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文丘里(Venturi)吸鱼泵研究 总被引：2，自引：0，他引：2
介绍了文丘里(Venturi)射流吸鱼泵的结构、原理及应用。文丘里吸鱼泵无叶轮,靠水射流产生负压来抽送活鱼,输送过程中活鱼无损伤,每小时输送活鱼(鱼水混合)20 t,扬程5 m,效率高,适用于深水网箱养殖。 相似文献
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本文介绍了近年来国内外吸鱼泵的主要应用领域和发展前景,吸鱼泵作为远洋捕捞和网箱养殖业的机械化设备,可以快速输送渔获物,改变了过去人工处理费时费力的状况。确保鱼体无损伤并提高存活率是目前吸鱼泵研究的重点。本文讨论了离心式、真空式和射流式吸鱼泵主要机型的结构形式、技术特点和性能水平;并结合各种鱼泵的结构形式说明其优缺点,分析其在我国淡水养殖、深水网箱养殖、远洋捕捞以及渔业资源保护监测中的应用前景和改进措施,以期推进吸鱼泵在国内的普及应用,提高渔业机械现代化水平。 相似文献
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草鱼三大病并发的防治方法王志迁草鱼烂鳃、肠炎、赤皮三种病并发时，表现症状主要是：病鱼肛门红肿突出，肠管发炎，呈紫红色；鳃丝腐烂，带有污泥，鳃盖骨内表皮往往部分烂掉；鱼体表出血发炎，鳞片松离或脱落，鱼鳍基部充血，鳍条间的组织被破坏，未端腐烂。防治方法如... 相似文献
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国内外吸鱼泵研制现状 总被引：2，自引：0，他引：2
本文介绍了国内外研制的真空吸鱼泵、离心吸鱼泵、气力吸鱼泵、射流吸鱼泵等概况,着重就美国“ETI”公司生产的SILKSTREAM射流吸鱼泵的工作原理、结构、性能作了较详细的阐述,供今后研制开发参考。 相似文献
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吸鱼泵是水产养殖和商业捕捞中用于渔获起捕、运输,提高生产效率的主要工具。确保鱼体无损伤并提高存活率是吸鱼泵研究的重点。本文介绍了国内外吸鱼泵的研究现状,讨论了离心式、真空式和射流式吸鱼泵主要机型的技术特点和性能水平;分析了美国、日本及欧洲等国在泵体结构优化、吸鱼泵扩展系统、吸虾泵和网囊泵吸系统等方面的研究进展。针对目前存在的鱼体损伤率高、效率偏低、机体笨重和能耗偏高等问题,提出了我国吸鱼泵技术的发展对策:需重点解决鱼体无损传输、增强通用性、提高智能化水平以及开发远洋渔业连续捕捞系统等问题。 相似文献
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射流泵利用流体力学的原理，以水或空气为工作流体，使流体变速、动能转变，形成负压(真空)而应用在输送气体、液体、固体物料等方面。 相似文献
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A. M. THOMPSON J. GLASGOW T. BUEHRENS E. G. DRUCKER 《Fisheries Management and Ecology》2011,18(4):333-338
Abstract Hidrostal pumps have been successfully employed in live fish transport, yet their effectiveness in fish passage is incompletely understood. This study investigates juvenile salmonid mortality in experimental passage trials through Hidrostal pumps at an agricultural pump facility in Washington State, USA. The effects of impeller pitch, rotational speed and fish body size on passage survival were examined. Hatchery‐reared salmonids [Oncorhynchus mykiss (Walbaum) and Oncorhynchus kisutch (Walbaum)] were introduced to low‐ and high‐pitch impeller assemblies operating at two speeds. Instantaneous mortality rates ranged from 0 to 4% for high‐pitch trials and from 3 to 10% for low‐pitch trials. Larger fish experienced sublethal injury at higher rates (approximately 60% injured) than smaller fish (approximately 23% injured) and exhibited greater susceptibility to injury at higher pump speed. Injury between trials was compared by ranking according to severity and summed for each treatment; greater injury severity was found for the low‐pitch impeller and from higher rotational speeds. Although injury and mortality rates to fish passing through Hidrostal pumps may be reduced through the use of higher‐pitch impellers and lower operational speeds, the use of pump‐bypass facilities may be warranted where acceptable impact thresholds are low. 相似文献
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Edmund P Nunnallee Earl F Prentice Bruce F Jonasson Whitney Patten 《Aquacultural Engineering》1998,17(4):261-272
In the spring of 1996 and 1997, a prototype 400 kHz flat-plate (pass-by) passive integrated transponder tag interrogation (PIT tag) system was installed at the terminus of the downstream migrant (DSM) channel of the Bonneville Dam First Powerhouse, located on the Columbia River. The system was designed to interrogate previously PIT tagged juvenile salmonids migrating down the Columbia River without interfering with the traditional subsampling of fish passing through the facility. In addition, the design enables fish of virtually any size, and debris, to pass over the system's antennas without the port restrictions imposed by traditional pass-through PIT tag interrogation systems. We describe the fish facility in addition to the flat-plate system and its operation. The system tag reading efficiency was evaluated during 1996 and 1997 using a direct method based on the release of known numbers of tagged test fish and an indirect statistical procedure based on tagged run-at-large fish. The results showed that PIT tag reading efficiency during both years using the direct method averaged 97%, while that using the statistical procedure averaged 99% for the dual multiplexed antenna array. During the 1996 and 1997 field seasons 4371 and 14 733 fish, respectively, were recorded. Daily system functionality was monitored using stick tests (i.e., the passing of PIT tagged sticks across the antenna array). 相似文献
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慢性氨氮暴露诱发黄颡鱼幼鱼谷氨酰胺积累、氧化损伤及免疫抑制的研究 总被引：2，自引：2，他引：0
为了研究慢性氨氮胁迫对黄颡鱼幼鱼生长性能、大脑谷氨酰胺积累、肝脏抗氧化酶活性、非特异性免疫应答及抗嗜水气单胞菌感染能力的影响,实验挑选初始体质量为(1.94±0.05)g的健康黄颡鱼幼鱼180尾,开展为期56 d的慢性氨氮胁迫实验.结果表明,实验鱼的终末体质量、增重及饲料效率,氨氮组与对照组无显著性差异,但肝体比氨氮组显著高于对照组;氨氮组实验鱼大脑中氨氮和谷氨酰胺含量显著高于对照组,但谷氨酸含量各组间无显著性差异;氨氮组实验鱼肝脏中超氧化物歧化酶、过氧化物酶及谷胱甘肽过氧化物酶活性显著低于对照组,但硫代巴比妥酸反应物含量氨氮组显著高于对照组;氨氮组实验鱼肝脏中溶菌酶活性、头肾巨噬细胞吞噬指数和呼吸爆发显著低于对照组;感染嗜水气单胞菌14d后,氨氮组和对照组实验鱼累计死亡率无显著性差异.研究表明,黄颡鱼幼鱼遭受亚致死浓度的慢性氨氮胁迫,能够导致大脑中谷氨酰胺含量升高;氨氮组黄颡鱼肝脏中硫代巴比妥酸反应物的过度积累表明,应激产生的大量自由基并不能被机体自身的抗氧化酶体系完全清除;亚致死浓度的慢性氨氮胁迫会对黄颡鱼幼鱼的免疫应答体系造成抑制. 相似文献
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Airlift pumps are commonly used in aquaculture systems to circulate water and maintain critical gas levels. In production marine reuse systems, a significant decrease in airlift pump flowrate was visually observed immediately after feeding. In experimental systems without fish, it was found that feed additions of less than 10 mg/L decreased water flow by as much as 78% for diffuser injectors but only 10% for pumps with direct air injection. For both injector types, feed impact diminished over several hours but persisted longer in seawater than in freshwater. Video footage revealed increasing bubble coalescence with the addition of feed. The decrease in pump flow is likely attributed to water property changes due to compounds leaching out of the feed. This decrease in pumping rate has the potential to negatively impact water quality, system performance, and fish health. 相似文献
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Effects of filleting method,stress, storage and season on the quality of farmed Atlantic cod (Gadus morhua L.) 
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下载免费PDF全文 Gaute Jørpeland Albert Imsland Lars Helge Stien Hogne Bleie Bjorn Roth 《Aquaculture Research》2015,46(7):1597-1607
The effects of filleting method, pre‐slaughter stress, storage and season on drip loss, water content, water‐holding capacity, rigour contraction and colour in Atlantic cod, Gadus morhua L., were examined. A total of 182 fish were sampled under commercial conditions. To test the effects of filleting method and stress, stressed (S) and unstressed (C) fish were filleted either pre (Pr) or post rigour (Po) at 1 and 48 h post mortem, receptively. The muscle pH significantly decreased from 0 to 144 h of storage in all groups. The onset of the rigour contraction was more pronounced in the Pr‐S group as compared with the Pr‐C group, but after 144 h of storage, no difference in degree of contraction was observed. Filleting method, stress and storage time influenced the colour of the fillets. Post‐rigour filleting caused a significantly increased in measured Lightness (L*) during storage. Stress caused a significant increase in measured redness (a*). No significant difference was found for water‐holding capacity. The water content was influenced by filleting method, where the Pr‐S group had a significantly lower water content compared with the Pr‐C groups; water content changed also according to season. The findings of this study show that stress, filleting method, time of storage and season had a significant effect on the drip loss, where a combination of all factors will determine the total loss. 相似文献
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Yukiko Maruji Momoko Shimizu Michiyo Murata Masashi Ando Morihiko Sakaguchi Takashi Hirata 《Fisheries Science》2010,76(3):521-528
Boiled muscle extracts obtained from yellowtail Seriola quinqueradiata and bastard halibut Paralichthys olivaceus were treated with two kinds of purified enzymes (acid phosphatase and glutamate decarboxylase), and the change in contents
of nucleotides, related compounds, and free amino acids was examined. The change in taste qualities was also investigated
by a taste test. The enzyme treatment resulted in a marked decrease in the contents of such umami substances as inosine 5′-monophosphate
(IMP) and glutamic acid (Glu). The taste test revealed that the treatment of these fish muscle extracts with both or either
of the enzymes caused a sharp decrease in umami intensity and also an increase in sourness but not a change in pH. The treatment
also effected marked decreases in thickness and overall taste intensity. These findings suggest that IMP and Glu function
not only to intensify the thickness and overall taste as well as the umami, but also to repress the sourness sensation elicited
by the fish muscle extracts. 相似文献
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L. J. BAUMGARTNER N. K. REYNOLDSON L. CAMERON J. G. STANGER 《Fisheries Management and Ecology》2009,16(6):429-437
Abstract The total number and condition of fish extracted via high and low flow irrigation pumps was assessed over a 2-year period in the Namoi River, Australia. A combination of boat electric fishing and fyke netting was used for 10 weeks during the peak irrigation period to determine species and size classes susceptible to entrainment during water abstraction. Over 2300 fish passed through the pump outlets over the study period, with many individuals (7.5% of total) both killed and injured. The maximum number of fish entrained in a single day was 232. Mortality was significantly higher from the high volume pump site, but only large (>200 mm long) or small (<50 mm long) fish were killed. Medium-sized fish (50–200 mm long) largely survived the abstraction process; although 70 were injured (3% of total), only one was killed (0.07%). The Electric fishing surveys showed that only four species were present in storage dams, suggesting that survival through the pump systems may be size and species specific. Fish that survived the water abstraction process had no opportunities to return to the main river system and were effectively classified as lost from the main river population. The development of suitable mitigation measures, including operational changes and screening, are suggested as mechanisms to prevent extraction and minimise any adverse impacts arising from irrigation development. 相似文献
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Abstract Salmonid fishways have been used in many countries for non-salmonid fishes, including Australia, but generally with poor results. Trapping the entrance and exit of a 1:9 gradient salmonid fishway on the Murray River confirmed very poor passage of native fish, with <1% of the most abundant species ascending. Fifty years of fish passage monitoring showed the numbers of three native species declining by 95–100% and non-native fish becoming dominant. Fishways are now being designed for native fish and being quantitatively assessed, but daily flow management also needs to be addressed. The ecological model for passage of potamodromous fishes has changed from passing adults of a few species to one that incorporates the whole fish community, specifically: immature fish of large-bodied species that dominate numbers migrating upstream; a diverse range of movement strategies; and small-bodied species, crustaceans and low numbers of less-mobile species. 相似文献
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研究鱼类对反击式水轮机流道内压力突变的响应,为水电站水轮机的结构优化和生态运行提供技术支撑。实验鱼为四大家鱼1龄幼鱼,体长(100±10)mm、体宽(6±2)mm,鱼体健康、鱼鳞完整;实验装置由变频真空泵、高压舱、压力表、连接气管、高速摄像机组成。对四大家鱼幼鱼分别进行负压承受实验(预设压力值分别为80、60、40、20 kPa)、循环负压承受实验(预设压力值分别为80、60、40、20 kPa)和压力梯度承受实验(预设压力值分别为40、20 kPa),测试鱼的行为状态和损伤状况;实验结束后,实验鱼被分别移入暂养水槽暂养,并观察记录其实验后1、4和12 h的自愈状态;最后解剖实验鱼,观察和记录其脏器损伤状态。结果表明:(1)四大家鱼幼鱼对水体中的压力陡降具有较强的敏感性,出现损伤主要发生在第1次压力陡降过程,损伤程度与最小压力值及压力变化梯度成正相关,负压循环次数的增加不会增加家鱼幼鱼受压力损伤的程度和死亡率;(2)压力最低值和压力梯度是家鱼幼鱼通过水轮机流道下行受到压力损伤的主要原因,随着压力最低值的降低和压力梯度的增大,家鱼幼鱼损伤的程度和死亡率上升;(3)生活在河流中底层的青鱼和草鱼对负压和压力梯度较生活在河流中上层鲢和鳙具有更好的耐受性,在进入水轮机流道前鱼类适应压力状态与鱼体通过水轮机受到压力损伤具有一定的相关性;(4)四大家鱼幼鱼受到压力损伤的阈值为20 kPa,当压力值小于或等于损伤阈值,家鱼幼鱼受到压力损伤。 相似文献