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According to historical documents, the identity of a nation or ethnic group in each period is determined. Maintain these documents according to their structural nature that was so vulnerable to deterioration of the utmost importance. What factors should be considered Identify damaging agents and attempts to reduce it. Biological degradation is the main cause of damage to paper documents. To solve this problem, various methods were used. The most common method is using chemical antiseptic such as thymol, para chloro benzene dioxide, ethylene oxide etc. But what this study will examine the effects of abuse on the structure of these materials is cellulose paper such as ethylene oxide, indicating improper methods to remove the erosion and provide a convenient method, including freezing in order to reduce these damages. In this paper, 673 paper samples were studied, of the type of documents, which were identified first by the chemical laboratory method and then based on the information obtained from the results of tests with laboratory devices (FTIR, pH-meter). as well as by other methods. Aging, acidity and the effect of disinfectants on the structure of documents and fibers have been analyzed. In this research, which was tested on 673 paper samples, the type of dough was first identified by chemical laboratory method and then with the information obtained from the test results by laboratory devices (pH, FTIR meter) as well as methods. Aging, acidity and the effect of disinfectants on the structure of documents and fibers have been analyzed. [ABSTRACT FROM AUTHOR]

The chemical structure of organic matter (OM) pools in the 2–1-mm water-stable macroaggregates isolated from air-dry aggregates of the same size in arable horizons of noneroded, eroded, and depositional agrochernozems was studied with solid-state 13C-NMR spectroscopy. The changes in their chemical structure in the denudation–accumulative landscape are assessed. The overwhelming majority of water-stable macroaggregates in the erosional zone are newly formed due to dynamic replacement of OM in situ, which is clearly demonstrated by the integral chemical structure indicators in all OM pools in macroaggregates. Analytical data suggest the prevalent transport of newly formed macroaggregates. The destruction of macroaggregates during the transport phase is accompanied by the release of previously physically protected aggregated OM, which undergoes partial mineralization. Note that its most labile (hydrolyzable) part is predominately mineralized, whereas its stable part remains weakly changed or intact. Mineral-associated OM (clay and residue) weakly changes or does not change at all, retaining relative freshness, which indirectly suggests the prevalent migration of newly formed macroaggregates from the erosional zone. A greater degree of freshness of LFfr (free OM) in macroaggregates of depositional agrochernozem results from the abundance of fresh crop residues of the depositional zone together with the residues transported from the erosional zone. [ABSTRACT FROM AUTHOR]

Splash erosion, the first step in water erosion process, occurs because of raindrops collusion with soil aggregates and pushing soil particulates into the air. The objective of this study was to test the usability of water sensitive paper (WSPs) in assessment of splash erosion. Soil losses from three texturally different soils by splash erosion were determined under artificial rainfall conditions as a function of splash distance and direction. The results indicated that the amount of soil removed by splash erosion was significantly affected by soil texture, splash direction and distance, and was the highest in clay soil and the lowest in sandy loamy soil. About half of the splashed soil material moved down slope, 34% in the lateral direction, and 17% moved upslope. A significant positive correlation between the WSPs-D10 diameter and the WSPs-surface coverage rate was obtained, which indicates that the higher the D10 diameter, the higher the surface coverage rate. The results obtained in this study reveal that the WSPs cards could successfully be used and its parameters (WSPs-D10 diameter and WSPs-surface coverage rate) might be considered as a new approach in assessing and evaluating splash erosion. [ABSTRACT FROM AUTHOR]

Abstract: Coating blades are used in the paper industry to meter off the excess coating applied to the paper. They are essential in attaining high-quality coating films with minimum operating cost. During the coating process, the blades are worn down at the tip and are replaced when the coating quality degrades. The objectives of this study are to predict the wear rate of the blades and examine the hypothesis that the blades wear into a quasi-steady-state wear profile, despite both low- and high-angle particle impact. Experimental data and results from finite element simulations are presented for a series of blade materials and suspensions. The approach taken differs considerably from earlier studies, in that it treats blade wear as erosion from the action of the impacting slurry particles rather than abrasion, thus explaining the enhanced wear around the heel. The current approach relies on computer experiments to solve the equations for the liquid flow field, the individual particle motion, the substrate deformation and the eroded volume of the blade, rather than employing empirical relations between wear rates and average fluid velocity. The shear thinning behavior of the coating suspension was properly taken into account. To validate the calculations, blade samples from both a pilot and an off-machine coater were collected at a variety of time intervals. The blade samples aided not only in the establishment of the wear rates and the identification of the wear patterns, but also in the confirmation of the steady-state wear hypothesis that is correctly predicted by the simulations. [Copyright &y& Elsevier]

Using Landsat data, the authors have found the variation of width, shifting of bank lines, sinuosity and areas subjected to scouring and silt deposition in river Ganga for a stretch 175 km long from Bhagalpur to Farakka during the period 1973-2019. Information furnished by the authors will be beneficial not only for future planning of hydraulic structures like bridges, barrages, etc., but also for river training, navigation and other river improvement works of river Ganga. Flow in Ganga River is normal upstream of Kaliachak/Rajmahal about 30 km upstream of Farakka and the river continues to flow in its own normal regime as in pre-barrage state. In pre-historic days, river Hoogly was the main Ganga flowing by the side of Kolkata. [Extracted from the article]

When buildings are exposed to erosion from the natural environment, erosion behaviors such as surface damage and structural instability occur, which greatly affect the aesthetic value and service life of the buildings. The study of erosion behaviors and the establishment of a suitable erosion model are constructive references for the protection and restoration of buildings. In order to establish a suitable erosion model for architectural red sandstone, two types of red sandstone specimens were selected in this paper to carry out dry and wet cycle tests. Combining the theoretical analysis and the actual erosion situation, a unidirectional corrosion model is proposed to describe the erosion of buildings by the natural environment. In this model, it is assumed that only the outer surface of the building is in contact with external erosion factors for a long period of time, so this situation can be considered a unidirectional erosion process. The paper uses XRD, SEM, and ultrasonic methods to record changes in the properties of the red sandstone samples. Finally, the rationality of the unidirectional erosion model was verified numerically. The test results show that the red sandstone specimens subjected to erosion by the natural environment will be accompanied by the development of defects, such as cracks, fissures, and holes, as well as the generation of fresh material. The demarcation point of different erosion stages exists in both the in-service red sandstone specimens and the fresh red sandstone specimens, which is consistent with the results of the unidirectional erosion model. In this paper, a calculation model for the demarcation point of different erosion stages is established, and the model estimation shows that the demarcation point of different erosion stages of the in-service red sandstone sample is 1.1528 cm from the erosion surface, and the demarcation point of different erosion stages of the fresh red sandstone sample is 1.67 cm. [ABSTRACT FROM AUTHOR]

Purpose: Over the seventy years, various soil erosion modeling methods were developed in the world with different input requirements and complexity. Some of these soil erosion models have been applied in Sri Lanka covering several regions of the country at different scenarios over the past twenty years. Thus, the prime objective of this study is to compare commonly practiced GIS/RS based soil erosion assessment models and derivation techniques of model parameters used in Sri Lanka. Research Method: Scholarly research articles, conference proceeding papers, and previously published literature on GIS/RS based soil erosion models over the past twenty years were critically reviewed, examined, and compared to find various methodologies in the derivation of soil erosion model parameters, analysis methods, and applications with special reference to Sri Lanka. Findings: The results revealed that, in each case, the empirical soil erosion models have been applied to predict soil erosion rates in terms of rill and sheet erosion excluding gully erosion. Furthermore, soil loss at the catchment or entire country scale has been assessed in each case by using different derivation methods. The assessed soil erosion model parameters are R factor (rainfall erosivity), K factor (soil erodibility), LS factor (slope gradient), C factor (crop management factor), and P factor (support practice factor). Originality/Value: Different derivation methods of soil erosion model parameters (R, K, LS, C, and P) were critically evaluated in order to find the most appropriate methods that can be applied in Sri Lanka in future research studies. [ABSTRACT FROM AUTHOR]