scholarly journals THE ROLE OF FIBERS SURFACE IN DEVELOPMENT OF PAPERMAKING PROPERTIES OF TECHNICAL PULP IN THE REFINING PROCESS

2018 ◽  
pp. 207-216
Author(s):  
Иван (Ivan) Владимирович (Vladimirovich) Лебедев (Lebedev) ◽  
Яков (Yakov) Владимирович (Vladimirovich) Казаков (Kazakov) ◽  
Дмитрий (Dmitrij) Германович (Germanovich) Чухчин (Chukhchin) ◽  
Кристина (Kristina) Александровна (Аleksandrovna) Романенко (Romanenko)
Keyword(s):  
Specific Surface ◽  
Quantitative Data ◽  
Lignin Content ◽  
Fiber Surface ◽  
Refining Process ◽  
Just Noticeable Difference ◽  
Quality Data ◽  
Sem Images ◽  
Degree Of Refining ◽  
The Relationship

The aim of this work was to determine the relationship between the values of the fiber specific surface and papermaking properties of the pulp that are changing in the refining process. Quality data on the status and quantitative data on the value of the fibers specific surface for softwood and hardwood kraft pulp with different lignin content and different degree of refining were obtained. When preparing samples was used technology of cryofixation and freeze-drying the wet laboratory samples. The SEM-images of the cellulose fibers surface in the state such as for the sheet forming, obtained on scanning electron microscope ZEISS "SIGMA VP". The SEM-images shows just noticeable difference in development of the fibers surface in the beating process. This is manifested in an increase in the number of microfibrils on the fiber surface. Quantitative data were obtained on the automatic analyzer of the specific surface magnitude ASAP. A visually apparent increase of the surface when beating technical cellulose confirmed quantitatively. The value of the specific surface area increased from 2 m2/g for cellulose after the dispergation into pulp of up to 4...6 m2/g after refining up to 60 °SR. Removal of lignin from cellulose promotes more intensive development of the surface during refining.For different kinds of pulp, similar dependences of physical-mechanical properties (interfiber bonding forces, bulk density, modulus of elasticity) of laboratory samples and specific surface data, which change during refining, are established.The main influence on the change in the structural-dimensional and elastic properties of paper during refining is exerted by an increase in the content of microfibrils on the outer surface of the fibers. The tightness of the correlation and the nature of the observed dependence depends on the wood species from which the cellulose is derived, on the lignin content of the samples, and on the drying method. For softwood pulp, the tightness of the relationship is higher than for hardwood pulp.

Learning Language Levels in Students Accurate with a History Academic Achievement History

2017 ◽  
Vol 1 (2) ◽  
pp. 137
Author(s):  
Noorlela Binti Noordin ◽  
Abdul Razaq Ahmad ◽  
Anuar Ahmad
Keyword(s):  
Academic Achievement ◽  
Statistical Inference ◽  
Quantitative Data ◽  
Quantitative Methods ◽  
Descriptive Statistics ◽  
Language Test ◽  
The Subject ◽  
The Difference ◽  
Learning Language ◽  
The Relationship

This study was aimed to evaluate the Malay proficiency among students in Form Two especially non-Malay students and its relationship to academic achievement History. To achieve the purpose of the study there are two objectives, the first is to look at the difference between mean of Malay Language test influences min of academic achievement of History subject among non-Malay students in Form Two and the second is the relationship between the level of Malay proficiency and their academic achievement for History. This study used quantitative methods, which involved 100 people of Form Two non-Malay students in one of the schools in Klang, Selangor. This study used quantitative data were analyzed using descriptive statistics and statistical inference with IBM SPSS Statistics v22 software. This study found that there was a relationship between the proficiency of Malay language among non-Malay students with achievements in the subject of History. The implications of this study are discussed in this article.

scholarly journals The relationship between physical fitness attributes and sports injury in female, team ball sport players: a systematic review

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Jessica B. Farley ◽  
Lily M. Barrett ◽  
Justin W. L. Keogh ◽  
Carl T. Woods ◽  
Nikki Milne
Keyword(s):  
Systematic Review ◽  
Body Composition ◽  
Physical Fitness ◽  
Sports Injury ◽  
Quality Data ◽  
Body Region ◽  
Ankle Sprains ◽  
Level Of Evidence ◽  
Data Synthesis ◽  
The Relationship

Abstract Background Understanding the relationships between physical fitness characteristics and sports injury may assist with the development of injury minimisation programs. The purpose of this systematic review was to investigate the association between physical fitness attributes and sports injury in female, team ball sport players. Methods Four scientific databases (MEDLINE, EMBASE, SPORTDiscus, Scopus) and reference lists of relevant research were searched for eligible studies up to September 2, 2019. Full-text articles examining the relationship between physical fitness and sports injury in female, team ball sport players were included. A modified Downs and Black checklist was used to assess methodological quality. Data synthesis determined summary conclusions based on the number of significant relationships divided by the total relationships investigated and reported as a percentage. Level of certainty was identified for summary conclusions based on level of evidence. Sub-analyses regarding competition level, age, and single injury types were also conducted. Results A total of 44 studies were included. Data synthesis revealed no associations (low to moderate certainty) between body composition (1/9; 11%), flexibility (18–20%), and balance (2/8; 25%) and ‘any injury’ classification. No associations (mostly of moderate certainty) were found between flexibility (0–27%), muscular strength (0–27%), and body composition (14–33%) and various body region injury classifications, whereas mixed summary conclusions were shown for balance (0-48%). Many associations between physical fitness and sports injury were deemed ‘unknown’ or with an insufficient level of certainty. Sub-analyses revealed no association between strength and noncontact ACL injuries (0/5; 0%) or ankle sprains (0/12; 0%), and between flexibility and ankle sprains (1/5; 20%); however, insufficient certainty of these results exists. Clear associations were concluded between balance and lower body injuries in female, non-elite (10/16; 63%) and junior (9/12; 75%) team ball sport players, with moderate and insufficient certainty of these results, respectively. Conclusion Limited evidence is available to demonstrate relationships between physical fitness and sports injury in female, team ball sport players. High-quality evidence investigating the multifactorial nature of sports injury, including the interactions physical fitness qualities have with other injury determinants, is needed to better understand the role of physical fitness in minimising sports injuries in female, team ball sport players. Trial Registration CRD42017077374 (PROSPERO on September 14, 2017).

scholarly journals Choice, quality and patients’ experience: evidence from a Finnish physiotherapy service

2021 ◽  
Author(s):  
Visa Pitkänen ◽  
Ismo Linnosmaa
Keyword(s):  
Positive Relationship ◽  
Competitive Bidding ◽  
Quality Data ◽  
Rehabilitation Service ◽  
Quality Information ◽  
Conditional Logit ◽  
Provider Quality ◽  
Disabled Patients ◽  
Patients Experience ◽  
The Relationship

AbstractWe study the relationship between patient choices and provider quality in a rehabilitation service for disabled patients who receive the service frequently but do not have access to quality information. Previous research has found a positive relationship between patient choices and provider quality in health services that patients typically do not have previous experience or use frequently. We contribute by examining choices of new patients and experienced patients who were either forced to switch or actively switched their provider. In the analysis, we combine register data on patients’ choices and switches with provider quality data from a competitive bidding, and estimate conditional logit choice models. The results show that all patients prefer high-quality providers within short distances. We find that the willingness to travel for quality is highest among new patients and active switchers. These results suggest that new patients and active switchers compare different alternatives more thoroughly, whereas forced switchers choose their new provider in limited time leading into poorer choices.

scholarly journals Effect of Glycero-(9,10-trioxolane)-trialeate on the Physicochemical Properties of Non-Woven Polylactic Acid Fiber Materials

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2517
Author(s):  
Anatoliy Olkhov ◽  
Olga Alexeeva ◽  
Marina Konstantinova ◽  
Vyacheslav Podmasterev ◽  
Polina Tyubaeva ◽  
...  
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Polylactic Acid ◽  
Specific Surface Area ◽  
Water Sorption ◽  
Fiber Surface ◽  
High Water ◽  
Scanning Calorimetry ◽  
Fiber Mats ◽  
Fiber Materials

Biocompatible glycero (9,10-trioxolane) trioleate (ozonide of oleic acid triglyceride, OTOA) was incorporated into polylactic acid (PLA) fibers by electrospinning and nonwoven PLA mats with 1%, 3% and 5% OTOA content. The morphological, mechanical, thermal and water sorption properties of electrospun PLA mats after the addition of OTOA were studied. A morphological analysis showed that the addition of OTOA increased the average fiber diameter and induced the formation of pores on the fiber surface, leading to an increase in the specific surface area for OTOA-modified PLA fibrous mats. PLA fiber mats with 3% OTOA content were characterized by a highly porous surface morphology, an increased specific surface area and high-water sorption. Differential scanning calorimetry (DSC) was used to analyze the thermal properties of the fibrous PLA mats. The glass transition temperatures of the fibers from the PLA–OTOA composites decreased as the OTOA content increased, which was attributed to the plasticizing effect of OTOA. DSC results showed that OTOA aided the PLA amorphization process, thus reducing the crystallinity of the obtained nonwoven PLA–OTOA materials. An analysis of the mechanical properties showed that the tensile strength of electrospun PLA mats was improved by the addition of OTOA. Additionally, fibrous PLA mats with 3% OTOA content showed increased elasticity compared to the pristine PLA material. The obtained porous PLA electrospun fibers with the optimal 3% OTOA content have the potential for various biomedical applications such as drug delivery and in tissue engineering.

scholarly journals Tubular Electrospun Vancomycin-Loaded Vascular Grafts: Formulation Study and Physicochemical Characterization

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2073
Author(s):  
Rossella Dorati ◽  
Enrica Chiesa ◽  
Mariella Rosalia ◽  
Silvia Pisani ◽  
Ida Genta ◽  
...  
Keyword(s):  
Methylene Chloride ◽  
Physicochemical Characterization ◽  
Fiber Surface ◽  
Solvent System ◽  
Burst Release ◽  
Sem Images ◽  
Composition And Structure ◽  
Medical Healthcare ◽  
Local Release ◽  
Preformulation Study

This work aimed at formulating tubular grafts electrospun with a size < 6 mm and incorporating vancomycin as an antimicrobial agent. Compared to other papers, the present study succeeded in using medical healthcare-grade polymers and solvents permitted by ICH Topic Q3C (R4). Vancomycin (VMC) was incorporated into polyester synthetic polymers (poly-L-lactide-co-poly-ε-caprolactone and poly lactide-co-glycolide) using permitted solvents; moreover, a surfactant was added to the formulation in order to avoid the precipitation of VMC on fiber surface. A preliminary preformulation study was carried out to evaluate solubility of VMC in different aqueous and organic solvents and its stability. To reduce size of fibers and their orientation, we studied a solvent system based on methylene chloride and acetone (DCM/acetone), at different ratios (80:20, 70:30, and 60:40). Considering conductivity of solutions and their spinnability, solvent system at a 80:20 ratio was selected for the study. SEM images demonstrated that size of fibers, their distribution, and their orientation were affected by the incorporation of VMC and surfactant into polymer solution. Surfactant allowed for the reduction of precipitates of VMC on fiber surface, which are responsible of the high burst release in the first six hours; the release was mainly dependent on graft structure porosity, number of pores, and graft absorbent capability. A controlled release of VMC was achieved, covering a period from 96 to 168 h as a function of composition and structure; the concentration of VMC was significantly beyond VMC minimum inhibitory concentration (MIC, 2 ug/mL). These results indicated that the VMC tubular electrospun grafts not only controlled the local release of VMC, but also avoided onset of antibiotic resistance.

The potential digestibility of cellulose in grasses and its relationship with chemical and anatomical parameters

1972 ◽  
Vol 78 (3) ◽  
pp. 457-464 ◽  
Author(s):  
R. J. Wilkins
Keyword(s):  
Floral Development ◽  
Lignin Content ◽  
Leaf Sheath ◽  
Vascular Bundles ◽  
Cellulose Digestibility ◽  
Wimmera Ryegrass ◽  
Rate Of Decline ◽  
The Relationship ◽  
Anatomical Parameters

SUMMARYPotential cellulose digestibility, measured by incubation in vitrofor 6 days, decreased during floral development in perennial ryegrass, Wimmera ryegrass, cocksfoot, oat and tall fescue. The rate of decline was slower than for cellulose digestibility measured after incubation in vitro for 2 days only. Morphological fractions ranked in order of descending potential cellulose digestibility – leaf blade, inflorescence, leaf sheath and stem.Lignin content was determined chemically by the method of Van Soest (1963) and lignified tissue was assessed by staining transverse sections of leaf blades and leaf sheaths with safranin and fast green. Both lignin and lignified tissue increased with maturity. Lignified tissue increased mainly through increase in the number of scleren-chyma cells, but was also affected by the formation of lacunae or cavities between the vascular bundles in leaf blades of cocksfoot and in leaf sheaths of all species studied. For 19 samples of leaf blades and leaf sheaths, potential cellulose digestibility had significant negative correlations with both lignin content (r = -0·862) and lignified tissue (r = -0·905). Limitations to the techniques used to assess lignification and further factors which may affect the relationship between lignification and potential cellulose digestibility are discussed.

War of words: the impact of Russian state television on the Russian Internet

2015 ◽  
Vol 43 (4) ◽  
pp. 533-555 ◽  
Author(s):  
Christina Cottiero ◽  
Katherine Kucharski ◽  
Evgenia Olimpieva ◽  
Robert W. Orttung
Keyword(s):  
World War Ii ◽  
Quantitative Data ◽  
The Internet ◽  
Strong Impact ◽  
World War ◽  
Search Query ◽  
Internet Users ◽  
Russian State ◽  
The Impact ◽  
The Relationship

How effective is Russian state television in framing the conflict in Ukraine that began with the Euromaidan protests and what is its impact on Russian Internet users? We carried out a content analysis of Dmitrii Kiselev's “News of the Week” show, which allowed us to identify the two key frames he used to explain the conflict – World War II-era fascism and anti-Americanism. Since Kiselev often reduces these frames to buzzwords, we were able to track the impact of these words on Internet users by examining search query histories on Yandex and Google and by developing quantitative data to complement our qualitative analysis. Our findings show that much of what state media produces is not effective, but that the “fascist” and anti-American frames have had lasting impacts on Russian Internet users. We argue that it does not make sense to speak of competition between a “television party” and an “Internet party” in Russia since state television has a strong impact in setting the agenda for the Internet and society as a whole. Ultimately, the relationship between television and the Internet in Russia is a continual loop, with each affecting the other.

Boards of Governors' Roles and Management of Government Aided Secondary Schools in Kyenjojo District, Uganda

2018 ◽  
Vol 1 (2) ◽  
pp. 138-150
Author(s):  
Hellen Kabasinguzi Wataba ◽  
Nafiu Lukman Abiodun
Keyword(s):  
Secondary Schools ◽  
Significant Relationship ◽  
Quantitative Data ◽  
Qualitative Data ◽  
Head Teachers ◽  
Correlational Research ◽  
Interview Guide ◽  
Major Predictor ◽  
And Control ◽  
The Relationship

This study sought to establish the relationship between boards of governors' (BOGs) roles and management of government aided secondary schools in Kyenjojo District. The objectives were to establish the relationship between BOGs' planning role and management of government aided secondary schools, to establish the relationship between BOGs' supervisory role and management of government aided secondary schools, to establish the relationship between BOGs' control role and management of government aided secondary schools; and to determine the major predictor of management of government aided secondary schools out of the three aspects of BOGs' roles. A correlational research design was used. A total of 90 respondents drawn from 108 BOGs and nine head teachers were selected as sample for the study using stratified random sampling and census inquiry respectively. The instruments used were questionnaire and interview guide. Quantitative data was analysed using Pearson product-moment correlation and regression, while thematic analysis was used on qualitative data. The study found a statistically moderate positive and significant relationship between BOGs' planning role and management of government aided secondary schools (r=.626, p=.000); a statistically moderate positive and significant relationship between BOGs' supervisory role and management of government aided secondary schools(r=.591, p=.000); and a statistically weak positive and significant relationship between BOGs' control role and management of government aided secondary schools(r=.280, p=.015). All the three aspects of BOGs roles account for 38.4% of the influence on management of government aided secondary schools in Kyenjojo district (adjusted r2=0.384, p=.000). The researchers recommend that BOGs should be well trained in management of schools in order to be effective in their work. Head teachers should not be dictators but create a conducive climate for planning, supervision and control by the BOGs.

Improving the efficiency of enzymatic hydrolysis of Eucalyptus residues with a modified aqueous ammonia soaking method

2018 ◽  
Vol 33 (2) ◽  
pp. 165-174 ◽  
Author(s):  
Dan Huo ◽  
Qiulin Yang ◽  
Guigan Fang ◽  
Qiujuan Liu ◽  
Chuanling Si ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Enzymatic Hydrolysis ◽  
Aqueous Ammonia ◽  
Pulp Mill ◽  
Fiber Surface ◽  
Raw Material ◽  
Sem Images ◽  
Aqueous Ammonia Soaking ◽  
Guaiacyl Lignin ◽  
Hydrolysis Of

Abstract Eucalyptus residues from pulp mill were pretreated with aqueous ammonia soaking (AAS) method to improve the efficiency of enzymatic hydrolysis. The optimized condition of AAS was obtained by response surface methodology. Meanwhile, hydrogen peroxide was introduced into the AAS system to modify the AAS pretreatment (AASP). The results showed that a fermentable sugar yield of 64.96 % was obtained when the eucalypt fibers were pretreated at the optimal conditions, with 80 % of ammonia (w/w) for 11 h and keeping the temperature at 90 °C. In further research it was found that the addition of H2O2 to the AAS could improve the pretreatment efficiency. The delignification rate and enzymatic digestibility were increased to 64.49 % and 73.85 %, respectively, with 5 % of hydrogen peroxide being used. FTIR analysis indicated that most syringyl and guaiacyl lignin and a trace amount of xylan were degraded and dissolved during the AAS and AASP pretreatments. The CrI of the raw material was increased after AAS and AASP pretreatments, which was attributed to the removal of amorphous portion. SEM images showed that microfibers were separated and explored from the initial fiber structure after AAS pretreatment, and the AASP method could improve the destructiveness of the fiber surface.

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