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The purpose of the research was to measure the increase in the binding of inclusion complexes β-cyclodextrin-peppermint oil (β-CD_PM) to cellulose in cotton and cotton/polyester material with BTCA as the crosslinking agent by applying an ultrasonic bath at room temperature and a frequency of 80 kHz for 10 min. After sonication, the samples were left in a bath for 24 h after which they were dried, thermocondensed and subjected to a number of wash cycles. The treated samples were analysed with Attenuated total reflection (ATR) units heated up to 300 °C (Golden Gate (FTIR-ATR)) to monitor chemical changes indicative of crosslinking, while physico-chemical changes in the samples were monitored by using Fourier transform infrared spectroscopy (FTIR-ATR). Mechanical properties were measured according to EN ISO 13934-1:1999, and coloristic changes were evaluated by the whiteness degree according to CIE (WCIE) and the yellowing index (YI), while antimicrobial activity was determined according to AATCC TM 147-2016. The results show a physico-chemical modification of the UZV-treated cellulosic material. Moreover, partial antimicrobial efficacy on Gram-negative bacteria was confirmed for treated fabrics.

Active pumps are often used in microfluidic devices for programmable fluid flowrate in a microchannel. Active pumps have some drawbacks due to their large size and requirement of external power. To overcome them, a new class of passive pumps based on capillary action in cellulose material, known as paper-based microfluidic pumps, has recently been explored. In this study, fluid flow in 3D paper-based pumps was investigated using flowrate measurements in microchannels. In order to develop 3D cylindrical pumps, Whatman filter paper grade 1 was shredded, mixed with water, molded and dried. The patterned serpentine channel was created using a CO2 Laser Cutting/Engraving machine. The 3D paper-based pump was integrated with microfluidic channel. The effect of paper pumps of different porosities on the fluid flowrate through a serpentine microchannel was investigated. It was found that flowrate of the fluid flowing through the channel increases with an increase in the pump’s porosity. Moreover, these pumps have the ability to transport larger volumes of liquid with improved flowrate, programmability and control, in addition to being inexpensive and simple to design and fabricate. These 3D pumps will help researchers move closer to developing an effective miniaturized diagnostic platform for point-of-care (POC) diagnostic applications.

This review describes the methods of cellulose amorphization, such as dry grinding, mercerization, treatment with liquid ammonia, swelling in solvents, regeneration from solutions, etc. In addition, the main characteristics and applications of amorphized celluloses are discussed. An optimal method for preparing completely amorphous cellulose (CAC) via the treatment of original cellulose material with a cold NaOH/Urea-solvent at the solvent to cellulose ratio R ≥ 5 is proposed. Structural studies show that amorphous cellulose contains mesomorphous clusters with a size of 1.85 nm and specific gravity of 1.49 g/cm3. Furthermore, each such cluster consists of about five glucopyranose layers with an average interlayer spacing of 0.45 nm. Amorphous cellulose is characterized by increased hydrophilicity, reactivity, and enzymatic digestibility. Due to its amorphous structure, the CAC can be used as a promising substrate for enzymatic hydrolysis to produce glucose, which can be applied in biotechnology for growing various microorganisms. In addition, the application of CAC in agriculture is described. A waste-free method for producing amorphous nanocellulose is considered, and the main applications of nanosized amorphous cellulose are discussed.

AbstractIn recent years, electroactive paper emerged as a new alternative in the field of smart actuators. It is based on a cellulose material which is able to bend under the influence of an external electric field similarly as ionic polymer metal composites. The bending mechanism is mainly attributed to the migration of ionic charges over the thickness of a thin sheet of paper. The present contribution proposes a numerical framework for the simulation of electroactive paper. It is based on a scaled boundary plate formulation for isogeometric analysis. In contrast to the standard scaled boundary plate approach, the scaling direction is solved numerically by a B-Spline approximation. This allows to render nonlinear effects over the plate thickness as well as displacement fields of higher continuity. The model is applicable to very thin structures such as electroactive paper, and it also captures the nonlinear ionic charge distribution which is coupled to the bending mechanism of the actuator.

Background: The synthesis of 5-arylation uracil nucleosides is an imperative challenge. Especially for the method of suzuki reaction using N-unprotected uracil as materials, which holds potential to enhance the yield. Objective: In order to find a more efficient catalyst to increase the yield of aryluracils and aryluridines. Methods: We first constructed the phosphanamine-grafted cellulose (PAGC) from cellulose material. And then prepared the nanocatalyst PAGC/Pd(0) through heating and reducing the mixture of PAGC and Pa(OAc)2. Results: When using this nanocatalyst to catalyze the Suzuki reaction of 5-iodouracil or 5-iodouridine and aryl heterocyclic boronic acids. The arylation yields have been a significantly improvement. Conclusion: This means that the resultant nanocatalyst exhibits a remarkable catalytic efficacy for Suzuki arylation of 5-iodouracil and 5-iodouridine.

This work reports a modification of a fibrous cellulose material (paper) by the addition of polyacrylonitrile (PAN) fibres doped with 10,12–pentacosadiynoic acid (PDA). The fibres are sensitive to ultraviolet (UV) light. When the paper containing PAN–PDA is irradiated with UV light it changes colour to blue as a consequence of interaction of the light with PDA. The colour intensity is related to the absorbed dose, content of PAN–PDA fibres in the paper and the wavelength of UV radiation. The features of the paper are summarised after reflectance spectrophotometry and scanning microscopy analyses. All the properties of the modified paper were tested in accordance with adequate ISO standards. Moreover, a unique method for assessing the unevenness of the paper surface and the quality of printing was proposed by using a Python script (RGBreader) for the analysis of RGB colour channels. The modification applied to the paper can serve as a paper security system. The modified paper can act also as a UV radiation indicator.

Abstract Absorbable oxidized cellulose hemostatic materials are widely used in hemostasis of veins, capillaries or smaller arteries because of their wide sources, low cost, and high biocompatibility. However, in view of the different application sites, the hemostatic effect of absorbable oxidized cellulose in different surgeries may be different, and its hemostatic effect in patients with colorectal cancer still needs more research to confirm. Therefore, this article explores the in vitro degradation of the absorbable regenerated oxidized cellulose material and its hemostatic effect in colorectal cancer surgery. Explore the in vitro degradation products that can absorb oxidized cellulose. The 44 patients undergoing colon cancer surgery were selected and randomly divided into control group (22 cases, absorbable oxidized cellulose material to stop bleeding) and observation group (22 cases, ordinary Sterile gauze to stop bleeding). The intraoperative blood loss, 3 days postoperative drainage volume, total drainage volume, and operation time of the two groups were recorded. The recovery of intestinal function after operation in the two groups was observed. The in vitro complete degradation time of the absorbable oxidized cellulose material is about 12 days. The degradation products are glucose and cellobiose, which are safe and harmless to the human body. The intraoperative blood loss, drainage volume, total drainage volume, and operation time of the observation group were significantly lower than those of the control group (P <0.05), and the postoperative intestinal function recovery of the observation group was better than that of the control group (P <0.05). In addition, there was no significant difference in the incidence of adverse reactions between the observation group and the control group (P > 0.05). Absorbable oxidized cellulose material has a good hemostatic effect in colorectal cancer surgery, and does not increase the risk of adverse reactions in patients after surgery. It is worthy of popularization and application.

Abstract Vulcanized fiber is an all-cellulose material made from cotton and/or wood cellulose after zinc chloride treatment. This material was invented in the UK in the mid-19th century and is used because of its excellent characteristics, such as impact resistance and electrical insulation. Recent research revealed that the vulcanized fiber strength can be attributed to the chemically defibrillated cellulose nanofibers. In this report, we describe the history and structural characteristics of vulcanized fibers and introduce a new aspect of zinc chloride treatment.

The search for sustainability has led to the utilization of more ecological materials with at least, a similar structural performance to those used at present. In this regard, reed fits the environmental and structural requirements as it is a sustainable and biodegradable lignin-cellulose material with remarkable mechanical properties. This research confirms the reed’s structural efficiency as it demonstrates that it has excellent strength and stiffness in relation to its density. The reed anisotropy has a large impact on its properties. Indeed, the strength and stiffness parallel to the fibers are clearly higher than in the perpendicular direction. The results confirm that strength and stiffness decrease with the moisture content and nodes act as reinforcement in compression and bending. If compared with steel, timber and concrete, the reed possesses the highest value for strength. Hence, reed constitutes a strong candidate for environmentally friendly engineering.