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LOW-FREQUENCY CIRCULATION AND EXTENDED-RANGE FORECAST IN CONNECTION WITH AUTUMN EXTREME HEAVY RAINFALL PROCESS IN HAINAN

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Journal of Tropical Meteorology 2019年第4期25卷 542-552页

作者： WEI Xiao-wen LIANG Ping wu hui Hainan Meteorological Services Center Haikou 570203 China Key Laboratory of Southern China Sea Meteorological Disaster Prevention and Mitigation of Hainan Province Haikou 570203 China Shanghai Climate Center Shanghai 200030 China Hainan Climate Center Haikou 570203 China

Observed daily precipitation data from the National Meteorological Observatory in Hainan province and daily data from the National Centers for Environmental Prediction/National Center for Atmospheric Research(NCEP/NCAR)reanalysis-2 dataset from 1981 to 2014 are used to analyze the relationship between Hainan extreme heavy rainfall processes in autumn(referred to as EHRPs) and 10-30 d low-frequency circulation. Based on the key low-frequency signals and the NCEP Climate Forecast System Version 2(CFSv2) model forecasting products, a dynamical-statistical method is established for the extended-range forecast of EHRPs. The results suggest that EHRPs have a close relationship with the 10-30 d low-frequency oscillation of 850 hPa zonal wind over Hainan Island and to its north, and that they basically occur during the trough phase of the low-frequency oscillation of zonal wind. The latitudinal propagation of the low-frequency wave train in the middle-high latitudes and the meridional propagation of the low-frequency wave train along the coast of East Asia contribute to the"north high(cold), south low(warm)"pattern near Hainan Island, which results in the zonal wind over Hainan Island and to its north reaching its trough,consequently leading to EHRPs. With the link between low-frequency circulation and EHRPs being considered, a low-frequency wave train index(LWTI) is defined and adopted to forecast EHRPs by using NCEP CFSv2 forecasting products. EHRPs are predicted to occur during peak phases of LWTI with value larger than 1 for three or more consecutive forecast days. Hindcast experiments for EHRPs in 2015-2016 indicate that EHRPs can be predicted 8-24 d in advance, with an average period of validity of 16.7 d.

关键词： heavy rainfall process extended-range forecast method low-frequency oscillation 10-30d CFSv2

Monomeric and self-assembled crystal phases of TNBT

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Rare Metals 2024年第10期43卷 5442-5448页

作者： Yun-hui wu Hua-Bei You Wei-Kai Cui Zhi-Qian Cao Xiao Dong Zi-hui Meng Ming Huang School of Chemistry and Chemical Engineering Beijing Institute of TechnologyBeijing 100081China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China

(3,3′,5,5′-Tetranitro-4,4′-bi-1,2,4-Triazole)TNBT was designed and predicted more than three decades ago as a high energy *** with many other designed molecules,TNBT has not been successfully synthesized and has not been computationally studied in *** this work,theoretical calculations at density functional theory(DFT)level of theory were carried out for both the gas phase molecule and its possible bulk crystal phases.

关键词： material crystal theory

Micro RNAs in cancer therapeutic response: Friend and foe

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World Journal of Clinical Oncology 2014年第4期5卷 730-743页

作者： Jingyan Xue Jixiao Niu Jiong wu Zhao-hui wu Department of Breast Surgery Fudan University Shanghai Cancer Center Department of Oncology Shanghai Medical College Fudan University Center for Cancer Research University of Tennessee Health Science Center Memphis TN 38163 United States Department of Pathology and Laboratory Medicine University of Tennessee Health Science Center Memphis TN 38163 United States

Cancer initiation and development engage extremely complicated pathological processes which involve alterations of a large number of cell signaling cascades and functional networks in temporal and spatial orders. During last decades, microR NAs(miR NAs), a class of noncoding RNAs, have emerged as critical players in cancer pathogenesis and progression by modulating many pathological aspects related to tumor development, growth, metastasis, and drug resistance. The major function of miR NAs is to post-transcriptionally regulate gene expression depending on recognition of complementary sequence residing in target mR NAs. Commonly, a particular mi RNA recognition sequence could be found in a number of genes, which allows a single miR-NA to regulate multiple functionally connected genes simultaneously and/or chronologically. Furthermore, a single gene can be targeted and regulated by multiple miR NAs. However, previous studies have demonstrated that mi RNA functions are highly context-dependent,which leads to distinct pathological outcomes in different types of cancer as well as at different stages by alteration of the same miR NA. Here we summarize recent progress in studies on miR NA function in cancer initiation, metastasis and therapeutic response, focusing on breast cancer. The varying functions of mi RNAs and potential application of using miR NAs as biomarkers as well as therapeutic approaches are further discussed in the context of different cancers.

关键词： MicroRNA Breast cancer Therapeutic response Biomarker

Community Composition and Structure of Soil Macro-Arthropods Under Agricultural Land Uses in the Black Soil Region of Jilin Province, China

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Agricultural Sciences in China 2006年第6期5卷 451-455页

作者： wu Dong-hui ZHANG Bai CHEN Peng College of Earth Sciences Jilin University Changchun 130061 P.R.China Northeast Institute of Geography and Agricultural Ecology the Chinese Academy of Sciences （CAS） Changchun 130012 PR.China School of Urban and Environment Northeast Normal University Changchun 130024 P.R.China

Soil macro-arthropods in the black soil region in Jilin Province of China were investigated with the emphasis laid on the species richness and abundance in relation to the types of land-use, i.e., farm yard, farm land and Three-North Forest Shelter Belt. Soil macro-arthropods were hand-sorted in the field. A total of 2 357 soil macro-arthropod individuals was captured and fell into 70 families. The results suggested that type of land use affected the species richness and abundance of soil macro-arthropods. Agricultural practices had a strong impact on the soil macro-arthropods community, the conventional cultivations changed the vertical structure of macro-arthropods in the soil profile, and improved the richness and abundance of macro-arthropods in the lower soil layers especially in July. The results also showed that different groups of soil macro-arthropods had various responses to land use changes.

关键词： soil macro-arthropods black soil land use Jilin Province

Mechanical Property of M40J_f/5A06Al Composite at Elevated Temperatures

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Acta Metallurgica Sinica(English Letters) 2015年第9期28卷 1175-1182页

作者： Da-Guang Li Guo-Qin Chen Long-Tao Jiang Xiu Lin Gao-hui wu School of Materials Science and Engineering Harbin Institute of Technology State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology Heilongjiang Academy of Industrial Technology

In this work, aluminum alloy with a high concentration of magnesium （5A06） was reinforced with 55 vol% unidirectional ultra-high modulus and highly graphitized carbon fiber （M40J） using pressure infiltration method. The effect of temperature on the bending strength of the Cf/A1 composites was investigated from room temperature to 500 ℃. The experimental results showed that the strength of M40Jf/5A06A1 composites was not affected by temperature from room temperature to 200 ℃. The bending strength of the composite at 300 ℃ was decreased by 30% compared with that at room temperature. In order to evaluate the extent of interface weakening, the length of fiber pullout was measured. The results showed that the pullout length reached the maximum at 300 and 500 ℃, which indicated weak interface at the corre- sponding temperature. The DSC curve presented obvious heat absorption peak at around 300 ℃, which may be attributed to the dissolution of the interfacial product （A13Mg2） phases at the C/A1 interface. The bending fracture surfaces of the composites after three-point bending tests were observed by SEM, plastic-viscous flow of the matrix were observed at the samples tested at 500 ℃. The predominant mechanisms for high-temperature damage of M40Jf/5A06A1 composites are matrix softening caused by dislocation recovery and interface weakening caused by the dissolution of interfacial products.

关键词： Carbon fiber Aluminum Metal matrix composites High-temperature properties Fiberpullout length

A pixel-level local contrast measure for infrared small target detection

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Defence Technology（防务技术） 2022年第9期18卷 1589-1601页

作者： Zhao-bing Qiu Yong Ma Fan Fan Jun Huang Ming-hui wu Xiao-guang Mei School of Electronic Information and the School Aerospace Research Wuhan UniversityWuhan430074China

Infrared(IR) small target detection is one of the key technologies of infrared search and track(IRST)systems. Existing methods have some limitations in detection performance, especially when the target size is irregular or the background is complex. In this paper, we propose a pixel-level local contrast measure(PLLCM), which can subdivide small targets and backgrounds at pixel level *** pixel-level segmentation, the difference between the target and the background becomes more obvious, which helps to improve the detection performance. First, we design a multiscale sliding window to quickly extract candidate target pixels. Then, a local window based on random walker(RW) is designed for pixel-level target segmentation. After that, PLLCM incorporating probability weights and scale constraints is proposed to accurately measure local contrast and suppress various types of background interference. Finally, an adaptive threshold operation is applied to separate the target from the PLLCM enhanced map. Experimental results show that the proposed method has a higher detection rate and a lower false alarm rate than the baseline algorithms, while achieving a high speed.

关键词： Infrared(IR)small target Irregular size Random walker(RW) Pixel-level local contrast measure(PLLCM)

SYNTHESIS AND CRYSTAL STRUCTURE OF A NEW COMPOUND Sr_6Sn_2Nb_8O_30

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Journal of wuhan University of Technology(Materials Science) 1999年第2期14卷 35-39页

作者： FANG Liang ZHANG hui wu Bolin YUAN Runzhang wuhan University of Technology wuhan University of Technology China State Key Lab. Adv. Tech. Mater. S. Wuhan Univ. of Tech. Wuhan 430070 China

A new compound Sr6Sn2Nb8O30 was found in the ternary system of SrO-SnO2-Nb2O5. The transparent colorless crystal with needle-like shape can be grown by flux method. The crystal structure of new compound was determined by X-ray diffraction, and its belongs to tungsten bronze structure. Sr6Sn2Nb8O30 crystallizes in orthorhombic system with unit cell parameters a= 17. 579 (DA,6= 17. 509(DA,c=7. 7880(5)A,Z = 4 and space group Cmm2.

关键词： Sr_6Sn_2Nb_8O_30 system new compound tungsten bronze structure

Influences of Technological Parameters on Smelting-separation Process for Metallized Pellets of Vanadium-bearing Titanomagnetite Concentrates

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Journal of Iron and Steel Research International 2016年第7期23卷 655-660页

作者： En-hui wu Rong ZHU Shao-li YANG Lan MA Jun LI Jing HOU School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Innovation and Technology Center of Panxi Panzhihua University

The smelting-separation process for metallized pellets of vanadium-bearing titanomagnetite concentrates was *** influences of smelting temperature,smelting time,and the basicity of the metallized pellet on vanadium and iron recovery were *** characteristics of titanium slag were analyzed using X-ray diffraction,energy dispersive spectroscopy,and mineralographic microscopic *** results demonstrate that appropriate increases in smelting temperature and smelting time can improve the vanadium and iron recovery from metallized pellets and are beneficial for the slag-iron *** increasing the basicity of the metallized pellet can considerably improve the vanadium and iron recovery,the TiO;grade of titanium slag was *** the optimal conditions,90.17% of vanadium and 92.98% of iron in the metallized pellet were recovered,and the TiO;grade of titanium slag was 55.01%.It was found that anosovite,augite,spinel,glassiness,and metallic iron were the main mineral phases of the titanium slag.

关键词： metallized pellet smelting separation titanium slag vanadium vanadium-bearing titanomagnetite concentrate

Synthesis of Ruthenium Xanthate Complex and Its Electrocatalytic Activity for Tryptophan Oxidation

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Chemical Research in Chinese Universities 2013年第3期29卷 574-578页

作者： wu Fang-hui CHEN Le CHU Xiang-feng WEI Xian-wen School of Chemistry and Chemical Engineering Anhui University of Technology Maanshan 243002 P. R. China

A new ruthenium complex containing bidentate xanthate ligands was synthesized in a good yield. This complex was characterized by elemental analysis, proton nuclear magnetic resonance（tH NMR）, Fourier transform infrared（FTIR） and UV-Vis spectroscopies. The cyclic voltammetry of the complex revealed one quasi-redox wave centered at Ru（III）/Ru（II） couple, indicating its catalytic potential. So the preparation of a glass carbon electrode modified with ruthenium xanthate complex and its electrocatalytic activity toward the oxidation of tryptophan（Trp） were also studied. The experimental results show that the modified electrode had excellent electrocatalytic activity for the oxidation of tryptophan. Moreover, under the optimized conditions, the oxidation peak current was propor- tional to tryptophan concentration in a range of 2.5×10-7 to 5.0× 10-5 mol/L with a correlation coefficient of 0.9928 and a detection limit of 8.3 × 10-8 mol/L（S/N=3）. Using the proposed method, tryptophan was successfully determined in pharmaceutical samples with standard addition method.

关键词： Ruthenium xanthate complex Electrocatalytic activity Tryptophan