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进口ＰＣ－Ｅ５００之概况曹来发（华北电力设计院）ＳＨＡＲＰＰＣ－１５００机自１９８２年初问世以来，型号已发展为ＰＣ－１２００系列、ＰＣ－１３００系列、ＰＣ－１４００系列；１９８６年开始，日本ＳＨＡＲＰ公司推出了多ＣＰＵ的ＰＣ－１６００和ＰＣ－１６００... 相似文献
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实验比较新型虾保鲜剂（ＰＰＲ—１）及其它类型的虾保鲜剂如亚硫酸氢钠（ＳＢＳ）、植酸（ＰＡ）及日本虾保鲜剂（ＪＰＲ）对中国对虾ＰｅｎａｅｕｓＣｈｉｎｅｎｓｉｓ的保鲜作用。实验指出：（１）在冷藏（４℃）与冷冻（－１８℃）保藏条件下，ＰＰＲ—１及ＪＰＲ对中国对虾的保鲜效果均优于ＰＡ和ＳＢＳ；（２）在冷藏（４℃）或冷冻（－１８℃）条件下，去头保鲜效果均优于带头保鲜效果。 相似文献
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研究海脉冲营养素“ＨＭＣ”对小鼠免疫功能的影响。结果表明：小鼠口服ＨＭＣ３００ｍｇ／ｋｇ·ｄ，连续７～１０ｄ，可增加小鼠免疫器官的重量（Ｐ＜０．０５）；提高小鼠腹腔巨噬细胞吞噬率和吞噬指数（Ｐ＜０．０１）；促进ＰＨＡ刺激的淋巴细胞转化反应（Ｐ＜０．０１）和提高ＡＮＡＥ＋淋巴细胞百分率（Ｐ＜０．０５）；对小鼠血清溶血素和ＰＦＣ数目的生成无显著影响（Ｐ＞０．０５），对ＨＰＡ和ＣＴＸ引起的免疫抑制有拮抗作用。提示：ＨＭＣ是一种有效的免疫调节剂。 相似文献
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本文是挪威ＯＣＥＡＮＯＲ公司１９９５年５月２日编写的《ＳＥＡＷＡＴＣＨ气象／海洋资料浮标》（ＴｈｅＳＥＡＷＡＴＣＨＭｅｔｏｃｅａｎＤａｔａＢｕｏｙ）中的两节。文章详细介绍了最近十年国外测波浮标试验的若干情况，对我国测波浮标的研制和使用有所启发。现译出，供参考。文章标题系译者所加。 相似文献
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７０年代初，全球气候问题开始成为举世瞩目的大事，而且人们已逐渐认识到海洋在全球气候系统中的重要性。因此，海气相互作用对气候形成及演变作用的研究获得了巨大发展。如，７０年代末美国开始的“赤道东太平洋环流研究”（ＥＰＯＣＳ：１９７８年至今）、“太平洋赤道动力学”（ＰＥＱＵＡＤ）、“热带热量”（Ｔｒｏｐｉ－ｃａｌＨｅａｔ）、“第一次全球大气实验”（ＦＧＧＥ）以及现在还在进行的国际计划“热带海洋与全球大气”（ＴＯＧＡ；１９８５～１９９４）、“世界大洋环流实验”（ＷＯＣＥ：１９９０～２０００）和世界各国或… 相似文献
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１９９８年３月 ,深１１５０ｍ的气水合物研究井（ＪＮＯＣ／ＪＡＰＥＸ／ＧＳＣ马立克２Ｌ -３８井）在加拿大西北地区麦肯齐三角洲东北边缘完钻。该项目使北美和日本的研究者一起率先对极地气水合物矿藏进行了研究 ,包括专用加长岩心和相关工程与科学研究。众所周知 ,在许多极地盆地中天然气水合物代表一种重要的油气储集层 ,可是在马立克２Ｌ -３８井之前几乎没有人从事油田研究以评价其原始特征。马立克２Ｌ -３８井项目确立了２个基本目标。日本国家石油公司（ＪＮＯＣ）、日本石油勘探公司（ＪＡＰＥＸ）和来自日本的其它参与组织试图… 相似文献
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谈美国SonTek水文仪器公司声学多普勒测流仪器 总被引：2，自引：0，他引：2
本文简要介绍了美国 Ｓｏｎ Ｔｅｋ 水文仪器公司产品三大系列。（１） 声学多普勒水流剖面仪（ Ａ Ｄ Ｐ） 系列;（２） 声学多普勒水流计（ Ａ Ｄ Ｃ Ｍ） 系列;（３） 声学多普勒流速计（ Ａ Ｄ Ｖ） 系列。对产品的特点、技术性能指示及海上实验和应用也进行了描述。 相似文献
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大鹏湾几种赤潮甲藻的分类学研究 总被引：24，自引：3，他引：24
对采自深圳大鹏湾的５种赤潮甲藻进行了分类学研究。其中海洋原甲藻属ｐｒｏ－ｒｏｃｅｎｔｒｕｍ２种：Ｐ．ｍｉｃａｎｓ Ｅｈｒｅｎｂｅｒｇ，Ｐ．ｍｉｎｉｍｕｍ（Ｐａｖｉｌｌａｒｄ）Ｓｃｈｉｌｌｅｒ；亚历山大属Ａｌｅｘａｎｄｒｉｕｍ２种：Ａｔａｍａｒｅｎｓｅ（Ｌｅｂｏｕｒ）Ｂａｌｅｃｈ，Ａ．ｃａｔｅｎｅｌｌａ（Ｗｈｅｄｏｎ＆Ｋｏｆｏｉｄ）Ｂａ－ｌｅｃｈ；施克里普藻属Ｓｃｒｉｐｐｓｉｅｌｌａ１种：Ｓ．ｔｒｏ 相似文献
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超高分子量聚乙烯和高密度聚乙烯网线的拉伸力学性能比较研究 总被引：11，自引：0，他引：11
在标准实验室环境里，对超高分子量聚乙烯(UHMWPE)和高密度聚乙烯(HDPE)网线的拉伸力学性能进行了比较研究。结果表明：UHMWPE网线较HDPE网线具有较高的强度、拉伸模量和结强损失率；而HDPE网线较UHMWPE网线具有较高的断裂伸长率。结论可供渔具设计及网线材料选配时参考。 相似文献
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The East Sea, with an average depth of 1700 m, has long been subject to heavy fishing pressure, resulting in derelict fishing gear. Most derelict fishing gears, such as fishing nets, fishing ropes, and crab pots, sink to the seabed and do not degrade. This gear results in “ghost fishing,” which has adverse impacts on deep benthic habitats. Recently, the Korean government has started to remove derelict fishing gears from the deep seabed of the East Sea by bottom trawling with heavy hooks (50–80 kg) and ropes. A total of 207.8 and 252.2 tons of marine debris in 2009 and 2010, respectively, were removed from the seabed, most of which were derelict fishing gears. Contrary to monitoring surveys and clean-up in shallow waters, removal of marine debris from remote deep habitats is much more difficult and dangerous for removal crews. 相似文献
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Fuel consumption in fisheries is a primary concern because of its effects on the environment and the costs incurred by fishermen. Many studies have been conducted to reduce the fuel consumption in fishing operations. Fuel consumption due to fishing gear during a fishing operation is generally related to the hydrodynamic resistance on the gear. This means that fuel consumption is proportional to the drag created by the towing speed. Based on numerical methods, this study suggests a new approach to reduce fuel consumption in fisheries. The results of the simulation are in good agreement with those of model experiments. The total as well as partial resistance forces on the gear are calculated by simulation. The simulation results suggest improved materials and gear structure for reducing the hydrodynamic forces on the gear while maintaining gear performance. The method for assessing the gear performance involves measuring the height and width of the net mouth. Furthermore, this study investigates the efficiency of a low-energy trawl from an economic point of view. The findings of this study will be useful in reducing greenhouse gas (GHG) emissions in fishing operations, and thereby contribute toward lowering fishing costs by saving fuel. 相似文献
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Robert Kilpatrick Graeme EwingTim Lamb Dirk WelsfordAndrew Constable 《Deep Sea Research Part I: Oceanographic Research Papers》2011,58(4):486-491
Studies of the interactions of demersal fishing gear with the benthic environment are needed in order to manage conservation of benthic habitats. There has been limited direct assessment of these interactions through deployment of cameras on commercial fishing gear especially on demersal longlines. A compact, autonomous deep-sea video system was designed and constructed by the Australian Antarctic Division (AAD) for deployment on commercial fishing gear to observe interactions with benthos in the Southern Ocean finfish fisheries (targeting toothfish, Dissostichus spp). The Benthic Impacts Camera System (BICS) is capable of withstanding depths to 2500 m, has been successfully fitted to both longline and demersal trawl fishing gear, and is suitable for routine deployment by non-experts such as fisheries observers or crew. The system is entirely autonomous, robust, compact, easy to operate, and has minimal effect on the performance of the fishing gear it is attached to. To date, the system has successfully captured footage that demonstrates the interactions between demersal fishing gear and the benthos during routine commercial operations. It provides the first footage demonstrating the nature of the interaction between demersal longlines and benthic habitats in the Southern Ocean, as well as showing potential as a tool for rapidly assessing habitat types and presence of mobile biota such as krill (Euphausia superba). 相似文献
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Overcapacity in the fishing fleets is considered as the most serious threat to sustainable fisheries. More effective fishing vessels and catching gear contribute to increased catch capacity. Increased catch capacity causes environmental problems such as overexploitation and calls for larger quotas. The problem of overcapacity indicates the need for a stronger integration of technological aspects into fisheries management. This article assesses the differences in sustainability between the Norwegian ocean and coastal fishing fleets in the cod fisheries, by using systems engineering methods. Attributes of sustainability in the Norwegian cod fishing fleets are investigated, as well as acceptance criteria and performance indicators. The results show that there are huge differences in the performance between the vessel groups, and that the results of an evaluation of sustainability in the fishing fleets are dependent on which attributes are explored. Thus, the discussion may contribute to a better decision basis and improved sustainability in fisheries management. 相似文献
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The aim of this paper is to compare the criteria for eco-labeling of wild-caught fish in the Norwegian eco-certified fisheries, and to study if these eco-labels affect the harvesting patterns of Norwegian fishermen. The eco-labels Marine Stewardship Council (MSC), KRAV and Friend of the Sea (FOS) as applied in 2009 were studied. In this study, the harvesting patterns are defined by using the following parameters: season, catch area, size of fishing vessel, gear type, bycatch, location of landing site and distance to the fishing ground. KRAV had more specific criteria than did MSC and FOS in specific fisheries regarding time of the fishing effort, catch area, size of fishing vessels, gear type (e.g. hook size, and the use of beam trawlers was not permitted) and distance to the fishing ground. The findings show that few of the eco-label requirements influenced these aspects in Norwegian fisheries. 相似文献
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《Marine Policy》2014
This study examined the perceptions of fishers from two fishing communities with differing use histories and involvement in the long-standing (16 yr) multiple use Mafia Island marine protected area (MIMP), Tanzania. A randomly distributed questionnaire indicated that 94% of fishers believed that without the MIMP, there would be overfishing, dynamite use, destroyed habitats, and few fish. Fishers were more positive about core zones (no-take fishery closures) than general use zones (areas allowing selective fishing) as a consequence of increases in fishing pressure. Those that reported increased catches and sizes of fish since the creation of the MIMP were more likely to agree with present zone locations and more positive in general about fisheries and conservation planning. Most thought that fish size and gear restrictions were preferable to permanent closures. Perceptions differed among communities and gear users. Community and gear type explained 46% of the variance in responses about the perception that fisheries and conservation are compatible goals. Somewhat surprisingly, these effects were more important than catch increases or involvement in MIMP-related activities. The differences in perception between communities may be partly attributed to different fishing histories. Multiple-use zoning provides a means to identify and resolve conflicts and achieve what are likely universal objectives for fisheries sustainability and conservation. 相似文献
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In this paper we review levels of net loss, what happens to the gear once it has been lost, and the resulting levels of ‘ghost catches’ made in passive net fisheries in the EU. We also consider ghost catches resulting from lost gear in other types of fisheries, and the extent to which the value of ghost catches has been quantified. We consider why fishing gear is lost, and profile common management responses. We present a cost benefit model to assess the relative cost effectiveness of different management measures, and suggest that gear retrieval programmes may provide less value for money than other management responses. 相似文献
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Overexploitation of bycatch and target species in marine capture fisheries is the most widespread and direct driver of change and loss of global marine biodiversity. Bycatch in purse seine and pelagic longline tuna fisheries, the two primary gear types for catching tunas, is a primary mortality source of some populations of seabirds, sea turtles, marine mammals and sharks. Bycatch of juvenile tunas and unmarketable species and sizes of other fish in purse seine fisheries, and juvenile swordfish in longline fisheries, contributes to the overexploitation of some stocks, and is an allocation issue. There has been substantial progress in identifying gear technology solutions to seabird and sea turtle bycatch on longlines and to direct dolphin mortality in purse seines. Given sufficient investment, gear technology solutions are probably feasible for the remaining bycatch problems. More comprehensive consideration across species groups is needed to identify conflicts as well as mutual benefits from mitigation methods. Fishery-specific bycatch assessments are necessary to determine the efficacy, economic viability, practicality and safety of alternative mitigation methods. While support for gear technology research and development has generally been strong, political will to achieve broad uptake of best practices has been lacking. The five Regional Fisheries Management Organizations have achieved mixed progress mitigating bycatch. Large gaps remain in both knowledge of ecological risks and governance of bycatch. Most binding conservation and management measures fall short of gear technology best practice. A lack of performance standards, in combination with an inadequate observer coverage for all but large Pacific purse seiners, and incomplete data collection, hinders assessing measures' efficacy. Compliance is probably low due to inadequate surveillance and enforcement. Illegal, unreported and unregulated tuna fishing hampers governance efforts. Replacing consensus-based decision-making and eliminating opt-out provisions would help. Instituting rights-based management measures could elicit improved bycatch mitigation practices. While gradual improvements in an international governance of bycatch can be expected, market-based mechanisms, including retailers and their suppliers working with fisheries to gradually improve practices and governance, promise to be expeditious and effective. 相似文献