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41.
Abstract The whole DNA of soybean was implanted into four varieties of wheat of Zhongyu5, Huaiyin 9628, Wenyou 1, Jimai 5 respectively via ion-beam mediation. There were 5 plantsobtained whose protein content was higher than 18.5%, the highest one was 21.44%. There were 3plants obtained whose protein content was lower than 11.5%, the lowest one was 10.96%. We cansee that the whole DNA of soybean transformed into wheat via ion beam implantation can inducethe increase in wheat protein content dramatically. The result also shows that the transformationefficiency of different gene types of wheat receptor varies greatly that the implanting time has acertain effect on the efficiency of transformation.  相似文献   
42.
Polycrystalline A1N thin films were deposited by RF reactive magnetron sputtering on Pt(111)/Ti electrode films. The substrates were tilted by an angle ranging from 40 degrees to 70 degrees with respect to the target normal. A low deposition temperature and a high sputter gas pressure were found ideal for tilted growth. The resulting grain tilt angle amounts to about half the substrate tilt angle. For coupling evaluation, 5 GHz solidly mounted resonator structures have been realized. The tilted grain A1N films exhibited a permittivity in the 9.5-10.5 range and loss tangent of 0.3%. Two shear modes as well as the longitudinal mode could be clearly identified. The coupling coefficient k2(eff) of the fundamental thickness shear mode (TS0) was found to be about 0.5%, which is compatible with a c-axis tilt of about 6 degrees.  相似文献   
43.
低噪声GaAs FET和功率GaAs FET经中子辐射都未发生致命性的通或断失效,直流偏置伏态下,其失效模式仅仅表现为源漏饱和电流IDSS的退化降低,据此提出了IDSS退化失效与快中子注量φn之间的解析关键式lny=a+blnφ。  相似文献   
44.
Skyline and top-k queries are two popular operations for preference retrieval. In practice, applications that require these operations usually provide numerous candidate attributes, whereas, depending on their interests, users may issue queries regarding different subsets of the dimensions. The existing algorithms are inadequate for subspace skyline/top-k search because they have at least one of the following defects: 1) they require scanning the entire database at least once, 2) they are optimized for one subspace but incur significant overhead for other subspaces, or 3) they demand expensive maintenance cost or space consumption. In this paper, we propose a technique SUBSKY, which settles both types of queries by using purely relational technologies. The core of SUBSKY is a transformation that converts multidimensional data to one-dimensional (1D) values. These values are indexed by a simple B-tree, which allows us to answer subspace queries by accessing a fraction of the database. SUBSKY entails low maintenance overhead, which equals the cost of updating a traditional B-tree. Extensive experiments with real data confirm that our technique outperforms alternative solutions significantly in both efficiency and scalability.  相似文献   
45.
陶六珍 《小水电》2007,(4):28-29
元江县5 000t金属镍矿建设项目,是玉溪市“十一五”期间的重点工程,其项目建成投产后,将对元江县乃至玉溪市的经济发展起到重要的推动作用。省市两级党委和政府对此十分重视,积极促进和推动该项目的建设进程。该项目达到设计规模时,年生产用水将达500万m3,小板壁水库即为该项目  相似文献   
46.
本文介绍了模糊技术的发展和现状,以及在相关领域中的应用情况,并且讨论了模糊技术在我国的产业化方向等问题。  相似文献   
47.
48.
In this paper, a hybrid integrator backstepping controller is proposed for robotic manipulators actuated with brushless DC motors in the presence of arbitrary uncertain inertia parameters of the manipulator and the electrical parameters of the actuators. The main features are: 1) the design, requiring at most the joint velocities and stator currents feedback; 2) the semiglobal asymptotic stability of the controller being established in the Lyapunov sense; and 3) suitability of the scheme for multijoint robots. Simulation results are included to demonstrate the tracking performance.  相似文献   
49.
詹涛 《吉林水利》2021,(10):58-61
针对临近水库的别墅等建筑物的清查整治,在实体层面,尤其对于五证齐全的建筑物,如何定性为违建需要慎重把握,对水库管理范围的界定是一个重点问题;在程序层面,应避免执法中因急于求成而催生的程序违法.强拆行为会产生重大损失,涉及多方主体和多重法律关系,应理清其中各方的法律责任,妥善解决纠纷.  相似文献   
50.
To clarify some of the solid-state aspects of cold fusion in deuterated transition metal electrodes, we have carried out first-principles self-consistent total energy calculations for various configurations of atomic and diatomic deuterium inside fcc palladium. We find that the stability of the Pd+D system is controlled by the relative position of the deuterium-inducedantibonding level with respect to the Fermi energy. The equilibrium D-D distance in dense PdD up to =3 is found to be much larger than the free space value. The calculated Born-Oppenheimer energy surface of diatomic D2 in crystalline palladiuim is shown to have but metastable local minima whose internuclear separation is at least 0.2 Ålarger than that of the isolated D2 molecule. We conclude that D2 incrystalline Pd will have a substantially lower tunneling probability than hitherto thought and that explanation for fusion mechanisms should be sought elsewhere.  相似文献   
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