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Keywords Ash utilization; Canadian pulp paper mills; Biomass boiler ash; Fly ash; Bottom ash; Ash application Highlights * General ash characterization is not enough to find useful applications of ash. * Ash use in the liming agent requires different properties than ash use in concrete. * Ash must be characterized according to its application requirements. * PPM ash can mainly be used for concrete, ag lands, liming agent, and forest roads. Abstract Pulp and paper mill biomass boilers generate large quantities of ash in Canada with British Columbia (BC) being the highest ash generating province followed closely by Quebec. Generally, the generated ash is landfilled, particularly in BC, with only a small amount being used beneficially. It is anticipated that the difficulty associated with the management of ash will worsen over time as the industry increases its reliance on green fuel. Thus, there is a strong need to identify beneficial uses of pulp and paper boiler ash for the sake of environmental and economic sustainability. The purpose of this report is to provide the first step in this direction, a review of proposed or implemented uses for coal and hog (or wood) ash around the world. Considering both the properties of the ash and local opportunities, this could be the first step toward screening the applications that may apply to individual mills. Several large-scale practices use ash, such as land application (as a nutrient source or as a liming agent), use in the construction industry (as a replacement for cement or as a fill material), and reclamation of mine sites and stabilization of unpaved forest roads. In some cases, relatively small-scale applications have been used which included uses such as a compost component, agent for pH adjustment of liquid streams and slurries, blasting abrasive, and source of quartz for glass manufacturing to name a few. It is important to note that the chemical nature of both fly and bottom ashes can be quite variable due to the type of wood residues combusted as well as combustion equipment used and must be considered in identifying beneficial applications. Abbreviations AB, Alberta; ASTM, American Society for Testing and Materials; BC, British Columbia; CCE, Calcium Carbonate Equivalents; CCME, Canadian Council of Ministers of the Environment; CFIA, Canadian Food Inspection Agency; GHG, Greenhouse Gas; ITE, Inorganic Trace Element; LOI, Loss on Ignition; MSW, Municipal Solid Waste; NS, Nova Scotia; ON, Ontario; QC, Quebec; TNV, Total Neutralizing Value; XRF, X-ray Fluorescence Author Affiliation: (a) FPInnovations, Pointe-Claire, QC, H9R 3J9, Canada (b) FPInnovations, Vancouver, BC, V6T 1Z4, Canada * Corresponding author. Article History: Received 8 February 2022; Revised 29 June 2022; Accepted 9 July 2022 Byline: Allan Elliott [allan.elliott@fpinnovations.ca] (a), Talat Mahmood [talat.mahmood@fpinnovations.ca] (a), Abu Kamal [kamal.abu@gmail.com] (b,*)

Keywords Pulp and paper mill sludge; Land spreading; Waste management; Soil health; Soil ammendment Highlights * Land spreading paper pulp mill sludge (PPMS) offers economic and environmental benefit. * Characteristics and utility of PPMS vary with treatment level (primary vs secondary). * Co-application of N sources can prove beneficial in some cases. * Routine analysis and robust regulation prevent adverse outcomes from PPMS use. * Longer term studies on soil chemistry and ecology effects are warranted. Abstract It is estimated that >400 Mt of board and paper are produced globally per year, and that 4.3--40 kg (dw) of sludge like material, pulp and paper mill sludge (PPMS), is generated for every tonne of product. PPMS are now more widely reused in agriculture as a soil amendment due to their high organic content of 40--50% by weight, perceived low toxicity and possible liming capabilities. Within this review article historic and recent literature on PPMS land spreading are combined with knowledge of European and UK regulation to explore the benefits, potential impacts and viability of land spreading PPMS. The review reveals that risks relating to potential N immobilisation in soils post-application can be readily mitigated, if desired, by coapplication of an N source, or even pre-treatment of sludge via composting. The benefits to crops have been demonstrated emphatically, while negative ecological impacts under typical field application rates have not been observed to date. The case is therefore strong for continued land application of the material as an environmentally responsible and sustainable use option. However, there are currently gaps in the literature regarding longer-term implications of PPMS applications in agriculture and in regards to the possible presence of emerging contaminants in some PPMS materials, both of which have been identified as areas that merit further research. Author Affiliation: (a) School of Geography, Geology and the Environment, Keele University, Keele, ST5 5BG, UK (b) 4R Group, Control House, A1 Business Park, Knottingley Road, Knottingley, WF11 0BU, UK * Corresponding author. Article History: Received 11 July 2021; Revised 24 February 2022; Accepted 27 May 2022 Byline: Tomi Turner [t.turner@keele.ac.uk] (a,*), Rebecca Wheeler (b), Ian W. Oliver (a)

Keywords Greenhouse gases; Wood ash; Paper sludge; Microbial activity; Mineral nitrogen; Boreal soils Highlights * The effect of wood ash and paper sludge on acid soils was tested in incubation tests. * Both increased the soil microbial biomass, respiration, and net mineralization. * Greenhouse gas emissions were larger for paper sludge amended soils. * Supplementing biochar to wood ash increased soil CO.sub.2 fluxes. * Supplementing biochar to paper sludge or limestone ash reduced soil CO.sub.2 fluxes. Abstract Land-use change in the boreal forest region leads to agriculture to be carried out on acid, shallow and low fertility soils. To correct soil fertility and promote crop productivity, manure and inorganic fertilizers are added, increasing the risk for greenhouse gas emissions (GHGE). To reduce the reliance on synthetic soil amendments while taking advantage of locally relevant industrial by-products, wood ash (WA) and paper sludge (SL) have been proposed as soil amendments for a range of soil types. We posited that amending soils with WA, SL and biochar will improve soil health parameters and fertility of boreal soils. Microbial activity resulting to nitrogen losses and availability were assessed. WA had a stronger ameliorative effect on acid boreal soils compared to SL. Both WA and SL increased soil microbial biomass and basal respiration resulting in higher net mineralization and thus significant increases in CO.sub.2 emissions. Co-application of urea with WA or SL further increased net mineralization compared to when used independently. Conversely, the biochar's effect was short-lived and not significant. Nevertheless, addition of biochar was shown to reduce CO.sub.2 emissions in all cases except in WA amended soils. No significant differences were observed in CH.sub.4 emissions across all treatments. WA and SL may improve soil fertility and quality but could also contribute significantly to GHG emissions in acid boreal soils. Further research is recommended to assess the mitigating effect of various biochar feedstocks on GHG emissions when co-applied with WA and SL. Author Affiliation: (a) School of Science and the Environment, Memorial University of Newfoundland and Labrador, Corner Brook, A2H 5G4, Newfoundland and Labrador, Canada (b) Environmental Science Program, Memorial University of Newfoundland and Labrador, St. John's, A1B 3X7, Newfoundland and Labrador, Canada (c) Natural Resource Sciences, McGill University, Sainte-Anne-de-Bellevue, H9X 3V9, Québec, Canada * Corresponding author. School of Science and the Environment, Memorial University of Newfoundland and Labrador, Corner Brook, A2H 5G4, Newfoundland and Labrador, Canada. Article History: Received 2 November 2022; Revised 16 December 2022; Accepted 30 December 2022 Byline: Ayodeji O. Medaiyese (a), Jianghua Wu (a), Adrian Unc [aunc@grenfell.mun.ca] (a,b,c,*)

Keywords Citation rate; Impact factor; JIFs; WoS; Models; fsQCA Highlights * The paper analyses the citation rate of an article published in the tourism, leisure and hospitality field. * Number of references, author[combining acute accent]s reputation, and early citations have a major impact using regression techniques. * Using QCA, we find that the combinations of several factors are needed to obtain a highly cited paper. Abstract This paper identifies the main factors that affect the citation rate of an article published in the tourism, leisure and hospitality field. Using several regression techniques, it has been identified that the number of references for an article, the reputation of the main author, and obtaining early citations have a major impact on a document's citation rate. As well as this, by means of a quantitative--qualitative analysis (fsQCA), the most efficient combinations of factors that influence the number of citations received have also been identified. This paper is useful for researchers, editors and readers interested in improving the impact of their research. Author Affiliation: Universidad de Santiago de Compostela, Spain * Corresponding author. Article History: Received 12 June 2022; Revised 22 December 2022; Accepted 26 December 2022 Byline: Onofre Martorell Cunil [onofre.martorell@uib.es], Luis Otero González [luis.otero@usc.es] (*), Pablo Durán Santomil [pablo.duran@usc.es], Carlos Mulet Forteza [carles.mulet@uib.es]

Keywords Bentonite; Leachates; Shear strength; Hydraulic conductivity; Consolidation parameters Highlights * Engineering properties of two Indian bentonites are presented. * Unconfined compressive strength reduced in the presence of all three leachates. * Hydraulic conductivity of the bentonites increased due to leachates. * Concentration level of metals and bentonite's composition greatly influenced engineering properties. * Influence of the fly ash leachate is the most among all three. Abstract A rapid upsurge in urban and industrial developments leads to increased generations of solid wastes. The most accepted technique of waste discarding around the world is landfilling. Leaching chemicals from municipal dumping grounds can pollute the groundwater source and the surrounding environment without appropriate precautionary measures. Bentonite is a low-cost constituent used as a liner material in landfills due to its low permeability, high sealing ability, high specific surface area, and the ability to hold up the impurity migration through adsorption. However, leachate interaction with bentonite may alter its properties and reduce its usefulness as a barrier material in the long term. Also, bentonite having different chemical and mineralogical compositions will behave differently due to the leachate interaction. Therefore, it is necessary to compare the performance of various bentonites in the presence of leachates. In the present investigation, two Indian bentonites of different mineralogical compositions were studied for their change in the index properties, swelling, swelling potential, swelling pressure, hydraulic conductivity, consolidation parameters and shear strength properties in the presence of fly ash, sewage sludge and paper mill leachates. The outcomes showed that in the presence of all the leachates, liquid limit, free swell, compression index, swelling potential, swelling pressure, time to complete 90% of consolidation and shear strength dropped; whereas, hydraulic conductivity and coefficient of consolidation increased. Besides, the quality of bentonite prominently influenced the hydraulic, strength and swelling behaviour. The bentonite having a higher cation exchange capacity, liquid limit, specific surface area, and swelling capability undergoes a higher variability in the free swell (80.0, 73.8 and 76.9% decline), liquid limit (73.5, 61.7 and 69.2% decline), swelling potential (61.3, 55.7 and 51.0% decline), swelling pressure (53.3 and 56.4% decrease), and hydraulic conductivity (57.5, 8.6 and 41.1 times increase at a void ratio of 1.2) values when infused with fly ash, sewage sludge and paper mill leachates, respectively. The study also showed that the fly ash leachate interaction causes a higher variation in bentonite behaviour than sewage sludge and paper mill leachates. The study's findings would prove beneficial to design engineers for selecting bentonite types for landfill liners. Author Affiliation: Department of Civil Engineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India * Corresponding author. Article History: Received 22 June 2021; Revised 12 October 2021; Accepted 17 October 2021 Byline: Saswati Ray [r.saswati@iitg.ac.in] (*), Anil Kumar Mishra [anilmishra@iitg.ac.in], Ajay S. Kalamdhad [kajay@iitg.ac.in]

Keywords Hydrological properties; Paper mill wastes; Wood industry by-products; Heavy metals; Soil amendments; Potting media Highlights * Valorization of organic waste is important to improve environmental sustainability through recycling of valuable waste. * Herein we investigated the potential applications of wood ash and paper sludge as a potting media for horticultural crops. * Wood ash and paper sludge improved the physicochemical properties of podzolic soil. * Paper sludge was more effective than wood ash in improving soil hydrological properties for better plant growth. * Furthermore, the incorporation of biochar in the potting media enhanced water holding capacity. Abstract Background and objectives Organic waste management in environmentally sustainable way is important not only to reduce the negative impacts on ecosystems but also valorizing the waste resources. Herein we evaluated the potential of wood ash (WA) and paper sludge (PS) wastes from a pulp and paper mill as potting media and their effects on the physicochemical properties of podzolic soil. Methods WA, PS and biochar (BC) was mixed in different combinations with a sandy loam podzolic soil. Potting media treatments included: T1--soil (negative control); T2--Promix.sup.TM (positive control); T3--50%soil+50%WA; T4--75%soil+25%WA; T5--50%soil+50%PS; T6--75%soil+25%PS; T7--75%soil+25%BC; T8--25%soil+50%WA+25%BC; T9--50%soil+25%WA+25%BC; T10--25%soil+50%PS+25%BC; T11--50%soil+25%PS+25%BC, T12-- 25%soil+25%WA+25%PS+25%BC and replicated three times. Results Potting media treatments expressed significant (p < 0.00) effects on pH, bulk density, total porosity, field capacity, plant available water (PAW) and water retention curves. Potting media amended with WA showed high pH range (8--12) while PS amendments exhibited pH in range where most plant nutrients are available (6.5--7.5). Results depicted significantly lower bulk density, and increased total porosity and water holding capacity of potting media amended with WA and PS. BC addition further enhanced the water retention properties compared to combinations without BC. T6, T10 and T11 produced higher amounts of PAW with desired pH compared to T1 and T2. Conclusion WA, PS and BC showed high potential for developing podzolic soil-based potting media, but their effects on plant growth and elemental uptake need to be investigated. Author Affiliation: (a) School of Science and the Environment, Memorial University, Corner Brook, NL, A2H 5G4, Canada (b) Environmental Science Program, Faculty of Science, Memorial University, St. John's, NL, A1B 3X7, Canada * Corresponding author. School of Science and the Environment, Memorial University, Corner Brook, NL, A2H 5G4, Canada. Article History: Received 21 May 2021; Revised 18 September 2021; Accepted 20 September 2021 Byline: Muhammad M. Farhain (a), Mumtaz Cheema (a), Yeukai Katanda (a), Muhammad Nadeem (a), Bilal Javed (a), Raymond Thomas (a), Ratnajit Saha (b), Lakshman Galagedara [lgalagedara@grenfell.mun.ca] (a,b,*)

Keywords Breakthrough research; Machine learning; Twitter data mining; Topic model; Solar cell technology Highlights * We proposed a framework for identifying potential breakthrough research using machine learning method. * We found 8 potential breakthrough researches in the field of solar cell technology in 2015. * Twitter data mining could be used to assist in identifying potential breakthrough research. Abstract Breakthrough research may signal shifts in science, technology, and innovation systems. Early identification of breakthrough research is important not only for scientists, but also for policy makers and R&D experts in developing R&D strategies and allocating R&D resources. Researchers mostly use scientific papers data to identify potential breakthrough research, but they rarely make use of Twitter data related to scientific research and machine learning methods. Analysis of Twitter data is of great significance for us to understand the public's perception of potential breakthrough research and to identify potential breakthrough research. Machine learning methods can assist us in predicting the trend of events by utilizing prior knowledge and experience. Therefore, this paper proposes a framework for identifying potential breakthrough research using machine learning methods with scientific papers and Twitter data. We select solar cells as a case study to verify the valid and flexible of this framework. In this case, we use machine learning method to discover potential breakthrough research from scientific papers, and we use Twitter data mining to analyze Twitter users' sense of and response to the discovered potential breakthrough research, which aims to achieve a more extensive and diverse assessment of the discovered potential breakthrough research. This paper contributes to identifying potential breakthrough research, as well as understanding the emergence and development of breakthrough research. It will be of interest to R&D experts in the field of solar cell technology. Author Affiliation: (a) College of Economics and Management, Beijing University of Technology, Beijing, China (b) School of Computer Science and Engineering, University of New South Wales, Sydney, Australia (c) Department of Engineering and Technology Management, Portland State University, Portland, OR, USA * Corresponding authors. Article History: Received 7 August 2020; Revised 10 June 2022; Accepted 12 September 2022 Byline: Xin Li [lixinyz@bjut.edu.cn] (a,*), Yang Wen (a), Jiaojiao Jiang (b), Tugrul Daim [ji2td@pdx.edu] (c,*), Lucheng Huang (a)

Keywords Blockchain; Disclosure; Latent Dirichlet allocation; Security token offering; Topic modelling; White paper Highlights * An integrated framework of STOs success is proposed by combining topic modelling with other campaigns' indicators. * Company's energy consumption and green impact is one of the most dealt topics among all types of projects. * The technological components in the healthcare field is a topic related to the campaign success * Energy consumption and green issues must be adequately disclosed to affect campaign success. Abstract Security token offerings (STOs), based on blockchain technology, are attracting increasing attention as an innovative alternative means of venture financing. Information about specific STOs is generally provided in white papers. This study analyses the content of white papers using a unique sample of 188 STOs from 2017 to 2021 to identify which topic is related to campaign success. We leverage latent Dirichlet allocation (LDA) topic modelling to identify the topics and themes in white papers. Nine topics are identified through LDA: company description, distributed ledger technology components, energy and green issues, financial and legal issues, artificial intelligence, and tech applications in different industries--specifically, healthcare, manufacturing and construction, education, and financial services. We find that energy and green issues represent one of the most prominent topics among all types of projects and that their disclosure is positively related to the probability of campaign success and the amount of funding raised. Another prominent topic that affects campaign outcomes is technology in the healthcare industry, reflecting wider investment trends in this sector. Our results may help entrepreneurs to improve their campaign disclosures and present new issues for policymakers regarding investments in digital tokens. Abbreviations DLT, distributed ledger technology; ICO, initial coin offerings; IPO, initial public offering; LDA, latent Dirichlet allocation; MiCA, Markets in Crypto-Assets Regulation; MiFID, Markets in Financial Instruments Directive; STO, security token offerings Author Affiliation: (a) University of Milano-Bicocca Business and Law Department, via Bicocca degli Arcimboldi 8, 20126 Milan, Italy (b) The Open University, Walton Hall, Milton Keynes MK7 6AA, UK * Corresponding author. Article History: Received 21 December 2021; Revised 29 July 2022; Accepted 27 August 2022 Byline: Paola Bongini [paola.bongini@unimib.it] (a), Francesco Osborne [francesco.osborne@open.ac.uk] (a,b), Alessia Pedrazzoli [alessia.pedrazzoli@unimib.it] (a,*), Monica Rossolini [monica.rossolini@unimib.it] (a)

Keywords Ices; IR spectroscopy; Titan; Organic chemistry Highlights * Laboratory results from two recent papers on benzene ices are compared. * Multiple tests suggest conflicting results and possible corrections to them. * The data can lead to determinations of molecular abundances in extraterrestrial ices. Abstract Infrared spectroscopic results on benzene (C.sub.6H.sub.6) ices from two recent papers, one published here, are compared to each other and to literature results from 60 years ago. Qualitative and quantitative differences are described, partly in terms of spectral resolution, and errors in one paper are identified that, once corrected, could bring the two recent publications into agreement with each other. A solution is provided for an unexplained disagreement with the literature noted by the authors of one paper. It is concluded that the only accurate, extensive set of IR absorption coefficients, band strengths, and optical constants now available for amorphous and crystalline benzene are those recently published here by the author and a colleague. Suggestions are made for future work to change this situation. Author Affiliation: Astrochemistry Laboratory (Code 691), NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA Article History: Received 19 March 2022; Revised 12 May 2022; Accepted 15 May 2022 Byline: Reggie L. Hudson [reggie.hudson@nasa.gov]

Keywords Decolorization; Lignin; Adsorbent; Membrane; Black liquor; Adsorption Highlights * A critical study made on color removal from paper mill effluent using various methods. * Examined color removal efficiencies using conventional and advanced techniques. * Study on Cost analysis in color removal from paper mill effluent. * Future research suggestions described for better implementation of the processes. Abstract The pulp and paper industry consumes a huge amount of water and releases more polluted and colored wastewater every year. Many conventional techniques are used in the treatment of paper industry wastewater. However, for color removal from paper mill effluent, there is no proven method so far, on an industrial scale. Due to high energy input and high cost, there is an urgent need to find out a new technique that must be sustainable, economical, and environment friendly. Various methods have been investigated on bench scale and pilot scale also but no proven method for color removal on an industrial scale. The paper provides an overview of the color removal techniques from different sources of pulp and paper mill wastewater discharged by various industries. The review described various components involved in various processes for color removal from paper mill waste water. The present works focus on processes like chemical, chemical/physical, biological, physicochemical, and electrochemical applied in color removal from paper mill wastewater. The present review gives key information on the effectiveness, use, betterment, and limitations of numerous methods of treatment targeted at color removal from paper mill wastewater using various techniques still under evolution. Author Affiliation: Department of Chemical Engineering, Dr B R Ambedkar National Institute of Technology, Jalandhar, 144011, India * Corresponding author. Article History: Received 11 April 2021; Revised 8 August 2021; Accepted 8 August 2021 Byline: Amit Kumar [amit.marrar@gmail.com] (*), Nirmal Kumar Srivastava, Poonam Gera

Keywords Bibliometrics; Citations; Machine learning; Big data; SHAP Highlights * This study examines 14 factors that can influence the citation of papers. * CatBoost model and SCOPUS dataset are used to examine the influences. * SHAP interprets the model and suggests how the factors contribute to the citation. * The results show that selecting the right journal/conference is the most important. Abstract The number of citations is often used to estimate the impact of a study. Previous studies have investigated what factors of publications affect citations and how they affect citations. However, the findings of the studies were unable to reach a consensus because of the limited sample size, domain, and measurement. This study reviewed previous studies that addressed factors influencing citations and then identified 14 measurable factors. Approximately 33 million publications from the Scopus database were used to train and validate a CatBoost model. A SHAP framework was used to interpret the trained model by focusing on how salient factors affect the number of citations. The results showed that the year is a significant factor affecting the citation but not the priority factor. A publication source was presented as the most important factor contributing to the citation. Several implications and strategic approaches to maximizing the impact of a study were discussed. Author Affiliation: Future Technology Analysis Center, Korea Institute of Science and Technology Information, 66 Hoegiro, Dongdaemun-gu, Seoul 02456, South Korea Article History: Received 17 February 2022; Revised 30 June 2022; Accepted 18 August 2022 Byline: Taehyun Ha [taehyunha@kisti.re.kr]

Keywords Paper industry wastewater; Biohydrogen; Cathodes; Microbial electrolysis cells; Electrodeposits; Waste to resources recovery Highlights * The fabricated cathodes exhibited higher electrochemical catalytic activity in real paper industry wastewater. * MECs were used concurrently for energy recovery and treatment of real paper industry wastewater. * Reaction inside MECs can be enhanced by depositing Ni--Co--P based particle on electrode surface. * Ni-Co-P co-deposits attained the maximum H.sub.2 production rate of 0.16-0.06 [plus or minus]0.002 m.sup.3(H.sub.2) m.sup.-3d.sup.-1 with ~42 % COD reduction. * Higher biohydrogen production, cathodic efficiency and energy recovery were obtained with co --deposited cathode materials. Abstract Paper industries are water-intensive industries that produce large amount of wastewater containing dyes, toxicity and high nutrient content. These industries require sustainable technology for their waste disposal and MEC could be one of them. However, effective MEC operation at neutral pH and ambient temperature requires economical and efficient cathodes that are capable to treat indusial wastewater along with recovery of energy/biohydrogen. Co-deposits of Nickel, Nickel--Cobalt and Nickel--Cobalt--Phosphorous on the surface of SS and Cu base metals distinctly were used as cathodes in MEC for the concurrent treatment of real paper industry wastewater and biohydrogen production. MECs were utilized in batch mode at neutral pH, applied voltage of 0.6 V and 30 [plus or minus] 2 [degree]C temperature with paper industry wastewater and activated sludge as microbial sources. The fabricated Nickel--Cobalt--Phosphorous gives the higher hydrogen production rate of 0.16 [plus or minus] 0.002 m.sup.3(H.sub.2) m.sup.-3d.sup.-1 and 0.14 [plus or minus] 0.002 m.sup.3(H.sub.2) m .sup.-3d .sup.-1 respectively, with ~33--42 % treatment efficiency for a 500 ml wastewater in 7-day batch cycle in both the cases; while it is lowest in the case of the control cathodes (SS1 (0.07 [plus or minus] 0.002 m.sup.3(H.sub.2) m.sup.-3d.sup.-1) & Cu1 (0.06 [plus or minus] 0.004 m.sup.3(H.sub.2) m.sup.-3d.sup.-1)). It was also found that fabricated cathodes have the capability to treat industrial wastewater at ambient conditions efficiently with higher energy recovery. Prepared cathodes show enhanced hydrogen production and treatment efficiency as well as are competitive to some reported literature. Author Affiliation: (a) Department of Chemical Engineering, Indian Institute of Technology Roorkee, Roorkee, 247667, Uttarakhand, India (b) Department of Chemical Engineering, Madan Mohan Malaviya University of Technology, Gorakhpur, Uttar Pradesh, 273010, UP, India * Corresponding author. Article History: Received 12 January 2021; Revised 12 July 2021; Accepted 10 August 2021 Byline: Amit Kumar Chaurasia (a), Ravi Shankar (b), Prasenjit Mondal [pmondfch@iitr.ac.in] (a,*)

Keywords Waste paper ash; WPA hydration; Soil stabilisation; Leaching; Heavy metals Highlights * Ashes from a plant using 100% recycled paper to produce paper are studied. * WPFA and WPBA have cementitious properties. * The hydrated products are calcite, C--S--H gel, and Friedel's salt. * Implementation of WPFA on six different soils was successful. * A stabilised soil with WPFA can be categorised as an inert material. Abstract Waste paper fly ash (WPFA) and bottom ash (WPBA), derived from fluidised bed combustion of a paper recycling plant, exhibit cementitious properties owing to its mineralogical composition, and hence, could be proposed as a hydraulic binder. However, it may also contain some traces of heavy metals. Considering it is necessary to understand the effect of reusing any kind of waste on the environment, this study proposes of reusing WPFA/WPBA as a hydraulic road binder by evaluating its mineralogical composition and leaching activity. Chemical, physical, and mineralogical properties of raw WPFA/WPBA and the microstructural evolution of binders were carried out. Results showed that both ashes undergo hydration reactions while showing some cementitious properties by forming C--S--H gel, Friedel's salt, and calcite. According to the European standard EN 13282--1, both WPFA and WPBA can be categorised as N1 considering they reach 5.3 and 3.6 MPa, respectively, at 56 days. Furthermore, the mechanical performance of various soils was improved by using WPFA and WPBA as a binder. From the environmental point of view, the amount of barium in WPFA and WPBA, which is the main problem, was significantly decreased by using these ashes as a binder. Author Affiliation: Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya (UPC-BarcelonaTech), 08034, Barcelona, Spain * Corresponding author. Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya (UPC-BarcelonaTech), Jordi Girona 1-3, 08034, Barcelona, Spain. Article History: Received 23 November 2021; Revised 31 March 2022; Accepted 6 April 2022 Byline: Hani Baloochi [hani.baloochi@upc.edu] (*), Diego Aponte, Marilda Barra

Keywords Tax evasion; Socio-economic networks; Game theory Abstract This paper builds on recent insights from network theory and on the rich dataset made available by the Panama Papers in order to investigate the micro-economic dynamics of tax-evasion. We model offshore financial entities documented in the Panama Papers as links between jurisdictions in the global network of tax evasion. A quantitative analysis shows that the resulting network, far from being a random collection of bilateral links, has key features of complex networks such as a core-periphery structure and a fat-tail degree distribution. We argue that these structural features imply that policy must adopt a systemic perspective to mitigate tax evasion. We offer three sets of insights from this perspective. First, we identify through centrality measures tax havens that ought to be priority policy targets. Second, we show that efficient tax treaties must contain exchange information clauses and link tax-havens to non-haven jurisdictions. Third, we show that the optimal deterrence strategies for a social-planner facing a strategic tax-evader in a Stackelberg competition can be characterized using the notion of Bonacich centrality. Author Affiliation: (a) Ca Foscari University of Venice and Paris 1 Pantheon-Sorbonne, France (b) Paris School of Economics and Paris 1 Pantheon-Sorbonne, France * Corresponding author. Article History: Received 3 November 2020; Revised 10 January 2022; Accepted 26 March 2022 (footnote)[white star] This project has received funding from the ITN ExSIDE European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 721846 and from the ITN EPOC European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 956107. Byline: Garcia Alvarado Fernando [fernando.garcia@unive.it] (a), Mandel Antoine [antoine.mandel@univ-paris1.fr] (*,b)

Keywords Food waste; Collection bag; Paper; Bioplastic; Anaerobic digestion Highlights * Bioplastic and paper bags were tested with BMP and semi-continuous digestion tests. * Paper bags show a good degradability in both the tests (>74%). * The BMP tests on bioplastic bags indicate a good degradability (>71%). * Semi-continuous digestion of bioplastics with food waste shows a low degradability. * The degradability of bioplastics is influenced by physical factors. Abstract The amount of compostable bioplastics collected with the food waste is constantly growing, particularly due to the bags used for collection. According to the Italian legislation, compostable bioplastics must be accepted by all biological treatment plants, including aerobic and anaerobic facilities. Anyway, the compostability standard requires only the assessment of the aerobic degradability, while it is generally not required to test the behaviour under anaerobic conditions. This aspect is evaluated in the paper, where the anaerobic degradability of bioplastic bags used for the food waste collection is assessed. First, Biochemical Methane Potential (BMP) tests were performed on four commercial types of bioplastic bags, including those designed only for the collection of food waste and the shoppers, that can be reused for the same purpose. Subsequently, an innovative approach for this kind of substrate was applied, subjecting two bags to semi-continuous co-digestion tests together with the food waste. Both tests were performed by comparing the behaviour of bioplastic bags with that of an alternative collection paper bag. Finally, tests to evaluate the influence of physical phenomena on the degradation of bioplastics were performed to better understand the results of biological tests. BMP tests indicated a good degradability (>71%) of bioplastic bags, while semi-continuous tests showed a much lower degradability ( Abbreviations BDB1, bioplastic dedicated bag 1; BDB2, bioplastic dedicated bag 2; BSB1, bioplastic shopper bag 1; BSB2, bioplastic shopper bag 2; PB, paper bag Author Affiliation: (a) Politecnico di Milano, Department of Civil and Environmental Engineering (DICA), Piazza Leonardo da Vinci 32, 20133, Milano, Italy (b) Politecnico di Milano, Department of Chemistry, Materials and Chemical Engineering 'Giulio Natta', Piazza Leonardo da Vinci 32, 20133, Milano, Italy * Corresponding author. Article History: Received 17 August 2021; Revised 10 December 2021; Accepted 16 December 2021 Byline: Giovanni Dolci [giovanni.dolci@polimi.it] (a,*), Valeria Venturelli (a), Arianna Catenacci (a), Riccardo Ciapponi (b), Francesca Malpei (a), Stefano Ettore Romano Turri (b), Mario Grosso (a)