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KALMAN FILTERING CORRECTION IN REAL-TIME FORECASTING WITH HYDRODYNAMIC MODEL

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Journal of Hydrodynamics 2008年第3期20卷 391-397页

作者： WU xiao-ling WANG Chuan-hai chen Xi XIANG xiao-hua ZHOU Quan State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing210098 China Shanghai pudong area hydrology bureau Shanghai 201208 China

Accurate and reliable flood forecast is crucial for efficient real-time river management, including flood control, flood warning, reservoir operation and river regulation. In order to improve the estimate of the initial state of the forecasting system and to reduce the errors in the forecast period a data assimilation procedure was often need. The Kalman filter was proven to be an efficient method to adjust real-time flood series and improve the initial conditions before the forecast. A new model integrating the hydraulic model with the Kalman filter for real-time correction of flood forecast was developed and applied in the Three Gorges interzone of the Yangtze River. The method was calibrated and verified against the observed flood stage and discharge during Three Gorges Dam construction periods （2004）. The results demonstrate that the new model incorporates an accurate and fast updating technique can improve the reliability of the flood forecast.

关键词： real-time flood forecast Kalman filter hydraulic model alternate Kalman filtering method

Mechanism and prediction of failure of diamond films deposited on various substrates by HFCVD

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中国有色金属学会会刊：英文版 2004年第z1期14卷 229-233页

作者： ZHOU Ling-ping SUN Xin-yuan LI Shao-lu LI De-yi chen xiao-hua College of Material Science and Engineering Hunan University Changsha 410082 China College of Material Science and Engineering Hunan University Changsha 410082 China College of Material Science and Engineering Hunan University Changsha 410082 China College of Material Science and Engineering Hunan University Changsha 410082 China College of Material Science and Engineering Hunan University Changsha 410082 China

Diamond films were deposited on the WC-Co cemented carbide and Si3N4 ceramic cutting tool substrates by hot-filament-assisted chemical vapour deposition. The adherence property of diamond films was estimated using the critical load (Pcr) in the indentation test. The adhesive strength of diamond films is related to the intermediate layer between the film and the substrate. Poor adhesion of diamond films to polished cemented carbide substrate is owing to the formation of graphite phase in the interface. The adhesion of diamond films deposited on acid etched cemented carbide substrate is improved, and the peeling-off of the films often happens in the loosen layer of WC particles where the cobalt element is nearly removed. The diamond films' adhesion to cemented carbide substrate whose surface layer is decarbonizated is strengthened dramatically because WC phase forms by reaction between the deposited carbon and tungsten in the surface layer of substrates during the deposition of diamond, which results in chemical combination in the film-substrate interface. The adhesion of diamond films to silicon nitride substrate is the firmest due to the formation of chemical combination of the SiC intermediate layer in the interfaces. In the piston-turning application, the diamond-coated Si3N4 ceramic and the cemented carbide cutting tools usually fail in the form of collapsing of edge and cracking or flaking respectively. They have no built-up edge(BUE) as long as coating is *** it wears through, BUE develops and the cutting force on it increases 1 - 3 times than that prior to failure. This can predict the failure of diamond-coated cutting tools.

关键词： diamond film cutting tool adhesion failure prediction cemented carbide

HYDROLYTIC CLEAVAGE OF ACMET-GLY PROMOTED BY CIS-[Pd（MET）（D₂O）₂]（NO₃）₂

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Chinese Chemical Letters 1996年第2期7卷 127-128页

作者： chen, xiao hua Zhu, Long Gen Kostić, N.M. Coordination Chemistry Institute State Key Lab of Coord. Chemistry Nanjing University Nanjing 210093 China Department of Chemistry Iowa State University Ames IA 50011 United States

cis-[Pd(met)(D2O)2]2+ promoted hydrolysis of AcMet-Gly was monitored by H NMR spectroscopy. The observed rate constants, Kobs, strongly depend on the mole ratio of cis-[Pd(met)(D2O)2]2+ to *** least,one aqua ligand for each Pd(II)is necessary for fast hydrolysis reaction observed. Two aqua ligands of each Pd(II) make the reaction faster.

关键词：埃阿

Heat treatment and granule medium internal highpressure forming of AA6061 tube

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Journal of Central South University 2017年第5期24卷 1040-1049页

作者： BI Jiang ZHAO Chang-cai BI Meng-meng DU Bing chen xiao-hua DONG Guo-jiang Key Laboratory of Advanced Forging&Stamping Technology and Science of Ministry of Education of China Yanshan UniversityQinhuangdao 066004China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China College of Vehicles and Energy Yanshan UniversityQinhuangdao 066004China

The new forming process of AA6061 alloy tube, including solution treatment, granule medium internal high-pressure forming and aging treatment, was developed. The AA6061 alloy tube via heat treatment satisfied the forming requirement, and the granule medium internal high pressure forming method for AA6061 alloy tube was also realized by using convenient implementation with low requirement of equipment and flexible design of product. At a solution temperature of 560℃ and time of 120 min, the elongation of the AA6061 extruded tube increases by 300% and the strength and the hardness dramatically decrease too. Therefore, the AA6061 alloy tube meets the requirement of internal high-pressure forming because of the improvement of formability. The experiments shows that the strength and hardness of AA6061 alloy workpiece recover to that of the as-received alloy at an aging temperature of 180℃ and time of 360 min, and the strength of AA6061 alloy workpiece is equal to the base alloy. The typical parts of convex ring tube, stepped shaft tube and hexagonal tube were successfully produced in lab by using the present forming method. The forming tests show that the maximum expansion ratio(MER) of the AA6061 extruded tube increases by 25.5% and the material properties of formed AA6061 alloy tube reached the performance of as-received alloy.

关键词： aluminum alloy tube solution treatment aging treatment granule medium internal high pressure forming

Effect of low curing temperature on the anticorrosion performance of composite coatings reinforced with modified Fe_(3)O_(4)

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Journal of Central South University 2024年第10期31卷 3435-3446页

作者： chen xiao-hua SUN Yi-xiang MAN cheng CUI Hong-zhi School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China

In this manuscript,the neat epoxy(EP)and functionalized Fe_(3)O_(4)(G-Fe_(3)O_(4))reinforced epoxy(G-Fe_(3)O_(4)/EP)coatings were cured under different temperatures,and the effect of the low curing temperature on the anticorrosion performance was *** experimental results show that the epoxy-amine ring-open addition reaction mainly exists in the curing process,and the activation energies of the reaction for the two coatings are 55.84 and 53.29 kJ/mol,*** the coatings cured at the low temperature,almost no pores could be detected on the fracture surface,but the presentence of the rough regions reflects the poor curing *** compared with the samples cured at the high temperature,the anticorrosion performance of the coatings with the low curing temperature is worse,and the decrease rate of the anticorrosion performance is slower,because of the poor curing state and low adhesion obtained at the low temperature.

关键词： low-temperature curing epoxy coating curing kinetics anticorrosion performance

Analysis of causes of pain after kyphoplasty for osteoporotic vertebral compression fractures

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Chinese Medical Journal 2013年第11期126卷 2192-2194页

作者： chen xiao-ming MA hua-song WANG Meng YANG Bin YUAN Wei Department of Orthopaedics the People's Liberation Army 306Hospital Beijing 100101 China

For the treatment of osteoporotic vertebral compression fractures （OVCFs）, percutaneous kyphoplasty （PKP）enables rapid pain relief and spinal stabilization, as well as correction of kyphosis. Although serious complications such as pulmonary embolism and spinal cord and nerve damage may occur,1 recurrence of pain after PKP is unlikely to require medical attention. The present study analyzed the causes of post-operative residual pain by reviewing the clinical data of 16 from 121 patients with OVCFs who underwent PKP from August 2005 to April 2009. METHODS

关键词： osteoporosis compression fractures kyphoplasty

S100A4 siRNA Inhibits Human Pancreatic Cancer Cell Invasion In Vitro

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Biomedical and Environmental Sciences 2012年第4期25卷 465-470页

作者： LI Na SONG Mao Min chen xiao hua LIU Li Hui LI Feng Sheng Department of General Surgery Beijing Tiantan Hospital Capital Medical University Beijing 100050 China Academy of Military Medical Sciences Beijing 100850 China

Objective Pancreatic cancer is one of the most deadly cancers, which is characterized by its high metastatic potential. S100A4 is a major prometastatic protein involved in tumor invasion and metastasis which precise role in pancreatic cancer has not been fully investigated. We knocked down the S100A4 gene in the Bxpc-3 pancreatic cancer cell line via RNA interference to study the changes in cell behavior. Methods Real-time polymerase chain reaction and western blotting were used to detect mRNA and protein expression levels of S100A4, matrix metalloproteinase （MMP）-2, E-cadherin and thrombospondin （TSP）-I. Transwell chambers were used to detect the migration and invasion abilities; a cell adhesion assay was used to detect adhesion ability; colony forming efficiency was used to detect cell proliferation; flow cytometry was used to detect apoptosis. Results S100A4 mRNA expression was reduced to 17% after transfection with SIOOA4-siRNA, and protein expression had a similar trend, mRNA and protein expression of MMP-2 was reduced and that of E-cadherin and TSP-1 was elevated, indicating that S100A4 affects their expression. S100A4-silenced cells exhibited a marked decrease in migration and invasiveness and increased adhesion, whereas overall proliferation and apoptosis were not overtly altered. Conclusion S100A4 and its downstream factors play important roles in pancreatic cancer invasion, and silencing AIOOA4 can significantly contain the invasiveness of pancreatic cancer.

关键词： Pancreatic cancer S100A4 Matrix metalloproteinase-2 E-cadherin Thrombospondin-1 RNA interference

Reinvestigation on the Reaction of Salicylic Chloride with Salicylic Amide and X-ray Crystal Structure of a New Macrocyclic Polyester

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Chinese Journal of Structural Chemistry 2003年第5期22卷 512-516页

作者： DU Da-Ming② chen xiao hua Wen-Ting JIN Xiang-Lin (Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China) Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University

The reaction of salicylic chloride and salicylic amide at 170 ℃ gave benzoxazine and a new macrocyclic polyester 3, whose crystal structure has been determined by single-crystal X-ray diffraction analysis. Compound 3: C28H16O8, Mr = 480.41, monoclinic, space group P21/n, a = 15.353(3), b = 14.196(3), c = 21.147(4) ? b = 103.32(3), V = 4485(2) ?, Z = 8, F(000) = 1984, Dc = 1.423 g/cm3 and m = 0.106 mm-1. The final R = 0.0535 and wR = 0.1275 for 7903 observed reflections (I ≥ 2(I)). In the asymmetric unit of the compound there exist two independent molecules which are connected by weak aromatic CH…O hydrogen bonding between C(47)?H(47) and atom O(7) of the carbonyl group.

关键词： salicylic chloride salicylic amide polyester macrocycle crystal structure

Distinct Rab7-related Endosomal-Autophagic-Lysosomal Dysregulation Observed in Cortex and Hippocampus in APPswe/PSEN1dE9 Mouse Model of Alzheimer＇s Disease

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Chinese Medical Journal 2017年第24期130卷 2941-2950页

作者： Li Ba xiao-hua chen Yan-Lin chen Qing Nie Zhi-Jun Li Feng-Fei Ding Min Zhang Department of Neurology Tongji Hospital of Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei 430030 China Department of Neurology Huangshi Central Hospital Huangshi Hubei 435000 China Department of Neurology Wuhan Central Hospital Wuhan Hubei 430014 China

Background：Amyloid-β deposition and accumulation of autophagic vacuoles are pathologic features of Alzheimer＇s disease （AD）.Dysregulation of the endosomal-autophagic-lysosomal （EAL） pathway,which impairs amyloid precursor protein processing,is one of the earliest changes in ***,the precise role of EAL pathway in neurodegeneration remains *** study aimed to investigate the role of EAL pathway in AD and further study the mechanism of EAL ***：We used 3-,7-,and 12-month-old APPswe/PSEN1dE9 （APP/PS1） mice to model different stages of AD with age-and gender-matched wild-type littermates as controls （4-7 mice per group） and detected the changes of EAL markers,endosomal organizers Rab5 and Rab7,autophagosome marker LC3B,and lysosomal proteins Lamp 1/2 in cortex and hippocampus by immunohistochemistry and Western blotting *** further explore the mechanism of EAL dysregulation in AD,components of the class Ⅲ phosphatidylinositol 3-kinase （PI3KC3） complex,activators ofRab7 （Beclin1 and UVRAG）,and the negative regulator of Rab7 （Rubicon） were also measured in this two brain ***：In 7-month-old APP/PS1 brain that amyloid beta initiated to accumulate intracellularly,EAL pathway,and related PI3KC3 members,UVRAG and Beclin1 were upregulated both in cortex and hippocampus （all P 〈 0.05）.By the age of 12 months old,when abundant amyloid plaques formed,EAL markers,UVRAG,and Beclin 1 were also upregulated in the cortex （all P 〈 0.05）.However,Rab7 was decreased significantly （P =0.0447）,accompanied by a reduction of its activating PI3KC complex component Beclin1 （P =0.0215） and enhancement of its inhibiting component Rubicon （P =0.0055） in the ***：Our study implies that EAL pathway,represented as Rab7 and its PI3KC3 regulators＇ expressions,showed temporal and spatial variation in brains at different stages of *** provides new insights into the role of EAL pathway in pathogenesis and indicates potential therapeutic

关键词： Autophagy Class III Phosphatidylinositol 3-Kinase Complex Endocytosis Neurodegeneration Rab7