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Characterization and Pyrometallurgical Removal of Arsenic from Copper Concentrate Roasting Dust

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Journal of Minerals and Materials Characterization and Engineering 2021年第6期9卷 609-620页

作者： Hector Henao Ignacio Paredes Rodrigo Diaz javier ortiz Metallurgy Engineering Department Technical University Federico Santa María Valparaíso Chile CODELCO Ministro Hales Division Antofagasta Chile

This paper describes the experimental results of removing arsenic from the dust collected in electrostatic precipitators of a fluidized bed roasting furnace (RP dust). The fluidized bed roasting process generates 600 kilotons of copper concentrate per year with 3 - 6 wt% of concentration of arsenic, producing a roasted product with a low content of arsenic below 0.3 wt%. The process generates 27 kilotons of RP dust per year with a concentration of arsenic of the order of 5 wt% and copper concentration of around 20 wt%. Subsequently, the dust collected in the electrostatic precipitators is treated by hydrometallurgical methods allowing the recovery of copper, and the disposition of arsenic as scorodite. This work proposes to use a pyrometallurgy process to the volatilization of arsenic from RP dust. The obtained material can be recirculated in copper smelting furnaces allowing the recovery of valuable metals. The set of experiments carried out in the roasting of the mixture of copper concentrate/RP dust and sulfur/RP dust used different ratios of mixtures, temperatures and roasting times. By different techniques, the characterization of the RP dust determined its size distribution, morphology, and chemical and mineralogical composition. RP dust is a composite material of small particles (<5 μm) in 50 μm agglomerates, mostly amorphous, with a complex chemical composition of sulfoxides. The results of the roasting experiments indicated that for a 75/25 weight ratio of the mixture of the copper concentrate/PR dust under 700℃, 15 minutes of roasting time with injection of air, the volatilization of arsenic reached 96% by weight. The arsenic concentration after the roasting process is less than 0.3% by weight. For a 5/95 mixture of sulfur/RP dust, at 650℃, the volatilization of arsenic reached a promissory result of 67%. Even that this study was carried out for a particular operation, the results have the potential to be extended to dust produced in the roasting of concen

关键词： Copper Smelter Dust Electrostatic Precipitators of Copper Removal of Arsenic Sulfidation Roasting Process Fluidized Bed Roasting

Pyrometallurgical Removal of Arsenic from Electrostatic Precipitators Dusts of Copper Smelting

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Journal of Minerals and Materials Characterization and Engineering 2021年第6期9卷 545-565页

作者： Hector Henao Ignacio Paredes Rodrigo Diaz javier ortiz Metallurgy Engineering Department Technical University Federico Santa María Av. Espa&#241 a 1680 Postal Code 2340000 Valparaíso Chile CODELCO Ministro Hales Division 48739 Antofagasta Chile

This work describes the experimental results of pyrometallurgical removing of arsenic from the dust collected in the electrostatic copper precipitators within the gas cleaning system of a Copper Flash Smelting Furnace. The generation of dust in the copper smelting worldwide ranges from 2 - 15 wt% per ton of a copper concentrate. In Chile, copper smelters produce approximately 110 kt/y of dust with a concentration of arsenic between 1 and 15 wt%. The dust is a complex of metals oxides and sulfurs with copper concentrations greater than 10 wt% and relatively high silver concentrations. Since its high arsenic concentration, it is difficult to recover valuable metals through hydrometallurgical processes or by direct recirculation of the dust in a smelting furnace. Thus, the development of pyrometallurgical processes aimed at reducing the concentration of arsenic in the dust (<0.5 wt%) is the main objective of this study, giving particular attention to the production of a suitable material to be recirculated in operations of copper smelting. The work provides a detailed characterization of the dust including the Quantitative Evaluation of Minerals by Scanning Electron Microscopy (QEMSCAN), Scanning Electron Microscope-Energy Dispersive X-ray Analysis (SEM/EDS), X-Ray Diffraction (XRD), the elemental chemical analysis using Atomic Adsorption (AAS), and X-Ray Fluorescence (X-RF). By considering that arsenic volatilization requires a process of sulfidation-decomposition-oxidation, this work seeks to explore the roasting of mixtures of copper concentrate/dust, sulfur/dust, and pyrrhotite/dust. By the elemental chemical analysis of the mixture after and before the roasting process, the degree of arsenic volatilization was determined. The results indicated the effects of parameters such as roasting temperature, gas flow, gas composition, and the ratio of mixtures (concentrate/dust, sulfur/dust, or pyrrhotite/dust) on the volatilization of arsenic. According to the findings, th

关键词： Copper Smelter Dust Electrostatic Precipitators of Copper Removal of Arsenic Sulfidation Roasting Process

Identification and heterologous expression of the globomycin biosynthetic gene cluster

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Synthetic and Systems Biotechnology 2023年第2期8卷 206-212页

作者： Daniel Oves-Costales Tetiana Gren Eva Baggesgaard Sterndorff Jesús Martín Francisco javier ortiz-Lopez Tue S.Jørgensen Xinglin Jiang Fernando Roman-Hurtado Fernando Reyes Olga Genilloud Tilmann Weber Fundacion MEDINA Centro de Excelencia en Investigaci´on de Medicamentos Innovadores en AndalucíaAvda del Conocimiento 3418016ArmillaGranadaSpain The Novo Nordisk Foundation Center for Biosustainability Technical University of DenmarkKemitorvetbuilding 2202800 Kgs.LyngbyDenmark

Globomycin is a cyclic lipodepsipeptide originally isolated from several Streptomyces species which displays strong and selective antibacterial activity against Gram-negative *** mode of action is based on the competitive inhibition of the lipoprotein signal peptidase II(LspA),which is absent in eukaryotes and considered an attractive target for the development of new *** its interesting biological properties,the gene cluster encoding its biosynthesis has not yet been *** this study we employed a genome-mining approach in the globomycin-producing Streptomyces ***-278952 to identify a candidate gene cluster responsible for its biosynthesis.A null mutant was constructed using CRISPR base editing where production was abolished,strongly suggesting its involvement in the *** putative gene cluster was then cloned and heterologously expressed in Streptomyces albus J1074 and Streptomyces coelicolor M1146,therefore unambigu-ously linking globomycin and its biosynthetic gene *** work paves the way for the biosynthesis of new globomycin derivatives with improved pharmacological properties.

关键词： Globomycin Signal peptidase II Cyclic lipodepsipeptide Genome mining CRISPR-cBEST Heterologous expression

Genomics-driven discovery of pneumocandin biosynthetic gene cluster in the fungus Glarea lozoyensis

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Genomics-driven discovery of pneumocandin biosynthetic gene ...

Origin of nucleation and growth of extension twins in grains unsuitably oriented for twinning during deformation of Mg-1%Al

2012年中国菌物学会学术年会

作者： javier ortiz-López Gerald F.Bills Zhiqaing An Fundación MEDINA Centro de Excelencia en Investigación de Medicamentos Innovadores en AndaluciaGranadaSpain Brown Foundation Institute of Molecular Medicine University of Texas Health Science Center at HoustonHoustonTX 77030USA

The antifungal caspofungin is a semi-synthetic derivative of the lipohexapetide pneumocandin B produced by the fungus Glarea lozoyensis.A whole genome sequencing approach has identified the pneumocandin biosynthetic gene cluster which contains a nonribosomal peptide synthetase(NRPS,GLNRPS4),a polyketide synthase(PKS,GLPKS4),and at least nine other modifying *** mutants of GLNRPS4 or GLPKS4 no longer produce pneumocandin and lose their antibiotic activity against Candida *** additional to pneumocandins,the *** genome reveals a rich repertoire of natural product-encoding gene clusters which include 24 PKSs,6 NRPSs,5 PKS-NRPS hybrids,2 dimethylallyltryptophan synthases,and 3 terpene *** of the gene cluster provides a blueprint for bioengineering novel pneumocandin derivatives with more desirable pharmacological properties such as oral *** genome estimation of secondary metabolite-encoding genes from *** illustrates the huge potential for natural products drug discovery from the vast fungal kingdom.

关键词： Caspofungin pneumocandin Glarea lozoyensis genome gene cluster

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Journal of Magnesium and Alloys 2024年第3期12卷 1186-1203页

作者： Biaobiao Yang javier LLorca IMDEA Materials Institute C/Eric Kandel 2GetafeMadrid 28906Spain Department of Materials Science Polytechnic University of Madrid/Universidad Politécnica de MadridE.T.S.de Ingenieros de CaminosMadrid 28040Spain

A large number of anomalous extension twins,with low or even negative twinning Schmid factors,were found to nucleate and grow in a strongly textured Mg-1Al alloy during tensile deformation along the extruded *** deformation mechanisms responsible for this behaviour were investigated through in-situ electron back-scattered diffraction,grain reference orientation deviation,and slip trace-modified lattice *** was found that anomalous extension twins nucleated mainly at the onset of plastic deformation at or near grain boundary triple *** were associated with the severe strain incompatibility between neighbour grains as a result from the differentbasal slip-induced lattice ***,the anomalous twins were able to grow with the applied strain due to the continuous activation ofbasal slip in different neighbour grains,which enhanced the strain *** results reveal the complexity of the deformation mechanisms in Mg alloys at the local level when deformed along hard orientations.

关键词： Magnesium Extension twinning In-situ electron back-scattered diffraction basal slip Deformation mechanisms.

Discovery of gargantulides B and C,new 52-membered macrolactones from Amycolatopsis *** absolute stereochemistry of the gargantulide family

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Organic Chemistry Frontiers 2022年第2期9卷 462-470页

作者： Daniel Carretero-Molina Francisco javier ortiz-López Tetiana Gren Daniel Oves-Costales Jesús Martín Fernando Román-Hurtado Tue Sparholt Jorgensen Mercedes de la Cruz Caridad Díaz Francisca Vicente Kai Blin Fernando Reyes Tilmann Weber Olga Genilloud Fundación MEDINA Centro de Excelencia en Investigación de Medicamentos Innovadores en AndalucíaAvda.del Conocimiento 3418016 ArmillaGranadaSpain The Novo Nordisk Foundation Center for Biosustainability Technical University of DenmarkKemitorvetbuilding 2202800 Kgs.LyngbyDenmark

Gargantulides B and C,two new and highly complex 52-membered glycosylated macrolactones,were isolated from Amycolatopsis *** CA-230715 during an antibacterial screening *** structures of these giant macrolides were elucidated by 2D NMR spectroscopy and shown to be related to gargantulide A,although containing additional β-glucopyranose and/orα-arabinofuranose monosaccharides separately attached to their *** sequencing allowed the identification of a strikingly large 216 kbp biosynthetic gene cluster,among the largest type Ⅰ PKS clusters described so far,and the proposal of a previously unreported biosynthetic pathway for gargantulides *** absolute configurations of gargantulides B and C were assigned based on a combination of NMR and bioinformatics analysis of ketoreductase and enoylreductase domains within the multimodular type Ⅰ *** addition,the absolute stereochemistry of gargantulide A has now been revised and *** B and C display potent antibacterial activity against a set of drug-resistant Gram-positive bacteria and moderate activity against the clinically relevant Gram-negative pathogen Acinetobacter baumannii.

关键词： absolute membered backbone

Clival Salivary Heterotopia (Salivary Choristoma): A Rare Radiopathogical Lesión

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Open Journal of Pathology 2022年第4期12卷 115-119页

作者： javier ortiz Juan Carlos Paniagua Luis Chinchilla Enrique Montero Elisa Muñoz María Dolores Ludeña Dpto. de Biología Celular y Patología (Universidad de Salamanca) Servicio de Anatomía Patológica (Hospital Universitario de Salamanca) Salamanca Spain Servicio de Radiodiagnóstico (Hospital Universitario de Salamanca) Salamanca Spain

Objective: To describe the radiological and pathological presentation of a salivary heterotopia in clivus. The lesion was detected incidentally in a 57-year-old woman. Material and Methods: Radiologic imaging (CT scan and MRI) and histological picture obtained from a clival lesion. Results: Radiologically the lesion presented as a well-limited lytic lesion with a diameter of 1.5 cm and accompanied by a cerebrospinal fluid secondary fistula. Histological examination revealed non-pathological salivary gland tissue. Conclusion: The differential diagnosis of this rare entity mandates a histological examination of the lesion.

关键词： Salivary Heterotopia Clivus

Myxoid Meningioma:An Example of a Rare Brain Tumour of Difficult Diagnosis

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Open Journal of Pathology 2013年第1期3卷 51-53页

作者： javier ortiz Maria Dolores Ludena Jesus Goncalves Sofia Del Carmen Angel Maillo Agustin Bullon Pathology Department Hospital Universitario de Salamanca(Complejo Hospitalario de Salamanca)SalamancaSpain Neuro-surgery Department Hospital Virgen de la Vega(Complejo Hospitalario de Salamanca)SalamancaSpain

We present a case of a Myxoid Meningioma noticed in a 43-year-old woman. The patient, who had no noteworthy medical antecedents, showed repeated focal epileptic crisis. Imaging studies (MR and CT) showed a solitary and well delimited tumour located in the frontral lobe. Once extirpated, the histological study revealed a neoplasm of myxoid and benign appearance, with elongated and uniform cells, with no atypias and a very low mitotic index. Immunohistochemisty studies (positivity for Vimentin and Epithelial Membrane Antigen, and negativity for the other markers) as well as physical and radiological examination of the patient (absence of tumours in any other location), suggested the diagnosis of a Myxoid Meningioma, which was confirmed by electron microscopy (by the presence of desmosomes). We also revise the characteristics of Myxoid Meningiomas, an absolutely exceptional primary tumour of the central nervous system.

关键词： Myxoid Meningioma Immunohistochemistry Electron Microscopy

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过早逝去的生命枪支暴力阴影下的美国年轻人

南风窗 2012年第17期 53-57页

作者： Carlos javier ortiz 钟智

造成12人死亡59人受伤的丹佛影院枪击案刚过两周,8月5日,美国威斯康星州奥克利克锡克教寺庙又发生枪击事件,造成7人死亡,4人受伤,半月全美两度宣布下半旗致哀。枪支泛滥造成的暴力犯罪就像一场无声的战争在美国本土进行,虽从未宣战,却... 详细信息

造成12人死亡59人受伤的丹佛影院枪击案刚过两周,8月5日,美国威斯康星州奥克利克锡克教寺庙又发生枪击事件,造成7人死亡,4人受伤,半月全美两度宣布下半旗致哀。枪支泛滥造成的暴力犯罪就像一场无声的战争在美国本土进行,虽从未宣战,却真实而残酷地夺去越来越多人的生命。据2011年1月9日美国《外交政策》披露,美国每年3万多人死于枪支暴力,20万人因枪支暴力受伤。人们因而人心惶惶,更多人选择购买枪支以确保人身安全。目前,美国有2.8亿支枪,32%的家庭拥有枪支。然而,一直在全球范围宣扬自由民主、致力反恐的美国政府却始终未提出任何枪支管制的新举措。

关键词：枪支暴力美国美利坚合众国北美洲芝加哥生命年轻人