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Journal of Thermal Science 2011年第4期20卷 304-311页

作者： jun li hao SUN Jinshan WANG Zhenping FENG Institute of Turbomachinery Xi＇an Jiaotong University Xi＇an 710049 CHINA

The steady and unsteady leakage flow and heat transfer characteristics of the rotor blade squealer tip were conducted by solving Reynolds-Averaged Navier-Stokes （RANS） equations with k-co turbulence model. The first stage of GE-E3 engine with squealer tip in the rotor was adopted to perform this work. The tip clearance was set to be 1% of the rotor blade height and the groove depth was specified as 2% of the span. The results showed that there were two vortexes in the tip gap which determined the local heat transfer characteristics. In the steady flow field, the high heat transfer coefficient existed at several positions. In the unsteady case, the flow field in the squealer tip was mainly influenced by the upstream wake and the interaction of the blades potential fields. These unsteady effects induced the periodic variation of the leakage flow and the vortexes, which resulted in the fluctuation of the heat transfer coefficient. The largest fluctuation of the heat transfer coefficient on the surface of the groove bottom exceeded 16% of the averaged value on the surface of the squealer tip.

关键词： Gas Turbine Blade Squealer Tip Leakage Flow Heat Transfer Numerical Simulation

Stability of Two-Component Bose-Einstein Condensates in Bessel Optical Lattices

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Communications in Theoretical Physics 2008年第6期49卷 1519-1526页

作者： CHEN Hai-jun li hao-Cai XUE Ju-Kui College of Physics and Electronics Engineering Northwest Normal University Lanzhou 730070 China

The stability of the ground state of two-component Bose-Einstein condensates （BEGs） loaded into the central well of an axially symmetric Bessel lattices （BLs） potential with attractive or repulsive atoms interactions is studied using the time-dependent Gross-Pitaevskii equation （GPE）. By using the variational method, we find that stable ground state of two-component BEGs can exist in BLs. The BLs＇s depth and the intra-species atom interaction play an important role in the stability of ground state. The collapse of two-component BEGs in BLs is also studied and a collapse condition for trapped two-component BEGs is obtained. It is shown that the two-component BEGs exhibit rich collapse dynamics. That is, the two-component BEGs can collapse in the system with both intra- and inter-attractive, or with intra-attractive and inter-repulsive, or with intra-repulsive and inter-attractive atom interactions. Furthermore, the control of the collapse of the two-component BEGs in BLs is discussed in detail. The stability diagram of the ground state in parameter space is obtained. The results show that the collapse of two-component BEGs can be controlled by temporal modulation of the atom interaction.

关键词： two-component Bose-Einstein condensates Gross-Pitaevskii equation Bessel optical lattice ground state

Subclavian steal syndrome associated with Sjogren's syndrome: A case report

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World Journal of Clinical Cases 2021年第27期9卷 8171-8176页

作者： li-jun hao Jing Zhang Muhammad Naveed Kai-Yan Chen Ping-Xi Xiao Department of Cardiology Sir Run Run HospitalNanjing Medical UniversityNanjing 211166Jiangsu ProvinceChina Department of Clinical Pharmacology Nanjing Medical UniversityNanjing 211166Jiangsu ProvinceChina Department of Clinical Medicine Nanjing Medical UniversityNanjing 211166Jiangsu ProvinceChina

BACKGROUND Subclavian steal syndrome(SSS)caused by Sjogren's syndrome is rare,especially for elderly patients with risk factors for *** current report presents the uncommon etiology and treatment of SSS,aiming to improve doctor’s clinical *** SUMMARY A 69-year-old man was diagnosed with hypertension and acute cerebral infarction presenting with left upper limb weakness and pain even gradually aggravating to left limb hemiplegia 30 years *** was managed with antihypertensive and antithrombotic therapy;however,his condition was recurrent,and he never had any further *** was found that the difference of the bilateral upper arm systolic pressure was over 20 mmHg,and Doppler examination showed that the blood flow of the left vertebral artery was reversed,suggesting *** tests revealed a benign lymphoepithelial lesion in salivary gland tissue,confirming the Sjogren's *** The patient was found to have hypertension when he was 33 years old,and the blood pressure of both sides was asymmetric,which was *** patient's symptoms of dizziness and upper limb weakness were misdiagnosed as general cerebral *** is necessary to test the aorta computed tomography angiography to prove secondary hypertension factors such as Sjogren's syndrome.

关键词： Subclavian steal syndrome Sjogren's syndrome limb Case report

Simulation Research of Transient Over-voltage on High-voltage Shunt Capacitor Banks

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高压电器 2011年第9期47卷 37-43页

作者： HU Quan-wei ZHOU Xing-xing SI Wen-rong ZHANG Yang li jun-hao li Yan-ming Power Equipment State Key Laboratory of Electrical Insulation Xi'an Jiaotong University Xi'an 710049 China Electric Power Research Institute of East China Shanghai 200437 China Yichang Power Supply Company Yichang 443000 China

With the development of power systems,a large number of shunt capacitors are used to improve power quality in the distribution *** shunt capacitor banks are operated much frequently,as a result,the capacitor banks will bear large numbers of over-voltage *** the over-voltage exceeds certain amplitude,the capacitor will be *** paper aims at the capacitor banks in the 35 kV side of Shanghai Xu-xing 500 kV substation,and applies ATP-EMTP to simulate the over-voltages generated by operating the switches under different angles of the ***,according to the results of simulation and theoretical analysis,a best choice(*** of the source) to switch on capacitor banks is *** this case the over-voltage on the capacitor will be limited to lowest.

关键词： capacitor banks operating over-voltage EMTP simulation

Protective effect of omeprazole on gastric mucosal of cirrhotic portal hypertension rats

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Asian Pacific Journal of Tropical Medicine 2014年第5期7卷 402-406页

作者： Wei Gao Hai-Ying li li-Xin Wang li-jun hao Jian-li Gao Rong-Juan Zheng Chun-Jiang Cai Yan-ling Si Department of Gastroenterology Tangshan Workers' Hospital Department of Spleen and Stomach Tangshan TCM Hospital

Objective:To observe the protective effect of omeprazole on gastric mucosal of cirrhotic portal hypertension ***:All rats were randomly divided into normal control group,cirrhosis and treatment *** was used to establish rat model of cirrhotic portal *** necrotic tissue of gastric mucosa ulcer focus,degree of neutrophils infiltration at the ulcer margin,portal pressure,portal venous flow,abdominal aortic pressure,abdominal aortic blood flow at front end,gastric mucosal blood flow（GMBF）,glycoprotein（GP）of gastric mucosa,basal acid secretion,H’ back-diffusion,gastric mucosal damage index,NO,prostaglandin E2（PGE2） and tumor necrosis factor-α（TNF-α） were determined respectively,and the pathological changes of gastric mucosa were also observed by ***:Compared with cirrhosis group and the control group,the ulcer bottom necrotic material,gastric neutrophil infiltration and UI of the treatment group were all decreased significantly（P<0.01）,GMBF value,GP values,serum NO,PGE2,TNF- a were all significantly ***:Omeprazole has an important protective effect on gastric mucosal and it can increase gastric mucosal blood flow and related to many factors.

关键词： Omeprazole Cirrhotic portal hypertension Gastric mucosal injury Prostaglandins Tumor necrosis factor-alpha

Competitive virus and host RNAs： the interplay of a hidden virus and host interaction

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Protein & Cell 2014年第5期5卷 348-356页

作者： Changfei li jun Hu junli hao Bao Zhao Bo Wu Lu Sun Shanxin Peng George F. Gao Songdong Meng CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of Microbiology Chinese Academy of Sciences(CAS) Beijing 100101 China

During virus infection, viral RNAs and mRNAs function as blueprints for viral protein synthesis and possibly as pathogen-associated molecular patterns （PAMPs） in innate immunity. Here, considering recent research progress in microRNAs （miRNAs） and competitive endogenous RNAs （ceRNAs）, we speculate that viral RNAs act as sponges and can sequester endogenous miRNAs within infected cells, thus cross-regulating the stability and translational efficiency of host mRNAs with shared miRNA response elements. This cross-talk and these reciprocal interactions between viral RNAs and host mRNAs are termed ＂competitive viral and host RNAs＂（cvhRNAs）. We further provide recent experimental evidence for the existence of cvhRNAs networks in hepatitis B virus （HBV）, as well as Her- pesvirus saimiri （HVS）, lytic murine cytomegalovirus （MCMV） and human cytomegalovirus （HCMV） infec- tions. In addition, the cvhRNA hypothesis also pre- dicts possible cross-regulation between host and other viruses, such as hepatitis C virus （HCV）, HIV, influenza virus, human papillomaviruses （HPV）. Since the interaction between miRNAs and viral RNAs also inevitably leads to repression of viral RNA function, we speculate that virus may evolve either to employ cvhRNA networks or to avoid miRNA targeting for optimal fitness within the host. CvhRNA networks may therefore play a fundamental role in the regulation of viral replication, infection establishment, and viral pathogenesis.

关键词： cvhRNAs virus RNAs host mRNAs,miRNA response element ceRNAs

Aortic reoperation in a patient with Loeys-Dietz syndrome

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Chinese Medical Journal 2014年第12期127卷 2398-2399页

作者： Wang Chunsheng li jun Lai hao Sun Yongxin Guo Changfa Yin Kanhua Zhu Kai Department of Cardiac Surgery Shanghai Institute of Cardiovascular DiseaseZhongshan HospitalFudan UniversityShanghai 200032China

Loeys-Dietz syndrome （LDS, OMIM #609192） is a recently recognized connective tissue disorder with clinical characteristics similar to Marfan syndrome. Aggressive aortic pathologies in LDS makes timely diagnosis and surgical intervention crucial compared to other genetic syndromes. We report a young man with LDS confirmed by genetic testing who twice underwent surgical operations to repair aortic aneurysm.

关键词： Loeys-Dietz syndrome mutation receptors, transforming growth factor-beta aortic aneurysm

缓释尿素对土壤微生物氮素生理群、理化性质及辣椒产量的影响

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甘肃农业大学学报 2017年第4期52卷 58-66页

作者：李昊骏曹莉秦舒浩甘肃农业大学园艺学院甘肃兰州730070

【目的】通过田间试验,研究了缓释尿素对土壤微生物氮素生理群、理化性质及辣椒产量的影响.【方法】以‘陇椒2号’为供试材料,采用普通尿素(释放期0d)和缓释尿素(释放期90和180d)与施氮量(450kg/hm^2、400kg/hm^2、350kg/hm^2、300kg/hm... 详细信息

【目的】通过田间试验,研究了缓释尿素对土壤微生物氮素生理群、理化性质及辣椒产量的影响.【方法】以‘陇椒2号’为供试材料,采用普通尿素(释放期0d)和缓释尿素(释放期90和180d)与施氮量(450kg/hm^2、400kg/hm^2、350kg/hm^2、300kg/hm^2)双因素交互试验.【结果】在同一施氮水平,释放期为180d的缓释尿素(D180)可显著提高辣椒产量,其中处理A3B3(释放期180d、施氮量350kg/hm^2)为最优处理,产量最高,达14 540.1kg/hm^2,分别比普通尿素U和缓释尿素D90处理增产146.6%和52.1%;施氮量超过400kg/hm^2,辣椒减产明显;缓释尿素D180可使辣椒土壤保持较高数量的好气性自生固氮菌、嫌气性自生固氮菌和硝化细菌,分别比普通尿素U增加了2.6倍、6.3倍和29.2倍;在辣椒幼苗期、旺盛生长期和开花坐果期,缓释尿素和施氮量的交互作用对碱解氮、速效钾含量和土壤EC值存在极显著的影响.【结论】缓释尿素和施氮量的交互作用对辣椒土壤微生物氮素生理群及理化性质有显著影响,其中释放期180d、施氮量350kg/hm^2处理有利于提高辣椒产量及改善土壤微生物菌群.

关键词：缓释尿素辣椒氮素生理群理化性质产量

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MACTEN:新型大规模布料纹理分类框架

计算机科学 2020年第S2期47卷 258-265页

作者：李浩翔李浩君浙江工业大学教育科学与技术学院杭州310023

针对纺织品行业布料种类数多且纹理复杂导致人为区分困难的问题,引入深度学习技术,提出了融合多尺度注意力共现特征的残差纹理编码网络模型(MACTEN),并基于此实现Web端大规模布料分类系统。MACTEN主要包含注意力共现表示模块(ACM),改进... 详细信息

针对纺织品行业布料种类数多且纹理复杂导致人为区分困难的问题,引入深度学习技术,提出了融合多尺度注意力共现特征的残差纹理编码网络模型(MACTEN),并基于此实现Web端大规模布料分类系统。MACTEN主要包含注意力共现表示模块(ACM),改进的残差编码模块(REM),以及多尺度纹理编码融合模块(MTEM)。ACM使用注意力机制对不同类型的布料自适应调整纹理共现特征权重,并通过扩展共现域优化共现特征的联合分布,形成更精致的纹理共现特征;REM通过了字典学习方式,产生改进的残差编码,包含空间不变性的全局纹理信息,有效解决了布料纹理的无序表示问题。最后,MTEM同时融合多个尺度注意力纹理共现特征与级联残差纹理编码作为描述子,可以表示不同形状大小的无序布料纹理。在自建布料数据集上,MACTEN相比几种基线算法有更好的表现。此外,KTHTIPS,FMD,DTD数据集的实验结果表明,MACTEN能够泛化作为通用纹理分类算法。

关键词：布料分类深度学习纹理描述子共现特征特征融合

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基于光纤光栅的结构体裂缝三维应变传感

光子学报 2016年第12期45卷 1-5页

作者：王丽丽忻向军郝金光鲁东大学信息与电气工程学院山东烟台264025 北京邮电大学电子工程学院北京100876

利用光纤光栅的反射谱设计了一种用于混凝土纵向裂缝三维应变传感信号的检测及分析处理的方法.利用ANSYS软件自底向上采用构造法构建混凝土三维断裂模型,分析径向均匀作用力下光纤光栅三轴的应力大小,由三维受力模型拟合光栅传感器的三... 详细信息

利用光纤光栅的反射谱设计了一种用于混凝土纵向裂缝三维应变传感信号的检测及分析处理的方法.利用ANSYS软件自底向上采用构造法构建混凝土三维断裂模型,分析径向均匀作用力下光纤光栅三轴的应力大小,由三维受力模型拟合光栅传感器的三轴应变函数,给出径向作用力下x和y偏振方向谐振波长与三轴应力间的关系,并且由传输矩阵法计算三轴应力作用下光栅反射谱的变化规律;理论分析和模拟计算光纤光栅传感光谱反射峰的分裂规律.结果表明:在均匀的20N作用力下,10cm长光栅x偏振方向的波长偏移量最大值为10.1nm,y偏振方向的波长偏移量最大值为12nm,此时光纤光栅的谐振峰产生明显分裂,形成两个谐振峰,随着载荷的不断增大,两个谐振峰不断地向两边分开,反射峰的分裂点从短波长向长波方向移动,分裂出来的两个谐振峰中短波谐振峰的反射率高于长波谐振峰,但短波谐振峰的带宽小于长波谐振峰带宽;当光栅长度增加至15cm时,在相同的作用力下,光栅两个反射峰的半高宽度均增加,但两个反射峰的间距几乎不变,灵敏度达0.14nm/N.本文研究可将单根光栅结构传感器的二维传感扩展到三维传感.

关键词：光纤光栅径向作用力反射谱传输矩阵法三维应变传感