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11.
Energy recovery from a crossflow ultrafiltration (UF) membraneunit employed in order to improve the performance of an anaerobic contact digester for the treatment of brewery wastewater was assessed. The performance of the pilot-scale anaerobic UF membrane system was studied for over 15 months. At steady-state conditions, an organic loading rate of 28.5 kg COD m-3 d-1, a hydraulic retention time of 4.2 days and overall COD and BOD removal efficiencies of 99% and almost 100% were achieved, respectively. Percent methane in biogas was found to be in a range of 67–79% with the corresponding methane yield of 0.28–0.35 m3 CH4 kg-1 CODremoved. The potential energy recovery from the system treating brewery wastewater at an OLR of 28.5 kg COD m-3 d-1 was 87 MJ d-1 which would enable to maintain all energy requirements of the feed pump, mixing and heating of the reactor contents. In addition to this, 71% of the energy requirement for recirculating the reactor content through the membranes would also be recovered.  相似文献   
12.
The objective of this study was to develop two methods to predict the volume of whole Alaska pollock and to compare the results with the experimentally measured volumes. One hundred fifty-five whole pollock, obtained from a Kodiak processor, were individually immersed in a graduated cylinder equipped with an outflow tube to catch the displaced water as a result of immersion. The weight of the water was recorded. Then the fish were placed in a light box equipped with a digital video camera, and the side view and top view recorded (2 images for each fish). A reference square of known surface area was placed by the fish. A cubic spline method to predict volume by integration of cross-sectional area slices based on the top and side views and an empirical equation using dimensional (length L, width W, depth D) measurements at three locations of the fish image were developed. The R2 value for the correlation between the L × W × D versus measured volume was 0.987. The best R2 for the correlation of the predicted volume by the cubic spline method versus the measured volume was 0.99. Image analysis can be used reliably to predict the volume of whole Alaska pollock.  相似文献   
13.
Bali cattle (Bos javanicus) account for about one quarter of the total cattle population in Indonesia and are particularly important in the smallholder farming enterprises of the eastern islands. The population of Bali cattle is declining in most areas of Eastern Indonesia because demand for beef cattle exceeds the local capacity to supply these animals. Indonesian agencies recognise that new strategies are required to improve the productivity of Bali cattle and to address major constraints relating to animal husbandry and nutrition. To date, the adoption of cattle improvement technologies has been historically slow in Indonesia, as is the case elsewhere.This paper reports on key findings from a long-term study conducted between 2001 and 2009 with smallholder households from six villages in South Sulawesi and Central Lombok, to develop and test an approach for evaluating and increasing the adoption of cattle and forage improvement technologies. The approach is based on the principles of farming systems and participatory research and involved four main steps; (1) benchmarking the current farming system; (2) identifying constraints to cattle production and strategies to address them; (3) desktop modelling of the production and economic impacts of selected strategies; and (4) on-farm testing of the most promising strategies with 30 participant smallholder households.The approach was found to be successful based on: (1) sustained adoption of a package of best-bet technologies by the 30 participating households; (2) evidence of positive production, social and economic impacts; and (3) significant diffusion of the cattle improvement technologies to other households in the project regions.  相似文献   
14.
The experiments were carried out between 2003 and 2005 in the Province of Amasya. The first objective of the study was to determine the best pollinizer for the cultivar ‘0900 Ziraat’ which is the most popular sweet cherry cultivar (Prunus avium L.) in Turkey. The ‘0900 Ziraat’ was used as a female parent and ‘Türko?lu’, ‘Köro?lu’, ‘Kargayüre?i’, ‘Hac? Ali’, ‘Starks Gold’ and ‘Geçkiraz’ were used as pollinizer cultivars. In 2003, for the hand cross pollination combinations, fruit set was between 31.25% and 42.80%. In 2004, fruit set was reduced by spring frost and was between 9.69% and 15.24%. Additionally, the blooming periods of the experimental cultivars, fruit set of open pollination and hand self pollination were examined. The fruit set ratios of all tested cultivars under open pollination conditions varied between 26.73% and 53.49% in 2003 and 4.38% and 38.35% in 2004. ‘Geçkiraz’ had the highest fruit set owing to its late flowering date. For open pollination, fruit set values of ‘0900 Ziraat’ were lower than hand cross pollination with other cultivars in 2003 when the results of both treatments are compared. On the contrary, fruit set was higher than hand cross pollination in 2004. In the present study, pollen germination values varied greatly among year, cultivar and sucrose concentration. Viability percentages were generally high, not less than 66%. According to phenological observations, partial or complete overlapping of the flowering period of ‘0900 Ziraat’ and its possible pollinizer cultivars were observed in 2003 and 2005. But in 2004, the flowering period overlapped for only ‘0900 Ziraat’ and ‘Geçkiraz’ cultivars. When blooming times are taken into consideration, ‘Geçkiraz’ was found to be the best pollinizer cultivar.  相似文献   
15.
ABSTRACT

The present study evaluated the effect of whey protein isolate (WPI) coating enriched with thyme essential oil (EO; 3, 5, and 7%, v/v) on whole trout chemical and microbial quality during refrigerated storage at 4 ± 2°C. As a result of this study, the addition of thyme essential oil to WPI coatings enhanced quality significantly better than that of the control and WPI coating without thyme essential oil during refrigerated storage, and this effect increased with an increase in the thyme EO concentration in WPI coating.  相似文献   
16.
Changes in the acetoclastic methanogenic activity in the effluentfrom an upflow anaerobic filter (UFAF) were studied throughout a 36 week operating period. The UFAF formed the second phase of a two-phase laboratory-scale anaerobic treatment system. TheSpecific Methanogenic Activity (SMA) test was used to measurethe acetoclastic methanogenic activity of the biomass washed outfrom the UFAF. Throughout the operating period, the SMA testswere carried out at different organic loading rates (OLR) up to6.7 kg COD m-3 d-1 and upflow velocities (UV), 5 m d-1 and 15 m d-1. The results showed that thebiomass washed out from the UFAF consisted of up to 55%(considered as a draft value) acetoclastic methanogens producing550 mI CH4 g-1 VSS d-1. This high acetoclasticmethanogenic activity measured in the effluent might have beendue to the existence of Methanosaeta (formerly Methanothrix) species. Towards the end of operation,Epifluorescence Microscopic examinations in the effluent revealedthat Methanococcus species were the most dominant groupfollowed by medium rods and short rods, filaments and long rodsand the least dominant Methanosarcina species. Theperformance of the UFAF was not adversely affected by the loss ofthe active biomass and changes in their composition. The UFAFsystem achieved over 85% COD removal efficiency at thehighest OLR of 6.7 kg COD m-3 d-1 and UV of 15 m d-1. Throughout most of the operation, methane yield rangedfrom 0.28–035 m3 CH4 kg-1 CODremoved.  相似文献   
17.
ABSTRACT

Due to high production cost and prevention of environmental pollution, it is important to reduce the amount of nitrogen (N) fertilizer used on wheat (Triticum aestivum L.). The aim of this study was to evaluate N use of 6 × 6 diallel wheat F2 progenies and parental lines at low (N0, no N fertilizer) and high (N+, 160 kg N ha? 1) N levels. Significant differences were found between N+ and N0 application in grain N content, grain N yield, N use efficiency for grain N yield (NUEgn), and N use efficiency for grain yield (NUEgy). The cultivar ‘84ÇZT04’ showed positive and high general combining ability (GCA) effects for all traits at low N level. Also, it was the best combiner for all traits at both N levels. The cultivar ‘Genç 99’ was the best parent for GCA effects for grain yield and NUEgy. Hybrids ‘Genç 99 × 84ÇZT04’ and ‘84ÇZT04 × Weaver’ showed positive specific combining ability (SCA) effects for all investigated traits at low and high N levels. Variety ‘84ÇZT04 × Apogee’ had the best SCA effects for all traits at low N level. Overall, the data suggest that it is probable to select promising lines suitable for low N conditions by the crossing of high N use efficient parents.  相似文献   
18.
New subspecies-specific primers for the detection of Acidovorax avenae subsp. citrulli ( Aac ), the seedborne bacterium which causes bacterial fruit blotch of cucurbits, were designed based on PCR fragments obtained in ERIC- and BOX-PCR profiles of Aac strains. PCR with both primer sets identified 30 strains from different locations and hosts, but did not amplify DNA from other closely related species and subspecies assessed, with the exception of DNA of one strain of A. avenae subsp. avenae , which was amplified by one of the primer sets, named BX-S. This primer set, based on a BOX-PCR fragment, performed under high-stringency conditions without losing its detection sensitivity. The primers were also evaluated for their ability to detect the pathogen in contaminated watermelon and melon seed samples. The BX-S primers facilitated the detection of the pathogen from washings of 5000-seed samples with 0·02% infestation. This primer set was also assessed for detection using immunomagnetic separation polymerase chain reaction (IMS-PCR) and was shown to be as sensitive as a previously described primer set (AACF2/R3), detecting 0·02% infestation in seed samples. This highly specific and sensitive primer set could be used to improve PCR-based detection of this important pathogen.  相似文献   
19.
The diversity of 40 strains of Ralstonia solanacearum causing bacterial wilt of potato in the major potato-growing areas of Iran was assessed. Based on rep-PCR genomic fingerprinting, strains fell into two distinct groups. The first group contained 37 of the 40 strains and the second consisted of three strains from a narrow tropical region in Iran. The three strains from the narrow tropical region were found to be phenotypically and genotypically most similar to R. solanacearum biovar 2T strains, whereas all other strains were phenotypically and genotypically identified as being R. solanacearum biovar 2/race 3. Phylogenetic analysis of endoglucanase gene sequence information of two of the strains from the tropical region revealed that they belonged to phylotype II of the R. solanacearum species complex and had 100% sequence similarity to a biovar 2T strain from potato in Peru. This is the first report of the presence of R. solanacearum phylotype II/biovar 2T in Iran and the first report of the existence of this group of R. solanacearum outside South America.  相似文献   
20.
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