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Incorporation of nanofillers into a polymeric matrix has received much attention as a route to reinforced polymer nanocomposites. In the present work, an environmentally friendly chitosan (CTS)/titanium dioxide (TiO2) nanocomposite coating was designed/prepared and subsequently employed for imparting antibacterium and improved mechanical properties to cellulosic paper via surface coating. Effect of TiO2 nanoparticle loadings on the rheological behavior of nanocomposite coatings was investigated. Surface application of CTS/TiO2 nanocomposite coatings to cellulosic paper was performed, and the antibacterial activity and mechanical properties of surface-coated cellulosic paper were examined. Results showed that the increased TiO2 nanoparticle loadings decreased the viscosity and dynamic viscoelasticity of the as-prepared coatings, and improved the antibacterial activity and mechanical properties of surface-coated cellulosic paper. The optimum loading of TiO2 nanoparticles was identified at 10%. This work suggested that CTS/TiO2 nanocomposite coatings may have the potential to be used as a promising antibacterial protective coating for paper packaging., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Flow monitoring in porous materials is critical for the engineering of paper-based microfluidic bioassays. Here, we present an electrochemical-sensor system that monitors the liquid flow in porous materials without affecting the real flow in paper-strip samples. The developed microfluidic sensor records an amperometric signal created by the solution movement mediated by paper wicking. This approach allows the in situ monitoring of the different hydrodynamic conditions of a specific paper geometry or composition. In addition, the method proposed in this work was employed to characterise the fluid flow of different nitrocellulose paper strips after oxygen-plasma treatment or dextran coating. The dextran fluid-flow modifiers were further used on the paper strip-based assays as means of signal enhancement. The proposed electrochemical-sensing method offers a valuable alternative to existing optical-based monitoring techniques for flow measurement in paper-based microfluidic systems., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In heritage conservation, paper deterioration can be slowed down by controlling the environmental conditions surrounding heritage objects and stabilizing the materials these objects are made of. As conservation materials can also cause optical, chemical, and physical changes in the object, their application should be safe, minimalistic, and purposeful. This paper aimed to observe the functional applications of three biopolymers used in paper conservation. For that purpose, a model paper was coated with methylcellulose (MC), cellulose nanocrystals (CNCs), and wheat starch (WSP) using different wet film deposits. The prepared samples were characterized by determining their physical, optical, and surface properties. The results show that changes in the wet film deposit thickness influenced paper properties. With CNCs, the increase has caused a drastic change of colour properties, with MC hydrophobicity increased and with WSP grammage and thickness increased. All coatings (except CNC24) have contributed to the preservation of the colour properties of the paper from the damage caused by thermal ageing. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Exploring cellulolytic secretome is a promising strategy to produce a cost-effective enzyme preparation for biorefinery of lignocellulosic waste. In this study, a fungal secretome from Talaromyces sp. BRG1 was produced with pretreated sugarcane bagasse (SCB) as the inductive substrate. Hydrolysis capacity of BRG1 secretome and commercial enzyme Cellic® Ctec2 were compared on SCB and then applied to paper pulp (PP). Normalised activity profile of cocktails based on filter paper unit activity (FPU) indicated that BRG1 secretome exhibited a higher endo-glucanase (CMCU, × 4.4) and endo-xylanase activities (EnXU, × 1.6) but lower avicelase (AVCU, /8.4) and cellobiase (CBU, /3.4) activities. Lignocellulolytic cocktails were examined on SCB as reference before applied on PP at 3% w/v solid loading in batch mode for 24 h. For both substrates and enzyme loading ratio (0.3 and 3.0 FPU/g cellulose), the glucose yield by BRG1 secretome was 2 times higher than Cellic® Ctec2. In-situ viscometry confirmed the quicker liquefaction efficiency of secretome over Ctec2. At 0.3 FPU/g cellulose, the suspension viscosity of PP collapsed completely after 12 h with BRG1 secretome whereas a limited reduction to 44% was observed with Ctec2. Ex-situ particle size distribution revealed a stronger reduction of coarse and fine particles with BRG1 secretome compared to Ctec2. • Production of a substrate-specific cellulolytic secretome from Talaromyces sp. BRG1. • Comparison of secretome efficiency by normalizing activities based on FPU. • Combining morphological, rheological, and biochemical methods to assess hydrolysis. • Observation of high hydrolysis and liquefaction rates at low enzyme loading. • Validation of BRG1 secretome with paper pulp and pretreated sugarcane bagasse. [ABSTRACT FROM AUTHOR]

Simple Summary: Blood clots are formed when blood vessels are injured. They help stop bleeding and heal wounds, but can also cause serious problems if they block blood flow or break off and travel to other organs. This study investigates how blood clots differ in people with cancer compared to healthy or non-cancerous individuals. This study found that cancer patients have higher levels of histones in their blood, which make their clots stiffer and resistant to lysis. Further, clots formed in cancer patients have higher viscoelastic properties, and hence are harder to break down. These findings suggest that cancer patients have abnormal clotting properties that may increase their risk of developing thrombosis, and evaluating these properties can be helpful in detecting cancer. Background: Blood viscoelasticity and plasma protein levels can play an important role in the diagnosis and prognosis of cancer. However, the role of histones and DNA in modulating blood clot properties remains to be investigated. This study investigates the differences in blood viscoelasticity and plasma protein levels among cancer patients, individuals with other diseases, and healthy individuals. Methods: Blood samples were collected from 101 participants, including 45 cancer patients, 22 healthy individuals, and 34 individuals with other diseases. Rheological properties of clots formed in vitro by reconstituted elements of fibrinogen or plasma were analyzed with an Anton Paar Rheometer, USA. Plasma protein levels of D-dimer, TPA, EPCR, fibrinogen, and histone H3 were measured through ELISA. Blood clots were formed with or without DNA and histones (H3) by adding thrombin and calcium to plasma samples, and were evaluated for viscoelasticity, permeability, and degradation. Results: Cancer patients show higher blood viscoelasticity and plasma D-dimer levels compared to healthy individuals and individuals with other diseases. Our in vitro analysis showed that the addition of histone to the plasma results in a significant decrease in viscoelasticity and mean fiber thickness of the clot formed thereafter. In parallel studies, using plasma from patients, DNA and histones were detected in fibrin clots and were associated with less degradation by t-PA. Moreover, our results show that the presence of DNA and histones not only increases clots' permeability, but also makes them more prone to degradation. Conclusions: Plasma histones and DNA affect the structure of the clot formed and induce defective fibrinolysis. Moreover, the increased viscoelastic properties of plasma from cancer patients can be used as potential biomarkers in cancer prognosis. [ABSTRACT FROM AUTHOR]

• Oxidation and flocculation presented a significant synergistic effect. • Flocculation promoted the transformation of bound EPS to S-EPS after oxidation treatment. • Flocculation played a more important role than Oxidation in the combined conditioning. • The decrease of bound water contents and enhancement of flocs strength were the major mechanism of sludge dewaterability. [Display omitted] Due to the high hydrophilicity of extracellular polymeric substances (EPS) and colloidal property of sludge solids, applying efficient methods has attracted much attention for enhancing sludge dewatering. The oxidation and following flocculation of paper activated sludge is usually used alone or in combined conditioning with other pretreatments for sludge dewatering deeply. However, few studies are reported on the systematic comparison and role positioning of oxidation and flocculation conditioning. The results indicated that the sludge dewaterability of the combined potassium permanganate (KMnO 4) and ferric chloride (FeCl 3) conditioning was enhanced significantly with FeCl 3 dosage decreasing by 75 % compared with individual FeCl 3 conditioning. The mechanism is a synergistic effect of oxidation stripping and flocculation re-construction: larger agglomerated sludge flocs formed, and more bound water was released. FeCl 3 played a more important role than KMnO 4 for sludge dewaterability. The contents of bound water, S-EPS, maximum shear stress, and hysteresis area were the critical factors for sludge dewaterability. These findings provided further understanding of the combined oxidation and flocculation processes for improving dewaterability. [ABSTRACT FROM AUTHOR]

Printing technology for electronic devices has garnered considerable attention owing to its rapid and massive productivity under ambient conditions. In this study, a facile approach is proposed for manufacturing cellulose paper-based strain sensors with Ni/multi-walled carbon nanotube (MWCNT) composites using roll stamping technology. This process enables the fabrication of stable sensing structures owing to the formation of stable Ni core-enveloping structures in the MWCNT interlacing network. In particular, the rheological properties of the composites revealed shear thinning and thixotropic behavior, which resulted in fine printing of the sensing electrodes. Furthermore, the shape of the printed patterns, imparted by the pattern morphology, significantly influenced the strain-sensing performance. In particular, the Ni/MWCNT composite-based strain sensor exhibited a higher gauge factor of 13.9, with a high sensing recovery of 90.4% and stability over 23,500 bending cycles. [ABSTRACT FROM AUTHOR]

In the restoration of ancient Chinese books, handmade starch paste serves as a paper adhesive, distinguished from traditional starch paste preparation methods. It involves special processes such as starch washing and aging, relying entirely on the artisanal expertise throughout the entire process. The study recreates the process of making handmade starch paste for the restoration of traditional ancient books and investigates the effects of aging time on the apparent viscosity, rheological properties, and adhesive performance of the paste. The results indicate that during aging, the pH of the starch paste decreases significantly, but it has a minimal impact on its apparent viscosity, rheological properties, and paper softness. However, it notably enhances the adhesive performance, with the optimal results observed after 3 days of aging. This is attributed to the decrease in residual protein content in the starch, as well as the significant improvement in swelling power and solubility of the starch. The results of infrared spectroscopy and XRD testing reveal that there are no significant changes in the molecular and crystalline structures of starch during the aging process. The acidic environment produced by starch fermentation promotes protein hydrolysis, emerging as the primary reason for the improved adhesive performance of the paste. [ABSTRACT FROM AUTHOR]

The exponentially decaying acoustic pressure of scattered surface acoustic waves (SAWs) at the contact line of a liquid film pinned to filter paper is shown to sustain a high curvature conic tip with micron-sized modulations whose dimension grows exponentially from the tip. The large negative capillary pressure in the film, necessary for offsetting the large positive acoustic pressure at the contact line, also creates significant negative hydrodynamic pressure and robust wicking action through the paper. An asymptotic analysis of this intricate pressure matching between the quasistatic conic film and bulk drop shows that the necessary SAW power to pump liquid from the filter paper and aerosolize, expressed in terms of the acoustic pressure scaled by the drop capillary pressure, grows exponentially with respect to twice the acoustic decay constant multiplied by the drop length, with a universal preexponential coefficient. Global rapid aerosolization occurs at a SAW power twice as high, beyond which the wicking rate saturates.

Copyright of Fibres & Textiles in Eastern Europe is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An approach is demonstrated for the manufacturing of a microfibrillated cellulose (MFC) composite paper. A key element in the manufacturing paradigm is the use of high consistency suspensions to improve retention and minimize the need for water removal after forming. The rheological characterization of the composite furnish, which contained 70% structured pigment, 20% MFC, and 10% pulp fibers, revealed a gel-like shear thinning behavior of the suspension, which differs greatly from traditional fiber-based papermaking furnishes. The results from laboratory and pilot scale studies show that the headbox consistency range from 5 to 10% offers the best combination of processing, forming characteristics, retention, and dewatering. While the furnish dewatering in laboratory scale was very problematic, under suitable dynamic conditions the wire section dewatering was excellent. The results of this study suggest that the MFC composite can be manufactured on a modified paper machine and that the final product will have an attractive cost structure.

Chemical upcycling of plastic waste from landfills to value-added products offers both economic and environmental benefits. Reported here is a simple method to convert high-density polyethylene (HDPE) into upcycled waxes in a very high yield (up to 93%). This selectivity is achieved by reducing the degradation temperature of HDPE via the addition of an inexpensive and reusable sodium chloride. These upcycled waxes had performance comparable to those of commercial rheology modifiers. In addition, kraft paper coated with these upcycled waxes exhibited excellent water- and oil resistance. A preliminary revenue analysis showed that this innovation allows plastic-to-wax to conversion with a three-fold revenue benefit over traditional ways of producing pyrolysis waxes from plastics. Also, sodium chloride reduces the pyrolysis temperature, thus reducing energy consumption and greenhouse gas emissions, supporting cleaner production, a circular economy, and generating less environmental pollution. The underlying concept reported herein can be extended to major plastics by reducing the degradation temperatures of plastics, thereby obtaining even better control over the pyrolysis products. Thus, these findings have the potential to enhance the circular economy of plastics and protect our environment from plastic waste. SYNOPSIS. Chemical upcycling of post-consumer polyethylene via a sodium chloride-catalyzed process. [Display omitted] • Demonstrated table salt-assisted pyrolysis of high-density polyethylene. • Converted polyethylene into upcycled waxes at mild temperatures and in high-yield. • Used upcycled waxes as rheology modifiers and water-proof coating material. • Performed preliminary revenue analysis. [ABSTRACT FROM AUTHOR]

The major benefits of using polymers based EOR include an increase of viscosity of the injected water, increasing sweep efficiency, and reduction in mobility ratio. A variety of polymers are available in the market, yet every polymer is unusable for any field, thus posing selection and how to use challenges in novel EOR technology. This paper focuses on the screening of polymer based on filtration ratio and rheological tests. The Filtration Ratio (FR) test of the polymer solutions has been investigated to check the hydration properties of PHPA polymer by passing it through the nitrocellulose filter paper. The results indicated that FR less than 1.2 ensures proper hydration only if the proper size of filter paper is selected and the filter paper should withstand the pressure. Whereas the presence of monovalent ions slightly increases the FR thus causing the formation of early Filter Cake but can still be used only if FR is less than 1.2. These findings may help the industry to compare wide variety of polymers solutions for a specific well. Only those polymers would be used which passes FR test with little or no filter cake for further rheological tests, thus ensuring proper utilization of available time. [ABSTRACT FROM AUTHOR]

This study provides a complete rheological characterization of bidimensional (2D) nanomaterial dispersions, employed as 2D-inks precursors in printed electronics. Three different 2D nanomaterials [molybdenum disulfide (MoS2), graphene, and hexagonal boron nitride (hBN)] were dispersed in a Newtonian fluid (toluene) and a viscoelastic fluid (toluene + ethyl cellulose) with different polymer concentrations. The presence of nanosheets does not change the shear rheology of the carrier fluid. Regarding the extensional rheology, the results showed that the pinch-off phenomenon is present in all toluene suspensions; however, the presence of the ethyl cellulose introduces elasticity in the system, even leading to the formation of beads-on-a-string, and the relaxation times of the suspensions depend on the kind of nanosheets present in the fluid. As controlling the droplet size when dispensing 2D-inks is of paramount importance for printed electronics as well as for many other applications, here it is presented a correlation between the rheological properties of these 2D-inks precursors and their droplet size when generated from a capillary nozzle in the dripping regime. [ABSTRACT FROM AUTHOR]

The oil-separation properties of lubricating greases are responsible for transporting base oil to the bearing contacts. Therefore, a good understanding of these properties is necessary to predict grease life based on physical grease properties. Currently, oil separation for small, aged grease samples collected from bearings, is studied using so-called maintenance tools. These tools give qualitative insight into the grease properties, e.g., increases or decreases in oil separation after ageing of the grease. In this work, a quantitative, lab-scale method to study oil separation is presented. Using this method, the amount of base oil transferred from a grease sample to a piece of blotting paper is measured based on the difference in light transmission through the oil stain and the dry paper. Translation of transmitted light intensity to oil concentration is accomplished using a modified Lambert-Beer’s law. This enables the determination of the instantaneous bleed rate and oil content. In combination with a physical model, this method can help to improve the understanding of the driving forces behind oil separation, e.g., the affinity pressure and permeability. [ABSTRACT FROM AUTHOR]