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Thin coating layers of cross-linked polydimethylsiloxane (PDMS) and inorganic particles including glass spheres (GS), colloidal and fumed silica (aero and N20), montmorillonite (MMT), and kaolin (K) were attached onto Grade 1 Whatman filter paper (WFP) substrates using the spraycoating procedure to achieve superhydrophobic hybrid paper sheets. Coating formulations were varied in terms of their PDMS molecular masses and inorganic particles to prepare different samples. The effect of PDMS molecular weight and change in inorganic particle composition on the optical properties, surface roughness, barrier properties, surface chemistry, and topography was investigated. Hybrid paper sheets with ΔE00 values lower than 1 could be achieved, the surface roughness of which could be decreased by increasing the PDMS molecular weight in the coating formulation. Scanning electron microscopy studies revealed a homogeneous coating distribution, resulting in significant improvements in both the air and water barrier properties of the hybrid paper sheets. Spectroscopic investigations revealed the presence of interactions between the coating layer and the underlying paper substrate. Moreover, the distribution behavior of the inorganic particles on the spraycoated surfaces using the proposed method was also investigated using model compounds. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to find a suitable solution to treat the solidification paper by using hydroxypropyl cellulose (HPC) to improve the mechanical, physical and chemical properties of paper. Design/methodology/approach: The samples have gone several stages, starting with the manufacture of paper from the linen pulp and the same components of the hardened manuscript papers. It was subjected to artificial aging to reach an age comparable to the manuscript age, then it was subjected to natural aging by inoculation it with A. niger. Mechanical cleaning of the leaves was done with soft brushes. The samples have been consolidated by HPC 2%. Digital microscopy, scanning electron microscopy, mechanical properties measurement, color change, Fourier transform infrared and pH measurements were used to assess the effect of HPC on the qualities of leaves. Findings: HPC succussed in strengthening and restoring the natural, chemical and mechanical properties for the solidified leaves. Originality/value: The solidified papers phenomenon constitutes severe suffering for manuscripts and books conservators. The paper consolidation initial stage is one of the most important conservation stages because paper has lost many natural, mechanical and chemical properties. The most important feature of this study is providing a solution to the hardened leaves strengthening problem and restoring their chemical, natural and mechanical properties. [ABSTRACT FROM AUTHOR]

Most methodologies to measure the moisture‐induced deformation (hygro‐expansion) of paper microconstituents, including fibres and interfibre bonds, are low resolution or time‐consuming. Hence, here, a novel method is proposed and validated to measure high‐resolution full‐field strain maps of paper microconstituents during hygro‐expansion, based on environmental scanning electron microscopy (ESEM). To this end, a novel climate stage enables accurate control of the relative humidity (RH) near the specimen in the ESEM from 0%–100%. The fibre surface, which is decorated a priori with a microparticle pattern, is captured during RH change. Subsequently, correlating the fibre surface using a dedicated global digital image correlation algorithm enables high‐resolution hygro‐expansion strain maps. Method optimisation involved performing contrast enhancement, scan‐correction to reduce ESEM artefacts and a background correction, resulting in a strain resolution of 6·10−4. Method validation revealed that the fibres' crystallinity is affected by the electron beam, even for minimal invasive electron beam settings. Interestingly, however, the fibres consistently exhibit conventional hygro‐expansion behaviour during the drying slopes. Using the optimised procedure, hygro‐expansion characterisation of two interfibre bonds and four interfibre bond cross‐sections revealed the competition between the low longitudinal and large transverse fibre hygro‐expansion in the bonded area. [ABSTRACT FROM AUTHOR]

Purpose: Paper aims to determinate caking paper manuscript cause through studying of the manuscript components, bio-deterioration and physio-chemical deterioration factor. It will facilitate manuscripts and paper conservators to understand paper blocking and caking phenomenon. Design/methodology/approach: The manuscript condition has been diagnosed by focusing on adhesion and fossilization regions. To achieve this, some methods of analysis and examination were used, such as visual examination, digital microscopy and scanning electron microscope were used to studying surface changes. X-ray diffraction and Fourier transform infrared microscopy were used to determinate of cellulose crystallinity, ink composition and identify the binding medium. Findings: The results revealed the use of cotton pulp, and calcium carbonate was among the fillers that were used to improve the properties of paper. The crystallization of cellulose was lower in the first and last papers than the papers located in the heart of the manuscript. The most important reasons that led to the papers caking was the presence of fungi A. niger, Cladosporium sp, Chaetomium sp, by secreting some enzymes in combination with some other factors such as difference variation in temperature and moisture. Originality/value: All deterioration factors participate with each other until rule the damage circle of the papers because one factor alone cannot stick the papers. It was inferred from the examinations and analyzes that were conducted for the samples. [ABSTRACT FROM AUTHOR]

Biological degradation of documentary heritage is a serious issue faced by libraries, museums and archives as it can lead to paper becoming brittle, fragile and discoloured, resulting in a loss of information. This study investigates the impact of didecyldimethylammonium bromide (DDAB) on the properties of pure or inked paper and the growth of different types of fungi. Three fungi species known for their ability to cause paper biodete-rioration in libraries and museums, Aspergillus clavatus Desm, Penicil-lium paneum Frisvald and Ulocladium chartarum Preuss, were selected for the DDAB salt antifungal activity test. The study measured the pH and degree of polymerization (DP), monitored colour changes and conducted scanning electron microscopy analyses (SEM) to confirm that DDAB can be used as a biocide for fungi on pure or inked paper. The study also investigated the antifungal effect of DDAB on paper treated with different types of ink, including black (iron-gall ink) and brown (copper ink). Didecyldi-methylammonium bromide (DDAB) can be used as a biocide for cleaning and preserving paper documents, with active concentrations of 0.7 and 1%. [ABSTRACT FROM AUTHOR]

Cellulose microspheres (CMS) are a type of spherical regenerated cellulose particles with versatile properties which have been used as carrier materials in medical and technical applications. The integration of CMS into paper products opens up novel application scenarios for paper products in a wide range of fields. However, the incorporation of CMS carriers into paper products is challenging and hitherto no reports do exist in literature. Here, we present a feasibility study to incorporate up to 50 w.% CMS in paper hand sheets using retention aids. Our primary observations highlight the successful formation of uniform paper hand sheets retaining its tensile strengths at elevated CMS concentrations. Sheets with high CMS contents exhibit an increase in density and display enhanced surface smoothness — an outcome of a CMS layer forming atop the fiber base — which effectively bridges voids and rectifies surface irregularities as supported by Gurley testing, infinite focus microscopy and scanning electron microscopy. While our primary objective centered on the general feasibility to manufacture CMS-containing papers, the resulting composite scaffold carries significant potential as a platform for innovative, functional paper-based materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Here, we use a variety of microscopic imaging techniques, including scanning electron microscopy, 3D visible light microscopy, and portable microscopy to capture the topography of rough paper. Paper coated with a model soot was cleaned with either a firm vinyl eraser or softer, putty-like kneaded eraser and reimaged to characterize the disposition of remaining soot. Although both methods remove soot from the upper-most surface of the paper, only the kneaded eraser can conform to the complex topography to remove soot from the interstices between paper fibers. [ABSTRACT FROM AUTHOR]

An important step in the conservation of old paper documents is the analysis of both the medium and the ink, in an attempt first to determine the extent of deterioration and degradation and then to choose the best preservation and restoration solutions. Our paper focuses on the analysis of three old documents displayed at the 'Poni-Cernătescu' Museum in Iaşi City, Romania by optical microscopy (OM), scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDX), micro-FTIR spectroscopy and FT-Raman. Thus, the morphology and chemical composition of the paper media and the type of ink, as well as the cellulose crystallinity index were determined. PCA (Principal Component Analysis) was also used while relying on spectra collected by FTIR spectroscopy. We were able to determine the extent of degradation of the documents by corroborating all these findings. [ABSTRACT FROM AUTHOR]

Surface hydrophobicity and grease resistance of paper may be achieved by the application of coatings usually derived from fossil-oil resources. However, poor recyclability and environmental concerns on generated waste has increased interest in the study of alternative paper coatings. This work focuses on the study of the performances offered by two different biopolymers, poly(3-hydroxybutyrate-co-3hydroxyvalerate) (PHBV) and polycaprolactone (PCL), also assessing the effect of a plasticizer (PEG) when used as paper coatings. The coated samples were characterized for the structural (by scanning electron microscopy, SEM), diffusive (water vapor and grease barrier properties), and surface properties (affinity for water and oil, by contact angle measurements). Samples of polyethylene-coated and fluorinated paper were used as commercial reference. WVTR of coated samples generally decreased and PHBV and PCL coatings with PEG at 20% showed interesting low wettability, as inferred from the water contact angles. Samples coated with PCL also showed increased grease resistance in comparison with plain paper. This work, within the limits of its lab-scale, offers interesting insights for future research lines toward the development of cellulose-based food contact materials that are fully recyclable and compostable. [ABSTRACT FROM AUTHOR]

With the aim of exploring an alternative method of nano-doping in cellulose paper and improving flashover strength of oil-impregnated paper, radio frequency (RF) magnetron sputtering method is introduced into the structural modification of insulating paper for converter transformers. In this experiment, insulating paper was treated with ZnO sputtering for 0, 7.5, 15 and 30 min, respectively. The surface morphology of dry paper was observed with a scanning electron microscope. The bonding mode of sputtered ZnO particles with cellulose matrix was investigated via attenuated total reflection infrared (ATR-IR) spectroscopy and mechanical property of the sputtered samples were studied. Surface and volume conductivities of the oil-impregnated sputtered paper were measured. Moreover, the charge dissipation characteristics of sputtered insulating paper was investigated by means of surface potential decay. In addition, trap distribution and carrier mobility of specimen were further obtained. Finally, the DC flashover strength were tested. The results showed that ZnO magnetron sputtering had a distinct influence on the structure of the insulating paper, resulting in the formation of hydrogen bond and chemical bond and an increase of the surface and volume conductivities. ZnO sputtering was found to decrease the initial potential and accelerate charge decay. Moreover, appropriate sputtering enhanced the surface flashover strength.

Abstract Here we describe a screen-printed supercapacitor produced onto filter paper using poly (3, 4-ethylene dioxythiophene)-poly (styrene sulfonate) (PEDOT:PSS)/multiwall carbon nanotube (MWCNT) composite as active materials. We use a gel-like electrolyte based on poly (vinyl alcohol) and phosphoric acid (PVA/H 3 PO 4), serving as both an ionic conductor and as an electrode separator. The electrodes are physically characterized through micro-Raman scattering analyses, sheet resistance measurements as a function of the printed number of layers and through scanning electron microscopy. The supercapacitor performance is investigated through impedance spectroscopy, equivalent circuit fitting, cyclic voltammetry (CV), long-term cycle stability and galvanostatic charge/discharge. The electrodes exhibit a low sheet resistance, reaching 17 Ω sq−1, being suitable for use as both electrode and the current collector. The supercapacitor shows good capability behavior over impedance spectroscopy and CV measurements, and 72% of capacitance retention after 1000 cycles. We find a maximum specific capacitance of 20,3 F g−1 for a charge/discharge current of 1 mA, and equivalent series resistance of 60 Ω, leading to energy and power densities of 3,1 Wh kg−1 and 420 W kg−1, respectively. In conclusion, we describe here a flexible supercapacitor without metal collectors produced by a simple printing method. Highlights • A paper based supercapacitor was prepared using screen-printed electrodes. • Screen-printed PEDOT:PSS/MWCNT on paper exhibited a sheet resistance of 17 Ω sq.−1. • The paper-based supercapacitor exhibited a specific capacitance of 20,3 F g−1. [ABSTRACT FROM AUTHOR]

A 3-dimensional carbonized multi-walled carbon nanotube (MWCNT) paper was used as the host of nano-tin oxide (SnO2) for lithium-ion batteries (LIBs). The cellulose fibers were fully mixed with MWCNTs in water. Then, the paper was obtained via vacuum filtration. Carbonization was carried out in a vacuum furnace at 1460°C. SnO2 slurry was coated on the carbonized MWCNT paper (CMP). Scanning electron microscopy (SEM) was utilized to observe the anode electrode. The images of SEM indicated that the nano-SnO2 was embedded into the holes of the porous CMP collector. This contributed the increase of contact interface area of the nano-SnO2 and the collector and the significantly reduced interface resistance. Electrochemical tests showed that the initial discharge capacity reached 1745 mAh g−1 with a coulumbic efficiency (CE) of 70.39% at a current density of 50 mA g−1. The composite electrode still maintained a reversible capacity of 753 mAh g−1 with a CE of 98% at a current density of 200 mA g−1 after 100 cycles. These marvelous composite electrodes exhibited a promising future for the next generation of LIBs. [ABSTRACT FROM AUTHOR]

The cost of specialized scientific equipment can be high and with limited funding resources, researchers and students are often unable to access or purchase the ideal equipment for their projects. In the fields of materials science and mechanical engineering, fundamental equipment such as tensile testing devices can cost tens to hundreds of thousands of dollars. While a research lab often has access to a large-scale testing machine suitable for conventional samples, loading devices for meso- and micro-scale samples for in-situ testing with the myriad of microscopy tools are often hard to source and cost prohibitive. Open-source software has allowed for great strides in the reduction of costs associated with software development and open-source hardware and additive manufacturing have the potential to similarly reduce the costs of scientific equipment and increase the accessibility of scientific research. To investigate the feasibility of open-source hardware, a micro-tensile tester was designed with a freely accessible computer-aided design package and manufactured with a desktop 3D-printer and off-the-shelf components. To our knowledge this is one of the first demonstrations of a tensile tester with additively manufactured components for scientific research. The capabilities of the tensile tester were demonstrated by investigating the mechanical properties of Graphene Oxide (GO) paper and thin films. A 3D printed tensile tester was successfully used in conjunction with an atomic force microscope to provide one of the first quantitative measurements of GO thin film buckling under compression. The tensile tester was also used in conjunction with an atomic force microscope to observe the change in surface topology of a GO paper in response to increasing tensile strain. No significant change in surface topology was observed in contrast to prior hypotheses from the literature. Based on this result obtained with the new open source tensile stage we propose an alternative hypothesis we term ‘superlamellae consolidation’ to explain the initial deformation of GO paper. The additively manufactured tensile tester tested represents cost savings of >99% compared to commercial solutions in its class and offers simple customization. However, continued development is needed for the tensile tester presented here to approach the technical specifications achievable with commercial solutions. [ABSTRACT FROM AUTHOR]

There is current interest in using agro-based biopolymers in industrial applications. Because cottonseed protein is abundantly available, it would be useful to explore its feasibility as a polymeric additive and possible substitute for petroleum-based materials. In this work, we studied cottonseed protein isolate as a paper additive and observed its effects on the paper’s dry and wet strength. The tensile strength of paper was found to vary with the amount of the protein applied. By application of an 11% protein solution to the paper, the dry and wet strength increased by 33 and 16% compared with the paper by itself, respectively. The combined use of cottonseed protein and an acid (acetic, adipic, aspartic, and citric acids) to promote adhesion resulted in even greater dry paper strength but not in greater wet paper strength. Thermogravimetric analysis, infrared spectroscopy, and scanning electron microscopic studies suggested that the protein interacted with acid and that both components interacted with paper fibers to produce increased strength. [ABSTRACT FROM AUTHOR]

A binder-free and flexible Au electrode is prepared by spontaneous deposition of Au onto a A4 (A4-paper)-8B (8B pencil)-Ni Film substrate (ABNi) which is assembled by electrodeposition of nanoscale Ni particles on the surface of A4 paper coated by 8B pencil. The morphology and phase structure of the (A4-paper)-8B (8B pencil)-Ni Film-Au (ABNiAu) electrode are characterized by scanning electron microscopy equipped with energy dispersive X-ray spectrometer and X-ray diffractometer. The catalytic activity of the ABNiAu electrode for NaBH 4 electrooxidation is investigated by means of cyclic voltammetry and chronoamperometry. The electrode exhibits a high electric conductivity and the activity substance attaches to the surface of paper substrate tightly and does not fall off at all and the nanoscale Ni and Ni Au alloy enhance the broken of the B H bond in the BH 4 − , all of which lead to a high catalytic activity for NaBH 4 electrooxidation. The oxidation current density reaches 300 mA cm −2 in 1 mol dm −3 NaOH and 0.1 mol dm −3 NaBH 4 at −0.2 V. The exchanged electrons (n) is 6.0 (8.0 in theory), which indicates that the ABNiAu electrode has much higher utilization efficiency of the fuel than our reported LaNi 5 /Pd (n = 4) electrode. [ABSTRACT FROM AUTHOR]

Thin film microextraction (TFME), which is based on the retention of target analytes in a thin polymeric coating, is a powerful sample treatment technique with multiple applications. This article describes an easy and cheap procedure to synthesize polystyrene membranes which can be used as sorptive phases in TFME. The polymeric film is formed by the simple deposition of a thin polymeric layer over a conventional laboratory paper that acts as inert support. The synthesis has been studied and the resulting material has been characterized by infrared spectroscopy and scanning electron microscopy. The thin film has been analytically evaluated using the determination of methadone in urine samples by gas chromatography/mass spectrometry (GC/MS) as proof of concept problem. A pipette tip manifold, that allows the confinement of the film while permits the sample and solvents handling, has been designed for the extraction. The developed method provides a good linearity (R 2 = 0.9986) and sensitivity (limit of quantification of 10 μg/L), especially if the low sample volume (200 μL) used is considered. The precision (relative standard deviation better than 14%) and relative recovery values (average value of 106% for five independent samples) demonstrated the potential of the approach. [ABSTRACT FROM AUTHOR]

Silver-clay nanohybrids based on silver nanoparticles (AgNPs) with montmorillonit (MMT) and milled MMT, shortly AgMMTnano and AgMMTmilled, have been prepared to improve the performance of antibacterial properties of paper. The results obtained by dynamic light scattering indicated the presence of silver particles in the nanometer range, which have a great accumulation tendency. The results of AAS and ICP-AES tests showed that nanosilver amount in the AgMMTmilled was doubled compared to the AgMMTnano, but according to the EDX results, the amount of nanosilver in paper treated with the former was less than in the latter. FE-SEM images showed that the dimensions of deposited nanosilver on the surface of clay were smaller than in case of AgNPs alone. Papers treated with nanohybrids had better antibacterial properties compared to that prepared by naked nanosilver. It was also found that the antibacterial property of papers treated with AgMMTnano were more stable during three-stage tests compared to those with AgMMTmilled. Nanohybrids with Ag conc. more than 15 ppm, especially hybrids with Ag conc. of 50 ppm, result in a significant improvement in antibacterial properties of paper. It can be concluded that silver-clay nanohybrid with a 25-ppm concentration of nanosilver could be the best and most economic antibacterial component. [ABSTRACT FROM AUTHOR]

Volumes from an archive of the University of Milan showed whitish-grey discolouration putatively caused by microorganisms. Microscopic and viability assays proved that discolouration from two volumes were characterized by a marked presence of viable fungi, demonstrating that they were mainly biological in nature. Fungal sequences were phylogenetically most closely related to Eurotium , Aspergillus , Candida , Penicillium , Alternaria , Phaeosphaeria , Capnodiales and Pleosporales taxa. SEM analysis showed that Eurotium halophilicum is dominant on the two infected volumes. Viable airborne fungal loads near the two volumes were higher than recommended maximum values, demonstrating that airborne fungi could represent a source of risk. The airborne microbial community sampled in two different seasons was composed by fungi belonging in the genera Aspergillus , Candida and Eurotium . The detection of E. halophilicum also in the archival air indicated a possible source of contamination. Fluctuations of thermo-hygrometric values were also observed in the archive in the different seasons. The occurrence of white efflorescence on the stored volumes most likely depended on the lack of both a dusting programme and air-conditioning, and insufficient ventilation in the repository, and, on the hygroscopic behaviour of the binding materials used in the manufacture of the volumes. [ABSTRACT FROM AUTHOR]

Many manuscripts and historical books contain a form of deterioration known as foxing or fox spots, a brownish stain which has the effect of altering aesthetic and visual appeal The aim of this work is to study the role of the extracts of Water Cantaloupe (CE) and Water melon (WE) separately as natural products in removing foxing spots in various modern and old papers. Old papers and three types of modern papers made from cotton, linen and a mixture of cotton, linen and wood (1:1:1) were used fo r this purpose. Each type was divided into two groups, one of them was infected with foxing and the other was left as control (uninfected). Infected papers were treated with CE, WE and 2% sodium hypochlorite (as a traditional chemical bleaching) separately. Fourier Transform Infrared Spectroscopy (FT1R), Atomic Absorption Spectroscopy, Scanning Electron Microscopy equipped with Energy-Dispersive X-ray spectroscopy (SEM-EDX) in addition to some optical and mechanical properties were carried out to evaluate the Cantaloupe Extracts (CE) and Water Melon Extracts (WE) use in removing foxing stains compared to sodium hypochlorite. The results showed that CE removed foxing in different studied papers at pH = 7.4. In contrast, WE could not remove these foxing at any studied pH values. [ABSTRACT FROM AUTHOR]

Hybrid material based on halloysite nanotubes (HNTs) and sodium perfluorooctanoate (NaPF8) was used as a consolidant for paper treatment. The consolidation efficiency was determined by thermogravimetry as well as by paper grammage determination. Morphological analysis of the treated paper was performed by means of scanning electron microscopy while the effect of modified HNTs on the thermal behaviour of the cellulose fibres was investigated by differential scanning calorimetry which determined the combustion enthalpy of the paper.Water contact angle measurements were performed to study the paper wettability. The physico-chemical properties investigated (mesoscopic structure, thermal stability and wettability) of the treated paper were correlated successfully with the consolidation loading and, consequently, to the affinity between the fluorinated modified HNTs and the fibrous cellulose structure. This study proposes a new green protocol for paper consolidation based on natural tubular nanoparticles with a flame retardant effect. [ABSTRACT FROM AUTHOR]

Pyrolysis volatiles and the environmental impact of printing paper, newspaper, and silk were investigated to identify suitable materials for heat-induced eco-printing (HIEP) using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). Furthermore, the printing effects of simulated HIEP and the material microstructures were studied using scanning electron microscopy (SEM). The results indicated that the toxicity of pyrolysis volatiles is highest for newspaper, followed by silk and then printing paper, whereas environmental friendliness follows the opposite trend. A high concentration of lignin, the basic structural element of which is phenyl propane, and the presence of halogens in the newspaper led to the generation of more toxic substances during the pyrolysis process. The benzene compounds and heterocyclic compounds in silk also produced high levels of toxic substances. Based on these findings and the higher color permeability of newspaper, printing paper was the most suitable material for HIEP and newspaper was the least suitable. Additionally, silk may still be used in HIEP in small amounts for the production of art, name cards, and clothing tags. [ABSTRACT FROM PUBLISHER]

Nano-structured graphene oxide (GO) freestanding paper was synthesized by an arc recharge technique in flowing of oxygen for the first time. This technique offers new ways on how e.g. layers structure nanomaterials could be produced. The morphology and structural properties of the as-synthesized GO were examined by means of X-ray diffraction, Fourier transform infrared spectra, scanning electrom microscopy, energy dispersive x-ray spectroscopy, transmission electron microscopy, high resolution transmission electron microscopy and selective area electron diffraction techniques. The structural and morphological characterizations revealed that the synthesized GO were well-defined nanosheets with a thickness of 6 nm. The optical band gap was calculated from the absorption spectrum, and was found to be 3.32 eV. Furthermore, we aim to use GO paper to develop new electromagnetic interference shielding sheets that have a high shielding effectiveness (SE) (over 30 dB) at frequencies in the 1-12 GHz range. The complex permittivity and total shielding effectiveness of as synthesized GO freestanding paper are measured at frequencies from 1 to 12 GHz. Finally, to enhance the performances of the electromagnetic shields effectiveness, five-layered GO sheets were made. Furthermore, the highest SE for the light-weight freestanding GO paper was 50 dB at 1 GHz, indicating commercial use for many industrial or military shielding applications as an attractive candidate for the new type of microwave shielding. [ABSTRACT FROM AUTHOR]

A systematic experimental study applying nanosecond laser pulses with 532 nm radiation to a specially selected set of historical paper samples exhibiting a broad range of composition and origin was undertaken to develop a quantitative irradiation dose model. This allows the optimisation of laser pulse number and fluence in order to maximise cleaning efficiency while excluding substrate modifications such as yellowing or destruction. [ABSTRACT FROM AUTHOR]

There has been a growing interest in laser cleaning applications for a variety of organic materials such as paper, parchment, textiles, and leather during the last decade. However, archaeological organic materials, notably papyrus, have rarely been investigated. This contribution examines whether removal of burial encrustation can be justified in view of its short-term and long-term effects on the substrate. To examine this, tests using mock objects have been performed. Using artificially soiled and archaeological papyrus samples, optimization of laser cleaning parameters using a picosecond laser (1064 nm, various operating conditions) was attempted. Optimization was based on colorimetry, optical microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, and cellulose degree of polymerization data, both before and after accelerated degradation. In papyrus, there is no clear damage threshold, and substrate degradation can always be observed and is comparable in treated (cleaned) and untreated (soiled) objects. Therefore, the decision on whether to clean papyrus using lasers is predominantly based on aesthetic and treatability (e.g. need for consolidation) criteria. [ABSTRACT FROM AUTHOR]

Nanoparticles of calcium oxide (100 nm), prepared using the sol-gel citrate method, were sonicated for 20 min in water and used for paper deacidification treatment via the Barrow method. For comparison, deacidification was also performed using bulky calcium hydroxide. Also tested as reagents, were mixtures of the two previously mentioned reagents with the addition of 0.1% gelatin, as well as Bookkeeper alkali material. After thermal accelerated aging at 90 °C for 512 h, all paper samples were investigated by scanning electron microscopy (SEM), infrared (FTIR) and absorbance (UV/Vis) spectroscopy. pH, alkaline reserve (AR), paper sorption and strength properties were determined. The highest value of AR and pH was provided by the calcium nanoparticles treated with gelatin. After artificial aging, the gelatin-treated bulky, nano-sized calcium hydroxide and Bookkeeper alkali material demonstrated an equal decrease in AR and pH. Added gelatin increased the binding of alkali material to paper. Also, measurement of paper strength showed that gelatin treated paper even after aging can resist higher force before breaking. At the same time addition of 0.1% of gelatin did not change paper sorption properties. FTIR and UV/Vis spectra analysis after the artificial aging process confirmed the positive effect of nano-sized calcium hydroxide. [ABSTRACT FROM AUTHOR]

The capacity of Ag nanoparticles to destroy various micro‐organisms makes it one of the most powerful antimicrobial agents, an attractive feature against antibiotic resistant bacteria. Here, a simple method to develop coating of colloidal silver on paper using a biological method is presented. The coated paper was studied by scanning electron microscopy, X‐ray diffraction technique and atomic absorption spectroscopy. The antibacterial activity of the coated paper against Escherichia coli and Staphylococcus aureus was measured by agar diffusion method. This study shows the potential use of the coated paper as a food antimicrobial packing material for longer shelf life. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to increase the thermal resistance of a cellulose substrate, using films (a mixture of corundum-phase aluminum oxide, α-Al2O3, and a PVA solution). The corundum phase, which was chosen due to its high thermal resistance, was obtained using an adaptation of Pechini‘s polymeric precursor method. A polyvinyl alcohol (PVA) solution was used as a medium for mixing the oxide for subsequent deposition on a paper substrate. The materials were characterized by X-ray diffraction (XRD) and field emission gun scanning electron microscopy (FEG-SEM) coupled with energy dispersive X-ray spectrometry (EDS). The thermal behavior of the material was investigated by thermogravimetry (TG) and differential scanning calorimetry (DSC). The EDS results indicate that all the samples with deposited α-phase aluminum oxide contain the chemical elements (Al and O) originating from the α-phase, while the surface analysis indicated that the paper substrates were completely coated with the films. The TG and DSC analyses of the thermal resistance of the film-coated substrate indicate that it was impossible to increase the thermal resistance of the paper substrate because the events that occurred (decomposition of cellulose and pyrolysis of lignin, hemicellulose and PVA) took place in the same temperature range, as has been reported in the literature for samples of the paper substrate without deposited film. [Copyright &y& Elsevier]

In this study, perennial fast growth Napier grass fibers were used for pulp and papermaking. Chlorination and alkaline processes were carried out using sodium chlorite and sodium hydroxide respectively, for pulp extraction from Napier grass. Detailed chemical composition analysis of the Napier grass fibers and the extracted pulp was carried out and a comparison with other perennial grasses was made. The extracted fibers and pulp obtained from Napier grass were characterized using scanning electron microscopy and Fourier transform infrared spectroscopy. The physical, optical, and mechanical properties of Napier grass pulp handmade paper sheets produced in the laboratory were investigated by finding the opacity, brightness, tensile index, breaking length, and burst index. Handmade paper sheets made from Napier grass pulp were compared to paper made from other perennial grasses. The superior properties of paper produced from Napier grass pulp indicate the suitability of Napier grass as an alternative non-wood source for papermaking. [ABSTRACT FROM AUTHOR]

This research evaluates the use of microblasting technique with powdered cellulose as a new tool for dry cleaning documents. Different cleaning tests were conducted on three documents with different properties following this new approach and the results were compared to those obtained with traditional dry cleaning with erasers. In order to assess changes caused to the supports, the treated documents were examined both before and after cleaning with optical and 3D stereomicroscopy, SEM-EDS and spectrophotometry. The results allow the conclusion that microblasting with powdered cellulose is a feasible technique to remove surface dirt or grime on paper documents. This research proves that the new use of the technique does not entail changes to the surface properties of the treated supports. Moreover, powdered cellulose is chemically stable and compatible with paper documents, preventing negative long-term effects derived from the presence of rubber residues that may remain in paper fibres when using erasers in dry cleaning treatments. [ABSTRACT FROM AUTHOR]

Highlights: [•] In this study we prepare Ag-NPs and Ag @ TiO2 composites as antibacterial nanomaterials. [•] Paper coated by PS nanocomposites containing Ag-NPs and Ag @ TiO2 composites. [•] We conclude that the prepared paper sheet characterize by SEM, EDAX and mechanical properties was evaluated. [•] Paper sheet coated by PS nanocomposites exhibited antimicrobial effect. [•] These Paper sheet can be used as food packaging materials. [ABSTRACT FROM AUTHOR]

Micro-samples of loose dust, paper and paper from areas of pages with accumulated dust were obtained from a collection that was on open display in an historic library with significant levels of particulate pollution. The present study examines the origin of these dust particles and their ingress into the library books. The samples were analysed using scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). Qualitative point SEM-EDS was used to identify the characteristics and origins of individual particles, while bulk analysis was achieved by rastering the electron beam over whole samples. The inorganic fraction of the dust comprised 30–40% calcium sulfate, 10–20% sodium chloride and around 50% silicon dioxide, aluminosilicates, iron oxides/hydroxides and calcium carbonate. The ratios of these components were variously maintained as the dust penetrated between the pages of the book, suggesting that in some books sodium chloride moved as a solid, and not in a solution. This preliminary study suggests that SEM-EDS is a useful tool, not only in the determination of the identities of dust particles and their origin, but also in estimating the relative amounts of dust species and the extent to which they have moved into the book. [ABSTRACT FROM AUTHOR]

Nowadays, effect pigments are widely used in many printing industries. The colorful effects produced by light scattering of these types of pigments add an additional value to the prints and enhances the overall quality of color appearance. The aim of this study was to investigate the quality enhancement of printed specialty papers with various effect pigments in combination with offset inks. Four different effect pigments were used (one luster pigment-EP1, two interference pigments-EP2, EP3, and one multicolor pigment-EP4) as well as two types of paper substrates (film synthetic paper and wood-free paper). The effect pigments were overprinted on dried CMYK offset prints on both paper substrates. The following analysis were performed: scanning electron microscopy analysis of effect pigment particles, contact angles of papers and offset prints, Fourier transform infrared spectrocopy (FTIR), principal components analysis (principal components analysis (PCA)), and flop index analysis of overprinted effect pigments, and paper and print gloss. The results of the experiment indicate that effect pigments behaved differently on different printing substrates. From the FTIR and PCA, it was found that the different composition of effect pigments differently influence the behavior of these particles on the final prints. Effect pigments overprinted on offset CMYK inks on both paper substrates enhance print gloss, except interference pigment EP2 on film synthetic paper. It was also found that the ink color has the most pronounced influence on flop index, followed by the papertype and the type of effect pigment. Higher flop index was obtained at wood-free paper, especially by overprinted pigment EP2. © 2012 Wiley Periodicals, Inc. Col Res Appl, 38, 168-176, 2013. [ABSTRACT FROM AUTHOR]

Abstract: An alternative, new approach to improve the hydrophobicity and barrier properties of paper was evaluated by radio-frequency (RF) plasma octamethylcyclotetrasiloxane (OMCTSO) vapor treatment. The interaction between OMCTSO and paper, causing the increased hydophobicity, is likely through covalent bonding. The deposited thin silicone-like polymeric layer from OMCTSO plasma treatment possessed desirable hydrophobic properties. The SEM micrographs showed uniformly distributed grainy particles with various shapes on the paper surface. Deposition of the silicone polymer-like layer with the plasma treatment affects the distribution of voids in the network structure and increases the barrier against water intake and air. The water absorptivity was reduced by 44% for the OMCTSO plasma treated sheet. The highest resistance to air flow was an approximately 41% lower air permeability than virgin paper. [Copyright &y& Elsevier]

Conductive polymers have been studied extensively because of their attractive physical properties, such as conductivity, luminescent performance, and dielectric property. Poly(3,4-ethylenedioxythiophene) (PEDOT) is one of the most employed conductive polymers for applications, such as a buffer layer of organic electroluminescent devices, due to its high conductivity and electrical stability. In this study, we fabricated a conductive paper coated with PEDOT by direct polymerization onto a paper sheet. The conductive paper exhibited the electrical conductivity of 1.8 S/cm. Scanning electron microscopy images of the conductive paper showed two structures: thin polymer membranes attached to cellulose fibers at the surfaces, and thick polymer sheets extended through the void spaces between the fibers in the inner layers. Consequently, strong interactions between the PEDOT and the cellulose fibers enhanced mechanical properties of the conductive paper. Electron probe X-ray microanalysis (EPMA) revealed distribution elemental maps of carbon, oxygen, sulfur, chlorine, and iron on the conductive paper. [ABSTRACT FROM AUTHOR]

In this study, a suitable method is reported to produce reinforced antibacterial paper packaging using the antimicrobial triclosan (TC) and organically modified montmorillonite (OMMT) as 'model' compounds. Direct incorporation of TC at a concentration of 1 wt% and OMMT at concentrations of 1, 4, 7, and 10 wt% into papers was performed via coating process, and the resulting materials were characterized by in vitro antimicrobial assays, thermogravimetric analysis, scanning electron microscopy, mechanical tests, and water vapor transmission rate determinations. It was demonstrated that the presence of 1% TC in the coated papers exhibited inhibitory effects against Staphylococcus aureus and Escherichia coli. It was also pointed out that increases of approximately 30% in the tensile strength of commercial paper are obtained by using the OMMT at a concentration of 1 wt%. Water barrier property and thermal stability of paper were also enhanced because of the coating process and the incorporation of OMMT. The results from this study demonstrate that OMMT has a great potential to be incorporated into coating formulations to obtain antibacterial-coated papers with improved properties for various packaging applications. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Italian dialect poet Cesare Pascarella travelled all around the world, noting down in notebooks his keen and caustic observations, and drawing sketches that are a visual reportage of his journeys. The sketches were mounted as a random collage over acidic cardboards that were exposed to direct sunlight in his studio. Their poor state of conservation is related to the use of modern paper: chemical instability of raw materials caused acidification and strong oxidation of the support, with intense yellowing of the surfaces and brittleness of the paper. To ensure future preservation of the drawings, chemical stabilisation with simultaneous alcoholic treatment by deacidification (calcium propionate) and reduction (borane tert-butylamine complex) appeared necessary. To verify its applicability, it was indispensible to characterise the support and identify the nature of all the graphic media. The use of Raman, Infrared, X-ray fluorescence spectroscopies and scanning electron microscopy coupled with X-ray microanalysis allowed us to clear the problems related to the different penetration depth of each analytical technique and the different responses of pigments/dyes to each spectroscopy. The palette, how it varied along the journeys, the different supports used and preparations were completely identified showing a choice of colours compatible with the reduction treatment. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Conductive paper was prepared via in situ chemical oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT) in pulp suspension by using iron(III) p-toluenesulfonate (Fe(OTs)3) as both an oxidant and a dopant source. The deposition of poly(3,4-ethylenedioxythiophene) (PEDOT) on the pulp fiber surface was verified and characterized by ATR-FTIR and SEM analyses. The factors affecting the conductivity of the PEDOT-coated paper were investigated, and the preparation conditions of the conductive paper with a low resistivity and excellent environmental stability was obtained. The optimum reaction temperature and time were 60 °C and 4 h, respectively. The molar ratio of EDOT to Fe(OTs)3 of 1:1 was optimal when considering both cost and performance factors. The conductivity of the PEDOT-coated paper could be controlled by adjusting EDOT concentration. The threshold concentration of EDOT was about 3 g⋅L-1, and a volume resistivity as low as 5.9x10³ Ω⋅cm could be achieved, which reached the conductivity range of an electrical conductor. The environmental stability of the PEDOT-coated conductive paper was very good due to the much higher oxidation potential of PEDOT. [ABSTRACT FROM AUTHOR]

Nanoparticles of partially imidized poly(styrene-maleic anhydride) were applied from an aqueous dispersion as a one- or two-layer coating onto paper substrates, for controlling the paper surface hydrophobicity and improving the water barrier resistance. The effect of deposition conditions and thermal treatments on the topography and properties of the coating was studied by scanning electron microscopy, atomic force microscopy (AFM), contact angle measurements, and friction measurements. The wettability of paper surfaces with adsorbed nanoparticles can be controlled by tuning the chemical and topographical surface parameters: the water contact angles were found to increase at higher imide content as determined by Raman spectroscopy (depending on synthesis and thermal treatment), and higher average surface roughness determined by AFM (depending on the deposition method). The present technique may serve as a unique replacement for chemical treatments hydrophobizing fibrous substrates. [ABSTRACT FROM AUTHOR]

In this work, a study concerning the composition of Italian papers from the seventeenth to the twentieth centuries was carried out using energy dispersive X-ray fluorescence spectrometry (EDXRF), X-ray diffraction (XRD), and scanning electron microscopy coupled to energy dispersive spectrometry (SEM-EDS). The analyzed samples consisted of papers employed for drawing, writing, printing, and absorbance. Observations carried out by SEM magnified the typical paper morphology. EDXRF in combination with XRD and SEM-EDS allowed the determination of calcite, gypsum, kaolin, talc, magnesite, and dolomite, used as fillers in the production of the papers studied herein. The inks present in the handwritten and printed papers, investigated by SEM-EDS and μ-EDXRF, were synthetic, Fe based, and iron gall inks. [ABSTRACT FROM AUTHOR]

Abstract: A sample set of model graded papers containing known organic and inorganic components was used to culture an Aspergillus terreus strain able to produce acidic metabolites and cellulolytic enzymes. This study set out to document the biogenic formation of calcium oxalate crystals, as a consequence of fungal activity and growth, on a range of paper samples. Scanning electron microscopy and FTIR spectroscopy techniques were employed to achieve this end. Bioleaching processes induced by fungi on carbonate used in the manufacture of paper, together with the capacity of fungi to produce – very rapidly – significant biogenesis of monohydrate and dihydrate calcium oxalate crystals on the surface of papers, were investigated. SEM images of calcium containing paper samples disclosed a very clear difference in the pattern of inorganic material distribution when areas spoiled by fungi and those not affected by fungal growth were compared. In addition, the FTIR spectrum of CaCO3 sized paper clearly demonstrated, following fungal growth, the FTIR absorbance of fungus and calcium oxalate, together with the disappearance of carbonate bands. [Copyright &y& Elsevier]

Paper samples were rendered superhydrophobic with Alkyl Ketene Dimer using (1) Airblasting with cryo ground micro particles, (2) crystallizing from organic solvents and (3) spraying with Rapid Expansion of Supercritical Solutions (RESS) technique. The papers were characterized using Scanning Electron Microscopy, contact angle to water measurements and X-ray Photoelectron Spectroscopy (XPS). Advancing contact angles were in the region of 150°–160° and receding contact angles were in the region of 110°–130°. Diagrams showing the drop base diameter vs. the contact angle when water is pumped into, and then withdrawn from, a sessile drop show that a stick slip pattern is present in the advancing phase for a non coated internally sized paper. Papers rendered superhydrophobic with the RESS technique showed a much less pronounced stick slip pattern in the advancing phase but still a stick slip pattern in the receding phase. [ABSTRACT FROM AUTHOR]

Abstract: Lead (Pb) contamination in the black paper that recovers intraoral films (BKP) has been investigated. BKP samples were collected from the Radiology Clinics of the Dental School of Ribeirão Preto, University of São Paulo, Brazil. For sake of comparison, four different methods were used. The results revealed the presence of high lead levels, well above the maximum limit allowed by the legislation. Pb contamination levels achieved after the following treatments: paper digestion in nitric acid, microwave treatment, DIN38414-54 method and TCLP method were 997μgg−1, 189μgg−1, 20.8μgg−1, and 54.0μgg−1, respectively. Flame atomic absorption spectrometry (FAAS) and inductively coupled plasma mass spectrometry (ICP-MS) were employed for lead determination according to the protocols of the applied methods. Lead contamination in used BKP was confirmed by scanning electron microscopy coupled with energy dispersive X-ray microanalysis (SEM-EDS). All the SEM imaging was carried out in the secondary electron mode (SE) and backscattered-electron mode (QBSD) following punctual X-ray fluorescence spectra. Soil contamination derived from this product revealed the urgent need of addressing this problem. These elevated Pb levels, show that a preliminary treatment of BKP is mandatory before it is disposed into the common trash. The high lead content of this material makes its direct dumping into the environment unwise. [Copyright &y& Elsevier]

A new approach to the measurement of x−yuniformity of the surface of a paper sheet is described. Scanning electron micrographs are taken of both the top and bottom surfaces of a paper sheet and image-analyzed. The images were converted to grayscale, and the standard deviation of the pixel brightness was called the “SEM roughness index” and calculated for each surface. Both commercial newsprint sheets and handsheets made with kraft, TMP, and recycled fibers were examined. Debonders and cationic polymers were added to some sheets. The addition of debonders increases the index on the top side of the sheet but decreases it on the bottom. This is caused by the movement of fines from the top to the bottom side. The addition of cationic polymers increases the SEM roughness index by increasing the degree of microfloc formation. Samples taken across a reel from a commercial paper machine tend to show a mirror image relationship between the top and bottom surfaces. The SEM roughness index is able to detect subtle changes in sheet structure caused by differences in the mode of addition of polymers used for retaining fines in the sheet. [ABSTRACT FROM AUTHOR]

Abstract: The paper manufacturing process remained unchanged for many centuries, until, in the nineteenth century, the crisis of rags led industrialized countries to patent new production processes with different raw materials. This study deals with this period of transition by analyzing four samples stored at the archives of Superintendency Beni Architettonici per il Paesaggio e per il Patrimonio Storico Artistico ed Etnoantropologico (BAPPDAD) of Venice Lagoon, based in the Palazzo Ducale. The samples were analyzed by FT-IR (ATR), SEM-EDS, HPLC-MS/MS and Py-GC/MS. These techniques allow the characterization of various raw materials and adhesives used in various stages of paper production. These analyses have found a gradual introduction of ground wood in the composition of papers from the mid-nineteenth century, and the use of rosin as glue only in more recent documents. [Copyright &y& Elsevier]

The article presents a study which investigated the mechanism of foaming with a combination of high-speed photography, scanning electron microscopy, and infrared thermography using foamed paperboard of different compositions prepared both in the laboratory and on a commercial machine. The study addresses the fundamental mechanism of foaming and identify the characteristics of the board that lead to a product with evenly distributed bubbles of a uniform size. The study attempts to understand the fundamental mechanism of foaming on paper-polymer composites.

Paper, mainly constituted of cellulose fibres, often contains mineral fillers. These fillers increase some of the properties of the paper (whiteness, printability, etc.) and are cheaper than the cellulose fibres. Nevertheless, the fillers reduce the mechanical properties of the sheet. Paper presents an anisotropy corresponding to three main directions. This anisotropy characterises the sheet mechanical properties, structure and filler distribution. Analyses of the cross section of the paper sheet with a low-vacuum scanning electron microscope with an energy dispersive spectrometer analysis module can show this distribution. The procedure developed consists in analysing discrete profiles to build the mean profile known as filler Z-distribution for each of the fillers. To develop this method, problems such as determination of the surface points, the number of points to analyse to define a cross section profile and the time required for the test, have been solved. Paper is sensitive to electron irradiation. In order to avoid deterioration of the material and to obtain satisfactory results, the time span for analyses is restricted to 40 s with a 12 kV electron beam accelerating voltage. Monte Carlo simulations are used to determine the diffusion cloud size and thus to determine the number of points that constitute a profile. The samples are gold sputtered and, with the aid of backscattered imaging, the coated surface allows determination of the sample surface points. [ABSTRACT FROM AUTHOR]

The article discusses the morphological analysis of paper images through scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The materials are segmented into individual fibers to determine their digital measurements using secondary electron detector. Calcium carbonate particles resulted to the formation of fillers characterized by large amounts of coarse edge fibers and irregular granules. Furthermore, fiber borders with small size width are accidentally identified, however, they represent flat and peak directions.

We present a novel method to get information on the difference in gloss before and after surface processing (delta gloss) by scanning a sample with a diffractive glossmeter. In addition, we utilize scanning electron microscopy (SEM) to inspect the surface. We introduce novel statistical parameters for the quantification of the delta gloss of prints before and after printing on paper samples. [ABSTRACT FROM AUTHOR]

TiO2 powder-containing paper composites, called TiO2 paper, were prepared by a papermaking technique, and their photocatalytic efficiency was investigated. The TiO2 paper has a porous structure originating from the layered pulp fiber network, with TiO2 powders scattered on the fiber matrix. Under UV irradiation, the TiO2 paper decomposed gaseous acetaldehyde more effectively than powdery TiO2 and a pulp/TiO2 mixture not in paper form. Scanning electron microscopy and mercury intrusion analysis revealed that the TiO2 paper had characteristic unique voids ca. 10μm in diameter, which might have contributed to the improved photocatalytic performance. TiO2 paper composites having different void structures were prepared by using beaten pulp fibers with different degrees of freeness and/or ceramic fibers. The photodecomposition efficiency was affected by the void structure of the photocatalyst paper, and the initial degradation rate of acetaldehyde increased with an increase in the total pore volume of TiO2 paper. The paper voids presumably provided suitable conditions for TiO2 catalysis, resulting in higher photocatalytic performance by TiO2 paper than by TiO2 powder and a pulp/TiO2 mixture not in paper form. [Copyright &y& Elsevier]