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In recent decades, the paper industry has undergone many changes, making this industry more lucrative, “greener”, and thus more attractive. Today, recycled paper is a key raw material for paper production. However, this intense growth has also increased the number of market players, making competition more intense and dynamic and causing frequent turmoil. In such an environment, planning procurement and forecasting the price of recycled paper is a big challenge, even for highly experienced procurement managers. In addition, paper production itself is a dynamic process that requires all key grades of recycled paper to be available at all times. Accordingly, managing the optimal level of recycled paper stocks is also a difficult task faced by the procurement unit. The goal of this paper is to address these challenges by developing a new model for the sustainable procurement of recycled paper in the paper industry with the help of the principles of strategic management. Specifically, we aim to enhance our understanding of the factors driving the complexity of recycled paper procurement management. To this end, we conducted a comparative case study in four European companies. To build cases, we collected secondary data on the sampled companies as well as primary data from interviews with top executives at these companies. On the basis of the results from the comparative case study, we propose a new model for the procurement of recycled paper that helps increase the accuracy of forecasting price trends and by extension overall procurement performance. In a nutshell, this paper seeks to improve procurement processes by reducing the complexity of the enterprise procurement unit as well as by offering guidelines for the maintenance of optimal stock levels of recycled paper.

This paper presents preliminary results on the possibility of incorporating stranded macroalgae into the papermaking process, analyses of the physical-mechanical properties of filter paper, with the addition of stranded macrophytic marine algae from Ulva rigida species obtained previously, results of SEM–EDX analyses of filter paper samples, and results obtained from the filtration of a wastewater from the metallurgical industry, using the improved filter paper samples. In the filter paper recipe, stranded macrophytic seaweed of the species Ulva rigida was added at different percentages of 0.5%, 1%, 2%, 4% and 8%, and the addition was calculated in relation to the absolute dry material. The physicomechanical properties analyzed are grammage, thickness, density, moisture, ash content, breaking load, breaking length, tear resistance, bursting resistance, folding endurance, porosity, smoothness, water absorption and Cobb60 index. Additional information related to the homogeneity of the distribution of elements in the paper mass was obtained by scanning electron microscopy with energy-dispersive X-ray analysis (SEM–EDX). The addition of macroalgae to the paper mass improved the strength characteristics of the paper, such as breaking load, breaking length, tearing resistance, folding endurance and water absorption. Following industrial wastewater filtration using filter paper with added seaweed, positive results were obtained in terms of reduction of total Cr, Cu, total Fe and Zn concentrations.

This article belongs to the Special Issue Sustainable Development of Nanotechnologies: Risks and Opportunities for Occupational Safety and Health., A paper sensor was designed in order to detect the presence of nanomaterials, such as ZnO and silica nanoparticles, as well as graphene nanoplatelets (GnP), based on fluorescence changes of carbon nanodots. Paper strips were functionalized with carbon nanodots using polyvinyl alcohol (PVA) as binder. The carbon nanodots were highly fluorescent and, hence, rendered the (cellulosic) paper stripes emissive. In the presence of silica and ZnO nanoparticles, the fluorescence emission of the carbon nanodots was quenched and the emission decay was shortened, whereas in the presence of GnP only emission quenching occurred. These different photoluminescence (PL) quenching mechanisms, which are evident from lifetime measurements, convey selectivity to the sensor. The change in fluorescence of the carbon dot-functionalized paper is also evident to the naked eye under illumination with a UV lamp, which enables easy detection of the nanomaterials. The sensor was able to detect the nanomaterials upon direct contact, either by dipping it in their aqueous dispersions, or by sweeping it over their powders. The use of the proposed optical sensor permits the detection of nanomaterials in a straightforward manner, opening new ways for the development of optical sensors for practical applications., This research was part of the Project “Nano and Key enabling technologies within the innovation processes: risk and opportunities in occupational settings by prevention through design (NanoKey__EPTR0003))”, funded by the Italian Workers’ Compensation Authority (INAIL) and coordinated in cooperation between the INAIL Department of Occupational and Environmental Medicine Epidemiology and Hygiene, and the Italian Institute of Technology (IIT).

The present study was carried out to evaluate the effects of different fungal species on the metal uptake from paper sludge by Hemarthria compressa L. Paper sludge (PS) in various concentrations (0, 30% and 60%) were used with four treatments of two fungal species (F0 = Control, F1 = Aspergillus niger, F2 = Trichoderma pseudokoningii, F3 = A. niger + T. pseudokoningii). Paper sludge as rooting medium steadily influenced growth and physio-biochemical attributes of H. compressa in F0. Results revealed discrete variations in growth attributes with different PS concentrations and each fungal treatment. The maximum damages in ionic homeostasis (Na+, K+, Ca2+, Mg2+) due to PS toxicity were evident in parallel with declined chlorophyll concentration. The highest growth, total chlorophyll and biomass of the plants were observed when PS was treated with combined fungal strains (F3). Translocation factor decreased with F3 that is indicative of changes in Cd, Pb, and Cu movement to shoot from root. The plants with combined fungal treatment also showed greater catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) activity. Ions, such as Ca, Mg, and Na, also increased gradually with combined fungal treatment. The correlation matrix displayed a close association among diverse fungal and PS levels with multiple plant attributes. PCA-Biplot confirmed the outcome of correlational analyses among different characters of H. compressa. The combined fungal mediate the extraction of heavy metals from the paper sludge by H. compressa recommends the high accumulation of heavy metal (HM) and possible reutilization of metal free sludge as a fertilizer, for application in cultivated fields. Furthermore, the effects of fungal species on HM attenuation in PS are linear and can be used in different habitats. Advancement in such research work will also be helpful in understanding the mechanisms and enhancing the ability of other native microbes to remediate metals.

Each year, a large amount of waste paper (WP) is generated in Japan, and due to the change in lifestyle with the COVID-19 pandemic, the WP collection and recycling system in Japan faces new challenges. Although the government of Japan has installed WP collection systems, the efficiency of these traditional WP collection systems is too low, and this causes inconvenience to the governments, residents, and other stakeholders. On the other hand, some recycling companies in Japan are trying to establish a nontraditional WP collection system by setting their own WP collection stations in cooperative supermarkets. Yet, the efficiency of this new system has not been clarified. This research aims to investigate the current status, operational characteristics, and the role of recycling companies’ WP collection stations in the Japanese WP collection system. By performing trade area analysis and stepwise OLS regression, this research will evaluate WP collection stations’ efficiency. Moreover, this research will also discuss how the new WP collection system improves WP collection efficiency and residents’ convenience. The results show that WP collection stations efficiency is particularly high in large supermarkets with many parking spaces and long business hours, as well as in areas with many families with children. Recycling companies’ WP collection system could create a system, which can satisfy resident, government, and recycling company interests at the same time.

In order to improve the hydrophobicity of xylan hemicellulose, a simple procedure of its chemical modification with alkyl ketene dimer (AKD), a non-toxic, cost-effective, and eco-friendly chemical, was performed. For this purpose, the reaction products of beech wood xylan and different amounts of hydrophobic AKD were used for paper surface treatment. Thus, the coatings of about 4.5 g/m2 were applied on both sides of base paper in single and three successive layers. To obtain a complete reaction between AKD and xylan hemicellulose, the coated papers were thermal cured (about 110 °C) and the effects of AKD content on the barrier (water, oil, and water vapours) and mechanical properties were analysed. The structural analyses by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) of coated samples emphasized the presence of β-keto-ester compounds as a result of the reaction between xylan hemicelluloses and AKD. This is confirmed by the improving of barrier properties as the AKD content in coating dispersion is higher. The good barrier performance and improved strength properties were obtained for the coated papers with xylan hemicellulose and 1% AKD applied on paper surface in three successive layers (about 4.5 g/m2). In this case, the water vapours transmission rate (WVTR) was 35% lower than those untreated and the resistance to air passing through coated papers was over 3 times higher compared with base paper. There are no results reported on the chemical reaction of xylan hemicelluloses with AKD as well as its application in coatings for paper packaging. In this context, the obtained results in this study can contribute to expand the applications area of hemicelluloses offering a sustainable strategy for the developing of food packaging papers with appropriate barrier properties using biopolymer coating materials.

Sustainable biomass production based on efficient carbon and nutrient recycling is crucial in materially efficient, sustainable biobased production. A circular bioeconomy model of the replacement of mineral fertilizers with recycled nutrients from pulp and paper mill sludge is tested here within a hypothetical case from Indonesia, Southeast Asia. First, the financial feasibility of the use of recycled nutrients originating from pulp and paper processes was analyzed in fast-growing pulpwood production. Secondly, the comprehensive social and environmental benefits of the practice were analyzed through qualitative sustainability analysis. The availability of the basic material of all required parameters referring to Indonesia limited the analysis period to be from 1996 to 2013. The establishment costs of a pulpwood plantation were adjusted according to a reference study, while the other data were compiled from various sources. The financial profitability of the circular model was analysed by using two indicators, net present value (NPV) and internal rate on return (IRR). The application of sludge-based recycled nutrients slightly increased the establishment costs in some circumstances but had no direct impact on the financial profitability, as the financial profitability was not sensitive to the establishment costs. The results showed that the financial profitability of biomass production is not sensitive to the plantation establishment and management costs. The profitability depends on the mean annual increment and product price. The qualitative analysis showed a holistic value of the practice that goes beyond the direct benefits. The use of sludge-based recycled nutrients in the production of pulpwood closed the economic loop, which is illustrative of the circular bioeconomy within the integrated pulp and paper sector including the raw material source, forest plantation.

A six day industrial trial using hydrochar as part of the carbon source for hot metal production was performed in a production blast furnace (BF). The hydrochar came from two types of feedstocks, namely an organic mixed biosludge generated from pulp and paper production and an organic green waste residue. These sludges and residues were upgraded to hydrochar in the form of pellets by using a hydrothermal carbonization (HTC) technology. Then, the hydrochar pellets were pressed into briquettes together with commonly used briquetting material (in-plant fines such as fines from pellets and scraps, dust, etc. generated from the steel plant) and the briquettes were top charged into the blast furnace. In total, 418 tons of hydrochar briquettes were produced. The aim of the trials was to investigate the stability and productivity of the blast furnace during charging of these experimental briquettes. The results show that briquettes containing hydrochar from pulp and paper industries waste and green waste can partially be used for charging in blast furnaces together with conventional briquettes. Most of the technological parameters of the BF process, such as the production rate of hot metal (&lt, 1.5% difference between reference days and trial days), amount of dust, fuel rate and amount of injected coal, amount of slag, as well as contents of FeO in slag and %C, %S and %P in the hot metal in the experimental trials were very similar compared to those in the reference periods (two days before and two days after the trials) without using these experimental charge materials. Thus, it was proven that hydrochar derived from various types of organic residues could be used for metallurgical applications. While in this trial campaign only small amounts of hydrochar were used, nevertheless, these positive results support our efforts to perform more in-depth investigations in this direction in the future.

It is important to classify academic papers in a fine-grained manner to uncover deeper implicit themes and semantics in papers for better semantic retrieval, paper recommendation, research trend prediction, topic analysis, and a series of other functions. Based on the ontology of the climate change domain, this study used an unsupervised approach to combine two methods, syntactic structure and semantic modeling, to build a framework of subject-indexing techniques for academic papers in the climate change domain. The framework automatically indexes a set of conceptual terms as research topics from the domain ontology by inputting the titles, abstracts and keywords of the papers using natural language processing techniques such as syntactic dependencies, text similarity calculation, pre-trained language models, semantic similarity calculation, and weighting factors such as word frequency statistics and graph path calculation. Finally, we evaluated the proposed method using the gold standard of manually annotated articles and demonstrated significant improvements over the other five alternative methods in terms of precision, recall and F1-score. Overall, the method proposed in this study is able to identify the research topics of academic papers more accurately, and also provides useful references for the application of domain ontologies and unsupervised data annotation.

Since schools cannot use face-to-face tests to evaluate students’ learning effectiveness during the COVID-19 pandemic, many schools implement computer-based tests (CBT) for this evaluation. From the perspective of Sustainable Development Goal 4, whether this type of test conversion affects students’ performance in answering questions is an issue worthy of attention. However, studies have not yielded consistent findings on the equivalence of the scores of examinees’ answering performance on computer-based tests (CBT) and paper-and-pencil tests (PPT) when taking the same multiple-choice tests. Some studies have revealed no significant differences, whereas others have exhibited significant differences between the two formats. This study adopted a counterbalanced experimental design to investigate the effects of test format, computerised presentation type, difficulty of item group, and administration order of item groups of different difficulty levels on examinees’ answering performance. In this study, 381 primary school fifth graders in northern Taiwan completed an achievement test on the topic of Structure and Functions of Plants, which is part of the primary school Natural Science course. The achievement test included 16 multiple-choice items. After data collection and analysis, no significant differences in the answering performance of examinees were identified among the PPT, CBT with single-item presentation, and CBT with multiple-item presentation. However, after further analysis, the results indicated that the difficulty of item group and the administration order of item groups of different difficulty levels had significant influences on answering performance. The findings suggest that compared with a PPT, examinees exhibit better answering performance when taking multiple-choice tests in a CBT with multiple-item presentation.

The construction industry uses a large amount of natural virgin material for differentgeotechnical structures. In Europe alone, 11 million tonnes of solid waste is generated per year asa result of the production of almost 100 million tonnes of paper. The objective of this research is todevelop a new geotechnical composite from residues of the deinking paper industry and to present itspractical application, e.g., as a backfill material behind a retaining structure. After different mixtureswere tested in a laboratory, the technology was validated by building a pilot retaining wall structurein a landslide region near a railway line. It was confirmed that a composite with 30% deinking sludgeand 70% deinking sludge ash had a high enough strength but experienced some deformations beforefailure. Special attention was paid to the impact of transport, which, due to the time lag betweenthe mixing and installation of the composite, significantly reduced its strength. The pilot retainingwall structure promotes the use of recycled materials with a sustainable design, while adhering togovernment-mandated measures. Nasl. z nasl. zaslona. Opis vira z dne: 28. 1. 2021. Št. članka 979. Abstract. Bibliografija: str. 16-17.

Studies on recycled materials emerged during recent years. This paper investigates samples&rsquo, sound absorption properties for panels fabricated of a mixture of paper sludge (PS) and clay mixture. PS was the core material. The sound absorption was measured. We also consider the influence of an air gap between panels and rigid backing. Different air gaps (50, 100, 150, 200 mm) simulate existing acoustic panel systems. Finally, the PS and clay composite panel sound absorption coefficients are compared to those for a typical commercial absorptive ceiling panel. The average sound absorption coefficient of PS-clay composite panels (&alpha, avg. in the frequency range from 250 to 1600 Hz) was up to 0.55. The resulting average sound absorption coefficient of panels made of recycled (but unfinished) materials is even somewhat higher than for the finished commercial (finished) acoustic panel (&alpha, avg. = 0.51).

To review the current state of resources and environmental sciences in China, this study assessed highly cited papers of five leading CSSCI journals sourced from the Chinese National Knowledge Infrastructure database. The fields of resources and environmental sciences were the research focus, and the bibliometric analysis software CiteSpace was used to perform co-occurrence analysis on keywords, authors, and research institutions based on bibliometrics and social network analysis. Furthermore, the research hotspots, scientist groups, and main cooperation models in the field of resources and environmental sciences in China were also explored. The results show that: (1) For 30 years, the interdisciplinarity of resources and environmental sciences has become more and more intense, and research themes have become increasingly extensive. The research hotspots of highly cited papers focused on energy, ecology, land, water resources, and sustainable development. In recent years, problems associated with energy and carbon emissions have aroused great interest. The ecological and sustainable development of resources and environmental elements has emerged as a future research trend. (2) An analysis of scientist-oriented networks shows that highly cited papers are mostly published by group authors. Scientists work closely within their respective academic groups, while intergroup academic cooperation is rare. Furthermore, connectedness between cooperation networks is poor, and scientists are largely connected through their research institutions. Cooperation among scientists is greatly affected by their geographical locations. Research institutions in the same region are more likely to cooperate. Beijing and Nanjing are high-producing areas of highly cited papers. The Institute of Geographic Sciences and Resources, CAS, is the most influential research institution. This paper introduces the state-of-the-art research hotspots of Chinese resources and environmental sciences to international academic circles and provides a basis for the research practice of resources and environmental sciences worldwide.

For economic reasons, increasing the use of various fibrous pulps with high lignin contents&mdash, i.e., chemothermomechanical pulp (BCTMP and CTMP), thermomechanical pulp (TMP), and semichemical pulp&mdash, is desirable. The relatively good quality and increased efficiency of these pulps make them attractive paper semi-products. In particular, they could alleviate the severe shortage of paper semi-products. Although mechanical pulp and semichemical pulp are achieving increasing quality with substantially increased wood efficiency, their production is often characterised by high consumption of electricity to defibre chips or refine high-lignin-content fibrous pulps. Technological, environmental, and economic evaluations of the manufacture and application of increased efficiency cellulose pulps that take into account potential profits from increased cellulose pulp efficiency and losses due to energy costs and degradation in the properties of the resulting paper are relevant and essential to paper mills. This article reports such an analysis. The authors have analysed the usable properties of ten cellulose pulps with various degrees of digestion and identified the optimum pulp that yields the optimum product properties, considering the yield, pulp refining time, which determines the cost of paper manufacture, and strength properties of the obtained paper.

The deinking of paper-based printed electronics is a growing concern regarding the increase of printed electronics products. The benefits of using paper-based substrates instead of polymer or ceramic for the single-use printed electrodes can contribute to sustainability goals. The use of invasive plant species for making paper substrates for printed electronics is a unique opportunity to have several environmental benefits. In this study, the recycling issue of these products through the use of the deinking technique was evaluated. Screen-printed electrodes printed on an invasive plant-based paper and commercial cardboard were deinked, and their optical, morphological, and silver residues in paper and corresponding water extract were analyzed. The invasive plant-based paper had higher silver content in the recycled paper sheets, which influenced the optical and surface resistivity and residue ink particle number. On the other hand, the surface-treated cardboard had lower silver particle content after deinking, but higher silver concentrations in the water extract. The results indicate that ink-paper surface and ink-fibre interaction and adhesion is vital in the ink silver particles binding during the deinking process.