نشریه تحقیقات منابع طبیعی تجدید شونده
سال پنجم شماره 4 (پیاپی 18، زمستان 1393)

Black mouth croaker (Atrobucca nibe) is considered as a new and valuable fish stock in the deep water of the Oman Sea. In this study, nonmarket sized of the fish was subjected to produce surimi and kamabako gel manually and changes in the physical and microstructure properties of them during 6 months at freezing conditions were investigated. With increasing storage time, whiteness index from 66.24±0.20% to 60.11±0.23% and gel strength from 583.53±56.583 to 303.60±31.518 cm g-1 reduced after six months at frozen storage. The maximum expressible moisture content of kamabako gel sample (7.42±0.26%) was obtained in six months storage (p<0.05). With increasing storage time, quality score of surimi gel decreased to 3.75±0.500 grade. Due to increase the shelf life, rough and irregular of protein structures were appeared in the protein network of the surimi. The average number of surimi polygonals were significantly decreased from 15038±280 to 10399±564 number per mm2 and their area were significantly increased from 27±0.9 to 84±4.5 μm2, with increasing storage time (p<0.05). The results indicated that in spite of relative decreasing in the functional properties of surimi proteins due to denaturation, produced surimi acceptable after six months at frozen storage.

In this survey, effect of Probiotic Bactocell (Consist of Pediococcus acidilactici MA 18/5M) was examined on feeding, growth performance and survival rate of grass carp (Ctenopharyngodon idella) fry. 300 fish were prepared and fed by special diet made according to American Soybean Association International Marketing (ASA-IM) principle. Four different treatments (control group with no probiotic, treatments 1, 2 and 3 each containing 0.1, 0.2 and 0.3 g probiotic Kg-1 of basal diet, respectively) were designed in triplicates. Results showed that Bactocell has no significant effect on feeding and growth parameters, but treatments 1 and 3 had the best performance. Although there weren’t any significant differences between fishes treated by 0.1 and 0.2 g Kg-1 Bactocell, most of the growth factors including body weight increase, percentage of body weight increase, specific growth rate and protein efficiency rate were better in fishes fed by the diet supplemented with 0.1g Kg-1 Bactocell.

In this study, possibility use of soya stalk flour in natural fibers/plastic composite manufacturing has been investigated. Polyethylene and soya stalk flour in three levels (40, 50 and 60% w/w) and compatiblizer agent in three levels (2, 3 and 4% w/w) were mixed and injection molded. Mechanical and physical properties evaluated using of Factorial Experiment in Completely Randomized Design. Results revealed that mechanical properties in composites with higher content of compatiblizer were greater than others. Also, these properties with increment in soya stalk flour show an increasing trend. Interaction effect of mixture ratio and compatiblizer content on the mechanical properties was statistically significant. The produced composites with 60% soya stalk flour and 4% MAPE had greatest strength. The results show that composite water absorbance after 1344 hours water soaking, with compatiblizer agent increasing and soya stalk flour decreasing has been decreased.

A study was conducted to determine the most appropriate forest road network using GIS software at series7, district 38 of Sardabrood and Chalus in 2013. To investigate and design forest roads, a land digitalized model in TIN format was prepared by 3D map of forest organization in a scale of 1:25000. Then, basic maps such as maps of slope, aspect and contour line distance of 10-m were prepared using this model. In the next step, the map of geology, penology, typology, proposed paths and parcel borders were digitalized based on the booklet of forest management plan. Eight effective factors in designing of forest road networks were investigated such as forest type, geology, pedology, distance from road, hydrography network, geographical aspects of the area, slope, and landscapes. The effect of each factor was weighed using hierarchical analysis. Then in the GIS environment considering the overlapping of aforementioned eight factors, capability road pass map of the area was created. Three variants of various paths in the road quickly predicted and evaluated by inserting the desired longitudinal slope (regarding to the kind of roads) into PEGGER program. The evaluation of the path proposed by the organization and the designed paths was done using Backmond regulations and capability road pass maps. The results showed that the proposed path with the density of 9.39 m per ha and coverage of 85.33% had the most suitable forest road network.

This study evaluated the implementation or non-implementation of predicted project of range plan in Isfahan province. Accordingly, first, the list of range management plans was prepared. Next, the list of predicted projects for each plan was extracted. Afterwards, quantity and quality of information and barriers to project implementation were determined by using the field visits of rangelands, interviews with experts and exploiters of rangelands. The results showed that the predicted projects of Range plans have not completely implemented (average 37/58%). In the meantime, the projects of water container, livestock wells, aqueducts and fountains and pile had the best condition and dry farming, direct seeding had the worst condition. Also The revise of the Range Management Plan, failure to provide banking facilities for projects, weakness monitoring projects, problems with the proximity of range allotments, no exit surplus livestock, venture capital for projects, formulates problems in range, and the lack of consent of plan executors were the most important technical, social and economic barriers. It seems that range plans do not have enough efficiency due to technical, social and economic problems. Therefore, they should be revised in this regard regarding multiuse of rangelands.

in this study, the effect of refining on the optical and mechanical properties of pulp and paper made from recycled banknote paper was investigated. For this purpose, fifty Rials waste banknote papers were cut into strips with a width of 15 mm. First, retail banknote papers were pretreated with acid under conditions pH=3 and 4 hours treatment time in ambient conditions. After acidic pretreatment, a acidic treatment was done under conditions pH=3 and 1.5 to 2 hours treatment time in 95° C, and the amount of consumed acid was 0.3% for banknote papers weight. To separate ink particles from fiber surfaces, a alkaline treatment was performed after acidic treatment under conditions 2 hours treatment time in 95° C, and 3% NaOH for dry pulp weight. After alkaline treatment, obtained pulp was poured into a laboratory mixer and by mixer was stirred in 2 minutes until the fibers are so far apart. Then, the freeness of pulp was measured. Obtained pulp was refined by PFI refiner in refining intensities of 50, 100 and 150 and then, the freeness of obtained pulps were measured. After refining, for each of the pulps, hand sheet papers were made and the properties of them were determined. The results indicated significant differences between pulp and paper properties made of waste currency papers with 4 different refining intensities in 1% confident level. As increasing of refining intensity and refining revolutions, burst strength, tensile strength, folding strength and brightness of papers increased but tear strength of papers and freeness of pulps decreased.

In this study, the effect of soda and kraft pulp of kenaf bast and whole stalk (Cubana cultivar from Hibiscus cannabinus) application on the possibility of improving in recycled packaging paper was investigated. Kenaf bast and whole stalk pulping was conducted by both soda and kraft processes. Pulping conditions included of liquor to kenaf chips ratio of 8:1, cooking temperature of 165 °C, active alkali of 28%, sulfidity of 25% and different cooking time to achieve the target kappa number of 25. Results showed that cooking time in the bast pulping was much lower than that in the whole stalk (25 and 35 in kraft and soda processes, respectively). However, the cooking times in the whole stalk pulping, to achieve the kappa number of 25, were 120 and 180 in kraft and soda processes, respectively. Because the bast to core ratio was 40-60, the combination of kenaf Pulps was conducted about 20% with the constant content of kenaf bast fiber. The findings indicated that kenaf bast pulps had the most strength properties in both of soda and kraft processes, but strength properties of soda whole stalk pulp were lower than kraft whole stalk pulp. In these pulp mixtures, the mixture of kraft pulp of kenaf whole stalk with recycled pulp had the most strength properties.