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排序方式: 共有94条查询结果,搜索用时 31 毫秒
1.
The complete nucleotide sequence was determined for genomic RNA of White clover mosaic virus (WClMV-RC) isolated from red clover (Trifolium pratense) in Japan, It is 5843 nucleotides in length, excluding the poly(A) tail at the 3' terminus. Similar to other potexviruses, it contains five open reading frames (ORFs 1 through 5), which putatively encode an RNA-dependent RNA polymerase (RdRp) (147 kDa), a triple gene block (TGB) (26 kDa/13 kDa/7 kDa), and a coat protein (CP) (22 kDa), respectively. The deduced amino acid sequence of the WClMV-RC CP was identical to that of WClMV-O, one of two New Zealand isolates, but only 85% identical to that of WClMV-M, the other New Zealand isolate, because of heterogeneity in the C-termini of CP amino acid sequences. The implication of this CP heterogeneity is discussed. Received 30 August 2001/ Accepted in revised form 11 January 2002  相似文献   
2.
本文设计了基于RFID技术的一种刷卡式的充电服务终端硬件装置,实现刷卡自动计费。本程序以AT89S52单片机为主控制器,用MFRC500射频识别芯片进行识别,并与射频卡进行通信。  相似文献   
3.
The inelastic dynamic response analysis program for frame-shear wall structures developed by the authors is introduced firstly, in which the multi-vertical-line-element model was adopted for shear walls and the refined single-component model was used for beams and columns in frame.By analyzing three-story structural models tested in shaking-table in a famous foreign research institute, the validity of the modeling of shear wall in the program was verified. The analytical results indicate that the inelastic dynamic responseof shear walls under random ground motion input can be predicted effectively withthe program. Finally, with the preliminary discussion of some key points in modeling of shear wall, some suggestions areput forward for further improving and refining the multi-vertical-line-element model.  相似文献   
4.
Adopting the element SOLID65 and LINK8 in the general finite element analysis software ANSYS and fiber model beam-column element based on finite element flexibility method respectively, the comparative analysis of the cross, L and T-shaped RC columns under compression, bending, shear and torsion with flange width-thickness ratio of 4:1 is carried out. The applicability of plane section assumption in the nonlinear analysis is discussed primarily, which shows that it is feasible on the whole for shaped RC columns with flange width-thickness ratio equal to or smaller than 4:1.  相似文献   
5.
Based on the analysis of the status of building construction in China, the development of Assembled Structure System (ASS) can solve not only the problems in construction, but also is the key for realization of building industrialization. On the basis of technique innovations, a study on the structural performance, construction method and precast production of ASS should be carried out to inherit the old one and overcome its demerits. The process reengineering should be done in the construction enterprise to promote the development of building industrialization.  相似文献   
6.
四川省江油市500kV输变电工程工程建设造成的水土流失巨大,以江油500kV输变电工程为例,分析了该类型工程的各工程区引起的水土流失的机理,并对各工程区的水土流失量进行定量分析。结果表明:江油500 kV输变电工程的施工期为水土流失防治重点时段,水土流失主要发生在站内区,其次是进站道路区、塔基区、牵张场区和塔基施工临时占地区,工程建设中各区均将产生巨大的水土流失。根据各分区施工期水土流失预测结果,提出了相应的防治措施。  相似文献   
7.
介绍了CTE500数控电火花成型机的结构、技术参数以及机床主机安装和加工工艺参数的选择,对该机床常见故障原因进行分析并提出了解决方法,阐述了机床的操作要求和养护措施.  相似文献   
8.
对双向晶闸管的触发电路和过电压RC缓冲电路进行了研究和设计。经理论分析,本设计可以满足10kV电力用户有载调压的需求,具有广阔的发展前景。  相似文献   
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10.
In order to reduce the production cost of HRB500E seismic grade rebars, promote its production and application, HRB500E seismic grade rebars are developed by using VN microalloyed and controlled cooling process in domestic steel plant. The mechanism and effect of precipitation strengthening and fine-grain strengthening, the relationship between termination temperature after controlled cooling and mechanical properties of rebars, microstructure, welding and aging properties, high-strain and low-cycle fatigue properties for rebars are researched by using metallographic microscopy, scaning electron microcopy, transmission electron microscopy, X-ray diffraction apparatus, flash-butt welding, materials testing machine and mechanical properties testing. The results show that V(C,N) precipitation amount accounts for 66.67% of the total amount of vanadium by adding VN alloy in liquid steel, effect of microalloy precipitation strengthening is remarkable; when termination temperature after controlled cooling is controlled at 680~710 ℃, the amount of strength surplus for rebars is more than 25 MPa, R m/ R eL ratio is greater than 1.26, uniform elongation ( A gt) is more than or equal to 11.5%, good effect of fine grain strengthening and seismic performance are obtained; rebars have some good features such as low strain aging, good welding performance, high-strain and low-cycle fatigue properties; compared with VN microalloyed and hot-rolled process,the production cost is reduced by RMB 82 Yuan/t, and economic benefit is obvious.  相似文献   
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