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21.
0#柴油水溶性成分对僧帽牡蛎DNA损伤的初步研究   总被引:7,自引:0,他引:7  
郁昂  陈荣  王重刚  郑微云 《海洋科学》2004,28(11):10-14
在实验条件下,将僧帽牡蛎(Ostrea cucullata)分别置于含有低(0.5mg/L)、中(2mg/L)和高(5mg/L)3种浓度0^#柴油水溶性成分的海水中,利用碱解旋法测定消化腺和鳃INA损伤的程度。结果表明,INA损伤的程度随污染时间的延长而增加,并存在一定的剂量-效应关系;解除污染后,DNA损伤恢复到对照水平。DNA损伤可作为监测海洋石油污染的生物标志物。  相似文献   
22.
海洋石油降解微生物的分离鉴定   总被引:11,自引:0,他引:11  
刘陈立  邵宗泽 《海洋学报》2005,27(4):114-120
以柴油为惟一碳源,从胜利油田黄河码头和厦门储油码头两个海水样品中富集得到两组柴油降解菌,共9株细菌,1株真菌,它们对柴油都有降解能力.16SrDNA鉴定结果表明这9株细菌中有3株摩加夫芽孢杆菌、1株施氏假单胞菌、1株腊样芽孢杆菌、1株反硝化产碱杆菌.1株阿氏葡萄球菌、1株食烷菌和1株类似很小海旋菌的未知新菌(M-5),其中B-5对柴油的降解能力最强,已报道的食烷菌属中其他种的同源性最高,为95.2%,表明它是该属中的一个新种.实验中获得的惟一一株真菌M-3属于假丝酵母,对柴油有较强的降解和乳化能力.实验中还从B5和施氏假单胞菌M-2中扩增到了烷烃降解的限速酶烷烃单加氧酶的基因片断,其中B5编码了一种新的烷烃单加氧酶.这些菌在石油污染的海水自净中起着重要作用,可用于海洋石油污染的生物修复.  相似文献   
23.
在全球气候变暖的影响下,中国沿海的海平面上升趋势还将进一步加剧带来海水倒灌、沿海地区水质恶化、生态环境和资源破坏、侵蚀海岸、海洋自然灾害发生的频率增高等一系列危害。为缓解这些危害,首先要掌握海平面的上升速率。潮位观测数据是对海平面进行科学研究的重要依据之一,潮位数据的及时性、准确性、完整性在海平面研究中起主导作用。近年来北方冬季海面结冰现象严重,如不采取相应措施会导致验潮井内结冰,潮位数据中断,从而无法计算平均海平面高度。为防止北方冬季验潮井内结冰,常向验潮井内注入防冻柴油,但注入柴油后,验潮井内液面与外海高度不同,造成潮位观测不准确。根据潮位观测理论和多年实践经验,计算出在不影响潮位读数的情况下,可注入防冻油层的最大高度,并对超过最大高度时潮位读数的修正数值进行了研究。  相似文献   
24.
Diesel engines provide the major power sources for marine transportation and contribute to the prosperity of the worldwide economy. However, the emissions from diesel engines also seriously threaten the environment and are considered one of the major sources of air pollution. The pollutants emitted from marine vessels are confirmed to cause the ecological environmental problems such as the ozone layer destruction, enhancement of the greenhouse effect, and acid rain, etc. Marine diesel engine emissions such as particulate matter and black smoke carry carcinogen components that significantly impact the health of human beings. Investigations on reducing pollutants, in particular particulate matter and nitrogen oxides are critical to human health, welfare and continued prosperity. The addition of an oxygenating agent into fuel oil is one of the possible approaches for reducing this problem because of the obvious fuel oil constituent influences on engine emission characteristics. Ethylene glycol monoacetate was found to be a promising candidate primarily due to its low poison and oxygen-rich composition properties. In this experimental study ethylene glycol monoacetate was mixed with diesel fuel in various proportions to prepare oxygenated diesel fuel. A four-cylinder diesel engine was used to test the engine performance and emission characteristics. The influences of ethylene glycol monoacetate ration to diesel oil, inlet air temperature and humidity parameters on the engine’s speed and torque were considered. The experimental results show that an increase in the inlet air temperature caused an increase in brake specific fuel consumption (BSFC), carbon monoxide, carbon dioxide emission, and exhaust gas temperature, while decreasing the excess air, oxygen and nitrogen oxide emission concentrations. Increasing the inlet air humidity increased the carbon monoxide concentration while the decreased excess air, oxygen and nitrogen oxide emission concentrations. In addition, increasing ethylene glycol monoacetate ratio in the diesel fuel caused an increase in the BSFC while the excess air and oxygen emission concentrations decreased.  相似文献   
25.
Diesel engines are used widely as the power sources of coastal ships and international vessels primarily due to their high thermal efficiency, high fuel economy and durable performance. However, the gaseous and solid substances exhausted from diesel engines during the combustion process cause air pollution, in particular around harbor regions. In order to effectively reduce particulate matter and gaseous pollution emissions, a catalyzed particulate filter was equipped in the tail pipe of a marine diesel engine. The engine's performance and emission characteristics under various engine speeds and torques were measured using a computerized engine data control and acquisition system accompanied with an engine dynamometer. The effectiveness of installing a catalyzed particulate filter on the reduction of pollutant emissions was examined. The experimental results show that the exhaust gas temperature, carbon monoxide and smoke opacity were reduced significantly upon installation of the particulate filter. In particular, larger conversion of carbon monoxide to carbon dioxide — and thus larger CO2 and lower CO emissions — were observed for the marine diesel engine equipped with a catalyzed particulate filter and operated at higher engine speeds. This is presumably due to enhancement of the catalytic oxidation reaction that results from an exhaust gas with stronger stirring motion passing through the filter. The absorption of partial heating energy from the exhaust gas by the physical structure of the particulate filter resulted in a reduction in the exhaust gas temperature. The particulate matter could be burnt to a greater extent due to the effect of the catalyst coated on the surface of the particulate filter. Moreover, the fuel consumption rate was increased slightly while the excess oxygen emission was somewhat decreased with the particulate filter.  相似文献   
26.
海洋污染对毛蚶超氧化物歧化酶影响的研究   总被引:17,自引:0,他引:17       下载免费PDF全文
采用体内、体外染毒实验,研究了海洋中常见污染物0#柴油、二甲苯以及重金属镉离子(Cd2+)对毛蚶(Scapharca subcrenata)肌肉超氧化物歧化酶(SOD)活性的影响.结果表明,在实验剂量范围内,3种污染物对毛蚶肌肉中SOD均表现出不同程度诱导作用;0#柴油和二甲苯体内、体外染毒对毛蚶SOD活性影响规律基本一致,这两种污染物对毛蚶SOD活性变化的剂量-效应曲线均为抛物线型;Cd2+在体内、体外染毒对毛蚶肌肉SOD活性诱导曲线均不呈抛物线型,低浓度Cd2+对毛蚶SOD活性表现为显著诱导,随后曲线迅速下降,表明毛蚶对Cd2+污染反应十分敏感,也表明Cd2+对毛蚶毒性作用较强,3种毒物对毛蚶的毒性强弱次序为,Cd2+,0#柴油、二甲苯.  相似文献   
27.
EffectsofdieseloilonthepolychaeteAnnelidainmodelbenthicecosystem¥TangSenming;ChenXiaolin;ZhuangDongfa;WuShengsan;LinYu;CaiZip...  相似文献   
28.
曹金龙 《探矿工程》2012,39(8):42-45
介绍了便携式全液压钻机的结构及特点,并针对其柴油机组由于共振出现的电磁阀烧坏、保险脱落、电气线路脱落等问题进行了分析和探讨,提出了对便携式全液压钻机柴油机组出现的电器问题的解决方案。  相似文献   
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