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Wavy properties and analytical modeling of free-surface flows in the development of the multi-domain method

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Journal of Hydrodynamics 2016年第6期28卷 971-976页

作者： Xiaobo CHEN hui liang Deepwater Technology Research Centre Bureau Veritas

The wavy （oscillatory both in space and in time） properties of free-surface flows due to presence of floating bodies are analyzed within the framework of the potential-flow theory by assuming that the fluid is perfect and flow irrotational. A so-called new multi-domain method has been developed based on the fluid domain division by an analytical control surface surrounding bodies and the application of different methods adapted in the external and internal domains. In the analytical domain external to the control surface, the fundamental solution satisfying the linear boundary condition on the free surface associated with a point singularity （often called Green fimction and referred here as point solution） is applied to capture all wavy features of free-surface flows extending horizontally to infinity. Unlike classical studies in which the control surface is discretized, the unknown velocity potential and its normal derivatives are expressed by expansions of orthogonal elementary functions. The velocity potential associa- ted with each elementary distribution （elementary solutions） on the control surface can be obtained by performing multi-fold inte- grals in an analytical way. In the domain internal to the control surface containing the bodies, we could apply different methods like the Rankine source method based on the boundary integral equations for which the elementary solutions obtained in the external domain playing the role of Dirichlet-to-Neumarm operator close the problem.

关键词： analytical modeling multi-domain method point solution (PS) elementary solution (ES) body solution (BS)

Microstructure and improved mechanical properties of Mo-12Si-8.5B alloys with lanthanum oxide addition

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Rare Metals 2019年第9期38卷 848-854页

作者： Xiao-hui Lin Bin Li Lai-Ping Li Jing liang Xuan-Qiao gao Xin Zhang Refractory Metals Material Research Center Northwest Institute for Non-ferrous Metal Research

Mo-12 Si-8.5 B alloys with different La2 O3 contents were fabricated by mechanical alloying and then hot *** effects of La2 O3 on microstructure,room and elevated temperature mechanical properties of Mo-12 Si-8.5 B alloys were *** microstructure of Mo-12 Si-8.5 B alloy with La2 O3 additions exhibits a continuous α-Mo matrix,where the spherical Mo3 Si and Mo5 SiB2 intermetallic phases are distributed inside the grains and along the grain *** detailed microstructure shows that some nanoscale La2 O3 particles are dispersed mainly in the a-Mo grains and partially in the *** La2 O3 particles can refine the grain sizes of a-Mo matrix and intermetallic,but the refining effect is limited with the La2 O3 addition further *** mechanical testing results show that the La2 O3 addition simultaneously improves the compression strength and fracture toughness of Mo-12 Si-8.5 B alloy,due to that theα-Mo matrix is strengthened and toughened at ambient temperature and intermetallics are strengthened at elevated *** enhancing effect is sensitive to the amount of La2 O3 additions,and the Mo-12 Si-8.5 B alloy can obtain a better combination of strength and toughness when the content of La2 O3 is 0.9 wt%.

关键词： Composite materials Mo silicide Nanoparticles Microstructure Compression property Fracture toughness

Performance of Three Adelphocoris spp.(Hemiptera: Miridae) on Flowering and Non-flowering Cotton and Alfalfa

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Journal of Integrative Agriculture 2014年第8期13卷 1727-1735页

作者： gao Zhen PAN Hong-sheng LIU Bing LU Yan-hui liang Ge-mei State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences

The genus Adelphocoris（Hemiptera： Miridae） is a group of key insect pests in cotton fields in China that includes three dominant species： A. suturalis（Jakovlev）, A. lineolatus（Goeze） and A. fasciaticollis（Reuter）. Previous field surveys have found that adults of these Adelphocoris species usually move onto specific host plants when the plants enter the flowering stage. To determine the potential trade-offs for this host-plant preference behavior, the performance of these three Adelphocoris spp. on flowering and non-flowering cotton and alfalfa were compared in the laboratory. The results showed that Adelphocoris spp. had significantly higher nymphal developmental and survival rates, along with increased adult longevity and fecundity on flowering cotton and alfalfa than on non-flowering plants of either species. In addition, compared with cotton plants, alfalfa generally promoted better performance of these three Adelphocoris species, especially for A. lineolatus. Simple correlation analysis indicated that female adult longevity was positively correlated to male adult longevity and female fecundity, and female fecundity was positively correlated to nymphal development and survival rates. This study demonstrated a positive correlation between adult preference and offspring/adult performance for all three Adelphocoris species, with no evidence of any trade-offs for this preference for flowering host plants. These findings support the hypothesis that hemimetabolous insects such as mirid bugs have positive adult preference-adult/nymphal performance relationships, which is likely due to the similar feeding habits and nutritional requirements of adults and nymphs.

关键词： Adelphocoris lineolatus Adelphocoris suturalis Adelphocoris fasciaticollis preference-performance relationship cotton alfalfa flowering stage

Kidney inflammatory myofibroblastic tumor masquerading as metastatic malignancy: A case report and literature review

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World Journal of Clinical Cases 2019年第24期7卷 4366-4376页

作者： Guo-hui Zhang Xiao-Yan Guo gao-Zhao liang Qing Wang Graduate School Guangdong Medical UniversityZhanjiang 524000Guangdong ProvinceChina Department of Urology The Second Affiliated HospitalShenzhen UniversityShenzhen 518100Guangdong ProvinceChina

BACKGROUND Inflammatory myofibroblastic tumor(IMT) is a rare mesenchymal tumor that is characterized by spindle cells differentiated from muscle fibroblasts and infiltration of various types of inflammatory cells. IMT can occur at any age and at any anatomic site. The most common location of IMT is the bladder in the genitourinary tract. Only scarce cases of kidney IMT have been reported in the *** SUMMARY A 77-year-old woman, with a history of bilateral renal calculus for 15 years, was admitted to the Department of Urology of our hospital complaining of recurrent painless gross hematuria for one month. The treatment with cephalosporin was ineffective. Computed tomography imaging showed a mixed density and slightly heterogeneously enhanced lesion in the middle pole of the left kidney and ipsilateral adrenal enlargement. The patient underwent surgical treatment by retroperitoneoscopic left radical nephrectomy plus adrenalectomy. A large number of typical spindle cells surrounded by plasma cells and lymphocytes were observed microscopically. Immunohistochemical analyses indicated that these spindle cells were positive for vimentin, cytokeratin(CK), Ki-67, CK7,CD34, and CD31 and were focally positive for CD10 and anaplastic lymphoma kinase(ALK-1). Thus, a diagnosis of IMT was made definitively. The patient recovered well after operation, and no recurrence or metastasis was noted during the 22-mo *** Since kidney IMT is very rare and lacks characteristic clinical manifestation, it is easily misdiagnosed as a malignant tumor before operation. Surgery remains the best choice for diagnosis and treatment, and such cases must be followed carefully because of the uncertain biological behavior of this tumor. This report suggests that renal calculus may be one of the causes of IMT, but further investigation is necessary to prove it.

关键词： Inflammatory myofibroblastic tumor Kidney Diagnosis Renal calculus Case report

Recrystallization texture development in rare-earth(RE)-doped non-oriented silicon steel

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Journal of Iron and Steel Research International 2020年第11期27卷 1339-1346页

作者： Zheng-hua He Yu-hui Sha Yong-kuang gao Song-tao Chang Fang Zha liang Zuo Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Northeastern UniversityShenyang 110819Liaoning.China

High-grade non-oriented silicon steel with higher permeability and lower core loss has become the pursed target with the rapid developnient of electrical *** effects of rare-earth(RE)element on recrystallization texture in RE-doped Fe-3.1 wt.%Si-1.2 wt.%Al non-oriented silicon steel were investigated by macro-and micro-texture *** variation of recrystallization texture with RE element content was *** the competition among main recrystallization texture components,favorable{113}and X fiber(//ND)are strengthened and unfavorable y fiber is evidently decreased by the addition of RE element,whereas the effect of RE element is reversed by excess RE *** recrystallization texture development is determined by RE-affected nucleation and grain growth in terms of grain boundary migration related to segregation and *** properly inhibited grain boundary mobility can promote favorable recrystallization texture by the improved nucleation and efficient grain growth.

关键词： Non-oriented silicon steel Texture Rare-earth element Grain boundary Segregation

A Comprehensive Review of Isogeometric Topology Optimization:Methods,Applications and Prospects

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Chinese Journal of Mechanical Engineering 2020年第6期33卷 24-37页

作者： Jie gao Mi Xiao Yan Zhang liang gao Department of Engineering Mechanics School of Aerospace EngineeringHuazhong University of Science and TechnologyWuhan430074China Hubei Key Laboratory for Engineering Structural Analysis and Safety Assessment Huazhong University of Science and TechnologyWuhan430074China The State Key Lab of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China School of Machinery and Automation Wuhan University of Science and TechnologyWuhan430081China

Topology Optimization(TO)is a powerful numerical technique to determine the optimal material layout in a design domain,which has accepted considerable developments in recent *** classic Finite Element Method(FEM)is applied to compute the unknown structural responses in ***,several numerical deficiencies of the FEM significantly influence the effectiveness and efficiency of *** order to eliminate the negative influence of the FEM on TO,IsoGeometric Analysis(IGA)has become a promising alternative due to its unique feature that the Computer-Aided Design(CAD)model and Computer-Aided Engineering(CAE)model can be unified into a same mathematical *** the paper,the main intention is to provide a comprehensive overview for the developments of Isogeometric Topology Optimization(ITO)in methods and ***,some prospects for the developments of ITO in the future are also presented.

关键词： Topology optimization Isogeometric analysis CAD CAE

Studies on Rheological, Thermal, and Mechanical Properties of Polylactide/Methyl Methacrylate-Butadiene-Styrene Copolymer/Poly(propylene carbonate) Polyurethane Ternary Blends

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Chinese Journal of Polymer Science 2019年第12期37卷 1273-1282,I0007页

作者： Ji-Li Zhao Hong-Wei Pan hui-Li Yang Jun-Jia Bian hui-liang Zhang Ge gao Li-Song Dong College of Chemistry Jilin UniversityChangchun 130012China Department of Science Beihua UniversityJilin 132013China Key Laboratory of Polymer Ecomaterials Chinese Academy of SciencesChangchun Institute of Applied ChemistryChangchun 130022China Zhejiang Zhongke Applied Chemistry Technology Co. Ltd.Hangzhou 310000China

Polylactide(PLA),methyl methacrylate-butadiene-styrene copolymer(MBS),and poly(propylene carbonate)polyurethane(PPCU)were blended and subjected to blown film *** rheological,mechanical,morphological,thermal,and crystalline properties of the PLA/MBS/PPCU ternary blends and the mechanical properties of the resulting films were *** of mechanical test showed that PPCU and MBS could synergistically toughen *** impact strength of 50/10/40 PLA/MBS/PPCU blend(74.7 k J/m^2)was about 7.5 times higher than that of the neat PLA(10.8 k J/m^2),and the elongation at break of 50/10/40 PLA/MBS/PPCU blend(276.5%)was higher by about 45 times that of PLA(6.2%).The tear strength of PLA/MBS/PPCU films was 20 k N/m higher than that of PLA,and the elongation at break(MD/TD)of 50/10/40 PLA/MBS/PPCU films was 271.1%/222.3%,whereas that of PLA was only 2.7%/3.0%.POM observations displayed that the density of spherulite nucleation increased and the size of crystalline particles decreased with the addition of *** increasing PPCU content from 5%to 20%,the density of spherulite nucleation increased and the size of crystalline particles decreased continuously,but the nucleation density of spherulites was slightly lowered with increasing PPCU content from 30%to 40%.The PLA/MBS/PPCU films exhibited excellent mechanical properties,which expanded the application range of these biodegradable films.

关键词： Biodegradable Polylactide Poly(propylene carbonate)polyurethane Methyl methacrylate-butadiene-styrene copolymer Films

Effects of heat treatment on the corrosion resistance of carbon steel coated with LaMgAl_(11)O_(19) thermal barrier coatings

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International Journal of Minerals,Metallurgy and Materials 2015年第10期22卷 1050-1059页

作者： liang-liang Huang hui-min Meng Li-kang liang Sen Li Jin-hui Shi Institute for Advanced Materials and Technology University of Science and Technology Beijing

LaMgAl11O19thermal barrier coatings（TBCs） were applied to carbon steels with a NiCoCrAlY bond coat by plasma spraying. The effects of heat treatment on the corrosion resistance of carbon steel coated with LaMgAl11O19TBCs were investigated in 3.5wt% Na Cl solution using polarization curves, electrochemical impedance spectroscopy（EIS）, scanning electron microscopy（SEM）, and X-ray diffraction（XRD）. The results show that a large number of cracks are found in the LaMgAl11O19TBCs after the samples are heat-treated, including some through-thickness cracks. The corrosion forms of the as-sprayed and heat-treated TBCs are uniform corrosion and pitting corrosion, respectively. The as-sprayed TBCs exhibit three EIS time constants after being immersed for less than 7 d, and then a new time constant appears because of steel substrate corrosion. When the immersion time is increased to 56 d, a Warburg impedance（W） component appears in the EIS data. The EIS data for the heat-treated TBCs exhibit only two time constants after the samples are immersed for less than 14 d, and a new time constant appears when the immersion time is increased further. The heat treatment reduces the corrosion resistance of carbon steel coated with LaMgAl11O19TBCs. The corrosion products are primarily γ-Fe OOH and Fe3O4.

关键词： thermal barrier coatings carbon steel corrosion pl

The Record-Breaking Extreme Drought in Yunnan Province, Southwest China during Spring-Early Summer of 2019 and Possible Causes

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Journal of Meteorological Research 2020年第5期34卷 997-1012页

作者： Ting DING hui gao National Climate Center China Meteorological AdministrationBeijing 100081

In spring and early summer of 2019, Yunnan Province experienced the most severe seasonal drought on record,with days of extreme drought area exceeding 10^5 km^2 far more than normal. Consistently, the precipitation in each month from February to June is over 30% less than normal, and about 50% less in the most severe drought period(April–June). The rainy season in Southwest China(SWC) started on the third pentad in June 2019, which is the second latest in history. The rainy season in Yunnan started on 24 June, which is the latest(29 days later than normal). On the contrary, the onset of the South China Sea summer monsoon(SCSSM) is abnormally early. The lag time between the start of the rainy season in SWC and the onset of the SCSSM in 2019 is 7 pentads, which is the largest since 1961, much longer than the climate mean(less than 1 pentad). The present study analyzes the possible reasons why the rainy season came extremely late and the drought disaster persisted and intensified after a much early SCSSM, at both seasonal and subseasonal timescales. The abnormally late onset of the rainy season and the second greatest potential evapotranspiration(PET) since 1981 are the direct reasons for the persistent drought. Statistical results show that the water vapor from southwest of Yunnan in April–June contributes more than that from the east at the seasonal scale. In April–June 2019, however, the southern branch trough(SBT) was abnormally weak, the large and strong anticyclonic wind anomaly prevailed over the Bay of the Bengal(BOB), and the meridional water vapor transport to Yunnan was weak. At the subseasonal scale, the weaker SBT lasted the longest, and the strong convection over the BOB came up late despite of an early onset of the SCSSM, which resulted in reduced low-level moisture convergence in Yunnan and development of drought prior to the SCSSM onset. From the onset of SCSSM to the start of rainy season in SWC, the SBT and meridional water vapor transport from the B

关键词： Yunnan Province extreme drought South China Sea summer monsoon(SCSSM) rainy season in Southwest China(SWC) southern branch trough(SBT)