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Copper and Cyanide Recovery in Cyanidation Effluents

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Advances in Chemical Engineering and Science 2011年第4期1卷 191-197页

作者： José R. Parga Jesús L. valenzuela Héctor Moreno Jaime E. Pérez 不详

Cyanidation is the main process for gold and silver recovery from its ores. In this study, a process is proposed to recover copper and cyanide from barren solutions from the Merrill-Crowe cementation process with zinc dust. This technology is based on inducing nucleated precipitation of copper and silver in a serpentine reactor, using sodium sulfide as the precipitator, and sulfuric acid for pH control. Results show that pH value has a significant effect on copper cyanide removal efficiency, and it was determined the optimal pH range to be 2.5 - 3. At this pH value, the copper cyanide removal efficiency achieved was up to 97 and 99%, when copper concentration in the influent was 636 and 900 ppm. respectively. In this process (sulphidization-acidification-thickening-HCN recycling), the cyanide associated with copper cyanide complexes, is released as HCN gas under weakly acidic conditions, allowing it to be recycled back to the cyanidation process as free cyanide. Cyanide recovery was 90%. Finally, this procedure was successfully run at Minera William in México.

关键词： Precipitation Cyanide Removal Copper Recovery Cyanidation

Solid Particle Erosion of AISI 304 SS Caused by Alumina Particles

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Journal of Surface Engineered Materials and Advanced Technology 2024年第1期14卷 1-14页

作者： Juan Rodrigo Laguna-Camacho Celia María Calderón-Ramón víctor velázquez-Martínez Javier Calderón-Sánchez Gabriel Juárez-Morales Cristóbal Cortez-Domínguez Jorge Alberto Chagoya-Ramírez Jesús Enrique López-Calderón Paul Ramírez-Sánchez Silvia Marina Sánchez-Yáñez Héctor Daniel López-Calderón Faculty of Electrical and Mechanical Engineering Universidad Veracruzana Poza Rica Veracruz Mexico Facultad de Ciencias Biolgicas y Agropecuarias Universidad Veracruzana Tuxpan Veracruz Mexico Facultad de Biologa Universidad Veracruzana Xalapa Veracruz Mexico

This research work was carried out with the aim of continuing to expand knowledge on the behaviour of AISI 304 stainless steel against solid particle erosion. In this particular case, the steel was subjected to the impact of alumina particles, which are hard abrasives with irregular and angular shapes. Different characterization techniques were applied to gain a better understanding of alumina. For instance, particle size distribution was obtained using the Analysette 28 Image Sizer and the particle size was between 300 - 400 µm. SEM and EDS analysis were used to know the morphology and chemical composition of both the abrasive particles and AISI 304 stainless steel. Additionally, mechanical properties values such as the hardness and Young’s modulus of AISI 304 steel were attained using a Berkovich indenter (model TTX-NHT, CSM Instruments). On the other hand, two tests were carried out for each impact angle used, 30˚, 45˚, 60˚ and 90˚, with a particle velocity of 24 ± 2 m/s and an abrasive flow rate of 63 ± 0.5 g/min, employing a test rig based on ASTM G76-95 standard. SEM images using two detectors, Backscattered Electron Detector (BED) and Low Electron Detector (LED), were employed to identify the wear mechanisms on the AISI 304 eroded surfaces at 30˚ and 90˚. Finally, the erosion rates of AISI 304 compared to those results reached by AISI 1018 steel and AISI 420 stainless steel tested under identical conditions in previous works.

关键词： Solid Particle Erosion AISI 304 Stainless Steel Alumina Particles Wear Mechanisms Erosion Rates

Isolated attosecond pulse generation in a semiinfinite gas cell driven by time-gated phase matching

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Light(Science & Applications) 2024年第10期13卷 2192-2200页

作者： Federico vismarra Marina Fernández-Galán Daniele Mocci Lorenzo Colaizzi víctor Wilfried Segundo Roberto Boyero-García Javier Serrano Enrique Conejero-Jarque Marta Pini Lorenzo Mai Yingxuan Wu Hans Jakob Wörner Elisa Appi Cord LArnold Maurizio Reduzzi Matteo Lucchini Julio San Román Mauro Nisoli Carlos Hernández-García Rocío Borrego-varillas Department of Physics Politecnico di MilanoPiazza Leonardo da Vinci 3220133 MilanoItaly IFN-CNR Piazza Leonardo da Vinci 3220133 MilanoItaly Grupo de Investigación en Aplicaciones del Láser y Fotónica Departamento de Física AplicadaUniversidad de SalamancaE-37008 SalamancaSpain Unidad de Excelencia en Luz y Materia Estructuradas(LUMES) Universidad de SalamancaSalamancaSpain Laboratorium für Physikalische Chemie ETH Zürich8093 ZürichSwitzerland Department of Physics Lund UniversityLundSweden

Isolated attosecond pulse(IAP)generation usually involves the use of short-medium gas cells operated at high *** contrast,long-medium schemes at low pressures are commonly perceived as inherently unsuitable for IAP generation due to the nonlinear phenomena that challenge favourable phase-matching *** we provide clear experimental evidence on the generation of isolated extreme-ultraviolet attosecond pulses in a semiinﬁnite gas cell,demonstrating the use of extended-medium geometries for effective production of *** gain a deeper understanding we develop a simulation method for high-order harmonic generation(HHG),which combines nonlinear propagation with macroscopic HHG solving the 3D time-dependent Schrödinger equation at the singleatom *** simulations reveal that the nonlinear spatio-temporal reshaping of the drivingﬁeld,observed in the experiment as a bright plasma channel,acts as a self-regulating mechanism boosting the phase-matching conditions for the generation of IAPs.

关键词： matching nonlinear ultraviolet

Characterizing proteases in an Antarctic Janthinobacterium sp. isolate: Evidence of a protease horizontal gene transfer event

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Advances in Polar Science 2015年第1期26卷 88-95页

作者： Cecilia Martinez-Rosales Juan José Marizcurrena Andrés Iriarte Natalia Fullana Héctor Musto Susana Castro-Sowinski Sección Bioquímica y Biología Molecular Facultad de Ciencias Universidad de la República (Udela R) Igua 4225 11400 Montevideo Uruguay Microbiología Molecular Instituto de Investigaciones Biológicas Clemente Estable (IIBCE).Av Italia 3318 11600Montevideo Uruguay Dpto de Bioquímica y Genómica Microbiana and Dpto de Genómica (IIBCE) Dpto de Desarrollo Biotecnológico Instituto de Higiene Facultad de Medicina Udela R Laboratorio de Organización y Evolución del Genoma Facultad de Ciencias Udela R

We report the isolation of a cold-adapted bacterium belonging to the genus Janthinobacterium （named AU 11）, from a water sample collected in Lake Uruguay （King George Island, South Shetlands）. AUI 1 （growth between 4℃ and 30℃） produces a single cold-active extracellular protease （ExPAU11）, differentially expressed at low temperature. ExPAU11 was identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-ToF MS） as an alkaline metallo-protease （70% coverage with an extracellular protease of Janthinobacterium sp. PI12）, and by protease-inhibitor screening identified as a serine-protease. To the best of our knowledge this is the first experimental evidence of a cold-active extracellular protease produced by Janthinobacterium. Furthermore, we identified a serine-protease gene （named JSP8A） showing 60% identity （98% query coverage） to subtilisin peptidases belonging to the $8 family （S8A subfamily） of many cyanobacteria. A phylogenetic analysis of the JSP8A protease, along with related bacterial protein sequences, confirms that JSP8A clusters with S8A subtilisin sequences from different cyanobacteria, and is clearly separated from SSA bacterial sequences of other phyla （including its own）. An analysis of the genomic organization around JSP8A suggests that this protease gene was acquired in an event that duplicated a racemase gene involved in transforming L- to D-amino acids. Our results suggest that AU11 probably acquired this subtilisin-like protease gene by horizontal gene transfer （HGT） from a cyanobacterittrn. We discuss the relevance of a bacterial protease-HGT in the Antarctic environment in light of this hypothesis.

关键词： Antarctic cold-active protease horizontal gene transfer Janthinobacterium subtilisin

Optimization and validation of a Method for Heavy Metals Quantification in Soil Samples by Inductively Coupled Plasma Sector Field Mass Spectrometry(ICP-SFMS)

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American Journal of Analytical Chemistry 2013年第10期4卷 9-15页

作者： Héctor Hernández-Mendoza Marcos Mejuto Ana Isabel Cardona Avelino García-Alvarez Rocio Millán Abel Yllera Instituto Nacional de Investigaciones Nucleares Carretera México-TolucaLa Marquesa OcoyoacacMéxico Departamento de Medio Ambiente Centro de Investigaciones EnergéticasMedioambientales y Tecnológicas(CIEMAT)AvdaMadridEspana

In this work, a method for quantification of heavy metals Inductively Coupled Plasma Sector Field Mass Spectrometry (ICP-SFMS) in soil samples of El Bierzo district (Spain) has been optimized and validated. Optimization was carried out for elements: Cr, Mn, Co, Ni, Cu, Zn, Se, As, Cd, Hg, Pb and U. validation of the method was performed with Certified and Standard Reference Materials (CRMs and SRMs);SRM2709, CRM020-051 and CRM050-051. Results obtained under optimized conditions can be summarized as follows: a) the Limits of Detection (LODs) were in the order of sub fg·g-1 for Cr, Mn, Cu, Co, As, Cd, Hg, Pb and U, and few fg·g-1for Ni, Zn and Se;b) precision measurement, in terms of relative standard deviation (RSD), was been below 5%;c) the average recovery of CRM was between 81.3% and 98%. In conclusion, the method offers several advantages: fast, good accuracy, very low values of Limits of Quantification (LOQs) and high sensitivity on measurement of heavy metal.

关键词： Soil Heavy Metal ICP-SFMS

First Report on the Presence of Phyllachora sp. in Corn Crops at Toluca, Estado de Mexico

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American Journal of Plant Sciences 2016年第5期7卷 733-739页

作者： Erika Natalia Ríos-Herrera Laila Pamela Partida-Martínez Yisa María Ochoa-Fuentes Ernesto Cerna-Chávez Francisco Daniel Hernández-Castillo Alberto Flores-Olivas víctor Olalde-Portugal Raúl Rodríguez-Guerra Universidad Autónoma Agraria Antonio Narro Saltillo México Department of Genetic Engineering CINVESTAV Irapuato México Department of Agricultural Parasitology Universidad Autónoma Agraria Antonio Narro Saltillo México Department of Biotechnology and Biochemistry CINVESTAV Irapuato México General Terán INIFAP General Terán Nuevo León México

Symptoms of Tar Spot Complex (TSC) in corn appear in the form of black spots surrounded by a chlorotic halo known as fish-eye. The crop with these symptoms was found at San Pablo Autopan, Estado de Mexico. The stromal region of foliar lesions was cut longitudinally, showing perithecia, asci and ascospores typical of Phyllachora maydis. The results were confirmed by PCR-ITS with ITS 1 and ITS4 initiators, cloned by pJET, before being sequenced and compared against NCBI’s data base. Phyllachora identity was confirmed. This is the first report where TSC pathogen has been detected under conditions that had not been previously reported, for instance, at 2600 meters above the sea level.

关键词： Phyllachora maydis Tar Spot Complex ITS

Low serum levels of ghrelin are associated with gallstone disease

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World Journal of Gastroenterology 2006年第19期12卷 3096-3100页

作者： Nahum Méndez-Sánchez Guadalupe Ponciano-Rodríguez Luisa Bermejo-Martínez Antonio R villa Norberto C Chávez-Tapia Daniel Zamora-valdés Raúl Pichardo-Bahena Blanca Barredo-Prieto Martha H Uribe-Ramos Martha H Ramos Héctor A Baptista-González Misael Uribe Liver Unit Biomedical Research Department Medica Sur Clinic and FoundationMexico CityMexico Faculty of Medicine National Autonomous University of Mexico (UNAM) Mexico CityMexico Clinical Research Department National Institute of Perinatology Mexico CityMexico Clinical Epidemiology Unit National Institute of Medical Sciences and Nutrition Mexico CityMexico

AIM： To explore the role of ghrelin in gallstone disease. METHODS： We carried out a cross-sectional study in 150 subjects, 38 with gallstones （cases） and 112 controls. We also did a real-time PCR-RT study in twenty gallbladder samples each. Body mass index （BNI）, serum insulin, ghrelin, and serum lipids were measured. Logistic regression analyses （univariate and multivariate） were conducted to estimate the probability of gallstone disease associated with serum ghrelin concentrations. RESULTS： Cases were statistically different from controls in gender distribution （P = 0.01）, age （53 vs 44 yr, P = 0.002）, BNI （28 vs 25; P = 0.004）, and glucose （5.26 vs 4.98 mmol/L; P = 0.05）. The prevalence of ghrelin serum levels above the third tercile was lower in subjects without metabolic syndrome （P 〈 0.05）. In a multivariate model, we found a protective effect, when ghrelin values were higher than the median value （OR = 0.27, 95%CI 0.09-0.82, P = 0.02）. Twenty （20%） gallbladder specimens expressed ghrelin mRNA. CONCLUSION： Serum ghrelin concentrations are associated with a protective effect of GD.

关键词： Gallstones Obesity Ghrelin Gallbladder Gastrointestinal hormones

巴塔哥尼亚(阿根廷)海洋与河水中腐植酸组成比较

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腐植酸 2011年第4期 27-36页

作者： María del Carmen Scapini víctor Hugo Conzonno vilma Teresa Balzaretti Alicia Fernandez Cirelli 马莉娜李捷巴塔哥尼亚圣胡安博斯科国立大学自然科学系生态与环境系统科学研究室布宜诺斯艾利斯大学兽医科学系多学科水研究中心广东工业大学环境学院广州510006 青岛理工大学环境学院青岛266033

比较了Engao海湾海水(大西洋)和丘布特河水(阿根廷的巴塔哥尼亚)中腐殖质的结构。这些腐殖质被分离、纯化后,通过元素分析法,核磁共振法(13C和1H谱),红外光谱法,紫外吸收法和荧光法等对其结构特性进行了分析鉴定,并以氮含量、氧含量、... 详细信息

比较了Engao海湾海水(大西洋)和丘布特河水(阿根廷的巴塔哥尼亚)中腐殖质的结构。这些腐殖质被分离、纯化后,通过元素分析法,核磁共振法(13C和1H谱),红外光谱法,紫外吸收法和荧光法等对其结构特性进行了分析鉴定,并以氮含量、氧含量、H/C比、C/N比、红外波段中氮和羧基官能团含量、核磁共振吸收谱线中官能团的斜率系数、250和365nm处的吸收比率(E2/E3)、激发—发射模型和荧光量子产率等指标对二者的相似性进行比较。Engao海湾和丘布特河水中的腐殖质主要由黄腐酸组成。尽管它们具有一定的相似性,都含有较高的直链脂肪碳含量(低芳香烃碳含量),但其差异性也十分显著,二者所含蛋白质和羧酸不同。Engano海湾腐殖质主要来自于水生的植物或动物;丘布特河腐殖质也同样来自于水生动植物,但是也有证据表明它可能来自土壤黄腐酸。

关键词：黄腐酸腐殖质激发-发射模型丘布特河 Engano海湾

圈圈圆圆墨西哥Gelatoscopio冰淇淋店

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室内设计与装修 2017年第7期 14-15页

作者： Héctor Esrawe Ignacio Cadena cheri

Gelatoscopio是一家非常有特色的冰淇淋贩卖店。它坐落于墨西哥城,店铺的设计充满了天马行空的构思。设计灵感来源于对现实生活的浪漫想象,冰冷质感的金属条纹墙面搭配明亮的蓝绿色显得生动而有活力。设计师试图通过这个梦幻般的场景设... 详细信息

Gelatoscopio是一家非常有特色的冰淇淋贩卖店。它坐落于墨西哥城,店铺的设计充满了天马行空的构思。设计灵感来源于对现实生活的浪漫想象,冰冷质感的金属条纹墙面搭配明亮的蓝绿色显得生动而有活力。设计师试图通过这个梦幻般的场景设计来衬托冰淇淋香甜的口味和香气。在这个明亮的小屋内,墙壁上布满了大小不一的圆圈设计。

关键词：浪漫想象场景设计 Gelatoscopio 设计灵感现实生活工程名称竣工时间照明系统