scholarly journals Oxidative degradation of non-recycled and recycled paper

Cellulose ◽  
2020 ◽  
Vol 27 (15) ◽  
pp. 8977-8987
Author(s):  
Floriana Coppola ◽  
Alberto Modelli
Keyword(s):  
Oxidative Degradation ◽  
Carbonyl Groups ◽  
Carbonyl Content ◽  
Potassium Periodate ◽  
Recycled Paper ◽  
Pure Cellulose ◽  
Different Types ◽  
The Difference ◽  
Reported Data ◽  
Linear Correlations

Abstract The degradation of paper-based materials involves several and complex mechanisms, such as hydrolysis and oxidation. The behaviour of different types of pulps can be very variable. In this study, the difference upon oxidation of contemporary non-recycled and recycled papers, which now constitute a considerable fibre source, is investigated. A 0.015 M potassium periodate solution is used to oxidise five types of paper, two non-recycled and three recycled, for 0.5, 1, 2 and 4 h. The effects of such oxidation treatments are evaluated in terms of carbonyl content and degree of polymerisation (DP). A modified procedure of the Szabolcs’s method and viscometry are used to measure the carbonyl content and DP, respectively. The carbonyl groups are found to increase more rapidly in the recycled papers than in the non-recycled ones. On the contrary, oxidation causes a larger decrease of the DP values in the non-recycled papers, the paper made of pure cellulose being the most sensitive in terms of depolymerisation. The DP values measured for pure cellulose paper are in line with previously reported data. Moreover, in accordance with the Ekenstam equation, the plots of the reciprocal of DP as a function of oxidation time show good linear correlations for all types of paper investigated. Pseudo rate constants are thus calculated from the slopes of these plots, those of the non-recycled papers being found to be higher than those of the recycled papers. Graphic abstract

scholarly journals Surface Chemical Heterogeneity of Low Rank Coal Characterized by Micro-FTIR and Its Correlation with Hydrophobicity

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 239
Author(s):  
Wei Wang ◽  
Long Liang ◽  
Yaoli Peng ◽  
Maria Holuszko
Keyword(s):  
Surface Chemistry ◽  
Functional Group ◽  
Group Composition ◽  
Contact Angles ◽  
Low Rank ◽  
Surface Chemical ◽  
Carbonyl Groups ◽  
Low Rank Coal ◽  
Different Types ◽  
Aliphatic Carbon

Micro-Fourier transform infrared (micro-FTIR) spectroscopy was used to correlate the surface chemistry of low rank coal with hydrophobicity. Six square areas without mineral impurities on low rank coal surfaces were selected as testing areas. A specially-designed methodology was applied to conduct micro-FTIR measurements and contact angle tests on the same testing area. A series of semi-quantitative functional group ratios derived from micro-FTIR spectra were correlated with contact angles, and the determination coefficients of linear regression were calculated and compared in order to identify the structure of the functional group ratios. Finally, two semi-quantitative ratios composed of aliphatic carbon hydrogen, aromatic carbon hydrogen and two different types of carbonyl groups were proposed as indicators of low rank coal hydrophobicity. This work provided a rapid way to predict low rank coal hydrophobicity through its functional group composition and helped us understand the hydrophobicity heterogeneity of low rank coal from the perspective of its surface chemistry.

scholarly journals Analysis of the Pyrolytic Behaviour of Birch, Maple, and Rowan Leaves

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2091
Author(s):  
Valentina Zubkova ◽  
Andrzej Strojwas ◽  
Marcin Bielecki
Keyword(s):  
Combustion Products ◽  
Carbonyl Groups ◽  
Chemical Parameters ◽  
Chemical Reagents ◽  
Urban Greenery ◽  
Volatile Products ◽  
Different Types ◽  
Ft Ir ◽  
Xrd Techniques ◽  
Lower Contribution

A research study was conducted on the thermal behaviour of leaves of urban greenery (birch, maple, and rowan) and the products of their pyrolysis and extraction as assisted by microwaves. The obtained products of pyrolysis and extraction were investigated with the use of FT-IR and UV spectroscopies and XRD techniques. A contractive analysis of samples of chars, condensates, after-extraction residue, and extracts showed that the changes in structural-chemical parameters of leaves of different types of trees during pyrolysis and extraction take place in distinct ways. About 22% of material was removed from birch leaves during extraction, and more than 17% of material was extracted from maple and rowan leaves. It was determined that, during pyrolysis of after-extraction residue of leaves, many fewer PAH compounds with carbonyl groups along with alcohols and phenols are emitted than during pyrolysis of non-extracted leaves. Taking into account that pyrolysis is the first stage of combustion, a decrease in the amount of dangerous compounds in the volatile products of pyrolysis leads to a lower contribution of such compounds in combustion products. This indicates that leaves of urban greenery can be subjected to combustion after extraction, and the obtained extracts can be used as a source of phytochemicals and chemical reagents.

scholarly journals Investigation of Color Reproduction on Linen Fabrics when Printing with Mimaki TX400-1800D Inkjet with Pigment TP250 Dyes

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 354
Author(s):  
Tim Tofan ◽  
Rimantas Stonkus ◽  
Raimondas Jasevičius
Keyword(s):  
Mechanical Properties ◽  
Color Reproduction ◽  
Related Effect ◽  
Color Characteristics ◽  
Fabric Density ◽  
Different Types ◽  
The Difference ◽  
Printing Parameters ◽  
Linen Fabric

The aim of this research is to investigate related effect of dyeability to linen textiles related to different printing parameters. The study investigated the change in color characteristics when printing on linen fabrics with an inkjet MIMAKI Tx400-1800D printer with pigmented TP 250 inks. The dependence of color reproduction on linen fabrics on the number of print head passes, number of ink layers to be coated, linen fabric density, and different types of linen fabric was investigated. All this affects the quality of print and its mechanical properties. The change in color characteristics on different types of linen fabrics was determined experimentally. We determine at which print settings the most accurate color reproduction can be achieved on different linen fabrics. The difference between the highest and the lowest possible number of head passages was investigated. The possibilities of reproducing different linen fabric colors were determined.

scholarly journals Evaluation of Wear Behaviour in Metallic Binders Employed in Diamond Tools for Cutting Stone

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3988
Author(s):  
Fátima Ternero ◽  
Pedro M. Amaral ◽  
Jorge Cruz Fernandes ◽  
Luís Guerra Rosa
Keyword(s):  
Wear Behavior ◽  
Wear Behaviour ◽  
Empirical Expression ◽  
Testing Conditions ◽  
Diamond Tools ◽  
Test Methodology ◽  
Different Types ◽  
Stone Material ◽  
The Difference ◽  
Wear Tests

A type of disc-on-plate test methodology was used to determine the wear behavior of metallic binders employed in the manufacturing of diamond impregnated tools. The disc consists of a special circular wheel that allows the binder materials alone (i.e., without diamond, but sintered under conditions identical to those of the complete tool) to be tested against a plate of stone material under pre-determined testing conditions. The testing conditions are intended to be equivalent to those used in the industrial processes. Using plates of five types of granite and one type of marble, this work comprises wear tests of 15 different types of metallic binders and two sintering modes conducted under, at least, three different values of contact-force. The analysis of the results demonstrated that the wear of the binders can be related to their mechanical properties through an empirical expression. The larger the difference between the characteristics of the tribological pair (binder versus stone), the higher is the correlation between the experimental wear data and the values given by the empirical expression. The relationships presented in this work allow predicting the wear behavior of the binder, and therefore may help in the design process of diamond tools. There was a clear difference between the wear behavior of metallic binders when they were employed against the two main classes of stone under analysis (marble and granite).

Parent-Reported Medication Use in a Head Start Population

2008 ◽  
Vol 24 (5) ◽  
pp. 319-325
Author(s):  
Tara M. Brinkman ◽  
John S. Carlson
Keyword(s):  
Head Start ◽  
Low Income ◽  
Medication Use ◽  
School Nurses ◽  
Psychotropic Medications ◽  
Hispanic Children ◽  
Raising Awareness ◽  
Head Start Children ◽  
Different Types ◽  
Reported Data

This study investigates the prevalence of medication use within a Head Start population. Parent-reported data ( N = 1,397) from initial enrollment information indicated 6.8% of children were taking 34 different types of medication. More than two thirds (69%) of those on medication were prescribed more than one medication, and more than one third (37%) were taking three or more medications. The majority of children were reported to be taking medications that were asthma (88%) or allergy (17%) related. Psychotropic medications accounted for 4% of the medications, indicating a prevalence of less than 0.3%. African American and Hispanic children were overrepresented in those taking medicines. School nurses can work with parents and caregivers of Head Start children by raising awareness of (1) the benefits and side effects of medications commonly taken within this population, (2) the significant role that asthma medications play in low-income areas, and (3) the issues and challenges associated with polypharmacy practices.

scholarly journals Bright Side of Fusarium oxysporum: Secondary Metabolites Bioactivities and Industrial Relevance in Biotechnology and Nanotechnology

2021 ◽  
Vol 7 (11) ◽  
pp. 943
Author(s):  
Sabrin R. M. Ibrahim ◽  
Alaa Sirwi ◽  
Basma G. Eid ◽  
Shaimaa G. A. Mohamed ◽  
Gamal A. Mohamed
Keyword(s):  
Fusarium Oxysporum ◽  
Cyclic Peptides ◽  
Pathogenic Fungi ◽  
New Drugs ◽  
Biotechnological Applications ◽  
The World ◽  
Different Types ◽  
Bright Side ◽  
Reported Data ◽  
Industrial Relevance

Fungi have been assured to be one of the wealthiest pools of bio-metabolites with remarkable potential for discovering new drugs. The pathogenic fungi, Fusarium oxysporum affects many valuable trees and crops all over the world, producing wilt. This fungus is a source of different enzymes that have variable industrial and biotechnological applications. Additionally, it is widely employed for the synthesis of different types of metal nanoparticles with various biotechnological, pharmaceutical, industrial, and medicinal applications. Moreover, it possesses a mysterious capacity to produce a wide array of metabolites with a broad spectrum of bioactivities such as alkaloids, jasmonates, anthranilates, cyclic peptides, cyclic depsipeptides, xanthones, quinones, and terpenoids. Therefore, this review will cover the previously reported data on F. oxysporum, especially its metabolites and their bioactivities, as well as industrial relevance in biotechnology and nanotechnology in the period from 1967 to 2021. In this work, 180 metabolites have been listed and 203 references have been cited.

scholarly journals LOGICAL REASONING ANALYSIS BASED ON HIPPOCRATES PERSONALITY TYPES

Aksioma ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 57-73
Author(s):  
Nurdin Nurdin ◽  
Ita Sarmita Samad ◽  
Sardia Sardia
Keyword(s):  
Problem Solving ◽  
Mathematical Problem ◽  
Logical Reasoning ◽  
Personality Types ◽  
The Body ◽  
Mathematical Problem Solving ◽  
Different Types ◽  
Ways Of Thinking ◽  
The Difference ◽  
Descriptive Qualitative

Abstract: The theory distinguishes human based on four different personality types such as: sanguine, choleric, melancholic, and phlegmatic. Different types of personality caused by differences in the dominant fluid in the body. These differences will result in terms of behavior, ways of thinking and to get along. The type of this research that is descriptive qualitative which it is describing the logical reasoning based on Hippocrates personality types. The logical reasoning is analyzed through the four types of personality in relation to mathematical problem solving. The Analysis is done based on the logical reasoning indicator/ subindicator and the steps of problem solving stated by Polya. The result shows that there is a reasoning difference on each type of personalities. The difference can be terms of the strenght or the weakness. Sanguine is quicker in understanding problems and communicating results, choleric is more accelerated in work, melancholic is more perfect at work, and  phlegmatic is superior in terms of accuracy. Keywords: Logical reasoning, Hippocrates, sanguine, choleric, melancholic, phlegmatic

scholarly journals Philosophies of interreligious dialogue: Practice in search of theory

2011 ◽  
Vol 1 (1) ◽  
pp. 16-24 ◽  
Author(s):  
Oddbjørn Leirvik
Keyword(s):  
Civil Society ◽  
Religious Education ◽  
Emmanuel Levinas ◽  
Interreligious Dialogue ◽  
Interfaith Dialogue ◽  
Faith Communities ◽  
Different Types ◽  
The Difference ◽  
Mutual Change

In this article, I discuss how insights from Martin Buber’s and Emmanuel Levinas’ philosophies of dialogue have enlightened my own experience of inter-faith dialogue in Norway. Central perspectives here are Buber’s notion of ’the realm of the between’ and Levinas’ emphasis on asymmetry and vulnerability. Some other philosophers’ reasonings about dialogue are also considered, from the overall perspective of ’practice in search of theory’. In connection with a distinction be-tween different types of dialogue (’spiritual’ and ’necessary’), the difference between government initiated ’dialogue’ and initiatives originating from the faith communities (i.e., civil society) are discussed. The last part of the article analyses the notion of ’(mutual) change’ which is often brought forward when discussing the aims of interfaith dialogue. In this connection, religious education in school is also considered as a possible arena for dialogue—and ’change’.

scholarly journals Non-Negligible Effects of UV Irradiation on Transformation and Environmental Risks of Microplastics in the Water Environment

2021 ◽  
Vol 12 (1) ◽  
pp. 1-12
Author(s):  
Fangyuan Cheng ◽  
Tingting Zhang ◽  
Yue Liu ◽  
Yanan Zhang ◽  
Jiao Qu
Keyword(s):  
Environmental Factors ◽  
Uv Irradiation ◽  
Water Environment ◽  
Oxidative Degradation ◽  
Environmental Risks ◽  
Important Process ◽  
Environmental Behaviors ◽  
Environmental Media ◽  
Different Types ◽  
Harmful Effects

Microplastics (MPs) are ubiquitous in environmental media, and their harmful effects on MPs on the ecosystem have attracted more and more attention. Once released into the environment, MPs can trigger oxidative degradation through ultraviolet (UV) to cause photoaging. Photoaging significantly affects the properties of MPs, which leads to changing their environmental behaviors and increasing environmental risks. In this review, the generation of MPs under UV irradiation and the influence of environmental factors on the photoaging of MPs were discussed. Photoaging of MPs is an important process affecting the migration, transformation and interaction of pollutants in water and soil. In order to fully predict the fate and environmental interaction of MPs, more researches are needed in the future to explore the photoaging behavior of different types of MPs under natural environmental conditions.

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