scholarly journals Characterization of Silicone Oil used in HV Cable Sealing Ends

2019 ◽  
pp. 28-31
Author(s):  
S Virtanen ◽  
G. Callender ◽  
T. Andritsch ◽  
J Pilgrim ◽  
D Wheatley ◽  
...  
Keyword(s):  
Silicone Oil ◽  
Chemical Contaminants ◽  
Characterization Methods ◽  
Significant Difference ◽  
Structural Differences ◽  
Show Difference ◽  
Insulating Liquid ◽  
Moisture Potential ◽  
Hv Cable

Existing polymeric cable sealing end (CSE) typically contain silicone oil as an insulating liquid between the cable core and the outside of the CSE. In recent years, a number of performance issues have been identified with silicone oil filled CSEs. To understand the reasons for the observed behavior of silicone oil, a range of characterization methods are reviewed, to allow investigation of the influence of moisture, potential chemical contaminants and the compatibility with CSE materials. The water content of all the oils studied was above the limit given in IEC 60836 (2015) for new silicone oil. There is no significant difference between the moisture content, whether the oil is used in CSE or new. Neither did the Fourier infrared (FTIR) spectroscopic analysis show difference between the oils. Preliminary results from gas chromatography connected to mass spectrometer (GC/MS) clearly show structural differences between unused expired oil and new oil samples particularly that species suspected to be cyclic siloxane appear to be present in the expired sample.

scholarly journals Experimental Comparison of Three Characterization Methods for Two Phase Change Materials Suitable for Domestic Hot Water Storage

2021 ◽  
Vol 11 (21) ◽  
pp. 10229
Author(s):  
Maxime Thonon ◽  
Laurent Zalewski ◽  
Stéphane Gibout ◽  
Erwin Franquet ◽  
Gilles Fraisse ◽  
...  
Keyword(s):  
Phase Change ◽  
Phase Change Materials ◽  
Mass Density ◽  
Hot Water ◽  
Experimental Comparison ◽  
Two Phase ◽  
Characterization Methods ◽  
Domestic Hot Water ◽  
Significant Difference

This study presents an experimental comparison of three characterization methods for phase change materials (PCM). Two methods were carried out with a calorimeter, the first with direct scanning (DSC) and the second with step scanning (STEP). The third method is a fluxmetric (FM) characterization performed using a fluxmeter bench. For the three methods, paraffin RT58 and polymer PEG6000, two PCM suitable for domestic hot water (DHW) storage, were characterized. For each PCM, no significant difference was observed on the latent heat and the total energy exchanged between the three characterization methods. However, DSC and STEP methods did not enable the accurate characterization of the supercooling process observed with the FM method for polymer PEG6000. For PEG6000, the shape of the enthalpy curve of melting also differed between the experiments on the calorimeter—DSC and STEP—methods, and the FM method. Concerning the PCM comparison, RT58 and PEG6000 appeared to have an equivalent energy density but, as the mass density of PEG6000 is greater, more energy is stored inside the same volume for PEG6000. However, as PEG6000 experienced supercooling, the discharging temperature was lower than for RT58 and the material is therefore less adapted to DHW storage operating with partial phase change cycles where the PCM temperature does not decrease below 52 °C.

Caracterização da Peneira Média em Clones de Coffea canephora

REVISTA FIMCA ◽  
2018 ◽  
Vol 5 (2) ◽  
pp. 28-31
Author(s):  
Darlan Darlan Sanches Barbosa Alves ◽  
Victor Mouzinho Spinelli ◽  
Marcos Santana Moraes ◽  
Carolina Augusto De Souza ◽  
Rodrigo da Silva Ribeiro ◽  
...  
Keyword(s):  
Genetic Improvement ◽  
Block Design ◽  
Coffea Canephora ◽  
Coffee Production ◽  
Randomized Block Design ◽  
Significant Difference ◽  
The Mean ◽  
Four Blocks ◽  
Selection Of

Introdução: O estado de Rondônia se destaca como tradicional produtor de café, sendo o segundo maior produtor brasileiro de C. canephora. No melhoramento genético de C. canephora, a seleção de plantas de elevada peneira média está associada à bebida de qualidade superior. Objetivos: O objetivo desse estudo foi avaliar a variabilidade genética de clones de C. canephora para o tamanho dos grãos, mensurado a partir da avaliação da peneira média (PM). Materiais e Métodos: Para isso, foi conduzido ao longo de dois anos agrícolas experimento no campo experimental da Embrapa no município de Ouro Preto do Oeste-RO, para a avaliação da peneira média de 130 genótipos (clones) com características das variedades botânicas Conilon, Robusta e híbridos intervarietais. O delineamento experimental utilizado foi de blocos ao acaso, com quatro repetições de quatro plantas por parcela. Resultados: Não houve resultados significativos para a interação clones X anos, indicando uma maior consistência no comportamento das plantas ao longo do tempo. Porém foram observadas diferenças significativas para o tamanho dos grãos entre os genótipos avaliados, possibilitando selecionar genótipos superiores. Conclusão: Os genótipos agruparam-se em cinco classes de acordo com o teste de média, subsidiando a caracterização de um gradiente de variabilidade da característica avaliada ABSTRACTIntroduction: Coffea canephora accounts for approximately 35% of the world's coffee production. The state of Rondônia stands out as a traditional coffee producer, being the second largest Brazilian producer of C. canephora. In the classical genetic improvement of C. anephora, the selection of plants of high average sieve is associated with a drink of superior quality. Objectives: The objective of this udy was to evaluate the genetic variability of Coffea canephora clones for the agronomic medium sieve (PM). Materials and Methods: The experiment was conducted in the experimental field of Embrapa, municipality of OuroPreto do Oeste-RO, located at coordinates 10º44'53 "S and 62º12'57". One hundred thirty genotypes (clones) of botanical characteristics Conilon, Robusta and intervarietal hybrids were evaluated in the agricultural years 2013-2014 and 2014-2015. The experimental design was a randomized block design with four blocks and four plants per plot, spacing 3.5 x 1.5 meters between plants. Results: Significant difference was found for the grain size. According to the F test, at 5% probability, the genotypes were grouped into five classes according to the mean test. Conclusion: The results obtained subsidized the characterization of a variability gradient of the evaluated trait.

scholarly journals A global non-invasive methodology for the phenotyping of potato under water deficit conditions using imaging, physiological and molecular tools

Plant Methods ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
M. Musse ◽  
G. Hajjar ◽  
N. Ali ◽  
B. Billiot ◽  
G. Joly ◽  
...  
Keyword(s):  
Water Stress ◽  
Water Deficit ◽  
Soil Conditions ◽  
Growth Stages ◽  
Dry Matter Content ◽  
Tuber Growth ◽  
Non Invasive ◽  
Potato Plants ◽  
Significant Difference

Abstract Background Drought is a major consequence of global heating that has negative impacts on agriculture. Potato is a drought-sensitive crop; tuber growth and dry matter content may both be impacted. Moreover, water deficit can induce physiological disorders such as glassy tubers and internal rust spots. The response of potato plants to drought is complex and can be affected by cultivar type, climatic and soil conditions, and the point at which water stress occurs during growth. The characterization of adaptive responses in plants presents a major phenotyping challenge. There is therefore a demand for the development of non-invasive analytical techniques to improve phenotyping. Results This project aimed to take advantage of innovative approaches in MRI, phenotyping and molecular biology to evaluate the effects of water stress on potato plants during growth. Plants were cultivated in pots under different water conditions. A control group of plants were cultivated under optimal water uptake conditions. Other groups were cultivated under mild and severe water deficiency conditions (40 and 20% of field capacity, respectively) applied at different tuber growth phases (initiation, filling). Water stress was evaluated by monitoring soil water potential. Two fully-equipped imaging cabinets were set up to characterize plant morphology using high definition color cameras (top and side views) and to measure plant stress using RGB cameras. The response of potato plants to water stress depended on the intensity and duration of the stress. Three-dimensional morphological images of the underground organs of potato plants in pots were recorded using a 1.5 T MRI scanner. A significant difference in growth kinetics was observed at the early growth stages between the control and stressed plants. Quantitative PCR analysis was carried out at molecular level on the expression patterns of selected drought-responsive genes. Variations in stress levels were seen to modulate ABA and drought-responsive ABA-dependent and ABA-independent genes. Conclusions This methodology, when applied to the phenotyping of potato under water deficit conditions, provides a quantitative analysis of leaves and tubers properties at microstructural and molecular levels. The approaches thus developed could therefore be effective in the multi-scale characterization of plant response to water stress, from organ development to gene expression.

scholarly journals Crystallization of Random Metallocene-Catalyzed Propylene-Based Copolymers with Ethylene and 1-Hexene on Rapid Cooling

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2091
Author(s):  
Daniela Mileva ◽  
Jingbo Wang ◽  
René Androsch ◽  
Katalee Jariyavidyanont ◽  
Markus Gahleitner ◽  
...  
Keyword(s):  
Mechanical Performance ◽  
Metallocene Catalyst ◽  
Nucleating Agent ◽  
Random Copolymers ◽  
Rapid Cooling ◽  
Significant Difference ◽  
Chip Calorimetry ◽  
High Cooling Rates ◽  
Fast Scanning Chip Calorimetry

Propylene-based random copolymers with either ethylene or 1-hexene as comonomer, produced using a metallocene catalyst, were studied regarding their crystallization behaviors, with a focus on rapid cooling. To get an impression of processing effects, fast scanning chip calorimetry (FSC) was used in addition to the characterization of the mechanical performance. When comparing the comonomer type and the relation to commercial grades based on Ziegler–Natta-type catalysts, both an interaction with the catalyst-related regio-defects and a significant difference between ethylene and 1-hexene was observed. A soluble-type nucleating agent was found to modify the behavior, but to an increasingly lesser degree at high cooling rates.

scholarly journals Integration of Dental Implants in Conjunction with EDTA-Conditioned Dentin Grafts: An Experimental Study

2021 ◽  
Vol 9 (6) ◽  
pp. 63
Author(s):  
Payam Farzad ◽  
Ted Lundgren ◽  
Adel Al-Asfour ◽  
Lars Andersson ◽  
Christer Dahlin
Keyword(s):  
Direct Contact ◽  
Mineral Content ◽  
X Rays ◽  
X Ray ◽  
Dentin Surface ◽  
Significant Difference ◽  
C And N ◽  
Micro Implants ◽  
Demineralized Dentin

This study was undertaken to investigate the integration of titanium micro-implants installed in conjunction with previously dentin-grafted areas and to study the morphological appearance, mineral content, and healing pattern of xenogenic EDTA-conditioned dentin blocks and granules grafted to cavities in the tibial bone of rabbits. Demineralized and non-demineralized dentin blocks and granules from human premolars were implanted into cavities prepared on the lateral aspects of the tibias of rabbits. After a healing period of six months, micro-implants were installed at each surgical site. Histological examinations were carried out after 24 weeks. Characterization of the EDTA-conditioned dentin blocks was performed by means of light microscopy, dental X-rays, scanning electron microscopy, and energy dispersive X-ray analysis (EDX). No implants were found to be integrated in direct contact with the dentin particles or blocks. On the EDTA-conditioned dentin surface, the organic marker elements C and N dominated, as revealed by EDX. The hydroxyapatite constituents Ca and P were almost absent on the dentin surface. No statistically significant difference was observed between the EDTA-conditioned and non-demineralized dentin, as revealed by BIC and BA. The bone-inductive capacity of the dentin material seemed limited, although demineralization by means of EDTA indicated higher BIC and BA values in conjunction with the installed implants in the area. A 12 h EDTA treatment did not fully decalcify the grafts, as revealed by X-ray analysis.

scholarly journals Design of a force-measuring setup for colorectal compression anastomosis and first ex-vivo results

2021 ◽  
Author(s):  
Jana Steger ◽  
Isabella Patzke ◽  
Maximilian Berlet ◽  
Stefanie Ficht ◽  
Markus Eblenkamp ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Tissue Fixation ◽  
Force Transmission ◽  
Tissue Thickness ◽  
Colon Tissue ◽  
Device Development ◽  
Compression Anastomosis ◽  
Technical Requirements ◽  
Significant Difference

Abstract Purpose The introduction of novel endoscopic instruments is essential to reduce trauma in visceral surgery. However, endoscopic device development is hampered by challenges in respecting the dimensional restrictions, due to the narrow access route, and by achieving adequate force transmission. As the overall goal of our research is the development of a patient adaptable, endoscopic anastomosis manipulator, biomechanical and size-related characterization of gastrointestinal organs are needed to determine technical requirements and thresholds to define functional design and load-compatible dimensioning of devices. Methods We built an experimental setup to measure colon tissue compression piercing forces. We tested 54 parameter sets, including variations of three tissue fixation configurations, three piercing body configurations (four, eight, twelve spikes) and insertion trajectories of constant velocities (5 mms−1, 10 mms−1,15 mms−1) and constant accelerations (5 mms−2, 10 mms−2, 15 mms−2) each in 5 samples. Furthermore, anatomical parameters (lumen diameter, tissue thickness) were recorded. Results There was no statistically significant difference in insertion forces neither between the trajectory groups, nor for variation of tissue fixation configurations. However, we observed a statistically significant increase in insertion forces for increasing number of spikes. The maximum mean peak forces for four, eight and twelve spikes were 6.4 ± 1.5 N, 13.6 ± 1.4 N and 21.7 ± 5.8 N, respectively. The 5th percentile of specimen lumen diameters and pierced tissue thickness were 24.1 mm and 2.8 mm, and the 95th percentiles 40.1 mm and 4.8 mm, respectively. Conclusion The setup enabled reliable biomechanical characterization of colon material, on the base of which design specifications for an endoscopic anastomosis device were derived. The axial implant closure unit must enable axial force transmission of at least 28 N (22 ± 6 N). Implant and applicator diameters must cover a range between 24 and 40 mm, and the implant gap, compressing anastomosed tissue, between 2 and 5 mm.

scholarly journals Poultry Production in Nepal: Characteristics, Productivity and Constraints

2017 ◽  
Vol 5 (2) ◽  
pp. 222-226 ◽  
Author(s):  
Rajani Osti ◽  
Dinesh Bhattarai ◽  
Harshika Chaudhary ◽  
Virendra Singh
Keyword(s):  
Egg Production ◽  
Marketing Channel ◽  
Site Investigation ◽  
Chronic Respiratory Disease ◽  
Poultry Production ◽  
Poultry Products ◽  
Significant Difference ◽  
Ranking Technique ◽  
Poultry Farming

Poultry farming is integral part of agriculture in Nepal. The objective of this research was to analyze the prevailing production constraints, characterization of poultry farming and its economic analysis using questionnaire-based survey and on-site investigation. 180 farms were selected from 3 major districts. Garrett’s ranking technique was used to analyze the constraints.  Highly significant difference (P<0.01) in size of poultry farm was found. We found significant difference in feeding, housing and drinking system for the chicken. Un-organized chicken marketing channel was observed in the study area.   High chicks’ mortality, wastage of feed, insecure vaccination and frequent drop in egg production were characteristic of laying hens. Newcastle disease and Chronic Respiratory Disease were acknowledged as the biggest constraint of chicken production. Government and concerned agencies need to take active part for the extension service to strengthen the health of chicken and organized marketing channel is essential for selling of poultry products  which can improve the profit to the farmers.Int. J. Appl. Sci. Biotechnol. Vol 5(2): 222-226

scholarly journals Conjuring up a ghost: structural and functional characterization of FhuF, a ferric siderophore reductase from E. coli

2021 ◽  
Author(s):  
I. B. Trindade ◽  
G. Hernandez ◽  
E. Lebègue ◽  
F. Barrière ◽  
T. Cordeiro ◽  
...  
Keyword(s):  
Functional Characterization ◽  
Paramagnetic Nmr ◽  
E Coli ◽  
The Past ◽  
Internal Cavities ◽  
Structural Differences ◽  
Bond Strengths ◽  
Redox Bohr Effect ◽  
Micromolar Range

AbstractIron is a fundamental element for virtually all forms of life. Despite its abundance, its bioavailability is limited, and thus, microbes developed siderophores, small molecules, which are synthesized inside the cell and then released outside for iron scavenging. Once inside the cell, iron removal does not occur spontaneously, instead this process is mediated by siderophore-interacting proteins (SIP) and/or by ferric-siderophore reductases (FSR). In the past two decades, representatives of the SIP subfamily have been structurally and biochemically characterized; however, the same was not achieved for the FSR subfamily. Here, we initiate the structural and functional characterization of FhuF, the first and only FSR ever isolated. FhuF is a globular monomeric protein mainly composed by α-helices sheltering internal cavities in a fold resembling the “palm” domain found in siderophore biosynthetic enzymes. Paramagnetic NMR spectroscopy revealed that the core of the cluster has electronic properties in line with those of previously characterized 2Fe–2S ferredoxins and differences appear to be confined to the coordination of Fe(III) in the reduced protein. In particular, the two cysteines coordinating this iron appear to have substantially different bond strengths. In similarity with the proteins from the SIP subfamily, FhuF binds both the iron-loaded and the apo forms of ferrichrome in the micromolar range and cyclic voltammetry reveals the presence of redox-Bohr effect, which broadens the range of ferric-siderophore substrates that can be thermodynamically accessible for reduction. This study suggests that despite the structural differences between FSR and SIP proteins, mechanistic similarities exist between the two classes of proteins. Graphic abstract

scholarly journals Structural differences and the presence of unsubstituted amino groups in heparan sulphates from different tissues and species

1997 ◽  
Vol 322 (2) ◽  
pp. 499-506 ◽  
Author(s):  
Toshihiko TOIDA ◽  
Hisao YOSHIDA ◽  
Hidenao TOYODA ◽  
Ichiro KOSHIISHI ◽  
Toshio IMANARI ◽  
...  
Keyword(s):  
Acid Content ◽  
Heparan Sulphate ◽  
Kidney Medulla ◽  
Isolation And Characterization ◽  
Iduronic Acid ◽  
Structural Differences ◽  
Liver And Kidney ◽  
High Degree ◽  
Different Tissues

This study presents a comparison of heparan sulphate chains isolated from various porcine and bovine tissues. 1H-NMR spectroscopy (500 MHz) was applied for structural and compositional studies on intact heparan sulphate chains. After enzymic digestion of heparan sulphate using heparin lyase I (EC 4.2.2.7) II and III (EC 4.2.2.8), the compositions of unsaturated disaccharides obtained were determined by analytical capillary electrophoresis. Correlations between the N-sulphated glucosamine residues and O-sulphation and between iduronic acid content and total sulphation were discovered using the data obtained by NMR and disaccharide analysis. Heparan sulphate chains could be classified into two groups based on the sulphation degree and the iduronic acid content. Heparan sulphate chains with a high degree of sulphation possessed also a significant number of iduronic acid residues and were isolated exclusively from porcine brain, liver and kidney medulla. The presence and amount of N-unsubstituted glucosamine residues (GlcNp) was established in all of the heparan sulphates examined. The structural context in which this residue occurs was demonstrated to be: high sulphation domain → 4)-β-d-GlcAp-(1 → 4)-α-d-GlcNp-(1 → 4)-β-d-GlcAp-(1 → low sulphation domain (where GlcNp is 2-amino-2-deoxyglucopyranose, and GlcAp is glucopyranosyluronic acid), based on the isolation and characterization of a novel, heparin lyase III-derived, GlcNp containing tetrasaccharide and hexasaccharide. The results presented suggest that structural differences may play a role in important biological events controlled by heparan sulphate in different tissues.

scholarly journals Emerging techniques in the isolation and characterization of extracellular vesicles and their roles in cancer diagnostics and prognostics

The Analyst ◽  
2016 ◽  
Vol 141 (2) ◽  
pp. 371-381 ◽  
Author(s):  
Vijaya Sunkara ◽  
Hyun-Kyung Woo ◽  
Yoon-Kyoung Cho
Keyword(s):  
Extracellular Vesicles ◽  
Cancer Diagnostics ◽  
Clinical Implementation ◽  
Characterization Methods ◽  
Cancer Management ◽  
Isolation And Characterization

We present an overview of current isolation, detection, and characterization methods of extracellular vesicles and their applications and limitations as a potential emerging biomarker in cancer management and their clinical implementation.

Sign in / Sign up

Export Citation Format

Share Document