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41.
预测和评价了青岛港液体化工码头苯贮罐苯泄漏对大气环境的影响.结果表明,苯罐一旦发生泄苯事故,会对大气环境造成不同程度的影响;在最不利天气条件下,泄漏挥发量为3375kg,会导致22人死亡;泄漏挥发量为1237kg,会导致4人死亡;如果同样的泄苯挥发量,发生在微风条件下,则分别有4人死亡和无人死亡;若发生33kg泄漏挥发量,无论在何种天气条件下,都不会导致人员伤亡。  相似文献   
42.
从典型患病栉孔扇贝(Chlamys farreri)体内分离到一株特殊微生物,光镜下可见的粒子为革兰氏染色阴性;电镜观察为圆形、近似圆形,已经发现的粒子大部分直径在300nm以下,最小为50nm左右,最大可达4000nm以上。该细菌在人工培养基上形不成肉眼可见的菌落,倒置显微镜下其菌落为无色透明、圆形、小点状菌落。生化特性测试表明该细菌能利用吐温-40与吐温-80。其分类地位尚待进一步分析和证实。  相似文献   
43.
Diel patterns in the chlorophyll a specific absorption coefficient of surface picoplankton, a*pico (γ) (m2·[mg chlorophyll a]−1), were studied at 7 stations under daily cycle of in situ light condition in the western subarctic Pacific and Japan Sea. All the data were normalized by dividing the anomaly with daily averaged a*pico (γ). Opposite diel patterns were observed for the normalized a*pico (443) and a*pico (675) with maximum toward dawn or dusk and minimum toward midday at 4 stations under low-irradiance (LI) conditions and vice versa at 3 stations under high-irradiance (HI) conditions. The absorption efficiency factors at red absorption peak, Q a (675), were determined by reconstruction with intracellular chlorophyll a concentration and cell diameter. The normalized Q a (675) also showed diel pattern with maximum toward midday and minimum toward dawn or dusk under LI. The diel pattern in a*pico (675) and Q a (675) were primarily caused by changes in intracellular chlorophyll a concentration due to photoadaptation under LI. The diel pattern in a*pico (443) was influenced by pigmentation, as recognized by blue to red ratio [a*pico (443)/a*pico (675)] under HI. This study proposed that the opposite diel pattern in a*pico (γ) might occur for a wide range of algal species. The results presented here have important consequences for the interpretation of diel variations in optical properties observed in the open ocean.  相似文献   
44.
尝试性地将南黄海灾害地质因素分为4大类。同时参考地貌沉积界线和其他因素将南黄海分成4个灾害地质区:即海岸带、苏北浅滩、海州湾和南黄海东部灾害地质区,并时各灾害地质区进行了定性评价,苏北浅滩灾害地质区是研究区内灾害地质环境最不稳定的区域。  相似文献   
45.
鱼粉脂肪酸组成的分析研究   总被引:7,自引:1,他引:7  
本文应用气相色谱对水产饲料的主要原料——— 4类进口鱼粉的脂肪酸组成进行分析 ,结果表明 :①鱼粉中主要脂肪酸含量SFA为C1 6∶0、C1 8∶0 ,MUFA为C1 8∶1、C1 6∶1 ,PUFA为EPA和DHA .② 4类鱼粉中 ,美国、新西兰、俄罗斯的鱼粉MUFA含量较为接近 ,都在 4 0 %左右 ,但新西兰鱼粉的C1 8∶1含量较美国鱼粉高 ,其平均值分别为 2 50 %和 1 9.53% ,而C 2 0∶1、C2 2∶1 ,则比美国低一些 ,俄罗斯鱼粉的含量居两者之间 .智利鱼粉的MUFA比前 3种鱼粉低 ,只有 30 %左右 .③ 4类鱼粉中新西兰鱼粉的PUFA最低 ,它们的EPA与DHA的比值为 :美国鱼粉接近 1∶1 ,新西兰鱼粉为1∶1 .5~ 1∶3.2 ,俄罗斯鱼粉为 1∶1 .2~ 1∶1 .4 ,智利鱼粉为 1∶2左右 ,④智利鱼粉的C2 2∶5n 3明显高于其它 3类鱼粉 ,而C2 0∶1、和C2 2∶1则明显低于其它 3类鱼粉  相似文献   
46.
The measurements of the vertical transport of CO2 were carried out over the Sea of Japan using the specially designed pier of Kyoto University on September 20 to 22, 2000. CO2 fluxes were measured by the eddy correlation and aerodynamic techniques. Both techniques showed comparable CO2 fluxes during sea breeze conditions: −0.001 to −0.08 mg m−2s−1 with the mean of −0.05 mg m−2s−1. This means that the measuring site satisfies the fetch requirement for meteorological observations under sea breeze conditions. Moreover, the eddy diffusivity coefficient used in the aerodynamic technique is found to be consistent with the coefficient used in the eddy correlation technique. The present result leads us to conclude that the aerodynamic technique may be applicable to underway CO2 flux measurements over the ocean and may be used in place of the bulk technique. The important point is the need to maintain a measuring accuracy of CO2 concentration difference of the order of 0.1 ppmv on the research vessels or the buoys.  相似文献   
47.
To evaluate the contribution of biogeochemical processes to the oceanic carbon cycle and to calculate the ratio of calcium carbonate to organic carbon downward export, we have incorporated biological and alkalinity pumps in the yoked high-latitude exchange/interior diffusion-advection (YOLDA) model. The biogeochemical processes are represented by four parameters. The values of the parameters are tuned so that the model can reproduce the observed phosphate and alkalinity distributions in each oceanic region. The sensitivity of the model to the biogeochemical parameters shows that biological production rates in the euphotic zone and decomposition depths of particulate matters significantly influence horizontal and vertical distributions of biogeochemical substances. The modeled vertical fluxes of particulate organic phosphorus and calcium carbonate are converted to vertical carbon fluxes by the biological pump and the alkalinity pump, respectively. The downward carbon flux from the surface layer to the deep layer in the entire region is estimated to be 3.36 PgC/yr, which consists of 2.93 PgC/yr from the biological pump and 0.43 PgC/yr from the alkalinity pump, which is consistent with previous studies. The modeled rain ratio is higher with depth and higher in the Pacific and Indian Oceans than in the Atlantic Ocean. The global rain ratio at the surface layer is calculated to be 0.14 to 0.15. This value lies between the lower and higher ends of the previous estimates, which range widely from 0.05 to 0.25. This study indicates that the rain ratio is unlikely to be higher than 0.15, at least in the surface waters.  相似文献   
48.
Based on our long-term data from megabenthos sampling from 1993 to 2002 in Ise Bay, central Japan, we examined spatio-temporal variations in taxon composition, species richness and its distribution of megabenthos in the bay in relation to the occurrence of the oxygen-poor water (i.e. oxygen content less than 3 ppm) in bottom waters of the bay. A total of 261 species were identified including 6 cnidarians, 1 tentaculate, 5 annelids, 71 molluscs, 72 crustaceans, 16 echinoderms, 12 urochordates and 78 pisces. Of the most abundant 10 megabenthos species, the following 4 species of echinoderms made up more than the half of megabenthos biomass: Luidia quinaria, Echinocardium cordatum, Asterias amurensis and Astropecten scoparius. Species richness of megabenthos varied significantly between seasons and among stations. The severity and period of occurrence of the oxygen-poor water developing every summer play an important role in determining spatial distributions of species richness in the bay.  相似文献   
49.
于2001—2004年对人工诱导大黄鱼的不同发育阶段和不同组织进行倍性检测,胚胎眼泡期采用染色体计数法测定,鱼苗和成鱼阶段用流式细胞法,结果表明,胚胎染色体数目2n=48条为二倍体,3n=72条为三倍体.采用流式细胞法测定鱼苗和成鱼个体时,若受测样品的DNA相对含量值与已知对照组二倍体的比值约为1.5:1,其个体为三倍体;比值约为1:1,则为二倍体,无论用肌肉或尾鳍组织,皆可检测出其个体的倍性。  相似文献   
50.
1 Introduction Interfacial waves travelling along the interface between two fluids of different densities can be often observed in subsurface layers of the ocean since the upper subsurface layer is warmer over much of the o- cean (Umeyama, 2002). They are…  相似文献   
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