A reovirus disease in cultured mud crab, Scylla serrata, in southern China

A reovirus, designated mud crab reovirus (MCRV), associated with large economic losses was recently isolated from marine cultured mud crab, Scylla serrata, in southern China. The complete viral particle is 70 nm in diameter, icosahedral and non-enveloped. The virus infects connective tissue cells of the hepatopancreas, gills and intestine in mud crab and develops in the cytoplasm. Hundred per cent mortality was observed in mud crab experimentally infected by intramuscular injection, bath inoculation and oral inoculation, while cohabitation infection caused 80% mortality. The viral genome consists of 13 linear dsRNA segments, with an electrophoretic pattern 1/5/7. The results of this study suggest that the virus is highly pathogenic and can be transmitted enterically as well as via the body surface of mud crab. Although the genomic organization of this virus is different from that of the other crab reoviruses, CcRV-W2 and DpPV, all three of these reoviruses have similar electrophoresis patterns. Therefore, MCRV may be a new member of the DpPV and CcRV-W2 group.     

Analysis of Spectral Characteristics Based on Optical Remote Sensing and SAR Image Fusion

Because of cloudy and rainy weather in south China, optical remote sens-ing images often can＇t be obtained easily. With the regional trial results in Baoying, Jiangsu province, this paper explored the fusion model and effect of ENVISAT/SAR and HJ-1A satel ite multispectral remote sensing images. Based on the ARSIS strat-egy, using the wavelet transform and the Interaction between the Band Structure Model （IBSM）, the research progressed the ENVISAT satel ite SAR and the HJ-1A satel ite CCD images wavelet decomposition, and low/high frequency coefficient re-construction, and obtained the fusion images through the inverse wavelet transform. In the light of low and high-frequency images have different characteristics in differ-ent areas, different fusion rules which can enhance the integration process of self-adaptive were taken, with comparisons with the PCA transformation, IHS transfor-mation and other traditional methods by subjective and the corresponding quantita-tive evaluation. Furthermore, the research extracted the bands and NDVI values around the fusion with GPS samples, analyzed and explained the fusion effect. The results showed that the spectral distortion of wavelet fusion, IHS transform, PCA transform images was 0.101 6, 0.326 1 and 1.277 2, respectively and entropy was 14.701 5, 11.899 3 and 13.229 3, respectively, the wavelet fusion is the highest. The method of wavelet maintained good spectral capability, and visual effects while improved the spatial resolution, the information interpretation effect was much better than other two methods.     

红木家具木材种类和性质初探

根据国家标准,属于“红木”范围的树种为豆科的5属8类33种．5属是以树木学的属来命名的,即紫檀属、黄檀属、崖豆属、柿属、铁刀木属．8类是以木材商品名来命名的,即紫檀木类、花梨木类、香枝木类、黑酸枝类、红酸枝类、乌木类、务纹乌木类、鸡翅类．介绍了33个红木树种的名称、木材结构、气干密度、等级划分等．     

云南省百草岭自然保护区植被的基本类型

依据 1999年 5～ 6月的样地调查资料和野外记录 ,按《云南植被》 (1987)的植被分类原则 ,将云南省百草岭自然保护区的植被分为 6个植被型 ,9个植被亚型和 13个群系。对其植被类型的分布规律以及各植被类型的特征作了较详尽的分析和记述     

福宝山水库景观规划设计

针对福宝山水库的现状,提出了合理开发旅游资源的规划方法及思路。在保护自然资源的同时,开发体现民族特色和地方特色的旅游产品,获取一定的经济效益,反哺环境保护,实现生态旅游资源保护与开发良性循环和可持续发展。     

CHANGE OF SURFACE CHARACTERISTICS DURINGOXYGEN BLEACHING OF SULPHATE PULP

INTRODUCTIONAtpresent,oxygenbleachinghasbecomeanlndustrializedtechnolOgy.Uptol989,thistechnologyhadbeenusedin58paPerndlls,and50%ofthemwereinEuroPe,20%inNorthemAmencaand20%inJapan.Inrecentyears,severaloxygnbleachiofequiPmenthadbeenintroducedintoChina.Inaword,oxygenbleachinglsasuccessfulandenviron-mentallyaccePtableprocessfOrPulpbleaching.However,littleworkhadbeendevotedtounderstandingthefundamentalaspectsofthissysten1,sotherewaslittledetailedinfOrmationonthel11echanismsofoxygenbleachi…     

浅析冷铺沥青材料的特性、配制及应用

储存式冷铺沥青混合料,是指平时储存在仓库内,使用对在常温下进行摊铺和压实的材料.文章着重介绍了这种冷铺沥青材料的特性、配制原理及应用技术要求.