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1.
哇,海洋馆     
近些年到国内各地的旅游者不难发现,各具特色的海洋馆、水族馆渐显成为一条新的“风景线”,尤其是孩子们,均为海洋馆丰富的海洋动物所迷,留连忘返。  相似文献   

2.
提出以2,6-二氯苯胺为原料,经重氮化、氟硼酸重氮盐热分解、硝化、氟化等步骤,制成2,3,4-三氟硝基苯。优点是工艺简单,收率较高.  相似文献   

3.
2005年10月-12月,对长江口北部和江苏南部海域进行了较为全面的沉积物化学调查,调查海域范围较广、布点密度较高,为全面深入地研究该海域的底质分布状况积累了重要的资料.分析研究了其中的表层沉积物中重金属Cu,Zn,Pb,Cr含量的分布特征;讨论了重金属与有机质的相关性,并以有机质含量作为环境因素的校正因子,判别了异常值;Cu,Zn,Pb的含量相互之间也呈明显正相关,除了由于三者有相似的地球化学性质之外,可能表明它们在本调查海域有相似的污染源.以平均富集因子对重金属的富集状况进行了评价,结果表明Cu为中度污染,Zn,Pb,Cr均为轻度污染,重金属的富集程度Cu>Zn>Cr>Pb.  相似文献   

4.
胡声 《海洋世界》2001,(6):28-28
水母何物?一种生活在水中游动的腔肠动物。种类虽多,但可分两大类,水媳水母和钵水母。水媳水母生活在淡水中,个体较小,身体透明。钵水母生活在海洋里,个体大,身体也透明,水母有两种繁殖方式;即有营裂体的无性生殖(附着水媳体,钵形,构造接近海葵)和雌雄交配的有性生殖(游泳的水母体伞形,由其内胚层产生生殖细胞)。性成熟的水母,开始产卵,  相似文献   

5.
工业革命经过数十年的发展,沉睡地下数亿年的煤炭、石油被粗暴地唤醒,形成滚滚的黑烟消融在本是甜丝丝的空气中,机械吐出海量的美元与英镑,人类的机械式社会发展到达顶峰。  相似文献   

6.
是的,这有什么大惊小怪的昵!没有了海上的客船,对于从上海到宁波的旅客来说,还有更多、更便捷的选择,他们可以选择高速公路,可以选择飞机,起码还有可以选择提了速的火车——这就是市场竞争的法则:“快”淘汰了“慢”!  相似文献   

7.
唐山是一座有百年历史的重工业城市,因市区中部的大城山(原名唐山)而得名。  相似文献   

8.
思源 《海洋世界》2004,(11):10-11,13
2004国庆黄金周简报 国庆节结束了,您按时回去上班了吗?上班的时候,您回过神儿来了吗?脑子里是否还放映着某处美景的实况?或许,您在抱怨着再也不想在“黄金周”期间出外旅游?就是没有出去的,到石景山游乐园玩玩吧,一个10秒钟的游戏,排队用了1个小时。所以,您得理解一个相貌斯文的女孩子会站在过山车的排队处歇斯底里地大骂。  相似文献   

9.
继往开来,团结奋进,争创一流──庆祝青岛海洋大学建校70周年校长管华诗在党的十四大和四中全会精神指引下,正当海洋大学广大师生认真学习、贯彻《中国教育改革和发展纲要》及第四次全国高教工作会议精神,争取实施"211工程"宏伟蓝图的时候,我们迎来了建校70...  相似文献   

10.
《海洋世界》2009,(4):9-9
发热的地球已经让越来越多的生物待不下去了。最近,一项新研究表明随着全球日益变暖,热带陆生冷血动物(如蜥蜴)的生存出现了危机。冷血动物无法像恒温动物那样自行调节体温,其体温完全取决于外界环境。它们的适宜生存温度为20~40℃,超过40℃即为过热。研究者表示,使冷血动物陷入困境的不光是温度问题,过多的日光照射是更为重要的原因。在热带地区,荫凉处对冷血动物的生存至关重要,在那里它们可躲避目光的直接照射。但随着茂密的热带雨林被人类改造为耕地和草场,冷血动物失去了天然庇佑。  相似文献   

11.
The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ~200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ~380 km from the coast at a depth of ~250 m above the sea level.  相似文献   

12.
We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative abundances of organic and inorganic carbon as an index of the carbon cycle stability.  相似文献   

13.
We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic regime of the sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

14.
双壳贝类血淋巴中儿茶酚胺的检测方法初步研究   总被引:1,自引:0,他引:1  
研究的目的是探索一种检测双壳贝类血淋巴中儿茶酚胺含量的方法。以栉孔扇贝(Chlamysfarreri)和长牡蛎(Crassostreagigas)为实验对象,研究了取样、抗氧化剂、氧化铝用量以及Tris缓冲液用量等对实验结果的影响。结果表明,高效液相色谱电化学检测器法(HPLC-ECD)可以灵敏高效地对双壳贝类血淋巴中儿茶酚胺进行定性、定量检测。实验表明,取样时间最长不超过1.5min;还原性谷胱甘肽作抗氧化剂效果较好;前处理各试剂与血样量的最适配比为血样量1.5mL,Tris缓冲液(1.5mol/L,pH8.6)1mL和氧化铝25mg;水洗后离心并尽可能吸干氧化铝中的水分。去甲肾上腺素、肾上腺素和多巴胺的回收率分别为53%~69%、47%~73%和48%~56%。  相似文献   

15.
为研究黄河入海径流变化条件下河口附近海域盐度扩散特征,以更好地保护河口海域生物资源多样性,本文以黄河下游利津水文站的长序列实测径流数据资料为基础,利用近海水动力模型FVCOM,分析径流变化对黄河口海域盐度的影响规律。结果表明:黄河口与莱州湾之间存在顺时针的环流系统,在余流作用以及涨落潮方向的影响下,黄河冲淡水长期向莱州湾扩散;丰水期黄河冲淡水几乎影响了整个莱州湾,27盐度锋可以到达莱州湾中部,27等盐线的表层包络面积为2 665.61 km2,占莱州湾的1/4左右,枯水期低盐度水只有向南扩散的趋势,27以下的低盐度水集中分布在黄河口门附近,27等盐线的表层包络面积只有199.65 km2;5月份,随着入海径流量增加,27等盐线扩散的范围、距离、方向都会发生明显变化。在对近海生物资源有迫切保护需求的情景下,适当减少其他用水户供水量以增加入海生态径流量,可以有效改善黄河口海域附近的盐度情况,为生物资源的生长繁殖创造良好条件。  相似文献   

16.
We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the shelf zone and open sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

17.
The authors have previously determined that the effectiveness and failure pattern of the ice cover caused by flexural-gravity waves generated by a submerged body motion near the bottom ice can greatly depend on the depth of the water area. In its turn, the presence of a ledge on the ice surface may affect a wave propagation pattern. This paper presents an experimental study of the bottom contour influence on the deflection and length of flexural-gravity waves. The authors describe a numerical model for the analysis of the deformed state of ice caused by hydrodynamic loads due to a submarine motion, taking into account the bottom contour. The experiments are carried out in the ice tank. The results of calculations and experiments are compared.  相似文献   

18.
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state.  相似文献   

19.
Ten years of semistationary studies of the interaction of the ice cover and the coastal relief of the Kandalakhsa Gulf in the White Sea allowed us to reveal the peculiarities of these processes in the warm and cold years and the mechanisms of the origination of ice forms, including ice tents, which govern the character of the tidal flats. Three dynamic fast ice zones are distinguished by their geomorphological location, morphology, and ice dynamics. The dependence of the mechanisms and volumes of the enrichment of the fast ice in the sediments on the coastal zone??s relief was established. At the coast of the Kindo Peninsula (Velikaya Salma Strait), the ice mostly contains fine-sandy sediments. Coarser sediments, including boulders, are occasional and frozen into the ice at the contact of the fast ice and the bottom. At the expense of the ice??s spreading by 4?C6 times in the warm years and 2?C4 times in the cold years, several thousand tons of sediments mostly from the tidal flat??s surface (100?C700 m3 from 1 km of coast in the wide tidal flats and <50 m3 on the steep coasts) are delivered to the water area.  相似文献   

20.
北黄海海域大气湍流强度特征及风速标准差相似性分析   总被引:1,自引:1,他引:0  
根据国家海洋局"908"专项北黄海海区海洋气象观测资料,计算了2007~2008年间该海区4个不同季节的大气湍流强度并与其他海区及陆地下垫面大气湍流值相比较.北黄海海区大气湍流强度量级为10-2,比陆地下垫面大气湍流强度低一个量级.由于海洋的特殊性质,对秋季大气湍流强度日变化的分析发现,在大气湍流强度的影响因素中,海洋的热力作用相对较大.对水平方向风速标准差是否满足Monin-Obukhov相似关系进行了探讨,数据显示,在不稳定层结下冬季水平方向无量纲风速标准差与Z/L的关系,基本满足1/3次方律.秋冬在不稳定层结下垂直方向风速标准差满足Monin-Obukhov相似理论.  相似文献   

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