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11.
Grouper iridovirus (GIV) belongs to the Ranavirus genus and is one of the most important viral pathogens in grouper, particularly at the fry and fingerling stages. In this study, we identified and characterized the GIV‐2L gene, which encodes a protein of unknown function. GIV‐2L is 1242 bp in length, with a predicted protein mass of 46.2 kDa. It displayed significant identity only with members of the Ranavirus and Iridovirus genera. We produced mouse monoclonal antibodies against the GIV‐2L protein by immunizing mice with GIV‐2L‐His‐tag recombinant protein. By inhibiting de novo protein and DNA synthesis in GIV‐infected cells, we showed that GIV‐2L was a late gene during the viral replication. Finally, immunofluorescence microscopy revealed that GIV‐2L protein accumulated in both the nucleus and cytoplasm of infected cells. These results offer important insights into the pathogenesis of GIV.  相似文献   
12.
通过对优质抗病滇型杂交粳稻滇杂31不同栽插密度在云南温暖粳稻区的牟定县和温凉粳稻区的大理市进行试验,试验结果分析表明:滇杂31在温暖粳稻区的栽插密度以30.0万丛/hm2,2苗/丛产量最高,不同栽插密度之间产量差异达极显著水平;在温凉粳稻区的栽插密度以45.0万丛/hm2,2苗/丛产量最高,不同栽插密度之间产量差异达显著水平。  相似文献   
13.
日光温室环境参数的测定及分析   总被引:5,自引:0,他引:5  
对北京地区普通日光温室的气象环境参数进行测定。分析了温室的室温、地温及湿度等变化规律,并对变化规律进行了讨论研究  相似文献   
14.
15.
A04034、A04008和苯氧菌酯、嘧菌酯和肟菌酯等甲氧丙烯酸酯类杀菌剂在盆栽试验中对黄瓜白粉病均表现出优异的保护和治疗活性。其中A04034表现出尤为卓越的杀菌活性,其对黄瓜白粉病的保护作用EC50、EC90为0.98μg/mL、3.12μg/mL,治疗作用EC50、EC90为1.17μg/mL、5.22μg/mL,其保护活性和治疗活性在5种药剂中均为最佳。田间药效试验中,10?4034悬浮剂用5、10、20g.a.i/hm2的剂量第3次施药后7d的防效分别为82.7%、89.3%、91.7%;25%嘧菌酯乳油(阿米西达)10g.a.i/hm2的防效为84.0%;10?4008悬浮剂用5、10、20g.a.i/hm2第3次施药后7d的防效分别为73.2%、86.4%、86.5%。10?4034和10?4008悬浮剂用10g.a.i/hm2的防效均略高于25%嘧菌酯乳油(阿米西达)10g.a.i/hm2的防效,防效无显著差异。  相似文献   
16.
This paper reports about the modification of sand and fumed silica with titania in order to obtain a photocatalytic active material for the degradation of pollutants. The coating process was performed based on the sol–gel method. Tetrapropylorthotitanate was used as the titania precursor to apply a nanoscaled layer on sand grains. For silica fume, the coating process was varied. Various amounts of tetrapropylorthotitanate were used to obtain different coating thicknesses and to identify the maximum amount of titania that could be loaded on the material. All samples showed high photonic efficiencies in the degradation of nitrogen monoxide despite their low titania quantities, which were identified via x-ray fluorescence analysis. Some samples showed higher photonic efficiencies than commercial Degussa P25. Due to the preparation method, calcination of the sand composites was not necessary to yield a crystalline coating which was responsible for the high photocatalytic activity. However, silica fume composites had to be calcined possibly due to variation in the preparation method. Scanning electron micrographs revealed the structured morphology of all specimens. Energy dispersive x-ray analysis identified nanoscaled titania particles on the sand surface that could not be observed only via SEM. The results of this research are especially interesting for large scale applications of photocatalysts. As industrial sand and silica fume used are low cost materials, this new kind of photocatalyst can be applied in higher quantities and distributed onto larger areas, while saving costs at the same time.  相似文献   
17.
固定顶油罐大型化的技术经济问题   总被引:1,自引:0,他引:1  
刘志伟 《油气储运》1998,17(3):42-44
论述了建造大型化固定顶油罐的必要性,大型油罐良好的经济性能是推动油罐大型化的直接接动因。对金属油罐建设费用的构成进行了分析,并以实例对油罐在钢材方面,土地使用方面,各项费用指标,辅助工程费用及操作费用等方面分析了讨论,指出增大油罐容积,可降低工程项目的建设和操作费用,减少投资提高工程项目的经济效益。  相似文献   
18.
为建立一种简便、快速、重现性好的高效液相色谱-荧光检测器检测蜂蜜中的诺氟沙星、环丙沙星、单诺沙星、恩诺沙星、沙拉沙星、双氟沙星6种氟喹诺酮残留量的方法,采用QuEChERS-液相色谱法同时测定蜂蜜中6种氟喹诺酮类药物残留。结果表明:QuEChERS测定6种氟喹诺酮的分离度较好,在0.02~0.5μg/mL具有良好的线性关系(r=0.999 9),检出限为0.97~3.91μg/kg,平均加标回收率为72%~115%。相对标准偏差在1.4%~11%。  相似文献   
19.
Successful natural spawning of Pomacanthus semicirculatus in captivity from 11 September to 18 October, 2006 is described for the first time. Each female laid an average of 230 000 eggs during the spawning period. Fertilized eggs were spherical, transparent and buoyant and had a mean diameter of 0.61 ± 0.03 mm (mean ± SD). Embryonic development lasted 18–21 h at 28.5 °C. Newly hatched larvae were 1.35 ± 0.02 mm in total length (TL) with 27 (12+15) myomeres and had an oil globule in the ventroposterior area of the yolk sac. Larvae completed yolk absorption within 3 days post hatching at 2.37 ± 0.05 mm TL. Larvae were fed either 100% microalgae ( Nannochloropsis sp.), 100% s-type rotifers ( Brachionus rotundiformis ), 100% dinoflagellates ( Gonyaulax sp.) or different combinations of the three (50%:50%:0%, 30%:35%:35%) to determine the effect of live feed on the survival rate. The survival was significantly ( P <0.001) better in larvae fed a combination of diets (30%: 35%: 35%) than others. These results indicate that P. semicirculatus is a potential species for captive-breeding programmes and the use of a combination of diets (microalgae plus s-type rotifers and dinoflagellates) may be a suitable first food for fish larvae.  相似文献   
20.
根据陕北黄土高原的自然生态环境,果树生产现状和果树分区原则,将该区果树生产划分为北部神府海红果产区,毛乌素沙地酿酒、制汁葡萄产区,横山、白于山山区山杏、山桃产区,延河中下游商品苹果、梨产区,黄河沿岸优质红枣产区,中部、南部多种果树产区,洛川塬优质苹果产区7个区域,提出各区果树发展的主要方向、规模和发展措施。  相似文献   
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