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In an article to study the effect of sizing agent and filler on the structural features of paper from the cellulose mass of the inner layer of the bark of mulberry tree branches, mechanical strength, absorbency and sorption properties were studied. Tensile strength was determined on a tensile testing machine by the force causing the destruction of the sample. Surface absorbency at one side wetting was determined by the method of Cobb(30), by determining the mass of water absorbed by the surface of the paper when wetting one side of the test sample. Sorption properties were studied on a high-vacuum setup with mercury gates and McBain quartz balances according to water vapor sorption data. It was found that the internal 2% sizing of the paper pulp with cherry tree resin glue contributes to the strengthening of the paper structure, which is confirmed by the values of mechanical strength and surface absorbency when unilaterally wetted with water, relative to the values obtained when sizing with pine oleoresin rosin glue. When using glue from cherry resin, it is advisable to add 2 g of kaolin to 100 g of pulp from the inner layer of the bark of mulberry tree branches, since the increase negatively affects mechanical strength and hydrophobicity., В статье для исследования влияния проклеивающего вещества и наполнителя на структурные особенности бумаги из целлюлозной массы внутреннего слоя коры веток тутового дерева изучены механическая прочность, впитывающая способность и сорбционные свойства. Прочность на разрыв при растяжении определяли на разрывной машине по усилию, вызывающему разрушение образца. Поверхностную впитываемость при одностороннем смачивании определяли по методу Кобб(30), путем определения массы воды, поглощенной поверхностью бумаги при смачивании одной стороны испытуемого образца. Сорбционные свойства исследовали на высоковакуумной установке с ртутными затворами и кварцевыми весами Мак-Бена по данным сорбции паров воды. Выявлено, что внутренняя 2%-ная проклейка бумажной массы клеем из живицы черешневого дерева способствует упрочнению структуры бумаги, что подтверждается значениями механической прочности и поверхностной впитываемостью при одностороннем смачивании водой, относительно значений, полученных при проклейке канифольным клеем из сосновой живицы. При использовании клея из живицы черешневого дерева целесообразно к 100 г целлюлозной массы из внутреннего слоя коры веток тутового дерева добавлять каолин в количестве 2 г, так как увеличение отрицательно влияет на механическую прочность и гидрофобность.

The use of natural nanocomponents for increasing the mechanical strength of paper in the aerodynamic method has been investigated. Milled bacterial cellulose and a fine fraction of sulphate bleached softwood cellulose formed during grinding (secondary fines) were used as nanocomponents. The treatment with nanocomponents was carried out while moistening the fibrous layer with the use of an anti-adhesive material providing uniform one sided application of substances in the form of a suspension on the paper surface. The growth of the indicators of the mechanical strength of paper occurred due to the formation of additional hydrogen bonds and an increase in the interfacial interaction between the fibrous layer of plant cellulose and the nanocomponent. It was found that the use of a suspension of bacterial cellulose is more promising due to the low consumption of the binder with a significant increase in the mechanical strength of the paper. The application of a bacterial cellulose coating layer on aerodynamically molded eucalyptus cellulose makes it possible to increase the mechanical strength of the paper to consumer requirements with the consumption of bacterial cellulose in an amount of 0.9% to 1.5% by weight of absolutely dry eucalyptus cellulose., Исследовано применение природных нанокомпонентов для повышения механической прочности бумаги при аэродинамическом способе формования. В качестве нанокомпонентов использовали измельченную бактериальную целлюлозу и мелкую фракцию сульфатной беленой хвойной целлюлозы, образующуюся в процессе размола (вторичную мелочь). Введение нанокомпонентов проводили при увлажнении волокнистого слоя с применением антиадгезионного материала, обеспечивающего равномерное одностороннее нанесение веществ в виде суспензии на поверхность бумаги. Рост показателей механической прочности бумаги происходил за счет образования дополнительных водородных связей и возрастания межфазного взаимодействия между волокнистым слоем из растительной целлюлозы и нанокомпонентами. Установлено, что использование суспензии бактериальной целлюлозы более перспективно из-за малого расхода при значительном повышении показателей механической прочности бумаги. Нанесение покровного слоя бактериальной целлюлозы на бумагу аэродинамического формования из сульфатной беленой эвкалиптовой целлюлозы позволяет повысить значение механической прочности бумаги до потребительских требований при расходе бактериальной целлюлозы в количестве от 0.9 до 1.5% к массе абсолютно сухой целлюлозы.

This manuscript aimed to enhance the mechanical, thermal, and ignition properties of bagasse paper when coated with different coatings synthesized from hydroxyethyl cellulose, 1,3-di-p-toluidine-2,2,2,4,4,4-hexachlorocyclodiphosph(V)azane, Talc powder, NaHCO3, cellulose nanocrystal. The effect of these coatings on the mechanical properties was studied by measuring elongation, tensile strength, and burst strength. The stages of degradation and ash residue of the measuring specimens were determined using thermal gravimetric analysis (TGA), behind that, the ignition properties as the flame chamber (UL/94), and limiting oxygen index (LOI) was measured according to standards. These tests proved that 1,3-di-p-toluidine-2,2,2,4,4,4-hexachlorocyclodiphosph(V)azane has a direct effect on improving the mechanical characteristics and enhancing the ignition properties of the coated specimens compared to uncoated. In this study the physical, mechanical, thermal, and ignition properties of the bagasse paper sheets were enhanced by easy and low-cost method via synthesis of new coatings based on commercially available chemicals in a reasonable cost.

The aim of this study was to investigate the effect of using whey powder (different concentrations and treatment repetitions) as a probiotic agent on the quantitative and qualitative properties of stored bagasse intended for use in the pulp and paper industry. For this purpose, whey powder was added in three concentrations and the treatment was applied once or twice. After that, soda pulp was prepared under conventional conditions. Then, handsheets (80 g/m2) were made and tested in terms of paper properties, and the results were compared. The findings revealed that increasing the concentration of whey powder and the number of treatments significantly improved the pulp and paper characteristics, thus, using the treatment with 2% whey powder twice and 0.4% whey powder once led to the best results for bagasse protection in terms of quality of the raw material, pulp and handsheets.

We employed a microwave-assisted two-pot in-situ deposition technique to incorporate zinc oxide particulates in the structure of filter paper to produce antimicrobial paper. The process involved successive immersion of filter paper samples in ZnSO4 (precursor solution) and NaOH (precipitating agent) to form Zn(OH)2, which transformed into ZnO during microwave treatment. Successful deposition of ZnO particles on the filter paper was confirmed via X-ray diffraction and the corresponding morphologies were observed using field emission scanning electron microscopy. The ZnO-deposited papers were tested for antimicrobial activity and were found to be more effective against Staphylococcus aureus (gram-positive) than Escherichia coli (gram-negative). Bacterial populations were reduced by up to 92 ± 2% and 57 ± 4% for S. aureus and E. coli, respectively. Also, it was found that the samples prepared using higher concentrations of ZnSO4 and NaOH exhibited better antimicrobial properties.

Free-standing flexible supercapacitive electrodes have practical application for wearable energy storage devices. In this paper, graphene paper (GP), a flexible electrode substrate, was prepared by one-step reduction of graphene oxide (GO) using HI solution. GP can be used independently as a flexible electrode with specific capacitance of 227 F/g. In order to make up for the shortage of GP specific capacitance storage, polyaniline (PANI) with high specific capacitance and good electrical conductivity was selected to composite with GP by electrochemical polymerization approach. This method to fabricate electrode material by direct electrochemical polymerization avoids the use of conductive binder and organic solvent. Owing to the specific capacitance contribution of PANI and GP, the PANI/GP composites exhibit higher specific capacitance when the polymerization time is 30 s and the polymerization voltage is 0.8 V. At 1 A/g current density, the specific capacitance of composite is up to 759 F/g, which is 3.34 times of neat GP.

This study aimed to determine the effect of recycling elemental chlorine free (ECF) bleaching effluent (D0EpD1 and OD0EpD1) after treatment through electrocoagulation under optimum conditions on paper properties. The effect of pH, current density, time and dose of electrolyte on the reduction of chemical oxygen demand (COD) and color was studied. Maximum decrease in COD and color was found under optimum conditions (i.e., pH 7, treatment time of 30 min, current density of 29.16 mA/cm2, and 1 g/L NaCl). Under these optimum conditions, the reduction in COD and color was of 79.9% and 99.10%, respectively. The reduction in the strength properties of paper, caused by recycling, was found to be insignificant, but a decline of 2.11% for D0EpD1 and of 1.43% for OD0EpD1 in brightness was found. Using the electrocoagulation method to treat the bleaching effluent can prove to have valuable potential towards wastewater utilization, pollution control, and sustainable development of the industry.

Herein is presented a novel and efficient portable paper-based sensing platform using paper-incorporated histidine stabilized gold nanoclusters (His-AuNCs), for the sensitive and selective detection of Fe ions from low-volume real water samples based on photoluminescence (PL) quenching. Highly photoluminescent colloidal His-AuNCs are obtained via a novel microwave-assisted method. The His-AuNCs-based sensor reveals a limit of detection (LOD) as low as 0.2 μM and a good selectivity towards Fe ions, in solution. Further, the fabricated portable sensing device based on paper impregnated with His-AuNCs proves to be suitable for the easy detection of hazardous Fe levels from real water samples, under UV light exposure, through evaluating the level of PL quenching on paper. Photographic images are thereafter captured with a smartphone camera and the average blue intensity ratio (I/I0) of the His-AuNCs-paper spots is plotted against [Fe2+] revealing a LOD of 3.2 μM. Moreover, selectivity and competitivity assays performed on paper-based sensor prove that the proposed platform presents high selectivity and accuracy for the detection of Fe ions from water samples. To validate the platform, sensing assays are performed on real water samples from local sources, spiked with 35 μM Fe ions (i.e., Fe2+). The obtained recoveries prove the high sensitivity and accuracy of the proposed His-AuNCs-paper-based sensor pointing towards its applicability as an easy-to-use, fast, quantitative and qualitative sensor suitable for on-site detection of toxic levels of Fe ions in low-volume real water samples.

"Moringa oleifera (drumstick) wood was evaluated in terms of its chemical composition, morphological features, Kraft pulping behavior, ECF bleaching and mechanical strength properties – important parameters for pulp and paper making – in comparison with Acacia mangium. Moringa oleifera was found to have the following composition: holocellulose 65.5%, lignin 20.5%, pentosan 11.6%, -cellulose 40.5% and extractives content of 5.15%, which made it comparable with the Acacia mangium wood sample. The alkali prehydrolysis of Moringa oleifera was carried out using 2% NaOH at 150 °C. The prehydrolysis liquor (PHL) was found to contain 50.9 mg/kg of calcium, 5140 mg/kg of potassium and 312 mg/kg of iron content. The prehydrolysis step was followed by Kraft pulping in order to obtain chemical grade pulp of kappa number 15-16 under optimized conditions. The Moringa oleifera pulp was bleached using the DEpD bleaching sequence to reach 85% brightness (ISO). The bleached pulp had an average fiber length of 1.21 mm, which was higher than that of Acacia mangium – 0.782 mm. The mechanical strength properties of the unbleached and bleached pulps, such as tear, tensile and burst indices, were also determined to show their suitability for pulp and paper production."

This article describes how crystalline or fibrous nanocellulose influences the mechanical properties of paper substrate. In this context, we used commercially available cellulose nanocrystals, mechanically prepared cellulose nanofibers dispersed in water or ethanol, and carboxy cellulose nanofibers. Selective reinforcement of the paper treated with the nanocellulose samples mentioned above was observed. The change in the fibre structure was assessed using scanning electron microscopy, roentgenography, and spectroscopy techniques. In addition, the effect of nanocellulose coating on physical properties was evaluated, specifically tensile index, elongation coefficient, Elmendorf tear resistance, Bendtsen surface roughness, Bendtsen air permeability, and bending strength. It can be concluded that the observed decrease in the strength properties of the paper after applying some NC compositions is due to the loss of potential disturbances in hydrogen bonds between the nanocellulose dispersed in ethanol and the paper substrate. On the other hand, significantly increased strength was observed in the case of paper reinforced with nanocellulose functionalized with carboxyl groups.

Influence of the thermochemical processing (the cook) conditions and of the milling on characteristic of the waste paper with polyurethan and polyaziridin was studied. The waste paper was reduced to the degree size of the particles 5...8 mm in mill of the dry grind and chemical processing under higher temperature (to 70 °C) by solution, contain sodium persulfate and hydroxide; duty of water 6. Duration of cook varied from 1 to 5 hours, expense of persulfate sodium varied from 2 to 12%, hydroxide sodium – from 0.5 to 3% from mass of the waste-papers. The secondary fiber was obtaining by breaking-up of the pulp in the hydropulper. The dependency of the length and factor of the form of the secondary fiber from conditions cook was absent. The slight width increasing of the fibers with the higher pH of cooking liquor was determined: from 26.5 мкм under pH 3–4 to 29 мкм under pH 8–9. The conjectural reason is swelling of the cell wall. The waste paper milling was executed in the «stream-barrier» machine. The strength properties of the paper correspond with the feature, inherent of the secondary pulp.

To improve the storage and transport of clinical specimens for the diagnosis of Neisseria meningitidis (Nm) infections in resource-limited settings, we have evaluated the performance of dried blood spot (DBS) and dried cerebrospinal fluid spot (DCS) assays. DBS and DCS were prepared on filter paper from liquid specimens previously tested for Nm in the United Kingdom. Nm was detected and genogrouped by real-time PCR performed on crude genomic DNA extracted from the DBS (n = 226) and DCS (n = 226) specimens. Targeted whole-genome sequencing was performed on a subset of specimens, DBS (n = 4) and DCS (n = 6). The overall agreement between the analysis of liquid and dried specimens was (94.2%; 95% CI 90.8–96.7) for blood and (96.4%; 95% CI 93.5–98.0) for cerebrospinal fluid. Relative to liquid specimens as the reference, the DBS and DCS assays had sensitivities of (89.1%; 95% CI 82.7–93.8) and (94.2%; 95% CI 88.9–97.5), respectively, and both assays had specificities above 98%. A genogroup was identified by dried specimen analysis for 81.9% of the confirmed meningococcal infections. Near full-length Nm genome sequences (>86%) were obtained for all ten specimens tested which allowed determination of the sequence type, clonal complex, presence of antimicrobial resistance and other meningococcal genotyping. Dried blood and CSF filter spot assays offer a practical alternative to liquid specimens for the molecular and genomic characterisation of invasive meningococcal diseases in low-resource settings.

This paper aimed to modify the ignitability of the bagasse paper by using talc powder, 1,3-di-aniline-2,2,2,4,4,4-hexachlorocyclodiphosph(V)azane, and nanocellulose crystal. The formation of cellulose nanocrystals (CNCs) was detected using transmission electron microscopy (TEM), X-ray diffraction (XRD). Thermal analysis as thermal gravimetric analysis (TGA) of the specimens recorded the improvement of the highest % of ash residue at 750 °C compared to the untreated one. The shape of the flame spread was studied. The ignition properties were studied for the untreated and treated specimens by limiting oxygen index (LOI) and flame chamber (UL/94), which recorded enhancing compared to the untreated specimen. This improvement was recorded either by measuring the mechanical properties (tensile strength, burst strength, elongation, and elasticity) of the specimens. The current article showed that the treated specimen was recorded the highest values compared to the untreated one in all physical, mechanical, and ignition properties, so these treatment paper sheets may be used as fire-retardant packaging materials.

The article to study the texture of paper, in the composition of which the cellulose pulp from the inner layer of mulberry branches bark is added, studies the paper’s absorbency and sorption properties. The absorbency of the paper was determined by the volume of water absorbed by the paper surface while wetting one side of the test sample. It was found that the addition of cellulose pulp from the inner layer of mulberry branch bark to the cotton paper pulp contributes to the strengthening of the structure which is confirmed by the values of mechanical strength and surface absorbency during one-side wetting with water. To study the physical structure of a paper sheet water vapor sorption was investigated in a high-vacuum sorption plant with mercury valves and quartz balances. On the basis of S-shaped sorption isotherms it is determined that the paper sample where the composition contains only cellulose pulp from the inner layer of the mulberry branches bark has the highest sorption properties which indicates the presence of disordered amorphous areas where the accessibility for water molecules is higher. It has been established that in order to obtain paper the structure of which ensured selective absorption of low-molecular fluid it is enough to add 10–20% of cellulose pulp from the inner layer of mulberry branches bark to the paper pulp; and further addition will result in misalignment of the paint contour during printing due to significant deformation of paper size.

Cellulose bromo-isobutyl ester was prepared using filter paper as raw material through esterification reaction with 2-Bromoisobutyryl bromide (BIBB) in N, N-Dimethyl-formamide (DMF). Cellulose esters with different degree of substitution were obtained. FTIR result indicated the successful introduction of bromo isobutyryl group in cellulose to obtain cellulose ester (Cell-Br). The surface of modified filter paper become rough and grooves could be observed by SEM. The thermal stability of the cellulose ester decreased in comparison with unmodified filter paper. Besides, the hydrophobicity of the filter paper was improved and the water contact angle increased from 73.4° to 116.5° with increasing degree of substitution. The water vapor barrier property was improved by 26 %. Furthermore, it was also found the modified filter paper possessed antibacterial activity against S. aureus bacteria. The modified filter paper obtained could be potentially used in food packaging fields and the results provide a simple method to prepare functional filter paper.

Lysergic acid diethylamide (LSD) is a hallucinogen, synthesized from ergot alkaloid, and controlled as a narcotic in Japan. Recently, LSD derivatives have appeared as designer drugs, all over the world. In previous study, we reported identification and analysis of four LSD derivatives in four paper sheet products. In this study, we detected three additional LSD derivatives from three paper sheet products, which were obtained from September 2019 to March 2020 in Japan. We extracted the compounds from paper sheet products with methanol for LC-MS, high-resolution MS and GC-MS analyses. The compounds were identified as 4-cyclopropionyl-N,N-diethyl-7-methyl-4,6,6a,7,8,9-hexahydroindolo[4,3-fg]quinoline-9-carboxamide (1cP-LSD), N-methyl-N-isopropyl-7-methyl-4,6,6a,7,8,9-hexahydroindolo-[4,3-fg]quinoline-9-carboxamide (MIPLA), 4-butyryl-N,N-diethyl-7-methyl-4,6,6a,7,8,9-hexahydroindolo[4,3-fg]quinoline-9-carboxamide (1B-LSD), by GC-MS, LC-MS, LC-Q-TOF-MS and NMR analyses. As well as other N1-acylated LSD derivatives, 1cP-LSD and 1B-LSD were easily deacylated to LSD during GC-MS analysis, we have to be careful to analyze these compounds.

The article gives the consideration to the properties of paper with the addition of pulp mass from the waste of the pharmaceutical industry, namely licorice root after removing extraction. Licorice roots were dried to air-dry state after extraction, cleaned of wastes and cut into fragments 10–30 mm long, then subjected to pulping with 2–4% NaOH solution at a hydro module 1 : 5, at a temperature of 95–98 °С for 60–90 minutes. After washing with hot water, they are bleached in an alkaline medium with a solution of hydrogen peroxide at a consumption of 3–4% of the mass of absolutely dry cellulose, hydro module 1: 5, temperature 70–95 °C for 60–90 minutes. After washing, grinding to a gristing degree of ~60°ShR, prepared castings weighting 80–90 g/m2 on a leaf-casting mashine. Physical, mechanical and optical properties of experimental castings are determined. Revealed that the addition of malt mass of the cotton contributes to the formation of dense orderly structures of the paper sheet, as short fibers of licorice filled the gaps between the long fibers of cotton pulp, thereby reducing the pore volume and reactive surface availability and receipt paper with the highest mechanical strength. Adding malt mass to cotton mass at a ratio of 10 : 2 is optimal, further replenishment contributes to an increase in sorption absorption, that is, to obtain paper with a porous structure, which is not desirable for high-quality reproduction.

Considering that optical properties play a very important role in the printing industry, this research focused on analysing the optical properties (opacity, whiteness, brightness and yellowness) of laboratory made papers from recycled wood pulp, with the addition of different straw contents, coated with titanium dioxide white ink. Titanium dioxide white ink was applied on laboratory papers to achieve optical characteristics as those of commercial papers recommended by ISO 12647. All the coated laboratory papers presented whiteness within the recommendations of the standard. Almost all the coated papers made with the addition of straw pulp achieved satisfactory optical properties, especially those containing 10% and 20% straw pulp. Coated laboratory papers containing 10% and 20% wheat pulp were comparable to commercial paper and reached a similar value of brightness, while their opacity and yellowness values were even better than those of commercial paper. In order to preserve the natural appearance of papers made with the addition of straw pulp, it is possible to conduct selective white printing as background for high-quality printing.

To prevent the abuse of new psychoactive substances (NPS), a total of 2372 substances and two plants are controlled as "Designated Substances" in Japan as of September 2019. Although the distribution of these substances has decreased for the past three years, newly-emerged NPS are still being found. In this study, we detected four lysergic acid diethylamide (LSD) derivatives as designer drugs from four paper sheet products, which were obtained from 2014 to 2017 in Japan. The compounds were identified as 4-Acetyl-N,N-diethyl-7-methyl-4,6,6a,7,8,9-hexahydroindolo[4,3-fg]quinoline-9-carboxamide (ALD-52), N,N,7-triethyl-4,6,6a,7,8,9-hexahydroindolo[4,3-fg]quinoline-9-carboxamide (ETH-LAD), 7-Allyl-N,N-diethyl-4,6,6a,7,8,9-hexahydroindolo[4,3-fg]quinoline-9-carboxamide (AL-LAD), N,N-diethyl-7-methyl-4-propionyl-4,6,6a,7,8,9-hexahydroindolo[4,3-fg]quinoline-9-carboxamide (1P-LSD), by GC-MS, LC-MS, LC-Q-TOF-MS and NMR analyses. Further, we studied the extraction methods of LSD derivatives from paper sheet, and the analytical conditions of GC-MS, LC-MS and LC-FL(fluorescence). Among LSD derivatives, 1P-LSD have been controlled as designated substances (Shitei Yakubutsu) under the Pharmaceutical and Medical Device Act in Japan since April 2016. For the legislation of the other derivatives identified in this study, the evaluation of their pharmacological properties are now in progress.

The article uses the example of artificially polluted soil to consider the effect of urea sorbent-a biological product "Unisorb-Bio" modified by waste paper on the biodegradation of oil with subsequent phyto-control of the soil by a test culture of pink-Swedish clover (Trifolium hybridum). It is shown that during 18 weeks of exposure "Unisorb-Bio" with immobilized on it the oil-oxidizing strains of Pseudomonas sp. and Bacillus subtilis, the oil content in the soil decreased by 10 times, which is on an order of magnitude higher to comparison with the control. High seeding qualities (germination energy, seed germination – 82%) are observed when using "Unisorb-Bio" modified waste paper from newsprint in conditions of 10% initial soil contamination, with a content of nitrophosca 0.05%. In the soil with" Unisorb-Bio "modified waste paper from the paper "Snegurochka" the indicators are lower by 17–20% than in the soil samples with biologics product modified by waste paper from newsprint, which is probably perhaps is bound up with more the greater destructibility of the latter under these conditions and an increase of mobile forms of nitrogen and phosphorus in the soil. The results of phytocontrol (germination energy, seed germination-52%) indicate a relatively good level of soil recovery with 15% initial contamination and almost independent of the type of biological product. The observed seeding quality and morphophysiological indicators give reason to conclude that the "Unisorb-Bio" biological product modified with waste paper is able to restore the soil even with a high level of contamination within one season.

WOS:000543297100009 For quality printing results that require detail, the smooth paper surface, absorbency, color and gloss are of great importance. Since the desired surface properties cannot be obtained even in well-polished paper, smooth paper surfaces can be obtained by sizing and coating processes. The aim of this study was to investigate the effect of different amounts of calcium carbonate, added into the surface coating formulation, on liquid absorbency and printability of paper. Paper coating formulations were created by adding 1%, 2.5%, 5% and 7.5% calcium carbonate to an equal amount of cationic starch binder. The obtained coating formulations were applied to the surface of standard pieces of paper with a lab coater. Water absorbency and drop contact angle of all papers (base paper and surface-treated paper) were measured by using the sessile droplet method and then their surface energies were calculated. After the gloss and color changes of the test papers were determined, test prints were applied on their surface with offset printing ink. The effect of surface treatments on the printability characteristics of the paper was examined in detail. It was emphasized that the amount of calcium carbonate used in cationic starch should be optimized with regard to the absorbency and printability of the paper.

Microfluidic paper-based analytical devices (µPADs) take the paper as a base material and integrate nanoscale microchannel on it for multiple detections. Its unique properties like low cost, portability, simple operation, and easy to save make it better than the traditional microfluidic chips. While designed originally for point-of-care medical diagnostics, µPADs have attracted the attention of many researchers in the fields of environmental monitoring, water quality, and food safety. The novelty of this paper is to present a detailed overview of µPADs for clinical applications. Firstly, a brief introduction to production methods, characteristics, and applications of these methods have been given. Secondly, the basic implementation, working principles, and corresponding performance of detection methods of clinical devices have been discussed, which enable the µPADs to detect biomarkers, human cells, bacteria, and viruses in a short time. Lastly, the factors that limit µPADs commercial applications, and their future research directions have also been briefly summarized.

Vapor phase polymerization has been used for the synthesis of polypyrrole-coated filter paper (PPy-FP) using a simple experimental setup. In addition, we have doped the polymer-coated filter papers...

In order to achieve high-quality colour prints by using an electrophotography (EP) printing machine, it is necessary to prepare the printing substrate. Additional treatment may be needed to achieve better substrate surface tension for optimally attaching the liquid EP ink to the paper. To ensure good adhesion of the ink to the printing substrate, a corona treatment may be used. During the corona treatment, the surface of the paper is modified, and the ability of paper to accept the ink is improved. In this study, we will determine the possibility of realizing CMY prints and of achieving an increased range of tone value in EP digital printing. Based on the results, the new possible values of reproduced CMY tones will be determined, so that higher print quality can be achieved. The results show that the best colour reproduction is achieved without the use of corona power (0 W). The additional activation of 450 W corona will result in the greatest colour variation of ∆EC = 0.60, ∆EM = 0.60 and ∆EY = 0.48.

Yenidogan, Semiha/0000-0002-1296-2392 WOS:000518368200010 Paper - ink interaction is extremely important in printing. Ideal printing outputs should be achieved with minimal ink consumption. It should not be supposed that visual printing quality will increase as the amount of ink increases. The effects of excessive ink consumption during the printing process on process sustainability, economy and environment should not be ignored. In this study, the effects of ink consumption during the printing process on printing quality parameters were mainly examined. Paper samples were printed with different amounts of ink, and the density and CIE L*a*b* values of the solid ink films were measured. The lightfastness test was applied to determine the resistance of the printed ink films to light, and the changes in their color were examined. Ideal ink amounts to reach ideal color L*a*b* values were determined and the effects of ink amount on the printing quality parameters were highlighted. Then, ink consumption was evaluated in terms of recycling, sustainability, environmental and economic effects, and recommendations were made to reduce the use of ink.

Starch is an inexpensive, easily accessible, and widespread natural polymer. Due to its properties and availability, this polysaccharide is an attractive precursor for sustainable products. Considering its exploitation in adhesives and coatings, the major drawback of starch is its high affinity towards water. This study aims to explain the influence of the silane-starch coating on the hydrophobic properties of paper. The analysis of the organosilicon modified starch properties showed an enhanced hydrophobic behavior, suggesting higher durability for the coatings. Molecules of silanes with short aliphatic carbon chains were easily embedded in the starch structure. Longer side chains of silanes were primarily localized on the surface of the starch structure. The best hydrophobic properties were obtained for the paper coated with the composition based on starch and methyltrimethoxysilane. This coating also improved the bursting resistance and compressive strength of the tested paper. A static contact angle higher than 115° was achieved. PDA analysis confirmed the examined material exhibited high barrier properties towards water. The results extend the knowledge of the interaction of silane compositions in the presence of starch.

Charantin is a mixture of β-sitosterol and stigmastadienol glucosides, which effectively lowers high blood glucose. Novel molecularly imprinted polymers coated magnetic nanoparticles (Fe3O4@MIPs) and filter paper (paper@MIPs) were synthesized by sol-gel polymerization to selectively extract charantin. β-sitosterol glucoside was selected as a template for imprinting a specific recognition owing to its larger molecular surface area than that of 5,25-stigmastadienol glucoside. Factorial designs were used to examine the effects of the types of porogenic solvents and cross-linkers on the extraction efficiency and imprinting factor before investigating other factors (for example, amounts of template and coated MIPs, and types of substrates for MIP immobilization). Compared to traditional liquid–liquid extraction, the optimal Fe3O4@MIP-based dispersive micro-solid phase extraction and paper@MIP extraction provided excellent extraction efficiency (87.5 ± 2.1% and 85.0 ± 2.9%, respectively) and selectivity. Charantin was well separated, and a new unidentified sterol glucoside was observed using the developed high-performance liquid chromatography with diode-array detection (Rs ≥ 2.0, n > 16,400). The developed methods were successfully utilized to extract and quantify charantin from M. charantia fruit powder and herbal products. Moreover, these methods are rapid (

Due to the massive use and abuse of pesticides, practices which have led to serious threats to human health, the research community must develop on-site and rapid detection technology of pesticide residues to ensure food safety. Here, a paper-based fluorescent sensor, integrated with molecularly imprinted polymer (MIP) targeting glyphosate, was prepared by a surface-imprinting strategy. The MIP was synthesized by a catalyst-free imprinting polymerization technique and exhibited highly selective recognition capability for glyphosate. The MIP-coated paper sensor not only remained selective, but also displayed a limit of detection of 0.29 µmol and a linear detection range from 0.5 to 10 µmol. Moreover, the detection time only took about 5 min, which is beneficial for rapid detection of glyphosate in food samples. The detection accuracy of such paper sensor was good, with a spiked recovery rate of 92–117% in real samples. The fluorescent MIP-coated paper sensor not only has good specificity, which is helpful to reduce the food matrix interference and shorten the sample pretreatment time, but it also has the merits of high stability, low-cost and ease of operation and carrying, displaying great potential for application in the on-site and rapid detection of glyphosate for food safety.

Resin acid amides of rosin, depending on the structure, can have both a hydrophobizing and hardening effect on paper pulps. It has been established that the developed products of rosin modification (adhesive rosin composition TMAS3N and polyamide resin ProChem DUO) containing amides of resin acids, when introduced into paper pulps made from fibrous suspensions of sulphate cellulose (unbleached and bleached) of coniferous and broad-leaved species and waste paper, different in the degree of grinding (25, 40 and 70 °ShR), contribute to the increase in the strength of interfiber bonds in paper in the z-direction. The effect of the TMAS-3N emulsion was compared with the traditionally used TM and AKD sizing emulsions. The introduction of the TMAS-3N emulsion into paper pulps (0.40 % of a. d. w.) provides the maximum increase in the strength of interfiber bonds in paper in the z-direction made from cellulose, equal to 16.7–88.6 %, and from waste paper – 19.4–75.4 %, which is 1.6–6.4 and 2.3–4.5 times more compared to TM emulsion, respectively. The achieved positive effect is due to the presence in the TMAS-3H emulsion of particles of the dispersed phase of hydroxyethylamides and aminoethyl ethers capable of forming hydrogen bonds with hydroxyl groups on the mating surfaces of cellulose fibers. Sizing paper stocks with AKD emulsion reduces the strength of interfiber bonds in paper in the z-direction over the entire range of paper content studied. Polyamide resin ProChem DUO, which is a polyaminoamide of rosin resin acids, at its content in paper stocks of 0.10 %, increases the strength of interfiber bonds in paper in the z-direction, made from cellulose and waste paper suspensions, by 50.0–92.3 and 44.4–63.5 %, respectively. The obtained results of increasing the strength of interfiber bonds in paper in the z-direction by resin acid amides of rosin are in full agreement with the mechanism of bridged bonds and the theory of hydrogen bonds.

In the modern world, the importance and volumes of packaging produced are constantly increasing. It is a powerful means of promoting goods on the market, but at the same time, the role of its quality increases. Currently, paper and paperboard packaging is not only a significant part of paper and paperboard market in general, but also a large part of the world’s packaging consumption. Currently, the world pays special attention to the use of secondary paper waste for the production of paper and cardboard and increase the volume of their processing. The article is devoted to the production of new types of multilayer paper and cardboard with the addition of chemical fiber and secondary waste, as well as high-quality paper and cardboard that can be used in the printing industry, in order to save valuable cotton cellulose in the country. However, the article shows in what proportions it is advisable to use secondary fibers in combination with cellulose in the production of multilayer composite paper and cardboard for the printing and paper industries.

This work describes a terbium luminescence-based protocol to selectively detect gallate-derived green tea polyphenols on a supramolecular gel immobilised paper platform for the first time. This user-friendly, inexpensive (� 0.0015) approach requires very low sample volumes for the analysis. The developed strategy enables simultaneous detection of gallate polyphenols in multiple tea samples with the potential for practical applications. © 2020 Wiley-VCH GmbH

Due to the important role of oil source in our life, the separation of water-in-oil emulsion is urgent and necessary. Membrane seperation technology has been an efficient and widely used method in separating oil-water separation. Herein, we report a versatile approach to fabricate surface carbonized membranes with self-standing property from biomass-derived precursor by synergistic charring of phytic acid, arginine and filter paper. The obtained membrane exhibited superhydrophobicity in oil, excellent fouling resistance, and self-supporting ability. The membrane can be cycle-used at least 12 times with high permeation flux (up to 1380 L·m−2·h−1) and separation efficiency (up to 99.4%).

In this study, biodegradable slow-release fertilizer (SRF) hydrogels were synthesized from hydroxyl propyl methyl cellulose (HPMC), polyvinyl alcohol (PVA), glycerol and urea (SRF1) and HPMC, PVA, glycerol, urea and blended paper (SRF2). The fertilizer hydrogels were characterized by SEM, XRD and FTIR. The swelling capacity of the hydrogels in both distilled and tap water as well as their water retention capacity in sandy soil were evaluated. The hydrogels had good swelling capacity with maximum swelling ratio of 17.2 g/g and 15.6 g/g for SRF1 and SRF2 in distilled, and 14.4 g/g and 15.2 g/g in tap water, respectively. The water retention capacity of the hydrogels in sandy soil exhibited higher water retention when compared with soil without the (SRFs). The soil with the hydrogels was found to have higher water retention than the soil without the hydrogels. The slow-release profile of the hydrogels was also evaluated. The result suggested that the prepared fertilizer hydrogels has a good controlled release capacity. The blended paper component in SRF2 was observed to aid effective release of urea, with about 87.01% release in soil at 44 days compared to the pure urea which was about 97% release within 4 days. The addition of blended paper as a second layer matrix was found to help improve the release properties of the fertilizer. The swelling kinetic of the hydrogel followed Schott’s second order model. The release kinetics of urea in water was best described by Kormeye Peppas, suggesting urea release to be by diffusion via the pores and channels of the SRF, which can be controlled by changing the swelling of the SRF. However, the release mechanism in soil is best described by first order kinetic model, suggesting that the release rate in soil is depended on concentration and probably on diffusion rate via the pores and channels of the SRF.

Utilization of paper wastes as renewable resource of lignocellulosic constituents has the opportunity to promote a cleaner environment and to prepare valuable materials. This paper describes our study on an isolation of low-fiber powder cellulose from two grades of wastes as feedstocks: waste newsprint paper and cardboard wrapper through recycling including a thermal defibration, an alkali treatment with a solution of NaOH with a concentration from 0.03 to 1.00 М, bleaching with a solution of Н2О2 with a concentration from 0.8 to 2.6 М followed with an acid hydrolysis of the pretreated species with a solution of HNO3 of 1.5 and 3.0 M. The impact of the pretreatment on sizes of fibers was evaluated with stereoscopic microscopy. The powder celluloses obtained as a result of the acid hydrolysis exhibited the structure of cellulose I revealed with a WAXS method and were of a high-grade purity, according to EDXA. Sorption capacities of the powder celluloses from the waste cardboard and newsprint towards a dye methylene blue were 6.67 and 8.75 mg g–1, respectively.

The poor barrier properties and hygroscopic nature of cellulosic paper impede the wide application of cellulosic paper as a packaging material. Herein, a polyvinyl alcohol (PVA)-based polymer coating was used to improve the barrier performance of paper through its good ability to form a film. Alkyl ketene dimer (AKD) was used to enhance the water resistance. The effect of the absorptive characteristics of the base paper on the barrier properties was explored, and it was shown that surface-sized base paper provides a better barrier performance than unsized base paper. Nanoclay (Cloisite Na+) was used in the coating formulation to further enhance the barrier performance. The results show that the coating of PVA/AKD/nanoclay dispersion noticeably improved the barrier performance of the paper. The water vapor transmission rate of the base paper was 533 g/m2·day, and it decreased sharply to 1.3 g/m2·day after the application of a double coating because of the complete coverage of the base paper by the PVA-based polymer coating. The coated paper had excellent water resistance owing to its high water contact angle of around 100°. The grease resistance and mechanical properties of the base paper also improved after coating. This work may provide inspiration for improving the barrier properties of packaging paper through the selection of a suitable base paper and coating formulation.

The article is devoted to solving an important scientific and technical task, improving the technology of production of tissue-paper. The study pays special attention to the problems related to the use of recovered paper, microscopic images of the surface of samples obtained from recovered paper sampling at various stages of the production of tissue-paper at the enterprise of Syktyvkar Tissue Group OJSC are presented. The main result of scientific research was a preliminary assessment of the study of the recovered paper stock preparation technology at the enterprise, for which the sampling from various stages of production were examined by a scanning electron microscope, which made it possible to visually assess the degree of cleaning of recovered paper from impurities from images of the microstructure of the surface of various scales. The chemical composition of the main additives was established by energy-dispersive X-ray spectral micro assay (EDX). Preliminary assessment of the nature of contamination, visual assessment of the microstructure of samples obtained from recovered paper stock from various stages of cleaning, allowed the engineers of the enterprise to evaluate the effectiveness of individual units of the stock preparation department for the production of tissue-paper. The obtained data will make it possible to specify the scientific and technical task and direct subsequent scientific work to improve the recovered paper stock preparation unit, which more requires perfection.

Herein, a facile strategy was proposed for preparing a high-strength and super-hydrophobic packaging paper with improved moisture and air barrier properties, which was derived from cellulosic pulps, micro-fibrillated cellulose (MFC), and nano-silica (n-SiO

To date, flexible pressure sensors built on silver nanowires (AgNWs) have attracted tremendous attention, owing to their versatile applications in wearable, human-interactive, health-monitoring devices. Cellulose and its derivatives, which show great promise in serving flexible pressure sensors as the desired substrate due to their natural abundance, biocompatibility, easy processibility, and low costs. Herein, we reported a rational strategy to design a silver nanowires-dual-cellulose conductive paper. Its morphology, chemical and crystal structures, thermal stability, mechanical performances, and electrical properties were carefully studied. The results suggested that good tensile properties (tensile strength ≤8.10 MPa), high electrical conductivity (≤ 1.74 × 10

The application of microfluidics for largescale rapid analytics holds great promise in the pharmaceutical diagnostics and analytical chemistry. Here we report a paper based microfluidic substrate designed by the impregnation of Silver nanoparticles. This study demonstrates the achievement of a thousand-fold increase in the successful detection level up to 10 ppb (90.8 nM) by employing Surface Enhanced Raman Spectroscopy (SERS) for the detection of Catechol. The presented sensor exhibits the following main features: (i) high specificity of enzyme (Hemocyanin)-based sensing, (ii) effective SERS sensitivity, (iii) easiness and cost-effectiveness of a paper-based platform. We rationalize these findings using the ab initio DFT simulations using Gaussian 09 whose theoretical calculations reflect the observed experimental Raman peaks.

This study reports on eco-friendly graft polymerization approach for the modification of a cellulosic material via combination between enzymatic catalysis and reversible addition-fragmentation chain transfer polymerization (RAFT). Polyacrylamide (PAM) was polymerized on a cellulosic filter paper via horseradish peroxidase (HRP)-initiated RAFT polymerization. The results of grafting ratio, conversion, and pseudo-first-order kinetics were proved that the PAM graft polymerization on the filter paper followed RAFT rules. The results of Attenuated total reflection (ATR-FTIR), elemental analysis, and X-ray photoelectron spectroscopy (XPS) confirmed the presence of PAM in PAM-grafted filter paper. The results of water contact angle and Thermogravimetric analysis (TG) evidenced the change in the wetting properties and thermal performance, respectively of the treated filter paper. This work provides a new environmentally approach to graft polymerization on cellulosic materials.

Novel high-performance biosensing devices, based on a microporous cellulose matrix, have been of great interest due to their high sensitivity, low cost, and simple operation. Herein, we report on the design and testing of portable paper-based immunostrips (IMS) for in-field blood typing in emergencies requiring blood transfusion. Cellulose fibrils of a paper membrane were functionalized with antibodies via supramolecular interactions. The formation of hydrogen bonds between IgM pentamer and cellulose fibers was corroborated using quantum mechanical calculations with a model cellulose chain and a representative amino acid sequence. In the proposed immunostrips, paper with a pore size of 3 µm dia. was used to enable functionalization of its channels with antibody molecules while blocking the red blood cells (RBC) from channel entering. Under the optimized test conditions, all blood types of AB0 and Rh system could be determined by naked eye examination, requiring only a small blood sample (3.5 µL). The durability of IgM immunostrips against storing has been tested. A new method of statistical evaluation of digitized blood agglutination images, compatible with a clinical five-level system, has been proposed. Critical parameters of the agglutination process have been established to enable future development of automatic blood typing with machine vision and digital data processing.