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51.
52.
以1,4—苯二酚和不同的短链脂肪酸为基本原料,经溴代、加成、形成酰卤和酰化等反应,合成了六种新的溴化脂肪酸—2,3,5,6—四溴—1,4—苯二酯。通过对产物的碳、氢、溴等元素的定量分析,以及红外吸收光谱和氢核磁共振谱的研究,验证了化合物的结构。 相似文献
53.
This paper presents a method to statistically predict the magnitude of impact pressure (including extreme values) produced by deep water waves breaking on a circular cylinder representing a column of an ocean structure. Breaking waves defined here are not those whose tops are blown off by the wind but those whose breaking is associated with steepness. The probability density function of wave period associated with breaking waves is derived for a specified wave spectrum, and then converted to the probability density function of impact pressure. Impacts caused by two different breaking conditions are considered; one is the impact associated with waves breaking in close proximity to the column, the other is an impact caused by waves approaching the column after they have broken. As an example of the application of the present method, numerical computations are carried out for a wave spectrum obtained from measured data in the North Atlantic. 相似文献
54.
Nowadays there are some chronic serious environmental problems, such as eutrophication, blue tide and so on, in a complicated coastal zone or a semi-enclosed bay, because the water exchanges between an inner bay and an outer sea is weak compared with the supply of contaminant. Under this situation, a method to improve the water quality by 3-dimensional small unsymmetrical structures has been proposed by Komatsu et al. In this paper, several numerical simulations of the tidal current and concentration for various arrangements of bottom roughness in a semi-enclosed model bay are carfled out with a depth-averaged 2-D numerical model. The model is solved by the hybrid finite analytic method with nonstaggered grid. And the SIMPLES algorithm with Rhie and Chow' s momentum interpolation technique is used for the simulation. The effect of Komatsu' s method for water purification is examined by numerical simulation. The result of numerical experiment indicates that it is possible to generate a new tidal residual current and to activate a tidal exchange by bottom roughness arrangement only. 相似文献
55.
Abstract. The temperate, symbiotic coral Cladocora caespitosa occurs naturally with variable numbers of zooxanthellae. This allows us to study differences in the physiology of symbiotic and "non-symbiotic" polyps and to correlate them with zooxanthellae activities.
Zooxanthellae density in "dark" (normal-colored) polyps was 50 times higher than in "white" (bleached) polyps.
The chlorophyll a content per zooxanthella was 3 times, and Chi c was 13 times higher in white polyps than in dark ones. O2 -flux experiments were conducted with colonies in situ and with single polyps - dark and white - under laboratory conditions. Two approaches were used to evaluate the contribution of zooxanthellae translocation products to animal respiration. Both revealed that the animal tissues derive a higher benefit from the zooxanthellae during periods of low water temperature than during warm periods. 相似文献
Zooxanthellae density in "dark" (normal-colored) polyps was 50 times higher than in "white" (bleached) polyps.
The chlorophyll a content per zooxanthella was 3 times, and Chi c was 13 times higher in white polyps than in dark ones. O
56.
本文对北部湾三维潮波进行了数值研究,并将所得结果与现有观测资料作了比较。通过比较发现两者相当一致。文中还绘制了M_2和K_1分潮的同潮图,并对其作了讨论。可以断定,北部湾的日潮优势是由日潮共振所引起的。M_2和K_1分潮流的水平分布表明,强流区位于它们各自的蜕化无潮点附近。还讨论了分潮流的铅直结构,可以看出这种结构十分接近实际分潮流场的特征。 相似文献
57.
北黄海沉积物——水界面反硝化速率及影响因素研究 总被引:4,自引:0,他引:4
探讨近海氮的循环机制,采用乙炔抑制法和现场静态箱法对北黄海夏季局部海域的反硝化速率进行了研究,该海域反硝化速率在2.5~5.8μmol/m2.h之间,平均4.85μmol/m2.h。影响其反硝化速率的主要因素为溶解氧,其次是温度。北黄海的反硝化速率低于珠江口和长江口海域。 相似文献
58.
Andrey Andreev Makio Honda Yuichiro Kumamoto Masashi Kusakabe Akihiko Murata 《Journal of Oceanography》2001,57(2):177-188
Excess CO2 and pHexcess showing an increase in dissolved inorganic carbon and a decrease in pH from the beginning of the industrial epoch (middle of the 19th century) until the present time have been calculated in the intermediate water layer of the northwestern Pacific and the Okhotsk Sea. It is concluded that: (1) The Kuril Basin (Okhotsk Sea) and the Bussol' Strait areas are characterized by the greatest concentrations of excess CO2 at isopycnal surfaces due to the processes of formation and transformation of intermediate water mass. (2) The largest difference in excess CO2 concentration between the Okhotsk Sea and the western subarctic Pacific (about 8 µmol/kg) is found at the = 27.0. (3) The difference in excess CO2 between the western subarctic Pacific and subtropical regions is significant only in the upper part of the intermediate water layer ( = 26.7–27.0). (4) About 10% of the excess CO2 accumulation in the subtropical north Pacific is determined by water exchange with the subarctic Pacific and the Okhotsk Sea. 相似文献
59.
在20×10~9Pa和25×10~9Pa条件下,对石榴石橄榄岩进行的14次高温高压熔融实验研究表明,在1600℃时石榴石橄榄岩开始熔融(初熔),熔体中的SiO_2>70%,Na_2O+K_2O>8%,类似于A型花岗岩成分。本实验为地幔花岗岩的成因提供了证据。 相似文献
60.
In this paper, the calculating charts and formulae about wave pressure on the breast wall are derived with seven parameters on the basis of physical model study. The verification shows that the charts agree with the example, and are adopted in the Specifications of Fishery Harbours Breakwater by the Ministry of Agricultures. 相似文献