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The thermal treatment of wood changes its structure due to the degradation of wood polymers (cellulose, hemicellulose and lignin), so the physical properties of wood are either improved or degraded. Color changes apply not only to natural wood, but also to such wood composites for which some amount of glue is used in their construction (e.g., plywood, blockboard or laminboard). This article is focused on the analysis of hornbeam and field maple wood color changes influenced by drying temperature. Two types of drying modes were used: hot-air mode where the temperature of the drying environment was 60 °C, and high-temperature mode with a drying temperature of 120 °C. The drying mode was divided into two phases depending on the moisture content of the wood. The compared woods had similar values of color coordinates at the beginning of drying. During hot-air drying, the largest changes in color coordinates occurred during the first 24 h. The total color difference between the color at the end and the beginning of drying was 7.3 for hornbeam and 11.1 for maple. The overall color difference between the compared woods was minimal. During high-temperature drying (120 °C), the color changes of the dried woods were more pronounced. In the case of maple wood, there was a very significant change in color and the value of ΔE* was twice as high as for hornbeam. The total color difference between the color at the end and at the beginning of drying was 8.7 for hornbeam and 18.9 for maple.

The article presents an experimental study of mechanical properties of cellulose biofilm produced by bacterial fermentation process. Naturally derived biomaterial has great current and potential applications therefore the conditions of material preparation as well as control and prediction of mechanical properties is still a relevant issue. Bacterial cellulose was obtained as a secondary product from Kombucha drink. Presented technique for material preparation and drying is particularly simple and easy to access. The influence of drying temperature (25 °C, 50 °C and 75 °C) on the sample size (thickness and planar dimensions) and mechanical properties (tensile and bursting strength) of cellulose biofilm has been evaluated. It was estimated that during drying biofilm specimens lost up to 92 % of weight and up to 87 % of thickness therefore planar specimen dimensions varied insignificantly. The study showed that the drying temperature is important for optimum strength properties of bacterial cellulose biofilm. The maximum tensile strength (27.91 MPa) was recorded for the samples dried at temperature of 25 °C, when the moisture from the biomaterial is removed gradually and good deformation properties are ensured (respectively tensile extension 18.8 %). Under higher drying temperature biomaterial shows lower values of tensile strength and higher values of bursting strength. The maximum bursting strength (57.2 MPa) was recorded for samples dried at 75 °C when punch displacement changes were insignificant for all tested samples (from 17.8 mm to 21.7 mm). DOI: http://dx.doi.org/10.5755/j01.ms.25.3.20764

Kraft lignin, an industrially available by-product from the pulp and paper industry, has revealed enormous potential to be valorised into a wide range of chemicals and biomaterials in the last two decades. However, the understanding of lignin chemistry remains challenging due to its chemical complexity. The goal of this work was to investigate the effect of drying temperature on the chemical, physical, and hygroscopic properties of hardwood kraft lignin isolated from industrial black liquor and elucidate the molecular interactions occurring between water and kraft lignin. Sorption-desorption isotherms determined by dynamic vapour sorption (DVS) technique revealed that the drying process considerably affected the hygroscopicity of the lignin polymer. Moreover, analytical pyrolysis (Py–GC–MS), dynamic NIR spectra collected as a function of relative humidity (0–95%) during sorption-desorption cycles and principal component analysis (PCA), evidenced chemical differences between lignin dried at room (25°C) temperature and mild oven (55°C) conditions. The main spectral changes associated with the water sorption in kraft lignin samples were analyzed using difference spectrum technique. 2D NIR spectral correlation analysis provided water sorption mechanism of lignin polymer, disclosing for the first time the sequential order in which water vapour molecules interact with active sorption sites in kraft lignin.

Watermelon is a valuable source of nutrients and antioxidants that are beneficial for human health, but it is a seasonal and easily perishable fruit. Appropriate drying conditions should be considered to maintain the quality and nutritional attributes of watermelons after hot-air drying. This study aimed to investigate the effect of drying temperature and air velocity on some quality characteristics by response surface methodology. The drying trials were performed at temperatures of 55, 65, and 75 degrees C and air velocity of 1, 1.5, and 2 m/s employing a face-centered composite design. Some physical (a* value and browning index) and chemical (total polyphenols, the ferric reducing/antioxidant power, total anthocyanin, ascorbic acid, sucrose, total sugar, lycopene, total carotenoid, 5-HMF, and non-enzymatic browning) properties of dried watermelons were determined. The results indicated that the effect of drying temperature on the analyzed attributes was more significant than air velocity in general. Polynomial models with high R-2 values were generated to predict the responses. The optimum drying conditions obtained (65.425 degrees C and 1.025 m/s) were experimentally validated. The proposed conditions provided better preservation of the quality characteristics (physical and chemical) studied for the commercialization of dried watermelons as a snack.

Sunflower seed storage is accompanied by the loss of seed vigor. Seed drying is a key link between seed harvest and seed storage; however, to date, the effect of seed drying on sunflower seed deterioration during storage remains unclear. The present study performed hot air drying for sunflower seeds with an initial moisture content of 30% to examine the manner in which drying temperature (35, 40, 45, 50, and 55°C) affects the drying performance and seed vigor following storage process (6 and 12 months). A drying temperature of 40°C was evidently safe for sunflower seeds, whereas the high drying temperatures (HTD, 45, 50, and 55°C) significantly lowered sunflower seed vigor by regulating the fatty acid metabolism, glycometabolism, and abscisic acid (ABA)/gibberellin (GA) balance. HDT significantly increased the seed damage rate and accelerated sunflower seed deterioration during natural and artificial aging process. Further biochemical analysis indicated that HDT significantly increased lipoxygenase and dioxygenase activities, leading to malonaldehyde and reactive oxygen species over-accumulation during storage. During early seed germination, HDT significantly inhibited fatty acid hydrolysis and glycometabolism by decreasing triacylglycerol lipase, CoA-SH oxidase, and invertase activities. Moreover, HDT remarkably increased ABA levels but reduced GA levels by regulating gene expressions and metabolic enzyme activities during early imbibitions. Cumulatively, the seed drying effect on sunflower seed vigor deterioration during the storage process may be strongly related to fatty acid oxidation and hydrolysis metabolism, toxic substance accumulation, and ABA/GA balance.

Broiler live performance may be influenced by postharvest corn drying temperature, and results could depend on particle size after grinding. The supplementation with an exogenous amylase may improve performance parameters, but responses to enzymes are also affected by particle size. Two parallel experiments were conducted to evaluate the effects of hard-kernel corn dried at 2 temperatures (35°C and 120°C), ground at 2 particle sizes (coarse or fine), and 3 supplementation levels (0, 133, and 266 g ton-1) of an exogenous amylase on live performance, gastrointestinal organ development, energy utilization, and nutrient digestibility. Twelve dietary treatments resulting from a 2 × 2 × 3 factorial arrangement of drying temperature, particle size, and amylase supplementation were evaluated in both experiments. A total of 1,920 day-old male chicks were randomly allocated to 96 floor pens, while 480 chicks were distributed among 4 battery brooder units. Ileal and fecal samples were collected to determine energy utilization and nutrient digestibility using titanium dioxide as inert marker. At 42 D, organs were collected, and relative weight or length was determined. Data were analyzed using a three-way ANOVA in a randomized complete block design. Feeding fine corn-based diets showed improvements on live performance for both studies. At 40 D, supplementing 266 g ton-1 of amylase improved feed conversion ratio (P < 0.05) by 1 point compared to chickens that consumed nonsupplemented diets and feed with amylase at 133 g ton-1. Broilers fed coarse corn-based diets had heavier gizzard (P < 0.001) and liver (P < 0.05) than chickens that consumed fine corn-based diets. In addition, starch digestibility was improved by amylase (P < 0.05) at 133 g ton-1 and by feeding coarse corn-based diets (P = 0.06). For chicks raised in cages (16 D), AMEn was increased (P < 0.01) by amylase supplementation regardless of its inclusion level. In conclusion, drying temperature and particle size interactions influenced broiler live performance, gastrointestinal organ development, nutrient digestibility, and energy utilization, and these parameters were improved by supplementing amylase.

Drying temperature (DT) of corn can influence its nutritional quality, but whether this is influenced by endosperm hardness is not clear. Two parallel experiments were conducted to investigate the effects of 2 yellow dent corn hybrids with average and hard kernel hardness, dried at 3 temperatures (35, 80, and 120°C), and 2 supplementation levels of an exogenous amylase (0, 133 g/ton of feed) on live performance, starch and protein digestibility, and energy utilization of Ross 708 male broilers. Twelve dietary treatments consisting of a 2 × 3 × 2 factorial arrangement were evaluated using 3-way ANOVA in a randomized complete block design. In Experiment 1, a total of 1,920 male-chicks were randomly allocated to 96 floor pens, whereas 480 day-old chicks were distributed among 96 cages for Experiment 2. At 40 d, interaction effects (P < 0.05) were detected on BWG, FCR, and flock uniformity. Supplementation with exogenous amylase resulted in heavier broilers, better FCR and flock uniformity, only in the diets based on corn dried at 35°C. Additionally, interaction effects were observed on FCR due to kernel hardness and DT (P < 0.01), kernel hardness and amylase supplementation (P < 0.001), and DT and amylase supplementation (P < 0.05). Exogenous amylase addition to the diets based on corn with an average hardness improved FCR up to 2 points (1.49 vs. 1.51 g:g) whereas there was no effect of amylase on FCR of broilers fed diets based on corn with hard endosperm. Total tract retention of starch was increased (P < 0.05) in broilers fed diets based on corn with average kernel hardness compared to hard kernel. Corn dried at 80 and 120°C had up to 1.21% points less starch total tract retention than the one dried at 35°C. Supplementing alpha-amylase resulted in beneficial effects for broiler live performance, energy utilization, and starch total tract digestibility results. Treatment effects on starch characteristics were explored. Corn endosperm hardness, DT and exogenous amylase can influence the live performance of broilers. However, these factors are not independent and so must be manipulated strategically to improve broiler performance.

The effect of drying temperature on total anthocyanin and moisture contents in purple waxy corn kernel was investigated by using a tunnel dryer. The amount of anthocyanin and moisture content were studied with the relatively low drying temperature of 60–80 °C under controlling air velocity at 1.5 m/s. The experimental results reveal that moisture content in purple waxy corn kernel slightly decreases with time and the lowest moisture content obtained by using the present method is 13%wb (wet basis). The drying rate increases with increasing temperature and the highest rate is obtained at the temperature of 80 °C (0.1492% min−1). Total anthocyanin content in purple waxy corn kernel was strongly affected by the drying temperature and moisture content. The highest total anthocyanin content was obtained at the temperature of 65 °C with the moisture content of 13%wb, which is the best condition for preserving purple waxy corn kernel by using a tunnel dryer.

Chitosan (CHT) is a polysaccharide with multiple claimed properties and outstanding biocompatibility, generally attributed to the presence of protonable amino groups rendering a cationic natural polymer. However, the effect of changes in CHT structure due to hydration is not considered in its performance. This study compares the effects on biocompatibility after drying at 25 &deg, C and 150 &deg, C scaffolds of chitosan, polyethylene glycol diglycidyl ether (PEGDE) crosslinked CHT (low, medium and high concentration) and glutaraldehyde (GA) crosslinked CHT. PEGDE crosslinked CHT showed a reduction in free amino groups and the amide I/II ratio, which exhaustive drying reduced further. In X-ray diffraction (DRX) analysis, PEGDE crosslinked CHT showed multiple peaks, whereas the crystallinity percentage was reduced with an increase in PEGDE concentration and thermal treatments at 150 &deg, C. In a direct contact cell assay, high osteoblast viability was achieved at low and medium PEDGE concentrations, which was improved when the crosslinked scaffolds were thermally treated at 150 &deg, C. This was attributed to its partial hydrophilicity, low crystallinity and low surface roughness, this in spite of the small reduction in the amount of free amino groups on the surface induced during drying at 150 &deg, C. Furthermore, PEGDE crosslinked CHT scaffolds showed strong vinculin and integrin 1&beta, expression, which render them suitable for bone contact applications.

International audience; This work investigates the effect of relative humidity (RH) and temperature on drying phenomenon of a siloxane coating during the sol-gel process. An experimental approach was taken, due to a lack of available data in existing literature. Dynamic Vapor Sorption, Fourier Transform Infra-Red spectroscopy and X-ray Photoelectron Spectroscopy analyses were performed during sol drying, while controlling RH and temperature. The drying time increased exponentially when RH was increased. This was linked to water uptake and evaporation rate decrease, forming a more condensed coating. The thermally activated process was fitted by the Arrhenius law with an activation energy of 41.7 kJ mol−1. A double exponential law was proposed to describe the time needed for drying the sol as a function of temperature and RH. Finally, differences in the gel formed were clearly demonstrated. Between a RH of 30 and 50%, the gel formation turned from a dry-before-gel to a gel-before-dry phenomenon, stressing the importance of temperature and RH control during the drying process of the sol.

The influence of drying temperature on the starch crystallites and its impact on durum wheat pasta sensory properties is addressed in this work. In particular, spaghetti were produced by means of a pilot plant using 5 different drying temperature profiles. The sensory properties, as well as the cooking quality of pasta were assessed. X-ray powder diffraction was used for investigating changes in the crystallinity content of the samples. Starch crystallinity, size and density of the starch crystallites were determined from the analysis of the diffraction profiles. As expected, spaghetti sensory properties improved as the drying temperatures increased. In particular, attributes as resistance to break for uncooked samples and firmness, elasticity, bulkiness and stickiness for cooked samples, all benefit from drying temperature increase. The spaghetti cooking quality was also positively affected by the drying temperature increase. Diffraction analysis suggested that the improvement of sensory properties and cooking quality of pasta were directly related to the increase in density of both physical crosslink of starch granules and chemical crosslink of protein matrix. (C) 2016 Elsevier Ltd. All rights reserved.

In this study, whole and peeled persimmons were dried in the ranges of 55–75 °C of drying temperature in a hot air dryer. The effect of drying temperature and pretreatments on the drying characteristics was determined. Immersing in a solution of 20 % sucrose resulted in an increase in the drying rate of persimmons. A non-linear regression procedure was used to fit five thin-layer drying models available in the literature to the experimental moisture loss data. The Page and Modified Page models have shown a better fit to the experimental drying data as compared to other models. The effective diffusivity was determined to be 9.237 × 10−10–10.395 × 10−10 m2 s−1 for the blanched persimmons and 7.755 × 10−10–9.631 × 10−10 m2 s−1 for immersed sucrose solution persimmons. The activation energies for diffusion were calculated to be 56.09 kJ mol−1 (for blanched) and 10.28 kJ mol−1 (for immersed sucrose solution). © 2016, Springer-Verlag Berlin Heidelberg.

This study was performed to evaluate the antioxidant activity of oven-dried tomato powder (OTP) as affected by drying temperature and the effect of OTP on the product quality of pork patties. Three OTP products were obtained by drying of fresh tomato at 60, 80 and 100℃ oven until constant weight was obtained. Total phenolic content of three kinds of OTPs ranged from 1.95 to 5.94 g/100 g. The highest amount of total phenolic compound was observed in OTP dried at 100℃. Antioxidant activity of three kinds of OTPs was measured by 1,1-diphenyl-2-pycrylhydrazyl (DPPH)-radical scavenging activity, iron chelating ability, reducing power and measurement of lipid peroxide in linoleic acid emulsion system. In all parameters, OTP at 100℃ showed the higher antioxidant activity than other temperatures (p0.05). Therefore, OTPs could be used as a natural antioxidant in meat products.

In an effort to understand the effects of H2O activity on zeolite formation, we have synthesized LTA zeolite using a combination of freezing processes and varying drying temperatures. Sodium aluminate and sodium silicate were used to form LTA zeolite, according to the IZA (International Zeolite Association) protocol. The synthesis steps were modified by adding the precursor frozen process by a rapid liquid nitrogen (&minus, 196 &deg, C) treatment or slow conventional freezer treatment (&minus, 20 &deg, C). The samples were subsequently sonicated and then dried at 80 &deg, C or 40 &deg, C. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were performed on the samples immediately after the drying process as well as after 2 weeks and 1 month of aging the solid products. The results indicated that LTA zeolite does not form. The silica-alumina precursor after both freezing processes and after being dried at 80 &deg, C showed the presence of sodalite displaying stable behavior over time. Both sets of samples dried at 40 &deg, C and did not show the presence of zeolite immediately after the drying process. However, after 2 weeks, the liquid nitrogen&ndash, frozen precursor was characterized by the presence of EMT whereas zeolites never formed in the &minus, C samples. These results suggest that freezing processes differently control the H2O activity during the drying and aging processes in the solid state. Thus, although the precursor chemical composition is the same, the type of zeolite formed is different.

The essential oil of basil (Ocimum basilicum) has significant biological activity against insect pests and can be extracted through various techniques. This work aimed to optimize and validate the extraction process of the essential oil of O. basilicum submitted to different drying temperatures of the leaves and extracted by the combination of a Clevenger method and ultrasound. The biological activity of the extracted oil under different conditions was evaluated for potential control of Sitophilus zeamais. The extraction method was optimized according to the sonication time by ultrasound (0, 8, 19, 31 and 38 min) and hydrodistillation (20, 30, 45, 60 and 70 min) and drying temperature (20, 30, 45, 60 and 70 &deg, C). The bioactivity of the essential oil was assessed against adults of S. zeamais and the effects of each variable and its interactions on the mortality of the insects were evaluated. The best yield of essential oil was obtained with the longest sonication and hydrodistillation times and the lowest drying temperature of leaves. Higher toxicity of the essential oil against S. zeamais was obtained by the use of ultrasound for its extraction. The identification and the relative percentage of the compounds of the essential oil were performed with a gas chromatograph coupled to a mass selective detector. The performance of the method was assessed by studying selectivity, linearity, limits of detection (LOD) and quantification (LOQ), precision and accuracy. The LOD and LOQ values for linalool were 2.19 and 6.62 &micro, g mL&minus, 1 and for estragole 2.001 and 6.063 &micro, 1, respectively. The coefficients of determination (R2) were &gt, 0.99. The average recoveries ranged between 71 and 106%, with coefficient of variation &le, 6.4%.

Degradation kinetics of lycopene, ß-carotene and ascorbic acid in tomato quarters of Rio Grande variety were determined during hot air drying. Tomato quarters were dried at five different temperatures (60, 70, 80, 90 and 100 °C) in a cabinet drier at an airflow rate of 0.2 m/s and 20% relative humidity. Degradation kinetics of lycopene, ß-carotene and ascorbic acid in tomato quarters during hot air drying followed a first-order reaction. Drying temperature had a significant influence on the loss of lycopene, ß-carotene and ascorbic acid in tomato quarters. The range of the reaction rate constants for lycopene, ß-carotene and ascorbic acid losses were 0.078-0.448, 0.084-0.38, and 0.076-0.472 h -1, respectively. Activation energy calculated for lycopene and ascorbic acid was about 47 kJ/mol, and 40 kJ/mol for ß-carotene. The most effective temperature change in tomatoes was from 70 to 80 °C for lycopene and ß-carotene degradation, while it was from 60 to 70 °C for ascorbic acid degradation. © 2012 Elsevier Ltd.

Background Tripterygium wilfordii Radix, a well-known traditional medicine in china which is used for treatment of inflammation, pain, tumor and immune regulation for centuries in china, accompany with the serious toxic side effects. This study was carried out for simultaneously analyzing the four main components (triptolide, triptophenolide, demethylzeylasteral and celastrol) in Tripterygium wilfordii Radix under different drying processes, which was important for reducing the toxicity and quality control of Tripterygium wilfordii Radix in future. Methods The terpenes were extracted by using ultrasonic method with ethyl acetate from root or cortex of Tripterygium wilfordii Radix, and the sensitive and rapid HPLC-PDA method was developed for simultaneous quantification of triptolide, triptophenolide, demethylzeylasteral and celastrol in root and cortex of Tripterygium wilfordii Radix for evaluation of the impacts by different drying processes. Results The four compounds in their respective determined arrange had good linearity of 0.9998≦R2≦0.9999 and the average recoveries were range from 94.69 to 100.28%, RSDs were within 0.27 to 2.42%, respectively. The contents of triptolide, triptophenolide, demethylzeylasteral and celastrol in different Tripterygium wilfordii Radix individuals were varied greatly at different drying temperatures. Under different temperatures, the contents of triptolide, triptophenolide, demethylzeylasteral, and celastrol were 37.94–70.31 mg/g, 0–1.807 mg/g, 0.3513–9.205 mg/g, 3.202–15.31 mg/g, respectively. The suitable drying temperature of terpenoids in root of wild and cultivate are 80 °C and 60 °C, the suitable drying temperature of terpenoids in cortex is 40 °C. Conclusions The method established is high sensitivity, accuracy, reliability and suitable for the simultaneous analysis of terpenoids in Tripterygium wilfordii Radix. The data provide a scientific basis and reference for the quality control of herb and preparations related to Tripterygium wilfordii Radix.

The hopcalite (CuMnO x ) catalyst is a well-known catalyst for oxidation of CO at ambient temperature. It has prepared by co-precipitation method and the preparation parameters were like Copper/Manganese (Cu:Mn) molar ratios, drying temperature, drying time, calcination temperature and calcination time has an influence on activity of the resultant catalyst. The activity of the catalyst was measured in flowing air calcinations (FAC) conditions. The reaction temperature was increased from ambient to a higher value at which complete oxidation of CO was achieved. The particle size, weight of catalyst and CO flow rate in the air were also influenced by the activity of the catalyst for CO oxidation. The characterizations of the catalysts were done by several techniques like XRD, FTIR, BET, SEM-EDX and XPS. These results were interpreted in terms of the structure of the active catalyst. The main aim of this paper was to identify the optimum preparation conditions of CuMnO x catalyst with respect to the performance of catalyst for CO oxidation. Copyright © 2017 BCREC Group. All rights reserved Received: 9 th January 2017; Revised: 24 th May 2017; Accepted: 25 th May 2017 ; Available online: 27 th October 2017; Published regularly : December 2017 How to Cite : Dey, S., Dhal, G.C., Mohan, D., Prasad, R. (2017). Effect of Preparation Conditions on the Catalytic Activity of CuMnO x Catalysts for CO Oxidation. Bulletin of Chemical Reaction Engineering & Catalysis , 12 (3): 431-451 (doi:10.9767/bcrec.12.3.900.437-451)

Cellulose nanofibrils (CNF) were spun into filaments directly from suspension without the aid of solvents. The influence of starting material properties and drying temperature on the properties of filaments produced from three different CNF suspensions was studied. Refiner-produced CNF was ground using a microgrinder at grinding times of 50 and 100 minutes. Filament spinning was performed using a syringe pump-heat gun setting at three drying temperatures of 210 °C, 320 °C and 430 °C. The structure of starting CNF materials was first evaluated using a combination of optical and atomic force microscopy (AFM) techniques. Surface free energy analysis and attenuated total reflectance—Fourier transform infrared spectroscopy (ATR–FTIR) were used to study changes in hydrophobicity due to grinding. Morphology of the filaments was studied using SEM micrographs. The influence of different drying temperatures and grinding times on mechanical properties of the CNF filaments were further investigated through tensile tests and results were compared using statistical analysis .It was observed that drying temperature did not significantly influence the tensile properties of the filaments while cellulose nanofiber suspension type (grinding time) had a significant influence and improved mechanical properties. FTIR results confirmed an increase in crystallinity index and decrease in hydroxyl group availability due to grinding.

Maize cobs with grains were harvested at a relatively high moisture content (23%) from the field in northern New South Wales, Australia. The cobs were divided into four categories and dried in the sun or artificially in a forced draft oven at 80, 90 or 100 °C for 24 h. The samples were subjected to proximate and detailed nutrient analyses. In vitro nutrient digestibility and ultra structure of samples were also assessed. Proximate analysis of maize revealed that dry matter (DM, 980 g/kg) and ash (1.32 g/kg) content were highest in the 100 °C samples, but crude protein (98.4 g/kg), ether extract (45.0 g/kg) and phytate–P (1.8 g/kg) content were the highest in the sundried samples. Gross energy was little affected by heat treatment but the metabolizable energy value increased with rising temperature. The concentrations of most of the amino acids but not lysine were increased in samples dried at 80, 90 and 100 °C in comparison to sun drying. Total starch, resistant starch (RS) and amylose content were slightly increased by artificial drying while amylopectin was reduced under the same conditions. Starch content (691 g/kg) was highest at 80 °C while RS (363 g/kg) and amylose (304 g/k) were lowest in the same batch. The mineral concentration of samples decreased with increasing temperature except copper, which was slightly increased. The soluble non-starch polysaccharide (NSP) content was increased while the insoluble NSP decreased with increasing temperature. The morphological structure of maize observed under a scanning electron microscope showed some shrinkage of starch granules as a consequence of artificial drying temperature. In vitro digestibility of DM was improved as a result of artificial drying of high moisture maize but starch digestibility was reduced. It may be inferred that the nutritive value of maize grain varies with drying temperature and drying process. These differences may explain changes in nutritive value of the grain when fed to chickens.Keywords: Maize, drying temperature, composition, structure

The influence of different drying temperatures of curd particles in order to obtain curd particles with chemical composition characteristic for Dutch-type semi-hard cheeses was investigated. The experiments were performed with heat-treated milk at 87ºC for 10 minutes to induce chemical interaction between casein and serum proteins and to form the co-called co aggregates. The curd particles were dried at 42ºC and 45ºC for 60 minutes and two types of curd, named curd A and curd B were formed afterwards. The results of the experiments showed that the used temperatures had no significant influence on chemical composition of the curd. The average total solids of curd A was 49.09%, moisture in fat free basis (MFFB) 68.78% protein content 22.23%, lactose content 1.55%, ash 1.98%, titratable acidity 71.700T and pH 6.22. On the other side, the average values for curd B were 49.40%, 68.58%, 22.74%, 1.47%, 1.94%, 75.920T and 6.07, respectively. The use of different drying temperatures, as well as the other treatments (pressing, salting and ripening) provide conditions for semihard cheese producing, with the chemical composition similar to the Dutch-type semihard cheese prepared according to the traditional method. U radu je ispitivan uticaj različitih temperatura sušenja sirnog zrna sa ciljem dobijanja sirnog zrna koje je po sastavu karakteristično za polutvrde sireve holandskog tipa. U ogledima je korišćeno mleko kod kojeg je prethodnom termičkom obradom na 870C u toku 10 minuta, obrazovan hemijski kompleks između kazeina i serum proteina, poznatih u literaturi kao koagregati proteina mleka. Sušenje sirnog zrna izvršeno je na temperaturi od 420C, i nakon toga obrazovana sirna gruda A, i na temperaturi od 450C (sirna gruda B) u vremenu od 60 minuta. Rezultati istraživanja su pokazali da primenjene temperature sušenja nisu imale značajnijeg uticaja na hemijski sastav dobijene sirne grude. Prosečan sadržaj suve materije kod sirne grude A iznosio je 49.09%, sadržaj vode u bezmasnoj materiji sira (VBMS) 68.78% proteina 22.23%, laktoze 1.55%, pepela 1.98%, titraciona kiselost 71.700T i pH 6.22. Prosečan sadržaj suve materije kod sirne grude B iznosio je 49.40% vode u bezmasnoj materiji sira 68.58%, proteina 22.74%, laktoze 1.47% pepela 1.94%, titraciona kiselost 75.920T i pH 6.07. Primenom različitih temperatura sušenja sirnog zrna (42ºC i 45ºC), kao i daljim tehnološkim operacijama (presovanje, soljenje i zrenje) obezbeđeni su uslovi za dobijanje sira koji po hemijskom sastavu odgovara polutvrdim sirevima holandskog tipa, proizvedenim na tradicionalan način.

The in vitro release characteristics of a model hydrophilic drug, clonidine hydrochloride, from pressure sensitive adhesive (PSA) matrices prepared by two coating methods, direct coating on a backing layer and transfer coating (coating on a liner layer and transfer of the resulting PSA onto a backing layer), with different drying temperatures were measured and evaluated. Hydrophilic polymer, polyethylene glycol (PEG), hydroxypropyl cellulose (HPC) or polyvinyl pyrrolidone (PVP) was added to the matrices to increase the drug release rate. A lower drying temperature showed a higher release rate. Each polymer increased the release rate compared to control (without polymer). A PSA matrix with HPC showed a low initial burst followed by a prolonged release, whereas those with PEG and PVP exhibited a high initial burst and a subsequent low release rate. The difference in the initial burst was related, to a considerable degree, to the affinity of the matrices against water. It was also related to the amount of drug on the matrix surface. The transfer coating and addition of HPC were useful in suppressing the high initial burst and in maintaining a high sustained release rate of the drug from the PSA matrices.

International audience; In this paper, experimental water and thermal balances with three proton exchange membrane fuel cells (PEMFC) are proposed. On the test facility of Ecole des Mines de Paris, three De Nora SPA fuel cell stacks have been successfully studied: An 1 kW(e) prototype using Nafion((R)) 117, a 5 and a 10 kW(e) module using Nafion(R) 115. The averaged water symmetry factor determines strategies to avoid drying membrane. So, we propose analytical solutions to find compromises between humidification and cooling conditions, which determines outlet temperatures of gases. For transport applications, the space occupied by the power module must be reduced. One of the main efforts consists in decreasing the operative pressure. Thus, if adequate cooling power is applied, we show experimentally and theoretically the possibility to use De Nora PEM fuel cells with low pressure, without specific external humidification.

Maytenus ilicifolia Mart. ex Reiss, a espinheira-santa verdadeira, é largamente utilizada para tratamento de gastrites e úlceras estomacais. O seu valor terapêutico é atribuído principalmente aos polifenóis (flavonóides e taninos) e triterpenos. Os polifenóis são bastante estudados e estão relacionados à atividade antioxidante exercida pela planta. Existem vários métodos para avaliar a atividade antioxidante, a qual pode ser medida a capacidade antioxidante total utilizando o método de formação do complexo fosfomolibdênio e a atividade antioxidante em relação à redução de um radical, utilizando-se o DPPH (2,2-difenil-1-picrilhidrazila). A atividade antioxidante das folhas de espinheira-santa seca em diferentes temperaturas foi avaliada, visando verificar a possível influência das temperaturas de secagens e seu poder antioxidante. Foram utilizadas cinco temperaturas (40, 50, 60, 70 e 80 ºC) e uma temperatura de secagem de rotina, de um produtor/beneficiador de plantas medicinais. As menores temperaturas apresentaram as maiores atividades antioxidantes. Maytenus ilicifolia Mart. ex Reiss, the true "espinheira-santa" is widely used for treating gastritis and stomach ulcers. Its therapeutic values are due mainly polyphenols (flavonoids and tannins) and triterpens. Polyphenols are largely studied and they are related to the antioxidant activity of the plants. There are several methods for evaluating the antioxidant activity, which can measured the total antioxidant capacity through the formation of a phosphomolybdenum complex and the antioxidant activity related to the reduction of one radical, using the DPPH (2,2-diphenyl-1-picrylhydrazyl). The antioxidant activity of "espinheira-santa" dried leaves in different temperatures was measured in order to evaluated the possible influence of drying temperatures under its antioxidant power. Five temperatures used were (40, 50, 60, 70 and 80 ºC) and a drying routine of medicinal plants as well. Lower temperatures showed the highest antioxidant activities.