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The Chinese national standard for paper ash measurement cannot meet the requirements for accurate and rapid ash measurement in actual production and scientific research because of the long measuring time, tedious procedures, and large human error. This paper reviews some worldwide devices and methods for rapid measurement of paper ash, including ceramic fiber muffle furnace, microwave muffle furnace, the addition of ash adjuvant, dry samples method, direct combustion of paper samples, oxygen-enriched combustion method, chemical analysis method, and ray method, etc. The differences and relationships are identified among these devices and methods. By comparing the different ash measurement methods, the rapid ash analyzer based on X-ray technology has the obvious advantages of short measuring time and small error. Lastly, the present situation and the development potential of these devices and methods are discussed in this review. [ABSTRACT FROM AUTHOR]

Global energy consumption is increasing every year, and, despite their many negative impacts, fossil fuels are a major source of energy, but their reserves are gradually depleting. One of the promising but underutilized resources is plant biomass (phytomass). The main problem of plant biomass combustion is the low melting temperature of ash, but there are also problems with corrosion of heat exchangers and clogging of heat-exchanging surfaces. This work is concerned with the production of straw pellets in order to increase the melting temperature of ash by adding an additive. The paper sludge contains substances that can increase the melting point of ash and was therefore added to the pellet samples. This additive was mixed with straw in ratios from 90:10, 80:20 and 70:30 (straw/paper sludge). The use of paper sludge showed positive effects on increasing the melting temperature of the ash samples. The deformation temperature of the ash has already risen from 1020 to 1260 °C after the addition of 10% sludge, which is comparable to wood pellets.

The pulp and paper industry in Europe produces over 11 million tons of waste per year. Given high landfill operational costs, thermal coprocessing with biomass may be a viable management and valorisation option for such wastes. In this work, the analysis of biomass (wood sawdust), mixture of primary and secondary pulp mill sludge and their respective blends (50 wt.%, 60 wt.%, 70 wt.% of sludge) was assessed by thermogravimetric analysis. One of the possibilities to ensure valorisation of paper pulp mill sludge is its combustion in the form of pellets containing a different amount of sludge. Production of pellets samples was realised on laboratory experimental device. The measurements showed that increasing the content of paper sludge in the produced pellets reduced the calorific value and increased the ash content. This research deals also with the effect of paper sludge on the ash melting temperatures. The results indicated that a higher content of paper sludge in the pellets increased the ash melting temperatures. This advantage of paper sludge can be utilized in co-combustion of biomass with a low ash melting temperature. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher 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.)

This paper evaluates the environmental impacts of different alternatives for handling of sludge from paper and pulp mills in Sweden, using Life Cycle Assessment (LCA). The common practice of incineration of biosludge with energy recovery followed by landfilling of ash (System A) was compared with the alternative of digesting sludge anaerobically to produce biogas using different digestate residue management options. The digestate produced from anaerobic digestion (AD) was assumed to be incinerated for heat energy recovery in System B or pyrolyzed for biochar production in System C to be mixed with forest soils. The impact categories considered in this work are climate change, non-renewable energy use, mineral extraction, aquatic ecotoxicity, carcinogens and non-carcinogens. The LCA results demonstrate that the two proposed systems significantly reduce the environmental impacts of biosludge management relative to incineration. An 85% reduction in the aquatic ecotoxicity impact is achieved in System C, due to the reduced mobility of heavy metals in biochar relative to ash. System C, on the whole, outperformed the other two, leading the authors to the recommendation that the use of pulp and paper mill biosludge in biogas-biochar production systems is preferable to merely recovering energy from it. • Anaerobic digestion (AD)-pyrolysis and AD-incineration were modelled as biosludge treatment technologies. • Immobilization of the heavy metals in biochar significantly reduced aquatic ecotoxicity. • The lowest carcinogens and non-carcinogens impacts were offered by the AD-pyrolysis system. • From an environmental point of view, biogas-biochar is preferable to merely energy recovery. [ABSTRACT FROM AUTHOR]

This article covers the study of the nature of ash content of containerboard from waste paper, as well as fractional composition of ash. With increasing use of waste paper with white top layer and deterioration of conditions of collecting and storing waste paper at the storing fields, there is an increase in mineral impurities in the incoming waste paper. This fact leads to increased load on cleaning equipment and accelerated wear of working parts of sorters and mills. Ash content includes all mineral impurities without any division into fractions or sources of occurrence. Reducing the total ash content of products becomes quite difficult, because suppliers of cleaning equipment guarantee the efficiency of removing only those mineral contaminants, the size of which is greater than the a certain value (70…100 microns). Standard methods for determining ash content of paper and cardboard do not imply the possibility of determining the fractional composition. To solve this problem, the authors applied a method for determining the fractional composition of granular materials in a certified laboratory. The method of sample preparation for analysis was developed by the authors independently. Based on the results of the research, it was possible to identify the volume of the ash fraction that can be separated by means of cleaning equipment. This volume is mainly quartz sand of various degrees of grinding, and the other part of ash content is the filler, calcium carbonate, which cannot be effectively removed from the technical process due to the small particle size. To determine the content of calcium carbonate, qualitative and quantitative research methods were used - treatment with hydrochloric acid followed by washing and weighing of the resulting sludge. This test methodology and the results of the research work can serve as a basis for the need to install additional or upgrade the existing cleaning equipment. Unfortunately, at present there are no studies concerning abrasive ability of the main filler – calcium carbonate, and its influence on service life of the corrugator. Also, at the moment there are no data concerning critical size of ash particles, which lead to accelerated wear of the rolls. At the same time, determination of critical particle size is important from the point of view of setting up and upgrading of cleaning equipment of the stock preparation department of a typical paper mill processing waste paper raw materials. For citation: Zhirnov D.N., Dernova E.V., Gorazdova V.V., Dulkin D.A. Ash Content of Containerboard. Problems and Solutions. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 5, pp. 184–194. (In Russ.). https://doi.org/10.37482/0536-1036-2023-5-184-194

The valorization of paper sludge is a high-potential process to develop renewable fuels and chemicals, which can be integrated with pulp and paper mills. Calcium carbonate is the main ash component in sludge, which plays a role in buffering pH and potentially lowering the conversion during enzymatic hydrolysis. Therefore, it is important to investigate the effect of ash on sugar yields and examine pH change to introduce efficient and economical enzymatic hydrolysis of sludge. Carbohydrate conversion was enhanced when the ash was removed by fractionation. On the other hand, the highest sugar recovery was obtained when the sludge contained 20% ash content. The pH change during enzymatic hydrolysis was influenced by ash and explained why sludge-derived hydrolysate showed lower carbohydrate conversion. Therefore, a high shear process with the increased acid amount is suggested to prohibit the negative effect of ash and enhance the accessibility of cellulase to fibers. This study highlights the feasibility of using wet waste streams generated by the paper industry. • Enhanced carbohydrate conversion of sludge containing low ash after fractionation. • Enhanced carbohydrate conversion by lowering the starting pH environment. • Observed pH change during hydrolysis to understand the adverse effect of ash. • Obtained maximum sugar recovery when paper sludge contained 20% ash. • Provided the efficiency of enzymatic hydrolysis depending on the ash content. [ABSTRACT FROM AUTHOR]

The present study focused on the combustion of four types of briquettes made from paper and cardboard waste produced in Ouagadougou (Burkina Faso). Rotary and tubular kilns were used to study the combustion. The combustion mean temperatures, nitrogen, phosphorus and potassium (NPK) content in the ash and heavy metals content in the ash and the flue gas were analyzed. The combustion steady phase mean temperatures ranged from 950 °C to 750 °C were obtained according to briquettes type. The temperature favored the transfer of the heavy metal in the flue gas comparatively to the ash mainly for Hg, Cd and Pb. The Pb, Hg and Mn content in flue gas and the ash are higher than their content in the parent wood used for paper production due to the additive during the manufacturing process. The results showed a high content of heavy metal in flue gas produced by combustion of briquette made with office paper and in the ash for the briquette made of corrugated cardboard. Furthermore, the low heavy metal contain in the ash allow their use for soil amendment. However, ash contained a low proportion of NPK (less than 2%) which does not allow their usage as fertilizer alone.

Global energy consumption is increasing every year, and, despite their many negative impacts, fossil fuels are a major source of energy, but their reserves are gradually depleting. One of the promising but underutilized resources is plant biomass (phytomass). The main problem of plant biomass combustion is the low melting temperature of ash, but there are also problems with corrosion of heat exchangers and clogging of heat-exchanging surfaces. This work is concerned with the production of straw pellets in order to increase the melting temperature of ash by adding an additive. The paper sludge contains substances that can increase the melting point of ash and was therefore added to the pellet samples. This additive was mixed with straw in ratios from 90:10, 80:20 and 70:30 (straw/paper sludge). The use of paper sludge showed positive effects on increasing the melting temperature of the ash samples. The deformation temperature of the ash has already risen from 1020 to 1260 °C after the addition of 10% sludge, which is comparable to wood pellets. [ABSTRACT FROM AUTHOR]

Eichhornia crassipes biomass collected in Lake Cuitzeo, Mexico was analyzed to determine the chemical components (pH, ash, ash microanalysis, extractives, lignin, holocellulose, and alpha cellulose) in the whole plant, as well as segmented analysis in roots, stems, and leaves. The plant contained an ash content of 14.3 to 20.7% and extractives content from 21.8 to 35.6%. The inorganic elements detected were potassium (K), chlorine (Cl), calcium (Ca), sodium (Na), magnesium (Mg), silicon (Si), aluminum (Al), phosphorous (P), sulfur (S), manganese (Mn), iron (Fe), and titanium (Ti). In addition, low amounts of lignin (12.5 to 25.7%) and holocellulose (26.7 to 37.1%) were obtained. Thus, E. crassipes biomass could complement cellulosic fibers in pulping processes of low yield, such as the fibers used to produce handmade paper. [ABSTRACT FROM AUTHOR]

The use of waste from the regional production of waste wood, waste paper, and cardboard in the form of briquettes may be causing an increase in local emissions, both of major elements and trace elements. When burning paper and cardboard briquettes, more than 70% of Mn, Zn, As, and Pb is released into the air from the total content of trace elements in the fuel. The largest amounts of major and trace elements are released when burning paper briquettes (56 g/kg of fuel); half of these amounts are released from burning briquettes from waste wood and coal (23 g/kg of fuel). The pursuit of alternative uses for those cardboard components that are not suitable for recycling cannot be directed to the production of briquettes for residential combustion in the framework of the application of the principles of the circular economy. In particular, the high concentrations of undesirable elements in the emissions released in the gas phase into the atmosphere are an obstacle existing even when the parameters of the PM10 emissions of a boiler are met. This is related to the high ash content of the cardboard (13.5%). Waste paper or cardboard could be added to waste wood at a maximum of 10% to make the pollution produced comparable to the burning of coal briquettes. [ABSTRACT FROM AUTHOR]

The article presents the results of a hydrogeological survey aimed to substantiate the engineering recultivation of accumulation ponds of lignin mud by inwashing it with coal ash. The ash bed causes compression consolidation of lignin bed, leading to an increase in the pond seal margin. The mass exchange between the ash and the lignin mud is accompanied by changes in the hydrogeochemical conditions: the mineralization of the liquid phase of technogenic soils increases by a factor of up to 8, and the concentration of microcomplex increases to very high values. The analysis of the qualitative state of groundwater showed it to be tolerant to the effect of accumulation ponds. The moderate deviation from the local natural background is due to other pollution sources. The applied recultivation technology is effective and environmentally safe, though it needs modernization. The alternative technology, proposed by OOO VEB-Inzhiniiring, i.e., grouting the pond content, is extremely hazardous, and the implementation of the project involves considerable environmental risk because of the possible loss of pond containment. [ABSTRACT FROM AUTHOR]

Copyright of Uzbek Chemical Journal / O'Zbekiston Kimyo Jurnali is the property of Institute of General & Inorganic Chemistry of Academy of Sciences of Republic of Uzbekistan 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.)

The use of waste from the regional production of waste wood, waste paper, and cardboard in the form of briquettes may be causing an increase in local emissions, both of major elements and trace elements. When burning paper and cardboard briquettes, more than 70% of Mn, Zn, As, and Pb is released into the air from the total content of trace elements in the fuel. The largest amounts of major and trace elements are released when burning paper briquettes (56 g/kg of fuel); half of these amounts are released from burning briquettes from waste wood and coal (23 g/kg of fuel). The pursuit of alternative uses for those cardboard components that are not suitable for recycling cannot be directed to the production of briquettes for residential combustion in the framework of the application of the principles of the circular economy. In particular, the high concentrations of undesirable elements in the emissions released in the gas phase into the atmosphere are an obstacle existing even when the parameters of the PM10 emissions of a boiler are met. This is related to the high ash content of the cardboard (13.5%). Waste paper or cardboard could be added to waste wood at a maximum of 10% to make the pollution produced comparable to the burning of coal briquettes.

Copyright of Lucrari Stiintifice, Universitatea de Stiinte Agricole Si Medicina Veterinara Ion Ionescu de la Brad Iasi, Seria Horticultura is the property of University of Agricultural Sciences and Veterinary Medicine (Editura Ion Ionescu de la Brad) 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.)

In near coast navigation, buoys and beacons convey essential information about dangers. At night-time, selected buoys send out individual blink-sequences that are marked in sea charts. International regulations require that navigation officer on watch makes visual confirmation of objects and their type in order to navigate safely. With rapid developments of highly automated vessels, this duty needs be carried out by algorithms that detect and locate objects without human intervention. At night-time, this requires algorithms that decode blink sequences and are able to classify from this information. The paper investigates this problem and suggests an algorithm that solves the problem. Convolutional Neural Networks (CNN) with Gated Recurrent Units (GRU) are developed for classification. A dedicated architecture is suggested that includes both temporal and color decoding to obtain unique precision. We demonstrate how networks are trained on synthetically generated data, and the paper shows, on real-world data, how the suggested approach yields 100.0% accurate results on 44 real-world recordings while being robust to inaccuracy in actual blink sequences. Comparison with baseline signal processing and with a recent state-of-the-art 3D CNN model shows that the new blink-sequence classifier outperforms alternative algorithms. A showcase of the results of this work is available in this video: https://youtu.be/KEi8qNnKV2w. [ABSTRACT FROM AUTHOR]

In this paper, we study the waveform and passive beamforming design for intelligent reflecting surface (IRS)-aided wireless power transfer (WPT). Generalized multi-user and low complexity single-user algorithms are demonstrated based on alternating optimization (AO) framework to maximize the weighted sum output direct current (DC), subject to the transmit power constraints and passive beamforming modulus constraints. The input signal waveform and IRS passive beamforming phase shifts are jointly designed as a function of users’ individual frequency-selective channel state information (CSI). The energy harvester nonlinearity is explored and two IRS deployment schemes, namely frequency selective IRS (FS-IRS) and frequency flat IRS (FF-IRS), are modeled and analyzed. This paper highlights the fact that IRS can provide an extra passive beamforming gain on output DC power over conventional WPT designs and significantly influence the waveform design by leveraging the benefit of passive beamforming, frequency diversity and energy harvester nonlinearity. Even though FF-IRS exhibits lower output DC than the ideal FS-IRS, it still achieves substantially increased DC power over conventional WPT designs. Performance evaluations confirm the significant benefits of a joint waveform and passive beamforming design accounting for the energy harvester nonlinearity to boost the performance of single-user and multi-user WPT systems. [ABSTRACT FROM AUTHOR]

The growing concern about environmental pollution and the depletion of resources has led to a focus on the use of more sustainable materials. In light of this, the recycling and use of agricultural wastes is highly advanced and sought-after in the concrete technology field. Yearly, an enormous quantity of date palm waste (DPW) is produced, putting stress on the ecosystem and necessitating an urgent disposing method. For this reason, many researchers are looking into the feasibility of incorporating DPW for cement composites in an effort to improve the performance and sustainability of concrete. The use of DPW in the design of concrete and mortar mixes has a significant effect on both the fresh and hardened properties of the resulting composites. This paper reviews the basic information on the types and characteristics of DPW used in previous studies. In addition, the potential inclusion of DPW and its effect on cementconcrete performance are reviewed. This study further highlights the areas that need additional investigation for adopting these waste materials. This will advance academic research and benefit the sustainability of the construction industry. [ABSTRACT FROM AUTHOR]

In the field of historical buildings, the wide use of lime as a binder in various contexts of application emerges from a series of artistic and archaeological evidence in the Apulia (Italy) from the 4th century BCE to the 15th century CE. The large availability of carbonate rocks in the geological substratum from Daunian Subappennines to Salento areas strongly influenced the material culture of the region. In this paper, significant study cases were presented to bring to light the technological complexity, almost completely cancelled by the widespread presence of industrial products, in the use of lime over the centuries. Through examples of use from antiquity to the modern age in Apulia (Egnatia, Lamapopoli, Tertiveri, Siponto, Lucera and Monopoli sites), technological solutions indicating an ecological dimension of production were discussed, bearing witness to technologies on a human scale and sustainability. The comparison of petrographical (POM, SEM-EDS) and mineralogical (XRPD) results indicated the technological trend and custom for lime production in the Apulian region that starts from the choice of the stone to be calcined and the aggregates and passes through the modalities of lime hydration and preparation of the mixture up to the laying. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology 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.)

The research into and applications of wood origin traceability technology are of great significance for promoting the standardization and legality of the global timber trade. This paper focuses on analyzing the content of ten mineral elements and the ratios of stable isotopes δ13C and δ15N in ash samples. Furthermore, multivariate statistical analysis was conducted to assess the clusters and differences in mineral elements, as well as δ13C and δ15N, among the samples, for identifying the different factors used to trace the origin of ash imported from different regions. Through unsupervised clustering and supervised discriminant modeling, a highly accurate method for discriminant analysis was developed. The results reveal significant differences (p < 0.05) in the contents of Mg, Cu, and Sr, as well as δ15N, between European and American samples. Additionally, the normalized results of mineral elements and isotope ratios were then subjected to partial least squares–discriminant analysis (PLS-DA), resulting in the highest level of separation. This analysis achieved an overall accuracy of 96.2% in discriminating between samples of European and American ash. The chemometrics analysis method integrating stable isotope analysis with elemental analysis exhibited potential for discriminating between samples from European and American ash. [ABSTRACT FROM AUTHOR]

In this paper, we explore the data recovery procedures from ${e} \cdot $ MMCs. The ${e} \cdot $ MMC is one of the “managed” flash memory devices that are popularly used in modern digital devices as their storage media. The ${e} \cdot $ MMC, which consists of flash memory and the flash memory controller, optimizes the data input/output between the host device and the non-volatile memory through its standardized protocol. Its standardized structure and protocol makes forensic physical data acquisition simpler than handling the raw flash memory. However, its secure data purging features, such as Secure Erase and Sanitize, make data recovery from ${e} \cdot $ MMC a challenging task. In this research, we investigate inside the ${e} \cdot $ MMCs, and evaluate advanced data recovery procedures. By reverse engineering the structures of ${e} \cdot $ MMCs and accessing the internal flash memory, we discover that securely erased data is still recoverable from the internal flash memory. In some models, more than 99% of the securely erased data can still be recoverable by accessing the flash memory inside the ${e} \cdot $ MMCs. The data extraction method, along with experimental data recovery evaluation, will be explored in this paper. [ABSTRACT FROM AUTHOR]

A primary source of increased read time on nand flash comes from the fact that, in the presence of noise, the flash medium must be read several times using different read threshold voltages for the decoder to succeed. This paper proposes an algorithm that uses a limited number of rereads to characterize the noise distribution and recover the stored information. Both hard and soft decoding are considered. For hard decoding, this paper attempts to find a read threshold minimizing bit error rate (BER) and derives an expression for the resulting codeword error rate. For soft decoding, it shows that minimizing BER and minimizing codeword error rate are competing objectives in the presence of a limited number of allowed rereads, and proposes a tradeoff between the two. The proposed method does not require any prior knowledge about the noise distribution but can take advantage of such information when it is available. Each read threshold is chosen based on the results of previous reads, following an optimal policy derived through a dynamic programming backward recursion. The method and results are studied from the perspective of an SLC Flash memory with Gaussian noise, but this paper explains how the method could be extended to other scenarios. [ABSTRACT FROM PUBLISHER]

Gasification of lignocellulosic biomass in a fluidized bed gasifier is a preferred option for gaseous fuel generation and solid waste management. Erosion, slagging and agglomeration limit the wide adoption of this process. Agglomeration needs serious attention as it leads to defluidization and plant shut down. The present study considers the various aspects of agglomerate formation by the interaction of the inorganic elements (K, Na, Ca) and bed materials. Inexpensive and widely used bed material like silica sand is prone to agglomeration due to the formation of lower-melting alkali silicates. The mechanism involving the formation of agglomerates and ash behavior has been reviewed. K2SiO3 is the commonly formed lower-melting eutectic by the reaction of bed materials and compounds like KCl, K2SO4 and K2CO3 present in the bed. Investigations on various bed materials and their combined effects on bed agglomeration are summarized in this paper. Among the preventive measures, the use of different types of bed materials plays a vital role in the reduction of agglomerate formation, thereby increasing fluidization time. Olivine, dolomite, alumina sand, mullite, etc. are identified as some of the alternatives to the conventional bed materials. The detection of agglomeration using various experimental and online methods is also reviewed. This could further help in the abatement of agglomeration in the reactor without affecting process parameters. [ABSTRACT FROM AUTHOR]

The textile industry is considered a polluting industry due to the use of chemicals in production and excessive use of energy and water, plus the generation of toxic waste. In present, the significance of environmental pollution and related problems in the world had led to development and application of environmental friendly production methods that less polluted environment. Wool fibers are subjected to a number of water-based treatments that pollutes the environment. In a desire to make the wool industry to become more sustainable, this paper reports an ecological wool washing method by using three alkaline solutions based on ash obtained from burning wood type beech/oak/hornbeam and water. The mixture solutions used for manually wool washing has different concentration of lye (10% to 30%) and pH, respectively. The higher the pH of the alkaline solution, the more impurities are removed. The optical images of washed wool fibers presented in the paper show no damage on surface structure. Wastewater collected after wool washing was used as natural fertiliser for watering seeds of grass. Some measurements on blades of grass were done to see the effect of wastewater. The number of grass blades/unit area, average length and the uniformity regarding the length increased when watering was done with wastewater. [ABSTRACT FROM AUTHOR]

In this paper, we study a new model of defect memory cells, called partially stuck-at memory cells, which is motivated by the behavior of multi-level cells in non-volatile memories, such as flash memories and phase change memories. If a cell can store the q levels 0, 1, {\dots }, q-1 , we say that it is partially stuck-at level s$ , where $1 \leq s \leq q-1$ , if it can only store values, which are at least $s$ . We follow the common setup where the encoder knows the positions and levels of the partially stuck-at cells whereas the decoder does not. Our main contribution in this paper is the study of codes for masking $u$ partially stuck-at cells. We first derive lower and upper bounds on the redundancy of such codes. The upper bounds are based on two trivial constructions. We then present three code constructions over an alphabet of size $q$ , by first considering the case where the cells are partially stuck-at level $s=1$ . The first construction works for $u

In this paper, we study a model that mimics the programming operation of memory cells. This model was first introduced by Lastras-Montano et al. for continuous-alphabet channels, and later by Bunte and Lapidoth for discrete memoryless channels (DMC). Under this paradigm we assume that cells are programmed sequentially and individually. The programming process is modeled as transmission over a channel, such that it is possible to read the cell state in order to determine its programming success, and in case of programming failure, to reprogram the cell again. Reprogramming a cell can reduce the bit error rate, however this comes with the price of increasing the overall programming time and thereby affecting the writing speed of the memory. An iterative programming scheme is an algorithm which specifies the number of attempts to program each cell. Given the programming channel and constraints on the average and maximum number of attempts to program a cell, we study programming schemes which maximize the number of bits that can be reliably stored in the memory. We extend the results by Bunte and Lapidoth and study this problem when the programming channel is either discrete-input memoryless symmetric channel (including the BSC,BEC, BI-AWGN) or the $Z$ channel. For the BSC and the BEC our analysis is also extended for the case where the error probabilities on consecutive writes are not necessarily the same. Lastly, we also study a related model which is motivated by the synthesis process of DNA molecules. [ABSTRACT FROM AUTHOR]

Antioxidant enzymes are one of the most important links in the plant defense system to various types of environmental stress, so their response to a particular type of stress may indicate the sensitivity or tolerance of the plant species. Our paper studied the difference in antioxidative enzyme [catalase (CAT, EC 1.11.1.6), superoxide dismutase (SOD, EC 1.15.1.1) and Class III peroxidases (POD, EC 1.11.1.7)], isoenzyme pattern and activities between Rumex obtusifolius L. (Polygonaceae) plants grown on ash amended and uncontaminated soil. Modified SDS-PAGE electrophoresis revealed the presence of a new POD isoform in leaf samples growing on ash-amended soil, although the activity of POD in the leaves did not change significantly compared to control plants. On the other hand, in the roots of ash-growing plants POD activity decreased by 90%. Single CAT isoform was detected in both leaf samples, and results indicate 47% higher CAT activity in leaves of ash growing plants. Native electrophoresis detected two SOD isoforms in leaves and roots from the control plant. SOD isoforms were inhibited in the roots of plants grown on ash. The paper indicates the possible role of CAT, SOD and POD in the adaptive response of R. obtusifolius plants on ash amended soil. [ABSTRACT FROM AUTHOR]

This article reports on an advanced level physical laboratory experiment designed for college level undergraduate education and for scholars who need specialized training on using and interpreting Laser-Induced Breakdown Spectroscopy. The technical principle, experimental operation and sample preparation of Laser-Induced Breakdown Spectroscopy are introduced in detail. A presentation and discussion of the use of Laser-Induced Breakdown Spectroscopy in the traceability of four common samples is emphasized. Combining Laser-Induced Breakdown Spectroscopy with Machine Learning, two distinct datasets are constructed through the extraction of spectral features. Dimensionality reduction of spectral data is performed using Linear Discriminant Analysis, while the Random Forest model is employed for provenance classification. Finally, the interpretability of the Random Forest model is leveraged to explore the contributions of different spectral elements to provenance tracing. Results demonstrated the system's effectiveness in not only accurately identifying ash types but also in elucidating the influential chemical components, offering significant implications for material analysis and environmental monitoring. On an educational standpoint, this paper will allow any reader, in particular, undergraduate and graduate students, to gain a better understanding of the theory and practice of Laser-Induced Breakdown Spectroscopy and machine learning. [ABSTRACT FROM AUTHOR]

It is a continuous imperative to establish the most efficient process of conversion of primary energy from fuel through combustion, which also has the least possible harmful effect on the environment. In this time of expressed demands for decarbonisation, it also means the affirmation of the use of renewable fuels and the indispensable application of appropriate primary measures in the combustion furnace. At the same time, the efficiency of the combustion process depends on several factors, from the type and properties of the fuel to the ambient and technological settings for the process. In this regard, with the aim of determining the static characteristics of combustion, experimental laboratory research was carried out on the combustion of mixtures of brown coal with low heating value and a high ash content with waste woody biomass and different process conditions: temperature, staged combustion air supply (air staging) and in conditions of application of a third or additional fuel (natural gas, reburning technology). Applied experimental methods included the analysis of the combustion process on the basis of input (reactants) - output (products), including the analysis of the composition of flue gases, i.e. the determination of the emission of the key components of flue gases CO2, CO, NOx and SO2, as well as the analysis of the composition of slag, ash and deposits ash, i.e. assessment and evaluation of the behaviour of ash from fuel in that process. Based on the obtained research results, this paper shows the significant positive effects of the application of primary measures in the furnace - compared to conventional combustion: air staging - reduction of net CO2 emissions during co-firing with biomass and reduction of NOx emissions by up to 30%; reburning technology - additional reduction of CO2 and NOx emissions in proportion to the share of natural gas, e.g. at a combustion process temperature of 1350 °C and at a 10% energy share of natural gas during the co-firing of a mixture of brown coal and waste woody biomass, compared to the emission without the use of natural gas, a reduction of NOx emissions by 185 mg/mn 3 or by almost 30% was recorded. It was concluded, at the same time, the application of these primary measures in the furnace does not negatively affect the behaviour of ash from the fuel in the given settings of the combustion process. [ABSTRACT FROM AUTHOR]

The paper evaluates all important aspects related to V present in coal and its behaviour during coal combustion with particular attention paid to its potential extraction from ash and slag wastes. Due to great environmental benefits of co-combustion of coal and wastes, these alternative fuels and corresponding ash and slag counterparts were also taken into evaluation. Specifically, the paper summarizes V levels in world coals, in other related materials (alternative fuels, additives etc.) and in ash and slag residues including V speciation and discussion of its valence states. Theoretically predicted (equilibrium-based) calculations and species are compared with experimental results; due to a significant effect on mitigating CO 2 emissions, attention is paid also to oxy-fuel combustion conditions. With the aim to extract V out of the ash and slag residues, physical, chemical, and biotechnological separation methods are discussed in detail along with dominant affecting factors. The paper includes also concluding remarks and highlights the most promising trends and limitations thereby providing suggestions for future research. [Display omitted] [ABSTRACT FROM AUTHOR]

As countries around the world pay more attention to environmental protection, the corresponding emission regulations have become more stringent. Exhaust pollutants cause great harm to the environment and people, and diesel engines are one of the most important sources of pollution. Diesel particulate filter (DPF) technology has proven to be the most effective way to control and treat soot. In this paper, we review the latest research progress on DPF regeneration and ash. Passive regeneration, active regeneration, non-thermal plasma-assisted DPF regeneration and regeneration mechanism, DPF regeneration control assisted by engine management, and uncontrolled DPF regeneration and its control strategy are mainly introduced. In addition, the source, composition, and deposition of ash are described in detail, as well as the effect of ash on the DPF pressure drop and catalytic performance. Finally, the issues that need to be further addressed in DPF regeneration research are presented, along with challenges and future work in ash research. Over all, composite regeneration is still the mainstream regeneration method. The formation of ash is complex and there are still many unanswered questions that require further in-depth research. [ABSTRACT FROM AUTHOR]

The 3-D NAND flash memory architectures will be a future trend, because they provide high memory capacity without aggressively scaling down. A vertical-gate (VG) structure composed of polysilicon (poly-Si) channels is a promising 3-D structure that could facilitate realizing an extremely tight-pitch NAND flash memory cell with high memory capacity. However, the variability of the VG memory cell induced by grain boundaries in the poly-Si channels is a major concern for aggressively scaled-down memory cells. In this paper, a discrete-trap approach is applied to emulate the real trap effects in a 3-D memory cell, and the 3-D structure geometry effects and the variation in the threshold voltage ( VT) induced by the discrete grain-boundary traps are studied. Various \Delta VT behaviors related to the structure geometry and trap position are examined. The effect of varying the body thickness on the \Delta VT is stronger than that of varying the channel width. This paper presents various cases for using the discrete-trap approach to study the variability of VT in 3-D VG memory cells. [ABSTRACT FROM AUTHOR]

This paper presents the results of monitoring the behaviour of selected wood species exposed to a small ignition initiator. We specifically aimed to investigate the effect of retardant coating on the combustion process of the wood species spruce (Picea abies), red spruce (Larix decidua), Scots pine (Pinus sylvestris), ash (Fraxinus excelsior L.), beech (Fagus sylvatica), and oak (Quercus robur) when exposed to a small initiator of ignition. At the same time, we studied the effect of different types of fungicidal agents (based on N-(3-aminopropyl)-N-dodecylpropane-1,3-diamine; alkyl (C12–16) dimethylbenzyl ammonium chloride or 3-iodo-prop-2-inylbutylcarbamate) on the effectiveness of a flame retardant (containing ferric phosphate) applied to the selected fungicide-treated wood samples. The experimentally obtained mass-loss and flame-spread results were statistically evaluated using the QtiPlot software program. A significant dependence of mass loss and surface flame spread on wood species was the primary focus. It was only confirmed for the surface-flame-spread variable. The dependence of the effect of fungicide treatment on the effectiveness of the selected retardant was confirmed. Fungicidal coatings with the active ingredient alkyl/benzyl (C12–16) dimethylbenzyl ammonium chloride indicated the lowest mass loss rate and flame spread for all wood samples. [ABSTRACT FROM AUTHOR]

In this case study we compared the fertiliser properties of an industrial wastewater treatment sludge and a sludge ash to the requirements of the Finnish Fertiliser Product Decree. The sludge was obtained from the activated sludge wastewater treatment plant of a Finnish non-integrated pulp mill. The sludge was furthermore incinerated at a laboratory in a muffle furnace (850 °C) to obtain sludge ash. The total Cd (4.9 mg/kg d.m.) concentration in the pulp sludge exceeded the Finnish limit value (1.5 mg/kg d.m.) for fertiliser products used in agriculture. In the sludge ash, the total concentration of Cd (39 mg/kg; d.m.) exceeded the Finnish limit value (25 mg/kg d.m.) for ash fertilisers used in forestry. These results restrict the potential reuse options of these residues. However, from the utilisation point of view, the enrichment of essential plant macro-nutrients was most notable, resulting to the following total concentrations of these elements in the sludge ash: P (26,000 mg/kg d.m.), S (40,000 mg/kg d.m.), K (11,000 mg/kg d.m.), Ca (83,000 mg/kg d.m.) and Mg (10,000 mg/kg d.m.). Therefore, we conclude that, the converting of sludge into ash may promote the reuse of this wastewater treatment residue to a more value-adding fertiliser by-product to be used as a soil improver and growing medium in landscaping or landfills sites or other closed industrial areas, where heavy metal limit values for fertilisers are not applied in Finland. [ABSTRACT FROM AUTHOR]

At present, a large amount of rice straw ash is being dumped as waste creating soil and water pollution. The manufacturing of welding fluxes requires minerals which are mined out from the earth's crust creating environmental ill effects. This paper presents a novel methodology for utilizing rice straw ash in the manufacturing of submerged arc welding (SAW) fluxes. The chemical composition of the joints produced with the developed flux is well within the acceptable range of American Welding Society (AWS) specifications. Their tensile strength and joint efficiency are 8% and 9% more than the joints produced with a commercial flux respectively. Their bead geometries are comparable to the beads deposited with the commercial flux. The joints are sufficiently ductile and could easily pass the bend test. The weld metal exhibits a desired microstructure containing acicular ferrite. This technology may turn the rice straw ash into a blessing in disguise. [ABSTRACT FROM AUTHOR]

Locally produced soil amendments can play a vital role in sustainable agriculture, enhancing soil quality and crop plant growth. This study investigated the impact of locally sourced biochar (BC) and ash, obtained from Maerua crassifolia Forssk. (wood), and Saccharum kajkaiense, Melderis (grass) on soil properties and okra (Abelmoschus esculentus) biomass. We assessed different application rates (10% and 20%), either separately or combined with the potting soil/peat (Biomix). Biomix application reduced soil pH (7.9),and increased soil organic mater (OM) (51.9%), NO3-1 (17.5%) levels, water holding capacity (WHC) (22.9%), and dry biomass (37.7%) of okra compared no Biomix application. Among BC and ash amendments, grass ash excelled, increasing okra biomass by 132.7%, followed by wood BC and grass BC. However, wood ash had a slight negative effect on okra dry weight and also increased the soil EC (6.12 dS m-1). Wood ash had higher K levels (758 mg kg-1) but lower Na (159 mg kg-1) compared to control (51 mg kg-1 K and 235 mg kg-1 Na). Both BC amendments raised soil organic matter (OM) by 7.63-8.69%, while wood and grass ash slightly increased soil P (57.7-64.6 mg kg-1). However, wood and grass BC reduced soil P to 44 mg kg-1. Grass ash raised NO3 levels (25.5%) compared to the control. The interaction of Biomix with wood and grass amendments decreased soil EC, increased soil OM, NO3 level and plant dry weight of okra. Wood and grass BC (20%) with Biomix enhanced the soil OM by 11%. The combination of 10% grass ash and Biomix resulted in the highest NO3 levels at 170 mg kg-1. Furthermore, the combination of Biomix and 10% grass ash produced the most significant increase (204.3%) in plant dry weight compared to the control. In conclusion, locally sourced biochar and ash amendments, particularly grass ash in combination with potting soil/peat (Biomix), demonstrated significant potential to enhance soil quality and crop biomass, offering valuable insights for sustainable agricultural practices. [ABSTRACT FROM AUTHOR]

Biomass can be considered an alternative to coal in the production of heat and electricity. Many types of biomass are waste from agriculture and the food industry. This waste is cheap, readily available, and replenished annually. However, most agricultural and food industry wastes (sugar cane pulp, olive and sunflower oil production wastes, straw, etc.) have ash with a low melting point. This leads to a rapid growth of ash deposits on the heating surfaces of boilers; as a result, the actual efficiency of boilers in which waste from agriculture and the food industry is burned is 45–50%. Known biomass pre-treatment technologies that allow for the fuel characteristics of biowaste. For example, leaching of biowaste in water at a temperature of 80–240 °C makes it possible to drastically reduce the content of alkali metal compounds in the ash, the presence of which reduces the melting point of the ash. However, this biomass pre-treatment technology is complex and requires additional costs for drying the treated biomass. We proposed to use torrefaction for pre-treatment of biomass, which makes it possible to increase the heat of combustion of biomass, increase the hydrophobicity of biomass, and reduce the cost of grinding it. However, we are not aware of studies that have studied the effect of torrefaction on the chemical composition of ash from the point of view of solving the problem of preventing the formation of agglomerates and reducing the growth rate of ash deposits on the convective heating surfaces of boilers. In this paper, the characteristics of sunflower husk subjected to torrefaction in an environment of superheated steam at a temperature of 300 °C and in an environment of gaseous products at a temperature of 250 °C are studied. All experiments were conducted using fluidized bed technology. The resulting biochar has a calorific value of 14.8–23% higher than the initial husk. To assess the behavior of sunflower husk ash, predictive coefficients were calculated. Torrefaction of sunflower husks does not exclude the possibility of slagging of the furnace but reduces the likelihood of slagging by 2.31–7.27 times. According to calculations, the torrefaction of sunflower husks reduces the likelihood of ash deposits on the convective heating surfaces of the boiler by 2.1–12.2 times. According to its fuel characteristics, the husk, after torrefaction in an environment of superheated steam, approaches wood waste, i.e., can be burned separately without additives or mixtures with other fuels with refractory ash. [ABSTRACT FROM AUTHOR]

This paper presents a Ternary Content-addressable Memory (TCAM) design which is based on the use of floating-gate (flash) transistors. TCAMs are extensively used in high speed IP networking, and are commonly found in routers in the internet core. Traditional TCAM ICs are built using CMOS devices, and a single TCAM cell utilizes 17 transistors. In contrast, our TCAM cell utilizes only two flash transistors, thereby significantly reducing circuit area. We cover the chip-level architecture of the TCAM IC briefly, focusing mainly on the TCAM block which does fast parallel IP routing table lookup. Our flash-based TCAM (FTCAM) block is simulated in SPICE, and we show that it has a significantly lowered area compared to a CMOS based TCAM block, with a speed that can meet current (~400 Gb/s) data rates that are found in the internet core. [ABSTRACT FROM AUTHOR]

This paper presents a reliability-aware metadata allocation strategy called scatter-single-level cell (SLC) for multiple-level cell (MLC) NAND flash memory storage systems. In scatter-SLC, metadata is kept in least significant bit (LSB) pages and corresponding most significant bit (MSB) pages are bypassed. Without partitioning SLC and MLC blocks, scatter-SLC can eliminate the unbalanced lifetime between SLC and MLC blocks while achieving the similar error rate as the method to store metadata in SLC blocks. We implemented scatter-SLC on a real-hardware platform. The experiment results show that scatter-SLC can reduce uncorrectable page errors by 93.54% while incurring less than 1% time overhead on average compared with the previous work. [ABSTRACT FROM AUTHOR]

This paper presents a closed expression for the lightning induced voltage in short loops, which considers the effect of the return stroke speed. It is shown that the traditional expression that provides the induced voltage as the product of the current time derivative by the mutual inductance is a particular case of the expression developed in this paper, which holds when the return stroke propagates with the speed of light. The comparison between the results of the traditional expression and the new one is carried out for different distances from the lightning flash and different stroke current waveforms. The effect of the return stroke speed is also investigated, showing that the higher the speed, the higher the induced voltage. The effect of loop length is investigated, showing that the loop can be considered as electrically short if its dimensions are smaller than one-tenth of the product between the current front time and the speed of light in free space. [ABSTRACT FROM AUTHOR]

Municipal solid waste (MSW) is converted to various materials through treatment processes, which in turn distributes potentially toxic elements (PTEs) to recyclable materials. This study is focused on establishing an inventory of combustible wastes with the objective of identifying specific sources of PTEs (B, Cr, Cu, Zn, As, Sb, Ba, and Pb). The combustible wastes were classified into 26 components by the criterion, which can be conveniently identified by the public. Each component of the combustible wastes was ignited at 450 °C, to reduce organic matters and increase the proportional content of the target PTE, before undergoing inductively coupled plasma analysis. The inventory of PTE contents in the waste components was developed from the ash and the ignition loss of each component. The contribution of waste components to the total amount of PTEs was estimated based on the element content and the proportion in waste. Through this series of processes, specific sources of waste components containing PTEs were presented. This work can contribute to the reduction of toxicity of MSW and incineration residues that are to be recycled. [ABSTRACT FROM AUTHOR]

In this paper, an attempt was made to study the flotability of washery grade-IV (ash content between 28% and 35%) type of coking coal in terms of maceral components and to examine how each maceral group floats in the course of a time-wise batch flotation test. The objective of this paper was to evaluate the flotation characteristics of high-ash coking coal fines (of size <500 µm) in terms of the maceral components using different levels of collector (diesel oil) and frother (methyl isobutyl carbinol). The flotation test results were evaluated from the petrologic analysis, and the petrographic test results show that at equal level of collector and frother doses (0.5 kg/ton), 86% of the vitrinite maceral group floated into the concentrate in 120 s, and 77% of the mineral matter and 90% of pyrite were observed in the last two concentrates and flotation tailings. Proportionate distribution of the maceral components in flotation products was confirmed through the petrographic analysis. The different flotability of coal petrographic constituents was further investigated through surface characterization techniques such as contact angle, zeta potential, and Fourier transform-infrared spectroscopy. [ABSTRACT FROM AUTHOR]

The paper presents the researches undertaken for the superior capitalization, in the context of the circular economy, of the power plant ashes and other industrial wastes, in the construction materials industry. Taking into account the specific properties of the ash from the thermal power plant, a technological scheme was elaborated through which the recovery of iron oxides was pursued (their share being significant). Due to the hydraulic properties of power plant ash, similar to those of classical construction materials, laboratory research was conducted in order to develop a material usable in the construction materials industry with superior characteristics. [ABSTRACT FROM AUTHOR]

Emerging applications like machine learning in embedded devices (e.g., satellites and vehicles) require huge storage space, which recently stimulates the widespread deployment of large-scale flash memory in IoT devices. However, existing embedded file systems fall short in managing large-capacity storage efficiently for two reasons. First, prior arts store data structures of file systems either in flash or in main memory, which severely magnifies the scarcity of computing and memory resources. Moreover, the fine-grained metadata management in the existing embedded file systems induces significant energy consumption for large-capacity storage. In this paper, we propose a novel embedded file system, ELOFS, to tackle the above issues and manage large-capacity NAND flash on resource-scarce devices. ELOFS is made efficient through three novel techniques. First, we redefine the space management granularity and streamline the metadata to speed up the mounting performance. In addition, we design hybrid file structures to adapt dissimilar access patterns of embedded devices. Furthermore, ELOFS provides opportunities for in-depth cooperation with application-specific systems. We implement ELOFS with Memory Technology Device (MTD) interfaces, and the experimental results show that ELOFS outperforms YAFFS and UBIFS in terms of write, read, and deletions with orders of magnitude reductions on memory footprint and mounting time. [ABSTRACT FROM AUTHOR]

Arc faults have always been a concern for electrical systems, as they can cause fires, personnel shock hazard, and system failure. Existing commercialized techniques that rely on pattern recognition in the time domain or frequency domain analysis using a Fourier transform do not work well, because the signal-to-noise ratio is low and the arc signal is not periodic. Instead, wavelet transform (WT) provides a time and frequency approach to analyze target signals with multiple resolutions. In this paper, a new approach using WT for arc fault analysis in dc systems is proposed. The process of detecting an arc fault involves signal analysis and then feature identification. The focus of this paper is on the former. Simulation models are synthesized to study the theoretical results of the proposed methodology and traditional fast Fourier transform analysis on arcing faults. Experimental data from the dc system of a photovoltaic array is also shown to validate the approach. [ABSTRACT FROM PUBLISHER]

Phase change memory (PCM) has been proposed to replace NOR flash and DRAM in embedded systems because of its attractive features. However, the endurance of PCM greatly limits its adoption in embedded systems. As most embedded systems are application-oriented, we can tackle the endurance problem of PCM by exploring application-specific features such as fixed access patterns and update frequencies. In this paper, we propose an application-specific wear leveling technique, called Curling-PCM, to evenly distribute write activities across the whole PCM chip to improve the endurance of PCM in embedded systems. The basic idea is to exploit application-specific features in embedded systems and periodically move the hot region across the whole PCM chip. To reduce the overhead of moving the hot region and improve the performance of PCM-based embedded systems, a fine-grained partial wear leveling policy is proposed for Curling-PCM, by which only part of the hot region is moved during each request handling period. Experimental results show that Curling-PCM can effectively evenly distribute write traffic for a prime application of PCM in embedded systems. We expect this paper can serve as a first step toward the full exploration of application-specific features in PCM-based embedded systems. [ABSTRACT FROM PUBLISHER]