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A Hybrid Joining Technology for Aluminum/Zinc coated Steels in Vehicles

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Journal of Materials Science & Technology 2010年第9期26卷 858-864页

作者： c.y.choi d.c.Kim d.G.Nam y.d.Kim y.d.Park School of Materials Science and Engineering Pusan National UniversityBusan Advanced Welding & Joining R&d division Institute of Industrial Technology Incheon dongnam Technology Service division Korea Institute of Industrial TechnologyBusan department of Advanced Materials Engineering Dong-Eui UniversityBusan

currently,in the automotive industry,joining of the aluminum alloys with the steel is a crucial problem to be *** joining techniques including resistance spot and gas metal arc welding are not acceptable for those applications due to a number of metallurgical *** investigation was carried out to develop the hybrid joining process combining the resistance spot welding and *** this study,an attempt was made to apply hybrid process to the joining of dissimilar sheet metals,Al-Mg-Si（6000 series） alloy and low carbon steel *** process（resistance spot weld/brazing） using filler metal was found to be effective to overcome the incompatibility between aluminum alloy and *** hybrid joining process of Al alloy sheet and steel sheet did not produce acceptable bond strength,it was proved to have reasonable interfacial bond layer if the optimal process condition was applied.

关键词： Hybrid joining Aluminum alloy Steel Resistance welding Brazing

cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders

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Neural Regeneration Research 2025年第4期20卷 1079-1080页

作者： Victor V.chizhikov Igor y.Iskusnykh department of Anatomy and Neurobiology University of Tennessee Health Science CenterMemphisTNUSA

development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical *** such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in *** cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)*** cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;dal-Valle-Anton and Borrell,2022).

关键词： epithelium Figure center

characteristics of urban ozone level in Hong kong

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Journal of Environmental Sciences 2001年第1期13卷 1-7页

作者： d.y.c.LEUNG d.N.ZHANG department of Mechanical Engineering The University of Hong KongPokfulam RoadHong KongChina Research Institute of Environmental Engineering East China University of Science and TechnologyShanghai 200237China

The long term trend of ozone level in Hong Kong has been investigated. One of the characteristics of ozone level in Hong Kong is the existence of autumn maximum and summer minimum. Observations of the diurnal variation of ozone level have been made in different area categories. There are early morning peak and afternoon peak occurred in the diurnal variation, which are different from some metropolitans where only an afternoon peak is observed. A negative correlation coefficient was found between monthly ozone level with nitric oxide level. On the contra.y, there is a positive correlation between ozone and nitrogen dioxide. The positive correlation coefficient between nitric oxide and nitrogen dioxide shows that the total amount of nitric oxide emitted from a series of moving and fixed sources greatly exceeded the stoichiometric amount of ozone formed from chemical reactions of precursors and long distance transportation.

关键词： ozone urban air pollution Hong kong china

A new design of dual-constituent triangular lattice metamaterial with unbounded thermal expansion

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Acta Mechanica Sinica 2019年第3期35卷 507-517页

作者： y.c.Zhang y.J.Liang S.T.Liu y.d.Su State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China New Functional Structural design and Verification Key Laboratory of Aeronautical Technology Shenyang 110035China

Triangular lattice metamaterials composed of bi-layer curved rib elements (called the Lehman-Lakes lattice) possess unbounded thermal expansion, high stiffness and impossibility of thermal buckling, which are highly desirable in many engineering structural applications subjected to large fluctuations in temperature. However, the requirement of such lattice metamaterial is that it must be a hinged joint in order to achieve the bending deformation upon heating freely, which directly leads to poor manufacturability, especially in small dimensions. In this study, a new design of dual-constituent triangular lattice metamaterial (dTLM) with good manufacturability is proposed to achieve the identical unbounded thermal expansion. In this lattice, a special bi-layer curved rib element where layer one is partially covered by layer two is presented, where the hinge joints are not necessary because the flexural rigidity in the single-layer part is much smaller than that in the bi-layer part, and the desirable thermal bending deformation can be achieved. A sample fabricated by additive manufacturing is given in order to show the good manufacturability;simultaneously, the multifunctional performance of the tailored dTLM with zero, large positive or negative coefficient of thermal expansion (cTE) can remain excellent, as well as the Lehman-Lakes lattice. Examples illustrate that the dTLM with zero cTE has about 34.2% improvement in stiffness and meanwhile has 17% reduction in weight compared with the Lehman-Lakes lattice. The stiffness of the dTLM has a moderate reduction when achieving the same large positive or negative cTE. In addition, the thermomechanical properties of the dTLM are given by the closed-form analytical solution and their effectiveness is verified by the detailed numerical simulation.

关键词： Metamaterial Zero thermal expansion Lattice material Multifunctional design Additive manufacturing

Effect of Heat Treatment Time on dy–cu Alloy diffusion Process in dy-containing commercial Nd–Fe–B Sintered Magnets

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Acta Metallurgica Sinica(English Letters) 2018年第5期31卷 496-502页

作者： H.y.Liu G.Wang y.Hong d.c.Zeng School of Materials Science and Engineering South China University of Technology

In this paper, the grain boundary diffusion process（GBdP） using a dy70cu30（at.%） alloy as the diffusion source was performed in a commercial sintered Nd–Fe–B magnet, and the effect of heat treatment time on the microstructure and magnetic properties of the magnet was investigated in detail. For the processed magnets heat-treated at 860℃, as heat treatment time increased, the coercivity and the depth of（Nd,dy）2Fe14B core–shell structure increased first and then decreased. However, when the heat treatment time was more than 2 h, the diffusion path of dy from the dy-rich shell phase into the Nd2Fe14B grains was revealed, and a nearly homogeneous（Nd,dy）2Fe14B phase was formed, which brought on the decrease in both the depth of visible core–shell structure and the coercivity of Nd–Fe–B magnet.

关键词： Sintered Nd-Fe-B magnets Grain boundary diffusion Heat treatment time coercivity Micromagnetic simulation

chylous Ascites:A Review of Pathogenesis,diagnosis and Treatment

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Journal of clinical and translational Hepatology 2018年第1期6卷 105-113页

作者： richa Bhardwaj Haleh Vaziri Arun Gautam Enrique Ballesteros david Karimeddini George y. Wu department of Medicine Division of Gastroenterology-HepatologyUCONN HealthFarmingtonCTUSA department of Pathology and Lab Medicine UCONN HealthFarmingtonCTUSA department of diagnostic Imaging and Therapeutics UCONN HealthFarmingtonCTUSA department of Medicine Division of Gastroenterology-HepatologyUCONN HealthFarmingtonCT 06030USA

chylous ascites(cA)is a rare form of ascites that results from the leakage of lipid-rich lymph into the peritoneal *** usually occurs due to trauma and rupture of the lymphatics or increased peritoneal lymphatic pressure secondary to *** underlying etiologies for cA have been classified as traumatic,congenital,infectious,neoplastic,postoperative,cirrhotic or *** malignancy and cirrhosis account for about two-thirds of all the cases of cA in Western countries,in this article we have attempted to reclassify cA based on portal and non-portal *** diagnosis of cA is based on the distinct characteristic of the ascitic fluid which includes a milky appearance and a triglyceride level of>200 mg/*** management consists of identifying and treating the underlying disease process,dietary modification,and *** studies have also supported the use of agents such as orlistat,somatostatin,octreotide and *** and surgical interventions in the form of transjugular intrahepatic portosystemic shunt(commonly known as TIPS),peritoneal shunt,angiography with embolization of a leaking vessel,and laparotomy remain as treatment options for cases refractory to medical management.

关键词： chylous ascites Portal hypertension cirrhosis Ascitic fluid Lymphatic system

Mathematical Simulation of Evaporating Brine by Solar Radiation for the Production of Salt

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Journal of Thermal Science 1993年第2期2卷 143-151页

作者： y.Z.Zhang c.d.Li 等 dept.ofEngineeringThermophysics UniversityofScienceandTechnologyofCHinaHefeiAnhui230026china Scien

A computer simulation model of salt pan is *** transient behavior and the effects of various parameters of the salt pans,such as the depth of the brine layer,the absorptance of the soil surface,the thermal properties of the soil beneath the brine layer and the depth of the underground water table,on the evaporation process of salt pans are *** effects of extra insulation layer and the intensity of solar radiation are also examined.

关键词： salt pan solar radiation simulation

Relation between etching profile and voltage-current shape of sintered Sic etching by atmospheric pressure plasma

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Plasma Science and Technology 2019年第4期21卷 137-144页

作者： d c SEOK S R yOO K I LEE y S cHOI y H JUNG Plasma Technology Research center National Fusion Research InstituteGunsan City 54004Republic of Korea

Sintered silicon carbide(Sic)was etched by a dielectric barrier discharge source.A high voltage bipolar pulse was used with helium gas for the plasma *** stable filament plasma was generated and could be used for Sic *** the processing gas(NF3)mixing rate increased,the width and depth of the etching profile became narrower and *** differentiated V-Q Lissajous method was used for measuring the capacitances(ceq)of the electrode after the plasma turned *** width of the etching profile was proportional to *** the current peak value/smx of the substrate current in creased,the volume removal rate of Sic *** etch depth was proportional to the ratio of/smx to ***,because of the different characteristics of the plasma disks on Sic substrate by the voltage polarity,the etching profile was ***,in high NF3 mixing process,the etching profile became stable and deeper.

关键词： dielectric barrier discharge silicon carbide plasma etching、filament discharge,surface charge

Exercise preconditioning alleviates ischemia-induced memory deficits by increasing circulating adiponectin

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Neural Regeneration Research 2025年第5期20卷 1445-1454页

作者： Meifeng Zheng Borui Zhang Sonata S y yau Kwok-Fai So Li Zhang Haining Ou department of Rehabilitation Medicine Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina department of Rehabilitation Medicine The Fifth Clinical College of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Key Laboratory of cNS Regeneration(Ministry of Education) Guangdong-Hong Kong-Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina department of Rehabilitation Sciences The Hong Kong Polytechnic UniversityHong Kong Special Administrative RegionChina State Key Laboratory of Brain and cognitive Science Li Ka Shing Faculty of MedicineThe University of Hong KongHong Kong Special Administrative RegionChina center for Exercise and Brain Science School of PsychologyShanghai University of SportShanghaiChina Neuroscience and Neurorehabilitation Institute University of Health and Rehabilitation SciencesQingdaoShandong ProvinceChina

cerebral ischemia is a major health risk that requires preventive approaches in addition to drug *** exercise enhances neurogenesis and synaptogenesis,and has been widely used for functional rehabilitation after *** this study,we determined whether exercise training before disease onset can alleviate the severity of cerebral *** also examined the role of exercise-induced circulating factors in these *** mice were subjected to 14 days of treadmill exercise training before surgery for middle cerebral artery *** found that this exercise pre-conditioning strategy effectively attenuated brain infarct area,inhibited gliogenesis,protected synaptic proteins,and improved novel object and spatial memory *** analysis showed that circulating adiponectin plays a critical role in these preventive effects of *** activation of adiponectin receptors by Adipo Ron mimicked the effects of exercise,while inhibiting receptor activation abolished the exercise *** summary,our results suggest a crucial role of circulating adiponectin in the effects of exercise pre-conditioning in protecting against cerebral ischemia and supporting the health benefits of exercise.

关键词： adiponectin cerebral ischemia exercise pre-conditioning hippocampus memory function middle cerebral artery occlusion prefrontal cortex synaptic proteins treadmill exercise