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1.
船舶压载水携带的外来入侵性海洋物种对全球海洋生物多样性和生态系统环境造成巨大危害.探讨处理船舶压载水的方法和技术的优缺点,防治船舶压载水带来的海洋生物入侵和传播,保护海洋环境.  相似文献   

2.
概述了船舶压载水携带有害水生物和病原体破坏海洋生态环境及危害公众健康问题,介绍了防止压载水污染的各种压载水处理技术措施.根据厦门港面临的船舶压载水污染威胁,提出了制定有效的压载水管理条例、加强执法人员培训等应对措施.  相似文献   

3.
近几年来,船舶压载水的危害越来越受到各界的关注,国际海事组织积极跟进,先后通过决议和公约的形式为船舶压载水的控制和管理提供操作指南.分析现有的主要船舶压载水处理方法,并对比其优缺点.  相似文献   

4.
船舶压载水导致的生物入侵及其防治对策   总被引:2,自引:0,他引:2  
国际航运船舶,尤其是船舶装载的压载水是传播地理性隔离有害生物的主要途径,这类传播目前已经在世界范围内对生态环境和世界经济造成了巨大的危害.该文介绍了国际航运船舶压载水情况,压载水所携带生物种类,以及可能入侵的风险和危害.总结了目前已经应用和正在研究中的各种处理压载水的方法,提出了使用风险评估系统与动态生态模型相结合,应用计算机和数学的定量分析手段的必要性和重要性.以期对压载水的生物入侵可能造成的风险和危害给出定性乃至定量的评价,为我国压载水处理和生物入侵的综合防治提供参考.  相似文献   

5.
船舶压载水是有害生物入侵的主要途径之一[1].国际海事组织已采取多种措施来控制和减少有害生物通过压载水的船舶入侵,包括全球压载水计划和2004年2月13日实施的国际船舶压载水控制和管理公约.介绍几种被证明有效的压载水处理技术,并对这些技术做一些简单对比.  相似文献   

6.
外来生物的入侵对生态环境、人类健康及经济发展带来了巨大的负面影响.控制船舶压载水的排放以及研究较为有效的压载水治理方法是解决外来物种通过压载水入侵的有效途径.对目前正在使用的或正在研究中的船舶压载水处理技术等进行比较详细地阐述,分析各种方法的利弊,提出最有效可行的压载水处理方法.  相似文献   

7.
近年来国际航运界意识到船舶压载水导致的外来生物入侵对环境、人类健康及经济发展带来了巨大的影响.为此发展多样的能够有效解决外来物种通过压载水入侵的技术是国际航运界的共同目标.介绍目前主要压载水处理技术,分析国际海事组织制定的压载水公约未生效的原因.  相似文献   

8.
船舶压载水引发的生物入侵问题日益严重。通过对浮游生物典型检测方法的分析,对比了不同压载水检测方法的技术特点。基于不同使用环境下压载水检测要求,阐述了不同环境因素下选择压载水检测形式的方法和原则。结合目前船舶压载水检测的形势和需求,展望了压载水检测方法的发展趋势。建议今后实践应用中需要根据压载水类型和处理要求灵活选择检测手段,尤其是以数字全息技术为代表的原位检测技术具有广阔的发展前景。  相似文献   

9.
船舶压载水异域排放已经威胁很多国家的海岸生态环境,人类的安全和健康。为了在船舶压载水排放前就对其中的微生物进行灭活处理,该文自制了水力超声空化装置,并研究其对船舶压载水中的典型藻类异弯藻的灭活效果,探讨了超声波脉冲时间对灭活效果的影响。经研究表明,超声波能和水力空化协同作用,在离心泵频率为35Hz,作用60min之后,超声波脉冲时间为5s和8s的灭活效果较好,灭活率分别达到68.83%和68.52%。该技术在压载水处理领域有很好的应用前景。把该技术实际用于处理现实生活中大规模的压载水,还需要进一步研究。  相似文献   

10.
原生海水模拟船舶压载水的电解试验   总被引:3,自引:1,他引:2  
用原生海水模拟船舶压载水进行了电解处理的试验研究,直接电解处理船舶压载水,以4.0 mg/L初始余氯处理, 能杀灭99.99%的细菌和72%的藻类及部分原生动物;理论计算证明, 通过直接电解以5.0 mg/L初始余氯处理1 000 m3船舶压载水交流电耗仅为35 kW*h. 并还提出了解决腐蚀问题的两种方案,即压载时处理保持低余氯和充氮脱氧后排放时电解.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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