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81.
Fiber quality is very important for all the steps of the textile area. Underwater shock wave has been utilized for metal,
wood, food processing and medical applications and renewed and increased application during the last decade. The main object
of this study, is to demonostrate underwater shock wave as a surface treatment of natural fibers such as jute and cotton in
form of yarn and to report characterized properties of the treated fibers. The underwater shock wave was generated by the
explosion of the detonation fuse in the water tank. The process of bubble generation and expansion inside the water results
in the formation of shock wave. Natural fibers were exposed to shock wave treatment depending on the different pressures and
detonatinon fuse separation distance. After shock-loading, fibers were selected for physicomechanical and physicochemical
tests such as Scaning Elecron Microscopy (SEM) analysis, breaking strength, moisture behavior, permeability and wicking test.
The maximum effect with improved moisture content, permeabilty and wicking properties were observed from 100 MPa. The treated
fiber showed high performance necessary for use in woven and non woven purpose. 相似文献
82.
[目的]对新疆霍城县大西沟采集的两种形异羊肚菌(XJURML4和XJURML5)进行分类鉴定.[方法]用真菌专一引物ITS1f和ITS4扩增两菌ITS区并进行序列分析.[结果]XJURML4 ITS片段1 130 bp( EU086775),XJURML5 ITS片段1 127 bp(EU086776).两菌的ITS2区100;相似,而ITS1区仅有4 bp差异.BLAST比对测序结果发现XJURML4和XJURML5与近缘种宽圆羊肚菌(MorcheLLa esculenta (L.:Fr.)Pers.var.rotunda Pers.:Fr.)的同源性为99.28;和98.65;;NJ法构建进化树分析ITS序列,两菌也跟宽圆羊肚菌类聚在一起.随机引物OPA3进行RAPD扩增,共产生出六条带,二条相同,剩余四条为多态性条带,表明两菌基因组上也有差异.[结论]ITS区序列和进化树分析、OPA3 - RAPD标记技术均表明两菌是宽圆羊肚菌种内的新变种,而与传统形态学鉴定结果不一致. 相似文献
83.
Sahena Ferdosh Nik Norulaini Nik Ab Rahman Md. Jahurul Haque Akanda Kashif Ghafoor Mohd. Omar Ab Kadir 《Journal Of Aquatic Food Product Technology》2013,22(2):230-239
ABSTRACTFish oil was extracted and simultaneously collected into six fractions based on molecular weight and the chain length of triglycerides in terms of fatty acid constituents without splitting of the triglycerides, using supercritical carbon dioxide (SC-CO2) at optimized conditions of 40 MPa, 65°C, and a flow rate 3 mL min?1. In each type of fractionation, the first fraction (F1) was rich in saturated fatty acids (SFA; 52.57 to 61.26%), followed by monounsaturated fatty acids (MUFA; 22.17 to 23.22%) and polyunsaturated fatty acids (PUFA; (0.54 to 20.37%); the sixth fraction (F6) was rich in PUFA (48.93%), followed by MUFA (33.59%) and SFA (13.61%). It was obvious that short-chain fatty acids were extracted at an earlier fraction; therefore, the latter fractions were dominant in long-chain fatty acids, especially MUFA and PUFA. Thus, omega-3 fish oil (last three fractions) was successfully separated to be used as a value-added health product. 相似文献
84.
Atena AdnaniMahiran Basri Naz ChaibakhshMohd Basyarudin Abdul Rahman Abu Bakar Salleh 《Industrial Crops and Products》2011,33(1):42-48
Artificial neural network (ANN) analysis of immobilized Candida antarctica lipase B-catalyzed esterification of palmitic acid with xylitol was carried out. Temperature, time, amount of enzyme, amount of molecular sieve, substrate molar ratio and volume of solvent were the six important parameters used as the inputs of the network trained by Levenberg-Marquardt (LM) algorithm. After evaluating different ANN configurations, the best network was found to be consisted of two hidden layers with six and seven neurons in the first and second layers respectively, using a hyperbolic tangent sigmoid transfer function. The coefficient of determination (R2) and mean square error (MSE) values between the actual and predicted responses were 1 and 1.5025e−24 for the training and 0.97239 and 0.03259 for the testing datasets. The results indicate the good generalization performance of the neural network model and its capability to predict the conversion of the substrates. 相似文献
85.
Influences of dietary distillers dried grain level on growth performance,body composition and biochemical parameters of juvenile olive flounder (Paralichthys olivaceus) 下载免费PDF全文
This study was conducted to investigate the influence of dietary distillers dried grain (DDG) level on growth and body composition of juvenile olive flounder (Paralichthys olivaceus). Five diets (designated as DDG0, DDG7, DDG14, DDG21 and DDG28) were prepared to contain 0, 70, 140, 210 and 280 g kg?1 DDG. Three replicate groups of fish averaging 11.6 ± 0.1 g were fed one of the diets for 8 weeks. Weight gain of fish fed diets containing 70–280 g kg?1 DDG was not different to that of fish fed DDG0 diet (P > 0.05). Feed efficiency of fish fed DDG21 and DDG28 diets was lower than that of fish fed DDG0 diet (P < 0.05). The antioxidant enzyme and digestive enzyme activities were not affected by dietary DDG levels. The results of this experiment suggested that DDG is a valuable ingredient as a candidate to replace wheat flour in the diet and could be used up to 280 g kg?1 for the growth of olive flounder. On the other hand, if lower feed efficiency of fish fed 210–280 g kg?1 DDG is considered, up to 140 g kg?1 DDG in diet is recommended for optimum feed utilization of fish. 相似文献
86.
Effects of C/N ratio and periphyton substrates on pond ecology and production performance in giant freshwater prawn Macrobrachium rosenbergii (De Man, 1879) and tilapia Oreochromis niloticus (Linnaeus, 1758) polyculture system 下载免费PDF全文
M Rezoanul Haque M Ashraful Islam M Mojibar Rahman Mst Farzana Shirin M Abdul Wahab M Ekram Azim 《Aquaculture Research》2015,46(5):1139-1155
The production performances of giant freshwater prawn Macrobrachium rosenbergii and Nile tilapia Oreochromis niloticus in C/N‐controlled periphyton‐based polyculture systems were evaluated in triplicate. Three different management practices were compared: the traditional practice without addition of periphyton substrates and carbohydrate (Control), addition of maize flour to maintain a carbon: nitrogen rate of 20:1 (treatment CN) and addition of both maize flour and periphyton substrates (treatment CN+P). This experiment used a pre‐optimized stocking density of tilapia and freshwater prawn by Asaduzzaman et al. Aquaculture [286 (2009) 72]. All ponds were stocked with prawn (3 m2) and monosex Nile tilapia (1 m?2). Bamboo side shoots were posted vertically into the pond bottoms as periphyton substrate covering an additional area of 171 m2 for periphyton development. A locally formulated and prepared feed containing 17% crude protein with C/N ratio close to 15:1 was applied twice daily in all ponds considering the body weight of freshwater prawn only. Water quality parameters, except total alkalinity did not vary significantly (P > 0.05) among treatments. Both, organic matter and total heterotrophic bacterial loads (THB) in the sediment were significantly (P < 0.05) higher in treatment CN+P followed by treatment CN and control. Periphyton biomass in terms of dry matter and chlorophyll a values constantly decreased during the culture period. Substrates contributed 66% and 102% higher net yield of freshwater prawn than CN and control treatment respectively. 相似文献
87.
Roziana Kamaludin Mohd Hafiz Dzarfan Othman Siti Hamimah Sheikh Abdul Kadir Ahmad Fauzi Ismail Mukhlis A. Rahman Juhana Jaafar 《Water, air, and soil pollution》2018,229(11):363
Bisphenol A (BPA) and reactive black 5 (RB5) dye are among the most persistent and non-biodegradable contaminants in water which require an urgent need for the development of effective removal method. The ubiquitous existence of both contaminants could interfere with the human health and aquatic environmental balance. Photocatalytic process as one of advanced oxidation processes (AOPs) has shown high performance for degradation of organic compounds to the harmless materials under sensible condition. Therefore, this study aims to develop a visible-light-driven photocatalyst that can efficiently degrade BPA and RB5 present in household water. N-doped TiO2 were successfully synthesized via simple and direct sol–gel method. The prepared TiO2 nanoparticles were characterized by field emission scanning microscope (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and Brunauere Emmette Teller (BET) analysis. The incorporation of nitrogen in TiO2 lattice exhibited excellent optical responses to visible region as revealed by UV–Vis–NIR spectroscopy absorption capability at 400–600 nm. The photocatalytic activity of the N-doped TiO2 nanoparticles was measured by photocatalytic degradation of BPA and RB5 in an aqueous solution under visible-light irradiations. Degradation of BPA and RB5 was 91.3% and 89.1%, respectively after 360 min illumination. The degradation of BPA and RB5 by N-doped TiO2 was increased up to 89.8% and 88.4%, respectively under visible-light irradiation as compared to commercial TiO2 P25. This finding clearly shows that N-doped TiO2 exhibits excellent photocatalytic degradation of BPA and RB5 under visible irradiation, hence have a promising potential in removing various recalcitrant contaminants for water treatment to fulfill the public need to consume clean water. 相似文献
88.
Md. Abiar Rahman Masakazu Tani Kazuo Asahiro S. M. Asik Ullah 《Small-Scale Forestry》2017,16(3):295-309
A homestead is an integrated production system where trees, crops, livestock and poultry are found in and around the household residence in Bangladesh. It is a potential production unit that provides various product, service and ecological functions. Almost all people in Bangladesh including landless households have homesteads in which they grow trees and crops even in a small piece of land. This study characterizes the species composition, diversity and productivity of the homestead production system in the Teknaf peninsula, southeastern Bangladesh. Survey data collection was from a total of 180 homesteads covering five household categories: large, medium, small, marginal and landless. Vegetable, fruit, timber, and livestock and poultry were common components in the homestead production system. Various types of plants were mainly concentrated in back yards, front yards, boundaries and corners of homesteads. The mean number of tree species per homestead was about 15. In total, 189 tree and shrub species were recorded, and were distinctly high and low in the large (363.7) and landless (55.7) household categories. Species composition, diversity and productivity of homesteads were found to be related to household categories. Richness and diversity of tree and shrub species increased with household size. Betel nut was the dominant tree species followed by mango, jackfruit and coconut. Annual income from homesteads also varied among the household categories, with a mean contribution of the homestead to annual income of about 25 %. A large portion of homestead income came from betel nut trees. There is scope to increase species diversity and income by designing homesteads with the engagement of women and other family members. 相似文献
89.
90.
Shoot and fruit borer, Leucinodes orbonalis Guenee, is a serious pest of eggplant (Solanum melongena L.). Management practices of this obnoxious pest are limited to frequent spray of chemical insecticides. Due to increasing
levels of resistance of L. orbonalis to different insecticides there is an urgent need to test new chemicals. In this study, nine insecticides such as azadirachtin
0.03EC, abamectin 1.8EC, flubendiamide 24WG, chlorpyriphos 20EC, cartap 50SP, carbosulfan 20EC, thiodicarb 75WP, cypermethrin
10EC, and lambdacyhalothrin 2.5EC belonging to different chemical groups were tested against eggplant shoot and fruit borer
in laboratory and field. In laboratory trial, carbosulfan and flubendiamide showed the highest toxicity against fourth instar
larvae of L. orbonalis after 24 and 48 h of exposure, respectively. In field trials, they reduced more than 80% shoot and fruit infestation in winter,
and 80% shoot and 70% fruit infestation in summer over control. Carbosulfan protected the highest amount of healthy fruit
yield in both cropping seasons. Flubendiamide also showed the similar efficacy. Cartap and thiodicarb were moderately effective
in both the seasons. Efficacy of cypermethrin and abamectin was moderate in winter but low in summer. Lambdacyhalothrin and
chlorpyriphos although reduced shoot and fruit infestation of eggplant and protected higher yield as compared to control,
their effectiveness was not satisfactory. The performance of azadirachtin against the pest both in the laboratory and field
trials was the poorest while that of carbosulfan and flubendiamide was the best. Thus, it is suggested that carbosulfan and
flubendiamide may be used for the control of L. orbonalis in eggplant. 相似文献