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1.
1.凤仙碧桃 着花密;花蕾卵圆形,花梗长约0.5厘米;萼片2轮10枚,绿色,三角状卵形;花白色,形似梅花.花径4~6厘米;花瓣平展,15~30枚,广卵形,子房发育.花期4月上旬.  相似文献   
2.
For this paper, the plasma membrane (PM) H -ATPase gene has been cloned from Populus euphratica Oliv. through a homology based strategy. The isolated 3,210 bp cDNA contains a single 2,862 bp open reading frame (ORF) which encodes a putative H -ATPase protein of 953 amino acid residues, with a significant homology to plasma membrane H -ATPase of Primus persica, Phaseolus vulgaris, Sesbania rostrata and Daucus carota. The predicted protein has a molecular weight of 104,553 Da. The copy number analysis revealed multiple copies of the PM H -ATPase in the P. euphratica genome after digestion of their genomic DNA by the restriction enzymes EcoRI, NdeⅠ, FbaⅠand BglⅡ, and Southern blot.  相似文献   
3.
莲藕是我国目前出口创汇的重要蔬菜品种之一.如何使鲜藕保持新鲜、脆嫩,防止加工产品的营养价值降低,是提高藕产品质量的关键.  相似文献   
4.
郑平 《警犬》2004,(2):40-42
罗威纳犬在我国俗称“大头”犬,具有体型高大、肌肉发达、运动耐力持久、警觉性高、性情凶猛、攻击性强等特点。在治安防范、巡逻警戒、抓捕罪犯、搜毒、搜爆等使用领域越来越发挥出它的独特功能。罗威纳犬能否成为具有良好警用品质的工作犬,关键在于2~6月龄时的培养和训练。对不同月龄段罗威纳幼犬的培养及训练方法和手段是不尽相同的。  相似文献   
5.
Surgical outcome and complications following evisceration and implantation of intraocular silicone prosthesis (ISP) in 20 canine eyes with end-stage glaucoma were analyzed, including clinical signs, complications, cosmetic appearance, and owners' responses. The mean postoperative follow-up time was 312 days. Major short-term surgical complications were central corneal ulceration (6/20) and infections (3/20), while long-term complication was keratoconjunctivitis sicca (KCS) (2/20). All patient owners (100%) showed satisfied with the surgical outcome and postoperative cosmetic effect including 85% of the owners gave an excellent or good rating of satisfaction. No more medication needed for long term control except the KCS cases. With careful case selection and post-operative care, evisceration with ISP implantation proves a good and safe surgical procedure with minimal complications for end stage glaucoma.  相似文献   
6.
Magnetorheological materials are a class of smart materials whose reological properties may be rapidly varied by application of magnetic field. By a simple mechanical mold, a visco-plastic model for the materials is developed. It is shown that the model can describe the variation of the mechanical properties for the Magnetorheological materials in the different magnetic field. The result is shown that the model can characterize the mechanical properties of Magnetorheological Materials in plastic and viscous variation.  相似文献   
7.
To construct data warehouse with heterogeneous, self-governing and distributed database system is a challenge. Two problems have to be solved: one is how to collect data from heterogeneous data sources by an effective method, the other is how to clear up and change the format of the data collected from data sources. The opening and the interact-operation property of Web Services is Analyzed. A Data Collection System based on Web Services, which communicates with heterogeneous data sources with SOAP and HTTP, has been designed. A Data Collector is introduced to clear up and to transform data with composition technology. The pivotal XML technology of transforming and loading up the data are discussed.  相似文献   
8.
In this paper,a new algorithm for solving large-scale finite element system is presented, which utilizes the architecture of parallel processing. Firstly, the structure is partitioned into sub-regions. Then multi-fronts are used to assemble and eliminate concurrently in every sub-region. Thus the condensed interface stiffness matrices and load vectors are obtained. By serially assembling and solving global equation to get interface displacements and backing to every sub-region, the inter-nodal displacements and element stresses can be solved. The results of computation show that it can not only increase the speed of computation,but also save the memory space of computer effectively. This algorithm is an effective method for solving large-scale structural finite element systems.  相似文献   
9.
The high-precision displacement measuring technology of optic-measuring mechanics is, for the first time,successfully applied on the similar model of the model land-layer with a new-type variable modulus of elasticity. The angle of movement and the distributed displacement of upper and lower rock-layers are measured. The technology is a combination of laser's technology and the modern chemical sticker-it is called the sticking moire interferometry. Compared with the measured values, the result is very satisfactory.  相似文献   
10.
The design of multi-controller and multi-mode control law is presented for the three-link Acrobot on horizontal bar by employing Human simulated intelligent control method based on sensory-motor Schema.Imitated the characteristics of gymnast's swing-up and handstand movement,the control process of robot is divided by six sequence phase.Then the sensory cell and motor cell and the group of sensory-motor schema is designed based on the analysis of quality-quantity combination.The simulation results show that the controller ensures the gesture and the energy to the desired goal,farther more the motion control of giant swing backword is realized in the simulation.  相似文献   
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