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101.
研究了各向同性与正交异性双材料Ⅲ型非对称界面端问题。利用复合材料断裂复变方法,根据任意角度的界面连续条件,求解一类调和方程组的边值问题,讨论了非对称情况下含奇异指数的特征方程,得到了Ⅲ型非对称凸角、凹角界面端的应力场、位移场、应力强度因子的表达式,以及斜平面角界面端应力场奇异性的变化规律。 相似文献
102.
从横观各向同性材料的半无限体点力解出发,用积分的方法得到了半无限体内作用圆环载荷的解,对于材料特征根互不相等或相等的两种可能情形都给出了表达式,因此,可直接退化到各向同性材料半无限体内部作用圆环载荷的解. 相似文献
103.
通过Hankel变换求解了横观各向同性饱和地基在简谐扭矩作用下的动力方程,结合基础与地基接触面为混合边界和基岩面处地基位移为零的边界条件,建立了刚性基础的扭转对偶积分方程,化对偶积分方程为第二类Fredholm积分方程求解了相应的动力响应问题,并给出了基础的动力柔度系数和角位移幅值以及基底接触剪应力的表达式.数值分析结果表明:下卧基岩饱和地基上基础扭转动力柔度系数的实部和虚部都呈现出一定的波动,地基的各向异性程度对基础的动力柔度系数和扭转角位移幅值有很大影响;基础的振动频率和地基的各向异性程度对基底接触剪应力的分布也有一定影响. 相似文献
104.
永磁同步电机磁体装配工艺探讨 总被引:1,自引:0,他引:1
通过对磁体转子镶嵌式稀土永磁同步电动机FTY2600-6的研究,探讨相应的转子磁体装配工艺,介绍一种新型的磁体压装模具。批量生产验证了该工艺的有效性。 相似文献
105.
Lethmate R Ratiney H Wajer FT Crémillieux Y van Ormondt D Graveron-Demilly D 《Magma (New York, N.Y.)》2003,16(1):21-28
A method—PA-keyhole—for 2D/3D dynamic magnetic resonance imaging with radial scanning is proposed. PA-keyhole exploits the
inherent strong oversampling in the center of k-space, which contains crucial temporal information regarding contrast evolution. The method is based on: (1) a rearrangement
of the temporal order of 2D/3D isotropic distributions of trajectories during the scan into subdistributions according to the desired time resolution, (2) a new post-acquisition keyhole approach based on the replacement of the central disk/sphere in k-space using data solely from a subdistribution, and (3) reconstruction of 2D/3D dynamic (time-resolved) images using 2D/3D-gridding
with Pipe's approach to the sampling density compensation and 2D/3D-IFFT. The scan time is not increased with respect to a
conventional 2D/3D radial scan of the same spatial resolution; in addition, one benefits from the dynamic information. The abilities of
PA-keyhole and the sliding window techniques to restore simulated dynamic contrast changes are compared. Results are shown
both for 2D and 3D dynamic imaging using experimental data. An application to in-vivo ventilation of rat lungs using hyperpolarized
helium is demonstrated.
Electronic Publication 相似文献
106.
以哈尔滨市小城镇为研究对象,提出了建立创新体系的目标定位,构建了创新体系的系统结构,分析了各个主在经济主体的相互作用关系,探讨了实现创新体系有效运行应当建立的若干机制。哈尔滨市小城镇创新体系的建立和有效运行,将带动哈尔滨市小城镇建设向更高层次发展。 相似文献
107.
108.
Jan Knop Tim Lienemann Haifa El-Kilani Sven Falke Catharina Krings Maria Sindalovskaya Johannes Bergler Christian Betzel Stefan Hoth 《International journal of molecular sciences》2021,22(17)
Plant U-box armadillo repeat (PUB-ARM) ubiquitin (Ub) ligases have important functions in plant defense through the ubiquitination of target proteins. Defense against pathogens involves vesicle trafficking and the formation of extracellular vesicles. The PUB-ARM protein SENESCENCE ASSOCIATED UBIQUITIN E3 LIGASE1 (SAUL1) can form patches at the plasma membrane related to tethering multi-vesicular bodies (MVBs) to the plasma membrane. We uncovered the structure of a full-length plant ubiquitin ligase and the structural requirements of SAUL1, which are crucial for its function in patch formation. We resolved the structure of SAUL1 monomers by small-angle X-ray scattering (SAXS). The SAUL1 model showed that SAUL1 consists of two domains: a domain containing the N-terminal U-box and armadillo (ARM) repeats and the C-terminal ARM repeat domain, which includes a positively charged groove. We showed that all C-terminal ARM repeats are essential for patch formation and that this function requires arginine residue at position 736. By applying SAXS to polydisperse SAUL1 systems, the oligomerization of SAUL1 is detectable, with SAUL1 tetramers being the most prominent oligomers at higher concentrations. The oligomerization domain consists of the N-terminal U-box and some N-terminal ARM repeats. Deleting the U-box resulted in the promotion of the SAUL1 tethering function. Our findings indicate that structural changes in SAUL1 may be fundamental to its function in forming patches at the plasma membrane. 相似文献
109.
Romina Combi Maria Salsone Chiara Villa Luigi Ferini-Strambi 《International journal of molecular sciences》2021,22(8)
Dementia with Lewy bodies (DLB) is one of the most common causes of dementia and belongs to the group of α-synucleinopathies. Due to its clinical overlap with other neurodegenerative disorders and its high clinical heterogeneity, the clinical differential diagnosis of DLB from other similar disorders is often difficult and it is frequently underdiagnosed. Moreover, its genetic etiology has been studied only recently due to the unavailability of large cohorts with a certain diagnosis and shows genetic heterogeneity with a rare contribution of pathogenic mutations and relatively common risk factors. The rapid increase in the reported cases of DLB highlights the need for an easy, efficient and accurate diagnosis of the disease in its initial stages in order to halt or delay the progression. The currently used diagnostic methods proposed by the International DLB consortium rely on a list of criteria that comprises both clinical observations and the use of biomarkers. Herein, we summarize the up-to-now reported knowledge on the genetic architecture of DLB and discuss the use of prodromal biomarkers as well as recent promising candidates from alternative body fluids and new imaging techniques. 相似文献
110.
Emmanuel Anane Annina Sawatzki Peter Neubauer Mariano Nicolas Cruz-Bournazou 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2019,94(2):516-526
The cover image is based on the Research Article Modelling concentration gradients in fed-batch cultivations of E. coli - towards the flexible design of scale-down experiments by Emmanuel Anane et al., DOI: 10.1002/jctb.5798 .