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Power flow analysis in a hybrid phononic crystal structure

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Chinese Physics B 2018年第3期27卷 357-361页

作者： Hanbei Guo qiang Li Liubin Zhou lei qiang The Second Ship-Designing Institute of Wuhan Wuhan 430064 China

To reveal the energy transmission through a hybrid phononic crystal structure, power flow analysis is carried out in this paper. Hysteretic damping having significant relationship with power flow is added and corresponding theoretical formulas of the dispersion relation are derived. Besides, the power flow in the hybrid structure is calculated by using the finite element method. The results show that as the damping increases, the boundaries of the band gaps become smoother and dimmer, i.e., broader width. With the increase of damping, the power flow is lowered at the resonance frequencies, while slightly increases near the resonance frequencies. The power flow maps manifest energy distribution in the hybrid structure within and out of the band gaps, which can be exploited in the optimization of the structure design.

关键词： energy transmission hybrid phononic crystal power flow hysteretic damping

Effects of Sm content on crystallized structure and magnetic properties of Co80-xSmxb20 amorphous alloys

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Journal of Iron and Steel Research International 2020年第4期27卷 471-476页

作者： lei-qiang Lai Yan-hui Li Feng Bao Wei Zhang Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian 116024LiaoningChina

The formation,thermal stability,crystallized structure,and magnetic properties of melt-spun Co80-xSmxB20(x=0–20)amorphous alloys have been investigated.A single amorphous phase is formed for the alloys with x=0–*** first crystallization temperature gradually increases from 670 to 955 K as x increases from 0 to 10,and decreases to 836K when x=*** optimum annealing,the nanocomposite structure consisting of SmCo12B6+fcc-Co+Sm2Co17 phases is formed for the alloys with x=5 and 7.5,and SmCo12B6+Sm2Co17+SmCo3,SmCo12B6+Sm2Co17+SmCo4B,and SmCo12B6+SmCo4B phases are formed for the alloys with x=10,12.5,and 15,*** coercivity of the annealed alloys increases remarkably from 103.5 to 1249.4 kA m^-1 as x increases from 5 to 15,while the magnetization at the applied field of 2.0T decreases from 0.51 to *** improved magnetic hardness with rising Sm content is attributed to the formation of the hard magnetic phases with higher magnetocrystalline anisotropy and the increase in their volume fraction.

关键词： Co-Sm-B alloy Melt-spun Amorphous alloy Crystallized structure Magnetic property

AN IMPROVED NONLINEAR CLOSED GRAPH THEOREM

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Applied Mathematics(A Journal of Chinese Universities) 2007年第2期22卷 226-228页

作者： lei qiang Li Ronglu Department of Mathematics Harbin Institute of Technology Harbin 150006 China

In this paper, a new nonlinear closed graph theorem is established, whose result improves substantially a recent-known important conclusion.

关键词： closed graph Fréchet space continuity

Baeyer-Villiger oxidation of ketones with hydrogen peroxide catalyzed by Sn-aniline complex

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Chinese Chemical Letters 2007年第1期18卷 4-6页

作者： Qing Hua Zhang Shou Feng Wang Zi qiang lei Key Laboratory of Polymer Materials of Gansu Province College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 China

Sn-aniline complex was prepared by a simple procedure. Cyclic and acyclic ketones were oxidized into lactones or esters with very high selectivity and yield with 30% hydrogen peroxide in the presence of Sn-aniline com... 详细信息

关键词： Baeyer-Villiger oxidation Sn-aniline complex Ketone oxidation Hydrogen peroxide

LOW-POTENTIAL ELECTROSYNTHESIS OF CONDUCTING AND ELECTROACTIVE OLIGOCATECHOLBORANE WITH BLUE LIGHT-EMITTING PROPERTIES

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Chinese Journal of Polymer Science 2013年第1期31卷 159-170页

作者： Bao-yang Lu Shuai Chen lei-qiang Qin Yao Huang 徐景坤 School of Pharmacy Jiangxi Science & Technology Normal University School of Materials Science & Engineering Shandong University

Novel conducting oligocatecholborane （OCOB） with electrical conductivity of 3.73 × 10^-2 S cm-1 was successfully synthesized by low-potential electropolymerization of catecholborane （COB） in boron trifluoride diethyl etherate at 0.70 V versus Ag/AgC1. FT-IR and ^1H-NMR spectra, together with the computational results, proved that COB was polymerized through the coupling at C（4） and C（5} positions and the reactive B- H bond was stable during the electrochemical polymerization. The resulting product was mainly composed of oligomers with short chain lengths by GPC and mass spectral results. The as-formed OCOB film showed good electrochemistry in monomer-free electrolytes with the electrochromic property from opaque blue to sap green. Fluorescence studies indicated that soluble OCOB can emit bright blue light under excitation of 365 nm UV light with the maximum emission at 396 nm and a fluorescence quantum yield of 0.21. The deposited OCOB also exhibited favorable thermal stability and smooth and compact morphology even at high magnifications.

关键词： Conducting polymers Electrochemical polymerization Catecholborane Boron trifluoride diethyl etherate Fluorescence

Cooperated Bayesian algorithm for distributed scheduling problem

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Frontiers of Electrical and Electronic Engineering in China 2006年第3期1卷 251-254页

作者： qiang lei XIAO Tian-yuan Department of Automation Tsinghua UniversityBeijing 100084China

This paper presents a new distributed Bayesian optimization algorithm(BOA)to overcome the efficiency problem when solving NP scheduling *** pro-posed approach integrates BOA into the co-evolutionary schema,which builds up a concurrent computing environ-ment.A new search strategy is also introduced for local op-timization *** integrates the reinforcement learning(RL)mechanism into the BOA search processes,and then uses the mixed probability information from BOA(post-probability)and RL(pre-probability)to enhance the cooperation between different local controllers,which im-proves the optimization ability of the *** ex-periment shows that the new algorithm does better in both optimization(2.2%)and convergence(11.7%),compared with classic BOA.

关键词： statistic optimization distributed scheduling Bayesian networks data mining

Salvianolate increases heat shock protein expression in a cerebral ischemia-reperfusion injury model

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Neural Regeneration Research 2013年第25期8卷 2327-2335页

作者： Jinnan Zhang Wei Lu qiang lei Xi Tao Hong You Pinghui Xie Department of Neurology Second Xiangya HospitalCentral South University

Stroke remains a worldwide health problem. Salvianolate exerts a protective effect in various mi- crocirculatory disturbance-related diseases, but studies of the mechanisms underlying its protective action have mainly focused on the myocardium, whereas little research has been carried out in brain tissue following ischemia-reperfusion. We assessed the neuroprotective effects of salvianolate in a rat model of cerebral ischemia-reperfusion injury induced using the suture method. At onset and 24 and 48 hours after reperfusion, rats were intraperitoneally injected with salvianolate （18 mg/kg） or saline. Neurological deficit scores at 72 hours showed that the neurological functions of rats that had received salvianolate were significantly better than those of the rats that had received saline. 2,3,5-Triphenyltetrazolium chloride was used to stain cerebral tissue to determine the extent of the infarct area. A significantly smaller infarct area and a significantly lower number of apoptotic cells were observed after treatment with salvianolate compared with the saline treatment. Expression of heat shock protein 22 and phosphorylated protein kinase B in ischemic brain tissue was significantly greater in rats treated with salvianolate compared with rats treated with saline. Our findings suggest that salvianolate provides neuroprotective effects against cerebral ischemia-reperfusion injury by upregulating heat shock protein 22 and phosphorylated protein kinase B expression.

关键词： neural regeneration traditional Chinese medicine brain injury salvianolic acid B salvianolate heatshock protein 22 protein kinase B cerebral ischemia-reperfusion injury apoptosis neuroprotection neuroregeneration

Distinction between short-segment Barrett's esophageal and cardiac intestinal metaplasia

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World Journal of Gastroenterology 2005年第40期11卷 6360-6365页

作者： Gui-Sheng Liu Jun Gong Peng Cheng Jun Zhang Ying Chang lei qiang Department of Gastroenterology the Second Hospitalof Xi'an Jiaotong University Xi'an 710004 Shaanxi ProvinceChina Department of Pathology the Second Hospital of Xi'an Jiaotong University Xi'an 710004 Shaanxi Province China

AIM： To investigate the roles of mucin histochemistry, cytokeratin 7/20 （CK7/20） immunoreactivity, clinical characteristics and endoscopy to distinguish short- segment Barrett＇s esophageal （SSBE） from cardiac intestinal metaplasia （CIM）. METHODS： High iron diamine/Alcian blue （HID/AB） mucin-histochemical staining and immunohistochemical staining were used to classify intestinal metaplasia （IN） and to determine CK7/20 immunoreactivity pattern in SSBE and CIM, respectively, and these results were compared with endoscopical diagnosis and the positive rate of gastroesophageal reflux disease （GERD） symptoms and H pylori infection. Long-segment Barrett＇ s esophageal and IM of gastric antrum were designed as control. RESULTS： The prevalence of type III IM was significantly higher in SSBE than in CIM （63.33% vs 23.08%, P〈0.005）. The CK7/20 immunoreactivity in SSBE showed mainly Barrett＇s pattern （76.66%）, and the GERD symptoms in most cases which showed Barrett＇ s pattern were positive, whereas H pylori infection was negative. However, the CK7/20 immunoreactivity in CIM was gastric pattern preponderantly （61.54%）, but there were 23.08% cases that showed Barrett＇s pattern. H pylori infection in all cases which showed gastric pattern was significantly higher than those which showed Barrett＇ s pattern （63.83% vs 19.30%, P〈0.005）, whereas the GERD symptoms in gastric pattern were significantly lower than that in Barrett＇s pattern （21.28% vs 85.96%,P〈O.O05）. CONCLUSION： Distinction of SSBE from CIM should not be based on a single method; however, the combination of clinical characteristics, histology, mucin histochemistry, CK7/20 immunoreactivity, and endoscopic biopsy should be applied. Type III IM, presence of GERD symptoms, and Barrett＇s CK7/20 immunoreactivity pattern may support the diagnosis of SSBE, whereas non-type III IM, positive H pylori infection, and gastric CK7/20 immunoreactivity pattern may imply CIM.

关键词： Short-segment Barrett's esophageal Cardiacintestinal metaplasia Cytokeratin 7/20 immunoreactivity

A Stoneley wave method to detect interlaminar damage of metal layer composite pipe

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Frontiers of Mechanical Engineering 2015年第1期10卷 89-94页

作者： Bing LI lei qiang Tong LU Xu GENG Minghang LI State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Xi'an 710049 China

The interlaminar defect is a major form of damage in metal layer composite pipes which are widely used in petroleum and chemical industry. In this paper, a Stoneley wave method is presented to detect interlaminar damage in laminated pipe structure. Stoneley wave possesses some good characteristics, such as high energy and large displacement at the interface and non-dispersive in the high-frequency, so the sensitivity of detecting interlaminar damage can be improved and the higher frequency can be used in damage detection compared with Lamb waves. Additionally, as the frequency increases, the wavelength of the Stoneley wave reduces. Thus, its ability to detect small defects at the interface is enhanced. Finite element model of metal layer composite pipe with interlaminar damage is used to simulate wave propagation of Lamb waves and Stoneley wave, respectively. The damage location is calculated by using the Stoneley wave signal obtained from finite element model, and then the results are compared with the actual damage locations. The simulation examples demonstrate that the Stoneley wave method can better identify the interlaminar damage in laminated pipe structure compared with Lamb waves.

关键词： Stoneley wave interlaminar damage metallaminated pipe