Impedance Measurement of Thallus Moisture Content in Lichens

1991 ◽  
Vol 23 (1) ◽  
pp. 77-84 ◽  
Author(s):  
Darwyn S. Coxson
Keyword(s):  
Moisture Content ◽  
Water Content ◽  
Physiological Activity ◽  
Impedance Measurement ◽  
Intermediate Water ◽  
Data Logger ◽  
Indirect Determination ◽  
Water Potentials ◽  
Water Films

AbstractThe indirect determination of water content in lichen thalli by means of impedance measurement is described. This technique applies an alternating current between small clips placed at the margins of lichen thalli. Two zones of sensitivity were apparent in measurements with the foliose lichen Xanthoparmelia chlorochroa. Ready discrimination was provided between fully saturated thalli and thalli with standing surface water films. Similarly, this technique proved highly accurate as a measurement of thallus moisture content at water potentials of –2·5 MPa and less (between 0 and 40% water content by weight in X. chlorochroa). Resolution was lower at intermediate water contents (c. 60–100Δ water content by weight), although general trends were still clearly evident. This technique is ideally suited for unattended measurements of water potential in lichens using currently available data–logger technology and provides high resolution within the range of water potentials crucial to the control of physiological activity in lichens

scholarly journals KARAKTERISTIK DAN SKRINING FITOKIMIA EKSTRAK ETANOL 70% BATANG KEPUH (Sterculia foetida L.)

Jurnal Kimia ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 22
Author(s):  
N. P. S. E. Cahyani ◽  
J. Susiarni ◽  
K. C.S. Dewi ◽  
N. L.P. Melyandari ◽  
K. W.A. Putra ◽  
...  
Keyword(s):  
Moisture Content ◽  
Water Content ◽  
Ethanol Extract ◽  
Phytochemical Screening ◽  
Residual Solvent ◽  
Solvent Content ◽  
Residual Content ◽  
Ethanol Level ◽  
Anti Inflammatory

Kepuh (Sterculia foetida L) is a type of kapok plant that has been scientifically proven to have activity as an anti-inflammatory and analgesic. 70% ethanol extract of stem stem is obtained by maceration using 70% ethanol. Examination of the characteristics of 70% ethanol extract of kepuh stem included organoleptic, of moisture content and determination of residual solvent content. Phytochemical screening of 70% ethanol extract of kepuh bark includes: alkaloid, flavonoid, saponin, tannin , polyphenol, and examination of glycosides. The results of the examination of the characteristics of 70% ethanol extract of kepuh stem obtained water content of 8.66 ± 0.748%, the residual content of the solvent had a 0 (zero) ethanol level. The results of phytochemical screening showed 70% ethanol extract of stem stem containing steroid compounds, triterpenoids, flavonoids, saponins, tannins and polyphenols. The identification using UV-Vis spectrophotometry produced ? 212, the absorbance was 1.8601 and ? 284, the absorbance was 0.42186.

The indirect determination of energy retention in farm animals: I. The development of method

1956 ◽  
Vol 48 (2) ◽  
pp. 194-209 ◽  
Author(s):  
K. L. Blaxter ◽  
J. A. F. Rook
Keyword(s):  
Water Content ◽  
Allantoic Fluid ◽  
The Body ◽  
Farm Animals ◽  
High Concentration ◽  
Adult Cattle ◽  
Indirect Determination ◽  
Energy Retention ◽  
The Relationship

1. Methods of estimating water retention in the body of cattle are discussed, and it is shown that methods based on determinations of the initial and final body-water content are of low accuracy and are not suitable for the indirect estimation of fat balance over a period of 24 days.2. Analyses of tissues from young and adult cattle showed that with the exception of serum, brain, skin and bone, water content of the tissues may be predicted from the following equation:Water(g./100g.) = 0·292 Na(mg./100g.) + 0·147 K(mg./100g.).This equation shows that 1 m.equiv. of the Na of tissues is associated with more water than is 1 m.equiv. of the K.3. No differences between cattle aged from less than 1 week to more than 5 years were observed in the relationship between water and Na and K content.4. The equation applied also to the contents of the digestive tract, other than those of the abomasum which gave low results, ascribed to the presence of a high concentration of H+ ions.5. Analyses of whole foetuses for Na, K and H2O showed that their water content could be predicted accurately. The same was true of amniotic fluid, but the water content of allantoic fluid was underestimated by 50%.6. It was shown that despite the anomalous behaviour of brain, serum, skin and bone, accurate predictions of the water content of the animal could be made from simultaneous determinations of Na and K retentions, providing a correction was made for the storage of bound Na in bone.7. Data are presented which indicate that the equations apply equally well to the tissues of the sheep.

Parameter Estimation for Evaluation of in Situ Density and Moisture Content by using Elastic and Electromagnetic Wave Propagation

2008 ◽  
Vol 2045 (1) ◽  
pp. 19-28 ◽  
Author(s):  
Bashar Alramahi ◽  
Dante Fratta ◽  
Khalid A. Alshibli
Keyword(s):  
Quality Control ◽  
Wave Propagation ◽  
Quality Assurance ◽  
Electromagnetic Wave ◽  
Moisture Content ◽  
Water Content ◽  
Electromagnetic Wave Propagation ◽  
Soil Density

Soil density and moisture content are two essential properties in the quality control and quality assurance of projects that involve soil compaction. However, current field practices either are destructive and time-consuming (i.e., sand cone or water balloon for soil density and oven drying for moisture content) or include hazardous substances that require special handling and operating procedures (i.e., nuclear density gauge). Therefore, new robust, reliable, and nonnuclear techniques for the determination of in situ density and moisture content would assist in quality control and quality assurance processes and would allow more measurements to be performed in a shorter time. A methodology for the in situ determination of density and moisture content by using the propagation of elastic and electromagnetic waves through soils was evaluated. It is based on a semiempirical model that relates elastic wave velocity through soils to the water content, porosity, and degree of saturation. An experimental program was used to verify the model and examine its range of applicability. It was also used to examine the accuracy and limitations of the suggested methodology. An analysis was made of the experimental assessment, along with a detailed numerical study of the inversion procedure used to calculate the density and moisture content. Although the parametric and experimental study shows that the methodology can provide an estimate of density and water content rapidly and non-destructively, there are inherent accuracy and precision limitations that need to be solved. These results also show that combined elastic and electromagnetic wave propagation measurements can help in the development of a methodology that may assist in solving inconsistencies in stiffness measurements.

scholarly journals Physicochemical Characteristics of Malaysian Stingless Bee Honey from Trigona Species

2018 ◽  
Vol 17 (1) ◽  
Author(s):  
Fatima IJ ◽  
Mohd Hilmi AB ◽  
Salwani I ◽  
Lavaniya M
Keyword(s):  
Electrical Conductivity ◽  
Moisture Content ◽  
Physicochemical Properties ◽  
Water Content ◽  
Physicochemical Characteristics ◽  
Ash Content ◽  
Stingless Bee ◽  
Apis Dorsata ◽  
Tualang Honey

The physicochemical properties of stingless bee honey are diverse according to origin of geographical or botanical and fruit or flower season. These factors result in production of honey with different colour, pH, ash and water content although the bee species is similar. To date, the physicochemical properties of honey from Malaysian Trigona species are unknown. Therefore, determination of physicochemical properties of honey from stingless bee is crucial for Malaysian researchers in order to analyse the purity of the honey. Five honey samples were used for the current study. Four samples were stingless bee honey from two of the most common domesticated Malaysian stingless bee species; Trigona thorasica and Trigona itama. Meanwhile, one sample was from Tualang honey. For stingless bee honey, the values for pH, moisture content, electrical conductivity, ash content and hydroxymethylfurfural (HMF) were 2.79±0.04 to 2.95±0.02, 28.3±0.68 to 33.7±0.51, 0.47±0.22 to 0.55±0.38, 0.132±0.03 to 0.532±0.83 and 0.080±0.16 to 3.42±1.03, respectively. The colour of stingless bee honey varies based on observation or absorbance assay. The study described the physicochemical properties derived from Malaysian bees of Trigona thorasica, Trigona itama, and Apis Dorsata.

scholarly journals POTENCIAIS HÍDRICOS E TEORES DE ÁGUA NA GERMINAÇÃO DE SEMENTES E CRESCIMENTO INICIAL DE MILHETO

2017 ◽  
Vol 15 (3) ◽  
pp. 619
Author(s):  
TATHIANA ELISA MASETTO ◽  
ELISÂNGELA LEITE VARGAS ◽  
SILVANA DE PAULA QUINTÃO SCALON
Keyword(s):  
Seed Germination ◽  
Moisture Content ◽  
Water Content ◽  
Pearl Millet ◽  
Pennisetum Glaucum ◽  
Dry Mass ◽  
Germination Percentage ◽  
Initial Growth ◽  
Water Potentials ◽  
Randomized Design

RESUMO – O processo germinativo se inicia com a absorção de água pelas sementes e é influenciado peladisponibilidade hídrica e pelo teor de água das sementes. Objetivou-se avaliar os efeitos de diferentes potenciais hídricose de teores de água das sementes na germinação e crescimento de plântulas de milheto. Foram utilizadas sementes comteores de água de 14,1%; 16,1%; 20,8% e 21,9% posicionadas em caixas plásticas do tipo “gerbox” sobre duas folhasde papel toalha para germinação previamente umedecidas com 10 mL de soluções de polietilenoglicol (PEG 6000) nospotenciais hídricos de 0,0; -0,1; -0,2; -0,3; -0,4 e -0,6 MPa. As sementes foram mantidas em câmara de germinação a25 °C sob luz branca constante. O delineamento experimental foi o inteiramente casualizado, em esquema fatorial 4x 5, utilizando-se quatro repetições de 50 sementes cada. As sementes foram avaliadas quanto à primeira contagem,germinação, comprimento da raiz, comprimento da parte aérea, comprimento total, massa fresca e seca de plântulas.A redução dos potenciais hídricos associada aos teores de água das sementes afeta negativamente a germinação e ocrescimento das plântulas de milheto, principalmente em sementes com o teor de água de 14,1%. As sementes com osteores de água acima de 16,1% são menos suscetíveis à redução das disponibilidades hídricas do substrato a partir dopotencial de -0,1 MPa.Palavras-chave: Pennisetum glaucum, polietilenoglicol, teor de água de sementes.WATER POTENTIAL AND MOISTURE CONTENT ON SEED GERMINATION AND INITIAL GROWTH OF PEARL MILLETABSTRACT – The germination process starts with water absorption by seeds and is influenced by the water availabilityand seeds moisture content. This work aimed to evaluate the effects of different substrate water potentials and the watercontents of the seeds on seed germination of pearl millet. The treatments comprised pearl millet seeds with 14.1%,16.1%, 20.8% and 21.9% moisture content and submitted to the water availability in the substrate of 0.0 (control); -0.1;-0.2; -0.3; -0.4 and -0.6 MPa. Seeds were sowed in two germination papers and positioned inside plastic boxes of the“gerbox” type and maintained at 25ºC. A completely randomized design in a factorial scheme 4 x 5 was used, with fourreplications of 50 seeds per treatment. The seeds were evaluated through the first counting, germination percentage,aerial part, root length, total length and fresh and dry mass of seedlings. The reduction of the water potentials associatedto the seed water contents affected negatively the seeds germination and seedlings growth of pearl millet, especially inseeds with 14.1% water content. The seeds with water content above 16.1% were less sensitive to the decrease in thewater availability of the substrate from -0.1 MPa.Keywords: Pennisetum glaucum, polyethylene glycol, seeds water content.

scholarly journals PEMBUATAN DEKSTRIN DARI PATI UBI KAYU MENGGUNAKAN ENZIM AMILASE DARI AZOSPIRILLUM sp. JG3 DAN KARAKTERISASINYA

Molekul ◽  
2010 ◽  
Vol 5 (1) ◽  
pp. 15 ◽  
Author(s):  
Dian Riana Ningsih ◽  
Ari Asnani ◽  
Amin Fatoni
Keyword(s):  
Moisture Content ◽  
Optimum Condition ◽  
Water Content ◽  
Substrate Concentration ◽  
Manihot Esculenta ◽  
Cassava Starch ◽  
Ash Content

Amylase enzyme is used to hydrolyze starch into simpler molecules such as dextrin. Amylase can be isolated fromAzospirillum sp. JG3 bacteria. The purpose of this study was to characterize dextrins from cassava starch (Manihot esculenta) is catalyzed by the enzyme amylase from Azospirillum sp. JG3 bacteria. Stages of this study are: determination of optimum substrat and to analyze the chemical and physical dextrins including moisture content, ash content, dexstrosa equivalent (DE) and the yield obtained. The result of this research showed that optimum condition hydrolysis starch of cassava that using amylase from Azospirillium sp. JG3 bacteria was acquired at substrate concentration 3% and the results of analysis obtained dextrins include yield of 96.67%, water content of 9.39%, 0.25% ash content and dexstrosa equivalent (DE) of 16.55.

POTENCIAIS HÍDRICOS E TEORES DE ÁGUA NA GERMINAÇÃO DE SEMENTES E CRESCIMENTO INICIAL DE MILHETO

2016 ◽  
Vol 15 (3) ◽  
pp. 619
Author(s):  
TATHIANA ELISA MASETTO ◽  
ELISÂNGELA LEITE VARGAS ◽  
SILVANA DE PAULA QUINTÃO SCALON
Keyword(s):  
Seed Germination ◽  
Moisture Content ◽  
Water Content ◽  
Pearl Millet ◽  
Water Availability ◽  
Pennisetum Glaucum ◽  
Germination Percentage ◽  
Initial Growth ◽  
Water Potentials ◽  
Water Contents

RESUMO – O processo germinativo se inicia com a absorção de água pelas sementes e é influenciado pela disponibilidade hídrica e pelo teor de água das sementes. Objetivou-se avaliar os efeitos de diferentes potenciais hídricos e de teores de água das sementes na germinação e crescimento de plântulas de milheto. Foram utilizadas sementes com teores de água de 14,1%; 16,1%; 20,8% e 21,9% posicionadas em caixas plásticas do tipo “gerbox” sobre duas folhas de papel toalha para germinação previamente umedecidas com 10 mL de soluções de polietilenoglicol (PEG 6000) nos potenciais hídricos de 0,0; -0,1; -0,2; -0,3; -0,4 e -0,6 MPa. As sementes foram mantidas em câmara de germinação a 25 °C sob luz branca constante. O delineamento experimental foi o inteiramente casualizado, em esquema fatorial 4 x 5, utilizando-se quatro repetições de 50 sementes cada. As sementes foram avaliadas quanto à primeira contagem, germinação, comprimento da raiz, comprimento da parte aérea, comprimento total, massa fresca e seca de plântulas. A redução dos potenciais hídricos associada aos teores de água das sementes afeta negativamente a germinação e o crescimento das plântulas de milheto, principalmente em sementes com o teor de água de 14,1%. As sementes com os teores de água acima de 16,1% são menos suscetíveis à redução das disponibilidades hídricas do substrato a partir do potencial de -0,1 MPa.Palavras-chave: Pennisetum glaucum, polietilenoglicol, teor de água de sementes.WATER POTENTIAL AND MOISTURE CONTENT ON SEED GERMINATION AND INITIAL GROWTH OF PEARL MILLETABSTRACT – The germination process starts with water absorption by seeds and is influenced by the water availability and seeds moisture content. This work aimed to evaluate the effects of different substrate water potentials and the water contents of the seeds on seed germination of pearl millet. The treatments comprised pearl millet seeds with 14.1%, 16.1%, 20.8% and 21.9% moisture content and submitted to the water availability in the substrate of 0.0 (control); -0.1; -0.2; -0.3; -0.4 and -0.6 MPa. Seeds were sowed in two germination papers and positioned inside plastic boxes of the “gerbox” type and maintained at 25ºC. A completely randomized design in a factorial scheme 4 x 5 was used, with four replications of 50 seeds per treatment. The seeds were evaluated through the first counting, germination percentage, aerial part, root length, total length and fresh and dry mass of seedlings. The reduction of the water potentials associated to the seed water contents affected negatively the seeds germination and seedlings growth of pearl millet, especially in seeds with 14.1% water content. The seeds with water content above 16.1% were less sensitive to the decrease in the water availability of the substrate from -0.1 MPa.Keywords: Pennisetum glaucum, polyethylene glycol, seeds water content.

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