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CALCULATION OF PENALTIES IN ALGORITHM OF MIXEDINTEGER PROGRAMMING SOLVING WITH REVISED duALSIMPLEX METHOD FOR BOUNDED VARIABLES

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Journal of Computational Mathematics 1999年第5期17卷 545-552页

作者： Wei, YM Hu, qh Chinese Acad Sci Inst Policy & Management Beijing 100080 Peoples R China Wuhan Inst Chem Technol Wuhan 430073 Peoples R China

The branch-and-bound method with the revised dual simplex for bounded variables is very effective in solving relatively large-size integer linear programming problems. This paper, based on the general forms of the penalties by Beale and Small and the stronger penalties by Tomlin, describes the modifications of these penalties used for the method of bounded variables. The same examples from Petersen are taken and the satisfactory results are shown in comparison with those obtained by Tomlin.

关键词： penalties stronger penalties the revised dual simplex method for bounded variables

Wave-Current Propagation over a Frictional Topography

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China Ocean Engineering 1998年第4期13卷 417-426页

作者： Zuo, qh Ding, BC Nanjing Hydraul Res Inst River & Harbour Dept Nanjing 210024 Peoples R China

In this paper the parabolic approximation model based on mild-slope equation is used to study wave propagation over a slowly varying and frictional topography under wave-current interaction. A governing equation considering the friction effects is derived by the authors for the first time. A simplified form for the rate of wave energy dissipation is presented on the basis of the wave-current action conservation equation and the bottom friction model given by Yoo and O'connor (1987). Examples reveal that the present computational method can be used for the calculation of wave elements for actual engineering projects with large water areas.

关键词： wave-current frictional topography refraction-diffraction

Crystal Structure of 5 ( l Menthyloxy) 3 Chloro 4 Pyrrolidinyl 2(5H) Furanone

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Chinese Journal of Structural Chemistry 1999年第2期18卷 35-38页

作者： Geng, Z Chen, qh Capital Normal Univ Dept Chem Beijing 100037 Peoples R China Beijing Normal Univ Dept Chem Beijing 100875 Peoples R China

The molecular structure of the title compound 5 ( l menthyloxy) 3 chloro 4 pyrrolidinyl 2(5H) furanone, C 18 H 28 ClNO 3(Ⅰ), has been determined by X ray diffraction at 296(1)K. The crystal is monoclinic with space group P2 1, a=9 457(3), b=10.413(3), c=9.525(2) , β=95.19(2)°, V=934(1)  3, Z=2, M r=341.88, D x =1.22 g/cm 3, μ =2.15 cm -1 , F(000)=368. The final R factor is 0 059, and R w is 0.065 for 1020 observed reflections with I≥3σ(I) . The absolute configuration at C(14) of the acetal carbon was proved to be S , taking into account the known configuration of 1R, 2S, 5R menthyl moiety. There are three rings in the molecule of this compound: the furanone ring, the pyrrolidine ring and the mentholoxy group ring. The franone ring is connected with the pyrrolidine ring and the mentholoxy ring by N atom and μ 2 O bridge atom respectively.

关键词： crystal structure absolute configuration Michael addition elimination reaction

ANALYSIS ON SMALL SCALE BRIDGING IN FIBROUS MONOLITHIC CERAMICS

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Acta Mechanica Solida Sinica 1999年第3期12卷 227-238页

作者： Wu, ZJ Cai, qh Tsing Hua Univ Dept Mech Engn Beijing 100084 Peoples R China

Based on shear lag model of interface between fiber and matrix, a new formula that relates the crack opening displacement and bridging force in fibrous monolithic ceramics was constructed under the framework of small scale bridging. This formula was applied to predict the fracture resistance or R-curve response of a three-point bending specimen made of fibrous monolithic ceramics. A parametric investigation on the influences of fiber volume fraction, fiber radius, characteristics of constituents, BN's fracture toughness and specimen's geometry on the bridging forces and fracture resistance in Si3N4/BN composite was carried out. The upper and lower limits of the R-curve of Si3N4/BN in small scale bridging were derived. This research revealed the role played by the above parameters in the fracture toughness of fibrous monolithic ceramics.

关键词： fibrous monolithic ceramics fiber bridging R-curve fracture toughness

Investigation of the Surface State of Zeolite HZSM-5 Pretreated with Toluene by Using Fast Atom Bombardment Mass Spectrometry (FABMS)

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Chinese Chemical Letters 1998年第7期9卷 671-674页

作者： Zhu, JH Xu, qh Nanjing Univ Dept Chem Nanjing 210093 Peoples R China

Toluene pretreatment caused many activated toluene species existing on the surface of zeolite HZSM-5, by which the activity of sample was increased. Moreover, variation in the surface Si+/Al+ ratio of HZSM-5 was sensi... 详细信息

关键词： zeolite HZSM-5 surface state FABMS toluene ethylation

Synthesis　and　Characterization　of　Tri(organotin)Substituted　Heteropolytungstates

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Chemical Research in Chinese Universities 1998年第1期14卷 6-11页

作者： Yang, qh Dai, HC Liu, JF NE Normal Univ Dept Chem Changchun 130024 Peoples R China

ＳｙｎｔｈｅｓｉｓａｎｄＣｈａｒａｃｔｅｒｉｚａｔｉｏｎｏｆＴｒｉ（ｏｒｇａｎｏｔｉｎ）ＳｕｂｓｔｉｔｕｔｅｄＨｅｔｅｒｏｐｏｌｙｔｕｎｇｓｔａｔｅｓＹＡＮＧＱｉ－ｈｕａ，ＤＡＩＨｕｉ－ｃｏｎｇ，ＬＩＵＪｉｎｇ－ｆｕ... 详细信息

ＳｙｎｔｈｅｓｉｓａｎｄＣｈａｒａｃｔｅｒｉｚａｔｉｏｎｏｆＴｒｉ（ｏｒｇａｎｏｔｉｎ）ＳｕｂｓｔｉｔｕｔｅｄＨｅｔｅｒｏｐｏｌｙｔｕｎｇｓｔａｔｅｓＹＡＮＧＱｉ－ｈｕａ，ＤＡＩＨｕｉ－ｃｏｎｇ，ＬＩＵＪｉｎｇ－ｆｕ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈｅｍ...

关键词： organotin)Substituted Heteropolytungstates Synthesis Tri Characterization

Crystal Structure of 5-(l-Menthyloxy)-3-Bromo-4-(R)-(+)-Methylbenzylamino-2(5H)-Furanone

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Chinese Journal of Structural Chemistry 1999年第2期18卷 32-34页

作者： Geng, Z Huang, B Chen, qh Capital Normal Univ Dept Chem Beijing 100037 Peoples R China Beijing Normal Univ Dept Chem Beijing 100875 Peoples R China

The crystal structure of the title compound 1, C 22 H 30 BrNO 3, was determined by X ray analysis at 296(1)K. The crystal belongs to othorhombic system, space group P2 12 12 1 with a=9.842(5), b=12.510(5), c=17.763(6) , V=2187(3)  3, Z=4, M r=436.37, D x =1.33 g/cm 3, μ =18.79 cm 1 , F(000) =912 and the final R=0.047 and R w=0.053 for 1429 observed reflections with I≥3σ(I). Structure analysis reveals that the absolute configuration at C 14 of the acetal carbon of the title compound is S.

关键词： crystal structure 2(5H) furanone absolute configuration.

Clinicopathologic study of primary intestinal B cell malignantlymphoma

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World Journal of Gastroenterology 1999年第6期5卷 538-540页

作者： Zhou Q Xu TR Fan qh Zhen ZX Nanjing Med Univ Affiliated Hosp 1 Dept Pathol Nanjing 210029 Jiangsu Prov Peoples R China

INTROduCTIONPrimary intestinal B cell lymphoma is one of the most common extra-nodal lymphomas, which includes two types: intestinal mucosa-associated lymphoid tissue lymphoma (IMALToma) and lymphomatous polyposis (LP). Both have characteristic pathologic features, immunophen-otypes and biological behaviors. In this article, twenty-five cases were retrospectively analyzed with regard to criteria of diagnosis and clinicopathologic characteristics.

关键词： lymphoma/pathology intestinal neoplasms/pathology intestinal neoplasms/diagnosis

Synthesis and characterization of La-containing SiMCM-41

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Chinese Science Bulletin 1997年第7期42卷 560-563页

作者： He, NY Bao, SL Xu, qh NANJING UNIV DEPT CHEMNANJING 210093PEOPLES R CHINA

FOR the reactions of larger molecules, the preparation of zeolites with large pore size has been a very important subject in zeolite chemistry. The mesoporous molecular sieves designated MCM-41 with pore size in the r... 详细信息

关键词： La-containing SiMCM-41 synthesis characterization hydrothermal stability.