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A three-Dimensional Prediction Method for thermal Diffusion

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China Ocean Engineering 1998年第3期13卷 309-321页

作者： Wang, LX Sun, YL Zheng, ly Ocean Univ Qingdao Inst Environm Oceanog Qingdao 266003 Peoples R China

A three-dimensional, first order turbulence closure, thermal diffusion model is described in this paper. the governing equations consist of an equation of continuity, three components of momentum, conservation equations for salt, temperature and subgridscale energy, and an equation of state. In the model, according to the hypothesis of Kolmogorov and Prandtl, the viscosity coefficient of turbulent flow of homogeneous fluid is related to the local turbulent energy, and the horizontal and vertical exchange coefficients of mass, heat and momentum are computed with the introduction of subgridscale turbulence energy. the governing equations are solved by finite difference techniques. this model is applied to the Jiaozhou bay to predict thermal pollution by the Huangdao power plant. An instantaneous tidal current field is computed, then the distribution of temperature increment is predicted, and finally the effect of wind stress on thermal discharge is discussed.

关键词： three-dimensional turbulence closure thermal diffusion model finite difference techniques subgridscale energy exchange coefficient temperature increment

Effect of Austenite Ageing on Martensitic Transformation

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Journal of Materials Science & Technology 1997年第6期13卷 508-514页

作者： Chen, QZ Wu, XF Wei, ly Ke, J Univ Sci & Technol Beijing Dept Mat Phys Beijing 100083 Peoples R China

the effect of austenite ageing on martensite transformation in an iron and nickel alloy was studied. Attention was paid to the variation of dislocation configurations in austenite before martensite transformation, the clusters or precipitates produced during austenite ageing and the alteration of dislocation configurations affect together the consequent martensite transformation. Dispersed fine clusters and precipitates cripple nucleus role of special dislocation configurations and drop M-s. Coarse precipitates make M-g rise again. Densely piled up dislocations in nuclei lead to rise of M-s. All the changes in austenite are of benefit to small martensite plates.

关键词： Iron alloys

Using fluorescence surrogates to track algogenic dissolved organic matter(AOM) during growth and coagulation/flocculation processes of green algae

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Journal of Environmental Sciences 2019年第5期31卷 311-320页

作者： Quang Viet ly Mi-Hee Lee Jin Hur Department of Environment & Energy Sejong University

Tracking the variation of the algogenic organic matter(AOM) released during the proliferation of green algae and subsequent treatment processes is crucial for constructing and optimizing control strategies. In this study, the potential of the spectroscopic tool was fully explored as a surrogate of AOM upon the cultivation of green algae and subsequent coagulation/flocculation(C/F) treatment processes using ZrCl_4 and Al_2(SO_4)_3. Fluorescence excitation emission matrix coupled with parallel factor analysis(EEM-PARAFAC) identified the presence of three independent fluorescent components in AOM, including protein-like(C1), fulvic-like(C2) and humic-like components(C3). Size exclusion chromatography(SEC) revealed that C1 in AOM was composed of large-sized proteins and aromatic amino acids. the individual components exhibited their unique characteristics with respect to the dynamic changes. C1 showed the highest correlation with AOM concentrations(R^2= 0.843) upon the C/F processes. C1 could also be suggested as an optical predictor for the formation of trihalomethanes upon the C/F processes. this study sheds a light for the potential application of the protein-like component(C1) as a practical surrogate to track the evolution of AOM in water treatment or wastewater reclamation systems involving Chlorella vulgaris green algae.

关键词： EEM-PARAFAC Enhanced coagulation Size exclusion chromatography Algal dissolved organic matter Trihalomethanes

Predicting shear strength of slender beams without reinforcement using hybrid gradient boosting trees and optimization algorithms

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Frontiers of Structural and Civil Engineering 2022年第10期16卷 1267-1286页

作者： thuy-Anh NgUYEN Hai-Bang ly Van Quan TRAN Department of Civil Engineering University of Transport TechnologyHanoi 100000Vietnam

Shear failure of slender reinforced concrete beams without stirrups has surely been a complicated occurrence that has proven challenging to adequately *** primary purpose of this work is to develop machine learning models capable of reliably predicting the shear strength of non-shear-reinforced slender beams(SB).A database encompassing 1118 experimental findings from the relevant literature was compiled,containing eight distinct *** Boosting(gB)technique was developed and evaluated in combination with three different optimization algorithms,namely Particle Swarm Optimization(PSO),Random Annealing Optimization(RA),and Simulated Annealing Optimization(SA).the findings suggested that gB-SA could deliver strong prediction results and effectively generalizes the connection between the input and output *** values and two-dimensional PDP analysis were then carried *** may use the findings in this work to define beam’s geometrical components and material used to achieve the desired shear strength of SB without reinforcement.

关键词： slender beam shear strength gradient boosting optimization algorithms

New Host Molecules with Imidazoliums as Functional Arms:Syntheses and Anion Recognition

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Chinese Journal of Chemistry 2002年第5期20卷 447-452页

作者： Yuan, Y Jiang, ZL gao, g Zhang, gL You, JS Xie, rg Sichuan Univ Dept Chem Chengdu 610064 Peoples R China Daxian Teachers Coll Dept Chem Sichuan 635000 Peoples R China Chinese Acad Sci Chengdu Inst Biol Chengdu 610041 Peoples R China

the bridged tri imidazoliums 3·3X --5·3X - (X -=PF - 6, Br -, I -) and bis imidazoliums 6·2PF - 6 were synthesized by N quaternization of imidazole derivative 1 in acetonitrile under reflux. UV spectroscopic titration experiments showed that the halide salts and hexafluorophosphate salts of these imidazoliums exhibited good recognition toward anions in water and in acetonitrile, respectively.

关键词： anion recognition imidazolium synthesis UV titration supramolecular chemistry

mi R-122 negatively correlates with liver fibrosis as detected by histology and FibroScan

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World Journal of gastroenterology 2015年第25期21卷 7814-7823页

作者： Tünde Halász gábor horváth gabriella Pár Klára Werling András Kiss Zsuzsa Schaff gábor Lendvai Second Department of Pathology Semmelweis University Department of Pathology Military Hospital Hepatology Center of Buda 1111 BudapestHungary First Department of Medicine University of Pécs Second Department of Internal Medicine Semmelweis University MTA-SE Tumor Progression Research group Semmelweis University

AIM: To investigate whether expression of selected mi RNAs obtained from fibrotic liver biopsies correlate with fibrosis ***: Altogether, 52 patients were enrolled in the study representing various etiologic backgrounds of fibrosis: 24 cases with chronic hepatitis infections(types B, C), 19 with autoimmune liver diseases(autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis, overlapping syndrome cases), and 9 of mixed etiology(alcoholic and nonalcoholic steatosis, cryptogenic cases). Severity of fibrosis was determined by both histologic staging using the METAVIR scoring system and noninvasive transient elastography. Following RNAisolation, expression levels of mi R-21, mi R-122, mi R-214, mi R-221, mi R-222, and mi R-224 were determined using Taq Man Micro RNA Assays applying mi R-140 as the reference. Selection of mi RNAs was based on their characteristic up- or downregulation observed in hepatocellular carcinoma. Relative expression of mi RNAs was correlated with fibrosis stage and liver stiffness(LS) value measured by transient elastography, as well as with serum alanine aminotransferase(ALT) ***: the expression of individual mi RNAs showed deregulated patterns in stages F1-F4 as compared with stage F0, but only the reduced level of mi R-122 in stage F4 was statistically significant(P lyzing mi RNA expression in relation to fibrosis, levels of mi R-122 and mi R-221 showed negative correlations with fibrosis stage, and mi R-122 was found to correlate negatively and mi R-224 positively with LS values(all P th mi R-21(P gative correlations were observed in the fibrosis samples of mixed etiology between mi R-122 and fibrosis stage and LS values(P the samples of chronic viral hepatitis, between mi R-221 and fibrosis stage(P th ALT values in the samples of autoimmune live

关键词： Expression FibroScan Liver fibrosis METAVIR microRNA miR-122

Photoinitiated Reaction of β-Bromonaphthalene with Pinacolone Ion in DMSO

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Chinese Chemical Letters 2000年第11期11卷 945-948页

作者： Chen, ZB Zhao, ly Zhang, Z Univ Shanxi Dept Chem Taiyuan 030006 Shanxi Peoples R China

the photoinitiated reaction of beta -bromonaphthalene with excess pinacolone enolate does not yield expected normal S(RN)1 product 1-beta -naphthyl-3,3-dimethyl-2-butanone, 3, but a more complex molecule 2.2-dimethyl-5-(1',1'-dimethylethyl)-6-beta -naphthyl-5-hexene-3-one, 4, deriving from it. the reaction is inhibited by m-dinitrobenzene and do not occur in the absence of light. Structure analysis of the product, along with other evidence, indicates a mechanism for this reaction, where addition of a further pinacolone molecule to carbonyl group of 3 and subsequent elimination of a water molecule would afford product 4, once the S(RN)1 substitution product 3 has formed.

关键词： Photoinitiated Reaction of MS Bromonaphthalene with Pinacolone Ion in DMSO

Decoding the genetic program of micronucleus formation: linking chromosomal instability to human disease

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Signal Transduction and Targeted therapy 2024年第7期9卷 2840-2842页

作者： Jörg Fahrer Division of Food Chemistry and Toxicology Department of ChemistryRPTU Kaiserslautern-Landau67663 KaiserslauternGermany

A recent study by Adams and colleagues published in Nature unveiled more than one hundred genes that are involved in micronucleus formation,1 which is a biomarker for genomic instability and associated with aging,cancer,and other disorders.2 As an outstanding achievement,the authors identified DSCC1(DNA Replication And Sister Chromatid Cohesion 1)as a critical gene protecting against early developmental defects,genomic instability,reduced proliferative capacity,cohesinopathy-related phenotypes,and tumor development in vivo.

关键词： chromosomal linking Replication

Nondestructive Evaluation of Ferroelectric Multilayer Capacitors Using Electromechanical Resonances

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Journal of Materials Science & Technology 1995年第2期11卷 114-118页

作者： SUN, HT WANg, HF ZHANg, ly YAO, X Xi'an Jiaotong Univ Xi'an China

Under the mechanically free and clamped boundary conditions, electromechanical resonances-of ceramic multilayer capacitors are calculated using vibration and piezoelectric equations. Multilayer capacitors made of ferroelectric BaTiO3 and Pb(Mp(1/3)Nb(2/3))O-3 ceramics have been used to examine the theoretical calculation. Frequency spectra of impedance and phase angle, capacitance and loss tangent of the capacitors under de bias fields are carefully measured. A sudden change around the resonant frequency is observed in these spectra. A damped resonance indicates a defective capacitor while an undamped resonance is corresponding to defect free. Experimental results suggest that it is possible to use the spectra as a real time nondestructive evaluation method.

关键词： Capacitors