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Journal of Wuhan University of Technology(Materials Science) 2018年第6期33卷 1293-1297页

作者： KESHTKAR Javad VARGAS GARCIA jorge Roberto galaviz perez jorge MARTINEZ TRINIDAD José Escuela Superior de Ingenieria Mecánica y Eléctrica Instituto Politécnico NacionalMéxico07738CDMXMéxico Escuela Superior de Ingenieria Quimica e Industrias Extractivas Instituto Politécnico NacionalMéxico07738CDMXMéxico Universidad Juárez Autònoma de Tabasco DivisiònAcadémica Multidisciplinaria de Jalpa de MéndezRibera AltaJalpa de MéndezTabasco86205México

Al-doped ZnO(AZO) powders were prepared by using metal chloride precursors and the sol-gel technique. IR peaks observed at 1590 cm-1 and 1620 cm-1indicated the formation of metal chelate as a consequence of the addition of acetylacetone to the metal chloride solution. TG-DSC analysis of the AZO gels confirmed the formation of metal chelate as evidenced by the development of several weight loss peaks accompanied by the introduction of new endothermic peaks. The resulting AZO gels were annealed at 500, 600, and 800 ℃ to study the effect of annealing temperature. XRD and SEM results showed that crystallization of AZO gels takes place around 600 ℃. Hexagonal wurtzite structure was identified as the main phase for all the samples. In addition, small shift of the XRD(002) peak coupled with XPS results from the AZO powders confirmed the successful doping of the ZnO powders. Micron sized rod-like AZO powders were uniform in dimension and morphology and remained stable even at 800 ℃.

关键词： aluminum doped ZnO rod-like metal chloride sol gel acetylacetone

Efficient removal of the recalcitrant metamizole contaminant from drinking water by using a CaLaCoO_(9) perovskite supported on recycled polyethylene

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Journal of Environmental Sciences 2024年第2期136卷 56-67页

作者： Ernesto Valadez-Renteria Christian perez-Carrasco Dulce Yolotzin Medina-Velazquez Vicente Rodriguez-Gonzalez jorge Oliva CONACYT-División de Materiales Avanzados Instituto Potosino de Investigación Científica y Tecnológica A.C.San Luis PotosíSLP 78216México División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana AzcapotzalcoCol.Reynosa-TamaulipasC.P.MéxicoDF 02200México

Metamizole(MZ)is a widely used anti-inflammatory *** to its common use,this contaminant is found in sewage and *** order to reduce the contamination produced by the MZ,we fabricated in this work a photocatalytic composite using recycled polyethylene(RPE)and the CaLaCoO_(9)(LCCO)*** nanoparticles had a microplate-like morphology and sizes of 1.4–5.5μm according to the analysis of *** photocatalytic properties of the LCCO powders were evaluated under ultraviolet-visible(UV-Vis)irradiation and found a removal efficiency of 96%.When the RPE+LCCO composite was employed for the photocatalytic degradation of MZ,a maximum degradation of 92.5%was *** influence of the pH on the photocatalytic activity was also studied and found that an initial pH=3 produced a total degradation of MZ after 240 min of UV-Vis ***,three reuse cycles were carried out for the pure LCCO powders and for the RPE+LCCO composites and found that the maximum loss of degradation was 5%.Furthermore,scavenger experiments demonstrated that the super oxide and hydroxyl radicals are formed during the photocatalytic reaction and were responsible for the degradation of ***,the X-ray photoelectron-spectroscopy and Raman analysis demonstrated the formation of defects(oxygen vacancies),those ones delayed the electron-hole recombination,which in turn,enhanced the degradation of the ***,the studies performed in this work proved that composites made with recycled plastics and LCCO perovskites are a low-cost and feasible alternative for the cleaning of water sources polluted with pharmaceutical compounds.

关键词： Photocatalysis Metamizole Pharmaceutical contaminant UV-Vis irradiation Perovskite

The “Brain Stress Timing” phenomenon and other misinterpretations of randomized clinical trial on aneurysmal subarachnoid hemorrhage

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Neural Regeneration Research 2019年第8期14卷 1364-1366页

作者： Rafael Martinez-perez Natalia Rayo Agustin Montivero jorge Marcelo Mura Division of Neurosurgery Institute of Clinical Neurosciences Universidad Austral de Chile Valdivia Chile Division of Cerebrovascular and Skull Base Neurosurgery Institute of Neurosurgery Dr Asenjo Santiago Chile Western University London ON Canada

Clipping and coiling are currently the two alternatives in treatment of ruptured cerebral aneurysms. In spite of some meritorious analysis, further discussion is helpful to understand the actual state of art. Retreatment and rebleeding rates clearly favors clipping, although short-term functional outcome seems to be beneficial for clipping, while this different is not such if we perform the comparison at a longer follow up. Longterm follow ups and cost analysis are mandatory to have a clear view of the current picture in treatment of subarachnoid hemorrhage. Treatment strategy should be made by a multi-disciplinary team in accredited centers with proficient experience in both techniques.

关键词： sAH subarachnoid hemorrhage coiling clipping ruptured aneurysm timing intracranial

The new Caribbean Nitrogen Index to assess nitrogen dynamics in vegetable production systems in southwestern Puerto Rico

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International Soil and Water Conservation Research 2017年第1期5卷 69-75页

作者： Miguel Oliveras-Berrocales David Sotomayor-Ramirez jorge A.Delgado Luis R.perez-Alegriad USDA-NRCS Arkansas:2603 Federal Building100 E8th AvePine BluffAR 71601USA University of Puerto Rico Mayaguez CampusCollege of Agricultural SciencesDepartment of Agroenvironmental SciencesPO Box 9000MayagüezPR 00680USA USDA-ARS Acting Research LeaderSoil Management and Sugar Beet Research Unit2150 Centre Ave.Building DSuite 100Fort CollinsCO 80526USA University of Puerto Rico Mayaguez CampusCollege of Agricultural SciencesDepartment of Agricultural and Biosystems EngineeringUSA

Nutrient loss from agricultural fields is one of the main factors influencing surface-and ground-water *** fertilizer nitrogen(N)consumption rates in vegetable production systems and horticultural crops in Puerto Rico fluctuate between 112 and 253 kg N/*** nitrogen use efficiency of vegetable crops is low,increasing the potential for nitrogen losses and high residual soil nitrate *** of residual soil N and N losses to the environment can be a difficult *** models such as the USDA-ARS N Index can be used to identify the relative magnitude of varying N-loss pathways and to identify best management *** studies were conducted to quantify residual soil N and crop N removal,and to validate the Nitrogen Index in onion,tropical pumpkin and tomato production systems in the Lajas Valley in southwestern Puerto *** between observed and simulated values were determined to examine the capability of the model for evaluating N *** was good correlation between observed and predicted values for residual soil N(r=0.88)and crop N removal(r=0.99)(p<0.05).In the production systems evaluated,the N volatilization losses ranged from 1 to 4 kg N/ha,the denitrification losses ranged from 18 to 46 kg N/ha,the leaching losses ranged from 155 to 779 kg N/ha,and the residual soil nitrate ranged from 64 to 401 kg N/*** N use efficiency ranged from 15% to 39%.The results obtained showed that the Nitrogen Index tool can be a useful tool for evaluating N transformations in vegetable production systems of Puerto Rico's semi-arid zone.

关键词： Nitrogen index Nitrogen management Residual soil N Crop N removal

A novel and stretchable carbon-nanotube/Ni@TiO_(2):W photocatalytic composite for the complete removal of diclofenac drug from the drinking water

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Journal of Environmental Sciences 2023年第4期126卷 575-589页

作者： Ernesto Valadez-Renteria Rafael perez-Gonzalez Christian Gomez-Solis Luis Armando Diaz-Torres Armando Encinas jorge Oliva Vicente Rodriguez-Gonzalez Consejo Nacional de Ciencia y Tecnología-División de Materiales Avanzados Instituto Potosino de Investigación Científica y TecnológicaSan Luis Potosí78216México División de Ciencias e Ingenierías Universidad de GuanajuatoLeón 37150México Grupo de Espectroscopia de Materiales Avanzados y Nanoestructurados(GEMANA) Centro de Investigaciones enópticaA.C.Lomas Del CampestreLeón 37150México

We present the structural,morphological and photocatalytic properties of stretchable composites made with carbon nanotubes (CNTs),silicon rubber and Ni@TiO_(2):W nanoparticles(TiWNi NPs) with average size of 37±2 *** images showed that the TiWNi NPs decorated the surface of the CNT fibers,which are oriented in a preferential *** NPs presented a mixture of anatase/rutile phases with cubic *** performance of the TiWNi powders and stretchable composites was evaluated for the photocatalytic degradation of diclofenac (DCF) anti-inflammatory drug under ultraviolet-visible *** results revealed that the maximum DCF degradation percentages were 34.6%,91.9%,97.1%,98.5%and 100%for the CNT composite (stretched at 0%),TiWNi powders,CNT+TiWNi(stretched at 0%),CNT+TiWNi (stretched at 50%) and CNT+TiWNi (stretched at 100%),***,stretching the CNT+TiWNi composites was a good strategy to enhance the DCF degradation percentage from 97.1%to 100%,since stretching created additional defects (oxygen vacancies) that acted as electron sink,delaying the electron-hole recombination,and favors the DCF ***/absorbance measurements confirmed the presence of such ***,the reactive oxygen species (ROS) were determined by the scavenger’s experiments and found that the main ROS were the·OH and O_(2)-radicals,which attacked the DCF molecules,causing their *** results of this investigation confirmed that the stretchable CNT/TiWNi-based composites are a viable alternative to remove pharmaceutical contaminants from water and can be manually separated from the decontaminated water,which is unviable using photocatalytic powders.

关键词： Diclofenac Pharmaceutical contaminant TiO_(2) Carbon nanotubes Stretchable composite Photocatalysis

Eucalyptus grandis plantations:effects of management on soil carbon,nutrient contents and yields

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Journal of Forestry Research 2020年第2期31卷 601-611页

作者： Diego Martin Sandoval Lopez Marcelo Fabian Arturi Juan Francisco Goya Carolina Alejandra perez jorge Luis Frangi Laboratorio de Investigacion de Sistemas Ecologicos y Ambientales(LISEA) Universidad Nacional de La PlataDiagonal 113 N°4691900 La PlataBuenos AiresArgentina

The expansion of fast-growing tree plantations is a worldwide process,with consequences on soil fertility and soil carbon *** results were found on the effects of afforestation with Eucalyptus on soil carbon and other nutrient *** discrepancies are usually caused by differences in climate,land use history,soil texture as well as by management related factors such as plantation age,number of rotations,method of establishment(plantation or coppice),harvest residue management and soil *** studied the effect of plantation age,number of rotations,and method of establishment on soils and plant nutrient concentrations in Eucalyptus grandis plantations in NE Argentina on different textured *** also determined if yields changed with nutrient variations in soils,and compared soils under plantations to soils under grasslands they ***-one *** stands of different ages,number of rotations and method of establishment were evaluated as well as eight grassland *** of carbon,nitrogen,phosphorus,potassium,calcium and magnesium were determined for soils and *** carbon and nitrogen decreased over the number of rotations and were more pronounced in soils with 50-60%sand than soils with>75%*** stands showed higher soil carbon and nitrogen levels than plantations,suggesting a negative effect of site preparation before planting on soil nutrient conservation,especially in fine-textured *** nutrient concentrations did not follow the trends observed for soil nutrients nor did they reflect nutrient *** was no evidence of decreased yields over successive *** carbon and nitrogen contents decrease when grasslands are replaced by *** plantations,and therefore a yield limitation may occur in a medium to long-term frame,especially in stands re-established for short-rotation *** residue management and site preparation must be specifically designed for improving so

关键词： Soil texture Grasslands Foliar nutrient concentrations Successive harvest Coppice Eucalyptus grandis

Standardization of Work for Setting the Tone of Ceramics

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Journal of Mechanics Engineering and Automation 2014年第12期4卷 1008-1013页

作者： Jose Victor galaviz Rodriguez Miguel Terrdn Hernandez Vicente Flores Lara jorge Bedolla Hernandez Engineering and Industrial Operations/Industrial Maintenance Engineering Technological University of Tlaxcala Huamantla90500 MOxico Metal-Mechanical Department Apizaco Institute of Technology Apizaco 90300 MOxico

Leading Company in the field of ceramic floor and wall, has different areas of workforce development, in this research, we will focus the tone adjustment area that is committed to the quality of the final product because this depends on the tone and color appearance tile. Since there is a need to standardize the procedure of work in the area pitch adjustment so that the head of the area and adjusters have precise specifications when developing the activities. To standardize the procedure proposed and implemented tools and formats to help in practical ways to the adjuster also raised the activities of the head of the area and the setting of tone and adjusters.

关键词： Tone standardize adjuster specification procedure.

Formation potential and analysis of 32 regulated and unregulated disinfection by-products: Two new simplified methods

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Journal of Environmental Sciences 2022年第7期34卷 209-221页

作者： Jillian N.Murakami Xu Zhang Joanne Ye Amy M.MacDonald jorge perez David W.Kinniburgh Susana Y.Kimura Department of Chemistry University of CalgaryCalgaryAlbertaT2N 1N4Canada Alberta Centre for Toxicology University of CalgaryCalgaryAlbertaT2N 4N1Canada

Water disinfection is an essential process that provides safe water by inactivating pathogens that cause waterborne diseases. However, disinfectants react with organic matter naturally present in water, leading to the formation of disinfection by-products(DBPs). Multi-analyte methods based on mass spectrometry(MS) are preferred to quantify multiple DBP classes at once however, most require extensive sample pre-treatment and significant resources. In this study, two analytical methods were developed for the quantification of 32 regulated and unregulated DBPs. A purge and trap(P&T) coupled with gas chromatography mass spectrometry(GC-MS) method was optimized that automated sample pre-treatment and analyzed volatile and semi-volatile compounds, including trihalomethanes(THMs), iodinated trihalomethanes(I-THMs), haloacetonitriles(HANs), haloketones(HKTs) and halonitromethanes(HNMs). LOQs were between 0.02-0.4 μg/L for most DBPs except for 8 analytes that were in the low μg/L range. A second method with liquid chromatography(LC) tandem mass spectrometry(MS/MS) was developed for the quantification of 10 haloacetic acids(HAAs) with a simple clean-up and direct injection. The LC-MS/MS direct injection method has the lowest detection limits reported(0.2-0.5 μg/L). Both methods have a simple sample pre-treatment, which make it possible for routine analysis. Hyperchlorination and uniform formation conditions(UFC) formation potential tests with chlorine were evaluated with water samples containing high and low TOC. Hyperchlorination formation potential test maximized THMs and HAAs while UFC maximized HANs. Ascorbic acid was found to be an appropriate quencher for both analytical methods. Disinfected drinking water from four water utilities in Alberta, Canada were also evaluated.

关键词： Disinfection byproducts Purge and trap LC-MS/MS Drinking water DBP formation potential HAAs HANs

Possibility of Predicting Category-5 North Atlantic Hurricanes

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Journal of Earth Science and Engineering 2014年第9期4卷 572-579页

作者： jorge perez-Peraza Alan Juarez Zuniga Instituto de Geofisica Universidad Nacional Autonoma de Mexico Coyoacan 04510 Mexico

Category-5 hurricanes are the most devastating from the standpoint of human and economic losses. The occurrence of this kind of hurricane is believed to be of quasi-random nature, so it is very difficult to predict them well in advance. Warnings at this regard are generally given in the course of their development. We propose here, that there are some inherently periodicities of the phenomena that allow to predict category-5 hurricanes, even with some years of anticipation. For our study, we consider the North Atlantic category-5 hurricanes since 1920. We consider in this study data of the SST （sea surface temperature） of the North Atlantic Ocean as a representative parameter of hurricane activity. Then, by means of the wavelet analysis, we determine the dominant oscillation periods and establish correspondence rules using fuzzy logic. The wavelet power spectrum yields the following dominant periodicities： 0.5, 1, 3, 11, 22 and 32 years. The fuzzy logic searches for associations between the hurricanes occurrence and the behavior of the harmonics. Such correspondence rules lead us to restrict dates of possible hurricane occurrence. Interpolation of the periodic behavior allows for a good reconstruction of past hurricanes dates since 1920, as well as extrapolation to predict dates of occurrence in the future. We conclude that the conditions for the formation of the next category-5 hurricane in the North Atlantic may occur during the seasons of 2015-2017 with the highest probability in 2017.

关键词： North Atlantic Hurricane Predictions.

Progress in Use of Natural Products and Their Active Components against Helicobacter pylori

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Advances in Microbiology 2016年第14期6卷 1091-1129页

作者： Alejandro Venegas jorge Hantar Touma Jessica Bravo Guillermo perez-perez Centro de Investigación Biomédica Facultad de Medicina Universidad Diego Portales Santiago Chile Departments of Medicine and Microbiology New York Langone Medical Center NYU New York USA

Helicobacter pylori is considered the main etiological agent of gastritis, ulcers, and gastric carcinoma. It colonizes human gastric mucosa quite efficiently. Fifty % of the world population is actually infected. Since H. pylori discovery in 1982, it is well known the sensitivity of several H. pylori strains to a number of antibiotics when these are assayed in vitro. However, eradication therapies with a single antibacterial agent have failed. Recently, triple, quadruple, sequential, concomitant and hybrid therapies which include antibiotics and a proton pump inhibitor show improved eradication rate and low side effects. However, new problems have emerged. Antimicrobial resistance to the common antibiotics used has become a problem in both developed and developing countries. In particular, H. pylori clarithromycin- and metronidazole-resistant strains are a major problem in countries where H. pylori is highly prevalent. Thus, the widespread use of antibiotics is not economically feasible and might increase difficulties in the treatment of H. pylori. At present, there are no vaccines available in the market. As an alternative, effective non-antibiotic compounds should be highly desirable since their use may be safer and suitable to eradicate H. pylori. The first step in this direction has been to study the effect of medicinal herbs and natural products, such as green tea, ginseng, garlic, propolis, and probiotics, then identify their active components such as polyphenols, antioxidants, purify them, and finally test them using in vitro and in vivo H. pylori growth assays. Some of them have been quite effective. The topics related to alternative therapies for H. pylori infections and current status of their use will be discussed in the present review.

关键词： H. pylori Growth Inhibition Natural Products Herb Infusions Phytochemicals