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This article presents the information on the valorization of waste generated during the production of tissue paper. The possibility of bioconversion of the polysaccharide part of paper sludge into simple sugars has been evaluated. The options for processing the paper sludge before enzymic hydrolysis to achieve the maximum yield of monosaccharides have been considered. Pretreatment with acids has been found to be a key step before the biocatalytic cleavage of waste polysaccharides. An additional yield of enzymic hydrolysis products after pretreatment with acids has been obtained by pre-extraction of the paper sludge with spirit or acetone. It has been established that the most intense enzymic hydrolysis of readily available fractions of the paper sludge takes place in the first 10–12 hours. Further, the process slows down, probably due to the action of the remaining components of the fillers, as well as an increase in the proportion of the difficult-to-hydrolyze polysaccharide part. In all cases, the proportion of absolutely dry non-hydrolyzed residue has been about 43±2 % of the dry matter of the paper sludge. The main products of enzymic hydrolysis have been glucose and xylose. The resulting sugars have been used for mixotrophic cultivation of the Tetradesmus obliquus and Chlorella vulgaris algae. Yeast strains have been selected for the conversion of monosaccharides from the paper sludge. In a series of experiments on non-sterile yeast cultivation, the Candida utilis PAL D and Debaryomyces hansenii SWING R cultures have turned out to be the most productive (within 2.10±0.14 g of air-dry yeast weight/dm3 per 24 hours). The degree of conversion of hydrolysate sugars has been 70±2 %. Most of the remaining sugars (about 80 %) have been represented by xylose. Complete utilization of the sugars has taken place on the 2nd day when having added an extra nitrogen source to the medium. On the other hand, the spent nutrient medium after yeast separation has been suitable for mixotrophic cultivation of microalgae. It has been revealed that the economic costs of pre-treatment of the paper sludge with nitric acid can be leveled by using the resulting salts as a nitrogen source for cultivating yeast. In doing so, the yield of yeast biomass increases by almost 2 times.

The article considers insufficiently studied problem of preservation underwater archaeology paper objects. The author shares good practical experience conservation and restoration of unique artefacts found by archaeologists on the merchant ship « Die Engiel Raphael » (Archangel Raphael) sanked almost 300 years ago. The main attention is focused on an integrated approach and consolidation of the efforts of restorers, underwater archaeologists and divers, researchers to determine the conservation method. In constant close collaboration with specialists from the workshop for graphics, books and documents conservation of the Grabar Art Conservation Center and of the Center for Underwater Research of the Russian Geographical Society has been developed a method for the conservation of four underwater archaeology paper objects. The article presents the results of research and restoration. Various techniques for drying, separating of cemented book-pages and ultrasonic cleaning for removing sandy-clay pieces, deeply embedded from the paper structure, are described. In developing main guidelines emphasized of conservation work for underwater artifacts, highlights the need for a special approach to each object and creation an individual program for restoration activities, taking into account its specifics. In forming the general basic principles of conservation of underwater artefacts, the necessity of a special approach to each object and drawing up an individual program of restoration measures, taking into account its specifics, is noted.

The process of recycled pulp refining is usually associated with a significant change in the morphological characteristics of the secondary fiber and the formation of additional amounts of fines. It is well known that fines have a great impact on the pulp properties, the papermaking process and the quality of the resulting paper. At the same time, the effect of fines both on the paper properties and on the papermaking process depends on the morphological characteristics of the fines. The aim of the study was to evaluate the changes in the morphological characteristics of the fines during gentle low-consistency refining of the recycled pulp. The recycled pulp was obtained from commercial wet-strength tissue paper, consisting of 100 % bleached softwood kraft pulp (BSKP) made from pine (Pinus sylvestris L.). The repulping of wet-strength paper was performed at 60 °C in three ways, namely, repulping with sodium hydroxide (indicated as RP (NaOH)), repulping with sodium hydroxide and sodium persulfate (RP (NaOH + Na2S2O8)), and finally repulping with sodium hydroxide and potassium monopersulfate (RP (NaOH + KHSO5)). Using an optical fiber analyzer, L&W Fiber Tester, it was found that accelerated persulfate and monopersulfate repulping of the wet-strength paper led to an increase in fines content after pulp refining by 0.20…0.28 % on length and by 0.9…1.5 % on number of particles. In addition, some fines were not detected due to the limited resolution of the measuring device. The morphological characteristics of the recycled pulps showed that the studied fines were relatively straight particles (Sl = 93.5...94.0 %) with low length polydispersity ((Ll/Ln) = 1.08...1.09). Fines had a mean slenderness ratio (L/W)l and (L/W)w of about 7, which in some length classes reached 8...9. Taking into account the experimental data on fines length (Ll = 132…134 µm) and fiber width (Wl = 29.7…30.0 µm), as well as SEM images of recycled paper, we can conclude that these particles can form fines-assisted bridges between several close deposited fibers in the fiber network, thus strengthening the paper web. For citation: Penkin A.A., Kazakov Y.V. Changes in the Morphological Characteristics of Secondary Fiber Obtained from Wet-Strength Paper During Gentle Refining of the Recycled Pulp. Part 2. Fines Characteristics. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 169–179. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-169-179

The article introduces attraction marketing methods employed by Russian monthly popular science magazine Diletant. The authors compared the printed version and the website. The paper magazine attracts the reader mainly by the topic name printed on its cover as a unique creolized text. The further semantics of the front media text includes various aspects of the main topic. Color highlights both topical issue and regular features. The comparative analysis with the online version revealed some significant differences. The website has a muted color scheme and minimal animation; it contains neither video nor audio materials. Like in the printed version, the function of attraction belongs mainly to illustrations and subtitles. Online Diletant is interactive in navigation, tests, and surveys, which are, however, the only form of interactivity: the site does not provide comments, forums, “likes”, etc. Such limited use of attention-seeking tools makes the digital version of Diletant uncompetitive and inferior to its paper issue.

Most paper mills in the Russian Federation consume around 40 % more electrical power than they actually require. The reasons are a low level of technical, scientific, and proficient assistance. Moreover, the produced goods have non-competitive consumption characteristics. The urgent current measures in this matter contain constructional and technological optimization, including drying temperature modes. The drying section of a paper machine is the most energy-consuming, while it significantly affects the mechanical strength and supplementary properties of the resulting paper goods with their structural and dimensional characteristics. Drying the paper web takes 72–77 % of the total energy of the paper machine. Therefore, the purpose of this study is to analyze the influence of the temperatures of the drying process on the strength and structural-dimensional properties of the paper, with the perspective for further application of the results in the practice of industrial companies and additional scientific investigation. The presented results show the influence of pulp type, beating degree, mass of 1 m2, and drying temperature on the strength and structural-dimensional properties of laboratory samples. Within the investigational process, laboratory samples from sulphate-bleached softwood and hardwood pulp were created and tested. The weights of the samples varied from 60 to 120 g/m2, and the beating degrees ranged from 20 to 50 °SR. The drying temperature extended from 80 to 140 °C. The analysis of the acquired paper samples revealed that the drying temperatures had a considerable impact on the strength, structure, and dimensional qualities of the material. Namely, while sulfate-bleached softwood and hardwood pulp types were used as a raw material, increasing the drying temperature from 80 to 140 °C had the greatest effect on the structural-dimensional properties of the paper made from a pulp with a higher beating degree and the greatest effect on the strength properties of the paper made from a pulp with a lower beating degree. For citation: Prokhorov D.A., Dubovy V.K. Influence of Drying Temperature on Paper Properties Made of Sulfate-Bleached Softwood and Hardwood Pulps. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 3, pp. 173–184. (In Russ.). https://doi.org/10.37482/0536-1036-2023-3-173-184

In 1921 Mellin published a Comptes Rendu paper computing the principal solution of a polynomial using generalized hypergeometric functions of its coefficients. He used an integral transform nowadays bearing his name. Slightly over three pages, the paper is written in French in a terse style befitting the language. This article makes Mellin’s landmark result accessible to people who are not experts in hypergeometric functions and complex analysis by deriving detailed proofs that were omitted in Mellin’s paper.

Printing companies play a central role in the exercise of general elections. However, there have been some issues in the number of printed ballot papers not relevant to the quantity requested by the General Election Commission, and this situation is considered election crime. Article 529 of Election Law implies that the printing company concerned may be subject to imprisonment or fines, but the legislation declares that a jail sentence cannot be imposed on the company. Departing from this issue, this research aims to analyze and find the ratio legis of criminalization of a printing company responsible for producing ballot papers for general elections. With a normative method and statutory, conceptual, and historical approaches, the research discovers that a lack of inaccuracy of drafters in the making of an academic draft on elections, where the drafters ruled out the notions of experts of criminal law and Supreme Court as delivered in a legislation-making session, seemingly gives Article 529 impunity. That is, the criminal sanction that should be imposed on a printing company following ballot paper manufacturing issues governed in Article 529 of Election Law does not guarantee any legal certainty and democratic general elections with integrity. The sanctions imposed on the company concerned should only be restricted to administrative measures like fines and no incarceration should be involved.