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Acta Metallurgica Sinica(English Letters) 2022年第10期35卷 1583-1590页

作者： Huan li Shuai Zeng Yong-Kang Zhou hai-long li Hong-Wei Zhang hai-Feng Zhang Zheng-Wang Zhu Shi-Changxu Innovation Center for Advanced MaterialsInstitute of Metal Research Chinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei230026China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

Superelasticity has been widely used in various *** elastic limit simultaneously with large superelasticity is urgent in the critical *** this study,we have employed the high entropy alloy(HEA)concept to develop a new TiHfNiFe-Nb eutectic HEA(EHEA)based on the TiNi-Nb eutectic *** results show the directional catkin-like microstructure with the fiber eutectic in the center and the lamella eutectic in the outside form along the directional solidification direction when the growth rate is 60 mm/*** corresponding specimens display the high strength of 1409 MPa and superelasticity of 3.1%in tension at room temperature,which is attributed to the synergetic effect of high entropy,preferred orientation,ordered body-centered cubic(B2)phase and disordered body-centered cubic phase in the eutectic *** work sheds light on designing the high-performance superelastic function materials with EHEAs.

关键词： High-entropy alloy Eutectic alloy Directional solidification Superelasticity Tensile strength

Effect of milling process on the core-shell structures and dielectric properties of fine-grained BaTiO_3-based X7R ceramic materials

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International Journal of Minerals,Metallurgy and Materials 2009年第3期16卷 345-348页

作者： Tian Wang Xiao-hui Wang hai Wen long-tu li State Key Laboratory of New Ceramics and Fine Processing Department of Materials Science and Engineering Tsinghua University Beijing 100084 China

Fine-grained BaTiO3-based X7R ceramic materials were prepared and the effects of milling process on the core-shell structures and dielectric properties were investigated using scanning electron microscope, transmission electron microscope, and energy dispersive spectroscopy （EDS）. As the milling time extends, the dielectric constant of the ceramics increases, whereas the temperature coefficient of capacitance at 125℃ drops quickly. The changes in dielectric properties are considered relevant to the microstructure evolution caused by the milling process. Defects on the surface of BaTiO3 particles increase because of the effects of milling process, which will make it easier for additives to diffuse into the interior grains. As the milling time increases, the shell region gets thicker and the core region gets smaller; however, EDS results show that the chemical inhomogeneity between grain core and grain shell becomes weaker.

关键词： fine-grain barium titanate core-shell structure milling process microstructure capacitor

Estimating submarine groundwater discharge and associated nutrient inputs into Daya Bay during spring using radium isotopes

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Water Science and Engineering 2018年第2期11卷 120-130页

作者： Jing-yan Gao Xue-jing Wang Yan Zhang hai-long li School of Environment Harbin Institute of Technology School of Environmental Science and Engineering Southern University of Science and Technology School of Water Resources and Hydropower Engineering Wuhan University State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences

Daya Bay, a semi-enclosed bay in the South China Sea, is well known for its aquaculture, agriculture, and tourism. In recent years, many environmental problems have emerged, such as the frequent(almost yearly) occurrence of harmful algal blooms and red tides. Therefore,investigations of submarine groundwater discharge(SGD) and associated nutrient inputs to this bay have important theoretical and practical significance to the protection of the ecological system. Such a study was conducted using short-lived radium isotopes ^(223)Ra and ^(224)Ra. The estimated SGD fluxes were 2.89 × 10~7 m^3/d and 3.05 × 10~7 m^3/d based on ^(223)Ra and ^(224)Ra, respectively. The average SGD flux was about 35 times greater than that of all the local rivers. The SGD-associated dissolved inorganic nitrogen(DIN) and dissolved inorganic phosphorus(DIP)fluxes ranged from 1.95 × 10~6 to 2.06 × 10~6 mol/d and from 5.72 × 10~4 to 6.04 × 10~4 mol/d, respectively. The average ratio of DIN to DIP fluxes in SGD was 34, much higher than that in local rivers(about 6.46), and about twice as large as the Redfield ratio(16). Our results indicate that SGD is a significant source of nutrients to the bay and may cause frequent occurrence of harmful algal blooms. This study provides baseline data for evaluating potential environmental effects due to urbanization and economic growth in this region.

关键词： Submarine groundwater discharge(SGD) Radium isotopes Radium mass balance model SGD-associated nutrient fluxes Daya Bay

Numerical Analysis of Artificial Electron Heating Effects on Polar Mesospheric Winter Echoes

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Journal of Electronic Science and Technology 2020年第3期18卷 287-295页

作者： Safi Ullah hai-long li Abdur Rauf Lu-Yao Fu Mao-Yan Wang lin Meng School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054

In this paper,an analytical model is used to analyze the modulated polar mesospheric winter echoes(PMWE).The winter parameters were introduced to simulate the effects of different parameters during the artificial electron heating of *** important role of the charged dust particle in the creation of PMWE is confirmed *** is found that during the heating of PMWE,the increases of the dust size,dust charge,electron temperature,initial electron density,and ion-neutral collision frequency cause the increase of the electron density irregularity,and hence the PMWE ***,with increasing the dust density,the electron density irregularity and the PMWE strength decrease.

关键词： Artificial ionospheric heating electron density irregularities polar mesospheric winter echoes(PMWE) space plasma physics(numerical simulation)

Synchronization of High-order Discrete-time linear Complex Networks with Time-varying Delays

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Journal of Harbin Institute of Technology(New Series) 2014年第3期21卷 46-51页

作者： hai-long li Jian-Xiang Xi Yao-Qing Cao Duo-Sheng Wu Xi'an Research Institute of High Technology

Synchronization of high-order discrete-time complex networks with undirected topologies is studied and the impacts of time delays are investigated. Firstly,by the state decomposition,synchronization problems are transformed into asymptotic stability ones of multiple lower dimensional time-delayed subsystems. Then,linear matrix inequality( LMI) criteria for synchronization are given,which can guarantee the scalability of complex networks since they only include three LMI constraints independent of the number of agents. Moreover,an explicit expression of the synchronization function is presented,which can describe the synchronization behavior of all agents in complex networks. Finally,a numerical example is given to demonstrate the theoretical results,where it is shown that if the gain matrices of synchronization protocols satisfy LMI criteria for synchronization,synchronization can be achieved.

关键词： synchronization complex network time-varying delay linear matrix inequality

Therapeutic time window of flurbiprofen axetil＇s neuroprotective effect in a rat model of transient focal cerebral ischemia

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Chinese Medical Journal 2008年第24期121卷 2572-2577页

作者： WANG Chen liU Jun-le SANG Han-fei LU Yan DONG hai-long XIONG li-ze Department of Anesthesiology Xijing Hospital Fourth Military Medical University Xi'an Shaanxi 710032 China

Background The neuroprotective effect of the cyclooxygenase （COX） inhibitor has been demonstrated in acute and chronic neurodegenerative processes. But its function under cerebral ischemic conditions is unclear. This study was designed to evaluate the neuroprotective efficacy of emulsified flurbiprofen axetil （FA, COX inhibitor） and its therapeutic time window in a model of transient middle cerebral artery occlusion （MCAO） in rats. Methods Forty-eight male SD rats were randomly assigned into six groups （n=8 in each group）; three FA groups, vehicle, sham and ischemia/reperfusion （I/R） groups. Three doses of FA （5, 10 or 20 mg/kg, intravenous infusion） were administered just after cerebral ischemia/reperfusion （I/R）. The degree of neurological outcome was measured by the neurologic deficit score （NDS） at 24, 48 and 72 hours after I/R. Mean brain infarct volume percentage （MBIVP） was determined with 2,3,5-triphenyltetrazolium chloride （TTC） staining at 72 hours after I/R. In three other groups （n=8 in each group）, the selected dosage of 10 mg/kg was administrated intravenously at 6, 12 and 24 hours after I/R. Results The three different doses of FA improved NDS at 24, 48 and 72 hours after I/R and significantly reduced MBIVP. However, the degree of MBIVP in the FA 20 mg/kg group differed from that in FA 10 mg/kg group. Of interest is the finding that the neuroprotective effect conferred by 10 mg/kg of FA was also observed when treatment was delayed until 12-24 hours after ischemia reperfusion. Conclusion COX inhibitor FA is a promising therapeutic strategy for cerebral ischemia and its therapeutic time window could last for 12-24 hours after cerebral ischemia reperfusion, which would help in lessening the initial ischemic brain damage.

关键词： cerebral ischemia flurbiprofen axetil neuroprotection neurologic deficit score therapeutic time window

Typical endoscopic appearance accurately predicts sporadic fundic gland polyps： a retrospective study of 47 771 endoscopies

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Chinese Medical Journal 2013年第15期126卷 2984-2986页

作者： CAO hai-long SONG Shu-li YANG Bo-li ZHANG Zhi-hua ZHANG Hui QU Rui WANG Bang-mao Tianjin Med Univ Dept Gastroenterol & Hepatol Gen Hosp Tianjin 300052 Peoples R China Cangzhou Peoples Hosp Dept Gastroenterol & Hepatol Cangzhou 061000 Heibei Peoples R China Anhui Med Univ Dept Epidemiol Hefei 230032 Anhui Peoples R China

Sporadic fundic gland polyps （FGPs） account for 0.8%- 1.9% of all gastric polyps and are observed in patients undergoing esophagogastroduodenoscopy （EGD） in whom they account for more than 50% of all gastric polyps. The prevalence is increasing in recent years possibly due to decreased Helicobacter pylori （1t. pylori） infection rate and long-term proton pump inhibitor use. Generally, sporadic FGPs are assumed to be benign polyps with no risk of malignant transformation. We evaluated the feasibility of predicting sporadic FGPs based on typical endoscopic appearance in a large database of 47 771 endoscopies.

关键词： fundic gland polyps stomach neoplasms dysplasia endoscopy, gastrointestinal

Novel Coil Winding Method to Realize Pot Heated Evenly

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Journal of Electronic Science and Technology 2015年第2期13卷 107-111页

作者： Mao-Yan Wang hai-long li Meng Zhang Zhi-Tao Xu Cui-lin Zhong Jun Xu School of Physical Electronics University of Electronic Science and Technology of China 41st Institute of China Electronics Technology Group Corporation Centre of Integrated Electronics Shenzhen Institutes of Advanced TechnologyChinese Academy of Sciences

To solve the problem about the inhomogeneous thermal effect of pot heated by coils along the circumference, a novel coil winding method is proposed and compared with the general winding method in the paper. First, based on the Biot-Savart law and Ampere＇s rule, the magnetic induction generated by a straight current carrying conductor and a current loop is discussed, respectively. Then the novel coil winding method is developed by adjusting the location of inhomogeneous joints. The joints are periodically scattered along the circumferential direction and symmetrically designed around the central *** results show that the quite non-uniform temperature in the base of pot at the circular direction is effectively improved by using the proposed winding method. The potential danger produced by high temperature at some region of coils plate is *** is energy-efficient and safe for residential appliances.

关键词： winding inhomogeneous straight joints periodically scattered carrying circular adjusting heating

Clinical significance and influencing factors of linked color imaging technique in real-time diagnosis of active Helicobacter pylori infection

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Chinese Medical Journal 2019年第20期132卷 2395-2401页

作者： li Wang Xiang-Chun lin hai-long li Xue-Song Yang Lei Zhang Xin li Peng Bai Yan Wang Xue Fan Yi-Ming Ding Ding Department of Gastroenterology Peking University International HospitalBeijing 102206China

Background:Determining the Helicobacter pylori (H. pylori) infection state during the gastroscopic process is important but still challenging. The linked color imaging (LCI) technique might emphasize the mucosal color change after H. pylori infection, which might help the diagnosis. In the present study, we aimed to compare the LCI technique with traditional white light imaging (Wli) endoscopy for diagnosing active H. pylori ***:We collected and analyzed gastroscopic images from 103 patients in our hospital from November 2017 to March 2018, including both LCI and Wli modes. All images were randomly disordered and independently evaluated by four endoscopists who were blinded to the H. pylori status of patients. In addition, the H. pylori state was determined by both rapid urease test and pathology staining. The sensitivity, specificity, positive prediction value (PPV), and negative prediction value (NPV) were calculated for the detection of H. pylori infection. Moreover, the kappa value and interclass correlation coefficient (ICC) were used to evaluate the inter-observer variety by SPSS 24.0 ***:Of the 103 enrolled patients, 27 of them were positive for H. pylori infection, while the 76 patients were negative. In total, 388 endoscopic images were selected, including 197 Wli and 191 LCI. The accuracy rate for H. pylori evaluation in the corpus LCI group was significantly higher than other groups (81.2% vs. 64.3%-76.5%, χ2 = 34.852, P li (0.433-0.554 vs. 0.331-0.554). Consistently, the ICC value was also higher with LCI than with Wli (0.501 [95% CI: 0.429-0.574]

关键词： Helicobacter pylori Image enhancement technique linked color imaging Real-time diagnosis

Spring Cold Bias of SST and Minimal Wind Mixing in the Equatorial Pacific Cold Tongue

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Atmospheric and Oceanic Science Letters 2010年第6期3卷 342-346页

作者： liN Peng-Fei liU hai-long li Chao ZHANG Xue-Hong State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of AtmosphericPhysics Chinese Academy of Sciences Beijing 100029 China

The authors investigate the relationship between bias in simulated sea surface temperature （SST） in the equatorial eastern Pacific cold tongue during the boreal spring as simulated by an oceanic general circulation model （OGCM） and minimal wind mixing （MWM） at the surface. The cold bias of simulated SST is the greatest during the boreal spring, at approximately 3℃. A sensi- tivity experiment reducing MWM by one order of magnitude greatly alleviates cold biases, especially in March-April. The decrease in bias is primarily due to weakened vertical mixing, which preserves heat in the uppermost layer and results in warmer simulated SST. The reduction in vertical mixing also leads to a weak westward current in the upper layer, which further contributes to SST warming. These findings imply that there are large uncertainties about simple model parameters such as MWM at the oceanic surface.

关键词： cold biases the equatorial Pacific cold tongue the minimal wind mixing