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In order to obtain a lignin-based adsorbent with low cost, simple operation and no further modification, a calcium lignin adsorbent was prepared from chemical mechanical pulping (CMP) waste liquor by directly calcification from lime. The calcium lignin was characterized by BET, SEM, TEM, FT-IR and solid-state NMR analyses. The results showed that the molecular structure of the calcium lignin particles did not change when compared to sodium lignin, the formation mechanism of calcium lignin was revealed. The initial COD and lignin contents of CMP waste liquid were 54858 mg/L and 24.39 g/L, the conversion rate of lignin can reach 71.36% when was deal with lime. Thus, most of the lignin resources in the waste liquid were recovered. The middle-stage wastewater (MSWW) of pulping and papermaking was dealt with calcium lignin, the COD removal rate was up to 85.83%. The adsorption isotherms and kinetics were well fitted by the Langmuir model and pseudo-second-order kinetic model, respectively. Lime was regenerated from the used calcium lignin with high-temperature calcination, the conversion rate of calcium ions can reach 83.56%. Overall, the calcium lignin prepared by the one-step method exhibited great potential for effectively removing COD from middle-stage wastewater.

Excellent mechanical and electrical properties of graphene-based paper-like materials are essential for applications in flexible conductors, energy-storage devices, etc. The graphene oxide (GO) supernatant separated by centrifugation and ultrasonication has been used to prepare graphene oxide paper and reduced graphene oxide paper (rGOP) with high strength and conductivity. However, this method has cumbersome steps and low supernatant concentration, which greatly increases time and energy consumption, and is not suitable for rapid batch preparation of high-strength and high-thickness rGOP. Herein, a high-speed mechanical shearing method has been used to efficiently exfoliate graphite oxide suspension into high-concentration GO slurry with large lateral size, and rGOP has been further prepared by blade coating and HI acid chemical reduction. Compared with the product prepared by ultrasonic exfoliation method, the average area of GO sheets obtained via the mechanical shear exfoliation method can reach around 16.31 μm2. As a result, the mechanical properties and conductivity of the prepared rGOP have been increased by 30% and 23.5%, respectively, with the tensile strength and electrical conductivity of 478.2 MPa and 208.4 S/cm being obtained. The developed method is of great significance for the large-scale production and emerging applications of lightweight and high-performance rGOP.

The study is a first investigation of the feasibility to preserve recycled fillers (e.g. calcium carbonate, kaolin) from deinking paper sludge for newspaper production using an alternative approach respect to the actual methods. Deinking paper sludge was incinerated at 575 °C. The thermal stability of the incinerated sludge (ash) was evaluated by infrared analysis. Subsequently, the resulting ash was bleached by sodium dithionite. The particle size of the ashes was analysed by laser diffraction. The effect of recycled fillers on recycled paper pulp, after blending, was evaluated by the analysis of the physical and optical properties of the obtained paper sheets. Analysis showed the conservation of the calcium carbonate and other fillers’ molecular structure, both after incineration of the sludge and after bleaching. The dithionite treatment of the ashes resulted in ISO brightness levels of more than 70. The brightness was stable over one month. Paper sheets made by blending the bleached ashes with recycled paper showed an improvement of brightness and opacity but a decrease in terms of porosity and breaking length compared to paper sheets made without any filler. The proposed method still requires further studies to evaluate the economical application but offers an opportunity for the recycling of inorganic materials and valorisation of the sludge.

This study introduces a novel geotechnical composite material comprising two types of fill material sourced from the paper industry-deinking paper sludge ash (DPSA) and deinking paper sludge (DPS). Five composites with different DPSA and DPS contents were investigated. Two composites were selected for further analyses. The technology and procedure for composite installation were implemented in field tests. The composites with 80% and 70% DPSA exhibited the elasticity required to withstand minor landslide slip deformations, in addition to achieving sufficiently high values of uniaxial compressive strength. The composites had a low maximum dry density value, which led to fewer settlements in the entire support structure. The enhanced shear characteristics can enable the construction of a thinner retaining wall. The delay between preparation and installation of the composites was further investigated. The field tests confirmed that the composites with 80% and 70% DPSA can be installed on the construction site 4 h and even 24 h after mixing. In 2018, a retaining wall structure with 70% DPSA and 30% DPS was successfully implemented near a railway line using conventional technology as followed-up research to the herein presented study. Results have been derived from work performed in the scope of the H2020 Paperchain project in which novel circular economy models centered on the valorization of the waste streams generated by the pulp and paper industry as secondary raw material for several resource-intensive sectors, including the construction sector, have been developed. Environmental benefits are savings in natural raw materials, reduction of landfill disposal as well as CO2 emission reduction. Nasl. z nasl. zaslona. Opis vira z dne 16. 11. 2021. Št. članka 22363. Bibliografija: str. 12-13. Abstract.

The pulp and paper industry has a high potential to contribute to negative emissions through carbon capture and storage (CCS) applied to existing processes. However, there is a need to investigate how CCS solutions also can be combined with implementation of other emerging technologies in pulp and paper mills. This paper investigates the integration of a novel calcination process in two kraft mills and evaluates its potential combination with capture and storage of CO2 from the calcination plant. The alternative calcination process uses electric gas-plasma technology combined with steam slaking and allows replacing the conventional fuel-driven lime kilns with a process driven by electricity. The novel calcination process generates a pure, biogenic, CO2 stream, which provides an opportunity to achieve negative emissions at relatively lower costs. The potential reduction of greenhouse gas emissions when replacing the lime kiln with the plasma calcination concept depends strongly on the emissions intensity of grid electricity, and on whether fossil fuel or biomass was used as a fuel in the lime kiln. If fossil fuel is replaced and electricity is associated with very low emissions, avoided CO2 emissions reach ~50 kt/a for the smaller mill investigated in the paper (ca 400 kt pulp per year) and almost 100 kt/a for the larger mill (ca 700 kt pulp per year). Further emission reductions could then be achieved through CCS from the electrified calcination process, with capture potentials for the two mills of 95 and 164 kt/a, respectively, and capture and storage costs estimated to 36–60 EUR/tCO2.

Detecting the concentration of free chlorine is important for monitoring the quality of water. In this study, we report a nanohybrid paper-based chemiresistive sensor that can be used with smartphones to detect free chlorine ions. The sensor was fabricated using a simple and standardized coating process. The graphene and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) nanohybrid paper-based sensing device exhibited a more stable and intuitive response to free chlorine than that exhibited by the device using only PEDOT:PSS. The nanohybrid paper-based sensor was sensitive to free chlorine concentrations in a linear range of 0.1-500 ppm, and the limit of detection was 0.18 ppm. The sensor showed specificity for free chloride ions and detection capability in samples. The sensor was integrated as a module with an electric readout system, and the measured signals and results could be displayed in real time on a smartphone. Therefore, the proposed sensing platform is suitable owing to its portability, low cost, ease of use, and capability for on-site water quality measurement.

Paper has become the basic elixir in everyone's activities and usage of paper has increased day by day, the waste generated by paper is also enormous. The primary source of paper is wood (tree) yet, waste paper is environmentally good and biodegradable; however, it is the primary source of deforestation. Current research aims to find an alternate way to recycle paper in the biological approach. Hence in our work, twelve cellulose-producing bacteria were isolated, out of which one bacterial strain proved to be the best. Cellulase enzyme was extracted and purified, and used for enzymatic de-inking of photocopy papers. The optimal conditions for cellulase synthesis were at 60 °C, glucose as the only carbon source, and potassium nitrate as the nitrogen source. The enzyme demonstrated excellent de-inking at a lower pulp consistency of 3% with a 20% enzyme dose. The cellulose and hemicellulose levels decreased, which can be attributed to fiber breaking. Further, the changes in the functional groups identified by Fourier-transform infrared spectroscopy analysis and the changes in the surface morphology of the pulp fibers were obtained using scanning electron microscope analysis.

Objective: This study mainly focussed how foldscope can be used as an efficient viewable tool to detect in morphological and anatomical investigation of various bioactive medicinal plants. Microscope provides a beneficial instrument for visualization of living cells. Its cost is very high which is not affordable for rural based educational institutes. Foldscope is the ultra-affordable and versatile, paper microscope designed to be extremely portable, durable and to give optical quality similar to conventional research microscopes. Methods: For enhancing scientific temperament among rural children, Indian Born Scientist (Dr. Manu Prakash) has introduced an ultra-low-cost foldable origami-based approach for large-scale manufacturing of microscope, specifically demonstrating bright field, dark field and fluorescence microscopes. However, its potential as in research tool in the area of aromatic medicinal plants is still not known. The slides were prepared by own and were observed with the magnification power of 140X. Results: The result of the present study reported that the Foldcsope images revealed viable stained areas in the respective plant parts like trichomes, stomata, pollen grains, stem and leaf of different medicinal plants and indicating their live activities. Conclusion: Based on the attractive images captured from the Foldscope, the uses of foldscope were recommended to public. Previously we had organized some awareness cum demonstration programme regarding foldscope and its applications in the field of science education in the different educational institute of Erode District, Tamilnadu. Based on the clarity of images and easy handling of Foldscope the uses of origami microscope were recommended for higher studies.

The recycling of waste paper has been an effective way to achieve the environmental-friendly growth of papermaking industry. Focusing on the mixed-pulping process which has been generally employed, to ensure the required properties of the deinking pulp (DIP) and minimize the purchase cost of waste paper, an intelligent model scheduling the mixing ratio of waste paper was developed in the study. Primarily, driven by the field data of mixing ratio of waste paper and DIP properties, the prediction models of DIP properties were developed by SVM, GA-SVM, and BP-NN algorithms. Subsequently, based on the best prediction model, the scheduling model for the mixing ratio of waste paper was set up by NSGAII algorithm. The experimental results showed that, based on the obtained best BP-NN prediction model of DIP properties, the developed NSGAII scheduling model for the ratio of waste paper could achieve excellent scheduling results under the rigorous constraints and multi-objective. Compared with the previous study, the developed prediction and scheduling models in this study reduced the purchase cost of waste paper by 2.16%, and improved the acceptable proportion of DIP property from 56.07% to 100%.

Carbonization of biomasses is an effective and important approach to recycle biomass waste. The tissue papers are one of the most common household trash and waste lots of natural resources and energies. Herein, the one-step carbonization and activation treatment was applied on two kinds of tissue papers to transform them into porous carbons. It was found the precursor structure and composition as well as the calcination temperatures play key roles to control the pore structures. As the active materials of supercapacitor electrodes, the resultant porous carbons obtained from different paper precursors and calcination temperatures (700–900 °C) presented different electrochemical performances. The microporous carbons derived from the 700 °C calcination of the tissue paper using the wood pulp as the raw material showed high capacitance up to ~ 200 F/g, providing a simple but effective way to recycle biomasses.

Significance Populations living in remote rural communities would benefit from rapid, highly sensitive molecular, DNA-based diagnostics to inform the correct and timely treatment of infectious diseases. Such information is also becoming increasingly relevant in global efforts for disease elimination, where the testing of asymptomatic patients is now seen as being important for the identification of disease reservoirs. However, healthcare workers face practical and logistical problems in the implementation of such tests, which often involve complex instrumentation and centralized laboratories. Here we describe innovations in paper microfluidics that enable low-cost, multiplexed DNA-based diagnostics for malaria, delivered, in a first-in-human study, in schools in rural Uganda., Rapid, low-cost, species-specific diagnosis, based upon DNA testing, is becoming important in the treatment of patients with infectious diseases. Here, we demonstrate an innovation that uses origami to enable multiplexed, sensitive assays that rival polymerase chain reactions (PCR) laboratory assays and provide high-quality, fast precision diagnostics for malaria. The paper-based microfluidic technology proposed here combines vertical flow sample-processing steps, including paper folding for whole-blood sample preparation, with an isothermal amplification and a lateral flow detection, incorporating a simple visualization system. Studies were performed in village schools in Uganda with individual diagnoses being completed in

The biological deinking method using microbial enzymes is quite promising and rather eco-friendly. In this paper, we discuss about the impact of enzymatic deinking of newspaper pulp using ligno-cellulosic (cellulase, xylanase and laccase) and lipolytic enzymes. The individual treatment of paper pulp with enzymes (cellulase/xylanase) could enhance the paper brightness to about 32.86% whereas combinational effect could enhance only about 28.67%. There was a release of chromophores from phenolic and hydrophobic compounds released during the deinking process. Physico-chemical parameters of effluents were also found to be within the standard limits and the metals like iron, lead and zinc were not detected in the enzyme assisted deinking effluent sample. The heavy metals in the paper pulp was found to be reduced after enzyme treatment. The obtained effluent was found have low phytotoxicity and was safe for agricultural applications. Hence, the present report was found to be a suitable enzymatic deinking process which was eco-friendly that results in non-toxic effluents. The method also provides an avenue in water resource recycling within industries.

Herein, a fully paper‐based all‐solid‐state supercapacitor with functionalized cellulose paper as electrodes, carboxymethyl cellulose gel as solid electrolyte and cellulose paper as separator was fabricated. The electrode was fabricated by a conventional papermaking process with silver‐modified fibers and graphene oxide (GO)‐modified fibers followed by reduction of GO. The Ag‐modified fibers and GO‐modified fibers were obtained by in situ growth of Ag nanoparticles and self‐assembly of GO sheets on cellulose fibers, respectively. Ag‐modified fibers act as a flexible current collector with rich three‐dimensional interconnected electron transport pathways to make the reduced GO‐modified fibers as electrode materials to achieve high conductivity (1.93 Ω sq−1) and high‐rate capability. Simple drying can reduce 40% weight of the supercapacitor to facilitate transportation and storage, and its capacitance efficiency can be recovered by wetting when needed. This work opens up a new way of developing cheap, green and high performance full‐paper flexible electronics by conventional papermaking process.

Paper recycling is the most eco-efficient waste management option, since the use of recycled fibers reduces the need for virgin wood fiber and lowers energy consumption, and hence has a positive effect on the environment. The use of recycled paper is by far the highest in the packaging industry. In food packaging production, recycled paper is often favored over paper and board made from virgin fibers. However, due to the possible hazardous chemicals that can be found in recycled paper, there is a dilemma of how to overcome food safety issues while making food packaging more circular. The objective of the study was to determine if deinked office paper grades could be used as an alternative fiber source in the production of food packaging white top linerboards. For that purpose, three different types of digitally printed papers were submitted to a chemical deinking flotation in laboratory conditions, and the handsheets formed after each recycling trial were tested on the suitability for direct food contact. Evaluation of deinkability for each group of recycled prints was performed, as well. Deinkability was evaluated by calculating the flotation yield, pulp’s brightness and whiteness increase, ink elimination factor, determination of residual ink area, as well as ash content elimination. Food safety evaluation was performed by determining the content of heavy metals (Cd, Pb, Hg, and Cr VI), primary aromatic amines, diisopropylnaphthalenes (DIPN), phthalates, and polychlorinated biphenyls (PCB) from aqueous or organic solvent extracts of recycled paper pulp. The fastness of the fluorescent whitening agents was determined, as well. Of all evaluated deinking flotation efficiency parameters, only flotation yield and ash reduction by flotation were positively assessed. High content of residual ink particles detected after the flotation stage indicates that the flotation was not a successful method for the elimination of disintegrated ink particles, which was also confirmed by deficient results of ink elimination measurements and whiteness increase. Flotation proved to be the least efficient in the recycling of inkjet prints, where the lowest ink elimination, whiteness, and brightness values were achieved. As far as food safety assessment of deinked pulp is concerned, all tested deinked handsheets were found suitable to be used in direct contact with foods.

In this early study, new cement-bonded bi-composite fibreboard (FB) was made from water hyacinth (WaHy) and waste paper (WP). Ordinary Portland cement (PdCe) used as a binder was mixed with other two additives: gypsum plasters (GyPl) and wood ash (WdAh), in defined proportions to form bonding matrices. The WP and WaHy were pre-treated and a linked process was developed for the mixing and consolidation steps. The FBs produced were based on different proportions of composites, binder, and additives mixed. The FBs produced were made from different proportions of composites, binders, and additives. Improved tensile strength was observed for bi-composite FB from WaHy mixed with WP. In general, FBs having densities in the range of 0.50–0.57 g cm−3 were compared favourably with the ASTM and ANSI standards (95%), thus making the FBs a potential alternative for building and construction purposes. More elaborate research with advanced analytical techniques is hereby suggested.

Mercury intrusion porosimetry (MIP) is an inexpensive and common technique to characterize porous structures like paper. One major limitation of MIP is the lack of information about the arrangement of pores in the structure, information that is particularly relevant for multilayer structures such as thickness-structured paper. In this article, results from Synchrotron X-ray 3D microtomography are combined with MIP data to provide in-depth and improved information about the structures.

The use of SERS for real-world bioanalytical applications represents a concrete opportunity, which, however, is being largely delayed by the inadequacy of existing substrates used to collect SERS spectra. In particular, the main bottleneck is their poor usability, as in the case of unsupported noble metal colloidal nanoparticles or because of the need for complex or highly specialized fabrication procedures, especially in view of a large-scale commercial diffusion. In this work, we introduce a graphene paper-supported plasmonic substrate for biodetection as obtained by a simple and rapid aerosol deposition patterning of silver nanowires. This substrate is compatible with the analysis of small (2 μL) analyte drops, providing stable SERS signals at sub-millimolar concentration and a detection limit down to the nanogram level in the case of hemoglobin. The presence of a graphene underlayer assures an even surface distribution of SERS hotspots with improved stability of the SERS signal, the collection of well-resolved and intense SERS spectra, and an ultra-flat and photostable SERS background in comparison with other popular disposable supports.

The aim of this paper is to study the effect of reinking and pretreatment of waste banknote paper on its usability in the bioethanol production process. To this end, the tensile strength of worn banknote paper was first studied at different pH values. The sample with the lowest tensile strength was considered for the next sections. In the deinking process, NaOH at different concentrations (1%, 2%, 3%, and 4%) and in combination with ultrasonic treatment was applied. After deinking the pulp, two acidic and alkaline chemical pretreatments with concentrations of 1%, 2%, 3%, and 4% were used independently and in combination with ultrasonic. Enzymatic hydrolysis, following fermentation with Scheffersomyces stipitis, and crystallinity measurements were used to confirm the efficiency of the pretreatments. RSM Design Expert software was used to determine the optimal values by considering the three variables&mdash, enzyme loading, ultrasonic loading, and contact time for waste paper deinked (WPD) and waste paper blank (WPB) pulps. The results indicated that repulping was the most efficient at pH = 2. In deinking, the highest brightness was obtained using 3% NaOH in combination with ultrasonic. Between the acid and alkaline pretreatment, the acid treatment was more appropriate according to the resulting sugar concentration and weight loss. XRD tests confirmed that the lowest crystallinity index was obtained in the sample pretreated with 4% sulfuric acid in combination with ultrasonic. The highest sugar concentration in the enzymatic hydrolysis step was 92 g/L for WPD and 81 g/L for WPB. For the fermentation at 96 h, the highest ethanol concentration and process efficiency achieved were 38 g/L and 80.9% for WPD and 31 g/L and 75.04% for WPB, respectively. Our research shows that the deinking process can widen the utilization potential of waste banknote paper in biorefinery processes.

The COVID-19 pandemic has highlighted the need for diversity in the market and alternative materials for personal protective equipment (PPE). Paper has high coatability for tunable barrier performance, and an agile production process, making it a potential substitute for polyolefin-derived PPE materials. Bleached and newsprint papers were laminated with polyethylene (PE) coatings of different thicknesses, and characterised for their potential use as medical gowns for healthcare workers and COVID-19 patients. Thicker PE lamination improved coating homogeneity and water vapour resistance. 49 GSM bleached paper with 16 GSM PE coating showed high tensile and seam strength, and low water vapour transmission rate (WVTR). Phi-X174 bacteriophage testing revealed that paper laminated with 15 GSM coating hinders virus penetration. This research demonstrates that PE laminated paper is a promising material for low cost viral protective gowns., Graphical abstract Image 1

Materials for electronics that function as electrical and/or thermal conductors are often rigid, expensive, difficult to be sourced and sometimes toxic. An electrically and thermally conductive nanocomposite that is lightweight, flexible and eco-friendly could improve the environmental friendliness of the electronics sector and enable new applications. Considering this, we have fabricated electrically and thermally conductive flexible materials by functionalizing paper with nanocarbon conductive inks. Carnauba wax is emulsified in isopropyl alcohol and mixed with graphene nanoplatelets (GNPs) or with hybrids of GNPs and carbon nanofibers (CNFs). The percolation threshold of the hybrid samples is lowered compared with the pure GNPs composites, due to their increased filler aspect ratio. The hybrid samples also exhibit superior bending and folding stability. Densification of the coating to decrease their sheet resistance enables them to achieve as low as ~ 50 {\Omega} sq-1 for the GNP-based paper. The densification procedure improves the bending stability, the abrasion resistance, and the electromagnetic interference shielding of the paper-based conductors. Finally, the compressed samples show an impressive enhancement of their thermal diffusivity. The flexible and multifunctional nanocarbon coated paper is a promising electronic conductor and thermally dissipative material and, at the same time, can increase the environmental sustainability of the electronics sector., Comment: 27 pages, 4 figures

The industrial solid waste generation and its stockpile disposal have major environmental consequences. These consequences could be minimized through the solid waste application as a raw material in other industries. The current study focusses on the utilization of lime sludge with boiler ash synthesized nanosilica for production of belite based clinker at relatively lower temperature. Lime sludge was also used in combination with fly ash and boiler ash to check the synthesis of compounds at varying temperatures. Nanosilica was synthesized from pretreated boiler ash through alkali treatment and acid precipitation. The synthesized nanosilica has been characterized for specific surface area, crystallinity, surface functional groups and size. Three different mixtures, containing lime sludge with nanosilica, fly ash, and boiler ash are fired at temperatures ranging from 900 °C to 1200 °C and characterized for the synthesis of belite. Conventionally, belite is synthesized above 1200 °C, whereas the combined application of lime sludge and nanosilica reduces the temperature of belite synthesis to 900 °C without pre calcination or addition of any chemical stabilizer. In the case of lime sludge and boiler ash blend, belite formation takes place at the higher temperature (1100–1200 °C). Anorthite synthesis takes place in case of lime sludge and fly ash blend, due to high percentage of alumina present in fly ash. Lime sludge and nanosilica based belite clinker are used to develop newer cementitious binder. Hydration and strength properties of developed binder proved worthy as building materials. This study will present alternatives for sustainable utilization of lime sludge, fly ash and boiler ash in construction.

Civil Construction Industry impacts significantly the environment, being one of the most critic factors related to elevated production of Civil Construction Residue (CCR). Among CCR produced, the Kraft paper package acquires notoriety, due their large use on material packaging, such as Portland cement and lime, then, present a high production rate and offer contamination potential, lack of collection logistics and nearly any reuse. In this scenario, the study and development of alternative constructive materials which applies the sustainability concept and CCR recycling have acquired great relevance in the sector. It is highlighted the residue incorporation on masonry soil-cement blocks, due its block are not submitted to the sintering process. Then, the present research intend to study adobe blocks mechanical properties based on soil-cement reinforced with cellulose fibers obtained from Kraft paper recycling. The bricks were confectioned with 7% Portland cement content and with 0%, 8%, 10% e 12% Kraft paper fiber addition, being submitted to compressive strength test, water absorption test, durability test with wetting and drying and retraction analysis. It was verified the confectioned composites presented as a viable and interesting alternative on technical and environment range. All studied researches presented null retraction and compressive strength increase on cracked state, toughness increase and good performance about durability.

The emphasis of the current study was on the calcination of lime sludge, performed at different temperatures from 650°C to 750°C, which consumes less energy as compared to the industrial pr...

This Editorial introduces a Special Issue of papers from the SEE International Conference RADAR 2019, which took place in Toulon, France, 23–27 September 2019. The papers are expanded versions of ones that were judged in the reviewing process to be of the highest quality and relevance. Benefitting from the unique location of the conference centre on the French Riviera, the conference was given the theme ‘Sensing from sea to space’, attracting nearly 400 attendees from 26 countries from all over the world (Figure 1). Engineers and researchers coming from private or public sector (universities and laboratories) shared their knowledge and experience on radar topics of common interests from physics to signal processing, from sensor validation to system design, and also on emerging technologies based on artificial intelligence; all topics being supported by 200 papers presented either in oral (150 papers in 36 sessions), or poster sessions (50 papers). Figure 2 shows the range of topics of the papers. 1 FIGURE Conference attendees by country 2 FIGURE Conference paper topics

Paper electronics is an emerging technology to implement flexible and wearable electronics devices via ink printing process. This paper evaluates the feasibility of using conventional printing paper for coating process with graphene/cellulose ink. 4 different types of regularly used conventional printing papers were used as substrates in this work. The conductive graphene ink was prepared through exfoliation of graphite in cellulose solution. The paper substrates surface morphology and sheet resistance of the drop-casted conductive ink on each paper were analyzed and discussed. Glossy paper was found to be suitable paper substrate for the printing of the formulated ink due to its low surface roughness of 16 nm. The value of sheet resistance of the graphene/cellulose thin film can be lowered to 4.11 kΩ/sq by applying multiple drops. This work suggests that conventional printing paper may offer solution for highly scalable and low-cost paper electronics.

The use of vegetable oil (natural ester) in electrical devices like power transformers is increasing due to their high biodegradability and better safety. The lifespan of power trans- formers is mainly defined by cellulose insulation condition, which usually works together with dielectric oil as electrical insulation and also as mechanical winding protector and compactor. That is why the aim and results of this research shows us not only the dielectric parameters evolution, but also the relationship between the mechanical factors and the moisture content of thermal accelerated ageing processes, with commercial vegetable oil, of Kraft paper and Diamond Dotted Paper (DDP). These are two of the most common insulating materials in electric power transformers. In addition, the new tests have been done by a different method of paper ageing analysis. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement Nº 823969 - BIOTRAFO.

Organosolv lignin was used as stabilizer to synthesize Bentonite-Lignin nano zero-valent iron (BL-nZVI). Then FTIR, XRD, SEM and TEM were carried out to characterize this new material. Results proved that organosolv lignin can effectively prevent the aggregation of nano zero-valent iron particles. BL-nZVI was applied as particle electrodes and formed a three-dimensional (3D) electrode system with ruthenium/iridium coated titanium plates and acted as tertiary treatment process to dispose the pulp and paper secondary wastewater. The removal efficiency of the chemical oxygen demand (COD) and color of the effluent were selected as indicators to check the performance of the system. It was found that the removal efficiency of COD and color depended on the current density, electrolysis time, distance of electrode plates, initial pH value and particle electrode dosage. The optimal parameters of each factor were also determined by a series of single factor experiments. Under the optimum conditions, removal efficiency of COD and color can reach 87.6% and 93.1% respectively. Possible mechanism of the 3D electrode system with BL-nZVI particle electrodes for treatment of pulp and paper wastewater was also proposed.

A high quality graphene paper has been fabricated using drop-casting of a custom developed stable ink mixture. The graphene/ethyl cellulose mixture can produce graphene paper coating on Kapton substrate at fairly large scales by finely adjusting the viscosity of the ethyl cellulose solvent blend. It was possible to produce a morphologically intact 300 nm-thick stacked structures of high purity graphene platelets after annealing at 300 °C, as characterized by SEM, Raman Spectroscopy and AFM. The electrical resistivity of a large batch of samples was measured and the results thoroughly evaluated, using a design of experiments approach. The resistivity values achieved were found to be lower or comparable to the best results reported in the literature. As expected, resistivity is inherently related to the concentration of the as-prepared ink and subsequent annealing conditions. However, prolonged annealing time can deteriorate mechanical properties as determined by cyclic bending and shear tests. It is anticipated that the present graphene paper has potential use in flexible electronics applications since the lowest resistivity and structure achieved were generally unaffected by the range of mechanical loadings studied.

The use of deinking paper sludge (DPS) as a fertilizer instead of sending it to landfill could play a role in reducing greenhouse gases and improving soil properties. The objectives of this study were (1) to evaluate the changes in the physical (permeability and structural stability), chemical (particularly soil pH), and biological (microbial metabolic quotient (qCO2), microbial biomass soil CO2 emissions) of a calcareous agricultural soil following two successive annual amendments with three treatments (0, 30, and 60 Mg DPS ha&minus, 1&mdash, control, DPS30, and DPS60, respectively), and (2) to determine whether the addition of N-fertilizer to these treatments (controlF, DPS30F, and DPS60F, respectively) causes changes to soil fertility. The DPS application increased soil organic matter (+0.80%: DPS60 vs. control, and +0.35%: controlF vs. DPS60F), available phosphorus (+23.14 mg kg&minus, 1: DPS60 vs. control, and +14.34 mg kg&minus, 1: DPS60F vs. controlF), potassium (+0.6 g kg&minus, 1: controlF vs. DPS30F), and calcium (+0.28 g kg&minus, 1: DPS60 vs. control). The 60 Mg DPS ha&minus, 1 rate improved permeability and structural stability, regardless of the presence or absence of N-fertilizer. On the other hand, the 60 Mg DPS ha&minus, 1 rate without N-fertilizer lead to a decrease in total mineralization rate and qCO2, thereby indicating a reduction in CO2 emissions. The rate of 60 Mg ha&minus, 1 DPS could be effectively used to enhance the permeability and stability (soil restoration) and mitigate CO2 emissions, whereas the 30 Mg ha&minus, 1 rate could be used as fertilizer to improve the fertility of calcareous soils.

Reduced graphene oxide (RGO) multilayer sheets were synthesized using waste paper pulp as carbon source. Formation of RGO was confirmed by Raman spectroscopy. RGO was mixed with cement at different concentrations (0.001, 0.01, 0.05 and 0.1% w/w) to obtain graphene cement composites (GCC). RGO is supposed to impart hydrophobicity to cement; hence, the capillary test was conducted. Hydrophobic property of GCC was found to be dependent on time, concentration and temperature. Antimicrobial property of GCC was checked which included antibacterial and antifungal studies. GCC showed better antibacterial performance (90%) against gram positive bacteria (Bacillus subtilis) than the gram-negative bacteria (Escherichia coli, 85%). Gram negative bacteria possess structurally more complex cell membranes than gram positive bacteria; hence, it was more resistant to GCC. Our finding supports the concept of involvement of membrane bound macromolecules in antibacterial performance of RGO. GCC was also found to be effective (88% inhibition) against fungal strain (Aspergillus niger).

The corrosion-resistance properties of modified ultra-thin carbon paper (CP) different graphene oxide (GO) content used in proton exchange membrane fuel cells (PEMFC) are studied for the first time. Results show that CP with 1 wt% GO has distinguished corrosion-resistance property (corrosion current: 5.539E − 8A.cm−2, minimum weight loss and contact angle variation). And mechanism analysis was found that the CP-1GO-P had uniform florine coating on some area of carbon fiber while T-CP-P has little. Moreover, the addition of GO could introduce more C O and C O groups which interact with the florine atom, thus can strengthen the bonding of PTFE and matrix carbon effectively.

Direct coating of Si on an elastic carbon nanotube (CNT) network effectively addresses the rapid capacity fading of the Si anode. However, this strategy is hindered by the low Si tap density (Si < 50 nm) since sufficient void space has to be left for accommodating the Si volume change. Also, the mechanical properties of the CNT network as the elastic buffer matrix degrade significantly caused by side reactions of CNT with electrolyte. This work presents a freestanding paper-like anode consisting of a symmetrical sandwich-structured SiN/Si/SiN composite grown on CNT paper. This anode works well (∼259 μA h cm−2 under the current rate of 0.6C after 350 cycles, with a capacity retention of 73.8%) even when the CNT is filled by the composite without void space left for accommodating volume expansion. This is mainly due to the following synergistic effects: on one hand, the stress-compensation phenomenon in the symmetrical sandwich-structured composite balances the volume change-induced stress and thus the composite has a robust mechanical stability with an intact morphology during cycling. On the other hand, the intact composite avoids reaction of CNT with the electrolyte and thus the CNT retains excellent mechanical properties and serves well as the elastic buffer matrix. These two sides interact with each other, enabling the high anode performance.

A novel method was introduced to evaluate the quality of fiber material from paper for recycling. The new concept, fiber integrity value, its components, and its relationship with paper strength properties were examined in more detail. The effect of deinking and screening on fiber integrity value, and its component parameters was shown. The fiber integrity value is closely connected to the strength potential of the pulp. It was shown that when the bonding degree was also considered, there was very good correlation with the tensile strength, tensile stiffness, and compressive strength (SCT) values. The fiber integrity value concept can be determined based on data from in-line analyzers.

Coating of the paper surface against to microorganism to making it suitable for food packaging is crucial in terms of improving antimicrobial properties. Cuminum cyminum L. known as cumin and Prunus mahaleb L. have the abundant chemical compound. Cumin has antiviral activity that making it proper for coating due to its various components. Mahaleb as well has rich fragrance make it eligible for sugary snacks and chocolate package. After coating with such biomaterials, thanks to varied fatty acids impart protective feature from oxidation to paper surface. It was observed that the odor of substances was trapped from paper samples. Wrapping paper selected as a base paper in this study. Cationic starch used for emulsifying the coating chemical. Cumin and mahaleb added the starch emulsion and coating suspension applied on the top pile of the paper with # 0 drawdown bar. Coating application reduced the paper's tear index results but increase tensile and burst index results in both cases. Mahaleb gives better Cobb60 value and bursting and tensile index and comparing to Cumin. However, cumin coated papers tensile index results in machine direction was better than mahaleb. Both natural substances are suitable material as an additive to the coating.

Printing with natural inks to the paper essential for various area like wrapping paper for foodstuff, paper cups etc. Therefore, the development of stable and commercial natural ink is gaining importance. The production methods and the surfaces chemicals (coating materials, fluorochemicals, sizing materials etc.) of the paper affect the color of the natural inks, which applied paper surface. The aim of this study is to evaluate the effect of natural inks on various paper types. Ink samples are cyan, magenta, yellow, black colors prepared to have the closest color properties to the commercial inkjet printing inks in the market. Yellow Curcuma longa extract, red Rosa canina extract, cyan Indigofera tinctoria extract, black Alkanna tinctora extract selected to prepare natural ink. The differences between the commercial ink and the natural ink applied paper samples CIE L* a* b* color values were evaluated. The application made with a commercial inkjet printer. Then strength properties of paper samples evaluated and compared. According to results, bleached white chemical paper color results were closest to commercial ink

To clarify the socioeconomic factors influencing global paper and paperboard demand, a panel data analysis was conducted covering the period 1961–2014. This study used paper and paperboard demand as the dependent variable, and a country’s economic level, Internet usage rate, plastic packaging demand, and time trend as the explanatory variables. An inverse U-shaped quadratic relationship, such as an environmental Kuznets curve, was found between economic level and paper and paperboard demand, which saturates and begins to decline as economic level increases. The economic level representing the turning point differs significantly with the use, ranging from around 37,000 US$/person for newsprint paper to around 66,000 US$/person for printing and writing paper. For both newsprint paper and printing and writing paper, demand declines owing to the spread of the Internet as the economic level rises, although this reductive effect is greater for printing and writing paper than for newsprint paper. A substitution relationship is not found between wrapping paper and corrugated cardboard on the one hand and plastic packaging on the other hand as the economic level becomes higher.

The effects of doping of ZnO and Nb2O5 solids with Fe2O3 (1.4 wt%) and Ag2O (1.4 wt%) on its surface and catalytic properties were investigated, as well as its photocatalytic performance on the degradation of a pulp and paper wastewater (PPW). The catalysts were characterized by XRD, SEM, photoacoustic spectroscopy (PAS), NH3-TPD and textural analysis. The results obtained revealed that Fe2O3 doping of Nb2O5 conducted at 500 °C resulted in an increase of about 116% for SBET while Ag2O treatment exerted a decrease of 33% for SBET of the doped adsorbents. Doping ZnO with Fe2O3 or Ag2O led to an increase of 80% for SBET. Iron and silver doping also led to a decrease in band gap energy of at least 6%. The addition of 1.4 wt% Ag2O on ZnO followed by calcination at 500 °C resulted in an increase of 11% in the value of the reaction rate constant (kap) for COD reduction under UV radiation. The treatment of Nb2O5 with 1.4 wt% Ag2O increased by a factor of 2.04 the value of kap for the reaction taking place under VIS radiation. The catalysts partially reduced the organic load and the real colour of the wastewater, allowing the achievement of the specifications for release into rivers, so photocatalysis could be an alternative for pulp and paper wastewater final polishing.

Frequency Domain Spectroscopy (FDS) is proposed as a suitable diagnostic method in this paper for implementation on energized oil-paper insulation systems. In present FDS tests, the measurement method is only designed for offline applications. To overcome the deficiencies with the offline testing, this work investigates the feasibility of performing FDS measurements on energized transformers with the view to developing an online diagnostic tool using neutral connections as injection and measurement paths. In the proposed technique, a low-pass filter system is designed to remove the high frequency noise as well as the power frequency signals present in the measured neutral currents. The technique has been successfully applied in a laboratory environment on transformers with oil-paper insulation systems with different operational ages and is feasible for single-phase as well as 3-phase transformers with the accessible neutral points. Compared with the conventional FDS results, a nonlinear dielectric phenomenon is observed from the energized insulation systems as higher dissipation factor Tanδ values primarily due to the increased losses under power frequency voltage excitation. The degree of the nonlinearity is found to correlate well with the degradation status of insulation systems under test.

Pulp and paper production is a highly energy intensive process and improvement of energy efficiency in this process is considered as promising measures for reducing industrial greenhouse gases emissions (GHG). This study focuses the Pakistan's pulp and paper industry which consumes around 7% of the country's industrial energy and contributes to over 317,269 tonnes of CO 2 emissions. With rising demands for fuels and consequently as harp increase in CO 2 emissions due to the growth of the paper sector in Pakistan, this article aims to analyse the energy efficiency and carbon dioxide emissions reductions potential through the incorporation of cogeneration technologies. The cogeneration technologies studied are agas turbine, steam turbine and combined cycle and are evaluated from the energetic and economic point of view to propose a best suitable technology for each paper mill. The proposed cogeneration technologies are selected on the basis of high energy utilisation factor, as implepayback period of five years or less with least Annualised life cycle cost. The result shows that a theoretical energy saving potential equivalent to 16.9% of the actual thermal energy requirement of mills can be achieved through cogeneration which will lead to 14.3% reduction of the present carbon emissions levels in Pakistan's paper sector.

We describe a duo of experimental methods for determining the transverse dimensions of individual wood fibres using 2D optical microscopy and 3D x-ray tomography. These non-invasive optical sectioning methods, in conjunction with segmentation through image analysis, enables in situ identification of individual fibres in a paper sheet. The relationship between local fibre dimensions, i.e. diameter and fibre wall thickness are established for kraft (NBSK) pulp fibres and compared to values obtained from wood. For the first time, we propose a criterion for transverse fibre collapse during the papermaking process that is based on both fibre diameter and wall thickness Canfor Pulp Products Inc., the Natural Sciences and Engineering Research Council

Printing of electronic devices on a paper substrate using 2D graphene-based ink is an opening gate to innovative applications, where devices would be biodegradable, eco-friendly and can be disposed of with negligible impact on the environment. A resistor is a key element of electronic devices and their application area depends upon its power rating and temperature coefficient of resistance (TCR). In this work, in house developed graphene ink is successfully utilized to fabricate a paper-based resistor using a bar coating technique. Dimensional patterning with precise known values of resistance is achieved using a laser with freedom of shape and size which has been explored for the first time on a paper substrate. The resistor has potential to handle ∼7 W power at room temperature with capacity to withstand up to 200 V which is the highest among reported printed resistors. A dual, low and high TCR is observed, correspondingly in cold (173 K to 300 K) and hot (300 K to 373 K) temperature regions with an activation energy Ea of ∼8 meV for the cold region which is 375 percent lower than the hot region (∼30 meV). The dual TCR behaviour is of great importance for application as a stable resistor up to room temperature, and as a thermistor above room temperature.

Aging of transformer paper insulation is commonly investigated through indirect measurements conducted in the oil, e.g. furanic compounds. In addition to the conventional indicators, recent investigations showed that alcohols like methanol and ethanol in oil could be used as paper aging indicators. This paper focuses on the applicability of these new paper aging indicators in a novel, gas-to-liquid (GTL) technology based transformer oil through an accelerated laboratory aging experiment. The experiment was conducted at 120 °C for up to 280 days. A conventional mineral oil was also tested as a reference. Kraft paper aged in both oil types showed similar reductions in degree of polymerization (DP) and tensile strength (TS). Amount of methanol in oil is higher than that of 2-FAL in oil when DP is over 375, confirming the promise of using methanol as an early paper aging indicator. Both the new paper aging indicator, methanol and the conventional paper aging indicator, 2-FAL are applicable for the GTL oil without any modifications. In addition, oil only aging experiments showed that oil does produce methanol but it is negligible compared with oil paper aging experiment; however the amount of ethanol measured in the present oil paper aging experiment is believed to be originated from oil oxidation rather than from paper aging.

Lightweight glass-ceramic from waste material consists of (x) paper ash- (80-x) cullet – 20 Kaolin clay where (10 ≤ x ≤ 30 weight %) are sintered at 900°C, 1000°C and 1100°C using conventional solid-state reaction technique. The influence of composition and sintering temperature on density, crystalline phase, porosity and surface pore morphology was studied. The crystal symmetry, space group and unit cell dimensions which are executed from XRD data are analyzed using SmartLab Studio II Powder XRD software. Meanwhile, the lattice parameter, cell volume, theoretical densities and porosity were estimated by Rietveld refinement method. The results reveal that all parameters exhibit a temperature-dependent character, as the temperature is increased, the density decreases and porosity increases due to bloating effects. It is also found out that the glass-ceramic compose of 25 paper ash −55 cullet-20 Kaolin clay, sintered at 900°C exhibits an optimum characteristic of the sample density reached optimum because of vitrification between cullet glass, paper ash and kaolin clay to form liquid phase which promotes adhesion and polymerization. It is observed that the surface morphology of the sample is affected by the crystallization process during sintering.

Although noble metal nanocatalysts show superior performance to conventional catalysts, they can be problematic when balancing catalytic efficiency and reusability. In order to address this dilemma, we developed a smart paper transformer (s-PAT) to support nanocatalysts, based on easy phase conversion between paper and pulp, for the first time. The pulp phase was used to maintain the high catalytic efficiency of the nanocatalysts and the transformation to paper enabled their high reusability. Herein, as an example of smart paper transformers, a novel chromatography paper-supported Au nanosponge (AuNS/pulp) catalyst was developed through a simple water-based preparation process for the successful reduction of p-nitrophenol to demonstrate the high catalytic efficiency and reusability of the noble metal nanocatalyst/pulp system. The composition, structure, and morphology of the AuNS/pulp catalyst were characterized by XRD, TGA, FE-SEM, ICP, TEM, FT-IR, and XPS. The AuNS/pulp catalyst was transformed into the pulp phase during the catalytic reaction and into the paper phase to recover the catalysts after use. Owing to this smart switching of physical morphology, the AuNS/pulp catalyst was dispersed more evenly in the solution. Therefore, it exhibited excellent catalytic performance for p-nitrophenol reduction. Under optimal conditions, the conversion rate of p-nitrophenol reached nearly 100% within 6 min and the k value of AuNS/pulp (0.0106 s−1) was more than twice that of a traditional chromatography paper-based catalyst (0.0048 s−1). Additionally, it exhibited outstanding reusability and could maintain its high catalytic efficiency even after fifteen recycling runs. Accordingly, the unique phase switching of this smart paper transformer enables Au nanosponge to transform into a highly efficient and cost-effective multifunctional catalyst. The paper transformer can support various nanocatalysts for a wide range of applications, thus providing a new insight into maintaining both high catalytic efficiency and reusability of nanocatalysts in the fields of environmental catalysis and nanomaterials., A smart paper transformer supported nanocatalyst platform is developed based on the facile phase conversion between paper and pulp for both high-efficiency and high-reusability catalysis, with wide applications demonstrated by using Au nanosponge.

Tight assembly of stator windings with no insulation paper damage is a manufacturing challenge. We evaluate different sets of parts according to the following parameters: magnet wire thickness, stator slot smoothness, length of the straight magnet wire after the slot end, and type and amount of insulation cap at the end of the slot. These parameters have discrete values with small differences between them. The damage criterion is the decrease of the insulation paper breakdown voltage after assembly/disassembly of parts, assembled in a small set of designed experiments. Parameter values, i.e., levels at individual experiments are set by an orthogonal experiment matrix. Repetition of each experiment provides statistical significance. Data analysis shows that the additive model alone is not sufficient due to the high correlation of the parameters’ influences. We extend the model to include interparameter influences, which we model by adding a virtual parameter. The extended additive model generates parameter values that do not degrade the insulation paper breakdown voltage within the manufacturing process. These values are verified by repetitions of the control experiment.

Freestanding tin oxide-boron oxide/reduced graphene oxide (SnO$_{2}$-B$_{2}$O$_{3}$/rGO) nanocomposite anode was produced for Li-ion cells. This binder-free flexible paper anode structure was fabricated by combining SnO$_{2}$-B$_{2}$O$_{3}$ composite and graphene oxide which were synthesized through the sol-gel method and Hummers' method, respectively. Field emission gun scanning electron microscopy, high-resolution transmission electron microscopy, energy dispersive X-ray spectrometer, Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray diffraction were utilized to characterize anode materials. The Williamson-Hall (W-H) analysis was applied using XRD data to determine crystal size and strain of the lattice. Electrochemical tests, cyclic voltammetry, and electrochemical impedance spectroscopy measurements were performed to determine electrochemical properties of the anodes. The results indicated that the anode formed with SnO$_{2}$-B$_{2}$O$_{3\, }$particles anchored on the rGO layers provided higher discharge capacity (838 mAh g$^{-1})$ than that of SnO$_{2}$/rGO (395 mAh g$^{-1})$ after 100 cycles. The electron-deficient nature of boron supplied an effective increase in electrochemical energy storage performance.

The open-source release of self-replicating rapid prototypers (RepRaps) has created a rich opportunity for low-cost distributed digital fabrication of complex 3-D objects such as scientific equipment. For example, 3-D printable reactionware devices offer the opportunity to combine open hardware microfluidic handling with lab-on-a-chip reactionware to radically reduce costs and increase the number and complexity of microfluidic applications. To further drive down the cost while improving the performance of lab-on-a-chip paper-based microfluidic prototyping, this study reports on the development of a RepRap upgrade capable of converting a Prusa Mendel RepRap into a wax 3-D printer for paper-based microfluidic applications. An open-source hardware approach is used to demonstrate a 3-D printable upgrade for the 3-D printer, which combines a heated syringe pump with the RepRap/Arduino 3-D control. The bill of materials, designs, basic assembly, and use instructions are provided, along with a completely free and open-source software tool chain. The open-source hardware device described here accelerates the potential of the nascent field of electrochemical detection combined with paper-based microfluidics by dropping the marginal cost of prototyping to nearly zero while accelerating the turnover between paper-based microfluidic designs.

The current research aimed to increase the calorific value of woody cutting waste briquette with paper waste pulp as binder. There were three different binder variation used in this study, they are 5 %, 10 %, and 15 %. To create a briquette, a cylindrical iron mold with diameter of 3.5 cm and height of 3 cm and a hydraulic press with 2 t power were applied. The physical characteristics of the combination woody waste briquette and paper waste pulp, such as moisture content, ash content, volatile matter and carbon fix were examined using proximate analysis. The calorific value of briquetted fuel was tested by bomb calorimeter. The combustion test was performed to determine the combustion characteristic of briquettes, for example initial ignition time, temperature distribution, and combustion process duration. The general result shows that the calorific value of briquette stood in the range of 4 876 kCal kg–1 to 4 993 kCal kg–1. The maximum moisture content of briquette was 5.32 %. The longest burning time was 105 min.

At present, the insulation performances of electrical apparatus under lightning impulse voltages are always evaluated by the withstand test of standard lightning impulse voltage (1.2/50 µs), which is recommended by IEC Standard. However, the actual time parameters of transformer invading lightning impulse voltage present an obvious dispersibility characteristics. The standard wave shape is only representative of one particular class of lightning waves, which is far from satisfactory to act as the guidance waveform in the design of power equipment insulation. On the basis of the above research background, the relationship between breakdown characteristics of oil paper insulation and time parameters of applied lightning impulse voltage was investigated in this study. The 50% breakdown voltage characteristics of oil paper insulation under lightning impulse voltage with different time parameters were determined. The test results indicate that a short wave front time could lead to relatively low 50% breakdown voltage, while when the wave tail time varied, the 50% breakdown voltage of oil paper insulation barely changed. At last the simulation model of oil paper insulation was developed, and the current flowing through the oil paper insulating system under lightning impulse voltage was calculated. On the basis of the simulating results, the relationship between current and time parameters was analysed.