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Oxygen Isotopic Fractionation in the Kaolinite-Water System during the Synthetic Process

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Journal of Minerals and Materials characterization and Engineering 2018年第4期6卷 507-516页

作者： E. caballero c. jim.nez de cisneros Instituto Andaluz de ciencias de la Tierra (UGR-cSIc) Armilla Spain

Oxygen isotope fractionation is studied during the synthesis of kaolinite under controlled conditions of temperature and time. Equilibrium conditions have been established and its relationship with temperature has been studied. Kaolinite was hydrothermally precipitated starting from non-crystalline aluminosilicate gels. The amount of kaolinite obtained increases up to a limited constant value and in all cases coexists with the amorphous starting gels. It can be seen that the data obtained at 48 hours of synthesis can be considered as quasi-equilibrium, since the total isotopic equilibrium has not been reached, only the sample obtained at 24 hours should be discarded for studies in equilibrium. This would allow us, with the samples obtained at 720 hours, to try to establish a relationship between isotopic fractionation and temperature, provided that we know the water in equilibrium with the synthesized kaolinite. Two equations have been obtained that show correlation coefficients with a high statistical significance.

关键词： Oxygen Isotopic Fractionation Kaolinite-Water System Isotopic Equilibrium

Multi-phase(Zr,Ti,cr)B_(2) solid solutions:Preparation,multi-scale microstructure,and local properties

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Journal of Advanced ceramics 2023年第2期12卷 414-431页

作者： Laura SILVESTRONI Nicola GILLI Alex SANGIORGI Alessandro cOROZZI Suzana FILIPOVIĆ Nina OBRADOVIĆ Laia ORTIZ-MEMBRADO Emilio jim.nez-PIQUÉ William G.FAHRENHOLTZ cNR-ISSMc Institute of ScienceTechnology and Sustainability for Ceramics(former ISTEC)Via Granarolo 6448018 FaenzaItaly cNR-IMM Institute for Microelectronics and MicrosystemsVia Gobetti 10140129 BolognaItaly Institute of Technical Sciences of SASA Knez Mihailova 35/IV11000 BelgradeSerbia Department of Materials Science and Engineering EEBEUniv.Politècnica de Catalunya-BarcelonaTECH.Avda.Eduard Maristany 1608019 BarcelonaSpain Department of Materials Science and Engineering Missouri University of Science and TechnologyRollaMO 65049USA

Multi-phase ceramics based on ZrB_(2),TiB_(2) and doped with crB_(2) and Sic were prepared by powder metallurgy and hot pressing to explore the possibility of obtaining multi-scale microstructures by super-saturation of complex(Zr,Ti,cr)B_(2) solid ***-shell structures formed in TiB_(2) grains,whereas ZrB_(2) appeared to form a homogeneous solid solution with the other *** of nano-inclusions within both micron-sized borides was assessed by transmission electron microscopy and thermodynamics elucidated the preferential formation of boride inclusions due to the specific sintering *** addition,atomic size factors explicated the precipitation of crB_(2) nano-particles into ZrB_(2)-rich grains and of ZrB_(2) nano-particles into TiB_(2)-rich *** hardness of the constituent phases measured by nanoindentation ranged from 36 to 43 GPa.

关键词： boride core-shell solid solution nanoindentation sintering

Heat transfer in a tapered fluidized bed of biomass particles with pulsed gas flow

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Particuology 2019年第1期17卷 2-14页

作者： Dening Jia Xiaotao Bi c. jim Lim Shahab Sokhansanj Atsushi Tsutsumi Department of chemical and Biological Engineering The University of British Columbia2360 East MallVancouverBCV6T 1Z3Canada Environmental Sciences Division Oak Ridge National LaboratoryOak RidgeTN 37831USA collaborative Research center for Energy Engineering Institute of Industrial ScienceThe University of Tokyo4-6-1 KomabaMeguro-kuTokyo 153-8505Japan

Bed-to-surface heat transfer of pure biomass particles in a pulsed fluidized bed with a tapered bottom section was investigated. Three biomass species — Douglas fir, pine, and switchgrass — were studied under various operating conditions. Their heat transfer coefficients were found to be closely associated with hydrodynamics dominated by gas pulsations. A higher superficial gas velocity generally yielded better gas–solid contact and higher heat transfer rates. A moderately increasing pulsation frequency promoted convective heat transfer of particles but also reduced pulsation intensity, leading to undesired flow behaviours such as channelling and partial defluidization. The study of the pulsation duty cycle revealed that, for cohesive particles, a smaller duty cycle was preferred to generate powerful pulsations to break up inter-particle forces. Moreover, a duty cycle increase allowed higher gas throughput as long as a suitable fluidization was maintained. The addition of finer particles to a coarse fraction increased particle mobility, and subsequently heat transfer, which also explained the higher heat transfer coefficients of switchgrass as it contained more fines compared with fir and pine. Experimental results in the tapered bed were also compared with those of non-tapered geometry where a 10%–20% increase in heat transfer was observed.

关键词： Fluidized bed Gas pulsations Tapered column Heat transfer Biomass

Effects of the mass and volume shrinkage of ground chip and pellet particles on drying rates

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Particuology 2018年第3期16卷 1-9页

作者： Hamid Rezaei Shahab Sokhansaj c. jim Lim Anthony Lau Xiaotao Bi chemical and Biological Engineering Department University of British Columbia Vancouver BC V6T 1Z3 Canada Environmental Science Division Oak Ridge National Laboratory Oak Ridge TN 37381 USA

The effects of varying the mass and volume of ground chip and pellet particles on the particle drying rate were analyzed. Samples of whole pellets and chips were hammer milled using a 3.2 mm screen and the ground chip and pellet particles were found to have similar size distributions, although the pellet particles were denser and more spherical than the chip particles. Prior to drying, water was added to the particles to obtain 0.10, 0.30, 0.50, 0.70, and 0.90 moisture contents （on a dry mass basis）. The moistened particles were subsequently dried in a constant temperature thin layer dryer set at 50,100, 150, or 200 ~c under dry pure nitrogen, dry compressed air, or atmospheric air. The chip and pellet particles exhibited similar degrees of shrinkage, but the pellet particles underwent a greater reduction in their bulk volume during drying. It appears that the more spherical pellet particles are prone to shrinkage in more than one direction, whereas the needle-like chip particle shrink only in one direction. A variable radius first order drying model was found to fit the experimental data better than a fixed radius model.

关键词： Moisture loss Particle density Ground chip Ground pellet Particle shrinkage Bulk shrinkage

New therapeutic options opened by the molecular classification of gastric cancer

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World Journal of Gastroenterology 2018年第18期24卷 1942-1961页

作者： Mihaela chivu-Economescu lilia Matei Laura G Necula Denisa L Dragu coralia Bleotu carmen c Diaconu Department of cellular and Molecular Pathology Stefan S. Nicolau Institute of Virology Nicolae cajal Institute Titu Maiorescu University

Gastric cancer(Gc) is one of the most lethal and aggressive cancers, being the third cause of cancer related death worldwide. Even with radical gastrectomy and the latest generation of molecular chemotherapeutics, the numbers of recurrence and mortality remains high. This is due to its biological heterogeneity based on the interaction between multiple factors, from genomic to environmental factors, diet or infections with various pathogens. Therefore, understanding the molecular characteristics at a genomic level is critical to develop new treatment strategies. Recent advances in Gc molecular classification provide the unique opportunity to improve Gc therapy by exploiting the biomarkers and developing novel targeted therapy specific to each subtype. This article highlights the molecular characteristics of each subtype of gastric cancer that could be considered in shaping a therapeutic decision, and also presents the completed and ongoing clinical trials addressed to those targets. The implementation of the novel molecular classification system will allow a preliminary patient selection for clinical trials, a mandatory issue if it is desired to test the efficacy of a certain inhibitor to the given target. This will represent a substantial advance as well as a powerful tool for targeted therapy. Nevertheless, translating the scientific results into new personalized treatment opportunities is needed in order to improve clinical care, the survival and quality of life of patients with Gc.

关键词： Gastric cancer Molecular classification Immunotherapy Targeted therapy clinical trials

How to express tumours using membrane systems

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Progress in Natural Science:Materials International 2007年第4期17卷 449-457页

作者： Miguel A. Gutiérrez-Naranjo Mario J. Pérez-jim.nez Agustín Riscos-Núez Francisco J. Romero-campero Department of computer Science and Artificial Intelligence University of Seville Avda. Reina Mercedes s/n41012SevillaSpain

In this paper we discuss the potential usefulness of membrane systems as tools for modelling tumours. The approach is followed both from a macroscopic and a microscopic point of view. In the first case, one considers the tumour as a growing mass of cells, focusing on its external shape. In the second case, one descends to the microscopic level, studying molecular signalling pathways that are crucial to determine if a cell is cancerous or not. In each of these approaches we work with appropriate variants of membrane systems.

关键词： tumour membrane system modeling.

Arylhydrazones Derivatives containing a Benzothiazole Moiety, Efficient Ligands in the Palladium-catalyzed Mizoroki-Heck and Suzuki-Miyaura cross-coupling Reactions under IR Irradiation

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chinese Journal of chemistry 2017年第12期35卷 1881-1888页

作者： Fernando Ortega-jim.nez José Guillermo Penieres-carrillo José Guadalupe López-cortés M. carmen Ortega-Alfaro Selene Lagunas-Rivera Departamento de cieneias Qulmicas Facultad de Estudios Superiores Cuautitlān-UNAM Campo i Avenida lro. de Mayo s/n Cuautitlán Izcalli C.P. 54740 Estado de México México Instituto de Qulmiea UNAM Circuito Exterior Ciudad Universitaria Coyoacán C.P. 04360 Cuidad de México México Instituto de ciencias Nucleares UNAM Circuito Exterior Ciudad Universitaria Coyoacán C.P. 04360 Ciudad de México México catedrático cONA cyT-TecNM-Instituto Tecnológico de Tuxtla Gutiérrez Carretera Panamericana Km 1080 Col Juan Crispin Tuxtla Gutiérrez C.P. 29050 Chiapas México

A simple arylhydrazone containing the benzothiazole moiety which may be used as an efficient ligand in the palladium-catalyzed Mizoroki-Heck and Suzuki-Miyaura cross-coupling reactions, under infrared irradiation as an alternative source of energy, is presented. The reactions proceeded with extremely high efficiency under mild conditions and produced very good yields.

关键词： arylhydrazones palladium-catalyzed cross-coupling reaction IR-irradiation

Use of carbon nanotubes for strain and damage sensing of epoxy-based composites

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International Journal of Smart and Nano Materials 2012年第2期3卷 152-161页

作者： J.Rams M.Sánchez A.Ureña A.jim.nez-Suárez M.campo A.Güemes Materials Science and Engineering Rey Juan Carlos UniversityTulipan s/nMostoles28933 MadridSpain ETSIA Universidad Politécnica de MadridPza.de Cardenal Cisneros 328040 MadridSpain

The interest in structural health monitoring of carbon fiber-reinforced polymers using electrical methods to detect damage in structures is growing because once the material is fabricated the evaluation of strain and damage is simple and *** order to obtain the conductivity,the polymer matrix must be conductive and the use of nanoreinforcement seems to be the most feasible *** this work,the behavior of nanoreinforced polymer with carbon nanotubes(cNTs)and composites with glass and carbon fibers with nanoreinforced matrices was *** composites were evaluated in tensile tests by simultaneously measuring stress,strain and *** elastic deformation,a linear increase in resistance was observed and during fracture of the composite fibers,stronger and discontinuous changes in the resistivity were *** other factors,the percentage of nanotubes incorporated in the matrix turned out to be an important factor in the sensitivity of the method.

关键词： carbon nanotube nanoreinforcement structural health monitoring strain sensing carbon fiber

Octogenarian liver grafts:Is their use for transplant currently justified?

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World Journal of Gastroenterology 2017年第17期23卷 3099-3110页

作者： carlos jim.nez-Romero Felix cambra Oscar caso Alejandro Manrique Jorge calvo Alejandro Marcacuzco Paula Rioja David Lora Iago Justo HPB Surgery and Abdominal Organ Transplantation Unit University Hospital“Doce de Octubre” Department of Surgery Facultad de Medicina

AIMTo analyse the impact of octogenarian donors in liver *** present a retrospective single-center study, performed between November 1996 and March 2015, that comprises a sample of 153 liver transplants. Recipients were divided into two groups according to liver donor age: recipients of donors ≤ 65 years (group A; n = 102), and recipients of donors ≥ 80 years (group B; n = 51). A comparative analysis between the groups was performed. Quantitative variables were expressed as mean values and SD, and qualitative variables as percentages. Differences in properties between qualitative variables were assessed by χ2 test. comparison of quantitative variables was made by t-test. Graft and patient survivals were estimated using the Kaplan-Meier ***, 3 and 5-year overall patient survival was 87.3%, 84% and 75.2%, respectively, in recipients of younger grafts vs 88.2%, 84.1% and 66.4%, respectively, in recipients of octogenarian grafts (P = 0.748). One, 3 and 5-year overall graft survival was 84.3%, 83.1% and 74.2%, respectively, in recipients of younger grafts vs 84.3%, 79.4% and 64.2%, respectively, in recipients of octogenarian grafts (P = 0.524). After excluding the patients with hepatitis c virus cirrhosis (16 in group A and 10 in group B), the 1, 3 and 5-year patient (P = 0.657) and graft (P = 0.419) survivals were practically the same in both groups. Multivariate cox regression analysis demonstrated that overall patient survival was adversely affected by cerebrovascular donor death, hepatocarcinoma, and recipient preoperative bilirubin, and overall graft survival was adversely influenced by cerebrovascular donor death, and recipient preoperative *** standard criteria for utilization of octogenarian liver grafts are: normal gross appearance and consistency, normal or almost normal liver tests, hemodynamic stability with use of curement, intensive care unit s

关键词： Older liver Donor age Marginal liver Liver transplant Aging liver