors affecting customer satisfaction in banking industry and adopting appropriate policies about these factors, is one of the effective ways for attracting customer trust and making them loyal. This research has focused on studying the factors affecting customer satisfaction in traditional and electronic banking industry to recognize which factors lead to customer satisfaction. So, first through the review of literature, some factors have been extracted such as, traditional service quality, electronic service quality, customer satisfaction, customer loyalty and customer trust. Based on these factors structural equation modeling has been formed. The statistical population of the study is the customers of one of the state banks among which 297 people were selected as a sample. The data have been analyzed with the structural equation modeling using AMOS software. The results of the analysis show that the electronic service quality and only two dimensions of traditional service quality including empathy and tangibility affect customer satisfaction. Also, the effect of customer satisfaction on customer trust and loyalty because of government support and old creditably of the bank under study has been confirmed. [ABSTRACT FROM AUTHOR]

Gold-silica hybrids are appealing in different fields of applications like catalysis, sensorics, drug delivery, and biotechnology. In most cases, the morphology and distribution of the heterounits play significant roles in their functional behavior. Methods of synthesizing these hybrids, with variable ordering of the heterounits, are replete; however, a complete characterization in three dimensions could not be achieved yet. A simple route to the synthesis of Au-decorated SiO2 spheres is demonstrated and a study on the 3D ordering of the heterounits by scanning transmission electron microscopy (STEM) tomography is presented-at the final stage, intermediate stages of formation, and after heating the hybrid. The final hybrid evolves from a soft self-assembled structure of Au nanoparticles. The hybrid shows good thermal stability up to 400 °C, beyond which the Au particles start migrating inside the SiO2 matrix. This study provides an insight in the formation mechanism and thermal stability of the structures which are crucial factors for designing and applying such hybrids in fields of catalysis and biotechnology. As the method is general, it can be applied to make similar hybrids based on SiO2 by tuning the reaction chemistry as needed. [ABSTRACT FROM AUTHOR]

Gold-silica hybrids are appealing in different fields of applications like catalysis, sensorics, drug delivery, and biotechnology. In most cases, the morphology and distribution of the heterounits play significant roles in their functional behavior. Methods of synthesizing these hybrids, with variable ordering of the heterounits, are replete; however, a complete characterization in three dimensions could not be achieved yet. A simple route to the synthesis of Au-decorated SiO2 spheres is demonstrated and a study on the 3D ordering of the heterounits by scanning transmission electron microscopy (STEM) tomography is presented-at the final stage, intermediate stages of formation, and after heating the hybrid. The final hybrid evolves from a soft self-assembled structure of Au nanoparticles. The hybrid shows good thermal stability up to 400 °C, beyond which the Au particles start migrating inside the SiO2 matrix. This study provides an insight in the formation mechanism and thermal stability of the structures which are crucial factors for designing and applying such hybrids in fields of catalysis and biotechnology. As the method is general, it can be applied to make similar hybrids based on SiO2 by tuning the reaction chemistry as needed. [ABSTRACT FROM AUTHOR]

Introduction: HBc particles have potential as drug delivery vehicles for cancer therapy. They are hollow nano-particles of 30-34 nm diameter and 7 nm thick envelopes, consisting of 180-240 units of 21 kDa core monomers. They possess the capacity to assemble/disassemble in a controlled manner, allowing encapsidation of various drugs and other biomolecules. Furthermore, other functional motifs, like receptor binding sequences, can be expressed. Objectives: This study focuses on the development of genetically modified HBc particles for in vivo nuclear imaging to specifically target HER- 2-expressing tumours, for future cancer diagnosis and therapy. Materials and Methods: The non-specific binding capacity of wild type HBc particles was reduced by genetic deletion of the sequence encoding argininerich domains. ZHER-2 affibodies were expressed on the HBc particles surface to achieve a specific HER-2-targeting. HIS-tag was introduced at the N-terminal of HBc monomers to allow the radiolabelling of HBc particles with 99mTc. SPECT/CT imaging and quantitative gamma counting were performed to characterise the organ biodistribution profile of the HER-2 specific-targeting HBc particles in tumour-bearing mice. Results: 97.2% and 98.0% radiolabelling efficiency was achieved for ΔHBc and ZHER-2-ΔHBc particles, respectively. 99mTc-ΔHBc and 99mTc-ZHER-2-ΔHBc was purified from free [99mTc(CO)3]+ and exhibited 100% radiolabelling efficiency. Both types of HBc particles exhibited 100% stability in serum and PBS. In vivo studies confirmed positive uptake of ZHER-2- ΔHBc particles in HER-2-expressing tumours, compared to non-targeted ΔHBc particles in intraperitoneal tumourbearing mice models. Conclusion: The present results highlight the potential of these nanocarriers in targeting HER-2-positive metastatic abdominal cancer following intra-peritoneal administration. [ABSTRACT FROM AUTHOR]

The development of a proper processing method for the fabrication TiB2-based wettable cathodes for aluminum electrolysis has been challenging for more than half a century. In this work, TiB2-based ceramics were consolidated via pressureless sintering using Ti, Fe, and Ti-Fe additives. The microstructure, physical and mechanical properties as well as the interaction and the stability of the material in liquid aluminum were investigated. It was shown that specimens sintered with a Ti-Fe additive have excellent stability in liquid aluminum as the solid TiB2 skeleton maintained its integrity and strength after 5 days of exposure in liquid aluminum at 960 °C. Transmission electron microscopy analysis revealed that the formation of inter-particle bridges of pure TiB2 is responsible for the good resistance of the material in molten aluminum. A sintering mechanism was proposed for the consolidation of TiB2 with a Ti-Fe additive. TiB2-based ceramic sintered with a Ti-Fe alloy is suggested as a potentially reliable material for application as wettable cathode for aluminum electrolysis. [ABSTRACT FROM AUTHOR]

The concept of protecting groups, widely used in organic chemistry, has been applied for the synthesis of Au-silica Janus stars, in which gold branches protrude from one half of Au-silica Janus spheres. This configuration opens up new possibilities to apply the plasmonic properties of gold nanostars, as well as a variety of chemical functionalizations on the silica component. [ABSTRACT FROM AUTHOR]

Correction for 'Structural characterization of a polycrystalline epitaxially-fused colloidal quantum dot superlattice by electron tomography' by Xiaolei Chu et al., J. Mater. Chem. A, 2020, DOI: 10.1039/d0ta06704k. [ABSTRACT FROM AUTHOR]