某建筑工程黄土地基处理方案比较分析     

张永乾 《中国煤炭地质》2010,(2):43-45

西安某建筑工程结构复杂,平面不规整,荷载要求差异大,为自重Ⅲ级湿陷性黄土地基。根据岩土工程资料和上部荷载要求,分析本地常用的地基处理方案,并进行经济性、安全性和可行性比较,提出要根据不同的地基土参数和上部荷载要求,安全、经济、灵活地选择地基处理方案。考虑到统一工艺和施工的方便性,最终采用灰土挤密桩复合地基和桩基础方案。同时,对工程实施过程中具体的参数选择、注意事项也进行了阐述,为同类地基处理提供了参考。  相似文献   

16S rRNA gene phylogenesis of culturable predominant bacteria from diseased Apostichopus japonicus (Holothuroidea, Echinodermata)     

Haiyan Ma  Guoliang Jiang  Zhiqiang Wu  Xin Wang 《中国海洋大学学报(英文版)》2009,8(2):166-170

Cultured Apostichopus japonicus in China suffers from a kind of skin ulceration disease that has caused severe economic loss in recent years. The disease, pathogens of which are supposed to be bacteria by most researchers, is highly infectious and can often cause all individuals in the same culture pool to die in a very short time. The 16S rRNA gene phylogenesis of the culturable bacteria from the lesions of diseased individuals was conducted to study the biodiversity of the bacterial communities in the lesions and to identify probable pathogen(s) associated with this kind of disease. S. japonica samples were selected from a hatchery located in the eastern part of Qingdao, China. Bacterial universal primers GM5F and DS907R were used to amplify the 16S rRNA gene of bacteria colonies, and touchdown PCR was performed to amplify the target sequences. The results suggest that γ- proteobacteria (Alteromonadales and Vibrionales) of CFB group, many strains of which have been also determined as pathogens in other marine species, are the predominant bacterial genera of the diseased Apostichopus japonicus individuals.  相似文献   

Surface displacements due to batter piles driven in cross‐anisotropic media     

Cheng‐Der Wang  Ming‐Tang Chen  Tzen‐Chin Lee 《国际地质力学数值与分析法杂志》2008,32(2):121-141

This article derives the closed‐form solutions for estimating the vertical surface displacements of cross‐anisotropic media due to various loading types of batter piles. The loading types include an embedded point load for an end‐bearing pile, uniform skin friction, and linear variation of skin friction for a friction pile. The planes of cross‐anisotropy are assumed to be parallel to the horizontal ground surface. The proposed solutions are never mentioned in literature and can be developed from Wang and Liao's solutions for a horizontal and vertical point load embedded in the cross‐anisotropic half‐space. The present solutions are identical with Wang's solutions when batter angle equals to 0^°. In addition, the solutions indicate that the surface displacements in cross‐anisotropic media are influenced by the type and degree of material anisotropy, angle of inclination, and loading types. An illustrative example is given at the end of this article to investigate the effect of the type and degree of soil anisotropy (E/E′, G′/E′, and ν/ν′), pile inclination (α), and different loading types (a point load, a uniform skin friction, and a linear variation of skin friction) on vertical surface displacements. Results show that the displacements accounted for pile batter are quite different from those estimated from plumb piles, both driven in cross‐anisotropic media. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

16S rRNA Gene Phylogenesis of Culturable Predominant Bacteria from Diseased Apostichopus japonicus(Holothuroidea,Echinodermata)     

MA Haiyan  JIANG Guoliang  WU Zhiqiang  WANG Xin 《中国海洋大学学报(英文版)》2009,8(2)

Cultured Apostichopusjaponicus in China suffers from a kind of skin ulceration disease that has caused severe economic loss in recent years. The disease, pathogens of which are supposed to be bacteria by most researchers, is highly infectious and can often cause all individuals in the same culture pool to die in a very short time. The 16S rRNA gene phylogenesis of the culturable bacteria from the lesions of diseased individuals was conducted to study the biodiversity of the bacterial communities in the lesions and to identify probable pathogen(s) associated with this kind of disease. S. japonica samples were selected from a hatchery located in the eastern part of Qingdao, China. Bacterial universal primers GM5F and DS907R were used to amplify the 16S rRNA gene of bacteria colonies, and touchdown PCR was performed to amplify the target sequences. The results suggest that γ- proteobacteria (Alteromonadales and Vibrionales) of CFB group, many strains of which have been also determined as pathogens in other marine species, are the predominant bacterial genera of the diseased Apostichopusjaponicus individuals.  相似文献   

薄壁金刚石钻头感应加热机理探讨   总被引：2，自引：0，他引：2       下载免费PDF全文

丁华东  冯庆芬  金志浩 《探矿工程》1995,(5):34-35,56

分析了中频感应加热生产薄壁金刚石钻头的加热过程，依此提出了薄壁钻头的加热机理，为重新确定模具与感应圈的相对位置，模具设计以及设备选型提供了依据。  相似文献   

苏鲁变质带北部的岩石构造单元及结晶块体推覆构造   总被引：20，自引：0，他引：20       下载免费PDF全文

翟明国  郭敬辉  王清晨  叶凯  从柏林  刘文军 《地质科学》2000,35(1):16-26

虽然苏鲁变质带北部的超高压变质岩石的类型及其特征与大别山超高压带相似,但是要划出与大别山相对应的岩石构造单元是困难的。详细的区域地质、岩石学、同位素年代学及地球化学的研究已将超高压带的西界大致圈定在牟平断裂至米山断裂的范围内。特别需要提出的是,在荣成超高压变质岩石分布区的南北两侧,出露有3 种不同成因的麻粒岩,即榴辉岩化的麻粒岩;由超高压变质岩经高压升温变质作用生成的麻粒岩;以及未经过榴辉岩相变质的麻粒岩。它们有规律地成带分布。这些麻粒岩带以及在荣成地区出露的未经过麻粒岩相叠加变质的超高压变质带,各自都有着完全不同的变质历史,并且都以深大韧性剪切带为其边界。由此笔者将苏鲁变质带北部由南向北划分为海阳所变质地块(榴辉岩化扬子陆块基底变质单元)、荣成变质地块(超高压变质单元)、威海变质地块(麻粒岩相叠加变质的超高压构造岩片)、昆嵛山边界杂岩带。这些来源于地壳深层的结晶块体是超高压带形成和演化的产物,在后来的进一步碰撞挤压中,这些来源于深层而就位于中上地壳水平的结晶块体,有可能发生了与薄皮构造机制(thin-skin thrust)类似的构造过程。它们有如一系列的推覆体挤压叠置,使华北和华南陆块最后挤压在一起。  相似文献   

温度对鳜皮肤黏膜抗体产生的影响     

罗霞  潘厚军  巩华  石存斌  吴淑勤 《广东海洋大学学报》2007,27(3):45-49

应用间接酶联免疫吸附试验(ELISA)技术测定不同水温下鳜经嗜水气单胞菌GYK1株全菌灭活疫苗浸泡免疫后皮肤黏液中抗体,以研究抗体动态变化,揭示温度对抗体产生的影响。结果表明:27.0~29.8℃水温(下称"较高温")下,鳜皮肤黏膜抗体滴度于第7天达到峰值211,而水温介于19.8~23.9℃(下称"较低温")时,抗体滴度于第11天达到峰值26,说明温度较高时,抗体形成快,峰值出现时间早,并且抗体滴度明显升高。另取不同温度下经上述疫苗浸泡免疫的鳜皮肤黏液,采用硫酸铵盐析、离心、浓缩等生物化学技术粗提鳜皮肤黏液中的免疫球蛋白,SDS-PAGE检测发现,较高水温下,高渗免疫组(加10 mg/mL食盐)鳜皮肤黏液蛋白中目标条带(72×103和29×103)深度较其他3个实验组(同温度下全菌组、较低水温下高渗及全菌组)有所增加,ELISA检测该组抗体效价为211。  相似文献   

转录组数据的大菱鲆(Scophthalmus maximus) SNP标记开发及多态性分析   总被引：1，自引：0，他引：1  

王婷  黄智慧  马爱军  马得友  王新安  夏丹丹  马本贺 《海洋与湖沼》2014,45(6):1300-1307

大菱鲆(Scophthalmus maximus)是最具商业价值和养殖前途的海水鱼类之一, 雌雄间生长有一定的差异。其高通量雌雄转录组测序的完成为大规模鉴定和开发SNP标记提供了参考序列。本研究基于大菱鲆雌雄转录组测序数据, 选择其中45个SNP位点, 设计引物63组, 其中21个位点(46.7%)应用小片段高分辨率熔解曲线(HRM)技术分型成功。对其进行多态性检测, 21个位点均具有二个单倍型。观测杂合度Ho的分布范围为0.256—1.000, 期望杂合度He的范围为0.276—0.518, 19个位点符合Hardy-Weinberg平衡。14个SNP位点位于基因编码区, 其中3个属于非同义突变。含有这些SNP位点的基因大多与信号转导和转录翻译相关。本研究结果表明, 高通量转录组测序和小片段HRM适合大规模SNP标记开发, 为大菱鲆的分子遗传育种提供了候选标记资源。  相似文献   

The eco-nutrition requirements for dietary protein and its rhomb characteristics in juvenile turbot (Scophthalmus maximus L.)     

����  ������  �����  ������  �ܰ�ά 《中国海洋湖沼学报》2011,29(5):1002-1008

We evaluated the dietary protein requirements of juvenile turbot (Scophthalmus maximus L.) and their effects on aquatic quality. Five experimental diets were formulated containing 450, 480, 500, 520, and 540 g/kg. Each diet was randomly assigned to triplicate groups of juvenile turbot (mean initial body weight 34.5 ± 5.5 g) for 88 d. Both the weight gain ratio and feed efficiency increased with increasing dietary protein up to 500 g/kg, but no further improvement was detected when dietary protein levels were >500 g/kg. Protein intake and digestion increased with protein levels, while fecal nitrogen and nitrogen content in seawater increased only when dietary protein exceeded 500 g/kg. Protein digestibility was highest at intermediate dietary protein levels. Chemical oxygen demand, nitrite-nitrogen (NO2--N) and phosphatic-phosphor (PO43--P) levels increased in the rearing water as dietary protein levels increased. The optimum eco-nutrition level of dietary protein for juvenile turbot was 500 g/kg under the current experimental conditions. The diets containing 540 and 500 g/kg protein had similar growth rates and feed conversion ratios, but levels of ammonia (NH4+) and nitrogen were considerably higher in the water and feces, respectively, at the higher level of dietary protein. The difference in the pattern of change between body weight gain and ammonia concentration in water with increasing dietary protein is described by rhomb characteristics.  相似文献   

Turbot Scophthalmus maximus：stocking density on growth, pigmentation and feed conversion   总被引：1，自引：1，他引：0  

马爱军 陈超雷霁霖  陈四清庄志猛 王印庚 《中国海洋湖沼学报》2006,24(3):307-312

1 INTRODUCTION Turbot is a type of marine flatfish naturally distributing along the coastal area of European. It is highly demanded for good taste. The price therefore, is very expensive. To meet the consump- tion, large-scale turbot cultures were perform…  相似文献