scholarly journals Electrical conductivity test for Serbian spruce seed quality estimation

2005 ◽  
pp. 127-133 ◽  
Author(s):  
Vladan Ivetic ◽  
Jelena Milovanovic
Keyword(s):  
Electrical Conductivity ◽  
Tree Species ◽  
Seed Quality ◽  
Germination Rate ◽  
Statistical Significance ◽  
Specific Electrical Conductivity ◽  
Model Species ◽  
Quality Estimation ◽  
Serbian Spruce

In this paper, for the firs time in our country, electrical conductivity test was used for seed quality estimation. Since this test is not standardized for most of tree species, main goal of this paper was to investigate possibility of its use for estimation of potential germination rate of Serbian spruce seed, like model species. Negative correlation with great statistical significance (r=-0.9003) was found between specific electrical conductivity and germination rate. On this basis, authors were give proposal for determination of Serbian spruce seed quality, after measuring of electrical conductivity. Results show great potential of this method for seed quality estimation, and justify further work on its standardization for Serbian spruce, and other tree species as well.

scholarly journals A Method For Determination Of Specific Electrical Resistance Of Steel And Nano-Coating Sputtered On It

2015 ◽  
Vol 2 ◽  
pp. 118 ◽  
Author(s):  
Andris Martinovs ◽  
Josef Timmerberg ◽  
Konstantins Savkovs ◽  
Aleksandrs Urbahs ◽  
Paul Beckmann
Keyword(s):  
Electrical Conductivity ◽  
Magnetic Permeability ◽  
Electrical Resistance ◽  
Skin Effect ◽  
Specific Electrical Resistance ◽  
Specific Electrical Conductivity ◽  
Relative Magnetic Permeability ◽  
Nano Coating ◽  
Cylindrical Steel

The paper describes methods developed to determine specific electrical conductivity and relative magnetic permeability of cylindrical steel items and nano-coatings deposited on them by sputtering. Research enables development of a new method for determination of thickness of vacuum deposited nano- coating that is based on application of skin effect.

Determination of the electrical conductivity of human liver metastases: impact on therapy planning in the radiofrequency ablation of liver tumors

2016 ◽  
Vol 58 (2) ◽  
pp. 164-169 ◽  
Author(s):  
Urte Zurbuchen ◽  
Franz Poch ◽  
Ole Gemeinhardt ◽  
Martin E Kreis ◽  
Stefan M Niehues ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Radiofrequency Ablation ◽  
Liver Metastasis ◽  
Liver Metastases ◽  
Liver Tissue ◽  
Colorectal Liver Metastases ◽  
Liver Tumors ◽  
Tissue Temperature ◽  
Specific Electrical Conductivity

Background Radiofrequency ablation is used to induce thermal necrosis in the treatment of liver metastases. The specific electrical conductivity of a liver metastasis has a distinct influence on the heat formation and resulting tumor ablation within the tissue. Purpose To examine the electrical conductivity σ of human colorectal liver metastases and of tumor-free liver tissue in surgical specimens. Material and Methods Surgical specimens from patients with resectable colorectal liver metastases were used for measurements (size of metastases <30 mm). A four-needle measuring probe was used to determine the electrical conductivity σ of human colorectal liver metastasis (n = 8) and tumor-free liver tissue (n = 5) in a total of five patients. All measurements were performed at 470 kHz, which is the relevant frequency for radiofrequency ablation. The tissue temperature was also measured. Hepatic resections were performed in accordance with common surgical standards. Measurements were performed in the operating theater immediately after resection. Results The median electrical conductivity σ was 0.57 S/m in human colorectal liver metastases at a median temperature of 35.1℃ and 0.35 S/m in tumor-free liver tissue at a median temperature of 34.9℃. The electrical conductivity was significantly higher in tumor tissue than in tumor-free liver tissue ( P = 0.005). There were no differences in tissue temperature between the two groups ( P = 0.883). Conclusion The electrical conductivity is significantly higher in human colorectal liver metastases than in tumor-free liver tissue at a frequency of 470 kHz.

scholarly journals Conditioning in the promotion and uniformization of Umbu seed germination

2018 ◽  
Vol 40 (1) ◽  
Author(s):  
Renato Teo Barros ◽  
Cibele Chalita Martins ◽  
Francisco Elder Carlos Bezerra Pereira ◽  
Givanildo Zildo da Silva
Keyword(s):  
Electrical Conductivity ◽  
Seed Germination ◽  
Water Content ◽  
Environmental Conditions ◽  
Seed Quality ◽  
Germination Rate ◽  
Ambient Conditions ◽  
Germination Test ◽  
Mean Germination Time ◽  
Cold Chamber

Abstract Seed dormancy may decrease during storage and some environmental conditions may accelerate this process. The aim of this work was to determine efficient techniques to condition umbu seeds in order to promote and standardize their germination. Seeds were stored for 180 days in paper bags kept in five ambient conditions: laboratory (25 ºC and 55% RH); warm oven (40 °C and 53% RH); hot oven (50 °C and 49% RH); dry chamber (18 °C and 65% RH) and cold chamber (10 °C and 65% RH). Seed quality was evaluated every 60 days by means of the following tests and determinations: water content; germination test (25 °C and 55% RH, weekly evaluated up to 91 days after sowing); first count test (14 days); germination rate index; mean germination time and electrical conductivity. The conditioning of umbu seeds in laboratory, or in warm oven (40 ºC) used efficient techniques to promote and standardize germination; under these conditions, after six months of storage, germination increased from 31% to 84 and 74%, respectively.

scholarly journals Application of independent-channel method for investigation of electrical conductivity of graphene-containing shungite.

2021 ◽  
Author(s):  
I.V. Antonets ◽  
◽  
E.A. Golubev ◽  
V.G. Shavrob ◽  
V.I. Shcheglov ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Electrical Conductivity ◽  
Spatial Distribution ◽  
Current Flow ◽  
Specific Conductivity ◽  
Specific Electrical Conductivity ◽  
Parallel Connection ◽  
Raster Electron Microscopy ◽  
Current Flows

The independent channel method which is intended for the calculation of specific electrical conductivity of graphene-contained shungite is proposed and realized on practice. It is noted that the most important of shungite application is the creation of screen hawing large area which are able to block electromagnetic radiation in wide frequency range. The most important factor which determines the blocking properties of shungite is the specific electrical conductivity of its carbon part which is determined by the spatial distribution of carbon atoms. As a main method of carbon structure investigation is mentioned the high-resolution raster electron microscopy which allows from the surface of specimen to receive the card of distribution of graphene slides and graphene packets. The spatial factor which determines the shungite conductivity is large anisotropy of single graphene slide which reaches three orders and more in the cases along and across the slide. The proposed method independent channels takes into consideration the arbitrary orientation of graphene packets relatively to direction of current flow. As a basis of method is employing the card of carbon spatial distribution which is received by raster electron microscopy method. The card is divided by parallel channels which transverse dimension is near or slightly exceeds the typical dimension of graphene packet. The channels are divided to square blocks which sides are equal to width of channel. The whole resistance of channel is formed by the successive connection of individual resistances of blocks. The resistance of whole card is determined by parallel connection of channels or averaging of resistance of all channels and following filling the whole area of card. The first step of analysis is the determination of advantage orientation of slides inside of every blocks. On the basis of determined orientation the block is filled by periodic structure which period is equal to the width of graphene slide and neighbouring interval. As a parameter which determines the orientation is used the angle between advantage orientation of graphene slides and axis of current flow between contacts. Owing to symmetry of task in comparison of current direction the limited meanings of corner is 0 and 90 degree. It is established two principal different cases of orientation: first – when determining angle is less than 45 degree and second when this angle is more than 45 degree. In the first case the current flows along the stripe with large conductivity. In the second case the current flows across these stripes so as through the stripes with low conductivity. It is found the smooth dependence of block resistivity from the angle of strip orientation. For the characteristic of area which is filled graphene slides it is proposed the coefficient of filling which is determined by binary discretization method. On the basis of analysis of slides orientation and filling coefficients are calculated the resistance of individual blocks. The resistances of all channels of investigated card are proposed. By using two methods – parallel connection and averaging over all channels it is calculated the specific electrical resistance and specific electrical conductivity of material as a whole. It is found that the received values of specific conductivity exceed the determined in experiment value in several (to 10) times. For the coordination of calculated value with experimental value it is made the variation of specific resistances of graphene slides and intervals between its. It id found that the calculation by method of parallel connection of channels ensures several better coordination than method of averaging. It is shown that the resistance is improved in the first turn by the increasing the resistance of interval between slides. In the quality of possible reason of decisive role of interval it is proposed the observed in experiment sharp non-homogeneity of relative arrangement of graphene slides. It is discussed the possible courses of further development of work. As a most important task it is proposed the more circumstantial determination of statistical character of received results.

scholarly journals Desempenho fisiológico de sementes de algodão cultivadas em Luís Eduardo Magalhães, Bahia

2015 ◽  
Vol 10 (2) ◽  
pp. 69
Author(s):  
R. T. C. Nunes ◽  
T. R. Prado ◽  
E. B. Ribeiro ◽  
W. S. Vale ◽  
O. M. Morais
Keyword(s):  
Electrical Conductivity ◽  
Gossypium Hirsutum ◽  
Seed Quality ◽  
Germination Rate ◽  
Dry Mass ◽  
State University ◽  
Seed Technology ◽  
Physiological Quality ◽  
Cotton Seeds

<p>O presente trabalho foi desenvolvido no laboratório de tecnologia de sementes da Universidade Estadual do Sudoeste da Bahia, Campus de Vitória da Conquista UESB, com objetivo de avaliar a qualidade fisiológica de sementes de algodão (<em>Gossypium hirsutum</em> L.), utilizando-se cinco cultivares (DP 604, FM 993, BRS 368, TMG 642 e DELTA OPAL). As sementes foram submetidas aos seguintes testes: teor de água, peso de mil sementes, germinação, primeira contagem de germinação, índice de velocidade de emergência, emergência, comprimento da parte aérea, massa seca das plântulas e condutividade elétrica. O delineamento experimental utilizado foi o inteiramente casualizado, em quatro repetições de 50 sementes por tratamento. A cultivar TMG 642 demonstrou baixa qualidade fisiológica das sementes, quando comparados com as cultivares DP 604, FM 993, BRS 368, e DELTA OPAL. Os testes de germinação, condutividade elétrica e índice de velocidade de germinação mostraram eficiência na separação de cultivares de sementes de algodão em níveis de vigor. </p><p align="center"><strong><em>Physiological performance of cottonseed grown in Luís Eduardo Magalhães, Bahia</em></strong></p><p><strong>ABSTRACT</strong><strong>: </strong>This study was conducted at the State University of seed technology laboratory of Southwest Bahia, Campus Victory Conquest, UESB, to evaluate the physiological quality of cotton seeds (<em>Gossypium hirsutum</em> L.), using five cultivars (DP 604, FM 993, BRS 368, GMT 642 and DELTA OPAL). Seeds were subjected to the following tests: water content, weight of a thousand seeds, germination, first count, emergence speed index, emergency, shoot length, dry mass of seedlings and electrical conductivity. The experimental design was completely randomized, with four replications of 50 seeds per treatment. The cultivar TMG 642 demonstrated low physiological seed quality when compared with the DP 604 cultivars, FM 993, BRS 368, and DELTA OPAL. Germination tests, electrical conductivity and germination rate index showed efficiency in the separation of cotton seed varieties in force levels.</p>

Determination of Effect of Salt Content in Cooling Liquid on the Result of Cable Capacitance per Unit Length Measurement

2015 ◽  
Vol 756 ◽  
pp. 546-551 ◽  
Author(s):  
Michael Grigoriev ◽  
G.V. Vavilova ◽  
Nadezda S. Starikova
Keyword(s):  
Electrical Conductivity ◽  
Production Line ◽  
Unit Length ◽  
Salt Content ◽  
Wave Resistance ◽  
Specific Electrical Conductivity ◽  
Electrical Method ◽  
Capacitance Transducer ◽  
The Impact

Capacitance per unit length and related wave resistance refer to the main characteristics of a number of cable products, such as communication cables, control cables or radio-frequency cables. The capacitance per unit length value is regulated by the standards for appropriate types of cables. This study describes the technical implementation of the electrical method of measuring of the capacitance per unit length of the electric cable directly on the production line. It is shown that the change in specific electrical conductivity of water, which a capacitance transducer is dipped into, has a significant impact on the outcome of in-process control of cable capacitance per unit length. A method of offset from the impact of this measurement on the control results is suggested.

scholarly journals Vigor of canola seeds through quantification of CO2 emission

2013 ◽  
Vol 37 (3) ◽  
pp. 229-236 ◽  
Author(s):  
João Alexandre Lopes Dranski ◽  
Artur Soares Pinto Júnior ◽  
Neusa Francisca Michelon Herzog ◽  
Ubirajara Contro Malavasi ◽  
Marlene de Matos Malavasi ◽  
...  
Keyword(s):  
Seed Quality ◽  
Germination Rate ◽  
Carbon Dioxide Concentration ◽  
Co2 Concentration ◽  
Mean Values ◽  
Seed Technology ◽  
Sowing Dates ◽  
Level Of Significance

Seed marks the beginning of grain production from cultivated crops. Ensuring seed quality is the priority in the field of seed technology. In this context, the purpose of this study was to evaluate the use of carbon dioxide concentration to Classify Brassica napus seed lots of different quality resulting from various sowing dates. Seed lots were evaluated by percentage of normal plantlets and the germination rate index. CO2 concentration was quantified in samples submitted to five periods of incubation at 40° C with the aid of a gas exchange analyzer coupled to an injection and airflow system. The results were subjected to analysis of variance and the mean values were compared by the Duncan test and by regression analysis at the 5% level of significance. B. napus seeds from all lots showed a high percentage of normal plantlets and germination rate index. Percentage of normal plantlets was correlated with CO2 concentration. Determination of the CO2 concentration was more efficient with three hours of incubation which allowed classification of canola seed lots into four vigor classes. CO2 concentration was inversely proportional to the percentage of normal plantlets.

scholarly journals Propagation of Pistacia lentiscus var. Chia Genotypes and Determination of Their Ornamental Traits Combined with a Genetic Analysis Using ISSR Markers

Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 205
Author(s):  
Stefanos Kostas ◽  
Stefanos Hatzilazarou ◽  
Elias Pipinis ◽  
Anastasios Vasileiadis ◽  
Panagiotis Magklaras ◽  
...  
Keyword(s):  
Genetic Analysis ◽  
Germination Rate ◽  
Leaf Traits ◽  
Issr Markers ◽  
Pistacia Lentiscus ◽  
Natural Habitats ◽  
Indolebutyric Acid ◽  
Single Male ◽  
Asexual Propagation

Pistacia lentiscus L. is a dioecious shrub or small tree with high drought resistance, native in the entire Mediterranean basin. The variety ‘Chia’ (mastic tree) is cultivated for the production of mastic gum (a resin produced after wounding of the trunks and thick branches) in the Island of Chios (Greece), but it also has a significant ornamental value. In the present study, ten male and ten female genotypes of P. lentiscus var. Chia from the natural habitats of Chios were selected and examined with respect to the rooting efficiency of their shoot cuttings. The germination ability of the seeds was also tested. The 20 plants were morphologically described, mainly with respect to traits related to their ornamental value. Furthermore, leaves were collected from the 20 genotypes, from which genomic DNA (gDNA) was isolated, followed by amplification of gDNA fragments using the polymerase chain reaction (PCR) and inter simple sequence repeat (ISSR) primers. This was done aiming both at the determination of their genetic distance and the establishment of possible correlations between the amplified bands and certain morphological traits. The results of the study showed that there were differences among the genotypes for both methods of propagation. Regarding the rooting of the shoot cuttings, the best genotype was 8M (cv. ‘Psilophyllos’), achieving a rooting rate of 62.5% in winter with the application of indolebutyric acid (potassium salt of IBA), while regarding the seed germination capacity the genotype 2F exhibited the highest germination rate (57%). Genetic analysis using ISSRs separated the plants into four groups, one group consisting of male genotypes, one of the female genotypes, one consisting of members from both genders and a fourth containing a single male genotype. The genetic analysis of the male genotypes only produced a dendrogram showing the cultivars clustering in three different groups. Regardless of the genetic analysis, it seems that there were correlations between the ISSR markers and the leaf traits and also the gender and the asexual propagation. These correlations can assist future breeding programs of P. lentiscus var. Chia.

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