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151.
Coastal areas of the world are under treat due to the conflicting requirements of functions such as habitation and/or recreation, which affect the strategic asset of coastal scenery itself. Coastal managers, together with planners, need coastal landscape inventories, where the quality of coastal scenery is a part of the inventory. In order to provide an evidence-based approach for sound coastal management decisions, [Ergin et al., 2004] and [Ergin et al., 2006] developed a novel technique ‘coastal scenic evaluation’ (CSE), which addresses the evaluation of coastal scenery. The CSE technique utilizes fuzzy logic to derive values obtained from a checklist of 26 physical and human parameters. The methodology enables the calculation of an evaluation index (D), which categorizes the scenic values of coastal sites into five distinct classes. Using this technique, coastal scenic evaluations were carried out at 34 selected sites on the Western Black Sea coast of Turkey. Based on the calculated D values, a five-class differentiation was obtained for the selected sites, to provide baseline information for any envisaged subsequent management plans for these areas.  相似文献   
152.
彭坤  明辰  叶祥熙  张文献  庄军  宁西京 《海洋学报》2010,32(10):7245-7251
2009年我们建立了一个凝结势模型用以预测材料形成单晶体的能力,表明单元体材料(Ni,Al,Cu,Ar,Mg)的结晶能力随凝结势的增大而单调增强.本文将凝结势模型应用于二元材料体系,并结合分子动力学模拟研究了6% Al原子掺杂对于Ni单晶材料结晶能力的影响.模拟结果发现,Al元素的掺杂会大大减弱Ni单晶的结晶能力,在此基础上提出了二元材料体系凝结势的定义,表明凝结势模型可广泛应用于预测二元体材料的结晶能力.  相似文献   
153.
为科学地分析城市土地集约利用在空间上的分布规律及趋势,以玉溪市中心城区为研究区域,在玉溪市中心城区建设用地集约利用评价的基础上,通过空间相关分析的方法揭示了中心城区建设用地集约度的空间分布特征。结果表明:玉溪市中心城区集约利用度呈现出由城市中心逐渐向外递减的趋势,土地集约利用水平在一定程度上存在集聚效应;从全域空间分析看,各功能区土地利用集约度空间分布在整体上具有较好的正相关性,居住功能区相关性最强,其他功能区最弱;从局部空间的角度来看,集约度的分布既存在空间聚集性又存在空间异质性。  相似文献   
154.
Long term evolution of distant retrograde orbits in the Earth-Moon system   总被引:1,自引:0,他引:1  
This work studies the evolution of several Distant Retrograde Orbits (DROs) of varying size in the Earth-Moon system over durations up to tens of millennia. This analysis is relevant for missions requiring a completely hands off, long duration quarantine orbit, such as a Mars Sample Return mission or the Asteroid Redirect Mission. Four DROs are selected from four stable size regions and are propagated for up to 30,000 years with an integrator that uses extended precision arithmetic techniques and a high fidelity dynamical model. The evolution of the orbit’s size, shape, orientation, period, out-of-plane amplitude, and Jacobi constant are tracked. It has been found that small DROs, with minor axis amplitudes of approximately 45,000 km or less decay in size and period largely due to the Moon’s solid tides. Larger DROs (62,000 km and up) are more influenced by the gravity of bodies external to the Earth-Moon system, and remain bound to the Moon for significantly less time.  相似文献   
155.
Fish skin collagen hydrolysates (FSCH) were prepared from walleye pollock (Theragra chalcogramma) using a mixture of enzymes, namely trypsin and flavourzyme. The degree of hydrolysis of the skin collagen was 27.3%. FSCH was mainly composed of low-molecular-weight peptides and the relative proportion of <1000Da fraction was 70.6%. Free radical and oxygen species scavenging activities of FSCH were investigated in four model systems, including diphenylpicrylhy-drazyl radical (DPPH), superoxide anion radical, hydroxyl radical and hydrogen peroxide model, and compared with that of a native antioxidant, reduced glutathione (GSH). FSCH was also evaluated by water-absorbing and water-holding capacity. The results showed that FSCH was able to scavenge free radical and oxygen species significantly and to enhance water-absorbing and water-holding capacity remarkably. Therefore, FSCH may have potential applications in the medicine and food industries.  相似文献   
156.
In order to select an optimum extraction method for the target glycoprotein (TGP) from jellyfish (Rhopilema esculentum) oral-arms, a high performance liquid chromatography (HPLC)-assay for the determination of the TGP was developed. Purified target glycoprotein was taken as a standard glycoprotein. The results showed that the calibration curves for peak area plotted against concentration for TGP were linear (r = 0.9984, y = 4.5895x+47.601) over concentrations ranging from 50 to 400 mgL-1. The mean extraction recovery was 97.84% (CV2.60%). The fractions containing TGP were isolated from jellyfish (R. esculentum) oral-arms by four extraction methods: 1) water extraction (WE), 2) phosphate buffer solution (PBS) extraction (PE), 3) ultrasound-assisted water extraction (UA-WE), 4) ultrasound-assisted PBS extraction (UA-PE). The lyophilized extract was dissolved in Milli-Q water and analyzed directly on a short TSK-GEL G4000PWXL (7.8 mm×300 mm) column. Our results indicated that the UA-PE method was the optimum extraction method selected by HPLC.  相似文献   
157.
Sandu Bay is located in the East China Sea and is characterized by high-density fish farming and kelp culture. Despite this, little is known about the impacts of these different mariculture practices on the local environment. We investigated the temporal variation in macrobenthos and environmental conditions at three sites in the bay (fish farming site, kelp culture site, and a control site). We collected water and sediment samples during nine cruises between May 2009 and February 2010. The density of macrobenthos peaked at the fish farming site in July (655 ind./m2) whereas density did not fluctuate as widely at the other two sites. Biomass varied significantly at both the control and kelp culture sites, but had only a single peak at the fish farming site in June (21.90 g/m2). The dominant species varied throughout the study period at the control and kelp culture sites, whereas a single terebellid species (Lysilla pacifica) dominated the macrobenthos at the fish farming site. The diversity index H’ increased at the control site beginning in February then decreased after May, whereas H’ was low at the other sites in December. The mean dissolved oxygen level was highest at the control site (6.59 mg/L) and lowest at the fish farming site (5.54 mg/L). DO levels were lowest at all sites in summer (July and August). The sediment acid volatile sulfide content was higher at the fish farming site (1.46 mg/g dry weight) than those at the kelp culture and control sites (1.22 and 0.14 mg/g, respectively). Our results suggest that mariculture practices have a clear impact on the benthic environment/ community in Sandu Bay.  相似文献   
158.
The reclamation and utilization of debris flow waste-shoal land plays an important role in the mitigation and control of debris flow hazards, which thus contributes a lot to the exploitation of insufficient land resources in mountainous areas and the reduction of losses caused by debris flow. The aim of this paper is to discuss the features and mechanism of soil evolution of debris flow waste-shoal land so as to search for the available modes of its reclamation and utilization. The Jiangjiagou Ravine, a typical debris flow ravine, was selected to study soil evolution features of debris flow waste-shoal land based on the analysis of soil physieochemical properties and soil microstructure. It was found that the soil evolution rates of debris flow waste-shoal land varied with different modes of reclamation. For the land which had been reclaimed for less than lO years, soil evolved most rapidly in paddy fields, and more rapidly in dry farmland than in naturally restored waste-shoal land. For the land which had been used for more than lo years, the soil evolution rates of dry farmland, naturally restored waste-shoal land and paddy farmland decreased in the file. For the same utilization period of time, significant differences were recognized in soil evolution features under different modes of reclamation. Analysis data showed that soil clay content, soil thickness, the psephicity of skeleton particles and contents of microaggregates (〈0.02 mm) in paddy farmland were all highest. Soil nutrients and porosity of dry farmland were better than those of paddy farmland and naturally restored waste-shoal land, and those of paddy farmland were superior to those of naturally restored waste-shoal land. Paddy farmland characterized by rapid pedogenesis, stable evolution and high utilizability was the priority candidate for the reclamation and utilization of debris flow waste -shoal land.  相似文献   
159.
A large-scale bloom occurred from May to June in 2011 in sea area near Qinhuangdao of the Bohai Sea, leading to huge damage of the scallop culture industry. Similar blooms have been observed in this region for three years. The causative species of the bloom, which dominated the phytoplankton community with the maximum cell density around 109 cell/L, could not be identified with morphological features due to the small cell size (~2 mm). A pigment analytical method was then adopted to analyze the pigment profile of the phytoplankton samples collected from the blooming sea area. It was found that pico-sized (<2 mm), nano-sized (2-20 mm), and bulk phytoplankton samples had similar pigment profile, representing the pigment signature of the bloom-causative species. The major pigments detected included 19-butanoyloxyfucoxanthin (But-fuco), fucoxanthin (Fuco), diadinoxanthin (Diad) and chlorophyll a (Chl a), and high content of But-fuco was the most significant characteristics of the phytoplankton samples. Based on the pigment composition and content, the bloom-causative species could be tentatively identified as pelagophyte, "type 8" group of haptophyte, or silicoflagellate. Some unique features of the bloom, such as the extremely high cell density, small-sized and But-fuco containing cells, occurring in early summer, and the feeding-cessation effects on scallops, suggest it be a "brown tide" event similar to those reported in the east coast of the United States of America. The recurrent "brown tide" events and their dramatic impacts on the shellfish mariculture industry in Qinhuangdao need close attention in the coming years.  相似文献   
160.
1 INTRODUCTIONTherecentandfuturedevelopmentofspacebasedremotesensingtechnologyhasbroughtareformationtoresearchworkaswellasformulatingsuitablepolicyforpopulation,resources,environmentanddevelopment.Throughrealtimeandperiodicobservationsofalargear…  相似文献   
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