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In order to determine the pollutants concentration emitted by point stationary sources (stacks), the effective height of the emission must be known. Among the formulas presented in the literature for the calculation of the plume rise, Briggs equations are the most used. In this study Brigs method is used to estimate plume rise above a stationary point source (stack) considering the influence of climatic factors (wind speed and atmospheric air temperature) and effluent characteristics (temperature and velocity at stack exit). Results are presented for neutral atmospheric stability class depending on distance from the stack. This study presents an analysis of air dispersion of a gaseous effluent emitted through a stack having a height of 220 m and 4 m in diameter. The maximum height at which plume centerline rises above stack is estimated using Briggs equations. Also, is considered the influence of several factors which are given further. All estimations are presented for neutral atmospheric stability class in function of the distance from the point source up to 3000 meters, at 500 m intervals. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of Nanjing University of Aeronautics & Astronautics is the property of Editorial Department of Journal of Nanjing University of Aeronautics & Astronautics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Soybean MON 87705 × MON 87708 × MON 89788 (three‐event stack soybean) was produced by conventional crossing to combine three single soybean events: MON 87705, MON 87708 and MON 89788. This combination is intended to alter the fatty acid profile in the seed (in particular increasing the levels of oleic acid) and tolerance to glyphosate‐based and dicamba herbicides. The Genetically Modified Organisms Panel previously assessed the three single soybean events and did not identify safety concerns. No new data on the single soybean events, leading to modification of the original conclusions on their safety have been identified. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicate that the combination of the single soybean events and of the newly expressed proteins in the three‐event stack soybean does not give rise to food and feed safety and nutritional concerns. In the case of accidental release of viable three‐event stack soybean seeds into the environment, this would not raise environmental safety concerns. The post‐market environmental monitoring plan and the reporting intervals are in line with the intended uses of soybean MON 87705 × MON 87708 × MON 89788. Considering the altered fatty acid profile of the three‐event stack soybean, a proposal for post‐market monitoring needs to be provided by the applicant. The GMO Panel notes that in the context of this application EFSA‐GMO‐NL‐2015‐126 the applicant did not provide a 90‐day study on MON 87705 soybean in line with the applicable legal requirements. Therefore, the GMO Panel is not in the position to finalise the risk assessment of soybean MON 87705 × MON 87708 × MON 89788 under the current regulatory frame.

This work aims to study the influence of cutting parameters (cutting speed, feed rate, cutting depth and tool cutting edge angle) regarding surface roughness and burr formation during the milling of a mixed structure comprised of titanium and carbon fiber (stack). The parameters were varied from maximum to minimum, just as the tool cutting edge angle of the insert, through a full factorial design with 32 trials. The analyses were performed by measuring the surface roughness and burr size along with metallographic analyses through optic microscopy and scanning electron microscopy. The results showed that the surface roughness was higher for carbon fiber and burr size was higher for titanium. There were a number of tests with delamination of the carbon fiber, and the best cutting parameters to minimize surface roughness and burr formation were tool cutting edge angle of 45º, a feed rate of 0.028 mm/tooth, cutting depth equal to 0.26 mm and cutting speed equal to 150 m/min.

This paper presents the application of the Pareto-based multicriteria optimization technique to problems of increasing the efficiency of piezoelectric generators (PEGs). The optimization problem was solved for two types of generators: cantilever and stack. For the cantilever generator, the task was to optimize the design in such a way as to obtain the maximum output power for a given mechanical excitation. The optimization process was divided into several stages, which significantly reduced the amount of calculations. The task of optimizing the stack type for a given form of mechanical loading consisted in finding the geometric parameters of the generator at which the output voltage and power would be maximum. In the result of solving both problems, sets of geometric design parameters of PEGs were obtained, on the basis of which efficient transducers can be developed for specific operating conditions. It turned out that this technique is more suitable for optimizing the design of cantilever generators than for stack ones in given constraints. The solution of both problems was realized using the finite element method.

This article presents new algorithm for interval plotting ofthe function $y=f(x)$ based on the combined sampling. The proposedmethod synthesizes uniform and adaptive sampling approaches and providesa more compact and efficient function representation. During the combinedsampling, the polygonal approximation with a given threshold $\overline{\alpha}$between adjacent segments is constructed. The automated detectionand treatment of discontinuities based on $LR$ criterion are involved.Two implementations, the recursive-based and stack-based, are introduced.Finally, several tests of the proposed algorithms for different functionsinvolving discontinuities and several map projection graticules arepresented. The proposed method may be applied in geoinformatic formore efficient sampling the curves (map projection graticules, contourlines, or buffers).

In this article, I develop the concept of the “urban stack“ to elucidate how urban data infrastructures gain legitimacy and produce value in capitalist cities. Using two case studies, I study how the stack can incorporate both digital and non-digital components into its hierarchical topology. Heterogeneous components are strung together not only through technological means, as might be inferred from the emphasis on digitality in smart city literature, but also through the “soft infrastructures“ of legal designations, franchise agreements, privacy policies, and info-graphics. A topological comparison between the case studies yields three novel insights: first, urban data infrastructures exploit extant infrastructural conditions; second, technical and protocological operations at the control layer can be used to legitimate ontological claims; and third, technology producers employ a selective and asymmetrical display of information at the level of the interface in order to manage mobile urban populations in real-time. From these insights, it is possible to reach a more abstract conclusion: value production for urban data infrastructures hinges on their producers’ ability to enroll heterogeneous elements into their stacked configuration and to then use this configuration to control the flow of information.

A systematic optimization of several parameters significant in the fabrication of anode-supported micro-tubular solid oxide fuel cell via extrusion and dip coating is presented in this study. Co-sintering temperature of anode-support and electrolyte, the vehicle type and solid powder content used in electrolyte dip-coating slurry, electrolyte submersion time, cathode sintering temperature, powder ratio in the cathode functional layer, submersion time for the cathode functional layer and, submersion time and coating number of the anode functional layer are studied in this respect and optimized in the given order according to the performance tests and microstructural analyses. The performance of the micro-tubular cell is significantly improved to 0.49 Wcm−2 at 800 °C after the optimizations, while that of the base cell is only 0.136 Wcm−2. 12-cell micro-tubular stack is also constructed with the optimized cells and the stack is tested. Each cell in the stack is found to show very close performance to the single-cell performance and the stack with a maximum power of ~26 W at an operating temperature of 800 °C is therefore evaluated to be successful. • Micro-tubular solid oxide fuel cells are fabricated via extrusion and dip coating. • A systematic optimization of several fabrication parameters is presented. • Cell performance at 800 °C is improved to 0.49 Wcm−2 from 0.136 Wcm−2. • 12-cell micro-tubular SOFC stack is also constructed with the optimized cells. • Each cell in the stack shows very close performance to the single-cell performance. [ABSTRACT FROM AUTHOR]

Summary: Polypyrrole (PPy)‐based composites containing nanostructured VOx, PbOx, and MnOx are galvanostatically synthesized on exfoliated graphite papers (1.0 and 6.25 cm2) formed as a result of the intercalation with their metals. Both intercalation and synthesis are performed in the synthesis solution containing metal(II)tetrafluoroborate salts, pyrrole monomer, HBF4, H2O, Triton‐X 100 (TX100), and carboxymethyl cellulose (CMC). The mass loading of the composite at the electrode is maintained at 10 mg cm−2. Symmetric and asymmetric unit cells are prepared in polyvinyl alcohol (PVA)/H2SO4 (1:1) gel electrolyte using composites synthesized on the treated graphite paper electrode. The electrical properties of these cells are examined by electrochemical impedance spectroscopy and their capacitive properties by cyclic voltammetry and galvanostatic‐charge discharge test. The asymmetrical cell, prepared with PPy/PbOx/CMC composite having energy density and cycle life better than others, exhibits 7.77 Wh kg−1 and 0.51 kW kg−1 at a working voltage of 1.4 V, considering the total mass of all sub‐components. The three‐cell asymmetric stack design, which is prepared using these composite‐coated electrodes, achieves a coulombic efficiency of 76% at 4.2 V. Finally, an electronic control system (DC/DC buck‐boost converter) is designed and implemented to manage the charge and discharge cycles of single‐cell and bipolarly connected stack to operate the asymmetric supercapacitor arrays with high performance. [ABSTRACT FROM AUTHOR]

Copyright of Scientific Papers of Electrical & Control Engineering Faculty Technical University of Gdansk / Zeszyty Naukowe Wydzialu Elektrotechniki & Automatyki Politechniki Gdanskiej is the property of Gdansk University of Technology, Faculty of Electrical & Control Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soybean MON 87705 × MON 87708 × MON 89788 (three‐event stack soybean) was produced by conventional crossing to combine three single soybean events: MON 87705, MON 87708 and MON 89788. This combination is intended to alter the fatty acid profile in the seed (in particular increasing the levels of oleic acid) and tolerance to glyphosate‐based and dicamba herbicides. The Genetically Modified Organisms Panel previously assessed the three single soybean events and did not identify safety concerns. No new data on the single soybean events, leading to modification of the original conclusions on their safety have been identified. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicate that the combination of the single soybean events and of the newly expressed proteins in the three‐event stack soybean does not give rise to food and feed safety and nutritional concerns. In the case of accidental release of viable three‐event stack soybean seeds into the environment, this would not raise environmental safety concerns. The post‐market environmental monitoring plan and the reporting intervals are in line with the intended uses of soybean MON 87705 × MON 87708 × MON 89788. Considering the altered fatty acid profile of the three‐event stack soybean, a proposal for post‐market monitoring needs to be provided by the applicant. The GMO Panel notes that in the context of this application EFSA‐GMO‐NL‐2015‐126 the applicant did not provide a 90‐day study on MON 87705 soybean in line with the applicable legal requirements. Therefore, the GMO Panel is not in the position to finalise the risk assessment of soybean MON 87705 × MON 87708 × MON 89788 under the current regulatory frame. [ABSTRACT FROM AUTHOR]

The regulations on stack designs at thermal power stations (TPS) has been analyzed. It is demonstrated that the applicable guidelines do not consider all the actual problems encountered in designing stacks for TPSs, such as optimization of the stack construction cost and its effective operation. The stack cost depends on its height and diameter, which, at a given connected capacity, are affected by the gas velocity in the stack channel. At present, the effective stack design procedures do not contain the notion of this economically feasible, cost-effective index, and the stack diameter is selected based on the engineering-and-cost estimation calculation procedures, which have not been approved as mandatory standards. These procedures are supported by the planning-and-distribution model of the country's economic development. The article announces a universal method developed by the authors for calculating the optimal flue gas velocity for any model of economic development irrespective of the trend in prices and expenditures for the production of goods and services. To calculate the optimal flue gas velocity, one should only input initial data valid at the present stage. The calculated results of the price factors' effect on the optimal flue gas velocity for single-flue and multiple-flue stacks are presented. Verification of the procedure against the initial data as of 1975 yields acceptable results. [ABSTRACT FROM AUTHOR]

Mode disintegration using diagonal square slots, sliced corners of proximity fed microstrip antenna is proposed to obtain circular polarization (CP). Empirical formulation, redesign algorithm for degenerated mode resonant length are distinctiveness of work. Stacked dual band, dual CP antenna is designed using formulations. It results Right Hand CP (RHCP) at 944 MHz, Left hand CP (LHCP) at 1105 MHz with CP bandwidth of 5.1%, 5.6%. Diode switching and its position controls stub length for reversing sense of CP is proposed in another technique. It gives RHCP at 966 MHz, LHCP at 875 MHz with CP bandwidth of 5.1%, 5%. For both techniques gain of 7 dB, cross polar below 20 dB is achieved at both polarizations. Redesign Flexibility at preferred frequency ratio, ease in fabrication, installation makes it suitable for mobile, satellite communication. [ABSTRACT FROM AUTHOR]

CFRP/metal stacks are widely used in aeronautical field. Drilling such stack composite in single shot is still challenging because of different machining properties between CFRP and metal. Delamination often occurs at the exit of the composite which can affect the strength of the composite components. Elastic deformation of CFRP and metal plate occurs in drilling process and furtherly affects the drilling character and critical delamination conditions. The aim of this paper is to study the delamination during drilling of CFRP/metal stacks with deformation of CFRP and metal plate. Analytical mechanical models are proposed to predict critical thrust force of CFRP in the drilling process for two stacking sequences, respectively. The elastic deformation of CFRP and metal plate and the local deformation of uncut CFRP laminate in the cutting zone are taken into consideration. The values of critical thrust force and the influences of the deformation of CFRP and metal plate on critical thrust force are obtained based on the solutions of the model. A series of punching experiments with accurate remained uncut plies is conducted to verify the rationality of the proposed models. The results indicate that the prediction of the proposed model shows a close correlation with the experiment measurements. [ABSTRACT FROM AUTHOR]

This paper presents the application of the Pareto-based multicriteria optimization technique to problems of increasing the efficiency of piezoelectric generators (PEGs). The optimization problem was solved for two types of generators: cantilever and stack. For the cantilever generator, the task was to optimize the design in such a way as to obtain the maximum output power for a given mechanical excitation. The optimization process was divided into several stages, which significantly reduced the amount of calculations. The task of optimizing the stack type for a given form of mechanical loading consisted in finding the geometric parameters of the generator at which the output voltage and power would be maximum. In the result of solving both problems, sets of geometric design parameters of PEGs were obtained, on the basis of which efficient transducers can be developed for specific operating conditions. It turned out that this technique is more suitable for optimizing the design of cantilever generators than for stack ones in given constraints. The solution of both problems was realized using the finite element method. [ABSTRACT FROM AUTHOR]

Power generation performance and long‐term durability of ammonia‐fueled solid oxide fuel cell (SOFC) systems are investigated with SOFC stacks consisting of 30 planar anode‐supported cells. SOFC systems with three different operation modes are employed: direct ammonia, external decomposition and autothermal decomposition. A novel BaO/Ni/Sm2O3/MgO catalyst is newly developed for the external ammonia cracker, whereas a Co‐Ce‐Zr composite oxide catalyst is used for the autothermal ammonia cracker. Initial performance measurement and 1,000 h long‐term durability test of the stacks are conducted. The stack fueled with direct ammonia achieves 1 kW power output with 52% direct current (DC) electrical efficiency; a slight decrease in its performance compared with the stack with the mixture fuel of hydrogen and nitrogen is attributed to the decrease in the stack temperature caused by the endothermic ammonia decomposition reaction. The external ammonia cracker helps to maintain the stack temperature, improving the initial performance of the stack. The stack performance with the autothermal ammonia cracker is also comparable to those with the other operation modes. It is also demonstrated that the stacks fueled with ammonia have excellent stability during the long‐term tests and 57% energy conversion efficiency at ca. 700 W electrical output is achieved with the external ammonia cracker. [ABSTRACT FROM AUTHOR]

We have studied the resonant properties of circular optical nanoantennas as well as other shapes of optical antennas without requiring any fitting parameters. This allows for a deeper insight into scaling behavior and do faster further research since a desired simple tool is now available to design such nanoantennas. The theory has been applied to design antennas supporting various resonances at predefined frequencies to respond to the desire to have multi resonant antennas for applications. Raman sensors are extremely broad band resonators. Such circular patch nanoantennas consist in tailoring the dispersion relation and the complex reflection coefficient at will by carefully selecting a particular stack of layers. We have made to characterize the resonance behavior of the potentially simplest optical nanoantennas which is also called nanowire antennas. The nanowire as a plasmonic cavity, a resonance occurs when the phase accumulated on a single round trip amounts to multiple of 2π. This phase is determined by the propagation constant of the plasmonic mode supported by the nanowire and an additional phase on reflection at the wire termination. By fitting many resonance positions with different nanowire lengths, the phase change on reflection is determined. Such results are obtained only for a few simplified geometries. Nanoantennas are made from an arbitrary stack of homogeneous disks. Increasing the radius of a single disk toward infinitely and increasing its thickness yielded the reflection coefficient of surface Plasmon polariton propagating along a single metallic interface at a planar termination. The obtained results were in good agreement with previous results. [ABSTRACT FROM AUTHOR]

In this study, a solid oxide fuel cell (SOFC) stack has been successfully fabricated and tested by using direct natural gas. The main objective of this research was to achieve optimal long-term performance of the SOFC stack without carbon deposition by using low-cost natural gas as a fuel. The stack configuration was improved by a new interconnect design and made of cost-effective raw materials. In this respect, the stack showed maximum power of 31 W while 33 A current was applied at a flow rate of 1000 ccm for H2 (as fuel) and oxygen. Then, humidified natural gas was employed as an internal reforming technique, which showed degradation of 1.4% after 24 h. Maximum obtained power was 32 W under 33 A current at a flow rate of 1000 ccm. After 48 h of operation, 34 W of power was achieved at the current of 38 A. Therefore, the power was increased from 32 to 34 W after 48 h of operation in upper current. Finally, a suitable SOFC stack made of cost effective materials and using direct natural gas under appropriate conditions was fabricated and developed in this research.

Internal reforming methanol fuel cell (IRMFC) has potential applications in portable or stationary power supply system, but currently performance of the IRMFC is limited by the low hydrogen production of its reformer. In order to produce more hydrogen with less volume, in this paper a single channel serpentine packed bed reformer was designed, and its bed size was optimized by experiment and numerical simulation to enhance heat transfer and increase catalyst utilization. It was found that with the bed diameter from 5.8 mm down to 3.8 mm, the reformer temperature distribution was more uniform but the bed pressure drop increased a lot. Considering performance and pressure drop, the reformer of 5 mm was optimal, per milliliters of which could supply 9.8 mL/min hydrogen at 453 K, almost twice as much as that by A. Mendes et al with one‐third of their catalyst loading. The reformer was quite stable, and less than 10% decline in methanol conversion was observed during the 100 hours period at 473 K. When incorporated into an IRMFC single cell, power density of the single cell reached 0.45‐0.55 W/cm2 at 453‐473 K under CH3OH solution and air feed, the highest in existing reports. The main drawback has to do with low stability of the IRMFC single cell at high current density. [ABSTRACT FROM AUTHOR]

The distribution of the gas flow in a PEMFC stack is of paramount importance to the stack's performance and lifetime. Uneven flow distribution influences the flow rate through each cell, which in turn causes uneven distribution of the current flow of the entire cell stack and ultimately reduces the performance of the fuel cell stack. In this work, different simulation methods are compared, and large eddy simulations are selected to investigate the flow characteristics in a model stack and study the effects of operating conditions on flow sharing. The simulation results indicate different flow patterns in the inlet header and outlet header; the former features a turbulent entrance region that progressively transits to a laminar region, whereas the latter exhibits a complex flow with jets mixing downstream. Moreover, the flow patterns and distributions for different inlet/outlet configurations, i.e., U-type and Z-type, are investigated. The distribution of the flow through the unit cells for both configurations is different. The Z-type arrangement offers a more uniform flow distribution and has a smaller number of fluctuations than the U-type. The effects of different inlet flow velocity and jet inflow pattern are also studied. The findings from this work can provide guidelines to improve header design. • Numerical simulations of turbulent flow in a pair of model headers mimicking a mid-sized stack were performed. • Flow sharing and characteristics in the stacks were studied using different turbulence models. • Effects of different operating conditions on flow distribution were investigated. [ABSTRACT FROM AUTHOR]

Recently, metal-based solid oxide fuel cells (SOFCs) receive much attention as new power converting systems, and reliable sealing is an essential requirement for the metal-based SOFC stacks. In this study, metal-based SOFC stacks with a reliable sealing method are developed for transportation applications. For successful development, bolt-spring and hydraulic compression methods for stack tightening are discussed in terms of their applicability to vehicles. Then, detailed stack designs are developed to obtain sufficient compressive stress on the surfaces of the sealing gaskets based on the finite element method (FEM). To maintain the compression and heat insulation of the stack, a hot box is designed based on the thermogravimetric properties, shrinkage behaviors, and mechanical properties of sealing gaskets of mica and Thermiculite 866LS, and ceramic fiber insulating board. As a result, a 1-cell stack unit is successfully fabricated and tested based on the designs, and a sealing rate of 100 ± 0.78% is achieved at an operating temperature of 800 °C. This study investigates comprehensive stack and sealing design processes, and it has broad implications for reliable stack development. • A metal-based solid oxide fuel cell stack was designed for reliable sealing. • Bolt-spring and hydraulic compression methods were discussed for vehicles. • Finite element analysis was conducted for sufficient stress on sealing gaskets. • A hot box was designed to maintain compression and heat insulation of the stack. • A sealing rate of 100% of 1-cell stack unit was achieved at a temperature of 800 °C. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Sediment microbial fuel cells (SMFCs) can covert the biomass and organic matters in sediments into electricity. SMFC stack is an essential way for the application of SMFCs. The unit distance and number will be crucial for SMFC stacks applied in practical environments. This study showed that the power density of individual SMFC increased with the unit distance when compared with SMFCs with a small distance. For hydraulically connected serial stacks, increasing unit distance from 2 to 28 cm decreased the potential loss from 50.4% to 11.3%, but the power output did not increase with either unit distance or number of units due to higher internal resistance and electrode reversal. For hydraulically connected parallel stacks, increasing unit number from one to three multiplied the power output but no further power increase was observed with four and five units, indicating an optimal unit number (OUN) in parallel stacks due to ion conduction. Similar performance was shown when using SMFC stacks to power a light‐emitting diode and an environmental sensor. The results provide important information for improving the power and cost‐effectiveness of SMFC stacks. [ABSTRACT FROM AUTHOR]

This study characterized in-situ stress-fields and multi-scale fractures in the low porosity and low permeability Mississippian-aged "Meramec and Osage" intervals in the Anadarko Basin of central Oklahoma. As the two reservoirs' productivity is influenced by fractures, understanding fracture nature, frequency and distribution is important for the development of these reservoirs. The study implemented an integrated approach to characterize in-situ stress-fields and related fractures utilizing 3D seismic data, cores, petrophysics, and formation micro-imaging logs. Density of fractures was interpreted from integrated analyses of seismic, petrophysical, core, and FMI log data. Fracture orientations were determined from the seismic and FMI log data. Detected fractures in the "Meramec" interval preferentially occur in pervasively calcite-cemented rock with low porosity. Because of the adverse effect of calcite cementation, fractures did not significantly improve reservoir quality within the "Meramec" interval. In contrast, detected fractures in the "Osage" interval added sufficient porosity and permeability to overcome negative cementation effects and improved the overall reservoir quality. This study revealed a rotation of the horizontal stress orientations from ancient stress regimes to the present-day in-situ stress regimes. The study demonstrated the application of integrated seismic and non-seismic data in fracture and stress-field characterization, improved our understanding of the effects of fractures on reservoir quality to reduce risks associated with exploring low-porosity/low-permeability mixed carbonate and siliciclastic reservoirs. • In-situ stress-fields and multi-scale fractures characterization of Anadarko. • Fractures density interpretation using seismic, petrophysics, and FMI log data. • Fracture orientations were determined from the seismic and FMI log data. • Fractures did not significantly improve reservoir quality within the "Meramec" interval. • Fractures in the "Osage" interval improved the overall reservoir quality. [ABSTRACT FROM AUTHOR]

In this paper, a new method is presented for encryption of colored images. This method is based on using stack data structure and chaos which make the image encryption algorithm more efficient and robust. In the proposed algorithm, a series of data whose range is between 0 and 3 is generated using chaotic logistic system. Then, the original image is divided into four subimages, and these four images are respectively pushed into the stack based on next number in the series. In the next step, the first element of the stack (which includes one of the four sub-images) is popped, and this image is divided into four other parts. Then, based on the next number in the series, four sub-images are pushed into the stack again. This procedure is repeated until the stack is empty. Therefore, during this process, each pixel unit is encrypted using another series of chaotic numbers (generated by Chen chaotic system). This method is repeated until all pixels of the plain image are encrypted. Finally, several extensive simulations on well-known USC datasets have been conducted to show the efficiency of this encryption algorithm. The tests performed showthat the proposed method has a really large key space and possesses high-entropic distribution. Consequently, it outperforms the other competing algorithms in the case of security

Abstract Maize MON 87427 ×MON 87460 × MON 89034 × MIR162 × NK603 (five‐event stack maize) was produced by conventional crossing to combine five single events: MON 87427, MON 87460, MON 89034, MIR162 and NK603. The GMO Panel previously assessed the five single maize events and eleven of the subcombinations and did not identify safety concerns. No new data on the single maize events or the 11 subcombinations that could lead to modification of the original conclusions on their safety were identified. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicate that the combination of the single maize events and of the newly expressed proteins in the five‐event stack maize does not give rise to food and feed safety and nutritional concerns. The GMO Panel concludes that the five‐event stack maize, as described in this application, is as safe as and nutritionally equivalent to its non‐GM comparator and the non‐GM reference varieties tested. In the case of accidental release of viable grains of the five‐event stack maize into the environment, this would not raise environmental safety concerns. The GMO Panel assessed the likelihood of interactions among the single events in the 14 maize subcombinations not previously assessed and concludes that these are expected to be as safe as and nutritionally equivalent to the single events, the previously assessed subcombinations and the five‐event stack maize. The post‐market environmental monitoring plan and reporting intervals are in line with the intended uses of the five‐event stack maize. Post‐market monitoring of food/feed is not considered necessary. The GMO Panel concludes that the five‐event stack maize and its subcombinations are as safe as its non‐GM comparator and the tested non‐GM reference varieties with respect to potential effects on human and animal health and the environment.

Three microbial fuel cells (MFCs) with different volumes (S-, M-, and L-MFCs) were operated at individual flow (phase I) and serially connected flow modes (phase II for forward flow and phase III for reverse flow) at the same flow rate. The three MFCs showed different voltages and power generation according to the hydraulic and electric connection modes. The M- and L-MFCs showed a similar voltage at hydraulic series-forward flow mode (phase II). The principal component analysis (PCA) and Pearson correlation showed that voltage generation and power density were affected by volume, hydraulic retention time (HRT), chemical oxygen demand (COD) loading rate, removed COD, and internal resistances. When they were connected electrically in series and parallel, the stack showed relatively lower voltage loss (28–30%) compared to the voltage losses of the other stacks (43–94%). These results suggest an easy way to connect MFCs with different volumes can be a new option to avoid voltage reversal and minimize energy loss.

• Degradation caused by a moderate starvation of the reactant gases in a cell is reversible. • Damages produced by a severe gas starvation are irreversible. • MEA degradation caused by gas starvation increases the loss of phosphoric acid from the polymer. • The effects of gas starvation on a cell do not propagate to the neighboring ones. • A PEM fuel cell stack can still work with a MEA severely damaged due to gas starvation. Fuel and oxidant starvation are amongst the most critical phenomena affecting fuel cell durability. Reactant starvation during proton exchange membrane fuel cell operation can cause serious irreversible damages. In the present research, the effect of a selective induced starvation of reactant gases on the performance and degradation of a high-temperature PEM fuel cell is studied. A specifically designed 5-cell stack is used, which enables varying the gas supplied to any of the individual cells. The particularity of selectively starving only one cell in a controlled manner is one of the novelties of this study. Two different tests are performed actuating on the central cell (cell 3). They are denoted as moderate and severe starvation, depending on the intensity of the limitation imposed to the gases flowrate. Some relevant and novel results are obtained. It is verified that the performance degradation caused by a moderate starvation of the reactant gases in a cell is reversible. On the contrary, the damages caused by an aggressive gas starvation, which is also maintained in time (30 min), are irreversible. However, the behavior of the rest of the cells is barely affected by the gas starvation to cell 3. Thus, the other major novelty of the present work is the evidence/proof of the ability of a stack with a starved and highly degraded cell, to continue operating, although with a drastic reduction in the total generated current. [ABSTRACT FROM AUTHOR]

• Bi-modified Pt catalyst is applied to a direct formic acid fuel cell (DFAFC) anode. • Bi was irreversibly adsorbed on Pt catalyst by a simple synthetic strategy. • Bi-modified Pt/C showed significantly high formic acid oxidation reaction activity. • A DFAFC stack fabricated using Bi-modified Pt/C yielded a power of 300 W. • The simple synthetic strategy can be applied to achieving DFAFC stacks commercially. Formic acid is a chemical with a simple molecular structure containing hydrogen. This liquid at room temperature is easy to handle and has a low toxicity, and is thus in the spotlight as a fuel. In particular, formic acid is an excellent fuel candidate because it can be operated at low temperatures when applied as a fuel in fuel cells with a high theoretical open-circuit voltage (1.48 V). However, it has a drawback in that the electrode catalyst is deactivated due to the generation of CO intermediates when formic acid is oxidized during cell operation. Therefore, to prevent this, an irreversibly adsorbed Bi on Pt catalyst is applied to a direct formic acid fuel cell (DFAFC) anode because it is easy to synthesize and economical. Physical analyses such as transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) were conducted, and electrochemical evaluations were performed through half-cell and single-cell level tests. The results revealed that the formic acid oxidation reaction activity of the Bi-modified Pt/C was 13 times higher than that of the conventional catalyst at 0.58 V. Further, a DFAFC stack was fabricated using the Bi-modified Pt/C, which yielded a power of 300 W. These results suggest that a simple synthesis method can be applied to fabricating industrially available DFAFC stacks. [ABSTRACT FROM AUTHOR]