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Photocatalytic performance of K2Ti6O13 whiskers to H2 evolution and cO2 photo-reduction

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Journal of Energy chemistry 2019年第10期28卷 18-28页

作者： L. F. Garay-Rodríguez L.M.Torres-Martínez E.Moctezuma Facultad de Ingeniería civil-Departamento de Ecomateriales y Energía Universidad Autónoma de Nuevo LeónAv. Universidad S/N Cd. UniversitariaC. P. 66455 San Nicolás de los GarzaNLMéxico Facultad de ciencias Químicas Universidad Autónoma de San Luis PotosíAv. Manuel Nava#6C. P.78290 San Luis PotosíSLPMéxico

K2Ti6O13 whiskers were synthesized by conventional sol-gel method, sono-chemical assisted and microwave assisted sol-gel method in order to obtain catalysts with different particle sizes and to modify their optical, textural and electrochemical properties. These modifications improved their photocatalytic activity for H2 evolution and cO2 photo-reduction. Long K2Ti6O13 whiskers prepared by ultrasound assisted sol-gel method are the most active photocatalysts for the hydrogen evolution reaction using pure water as reactant (U-SG, 10,065 μmol g^-1). In contrast, an opposite behavior was observed using a mixture of ethanol-water, where the highest activity was achieved by the shortest and less crystalline K2Ti6O13 whiskers (c-SG, 3,2871 μmol g^-1). In case of cO2 photo-reduction, long whiskers that were also prepared by the sono-chemical assisted sol-gel method were the most active to transform cO2 to formaldehyde, methane, methanol and hydrogen. The EFB value of this catalyst is located very close to the potential for formaldehyde production and favors the selectivity to this organic product.

关键词： K2Ti6O13 Sol-gel Whiskers Hydrogen evolution cO2 reduction

Production of Ag-ZnO powders by hot mechanochemical processing

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Transactions of Nonferrous Metals Society of china 2019年第2期29卷 365-373页

作者： D.GUZMáN c.AGUILAR P.ROJAS J.M.cRIADO M.J.DIánez R.ESPINOZA A.GUZMáN c.MARTínez Departamento de Ingeniería en Metalurgia Universidad de Atacama Departamento de Ingeniería Metalúrgica y de Materiales Universidad Técnica Federico Santa María Escuela de Dise?o Universidad Adolfo Ibá?ez Instituto de ciencias de Materiales de Sevilla C.S.I.C Departamento de ciencia de los Materiales Universidad de Chile Laboratorio de corrosión Instituto de QuímicaPontificia Universidad Católica de Valparaíso

Ag–cdO composites are still one of the most commonly used electrical contact materials in low-voltage applications owing to their excellent electrical and mechanical ***,considering the restriction on using cd due to its toxicity,it is necessary to find alternative materials that can replace these *** this study,the synthesis of Ag-ZnO alloys from Ag-Zn solid solutions was investigated by hot mechanochemical *** hot mechanochemical processing was conducted in a modified attritor mill at 138℃under flowing O2 at 1200 cm3/min for 3.0 *** microstructure and phase evolution were investigated using X-ray diffractometry,field emission gun scanning electron microscopy and transmission electron *** results suggest that it is possible to complete the oxidation of Ag-Zn solid solution by hot mechanochemical processing at a low temperature and short *** novel synthesis route can produce Ag-ZnO composites with a homogeneous distribution of nanoscale ZnO precipitates,which is impossible to achieve using the conventional material processing *** the fact that the fundamental approach to improving electric contact material performance resides in obtaining uniform dispersion of the second-phase in the Ag matrix,this new processing route could open the possibility for Ag-ZnO composites to replace non-environmentally friendly Ag-cdO.

关键词： Ag-ZnO nanocomposite electrical contact material powder synthesis milling

Mushroom Production as an Alternative for Rural Development in a Forested Mountainous Area

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Journal of Mountain Science 2014年第2期11卷 535-543页

作者： José *** José R.GONZáLEZ-OLABARRIA Juan MARTínez DE ARAGóN Departament de Producció Vegetal i ciència Forestal Universitat de Lleida-Agrotecnio Center (UdL-Agrotecnio).Av. Rovira Roure 191 E-25198 Lleida Spain centre Tecnològic Forestal de catalunya (cTFc-cEMFOR). ctra. de St. Lloren? de Morunys km 2 E-25280 Solsona Spain

Wild mushrooms are recognized as important non-wood forest products in mountainous ecosystems, but their real potential for generating rural economies has not been fully evaluated due to the difficulties in obtaining reliable productivity data, minimizing their true potential as contributor to rural economies. Mushroom yield models based on large data series from Pinus forest ecosystems in the region of catalonia(Spain), combined with data from the Spanish National Forest Inventory allow us to estimate the potential mushroom productivity by forest ecosystems. The results of 24,500 tons/yr of mushrooms of which 16,300 tons are classified as edible and 7,900 tons are commonly marketed demonstrate the importance of mushroom productions in catalonian pine forests, mostly located in mountainous areas where the development of agricultural activities is limited. Economic mushroom value is estimated at 48 million € for the edible mushroom and 32 million € for those corresponding to marketable yields, confirming the potential of this non-wood forest product. These production results and corresponding economic values provide a basis for the incorporation of wild mushrooms as significant non-wood forest products in the development of forest policies in mountainous areas.

关键词： Non-wood forest products Mushroom models National Forest Inventory Economic value Mushroom potential estimation

Branched Polyamines Functionalized with Proposed Reaction Pathways Based on <sup>1</sup>H-NMR, Atomic Absorption and IR Spectroscopies

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American Journal of Analytical chemistry 2014年第16期5卷 1090-1101页

作者： Vicente cervantes-Mejía Elizabeth Baca-Solis Judith caballero-jim.nez Rosario Merino-García Jesús cruz-Gatica Gabriela Moreno-Martínez Yasmi Reyes-Ortega chemical center Sciences Institute Autonomous University of Puebla Puebla México

Three novel branched polyamines N,N,N’,N’-tetrakis-[3((pyridine-2-methyl)-amine) propyl]-1,4- butanediamine (1), N,N,N’,N’-tetrakis-[N-((2-methylpyridine)ethyl)propanamide]ethylenediamine (2) and N,N,N’,N’-tetrakis-[3((2-hidroxibenziliden)-amine)propyl]-1,4-butanediamine (3), were synthesized starting from 2-pyridinecarboxaldeyde with DAB-Am-4 for 1, PAMAM G0 for 2 and from salicylaldehyde with DAB-Am-4 for 3. The pathway reactions have been proposed by 1H-NMR, IR and Atomic Absorption Spectroscopy. The optimal reaction time was set by IR spectroscopy following aldehyde? peak modification. 1 and 2 were obtained as both hydrochlorides and as free amines and 3 only as free imine. These polyamines were characterized by UV-Vis, IR, 1H-NMR and 13c-NMR and Mass Spectrometry.

关键词： Branched Polyamines Functionalization Reactions IR NMR Atomic Absorption Spectroscopy

Direct-fed microbes: A tool for improving the utilization of low quality roughages in ruminants

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Journal of Integrative Agriculture 2015年第3期14卷 526-533页

作者： Mona M Y Elghandour Abdelfattah Z M Salem Jose S Martínez castaeda Luis M camacho Ahmed E Kholif Juan c Vázquez chagoyán Faculty of Veterinary Medicine and Animal Science Autonomous University of the State of Mexico Faculty of Veterinary Medicine and Animal Science Autonomous University of Guerrero Dairy Science Department National Research Centre

For many years, ruminant nutritionists and microbiologists have been interested in manipulating the microbial ecosystem of the rumen to improve production efficiency of different ruminant species. Removal and restriction of antibiotics subtherapeutic uses from ruminant diets has amplified interest in improving nutrient utilization and animal performance and search for more safe alternatives. Some bacterial and fungal microorganisms as a direct-fed microbial（DFM） can be the most suitable solutions. Microorganisms that are commonly used in DFM for ruminants may be classified mainly as lactic acid producing bacteria（LAB）, lactic acid utilizing bacteria（LUB）, or other microorganism＇s species like Lactobacillus, Bifidobacterium, Enterococcus, Streptococcus, Bacillus, Propionibacterium, Megasphaera elsdenii and Prevotellabryantii, in addition to some fungal species of yeast such as Saccharomyces and Aspergillus. A definitive mode of action for bacterial or fungal DFM has not been established; although a variety of mechanisms have been suggested. Bacterial DFM potentially moderate rumen conditions, and improve weight gain and feed efficiency. Fungal DFM may reduce harmful oxygen from the rumen, prevent excess lactate production, increase feed digestibility, and alter rumen fermentation patterns. DFM may also compete with and inhibit the growth of pathogens, immune system modulation, and modulate microbial balance in the gastrointestinal tract. Improved dry matter intake, milk yield, fat corrected milk yield and milk fat content were obtained with DFM administration. However, the response to DFM is not constant; depending on dosages, feeding times and frequencies, and strains of DFM. Nonetheless, recent studies have supported the positive effects of DFM on ruminant performance.

关键词： direct-fed microbial(DFM) mode of action ruminants

Experience with postmortem computed tomography in the forensic analysis of the November 2015 Paris attacks

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Forensic Sciences Research 2020年第3期5卷 242-247页

作者： Laura W.de Jong Laurence Legrand Tania Delabarde Ghazi Hmeydia Myriam Edjlali lilia Hamza Joseph Benzakoun catherine Oppenheim Bertrand Ludes Jean-Francois Meder Department of Neuroradiology GHU Paris Psychiatrie et Neurosciences-Sainte-Anne HospitalUniversite de ParisParisFrance Inserm U1266 IMA-BrainInstitut de Psychiatrie et Neurosciences de ParisParisFrance Pole Universitaire d’Imagerie Post-Mortem Universite de ParisParisFrance Institut Medico-Legal de Paris ParisFrance Service d’Accueil des Urgences Hopital AvicenneBobignyFrance Universite de Paris BABELCNRSParisFrance

Several reports discuss the added value of postmortem computed tomography(PMcT)in the forensic analysis of mass fatality incidents(MFIs),such as the 2009 Victorian bushfires,the Grenfell tower disaster and the MH17 plane crash[1–5].In France,the first deployment of PMcT in an MFI took place during the forensic analysis of the November 2015 Paris terrorist attacks.

关键词： postmortem analysis disaster

Effect of cerium/lanthanum addition on microstructure and mechanical properties of Al7075 alloy via mechanical alloying and sintering

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Journal of Rare Earths 2016年第4期34卷 420-427页

作者： R.Pérez-Bustamante A.Reyna-cruz D.c.Acosta-Pena c.R.Santillán-Rodríguez J.A.Matutes-Aquino F.Pérez-Bustamante M.c.Maldonado-Orozco J.Aguilar-Santillán R.Martínez-Sánchez Research center in Advanced Materials(cIMA V) National Laboratory of NanotechnologyMiguel de Cervantes No.120C.P.31109ChihuahuaChih.Mexico Faculty of Engineering Autonomous University of Chihuahua(UACH)Circuito No.1 Nuevo Campus UniversitarioC.P.31 125ChihuahuaChih.Mexico Faculty of chemical Sciences Autonomous University of Chihuahua(UACH)Circuito No.1 Nuevo Campus UniversitarioC.P.31125ChihuahuaChih.Mexico Materials&Tools LLc 4118 E Washington CtGilbertAZUSA 85234

The effect of the Al-6ce-3La（AcL） on the microstructural behavior of the Al7075 was investigated. Materials were synthesized by mechanical alloying with variation in the AcL content and milling time. Products were characterized and studied in the as-milled condition and mechanically evaluated after sintering. The synergetic effect of milling time and AcL content in the modified materials led to a reduction in the particle size. Results from electron microscopy showed a homogeneous dispersion of ce/La phases up to 20 wt.% of AcL content after 10 h of milling. Mechanical evaluation under compressive test showed an improved performance for those alloys reinforced with 0.2 wt.% and 0.5 wt.% of AcL.

关键词： mechanical alloying rare earths aluminum microstructure sintering

Dynamically generated N* resonances from the interaction of two mesons and a baryon

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chinese Physics c 2009年第12期33卷 1302-1306页

作者： A. Martínez Torres K. P. Khemchandani E. Oset Departamento de Física Teórica and IFIc Centro Mixto Universidad de Valencia-CSIC Institutos de Investigación de Paterna Aptdo. 22085 46071 Valencia Spain centro de Física Teórica Departamento de Física Universidade de Coimbra P-3004-516 Coimbra Portugal

We have studied the ππN system and coupled channels by using of the Faddeev equations and two N* and one △ states, all of them with JP =1/2+, have been found in the formalism as dynamically generated states. In addition, signatures for a new N* resonance with JP =1/2+ are found around an energy of 1920 MeV in the three-body center of mass system.

关键词： Particle physics and field theory

Analyzing predictors of graft survival in patients undergoing liver transplantation with donors aged 70 years and over

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World Journal of Gastroenterology 2018年第47期24卷 5391-5402页

作者： Oscar caso-Maestro carlos jim.nez-Romero Iago Justo-Alonso Jorge calvo-Pulido David Lora-Pablos Alberto Marcacuzco-Quinto Félix cambra-Molero Alvaro García-Sesma Marina Pérez-Flecha carlos Munoz- Arce carmelo Loinaz-Segurola Alejandro Manrique-Municio Unit of HBP Surgery and Abdominal Organs Transplantation Department of General Surgery“12 de octubre” University HospitalMadrid 28041Spain clinical Research Department Consortium for Biomedical Research in Epidemiology and Public Health (CIBERESP)“12 de octubre” University HospitalMadrid 28041Spain

AIM To increase the number of available *** This is a single-center comparative analysis performed between April 1986 and May 2016. Two hundred and twelve liver transplantation(LT) were performed with donors ≥ 70 years old(study group). Then, we selected the first cases that were performed with donors control group).RESULTS Graft and patient survivals were similar between both groups without increasing the risk of complications, especially primary non-function, vascular complications and biliary complications. We identified 5 risk factors as independent predictors of graft survival: recipient hepatitis c virus(HcV)-positivity [hazard ratio(HR) = 2.35; 95% confidence interval(cI): 1.55-3.56; P = 0.00]; recipient age(HR = 1.04; 95%cI: 1.02-1.06; P = 0.00); donor age X model for end-stage liver disease(D-MELD)(HR = 1.00; 95%cI: 1.00-1.00; P = 0.00); donor value of serum glutamic-pyruvic transaminase(HR = 1.00; 95%cI: 1.00-1.00; P = 0.00); and donor value of serum sodium(HR = 0.96; 95%cI: 0.94-0.99; P = 0.00). After combining D-MELD and recipient age we obtained a new scoring system that we called DR-MELD(donor age X recipient age X MELD). Graft survival significantly decreased in patients with a DR-MELD score ≥ 75000, especially in HcV patients(77% vs 63% at 5 years in HcV-negative patients, P = 0.00; and 61% vs 25% at 5 years in HcV-positive patients; P = 0.00). cONcLUSION A DR-MELD ≥ 75000 must be avoided in order to obtain the best results in LT with donors ≥ 70 years old.

关键词： Liver transplantation Aged donors Old donors Marginal donors Donor age