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141.
Economic analysis of a goldfish (Carassius auratus Linn.) recirculating aquaculture system (RAS) with rearing tank capacity of 5 m3 (RT5) has been evaluated based on two culture period in 2009 and 2010. The stocking density of goldfish was kept at 100 numbers per m3 of rearing water volume. Furthermore, based on the data obtained from RT5, four more hypothetical RASs of rearing tank capacities of 10 m3 (RT10), 20 m3 (RT20), 50 m3 (RT50) and 100 m3 (RT100) were conceptualized for economic analysis that assess and compare the effects of economies of scale on profitability. The payback period, accounting rate of return (ARR), net present value (NPV), profitability index (PI) and modified internal rate of return (MIRR) were evaluated for the different water volumes (up to 100 m3) assuming project life to be 10 years. The economic analysis revealed that a goldfish RAS with rearing tank capacity 20 m3 onwards can be feasible with a payback period less than 4 years, accounting rate of return 54%, net present value of Rs 241820 and modified internal rate of return of 23%. Sensitivity analyses revealed that market price of fish was most sensitive followed by survival rate, labour, maintenance, FCR, initial investment, discount rate, electricity cost and feed cost respectively. Interestingly, feed cost was found to be the least sensitive one.  相似文献   
142.
Taking an area of about 2.3×104 km2 of southeastern Iran, this study aims to detect and predict regional-scale salt-affected lands. Three sets of Landsat images, each set containing 4 images for 1986, 2000, and 2015 were acquired as the main source of data. Radiometric, atmospheric and cutline blending methods were used to improve the quality of images and help better classify salinized land areas under the support vector machine method. A set of landscape metrics was also employed to detect the spatial pattern of salinized land expansion from 1986 to 2015. Four factors including distance to sea, distance to sea water channels, slope, and elevation were identified as the main contributing factors to land salinization. These factors were then integrated using the multi-criteria evaluation (MCE) procedure to generate land sensitivity map to salinization and also to calibrate the cellular-automata (CA) Markov chain (CA-Markov) model for simulation of salt-affected lands up to 2030, 2040 and 2050. The results of this study showed a dramatic dispersive expansion of salinized land from 7.7 % to 12.7% of the total study area from 1986 to 2015. The majority of areas prone to salinization and the highest sensitivity of land to salinization was found to be in the southeastern parts of the region. The result of the MCE-informed CA-Markov model revealed that 20.3% of the study area is likely to be converted to salinized lands by 2050. The findings of this research provided a view of the magnitude and direction of salinized land expansion in a past-to-future time period which should be considered in future land development strategies.  相似文献   
143.
144.
The aim of this experiment was to evaluate the symptoms, variation, and correlation of hematological factors and some parameters of the innate immune response of the infected rainbow trout (Oncorhynchus mykiss) fish with Lactococcus garvieae bacteria. A total of 270 fish were divided into three groups including infected fish with a high and low concentration of L. garvieae and a control group without infection. The blood and tissue (brain, head, kidney, and spleen) samples were collected from each group (n?=?6 fish) at 0, 3, 14, and 21 days after treatment. The most observed symptoms during infection were lethargy, exophthalmia, and ascites. The mortality rates for the high and low dose-infected fish were defined as 60 and 25%, respectively. The infected groups had significantly (p?<?0.05) higher activity of serum lysozyme, myeloperoxidase, classical and alternative pathways of complement, serum bactericidal effects, and the specific antibody titer. Also, a significant (p?<?0.05) lower hematocrit and hemoglobin levels and higher white blood cell numbers were observed in the infected groups. A significant correlation was observed between the CRP levels and some of the hematological and immunological indices as bactericidal effects, classical complement pathways, lysozyme activity myeloperoxidase activity, white blood cell numbers, and hematocrit levels. The clinical symptoms, immune responses, and hematological indices variation among L. garvieae-infected fish are dependent on the duration and bacterial dose of the infection.  相似文献   
145.
The purpose of the present study was to investigate the toxicity of cryoprotectants on the hatching rate of rainbow trout (Oncorhynchus mykiss) embryos. Epiboly and first eye pigmentation stage embryos were immersed in six permeable cryoprotectants, dimethyl sulfoxide (DMSO), glycerol (Gly), methanol (MeOH), propylene glycol (PG), ethylene glycol (EG), and acetamide (Ac), in concentrations of 1–5 M for 5 or 10 min and two non-permeable cryoprotectants, sucrose (Suc) (10%, 15%, 20%) and polyvinyl pyrrolidone (PVP) (5%, 10%, 15%) for 5 min. The embryos were then washed and incubated until hatching occurred. The toxicity of the cryoprotectant was assessed by the hatching rate. The results illustrated that permeable cryoprotectant toxicity for rainbow trout embryos increased in the order of PG < DMSO < MeOH < Gly < EG < Ac. The hatching rate of the embryos treated with permeable cryoprotectants decreased (P < 0.05) with increased concentration and duration of exposure. There were no significant decreases in hatching rate of embryos treated with sucrose and PVP with the increase of concentration; sucrose had higher hatching rates than PVP. Rainbow trout embryos at first eye pigmentation stage exhibited greater tolerance to cryoprotectants than embryos at epiboly stage.  相似文献   
146.
In this study, the effect of a vacuum impregnation (VI) process with pulsed electric field (PEF) pretreatment on fortification of whole potato with ferric pyrophosphate was investigated. The VI process and PEF pretreatment were optimized with respect to physicochemical attributes of PEF-VI-processed samples using response surface methodology (RSM). The results indicated that the iron content of VI-processed and PEF-VI-processed potatoes was increased about 126 and 457%, respectively, compared to unprocessed potatoes. A more intensive PEF pretreatment led to a higher cell disintegration, decrease in colour and textural parameters and also increase in components leakage from treated potato. Our study suggests that whole 180-g potatoes should be pretreated at 394 V/cm with 36 pulses and then treated at 3.5 kPa for 37 min in vacuum stage and 39 min restoration time in atmospheric stage to achieve the highest iron fortification and the lowest physicochemical changes during PEF-VI processing.  相似文献   
147.
As the use of high performance textiles has grown, the need for chemical finishes to provide the fabric properties required in the special applications has grown accordingly. In this project, a series of water dispersible polyurethanes dispersion (CS-PUs) with multipurpose performance profile was developed using isophorone diisocyanate (IPDI), polyethylene glycol (PEG), 2,2-dimethylol propionic acid (DMPA) and chitosan (CS) for textile applications. In two step synthesis process, NCO functional PU prepolymers prepared by reacting IPDI, PEG, and DMPA were extended with varying molar quantities of chitosan followed by structural characterization through FTIR. The prepared CS-PU dispersions were applied onto the dyed and printed poly-cotton blend fabrics. The performance behavior of the treated fabric in terms of crease recovery, tear strength, tensile strength, and antibacterial properties was evaluated by applying standard test methods. These investigations show that the CS-PU dispersions can be applied as antibacterial textile finishes with significant improvement in the physical and mechanical properties of poly-cotton fabrics.  相似文献   
148.
Novel acetylation process by substitution of acetic anhydride substitution with hydroxyl groups on nanocellulose (NCC) has been explored to increase its dispersion and interaction in nitrile butadiene (NBR) matrix. The crystallinity index was increased after modification when compared to unmodified NCC, but no significant different with increases of treatment time from 1 hour to 3 hours treatments proven by X-ray diffraction (XRD) results. The Fourier transform infra-red (FTIR) showed the existent of acetyl groups on surface of the NCC after treatment by existent of the peak 1736 cm-1 that attributed to carbonyl groups some peaks were observed at 1430, 1361 and 1248 cm-1 and confirmed on the acetylation process. The nuclear magnetic resonance (NMR) also show the present of acetyl groups by existent of the signal of proton methyl group at 1.90 ppm and new peaks at 5.42, 4.70 and 4.34 ppm, for all ACN samples. The thermal results by thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC) showed that the acetylated NCCs were 10 % more thermally stable. Transmission electron microscopic (TEM) results showed that no significant changes were observed due to the acetylation process. The results also showed well distributed of individual NCC after acetylation, this improvement was primarily attributed to uniform dispersion of the ACN-NCC and less aggregated occurred. Due to its hydrophobic characteristics, highly crystalline and nano size, ACN-NCC brought a significant improvement up to 25 % on the mechanical properties of nitrile butadiene (NBR) rubber composites.  相似文献   
149.
We report a facile approach to fabrication and characterization of cationic titanium dioxide (TiO2+) on poly (vinyl alcohol)/poly (acrylic acid) (PVA/PAA) composite electro-spun nanofibrous mat. The aim of this study is to develop a “functional electrospun nanofibrous mat” as a sustainable approach to superior photocatalytic degradation of organic colorants. For that, the PVA/PAA nanofibrous mat was prepared by electrospinning of PVA and PAA solution according to an aspect ratio of 1:1 and later water stability was induced by the thermal cross linking at an elevated temperature of 145 °C for 30 minute. By means of electrostatic layer-by-layer (LbL) assembly, cationic titanium dioxide (TiO2+, ~19 nm) was immobilized on the surface of the water stable nanofibrous mat. As functionalized composited nanofibrous mat was characterized by using scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis and thermogravimetric analysis (TGA). Superior competency of the functionalized nanofibrous mat towards photocatalytic degradation of organic dye (methyl blue) in aqueous solution was observed by using UV-visible spectrophotometer with quantitative measuring method. The result indicates a complete degradation of methyl blue within 40 mins and superior reusability upto 5 cycles application. The study signifies the prospect of using electrospun nanofibers to manipulate the catalytic activity, which could be a foundation for further rational design of various composite nanofibrous materials.  相似文献   
150.
The present study assessed the effect of arbuscular mycorrhizal fungi (AMF) on broomrape (Orobanche aegyptiaca Pers.) control to determine its effects on tomato (Lycopersicon esculentum L.) growth indices. This experiment was carried out using a randomized complete block design with four replications. The treatments included three strains of AMF (Glomus mosseae, Glomus intraradices and Glomuse hoe ) at three levels (100, 200 and 300 kg ha?1). The control treatments (without mycorrhiza) were with and without broomrape (weed infest and weed free). The results showed that the use of G. intraradices and G. mosseae decreased broomrape seed germination, the number of nodules and the dry weight of the broomrape and increased root area and dry weight of the tomato plant when compared to G. hoe and the control treatments without broomrape. The tomato yield in G. intraradices 300 kg ha?1 treatment increased by 10 and 205% than weed free and weed infest treatments, respectively. Finally, G. intraradices and G. mosseae at, respectively, 200 and 300 kg ha?1 are recommended for land under tomato cultivation that has been contaminated with broomrape.  相似文献   
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