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Rice leaf inclination2, a VIN3-1ike protein, regulates leaf angle through modulating cell division of the collar 被引量:36
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作者 Shu-Qing Zhao Jiang Hu +2 位作者 Long-Biao Guo Qian Qian Hong-Wei Xue 《Cell Research》 SCIE CAS CSCD 2010年第8期935-947,共13页
As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three all... As an important agronomic trait, inclination of leaves is crucial Ior crop architecture and grain yields. 10 understand the molecular mechanism controlling rice leaf angles, one rice leaf inclination2 (1c2, three alleles) mutant was identified and functionally characterized. Compared to wild-type plants, lc2 mutants have enlarged leaf angles due to increased cell division in the adaxial epidermis of lamina joint. The LC2 gene was isolated through positional cloning, and encodes a vernalization insensitive 3-like protein. Complementary expression of LC2 reversed the enlarged leaf angles of lc2 plants, confirming its role in controlling leaf inclination. LC2 is mainly expressed in the lamina joint during leaf development, and particularly, is induced by the phytohormones abscisic acid, gibberellic acid, auxin, and brassinosteroids. LC2 is localized in the nucleus and defects of LC2 result in altered expression of cell division and hormone-responsive genes, indicating an important role of LC2 in regulating leaf inclination and mediating hormone effects. 展开更多
关键词 leaf inclination RICE VIN3-1ike protein cell division LC2
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聚氨酯-脲——水声换能器及水听器用新型透声密封材料 被引量:4
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作者 张景亮 《橡塑资源利用》 2011年第1期26-29,共4页
几乎所有水声发射器和水听器都采用聚合材料封装。这些覆盖层可使声波穿过时无明显反射、损耗或失真,还可保护水声传感器及电子设备免受物理损坏和海水侵蚀。具有优越声学性能的材料应具有以下主要参数指标:⑴密度和声速接近海水;⑵低... 几乎所有水声发射器和水听器都采用聚合材料封装。这些覆盖层可使声波穿过时无明显反射、损耗或失真,还可保护水声传感器及电子设备免受物理损坏和海水侵蚀。具有优越声学性能的材料应具有以下主要参数指标:⑴密度和声速接近海水;⑵低机械损耗角正切;⑶中到高剪切损耗角正切;⑷低剪切储能模量;⑸泊松比接近0.50;⑹在研究频率和研究温度内无显著聚合物变化。Division Newport的海军水下作战中心(NUWC)于近期合成了一种新的聚氨酯脲弹性体,用作传感器和水听器的密封材料。这种NUWC XP-1材料,利用异氰酸甲苯酯/聚醚多元醇作基料(分子量约为1500),DMTDA作交联剂或硫化剂。NUWC XP-1在室温下硫化一整夜,达到邵尔A硬度75度。在室温下,XP-1R的声速与海水的非常接近,25℃时的声阻抗为1.71×106瑞耳。NUWC XP-1的水下玻璃化转化温度为-31℃,其动态力学性能使其成为近乎理想的水下传感器/水听器密封材料。将其与几种常用的商业性聚氨酯密封材料比较后(例如中华人民共和国与德索托联合生产的PR-1547、PR-1592;Cyte公司生产的Conathane EN-7)得出结论,NUWC XP-1的性能等于或好于几乎所有能有效密封声学设备和传感器的材料。本产品给行业带来的特殊利益在于NUWC XP-1的化学配方由美国海军控制,且该材料由基本原材料制成,因此相比许多其他商业产品来说,它在未来的使用更广。 展开更多
关键词 密封材料 水声换能器 聚氨酯- 水听器 division 水声传感器 损耗角正切 聚氨酯脲弹性体
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Effect of Surface Roughness in Micro-nano Scale on Slotted Waveguide Arrays in Ku-band
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作者 Na LI Peng LI Liwei SONG 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期595-603,共9页
Modeling of the roughness in micro-nano scale and its influence have not been fully investigated, however the roughness will cause amplitude and phase errors of the radiating slot, and decrease the precision and effic... Modeling of the roughness in micro-nano scale and its influence have not been fully investigated, however the roughness will cause amplitude and phase errors of the radiating slot, and decrease the precision and efficiency of the SWA in Ku-band. Firstly, the roughness is simulated using the electromechanical coupled(EC) model. The relationship between roughness and the antenna's radiation properties is obtained. For verification, an antenna proto- type is manufactured and tested, and the simulation method is introduced. According to the prototype, a contrasting experiment dealing with the flatness of the radiating plane is conducted to test the simulation method. The advantage of the EC model is validated by comparisons of the EC model and two classical roughness models (sine wave and fractal function), which shows that the EC model gives a more accurate description model for roughness, the maxi- mum error is 13%. The existence of roughness strongly broadens the beamwidth and raises the side-lobe level of SWA, which is 1.2 times greater than the ideal antenna. In addition, effect of the EC model's evaluation indices is investigated, the most affected scale of the roughness is found, which is 1/10 of the working wavelength. The proposed research provides the instruction for antenna designing and manufacturing. 展开更多
关键词 Slotted waveguide arrays - Roughness model Micro/nano-scale amplitude and phase errors Radiationcharacteristics
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4.2 GeV α-^(12)C Elastic Scattering Based on α-Particle Mode
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作者 YANG Yong-Xu LU Xiao LI Qing-Run 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1587-1590,共4页
Based on the α-particle model of ^12C nucleus, the differential cross sections for α-^12C elastic scattering at incident energy of 4.2 GeV have been calculated within the framework of Glauber multiple scattering the... Based on the α-particle model of ^12C nucleus, the differential cross sections for α-^12C elastic scattering at incident energy of 4.2 GeV have been calculated within the framework of Glauber multiple scattering theory. The results show that the main features of the measured angular distribution of the cross sections can be reasonably described. The parameterized α-α scattering amplitude, which is the basic input to construct the α-^12 C scattering Glauber amplitude in the a-particle model, is obtained by fitting the α-α scattering data. 展开更多
关键词 α-nucleus elastic scattering nuclear a-particle model α-α scattering amplitude
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A New Efficient Finite Volume Modeling of Small Amplitude Free Surface Flows with Unstructured Grid
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作者 吕彪 《China Ocean Engineering》 SCIE EI CSCD 2013年第4期509-522,共14页
A staggered finite-volume technique for non-hydrostatic, small amplitude free surface flow governed by the incompressible Navier-Stokes equations is presented there is a proper balance between accuracy and computing t... A staggered finite-volume technique for non-hydrostatic, small amplitude free surface flow governed by the incompressible Navier-Stokes equations is presented there is a proper balance between accuracy and computing time. The advection and horizontal diffusion terms in the momentum equation are discretized by an integral interpolation method on the orthogonal unstructured staggered mesh and, while it has the attractive property of being conservative. The pressure-correction algorithm is employed for the non-hydrostatic pressure in order to achieve second-order temporal accuracy. A conservative scalar transport algorithm is also applied to discretize k - c equations in this model. The eddy viscosity is calculated from the k-c turbulent model. The resulting model is mass and momentum conservative. The model is verified by two examples to simulate unsteady small amplitude free surface flows where non-hydrostatic pressures have a considerable effect on the velocity field, and then applied to simulate the tidal flow in the Bohai Sea. 展开更多
关键词 orthogonal unstructured grid NON-HYDROSTATIC small amplitude free surface flows 3-D numerical model k - ~ turbulent model
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The Optimizing Model and Its Solution for Making Train Working Graph with Computer on Separative Division of Double-Track Lines
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作者 Peng Qiyuan Ju Tingying(Department of Transportation Engineering),Soulhudest Jiaolong Universily,Chengdu 610031,China 《Journal of Modern Transportation》 1994年第2期181-188,共8页
The authoros specialize in the field of optunization and automatic programme oftrain working graph. In this peper, at frist, a mixed 0-1 integer progranimingmodel about this problem for duuble-track lines is set up, t... The authoros specialize in the field of optunization and automatic programme oftrain working graph. In this peper, at frist, a mixed 0-1 integer progranimingmodel about this problem for duuble-track lines is set up, then the principle andProcess of selution are stated, with an application exaiiiple put forward. 展开更多
关键词 train workins graph double-tracK line division mixed 0-1 mtegerprosrammins COMPUTER
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Altered relationship between thickness and intrinsic activity amplitude in generalized tonic–clonic seizures 被引量:3
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作者 Wei Liao Jue Wang +10 位作者 Ting Xu Zhiqiang Zhang Gong-Jun Ji Qiang Xu Zhengge Wang Fang Yang Xi-Nian Zuo Anqi Qiu Yu-Feng Zang Guangming Lu Huafu Chen 《Science Bulletin》 SCIE EI CAS CSCD 2016年第24期1865-1875,共11页
A thinner cortex has higher potential for binding GABA receptor A which is associated with larger amplitudes of intrinsic brain activity(i BA). However, the relationship between cortical thickness and i BA is unknown ... A thinner cortex has higher potential for binding GABA receptor A which is associated with larger amplitudes of intrinsic brain activity(i BA). However, the relationship between cortical thickness and i BA is unknown in intact and epileptic brains. To this end, we investigated the relationship between cortical thickness measured by highresolution MRI and surface-based i BA derived from resting-state functional MRI in normal controls(n = 82) andpatients with generalized tonic–clonic seizures(GTCS)only(n = 82). We demonstrated that the spatial distribution of cortical thickness negatively correlated with surface-based i BA amplitude at both whole-brain and within independent brain functional networks. In GTCS patients,spatial coupling between thickness and i BA amplitude decreased in the default mode, dorsal attention, and somatomotor networks. In addition, the vertex-wise acrosssubject thickness–i BA amplitude correspondence altered in the frontal and temporal lobes as well as in the precuneus in GTCS patients. The relationship between these two modalities can serve as a brain-based marker for detecting epileptogenic changes. 展开更多
关键词 Cortex thickness - Generalized tonicclonic seizures - Intrinsic brain activity amplitude -Morphometric-functional relationship ~ Resting state
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Adaptive Delayed Acknowledgement Algorithm for MPEG-4 Traffic in UWB Networks
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作者 刘新 戴琼海 吴秋峰 《Tsinghua Science and Technology》 SCIE EI CAS 2006年第3期278-286,共9页
Although ultra-wideband transmission rates are very high in the physical layer, the bandwidth utilization efficiency is very low in the medium access control (MAC) layer. The bandwidth utilization efficiency can be ... Although ultra-wideband transmission rates are very high in the physical layer, the bandwidth utilization efficiency is very low in the medium access control (MAC) layer. The bandwidth utilization efficiency can be improved and the quality of service for delay-sensitive variable bit rate traffic such as high rate motion picture experts group (MPEG)-4 traffic can be guaranteed by a simple and efficient algorithm that dynamically sets the burst size of the delayed-acknowledgement (Dly-ACK) based on the I EEE 802.15.3 standard. The burst size was adjusted in response to the wireless channel quality. Furthermore, the burst size was bounded by a maximum acknowledgement burst size setting and the remaining number of un-received blocks of a current supra-block. Simulation results show that the method achieves significant performance enhancement in the job failure rate and throughput compared to immediate-acknowledgement (Imm-ACK) and other fixed burst size Dly-ACK schemes. This algorithm can also be applied in generalized time division multiple access (TDMA) systems by using the block acknowledgement mechanism for delay sensitive traffic. 展开更多
关键词 delayed-acknowledgement (Dly-ACK) ULTRA-WIDEBAND medium access control (MAC) motionpicture experts group (MPEG)-4 time division multiple access (TDMA)
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The Characteristics of Putaohua Reservoir and Development Strategies in Xujiaweizi Baxin Oilfield
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作者 GUO Qingxia(Exploration and Development Research Institute of Daqing Oilfield, Heilongjiang 163453, P. R.China)YANG Haibo( The Advanced Personnel Training Center of Daqing Oilfield, Heilongjiang 163453, P,R, China) 《Global Geology》 2002年第1期89-95,共7页
With the using of new full 3 - D interpretative technology, the carefully interpretation of the micro - amplitude structures and faults by the reprocessed 3 -D seismic data in IES (Interactive Exploration System) inte... With the using of new full 3 - D interpretative technology, the carefully interpretation of the micro - amplitude structures and faults by the reprocessed 3 -D seismic data in IES (Interactive Exploration System) interpretative system of Sun workstation is obtained. Because of the application of the well - advanced predictive technique for reservoir lithological changes, the predictive accuracy rate of drilling for 31 wells drilled in 1996 achieved 100 % and the economic and social benefits are desirable. 展开更多
关键词 Full 3 - D MICRO - amplitude structure STRATEGY
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