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A New Lie Algebra and a Way to Generate Multiple Integrable Couplings

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Communications in Theoretical Physics 2007年第12期48卷 979-982页

作者： FENG Bin-Lu~(1,2)and HAN Bo~1~1 department of mathematics,Harbin Institute of Technology,Harbin 150001,china~2 department of mathematics,Weifang university,Weifang 261000,china department of mathematics Harbin Institute of Technology department of mathematics Weifang University

A new higher-dimensional Lie algebra is constructed,which is used to generate multiple integrable *** this,we come to a general approach for seeking multi-integrable couplings of the known integrablesoliton equations.

关键词： Lie algebra integrable hierarchy Hamiltonian structure

APPLICATIONS　OF　ODE　METHOD

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南京大学学报(自然科学) 1996年第4期 135-137页

作者： Wu Xingyuan Ouyang Zixiang ( department of mathematics,Nanjing university,210093,Nanjing,PRC)

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关键词： ODE method system of linear eguations nonlinear eguation optimization

INFLUENCE OF ASSOCIATED AND SEPARATE PRECIPITATION OF γ″ AND γ′ ON STRUCTURE STABILITY IN INCONEL718 AND MODIFIED ALLOYS

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Acta Metallurgica Sinica(English Letters) 1993年第6期6卷 410-414页

作者： DONG jianxin XIE Xishan ZHANG Shouhua university of Science and Technology Beijing,Beijing,china doctorate student,department of Materials Science and Engineering,university of Science and Technology Beijing,Beijing 100083,china Univ of Science and Technology Beijing Beijing China

The precipitation behavior in Inconel 718 and modified alloys has been studied by means of *** structure of associated precipitation and compact morphology of γ″+γ′ were ob- tained by modifying the contents of Al,Ti and *** results show that the com- pact morphology of γ″+γ′ has the best structure stability at higher *** of the transformation γ″→δ in alloy 718 the dissolution of strengthening phases in modified alloy leads material degradation.

关键词： superalloy structure stability associated precipitation compact morphology Inconel 718

On the evolution and histology of some Cambrian protoconodonts, paraconodonts and primitive euconodonts

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Science china Earth Sciences 2004年第7期47卷 577-584页

作者： DONG Xiping department of Geology, Peking university, Beijing 100871, china Laboratory of Palaeobiology & Stratigraphy, Nanjing Institute of Ge-ology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, china 1. department of Geology Peking University 100871 Beijing China 2. Laboratory of Palaeobiology & Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences 210008 Nanjing China

Previous reports on the morphological evolution of protoconodonts and paraconodonts are reviewed. The evolutionary trends exhibited by species of the protoconodont genus Gapparodus and the paraconodont genus Westergaadodina are discussed. Based on the present study on histology, genus Paibiconus is protoconodont, while genus Yongshunella is paraconodont (fig. 1 (a)). However, the nature of Huayuanodontus has not been fully understood so far. Recently, the transitional form New Gen. Sensu Miller, 1980 of late Late Cambrian has been found in Hunan Province, South china. It is considered as the Sister-Group of Proconodontus. Moreover, another kind of transitional form of middle Late Cambrian and late Late Cambrian between Prooneotodus notundatus and Pnoconodontus, which looks like Prooneotodus notundatus in gross morphology, but has anterior and posterior costae, has also been found in Hunan, South china. This kind of transitional form is believed to be probably the real intermediate link between Prooneotodus rotundatus and Pnoconodontus, and Prooneotodus rotundatus is most probably the ancestor of Proconodontus. The two transitional forms noted above are all euconodonts by the study of their histology. Unlike the euconodonts of Post-Cambrian, the evolutionary relationships among the species of protoconodonts, paraconodonts and the primitive euconodonts could not be made clear without the histological study on them.

关键词： protoconodonts, paraconodonts, evolution, histology, Cambrian.

Characterization of Low Pressure RF Plasma Heating

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International Journal of Minerals,Metallurgy and Materials 1998年第1期12卷 31-35页

作者： Wenxia Pan Fanxiu Lu Toyonobu Yoshida (Materials Science and Engineering School, university of Science and Technology Beijing, Beijing 100083, china)(department of Metallurgy, The university of Tokyo, Tokyo 113, Japan) Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China department of Metallurgy University of Tokyo Tokyo 113 Japan

Compacts of a-Al2O3 and Mo powder were heated in radio-frequency (RF) induced low pressure N2, H2,Ar, and their mixture plasma. An optical pyrometer, a radiation pyrometer, and a system called Accufiber Model310 were used to measure the temperature of compacts heated in the plasma. The results indicate that there are different heat transfer mechanisms from plasma to specimens of different physical properties. The Ar plasma showed thehighest heating ability among N2, H2, and Ar plasma for Al2O3 specimens, whereas the H2 plasma could heat Mospecimens to a higher temperature than the Ar plasma did, even under the same generating conditions.

关键词： plasma heating temperature measurement heat transfer mechanism

基于统计能量分析法的轿车内室噪声优化与控制

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同济大学学报（自然科学版） 2002年第7期30卷 862-867页

作者：靳晓雄叶武平丁玉兰同济大学汽车工程系上海200092 上海上汽大众产品规划部上海200063 同济大学机械工程系上海200092

建立了一个统计能量分析 (SEA)模型用于轿车内室噪声的仿真计算 .40 0～ 5 0 0 0Hz频率范围内SEA模型的计算结果与车内声压水平实测值的误差达到 3dB以内 .基于此模型进行了轿车内室噪声的优化与控制研究 ,获得一系列有价值的分析结果 .

关键词：统计能量分析法轿车内室噪声噪声控制仿真计算车辆振动噪声

FINITE ELEMENT EXPANSION FOR VARIABLE COEFFICIENT ELLIPTIC PROBLEMS

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Systems Science and Mathematical Sciences 1989年第1期2卷 54-69页

作者：丁彦恒林群 department of mathematics Yunnan UniversityKunmingChina Institute of Systems Science Academia SinicaBeijingChina

The Ritz projections of the elliptic problem（?）(aij（?）ju)+c0u=f in Ω,u=0 on （?）Ω,and the quasilinear eiliptic problem（?）（ai（x,Du））+a0（x,Du）=0 in Ω,u=0 on （?）Ωwith linear finite elements admit an asymptotic error expansion,respectively,for certain classes of“uniform” *** provides the theoretical justification for the use of Richardson extrapolationfor increasing the accuracy of the scheme from O（h2） to O（h4 |ln h|）.

关键词： finites elements asymptotic error expansion variable coefficient elliptic operator quasilinear elliptic problem

Effects of melatonin on learning abilities, cholinergic fibers and nitric oxide synthase expression in rat cerebral cortex

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Neural Regeneration Research 2006年第8期1卷 677-680页

作者： Bin Xu1, Junpao Chen2, Hailing Zhao3 1department of Neurology, the 187 Hospital of Chinese PLA, Haikou 571159, Hainan Province, china 2department of Neurology, Zhujiang Hospital, Southern Medical university, Guangzhou 510282, Guangdong Province, china 3Outpatient department, Haikou Hospital of Traditional Chinese Medicine, Haikou 570003, Hainan Province, china department of Neurology The 187 Hospital of Chinese PLA Haikou 571159 Hainan Province China department of Neurology Zhujiang Hospital Southern Medical University Guangzhou 510282 Guandong Province China Outpatient department Haikou Hospital of Tradiational Chinese Medicine Haikou 570003 Hainan Province China

BACKGROUND: Melatonin is a kind of hormones derived from pineal gland. Recent researches demonstrate that melatonin is characterized by anti-oxidation, anti-senility and destroying free radicals. While, effect and pathogenesis of pineal gland on learning ability should be further studied. OBJECTIVE: To investigate the effects of pinealectomy on learning abiliy, distribution of cholinesterase and expression of neuronal nitric oxide synthase (nNOS) in cerebral cortex of rats and probe into the effect of melatonin on learning ability, central cholinergic system and nNOS expression. DESIGN: Randomized grouping design and animal study. SETTING: department of Neurology, the 187 Hospital of Chinese PLA. MATERIALS: A total of 12 male SD rats, of normal learning ability testing with Y-tape maze, of clean grade, weighing 190-210 g, aged 6 weeks, were selected in this study. METHODS: The experiment was carried out in the department of Neurology, Zhujiang Hospital from July 1997 to June 2000. All SD rats were divided into experimental group (n =6, pinealectomy) and control group (n =6, sham operation). Seven days later, rats in both two groups were continuously fed for 33 days. ① Learning ability test: The learning ability of rats was tested by trisection Y-type maze and figured as attempting times. ② Expression of acetylcholinesterase (AchE) was detected by enzyme histochemistry and nNOS was measured by SABC method. ③ Quantitative analysis of AchE fibers: AchE fibers density in unit area (surface density) was surveyed with Leica Diaplan microscope and Leica Quantimet 500+ image analytic apparatus and quantitative parameter was set up for AchE fibers covering density (μm2) per 374 693.656 μm2, moreover, the AchE fibers density was measured in Ⅱ-Ⅳ layers of motor and somatosensory cortex (showing three layers per field of vision at one time), in radiative, lacunaria and molecular layers of CA1, CA2 and CA3 areas, and in lamina multiforms of dentate gyrus. Three tissue slices wer

关键词： Effects of melatonin on learning abilities cholinergic fibers and nitric oxide synthase expression in rat cerebral cortex nNOS

Ni-loaded Catalyst Containing Activated Clay for Maleic Anhydride Hydrogenation to Succinic Anhydride

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china Petroleum Processing & Petrochemical Technology 2011年第4期13卷 35-40页

作者： Tian Weiping Guo Shaofei Shi Li (The State Key Laboratory of Chemical Engineering, East china university of Science and Technology, shanghai 200237) E china Univ Sci & Technol State Key Lab Chem Engn Shanghai 200237 Peoples R China

In this work, the hydrogenation of maleic anhydride to succinic anhydride in the presence of 5 m%Ni/clay catalysts was investigated. These catalysts were characterized by X-ray diffraction （XRD）, H2 temperature programmed reduction （TPR） and thermogravimetric analysis （TGA） techniques. The XRD and TPR studies showed that Ni was present as Ni2＋ on the support, which indicated that there were no elemental nickel （Ni^0） and Ni203 species in the unreduced samples. Increasing of calcination temperature to 650 ℃ leads to destruction of the support structure observed in TGA, while the catalyst sample calcined at 550 ℃ exhibits better performances than other samples. The ideal conversion of maleic anhydride （97.14%） and selectivity of succinic anhydride （99.55%） were realized at a reaction temperature of 180 ℃ and a weight hourly space velocity of 4 h^-1 under a reaction pressure of 1 MPa.

关键词： maleic anhydride hydrogenation succinic anhydride nickel