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particuology 2014年第4期12卷 129-137页

作者： Wojciech p.Adamczyk Adam Klimanek Ryszard A.Biaecki gabriel Wecel pawe Kozolub Tomasz Czakiert Institute of Thermal Technology Silesian University of Technology44-100 GliwiceKonarskiego 22Poland Institute of Advanced Energy Technologies Czestochowa University of TechnologyCzestochowaPoland

particle transport phenomena in small-scale circulating fiuidized beds （CFB） can be simulated using the Euler-Euler, discrete element method, and Euler-Lagrange approaches. In this work, a hybrid Euler-Lagrange model known as the dense discrete phase model （DDpM）, which has common roots with the multiphase particle-in-cell model, was applied in simulating particle transport within a mid-sized experimental CFB facility. Implementation of the DDpM into the commercial ANSYS Fluent CFD package is relatively young in comparison with the granular Eulerian model. For that reason, validation of the DDpM approach against experimental data is still required and is addressed in this paper. Additional difficulties encountered in modeling fluidization processes are connected with long calculation times. To reduce times, the complete boiler models are simplified to include just the combustion chamber. Such simplifications introduce errors in the predicted solid distribution in the boiler. To investigate the conse- quences of model reduction, simulations were made using the simplified and complete pilot geometries and compared with experimental data. All simulations were performed using the ANSYSFLUENT 14.0 package. A set of user defined functions were used in the hybrid DDpM and Euler-Euler approaches to recirculate solid particles.

关键词： particle Multiphase flow CFD particulate processes CFB Fluidized bed

Numerical analyses of pillar behavior with variation in yield criterion,dilatancy, rock heterogeneity and length to width ratio

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 46-60页

作者： Sankhaneel Sinha gabriel Walton Colorado School of Mines

With recent advances in numerical modeling, design of underground structures increasingly relies on numerical modeling-based analysis approaches. While modeling tools like the discrete element method(DEM) and the combined finite-discrete element method(FDEM) are useful for investigating small-scale damage processes, continuum models remain the primary practical tool for most field-scale *** results obtained from such models are significantly dependent on the selection of an appropriate yield criterion and dilation angle. Towards improving its capabilities in handling mining-related problems, the authors have previously developed a new yield criterion(called progressive S-shaped criterion). The focus of the current study is to demonstrate its use in modeling rock pillars through a comparative analysis against four other yield criteria. In addition to the progressive S-shaped criterion,only one out of the four other criteria predicted a trend in strength consistent with an empirical pillar strength database compiled from the literature. Given the closely-knit relationship between yield criteria and dilation angle in controlling the overall damage process, a separate comparison was conducted using a mobilized dilation model, a zero degree dilation angle and a constant non-zero dilation angle. This study also investigates the impact of meso-scale heterogeneity in mechanical properties on the overall model response by assigning probability distributions to the input parameters. The comparisons revealed that an isotropic model using a combination of progressive S-shaped criterion and mobilized dilation angle model is sufficient in capturing the behaviors of rock pillars. Subsequently, the pillar model was used to assess the effect of L/W(length/width) ratio on the peak strength.

关键词： Rock pillars progressive S-shaped criterion Numerical modeling

Effect of logging on rodent scatter-hoarding dynamics in tropical forests:implications for plant recruitment

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Integrative Zoology 2011年第2期6卷 74-80页

作者： gabriel GUTIéRrez-GRANADOS Department of Zoology Institute of BiologyNational Autonomous University of MexicoMexico DFMexico

The present study tested the hypothesis that logging affects the scatter-hoarding behavior of rodents,which,in turn,negatively affects the quantity and quality of pouteria campechiana(Sapotaceae)seed dispersal.A series of seed stations was established in logged and unlogged forests of ejido Senor,Yucatan peninsula,and comparisons were made between logged and unlogged forests in terms of:(i)seed removal;(ii)number of seeds hoarded;(iii)hoarding distance;and(iv)the number of recruits and the survival of hoarded *** number of both hoarded and removed seeds was significantly higher in unlogged ***,the mean distance of hoarding was greater in unlogged compared with logged *** recruitment and survival were present in both logged and unlogged sites,there were more surviving seedlings in unlogged *** data indicate that both the quantity and quality of seed dispersal are negatively affected by logging because of a change in the rodent scatter-hoarding *** changes suggest that plant-animal interactions are crucial to the understanding of the ecology and conservation of managed tropical forests.

关键词： Dasyprocta punctata seed caching timber extraction Yucatan peninsula

Recent progress on isospin breaking corrections and their impact on the muon g-2 value

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Chinese physics C 2010年第6期34卷 712-717页

作者： gabriel López Castro Departamento de Física CinvestavApartado Postal 14-74007000 MxicoD.F Mxico

We describe some recent results on isospin breaking corrections which are of relevance for predictions of the leading order hadronic contribution to the muon anomalous magnetic moment aμ^*** when using τ lepton data. When these corrections are applied to the new combined data on the π^±π^0 spectral function, the prediction for aμ^*** based on τ lepton data gets closer to the one obtained using e^＋e^- data.

关键词： isospin breaking tau decays muon magnetic moment radiative corrections

DEM speedup: Stiffness effects on behavior of bulk material

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particuology 2014年第1期12卷 107-112页

作者： Stef Lommen Dingena Schott gabriel Lodewijks Department of Maritime and Transport Technology Delft University of Technology

A number of techniques exist for minimizing the computational cost of discrete element simulations （DEMs）. One such method is a reduction of particle stiffness, which allows for bigger time steps and therefore fewer iterations in a simulation. However, the limits and drawbacks of this approach are still unclear, and may lead to invalid results. This paper investigates the effect of a stiffness reduction on bulk behavior by examining three case studies. Two cases demonstrate that particle stiffness can be reduced without affecting the bulk material behavior, whereas the third test shows that a stiffness reduction influences the bulk behavior.

关键词： Discrete element methodSpeedupStiffness reductionLimitOverlap

Recovery of carbon monoxide from flue gases by reactive absorption in ionic liquid imidazolium chlorocuprate(I): Mass transfer coefficients

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Chinese Journal of Chemical Engineering 2015年第5期23卷 769-774页

作者： gabriel Zarca Inmaculada Ortiz Ane Urtiaga Department of Chemical and Biomolecular Engineering Universidad de Cantabria Av. Los Castros s/n.

Recovery of carbon monoxide from flue gases by selective absorption of carbon monoxide in an imidazolium chlorocuprate（l） ionic liquid is considered in this work as an alternative to the use of molecular volatile solvents such as aromatic hydrocarbons. The present work evaluates the CO mass transfer rates from the gas phase to the ionic liquid solutions in the absence of chemical reaction. To that end, carbon dioxide was employed as an inert model gas and absorption experiments were performed to assess the influence of different process variables in a batch reactor with fiat gas-liquid interface. The experimental mass transfer coefficients showed significant var- iation with temperature, （3.4-10.9） × 10^-7 m·s^-1 between 293 and 313 K; stirring speed, （10.2- 33.1）× 10^-7 m.s 1 between 100 and 300 r·min^-1; and concentration of copper（1）, （6.6-10.2） × 10^-7 m·s^-1 between 0.25 and 2 mol· L^- 1. In addition, the mass transfer coefficients were eventually found to follow a poten- tial proportionality of the type kL ∝μ^-0.5 and the dimensionless correlation that makes the estimation of the mass transfer coefficients possible in the studied range of process variables was obtained： Sh=10^-2.64 Re^1.07 , Sc^0.75,These results constitute the first step in the kinetic analysis of the reaction between CO and imidazolium chlorocuprate（I） ionic liquid that determines the design of the separation units.

关键词： Carbon monoxide Ionic liquid Copper(I)Reactive absorption Mass transfer kinetics Mass transfer coefficient Carbon dioxide

Hepatitis C virus-associated B cell non-Hodgkin's lymphoma

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World Journal of Gastroenterology 2016年第27期22卷 6214-6223页

作者： Romeo-gabriel Mihaila Faculty of Medicine 'Lucian Blaga' University of Sibiu 500169 Sibiu Romania Hematology Department Emergency County Clinical Hospital Sibiu 550245 Sibiu Romania

The hepatitis C virus (HCV) infected patients are prone to develop bone marrow or various tissue infiltrates with monoclonal B cells, monoclonal B lymphocytosis or different types of B cell non-Hodgkin’s lymphoma (BCNHL), of which the most common are splenic marginal zone BCNHL, diffuse large BCNHL and follicular lymphoma. The association between chronic HCV infection and non Hodgkin’s lymphoma has been observed especially in areas with high prevalence of this viral infection. Outside the limitations of some studies that have been conducted, there are also geographic, environmental, and genetic factors that contribute to the epidemiological differences. Various microenvironmental signals, such as cytokines, viral antigenic external stimulation of lymphocyte receptors by HCV antigens, and intercellular interactions contribute to B cell proliferation. HCV lymphotropism and chronic antigenic stimulation are involved in B-lymphocyte expansion, as mixted cryoglobulinemia or monoclonal gammopathy of undetermined significance, which can progress to BCNHL. HCV replication in B lymphocytes has oncogenic effect mediated by intracellular HCV proteins. It is also involved in an important induction of reactive oxygen species that can lead to permanent B lymphocyte damage, as DNA mutations, after binding to surface B-cell receptors. post-transplant lymphoproliferative disorder could appear and it has a multiclonal potentiality that may develop into different types of lymphomas. The hematopoietic stem cell transplant made for lymphoma in HCV-infected patients can increase the risk of earlier progression to liver fibrosis and cirrhosis. HCV infected patients with indolent BCNHL who receive antiviral therapy can be potentially cured. Viral clearance was related to lymphoma response, fact that highlights the probable involvement of HCV in lymphomagenesis. Direct acting antiviral drugs could be a solution for the patients who did not tolerate or respond to interferon,

关键词： Chemotherapy Cryoglobulinemia Direct acting antiviral drugs Hepatitis C virus Hepatocytolysis Interferon Liver transplantation Liver dysfunction Non-Hodgkin’ s lymphoma Rituximab

Enhancement of the Antigenotoxic and Antioxidant Actions of Eugenol from Spice Clove and the Stabilizer Gum Arabic on Colorectal Carcinogenesis

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Food and Nutrition Sciences 2024年第1期15卷 71-100页

作者： Nayanna de Oliveira Ramos Melo Lucas gabriel da Costa Marques Humberto Maia Costa Neto Matheus De Sousa Silva Francisco Vagnaldo Fechine Jamacaru Bruno Coêlho Cavalcanti Antônio Adailson De Sousa Silva Conceição Aparecida Dornelas postgraduate program in Medical-Surgical Sciences School of Medicine Federal University of Ceará Fortaleza Brazil School of Medicine Federal University of Ceará Fortaleza Brazil Nucleus of Research and Development of Medicines (NpDM) Laboratory of Pharmacology and Preclinical Research School of Medicine Federal University of Ceará Fortaleza Brazil Nucleus for Research and Development of Medicines (NpDM) National Laboratory of Experimental Oncology Federal University of Ceará Fortaleza Brazil postgraduate program in pathology and Medical-Surgical Sciences School of Medicine Federal University of Ceará Fortaleza Brazil

Spices are defined as any aromatic condiment of plant origin used to alter the flavor and aroma of foods. Besides flavor and aroma, many spices have antioxidant activity, mainly related to the presence in cloves of phenolic compounds, such as flavonoids, terpenoids and eugenol. In turn, the most common uses of gum arabic are in the form of powder for addition to soft drink syrups, cuisine and baked goods, specifically to stabilize the texture of products, increase the viscosity of liquids and promote the leavening of baked products (e.g., cakes). Both eugenol, extracted from cloves, and gum arabic, extracted from the hardened sap of two species of the Acacia tree, are dietary constituents routinely consumed virtually throughout the world. Both of them are also widely used medicinally to inhibit oxidative stress and genotoxicity. The prevention arm of the study included groups: Ia, IIa, IIIa, Iva, V, VI, VII, VIII. Once a week for 20 weeks, the controls received saline s.c. while the experimental groups received DMH at 20 mg/kg s.c. During the same period and for an additional 9 weeks, the animals received either water, 10% GA, EUG, or 10% GA + EUG by gavage. The treatment arm of the study included groups Ib, IIb, IIIb e IVb, IX, X, XI, XII). Once a week for 20 weeks, the controls received saline s.c. while the experimental groups received DMH at 20 mg/kg s.c. During the subsequent 9 weeks, the animals received either water, 10% GA, EUG or 10% GA + EUG by gavage. The novelty of this study is the investigation of their use alone and together for the prevention and treatment of experimental colorectal carcinogenesis induced by dimethylhydrazine. Our results show that the combined use of 10% gum arabic and eugenol was effective, with antioxidant action in the colon, as well as reducing oxidative stress in all colon segments and preventing and treating genotoxicity in all colon segments. Furthermore, their joint administration reduced the number of aberrant crypts and th

关键词： Eugenol Gum Arabic Carcinogenesis Oxidative Stress Genotoxicity

Sexual differences in weaponry and defensive behavior in a neotropical harvestman

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Current Zoology 2019年第5期65卷 553-558页

作者： Julio M.G.SEGOVIA gabriel p.MURAYAMA Rodrigo H.WILLEMART Laboratorio de Ecologia Sensorial e Comportamento de Artropodes Escolade ArtesCiencias e Humanidades da Universidade de Sao PauloSao PauloBrazil programa de pos-Graduaqao em Zoologia Instituto de BiocienciasUniversidade de Sao PauloSao PauloBrazil programa de pos-Graduaqao em Ecologia e Evoluqao Universidade Federal de Sao PauloSao PauloBrazil

Sexual differences in morphology can evolve by sexual selection and/or natural *** some species,only males have morphological structures that are used as *** some weapons may also be used for defensive purposes,males and females may behave differently towards *** some species of harvestmen(Arachnida and Opiliones),males have sharp apophyses("spines")on their 4th pair of legs whereas females lack *** apophyses are used in malemale fights and in antipredatory *** harvestmen antipredatory repertory also encompasses passive defenses such as thanatosis(death feigning),retaliation(attack on predators),and chemical *** to the sexual differences on weaponry,we hypothesized that males and females of Mischonyx cuspidatus(Gonyleptidae)rely on different defensive *** experimentally induced males and females to perform 3 defensive behaviors:thanatosis,pinching with legs,and chemical *** predicted that females would engage more in passive and chemical defenses than males,whereas males would rely more on retaliation than *** expected,females performed thanatosis more often than ***,males performed retaliation more often than *** did not find differences in the rate of chemical defense use between the *** study provides evidence that due to sexual dimorphism,alternative antipredatory behaviors may have been selected in the different sexes in ***.

关键词： Arachnida death feigning nipping thanatosis weapon Opiliones

probabilistic transitions for p systems

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progress in Natural Science:Materials International 2007年第4期17卷 432-441页

作者： gabriel Ciobanu Laura Cornǎcel "A. I. Cuza" University Faculty of Computer ScienceBlvd. Carol I No. 11700506 IasiRomania Romanian Academy Institute of Computer ScienceBlvd. Carol I No.8700505 IasiRomania

In this paper we use the abstract syntax and the structural operational semantics of the p systems given in [ 1 ], and add probabilities to the rules and to the communication targets. We take into account the number of possible combinations of rules which can be applied in a computation step, as well as the consumption degree of the current resources.

关键词： probabilistic transition p systems.