Water Uptake Behavior of Lignin Modified Starch Film

2014 ◽  
Vol 699 ◽  
pp. 204-209 ◽  
Author(s):  
Ariyanti Sarwono ◽  
Zakaria Man ◽  
Mohd Azmi Bustam ◽  
Khairun Azizi Azizli
Keyword(s):  
Diffusion Coefficient ◽  
Water Uptake ◽  
Water Resistance ◽  
Second Law ◽  
Modified Starch ◽  
Distilled Water ◽  
Slab Model ◽  
Thin Slab ◽  
Different Temperatures ◽  
Calculated Diffusion Coefficient

A biodegradable urea crosslinked starch film was prepared. To improve the water resistance, the urea crosslinked starch system was reinforced with 5%, 10%, and 15% lignin. The prepared films were immersed in distilled water at three different temperatures, 25°C, 35°C and 45°C to study the behavior of water uptake. The addition of lignin effectively decreases water uptake as proven by lower water uptake equilibrium. Diffusion coefficient was calculated from the kinetic water uptake profile using the slope method of Fick’s second law for thin slab model. The calculated diffusion coefficient decreases as the lignin is increased. The diffusion coefficient is found to be dependent on the temperature. As more lignin is added to the system, higher activation energy is obtained due to the hydrophobicity of lignin.

Influence de la température et de la durée d'un traitement cryoprotecteur sur la résistance au froid de plantules de blé. Étude ultrastructurale des ébauches foliaires

1983 ◽  
Vol 61 (4) ◽  
pp. 1025-1039 ◽  
Author(s):  
C. M. Gazeau
Keyword(s):  
Endoplasmic Reticulum ◽  
Treatment Period ◽  
Day Treatment ◽  
Leaf Primordia ◽  
Ultrastructural Changes ◽  
Distilled Water ◽  
Wheat Seedlings ◽  
Starch Grains ◽  
Different Temperatures ◽  
Protective Treatment

Wheat seedlings were treated at different temperatures and for various periods of time with a cold-protective substance, composed of a mixture of glycerol, dimethylsulfoxide, and saccharose. When the treatment was done at 20 °C, slight ultrastructural changes appeared in leaf primordia as soon as day 1. Thus numbers of lipid globules increased significantly. When the treatment period was increased to 4 days, numbers of starch grains increased, and there was a marked enlargement of mitochondria and plasts. When the treatment was done at 2 °C, cytoplasmic alterations occurred later than at 20 °C. After a 4-day treatment, they were similar to changes induced at 20 °C. When the treatment period was increased to 12 days, dictyosomes were markedly altered. They clustered close to the nucleus in two or three groups and gave rise to numerous pale vesicles with various shapes and sizes. Around each cluster of such vesicles, there gathered many endoplasmic reticulum vesicles and other organelles (mitochondria, plasts, microbodies, vacuoles). A further cooling of 1 °C/min, down to −15 or −30 °C, enhanced these phenomena. After the seedlings were warmed up to 20 °C in distilled water, the changes induced by the frost-protective treatment and then by freezing were shown to be reversible. [Journal translation]

scholarly journals The effect of temperature change on fluoride uptake from a mouthrinse by enamel specimens

2012 ◽  
Vol 06 (04) ◽  
pp. 361-369 ◽  
Author(s):  
Serdar Baglar ◽  
Adil Nalcaci ◽  
Mustafa Tastekin
Keyword(s):  
Body Temperature ◽  
Room Temperature ◽  
Hot Water ◽  
Effect Of Temperature ◽  
Distilled Water ◽  
Fluoride Solution ◽  
Fluoride Uptake ◽  
Significant Difference ◽  
Human Body Temperature ◽  
Different Temperatures

ABSTRACTObjective: The aim of this study was to examine the effect of temperature on fluoride uptake by enamel specimens from a 0.05% NaF-fluoridated mouthrinse (Oral-B Advantage; Oral-B Laboratories, Newbridge, UK).Methods: Enamel specimens were prepared from extracted human maxillary central incisors. A fluoride-specific ion electrode was used to measure the uptake from a 2 ppm fluoride solution containing 50.0 mL of distilled water, total ion strength adjustment buffer, and fluoridated rinse at 3 different temperatures (room temperature, 25°C; human body temperature, 37°C; hyper-fever temperature, 43°C). One-way analysis of variance and least significant difference were used to assess intragroup and intergroup differences (P<.05).Results: The study found that both the amount and the rate of fluoride uptake increased significantly with increase in temperature. This effect was particularly noticeable at 43°C.Conclusions: The temperature of the NaF mouthrinse may easily and safely be increased beyond room temperature by placing a container of the NaF mouthrinse in a bowl of hot water, allowing greater fluoride penetration into the enamel from the mouthrinse when used at home as a routine prophylactic agent. (Eur J Dent 2012;6:361-369)

scholarly journals The rainfall effect onto solidification and stabilization of heavy metal-polluted sediments

2020 ◽  
Vol 7 (7) ◽  
pp. 192234
Author(s):  
Yan Sun ◽  
Daofang Zhang ◽  
Feipeng Li ◽  
Hong Tao ◽  
Moting Li ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Diffusion Coefficient ◽  
Simulated Acid Rain ◽  
Curing Process ◽  
Deterioration Rate ◽  
Before And After ◽  
Calculated Diffusion Coefficient ◽  
Leaching Procedure

Rainfall makes impacts on the process of solidification/stabilization (S/S) and the long-term safety of solidified matrix. In this study, the effect of rainfall on solidification/stabilization process was investigated by the rainfall test. The unconfined compressive strength (UCS) and toxicity characteristic leaching procedure (TCLP) were adopted to characterize the properties of S/S sediments before and after the rainfall test. The samples cured for 28 days were selected for semi-dynamic leaching tests with a simulated acidic leachant prepared at pH of 2.0, 4.0 and 7.0. The effectiveness of S/S treatment was evaluated by diffusion coefficient ( D e ) and leachability index (LX). The results indicated that UCS decreased at maximum deterioration rate of 34.23% after 7 days of curing, along with the minimum rate of 7.98% after 28 days by rainfall, with greater than 14 days referred. The rainfall had little effect on the leaching characteristics of heavy metals during the curing process. However, the simulated acid rain made significant impacts on the leaching behaviours of the heavy metals in the S/S materials. All the values of cumulative fraction of leached heavy metals were less than 2.0%, exhibition of good stabilization of cement. Furthermore, the calculated diffusion coefficient ( D e ) for Cu was 1.28 × 10 1 cm 2 s –1 , indicating its low mobility of heavy metal ions in S/S sediments. Furthermore, the calculated diffusion coefficients ( D i ) for Cd, Cu and Pb were 7.44 × 10 −11 , 8.18 × 10 −12 and 7.85 × 10 −12 cm 2 s –1 , respectively, indicating their relatively low mobility of heavy metal in S/S sediments.

Diffusion und Korrelation in goldreichen Gold—Zinn-Mischkristallen / Diffusion and Correlation in Gold-Rich Gold—Tin Solid Solutions

1972 ◽  
Vol 27 (7) ◽  
pp. 1109-1118 ◽  
Author(s):  
Chr. Herzig ◽  
Th. Heumann
Keyword(s):  
Diffusion Coefficient ◽  
Impurity Content ◽  
Chemical Diffusion ◽  
Correlation Factor ◽  
Coarse Grained ◽  
Pure Gold ◽  
Large Temperature ◽  
Chemical Diffusion Coefficient ◽  
Self Diffusion ◽  
Different Temperatures

Abstract The diffusion of Sn-113 and Au-195 in pure gold and dilute tin -gold alloys has been measured at different temperatures and tin concentrations in coarse-grained specimens. In addition the dependence on concentration of the chemical diffusion coefficient and the diffusion of tin in gold at very low impurity concentrations has been determined using the electron microprobe. It was found, that the self-diffusion coefficient of tin as well as that of gold increased strongly with in-creasing impurity content. The thermodynamic factor is equal to one up to ca. 0.5 at.-% tin. For the correlation factor of the diffusion of tin in gold, calculated by the relation of Lidiard, an essentially temperature independent value is obtained. A comparison of the experimental results with the model of Le Claire concerning the impurity diffusion in metals shows, that this model seems to require a too-large temperature dependence of the correlation factor

scholarly journals Priming and temperature limits for germination of dispersal units of Urochloa brizantha (Stapf) Webster cv. basilisk

2015 ◽  
Vol 75 (1) ◽  
pp. 234-241
Author(s):  
EA. Nakao ◽  
VJM. Cardoso
Keyword(s):  
Priming Effect ◽  
Base Temperature ◽  
Distilled Water ◽  
Optimum Temperature ◽  
Thermal Limits ◽  
Ceiling Temperature ◽  
Germination Temperature ◽  
Different Temperatures ◽  
Urochloa Brizantha ◽  
Potential Conditions

The objective of this study was to evaluate the effect of priming treatments on the upper and lower thermal limits for germination of Urochloa brizantha cv. basilisk, and testing the hypothesis that pré-imbibition affect thermal parameters of the germination. Pre-imbibed seeds both in distilled water (0 MPa) and PEG 6000 solution (–0.5 MPa) were put to germinate in different temperatures. It is suggested that U. brizantha seeds have low response to priming when they were placed to germinate in medium where water is not limiting. The response of U. brizantha seeds to priming is dependent on the temperature and water potential conditions at which the seeds are pre-imbibed, as well as on the germination temperature. The optimum temperature for germination of U. brizantha shift toward warmer temperatures in primed seeds. Priming effect was more pronounced at temperatures closer to the upper and lower limit for germination, but probably that response cannot be accounted for changes in the thermal time constant (θT(g)) and ceiling temperature (Tc(g)). Otherwise, a decrease in the base temperature (Tb) was observed in primed seeds, suggesting that the Tb distribution in U. brizantha seeds is influenced by priming.

scholarly journals Water uptake by Annona diversifolia Saff. and A. purpurea Moc. & sessé ex dunal seeds (Annonaceae)

2014 ◽  
Vol 36 (spe1) ◽  
pp. 288-295 ◽  
Author(s):  
Gisela Ferreira ◽  
Alma Rosa González Esquinca ◽  
Ivan De-La-Cruz-Chacón
Keyword(s):  
Phase I ◽  
Water Uptake ◽  
Phase Iii ◽  
Distilled Water ◽  
Physiological Dormancy

Annonaceae seeds are known by presenting dormancy mechanisms, whose reports ranging from coating impermeable to the physiological dormancy. By this way, the present study aimed to evaluate water uptake in Annona diversifolia Saff and Annona purpurea Moc & Sessé ex Dunal seeds. For this study, seeds were placed under immersion in distilled water, and used four replicates of 25 seeds of each species, which were weighed during the 480 hours that were immersed. To determine the place of purchase of water, Annona diversifolia seeds were sealed with paraffin at different locations. Based on the results, seeds from both species reached the phases I and II of water uptake, which indicates they are not hard; however, germination (Phase III) was not reached. Annona diversifolia seeds completed Phase I with, 50h and Annona purpurea with 70h from imbibitions begin, which shows that even slowly, water is acquire.

Imbibitional chilling injury in cultivars of soybeans differing in temperature sensitivity to pod formation and maturation periods

1983 ◽  
Vol 61 (12) ◽  
pp. 2996-2998 ◽  
Author(s):  
Winson Orr ◽  
A. I. De La Roche ◽  
J. Singh ◽  
H. Voldeng
Keyword(s):  
Water Uptake ◽  
Seed Set ◽  
Chilling Injury ◽  
Controlled Environment ◽  
Early Maturing ◽  
Different Temperatures ◽  
Glycine Max L ◽  
Filter Papers ◽  
Environmental Temperatures ◽  
Irreversible Injury

The occurrence and extent of chilling injury during imbibition of seeds from five cultivars and four lines of soybeans (Glycine max (L.) Merr) were tested. Seeds were imbibed and incubated at 2 °C for up to 72 h on moist filter papers and their ability to germinate when returned to 25 °C was recorded. Early-maturing varieties with the ability to form pods and seeds at lower temperatures were most susceptible to irreversible injury during imbibitional chilling. Rate of water uptake during low-temperature imbibition was measured, and seeds which were most susceptible to imbibitional chilling also had the highest rate of water uptake. In controlled-environment studies, seeds from the same cultivars that were set at different temperatures showed corresponding differences in susceptibility to imbibitional chilling injury. These results suggest that environmental temperatures during seed set or pod formation can play a role in chilling tolerance during seed imbibition.

Interdiffusion in Nb-Mo, Nb-Ti and Nb-Zr Systems

2012 ◽  
Vol 323-325 ◽  
pp. 491-496 ◽  
Author(s):  
Soma Prasad ◽  
Aloke Paul
Keyword(s):  
Activation Energy ◽  
Diffusion Coefficient ◽  
Diffusion Couple ◽  
Impurity Diffusion ◽  
Impurity Diffusion Coefficient ◽  
Different Temperatures ◽  
Diffusion Couple Technique ◽  
Interdiffusion Coefficients

Diffusion couple technique is used to study interdiffusion in Nb-Mo, Nb-Ti and Nb-Zr systems. Interdiffusion coefficients at different temperatures and compositions are determined using the relation developed by Wagner. The change in activation energy for interdiffusion with composition is determined. Further, impurity diffusion coefficient of the species are determined and compared with the available data in literature.

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