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[Display omitted] • An amphiphobic paper was fabricated via internal sizing technology. • The modified paper exhibited high resistance to moisture and water vapor. • The modified paper maintained high fracture stress in high humidity environment. • The modified paper exhibited notable self-cleaning and antibacterial activity. Paper-based materials have been used in every aspect of social life. However, the current paper-based materials face unprecedented challenges, such as limited lifespan and poor mechanical strength, owing to the deformation after absorbing a large amount of water and bacterial erosion. Herein, superhydrophobic and lyophobic paper was fabricated using internal sizing technology. Hydrophobically modified starch and Ag@SiO 2 particles were added as two functional additives to paper pulp to promote a hierarchical structure formation with low surface energy. Consequently, the water and linseed oil contact angles of the obtained paper reached 154.8° and 138.4°, respectively. The resistance to moisture and water vapor also improved under high-humidity condition, the relative moisture content decreased from 511% to 278% and water vapor transmission rate also decreased from 97.44 to 21.23 g/m2·h. Furthermore, its mechanical properties could also be well maintained with a high fracture stress of 4.91 MPa. Besides, some liquid food, such as honey, easily rolled off the surface without leaving behind any residue, which demonstrated its self-cleaning ability. Furthermore, the modified paper exhibited notable bacterial repellency and antibacterial activity. This study provides an innovative method for endowing conventional paper with superhydrophobic and antibacterial properties, which can effectively expand their application scope. [ABSTRACT FROM AUTHOR]

In this work, we use paramagnetic defects induced by gamma radiation in some modern paper samples to determine their main dosimetric properties in the decontamination dose range (0.5–10 kGy) of ancient papers. Electron spin resonance (ESR) spectra of photo paper, cigarette paper, white paper napkin (napkin), cash register receipt, straw paper and white photocopy paper recorded before and after irradiation with gamma rays were reported. Photo paper, cigarette paper and napkin samples displayed the radiation-induced cellulose-like ESR signals well known from the literature on cellulose-containing foods. Cash register receipt, straw paper, and white photocopy paper are another set of samples where different ESR spectra were recorded. The ESR signals of these three paper samples were shown to originate from carbonate mineral filler grains. Inorganic mineral fillers are commonly used in paper manufacturing. The dose-response curves associated with the radiation-induced sharp ESR signals originating from the CaCO 3 filler of the cash register receipt (g = 2.0027), the straw paper (g = 1.9995), and the white photocopy paper (g = 1.9996) were found to follow a single exponential saturation function. Despite the observed decreases with time in the signal intensities of cash register receipt and white photocopy paper, detectable ESR signals were obtained even 100 days after irradiation for them and straw paper. The radiation-induced free radicals responsible for the ESR spectrum of straw paper were more stable than those of cash register receipt and white photocopy paper. The results indicate that free radicals induced in mineral CaCO 3 filler grains incorporated within papers have the potential to be used for application to retrospective ESR dosimetry in the range of 0.5–10 kGy. • Radiation-induced ESR signals were examined in six types of modern papers. • Cellulose-like and calcite filler origin signals were observed in the papers. • ESR signals originating from calcite filler increased exponentially in the range 0.5–10 kGy. • The fading behaviors of the signals were investigated depending on the dose. • Common modern papers were tested as potential retrospective ESR dosimeters. [ABSTRACT FROM AUTHOR]

Ex-situ mineral carbonation, a CCU process, is one possible approach for the decarbonisation of emission-intensive industry with hard-to-abate process emissions like the cement industry. The chemical reaction ensures long-term binding of carbon dioxide in minerals with the effect of storing otherwise emitted CO 2 long term. As a major hurdle for CCU processes is often their economic viability, to create incentives for the usage of this process, these carbonated mineral products must become marketable. A separation approach for the reaction products of this process and possible utilization paths are presented. The separation results in three different fractions, each enriched in either the reaction products amorphous silica or magnesium/calcium silicate or unreacted peridotite. The fractions enriched with reaction products are tested as supplementary cementitious material in cement or as a filler in rubber and paper. The application tests show promising results, comparable or even better than the conventional product. Additionally, based on the laboratory explorations, we present initial economic and environmental investigations showing potential carbon footprint reductions of up to 27% for blended cement with a total global reduction potential of 681 Mt CO2e /a. Also, potential carbon footprint reductions of 52% can be achieved by using carbonation products as fillers in rubber and 197% in paper, respectively. While the costs for the utilization of carbonated minerals have been calculated to be higher than for the conventional products, CO 2 emission certificates could ensure the same price for cement and even lower costs for the substitution of fillers in paper and rubber. [Display omitted] • The technical feasibility of the separation of the carbonation products by centrifugal classification has been proven. • Yield of the separation process can be optimized by better liberation of the particles. • Application tests for cement, paper or rubber show the potential of the carbonated and separated products as a (partial) substitute. • The modeled industrial process – in this case a cement plant with carbonation products as clinker substitute – is ecological and economical feasible. [ABSTRACT FROM AUTHOR]

Historic works on paper, illuminated (painted) or unpainted manuscripts, and textiles are fragile and nearly impossible to sample. Non-invasive techniques such as visible microscopy, X-ray fluorescence, Raman, and reflectance spectroscopy are commonly used to determine the artist material present. Recently, nonlinear optical ultrafast pump-probe microscopy was shown to provide non-invasive, high-resolution mapping of pigments in historic paintings to investigate paint stratigraphy. In this paper, we combine our pump-probe contrast with nonlinear fluorescence and second-harmonic generation contrasts exhibited by fibrous supports composed of natural bio-materials (cellulose, collagen, or lignin). Hence, our multi-modal nonlinear microscope is able to simultaneously investigate pigments in conjunction with their support in three dimensions with micrometer-scale spatial resolution. Here we examine the utility of nonlinear pump-probe microscopy by studying a series of mock-up samples, including indigo-dyed cotton cloth, ultramarine blue painted on various types of paper, and papers painted with mixtures and layers of the two pigments. In each case we find that we can combine pump-probe pigment contrast with nonlinear optical fiber contrast to obtain spatial information that is otherwise unavailable to the conservator. [ABSTRACT FROM AUTHOR]

Cellulose oxidative and hydrolytical degradation is one of the greatest problems for the conservation of paper supports. To contrast these degradation processes, both deacidification and reduction of the oxidized functions are needed. Dealing with original documents, it is often impossible to perform the two mentioned treatments in aqueous solutions and in a distinct subsequent way, because of the fragility of the artifacts. After studying, in a separate way, an effective deacidifier (calcium propionate) soluble in ethyl alcohol and many reducers (boron complexes), able to act in different non-aqueous solvents, it was decided to test a simultaneous method of deacidification and reduction in ethanol. This paper presents the chemical-physical results obtained by applying simple deacidification and simultaneous deacidification-reduction on laboratory paper samples that were artificially aged and then re-measured after 10 and 15 years of natural aging. Results show that all alcoholic treatments are very effective: papers are stable also after a long period of both artificial and natural aging. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO)/cellulose paper was prepared by adding aqueous dispersion of GO into cellulose fiber pulp in a traditional papermaking procedure. Cationic polyacrylamide (CPAM) was added as a mordant to induce the self-assembly of GO layers on the fiber surfaces. The surface morphology, mechanical properties and gas permeability of GO/cellulose paper with varying GO contents were investigated by scanning electron microscopy (SEM), tensile test, burst test, tear test and densometer. It was found that CPAM could prevent the self-aggregation of GO in fiber matrix and increase the loading efficiency of GO to up to 16 wt% without sacrificing the mechanical performances of the paper. This finding permitted the large scale preparation of GO/cellulose paper with high doping amount of GO, which exhibited dense and compact geometry and low gas permeability ideal for potential packaging applications. [ABSTRACT FROM AUTHOR]

Paper microfluidics is used to produce single layer galvanic and hybrid cells to produce energy that could power paper-based analytical sensors. When two aqueous streams are absorbed onto paper to establish co-laminar flow, the streams stay in contact with each other with limited mixing. The interface at which mixing occurs acts as a charge-transfer region, eliminating the need for a salt bridge. We designed a Cu Zn galvanic cell that powers an LED when two are placed in series. We also used more powerful redox couples (formate and silver, formate and permanganate) to produce higher power density (18 and 3.1 mW mg −1 Pd). These power densities are greater than previously reported paper microfluidic fuel cells using formate or methanol. The single layer design is much more simplified than previous reports of multi-layer galvanic cells on paper. [ABSTRACT FROM AUTHOR]

A multi-amplified paper-based electrochemical strategy using Pb 2+ dependent DNAzyme as the recognition unit for Pb 2+ detection was developed. In this work, flower-like reduced graphene (FrGO) was prepared utilizing flower-like ZnO as template, which was first one step grown on the gold nanoparticles modified paper working electrode (Au-PWE). After being treated with acid and then modified with Au, a novel sensor platform named Au/FrGO/Au-PWE with large specific surface area and good electrical conductivity was fabricated. The Mn 2 O 3 nanoparticle-assembled hierarchical hollow spheres (H-Mn 2 O 3 ) was served as nanocarrier to immobilize GOx, HRP and signal strand (S3), resulting to the formation of S3/H-Mn 2 O 3 /HRP/GOx bioconjugations. In the presence of Pb 2+ , the DNAzyme (S1) was activated and the substrate strand (S2) was cleaved. After the incubation with S3/H-Mn 2 O 3 /HRP/GOx in 0.1 M HAc–NaAc solution (pH 4.3) containing 30 mM aniline and 15 mM glucose, a readily measurable “turn-on” electrochemical signal could be measured. On the basis of the signal amplification strategy of Au/FrGO/Au-PWE sensing platform and S3/H-Mn 2 O 3 /HRP/GOx bioconjugations, the developed biosensor exhibited a good linear response toward over a wide range of concentration from 0.005 to 2000 nM. [ABSTRACT FROM AUTHOR]

We report a novel biodegradable piezoelectric composite fabricated from paper and the piezoelectric salt, sodium potassium tartrate tetrahydrate (Rochelle salt, which we term PiezoSalt). The piezoelectric composite is non-toxic and is fabricated free of environmentally harmful solvents by impregnating PiezoSalt into a paper matrix through the crystallization of a concentrated PiezoSalt brine solution. The composite exhibits an effective piezoelectric constant between 3 and 25 pC N −1 , dielectric constant of 7, mass density of 625 kg m −3 , and a Young’s modulus between 7 and 8 GPa. When directly actuated, cm-scale cantilevers consisting of PiezoSalt paper produced clearly audible sound waves, illustrating one potential application. PiezoSalt paper composite provides a scalable, high throughput approach for biodegradable sensors and transducers with unsurpassed environmentally friendly processing. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the feasibility of using highly filled powders as electrostatically applied paper coatings. Powders prepared by two different methods were suitable for electrostatic deposition and they attached to the paper surface with a grounded backing. Pressing at elevated temperatures turned out to be a crucial process step for improving the adhesive and cohesive strengths of the powder coating layer on paper. Limited mechanical interlocking with the base paper and an uneven pressure profile were factors impairing the surface strength of the coated paper. On the other hand, factors such as higher polymer content, higher pressing temperature, pre-heating the paper prior to coating, and increasing the number of hot roll nips increased adhesion between the coating and the base paper. Powder coatings as such had uneven thickness, and they displayed a relatively broad pore size distribution. [ABSTRACT FROM AUTHOR]

Laccases are enzymes belonging to the group of oxidases. Laccases catalyze the oxidation of a variety of phenolic compounds, diamines and aromatic amines. Twenty-four fungal isolates were isolated from biodeteriorated ancient paper and parchment. These isolates were identified and found to belong to six genera: Alternaria , Aspergillus , Cladosporium , Penicillium , Rhizopus and Trichoderma , and were tested for producing laccase enzyme. Trichoderma harzianum have the ability of secreted laccase enzyme. The maximum production of laccase enzyme by T. harzianum was observed at 35 ○ C and pH 5 after 6 days. The highest activity of laccase achieved at 35 ○ C and pH 5 during the reaction. FTIR analysis revealed that the structure of extracted fungal pigments has aromatic ring and phenols group. Crude laccase was capable to decolorize different pigment structures. The enzyme showed great decolorization efficiency toward the extracted yellow pigment produced from Asp. terrus and Asp. ochareceous treated by 200 μl of partially purified enzyme. Laccase enzyme was used to decolorization pigment secreted from deteriorated pigmented fungi on paper and parchment during 30 days by using a pieces of paper and parchment inoculated by spore suspension. The results indicated that a high removal effect of fungal pigment on paper (71.21%) was recorded comparing to parchment samples (32.39%). [ABSTRACT FROM AUTHOR]

This article presents a novel method for integrating native corn starch and calcium carbonate (CaCO 3 ) into a hybrid pigment, which can be applied in papermaking to increase the amount of starch in paper and improve sheet bonding without impairing dewatering. Starch was first thermally treated to partially gelatinize and swell the granules. The aim of the treatment was to change the surface properties of starch and thus to improve the interaction with CaCO 3 particles. CaCO 3 shell was precipitated around the swollen granules and the encapsulated starch was then cooked to achieve complete gelatinization. When the granules were cooked, the starch became active for bonding, but its solubility was very limited due to the encapsulation. Particle size measurement and scanning electron microscopy were used to analyze the sample properties during the preparation. The hybrid pigment was added to paper sheets and its effect on the paper properties was examined. Starch was shown to be effectively bound to the pigment structure. The hybrid pigment allowed a large amount of native corn starch to be added to paper without interfering with the papermaking process. Furthermore, it gave excellent mechanical paper properties. [ABSTRACT FROM AUTHOR]

We report the fabrication of a paper-sensor for quantitative detection of α -amylase activity in human blood serum. Pieces of filter papers were coated with starch–iodine solution leading to an intense blue coloration on the surface. Dispensing α- amylase solution on the starch–iodine coated paper reduced the intensity of the color because of starch-hydrolysis catalyzed by amylase. The variation in the intensity of the color with the concentration of amylase was estimated in three stages: (i) initially, the paper-surface was illuminated with a light emitting diode, (ii) then, the transmitted (reflected) rays emitted through (from) the paper were collected on a photoresistor, and (iii) the variations in the electrical resistance of the photoresistor were correlated with the amylase concentration in analyte. The resistance of photoresistor decreased monotonically with an increase in amylase concentration because the intensity of the reflected (transmitted) rays collected from (through) the paper increased with reduction in the color intensity on the paper surface. Since a specific bio-reaction was employed to detect the activity of amylase, the sensor was found to be equally efficient in detecting unknown quantities of amylase in human blood serum. The reported sensor has shown the potential to graduate into a point-of-care detection tool for α- amylase. [ABSTRACT FROM AUTHOR]

This report describes for the first time the development of paper-based enzymatic reactors (PERs) for the detection of glucose (Glu) in artificial serum sample using a 3D printed batch injection analysis (BIA) cell coupled with electrochemical detection. The fabrication of the PERs involved firstly the oxidation of the paper surface with a sodium periodate solution. The oxidized paper was then perforated with a paper punch to create microdisks and activated with a solution containing N -hydroxysuccinimide (NHS) and N -(3-dimethylaminopropyl)- N ′-ethylcarbodiimide hydrochloride (EDC). Glucose oxidase (GOx) enzyme was then covalently immobilized on paper surface to promote the enzymatic assay for the detection of Glu in serum sample. After the addition of Glu on the PER surface placed inside a plastic syringe, the analyte penetrated through the paper surface under vertical flow promoting the enzymatic assay. The reaction product (H 2 O 2 ) was collected with an electronic micropipette in a microtube and analyzed in the 3D BIA cell coupled with screen-printed electrodes (SPEs). The overall preparation time and the cost estimated per PER were 2.5 h and $0.02, respectively. Likewise the PERs, the use of a 3D printer allowed the fabrication of a BIA cell within 4 h at cost of $5. The coupling of SPE with the 3D printed cell exhibited great analytical performance including repeatability and reproducibility lower than 2% as well as high sampling rate (30 injections h −1 ) under low injection volume (10 μL). The limit of detection (LD) and linear range achieved with the proposed approach was 0.11 mmol L −1 and 1–10 mmol L −1 , respectively. Lastly, the glucose concentration level was successfully determined using the proposed method and the values found were not statistically different from the data achieved by a reference method at confidence level of 95%. [ABSTRACT FROM AUTHOR]

In the past, the animal glues were used in paper manufacturing and in restoration of artworks preserved in museums, libraries and archives. By ageing they went through deterioration creating distortions, tensions, cockling and discolouration in paper materials. Consequently, the removal of glue residues becomes an essential step in the restoration of ancient and artwork paper material. Current mechanical and chemical methods display serious drawbacks mainly related to aggressiveness towards material or toxicity for restorers. Bio-based methods for paper cleaning rely on the use of enzymes that require skilled operators, optimal application conditions and high costs, creating difficulties in mastering enzyme use so far. This paper describes a first attempt of biocleaning ancient paper from organic deposits using living bacteria. The non-pathogenic, non-spore-forming and non-cellulolytic original strain Ochrobactrum sp. TNS15 E was successfully applied -immobilised in an agar gel-on original paper specimens dating back to the 17th. After 4 h of contact with the bacterial pack, the cellulose fibres underlying glue were disclosed, highlighting the bacterial capacity of removing the glue layer without damaging the paper or leaving undesirable residues. Both colorimetry and SEM analyses proved the results. The procedure is simple, low-cost and safe for the artefact, the restorers and the environment. [ABSTRACT FROM AUTHOR]

Paper is increasingly recognized as a user-friendly and ubiquitous substrate for construction of microfluidic devices. Microfluidic paper-based analytical devices (μPADs) provide an alternative technology for development of affordable, portable, disposable and low-cost diagnostic tools for improving point of care testing (POCT) and disease screening in the developing world, especially in those countries with no- or low-infrastructure and limited trained medical and health professionals. We in this review present fabrication techniques for microfluidic devices and their respective applications for biological detection as reported to date. These include: (i) fabrication techniques: examples of devices fabricated by using two-dimensional (2D) and three-dimensional (3D) methods; (ii) detection application: biochemical, immunological and molecular detection by incorporating efficient detection methods such as, colorimetric detection, electrochemical detection, fluorescence detection, chemiluminescence (CL) detection, electrochemiluninescence (ECL) detection, photoelectrochemi (PEC) detection and so on. In addition, main advantages, disadvantages and future trends for the devices are also discussed in this review. [ABSTRACT FROM AUTHOR]

In parallel with the development of nanoparticle coatings for protection of paper substrates, detailed descriptions of the surface topography with micro- to nanoscale roughness features are needed. In this work, papers have been coated with poly(styrene-co-maleic anhydride) nanoparticles including different types of vegetable oils and the surface roughness was evaluated at 2000 × 2000 μm 2 to 0.2 × 0.2 μm 2 length scales by combining non-contact optical profilometry (NCP) and atomic force microscopy (AFM). The relationships between roughness data were studied for statistical roughness parameters, spatial roughness parameters and in the frequency domain. In order to compare AFM roughness more accurately, the original images were flattened to remove effects of the underlaying fibrous substrate and highlight features of the nanoparticle coating. More detailed information on the coating topography could be obtained by considering bearing ratio curves and histograms, where it was concluded that the oil-filled coatings form a rather thin and continuous coating that closely follows the shape of the cellulose fibers. The relation between statistical roughness parameters from NCP and AFM follows an exponential trend with relatively low coefficient of determination. The increase in surface roughness with length scale showed a transition point attributed to short- and long-range surface features. Therefore, the correlation length was used as a spatial roughness parameter that provides a successful extrapolation of the average roughness over different length scales in a double logarithmic diagram with very high coefficient of determination. Based on the power spectral density, it was difficult to exactly distinguish between the different types of SMI/oil coatings, as they include similar nanoscale features. The frequency roughness parameters were better suited for extrapolation than statistical roughness parameters but little less efficient than the spatial roughness parameters. [ABSTRACT FROM AUTHOR]

This article details the study of electrochemical behavior of new carbon electrodes based on pyrolysis of different paper sources to be used in biosensor applications. The resistivity of the pyrolyzed papers was initially used as screening parameters to select the best three paper samples (imaging card paper, multipurpose printing paper, and 3MM chromatography paper) and assemble working electrodes that were further characterized by a combination of microscopy, electrochemistry, and spectroscopy. Although slight differences in performance were observed, all carbon substrates fabricated from pyrolysis of paper allowed the development of competitive biosensors for uric acid. The presented results demonstrate the potential of these electrodes for sensing applications and highlight the potential advantages of 3MM chromatography paper as a substrate to fabricate electrodes by pyrolysis. [ABSTRACT FROM AUTHOR]

A severe decay process, catalyzed by acidity and metal ions, affects cellulose in historical manuscripts and books that contain iron gall inks. The inhibition of this process can be achieved by alkaline-earth nanoparticles dispersions in alcohols, which create a neutral environment in which both oxidation and depolymerization of cellulose are hindered. As a result of the degradation process, paper in historical manuscripts and books is fragile and very difficult to handle. A reinforcement intervention with gelatin and Japanese tissue could be used for the strengthening of historical manuscripts, even if this method could not prevent paper degradation due to iron gall inks. Therefore, a new method, combining a deacidification treatment based on calcium hydroxide nanoparticles and a reinforcement process using Japanese tissue has been developed and tested on mockups containing iron gall inks. The protective action arising from the combined treatment was evaluated by performing cellulose viscosimetric degree of polymerization (DPv) and pH measurements on artificially aged systems. Scanning electron microscopy equipped with energy dispersive X-ray spectroscopy (SEM-EDX) was used for the evaluation of calcium distribution from the deacidification agent within samples cross section. Determinations of DPv clearly showed that the degradation of untreated inked paper was significantly slowed down by the combined treatment. The method was also tested on original manuscripts from 16th and 18th century. SEM-EDX maps showed that the applied treatment, which raised the pH to an appropriate value, is homogenously distributed over the treated surfaces. [ABSTRACT FROM AUTHOR]

Food contact materials (FCMs) have been reported as a source of various xenobiotics. This study investigates the possibility of simultaneous analysis of 68 potential contaminants in paper FCMs, specifically phthalates, polycyclic aromatic hydrocarbons, photoinitiators, bisphenols, and polyfluorinated compounds. Target compounds were co-isolated using a technique based on ultrasonic extraction by mixture of acetonitrile and water followed by QuEChERS-like liquid–liquid partition in the presence of inorganic salts. Resulting extracts were analyzed using gas and high performance liquid chromatography coupled with tandem mass spectrometry (GC–MS/MS, HPLC–MS/MS). Acceptable recoveries (70–120%) and RSDs (<20%) were achieved for most of the analytes at spiking levels of 0.05, 0.2 and 1 mg/kg. LOQs ranged from 0.0013 to 0.22 mg/kg. The proposed method was successfully applied to analysis of 15 real samples. Complex mixtures of contaminants reaching levels up to 48 mg/kg were identified in the samples. [ABSTRACT FROM AUTHOR]

Paper, a readily available renewable resource, comprises of interwoven cellulosic fibers, which can be functionalized to develop interesting low-cost adsorbent material for water purification. In this study, polyethyleneimine (PEI)-functionalized paper was used for the removal of hazardous pollutants such as Au and Ag nanoparticles, Cr(VI) anions, Ni 2+ , Cd 2+ , and Cu 2+ cations from spiked water samples. Compared to untreated paper, the PEI-coated paper showed significant improvement in adsorption capacities toward the pollutants investigated in this study. Kinetics, isotherm models, pH, and desorption studies were carried out to study the adsorption mechanism of pollutants on the adsorbent surface. Adsorption of pollutants was better described by pseudo-second order kinetics and Langmuir isotherm model. Maximum adsorption of anionic pollutants was achieved at pH 5 while that of cations was at pH > 6. Overall, the PEI-functionalized paper showed interesting Langmuir adsorption capacities for heavy metal ions such as Cr(VI) (68 mg/g), Ni 2+ (208 mg/g), Cd 2+ (370 mg/g), and Cu 2+ (435 mg/g) ions at neutral pH. In addition, the modified paper was also used to remove Ag-citrate (79 mg/g), Ag-PVP (46 mg/g), Au-citrate (30 mg/g), Au-PVP (17 mg/g) nanoparticles from water. Desorption of NPs from the adsorbent was done by washing with 2 M HCl or thiourea solution, while heavy metal ions were desorbed using 1 M NaOH or HNO 3 solution. The modified paper retained its extraction efficiencies upon desorption of pollutants. [ABSTRACT FROM AUTHOR]

We compared the effects of two media (paper vs. computer) on reading comprehension and memorization among students in their third or fourth year of secondary school. To assess comprehension, we constructed and validated a text with a carefully controlled hierarchical structure, accompanied by a questionnaire containing three types of questions (surface, semantic, inference). Memory of the text was assessed with a test based on the Remember-Know (R/K) paradigm. The results of the comprehension and R/K tests indicated that there was no difference between the two media. Regardless of medium, surface comprehension was better than either semantic or inference comprehension. The R/K test indicated that memorization was better for the surface elements of the text (more R than K responses). In conclusion, overall results show that if we fulfil all the conditions of paper-based versus computerized presentation (text structure, presentation on a single page, screen size, several types of questions measuring comprehension and memory performances), reading performances are not significantly different. [ABSTRACT FROM AUTHOR]

In this paper, members of three research teams, namely the Turfan Project of the Berlin Brandenburg Academy of Sciences and Humanities, the Berlin-based research project on pigments in Central Asian paper manuscripts, and the Hamburg-based project on the history and typology of Central Asian paper manuscripts, present some of the results of their cooperation. The investigated manuscripts belong to the Berlin Turfan Collection. On the basis of different examples the contribution of scientific methods to philological scholarship within a multidisciplinary approach is demonstrated. [ABSTRACT FROM AUTHOR]

In this work, the fabrication of Rochelle salt based piezoelectric structures is illustrated. Structures composed of paper and Rochelle salt are easily manufactured using simple processes. Both manufacturing and the material itself are environmental friendly. Additionally Rochelle salt is biocompatible. In the paradigm of a cleaner piezoelectric technology, the fabrication of active sensing or actuating devices is developed. Thus processing method, material and piezoelectric properties have been studied: (1) pure crystals are used as acoustic actuator, (2) properties of paper impregnated with Rochelle salt are detailed, (3) charge generation is demonstrated on the impregnated material. Actuating and sensing devices are reported in order to highlight the potential of this green piezoelectric material. [ABSTRACT FROM AUTHOR]

The tensile response of dense fiber-based materials like paper or paperboard is mainly dependent of the properties of the fibers, which store most of the elastic energy. In this paper, we investigate the influence of geometrical and material parameters on the mechanical response of the pulp fibers used in paper manufacturing. We developed a three-dimensional finite element model of the fiber, which accounts for microfibril orientation of cellulose fibril, and the presence of lignin in the secondary cell wall. The results showed that the change in the microfibril orientation upon axial straining is mainly a geometrical effect, and is independent of the material properties of the fiber, as long as the deformations are elastic. Plastic strain accelerates the change in microfibril orientation and thus makes it material-dependent. The results also showed that the elastic modulus of the fiber has a non-linear dependency on microfibril angle, with elastic modulus being more sensitive to the change of microfibril angle around small initial values of microfibril angles. Based on numerical results acquired from a 3D fiber model supported by available experimental evidence, we propose an anisotropic-kinematic hardening plasticity model for a fiber within a beam framework. The proposed fiber model is capable of reproducing the main features of the cyclic tensile response of a pulp fiber, such as stiffening due to changing microfibril angle. The constitutive model of the fiber was implemented in a finite-element model of the fiber network. By using the fiber network model, we estimated the level of strain that fiber segments accumulate before the typical failure strain of the entire network is reached. [ABSTRACT FROM AUTHOR]

Materials sliding on a larger substrate age faster than the substrate itself, but no available model of friction takes into account this aspect. We developed a model based on the memory effect of both the mobile and the plane samples, separately, and characterized by macroscopic geometric measurements (e.g., sliding distances and samples sizes). We studied the contact between fresh paper samples and samples that have already underwent several slidings. Experimental and theoretical results are in good agreement. Finally, we used our model to demonstrate how the existing test methods can lead to differences in the measured forces of friction. The results allow both a better understanding and quantitative characterization of the dependence of friction with the history of the contact. [ABSTRACT FROM AUTHOR]

Different methods for measuring the friction forces are investigated in this paper. We consider the paper-on-paper contact as an example of application. We first underline several drawbacks for the two main standard methods, namely the inclined and horizontal plane methods. In particular, the horizontal plane test method often involves stick-slip oscillations that make the measurement of the friction force impossible. We then propose a method for characterizing these oscillations and removing their influence on the friction force measurement. The comparison of the proposed method to standards suggests that our proposed method delivers measurements that are much more accurate and repeatable. We finally discuss the validity of averaging the friction force measured during the sliding movement. [ABSTRACT FROM AUTHOR]

Considerable advances in point-of-care testing (POCT) devices stem from innovations in cellphone (CP)-based technologies, paper-based assays (PBAs), lab-on-a-chip (LOC) platforms, novel assay formats, and strategies for long-term reagent storage. Various commercial CP platforms have emerged to provide cost-effective mobile health care and personalized medicine. Such assay formats, as well as low-cost PBAs and LOC-based assays, are paving the way to robust, automated, simplified, and cost-effective POCT. Strategies have also been devised to stabilize reagent storage and usage at ambient temperature. Nevertheless, successful commercialization and widespread implementation of such clinically viable technologies remain subject to several challenges and pending issues. [ABSTRACT FROM AUTHOR]

This manuscript describes the development and clinical testing of a paper-based, metabolic assay designed for rapid, semi-quantitative measurement of organophosphate poisoning. Paper-based platforms, including point-of-care devices and 96-well plates, provided semi-quantitative information regarding the concentration of AchE (a biomarker for organophosphate poisoning). The paper-based 96-well-plate developed and implemented in this study was used to measure the level of organophosphate poisoning in three different clinical patients. Results were comparable to those obtained using conventional hospital methods currently considered the “gold standard”. This diagnostic device offers several advantages over conventional methods, including short operating time (twice as fast as conventional methods), procedure simplicity, and reduced fabrication cost. With further commercialization efforts, the methods described in this manuscript could be applied to a wide range of potential diagnostic applications in the field. [ABSTRACT FROM AUTHOR]

Paper product manufacturing involves a variety of chemicals used either directly in paper and pulp production or in the conversion processes (i.e. printing, gluing) that follow. Due to economic and environmental initiatives, paper recycling rates continue to rise. In Europe, recycling has increased by nearly 20% within the last decade or so, reaching a level of almost 72% in 2012. With increasing recycling rates, lower quality paper fractions may be included. This may potentially lead to accumulation or un-intended spreading of chemical substances contained in paper, e.g. by introducing chemicals contained in waste paper into the recycling loop. This study provides an overview of chemicals potentially present in paper and applies a sequential hazard screening procedure based on the intrinsic hazard, physical–chemical and biodegradability characteristics of the substances. Based on the results, 51 substances were identified as potentially critical (selected mineral oils, phthalates, phenols, parabens, as well as other groups of chemicals) in relation to paper recycling. It is recommended that these substances receive more attention in waste paper. [ABSTRACT FROM AUTHOR]

Water soluble cationic chitosan (C-Ch) and surface-modified microfibrillated cellulose (C-MFC) were prepared and characterized. C-MFC was prepared by reaction of MFC (microfibrillated cellulose) with β-chloroethyldiethylamine followed by quaternization using methyl iodide while C-Ch was prepared by reaction of a commercial chitosan (Ch) with 2,3-epoxypropyltrimethyl ammonium chloride. C-Ch and C-MFC were characterized by elemental analysis (nitrogen content), Fourier transform infrared spectroscopy (FTIR) and surface charge determination. The prepared C-Ch and C-MFC were used with bentonite in order to improve drainage and filler retention in paper handsheets made from softwood and bagasse pulps. Dosage rates were 0.05–0.2% (w/w, weight of additive by weight of fibres) and 0.05–1% (w/w) for C-Ch and C-MFC, respectively. When used alone, these polymers did not induce any noticeable effect on drainage but they improved the retention of ground calcium carbonate (GCC). The effect of C-MFC/bentonite and C-Ch/bentonite systems on filler retention was more pronounced in case of bagasse pulp than for softwood pulp. The use of C-Ch improved filler retention more than C-MFC did. Comparisons with a commercially available cationic polyacrylamide (CPAM) showed that CPAM was the most efficient additive regarding both drainage and GCC retention, followed by Ch, C-Ch, and finally C-MFC. [ABSTRACT FROM AUTHOR]

Conductivity of the poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) strongly depends on the film morphology, which can be altered by the presence of polyelectrolytes. Aqueous dispersion of PEDOT:PSS was studied with anionic sodium polyacrylate (PA) and cationic poly(dimethyldiallylammonium chloride) (pDADMAC) polyelectrolytes that are typically used in papermaking as retention aids and dispersing agents in the paper pigment coating formulations. Spin-coated PEDOT:PSS films on a PA coated glass formed non-uniform layers with lowered conductivity compared to the reference PEDOT:PSS films on a clean glass substrate. On contrary, spin-coated PEDOT:PSS on a pDADMAC coated glass formed uniform layers with good conductivity. These results point out the importance of surface chemistry when using renewable and recyclable paper-based substrates with the PEDOT:PSS films. [ABSTRACT FROM AUTHOR]

A novel method has been developed for the determination of the diffusion ( D ) and solid–air partition ( K d ) coefficients of methanol in paper materials. The method used a solvent-assisted vapor absorption based headspace analysis technique to increase the driving force of the mass transfer process in the solid phase. Equations based on the established physical models described the process allowed the calculation of D and K d of methanol in paper materials from the GC signals and experimental settings. The results showed that the amount of methanol transferred from the paper sheet can be significantly increased by the presence of the assisting triacetin. The solvent-assisted vapor absorption equilibrium can be obtained in 20 min. The method also generated equations allowing for the calculation of D and K d of methanol in paper materials at any temperature. The present method is simpler and quicker than the chamber methods that are in widespread use today and should be of special interest to those concerned about the impact of food and beverage packaging on human health. [ABSTRACT FROM AUTHOR]

Well-dispersed Fe 3 O 4 nanoparticles (NPs) were synthesized by a co-precipitation method in the presence of cellulose nano-crystals (CNC) as the template. The thus prepared Fe 3 O 4 NPs were then used as a coating agent for the preparation of conductive paper. Fourier transform infrared spectroscopy (FTIR) results revealed that the Fe 3 O 4 NPs were immobilized on the CNC through interactions between the hydroxyl groups of CNC and Fe 3 O 4 . Scanning transmission electron microscopy (STEM) images showed that the Fe 3 O 4 NPs prepared in the presence of CNC can be dispersed in the CNC network, while the Fe 3 O 4 NPs prepared in the absence of CNC tended to aggregate in aqueous solutions. The conductivity of the Fe 3 O 4 NPs coated paper can reach to 0.0269 S/m at the coating amount of 14.75 g/m 2 Fe 3 O 4 /CNC nanocomposites. Therefore, the thus obtained coated paper can be potentially used as anti-static packaging material in the packaging field. [ABSTRACT FROM AUTHOR]

Natural self-assembled microstructured particles (diatomaceous earth) were used to develop a gas sensor paper with detection mechanism based on visible and distinct color changes of the sensor paper when exposed to volatile basic nitrogen compounds. The coating formulation for paper was prepared by applying diatomites, polyvinyl alcohol (PVOH), and pH sensitive dyes on acidic paper substrate. The surface coating was designed to allow a maximum gas flow through the diatomite sensors. The produced sensor paper was tested for sensitivity using different ammonia concentrations and we observed a sensitivity lower limit at 63 ppm. As a comparison, the results show comparable sensitivity levels to carbon nanotube based sensor technologies reported in literature. [ABSTRACT FROM AUTHOR]

This study investigates the antibacterial properties of the natural oil from Copaifera multijuga which was embedded in bio-based materials, to be used in active packaging applications. For this purpose, the naturally extracted copaiba oil was first characterized by gas chromatography and thermogravimetry. Its antibacterial properties were evaluated and confirmed against gram-positive bacteria ( Bacillus subtilis ). The copaiba oil was incorporated into two bio-based materials: (i) paper and (ii) poly(lactic acid), PLA, films. This incorporation was made following two strategies: either at the surface, thanks to a coating process, or in the bulk, through impregnation (paper samples) or by film casting (PLA films). The antibacterial tests confirmed activity against B. subtilis in paper with a copaiba oil content of approximately 20 wt%. For the PLA films, the same amount showed satisfactory results against the same bacteria. To the best of our knowledge, it is the first time that copaiba oil has been incorporated on paper sheets and plastic films, with the confirmation of the maintenance of the effective antibacterial properties. The materials developed in this work through simple procedures have great perspective to be used as biodegradable packaging with bactericide effect, to improve the shelf life of food products. [ABSTRACT FROM AUTHOR]

In most municipalities in India, the collection, transportation and disposal of municipal solid waste deviates from the mass flow envisaged by the municipal agencies and planning authorities. While multiple studies have focused on the environmental problems arising due to uncontrolled waste dumping and combustion, we present a qualitative study of the efforts towards resource conservation and recycling by various actors involved, and a quantitative estimate of the amount of material recovered at various stages. Both the informal sectors (garbage collectors, waste pickers, waste dealers, small stores and itinerant merchants) and the households in India, play a vital role in recovering consumer waste. In order to have an in-depth understanding, a case study has been performed to better understand the contribution of households, garbage collectors and itinerant waste merchants towards recovering consumer waste. Our study shows that consumer waste is far more efficiently recovered in India than what has been reported in literature until now. The waste recovery takes place in multiple-stages and the final waste that reaches the municipal corporation mostly comprises of biodegradable waste, inerts and highly non-recyclable waste. Households, itinerant waste merchants and garbage collectors in India jointly recover 1.2–2.4 million tonnes of newspapers, 2.4–4.3 million tonnes of cardboard and mixed paper, 6.5–8.5 million tonnes of plastic, more than1.3 million tonnes of glass, more than 2.6 million tonnes of metal waste and 4–6.2 million tonnes of other recyclable material per year. Overall, 30–60% of all paper and cardboard, 50–80% of all plastic and close to 100% of all glass bottles produced in India are recycled. [ABSTRACT FROM AUTHOR]

Gaseous acetic acid is formed under conditions of storage of historic paper objects. Its presence not only promotes hydrolytic cleavage of cellulose, but also causes acetylation of the cellulosic material to very small degree. The acetylation reaction proceeds under ambient conditions and without catalyst. Different analytical methods were used to prove the presence of organic acetates on cellulosic paper matrices. DESI-MS in combination with 2H-isotopic labeling showed the presence of sugar fragments with different acetylation patterns. A method based on Zemplen saponification was applied and worked also in the presence of a large excess of acetic acid and/or inorganic acetates. The acetylation effect was quantified for model papers and original, naturally aged paper samples. While cellulose acetylation was clearly proven to be another general pathway of paper aging, further studies of this acetylation phenomenon are needed with regard to conservational aspects and suitable paper storage conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

COVID-19 is a highly diffuse respiratory infection caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). Currently, quantitative real-time polymerase chain reaction (qRT-PCR) technology is commonly used in clinical diagnosis of COVID-19. However, this method is time-consuming and labor-intensive, which is limited in clinical application. Here, we propose a new method for the ultrasensitive and visual detection of SARS-CoV-2 viral nucleic acid. The assay integrates with a paper device and highly efficient isothermal amplification technology - Netlike rolling circle amplification (NRCA), which can reach a limit of detection of 4.12 aM. The paper-based NRCA owns advantages of specificity, portability, visualization and low-cost. Therefore, this method can effectively meet the requirements of point-of-care testing, providing a novel molecular detection technology for clinical diagnosis of COVID-19 and promoting the development of NRCA devices. [Display omitted] ● A paper biosensor was used for ultrasensitive and visual detection of SARS-CoV-2. ● Amplified analysis has been achieved by netlike rolling circle amplification. ● The paper-based NRCA owns advantages of portability, visualization and low-cost. ● The assay can effectively meet the requirements of point-of-care diagnosis of COVID-19. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the feasibility of using highly filled powders with 100 parts per weight of calcium carbonate and 10 parts per weight of polymer, acting as binder, as electrostatically applied paper coatings. Such powders prepared by different methods were evaluated as being suitable for electrostatic coating. Powders compacted at elevated temperatures demonstrated cohesion superior to that of calcium carbonate, and at best similar to that of aqueous coatings. Cohesion, porosity and thus absorption properties of compacted powders were affected by the powder preparation method, compaction process, and powder composition. Powders containing semicrystalline polymer turned out to be the most interesting for further testing. [ABSTRACT FROM AUTHOR]

In this study we investigated the underlying mechanisms of coffee stain formation on paper – a porous substrate. When a drop of aqueous liquid containing dispersed materials dries on paper, the faster water evaporation rate at the edge of the drop drives the redistribution of the dispersed materials to the edge of the drop-covered area on paper. Deegan׳s discovery has been accepted as the “coffee ring” phenomenon, which has wide implications. However, stains left by dried aqueous liquids on paper are not always ring-shaped. This is because, besides Deegan׳s coffee ring effect, the transport of dispersed materials in porous media is affected by chromatographic and filtration effects, which are highly dependent upon the properties of the substrates. In this work we clarify the influences of different mechanisms to the dispersed materials redistribution in paper. [ABSTRACT FROM AUTHOR]

Monodisperse aqueous upconverting nanoparticles (UCNPs) were covalently immobilized on aldehyde modified cellulose paper via reduction amination to develop a luminescence resonance energy transfer (LRET)-based nucleic acid hybridization assay. This first account of covalent immobilization of UCNPs on paper for a bioassay reports an optically responsive method that is sensitive, reproducible and robust. The immobilized UCNPs were decorated with oligonucleotide probes to capture HPRT1 housekeeping gene fragments, which in turn brought reporter conjugated quantum dots (QDs) in close proximity to the UCNPs for LRET. This sandwich assay could detect unlabeled oligonucleotide target, and had a limit of detection of 13 fmol and a dynamic range spanning nearly 3 orders of magnitude. The use of QDs, which are excellent LRET acceptors, demonstrated improved sensitivity, limit of detection, dynamic range and selectivity compared to similar assays that have used molecular fluorophores as acceptors. The selectivity of the assay was attributed to the decoration of the QDs with polyethylene glycol to eliminate non-specific adsorption. The kinetics of hybridization were determined to be diffusion limited and full signal development occurred within 3 min. [ABSTRACT FROM AUTHOR]

An in-plane elasto-plastic material model and a hygroexpansivity-shrinkage model for paper and board are introduced in this paper. The input parameters for both models are fiber orientation anisotropy and dry solids content. These two models, based on experimental results, could be used in an analytical approach to estimate, for example, plastic strain and shrinkage in simple one-dimensional cases, but for studies of the combined and more complicated effects of hygro-elasto-plastic behavior, a numerical finite element model was constructed. The finite element approach also offered possibilities for studying different structural variations of an orthotropic sheet as well as buckling behavior and internal stress situations under local strain differences. A few examples are presented of the effect of the anisotropy and moisture streaks under stretching and drying conditions on strain differences and buckling. The internal stresses were studied through a case in which the drying of different layers occurred at different stages. Both the anisotropy and moisture streaks were capable of rendering the buckling of the sample visible. The permanency of these defects highly depends on several process stages and tension conditions of the sheet, as demonstrated in this paper. The application possibilities of the hygro-elasto-plastic model are diverse, including investigation into several phenomena and defects appearing in drying, converting and printing process conditions. [ABSTRACT FROM AUTHOR]

Lignocellulosic crops like kenaf, flax and hemp have been extensively studied the last years with the help of new technology and many new products fabricated with them are ready for the market or have already been marketed. Both the core material and the bast fibers of these crops are ideal feedstocks for the production of yarns and paper of high quality, for rendering flame retardant properties to composites reinforced with them, for the production of energy via a sustainable way without polluting the environment and for use as alternative materials to wood for the manufacturing of panels like particleboards and fiber boards (MDF, HDF, etc.). The investigation of lignocellulosic feedstock as potential source for the sustainable production of materials, products and energy has resulted in promising solutions for the successful replacement of their counterparts made from fossil raw materials. However, the related industries still have some challenges to face, like the cost of materials from lignocellulosic plants in comparison with those derived from fossil sources and the availability of the feedstock throughout the year. [ABSTRACT FROM AUTHOR]

Six tonnes of discards and recyclables from three waste districts in a New York suburb were sorted in 2012. The districts were chosen because one had a higher recycling percentage, one had median performance, and one was a low performing district. ASTM standards were followed for the waste composition sorting. The results showed, as expected, that the waste district with the highest recycling rate appeared to have the highest separation efficiencies, leading to greater amounts of recyclable materials being source separated. The waste districts also had different overall waste generation, both in terms of the amounts of wastes generated, and their composition. The better recycling district generated less waste, but had a higher percentage of recyclables in the waste stream. Therefore, in some sense, its waste stream was enriched in recyclables. Thus, although the residents of that district recovered materials at a higher rate, they also left large amounts of recyclables in their discards – as did the residents of the other districts. In fact, the districts only recycled between one quarter and less than half of all available recyclables, so that their discards were comprised of up to one third recyclable materials. This level of performance does not appear to be unique to this Town; therefore, we believe that additional recovery efforts through post-collection sorting for recyclables may be warranted. [ABSTRACT FROM AUTHOR]

This article explores the application of DNA computing in recyclable waste paper sorting. The primary challenge in paper recycling is to obtain raw materials with the highest purity. In recycling, waste papers are segregated according to their various grades, and these are subjected to different recycling processes. Highly sorted paper streams facilitate high quality end products, while saving on processing chemicals and energy. In the industry, different sensors are used in paper sorting systems, namely, ultrasonic, lignin, gloss, stiffness, infra-red, mid-infra red, and color sensors. Different mechanical and optical paper sorting systems have been developed based on the different sensors. However, due to inadequate throughput and some major drawbacks related to mechanical paper sorting systems, the popularity of optical paper sorting systems has increased. The automated paper sorting systems offer significant advantages over the manual systems in terms of human fatigue, throughput, speed, and accuracy. This research has two objectives: (1) to use a web camera as an image sensor for the vision system in lieu of different sensors; and (2) to develop a new DNA computing algorithm based on the theme of template matching techniques for segregating recyclable waste papers according to paper grades. Using the concepts of replication and massive parallelism operations, the DNA computing algorithm can efficiently reduce the computational time of the template matching method. This is the main strength of the DNA computing algorithm in actual inspections. The algorithm is implemented by using a silicon-based computer to verify the success rate in paper grade identification. [ABSTRACT FROM AUTHOR]

Paper, a cheap and ubiquitous material, has great potential to be used as low-cost, portable and biodegradable platform for chemical and biological sensing application. In this paper, we are exploring a low-cost, flexible and reliable method to effectively pattern paper for capturing optical dyes and for flow-based delivery of target samples for colorimetric chemical sensing. In this paper, we target the detection of ammonia (NH 3 ) and carbon dioxide (CO 2 ), two of the important environmental and health biomarkers. By functionalizing the paper platform with diverse cross-reactive dyes sensitive to NH 3 and CO 2 , their selective sensing within a certain pH range, as well as their detection at different concentrations can be achieved. The images of paper based device were captured by a flatbed scanner and processed in MATLAB ® using a RGB model and PCA for quantitative analysis. Paper based devices with readout using ubiquitous consumer electronic devices (e.g. smartphones, flatbed scanner) are considered promising approaches for disease screening in developing countries with limited resources. [ABSTRACT FROM AUTHOR]

Most spectroscopic studies of the reaction products formed by ninhydrin, 1,2-indanedione-zinc (Ind- Zn) and 1,8-diazafluoren-9-one (DFO) when reacted with amino acids or latent fingermarks on paper substrates are focused on visible absorption or luminescence spectroscopy. In addition, structural elucidation studies are typically limited to solution-based mass spectrometry or liquid nuclear magnetic resonance (NMR) spectroscopy, which does not provide an accurate representation of the fingermark development process on common paper substrates. The research presented in this article demonstrates that solid-state carbon-13 magic angle spinning NMR (13C-MAS-NMR) is a technique that can not only be utilised for structural studies of fingermark enhancement reagents, but is a promising technique for characterising the effect of paper chemistry on fingermark deposition and enhancement. The latter opens up a research area that has been under-explored to date but has the potential to improve our understanding of how fingermark secretions and enhancement reagents interact with paper substrates. [ABSTRACT FROM AUTHOR]

We describe a low cost optical temperature sensor that is simple to manufacture. The sensor is constructed by simple soaking of paper in a solution of the temperature sensitive luminescent indicator Ru(phen) 3 and subsequent lamination of the dried paper. Lamination prevents O 2 diffusion to the indicator and thus eliminates O 2 cross-sensitivity. The temperature sensitivity was up to −2% change in luminescence lifetime per K, a t 90 response time of 10 s. Besides luminescence lifetime based measurements, the sensor is well suited for ratiometric imaging with simple RGB cameras, where the temperature dependent red luminescence can be referenced by the blue luminescence of the optical brightener in the paper. [ABSTRACT FROM AUTHOR]

In order to examine the potential efficacy of simultaneous dual-species fungal treatment of wood for lignocellulosic ethanol production, whole organism fungal biopulping methods utilizing white rot ( Ceriporiopsis subvermispora ) and brown rot ( Postia placenta ) fungi alone or in co-culture were compared for effect on wood microstructure, chemical composition, and enzymatic sugar solubilization. Liriodendron tulipifera wood chips exposed for 30 days to C . subvermispora and/or P . placenta fungi alone or in co-culture exhibited qualitative differences in wood microstructure, but did not significantly differ in final percent composition of holocellulose, α -cellulose, or lignin content compared to controls. All fungal treatments increased the soluble reducing sugar yield of enzymatic hydrolysis by ca. 28–30% over sterile controls. The co-culture fungal treatment did not significantly differ in reducing sugar yield compared to monoculture treatments, suggesting an unexpected lack of additive or other synergistic species effects on wood degradation using these fungi in co-culture. Paired interaction agar plate assays demonstrated that C . subvermispora and P . placenta exhibited mutual distance-mediated growth inhibition that was independent of substrate type or availability, suggesting an explanation for the observed lack of degradative synergy between these taxa. This study is the first to report the effects of simultaneous co-treatment with white and brown rot fungi, highlights the need for further optimization of methods to account for specialized fungal degradative mechanisms, and examines the potential influence of competitive interactions in whole-organism biopulping treatments utilizing different taxa. [ABSTRACT FROM AUTHOR]