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Effect of copper, sulfur, arsenic and antimony on silver distribution in phases of lead blast furnace

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Transactions of Nonferrous Metals Society of China 2014年第4期24卷 1202-1209页

作者： J.CHAIDEZ-FELIX A.rOMErO-SErrANO A.HErNANDEZ-rAMIrEZ M.perez-LABrA I.ALMAGUEr-GUZMAN r.benavides-perez M.FLOrES-FAVELA Metallurgy and Materials Department IPN-ESIQIE UPALMZacatenco Academic Area of Earth Science and Materials UAEH Col. CarbonerasMineral de la Reforma Servicios Administrativos Peoles S.A de C.V. Prol. Comonfort Sur 2050 Col. L. Echeverria

An experimental study was carried out to estimate the effect of the lead impurities on the silver distribution in the phases formed in the lead blast furnace. Samples of sinter with different contents of Cu, S, As and Sb were equilibrated under reducing atmosphere （p（CO）/p（CO2）=2.45） at 1573 K in a tube furnace and slowly cooled. The samples were characterized by scanning electron microscopy and microanalysis （SEM-EDS）. There were five immiscible phases：slag （CaO, FeO and SiO2）, matte （S, Cu and Fe）, speiss （As, Fe and Cu）, Cu-Sb phase and lead bullion （Pb, Ag, Sb, Cu, etc）. The results showed that Cu and Sb promote silver losses during the process since they form a liquid solution with higher silver solubility than liquid bullion. Sulfur and arsenic react with copper to form the matte and speiss phases, respectively. The effect of S and As is to reduce the amount of Cu-Sb alloy and then the silver losses from the bullion.

关键词： lead blast furnace silver lead impurities

L^1→L^q Poincare Inequalities for 0representation Formulas

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Acta Mathematica Sinica,English Series 2002年第1期18卷 1-20页

作者： perez Carlos Departamento dr Matematicas. Universidad Autónoma de Madrid. 28049 Madrid. Spain

Civen two doubling measures μ and v in a metric apace (S.p)of homogeneous type. let B_0 S be a given ball. It has been a well-known result bv now (see)[1 4])theat the validity of an L^1→L^1 Poincaré inequality of the following form: f_B|f-f_B|dv≤cr(B)f_Bgdμ. for all metric balls B B_0 S, implies a variant of representation formula of fractonal integral type: |f(x)-f_(B(11))|≤C integral from n=B_(11) g(y)p(x, y)/μ(B(x, p(x, y)))dμ(y)+C(r(B_0))/(μ(B_0))integral from n=B_0 g(y)dμ(y). One of the main results of this paper shows that an L^1 to L^q Poincaré inequality for some 01, i.e.. (f_B|f-f_B|~q dv)^(1/q)≤cr(B) f_B gdμ, for all metric balls B B_0. will suffice to imply the above representation formula. As an immediate corollary, we can show that the weak-type condition. sup_(λ>0)(λv({x ∈ B:|f(x)-f_B|>λ}))/v(B)≤Gr (B)f_B gdμ. also implies the same formula. Analogous theorems related to high-order Poincaréinequalities and Sobolev spaces in metric spaces are also proved.

关键词： Sobolev spaces representation formulas High-order derivatives Vector fields Metric spaces Polynomials Doubling measures Poincare inequalities

Metabolomics-assisted refinement of the pathways of steroidal glycoalkaloid biosynthesis in the tomato clade

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Journal of Integrative Plant Biology 2014年第9期56卷 864-875页

作者： Kevin Schwahn Leonardo perez de Souza Alisdair r.Fernie Takayuki Tohge University of Potsdam AG BioinformaticsInstitute for Biochemistry and Biology MaxPlanck-Institute of Molecular Plant Physiology

Steroidal glycoalkaloids（SGAs） are nitrogen-containing secondary metabolites of the Solanum species,which are known to have large chemical and bioactive diversity in *** recent effort and development on LC/MS techniques for SGA profiling have elucidated the main pathways of SGA metabolism in tomato,the problem of peak annotation still remains due to the vast diversity of chemical structure and similar on overlapping of chemical *** we provide a case study of peak classification and annotation approach by integration of species and tissue specificities of SGA accumulation for provision of comprehensive pathways of SGA *** order to elucidate natural diversity of SGA biosynthesis,a total of 169 putative SGAs found in eight tomato accessions（Soianum lycopersicum, ***, ***, ***, ***,***,***,***） and four tissue types were used for correlation *** results obtained in this study contribute annotation and classification of SGAs as well as detecting putative novel biosynthetic branch *** such this represents a novel strategy for peak annotation for plant secondary metabolites.

关键词： Fruit ripening glycoalkaloids secondary metabolite Solanum lycopersicum tomato accessions

role of dup A in virulence of Helicobacter pylori

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World Journal of Gastroenterology 2016年第46期22卷 10118-10123页

作者： Amin Talebi Bezmin Abadi Guillermo perez-perez Department of Bacteriology Faculty of Medical Sciences Tarbiat Modares University Departments of Medicine and Microbiology New York University School of Medicine and VA Medical Center

Helicobacter pylori(H. pylori) is a gastric human pathogen associated with acute and chronic gastritis, 70% of all gastric ulcers, 85% of all duodenal ulcers, and both forms of stomach cancer, mucosal-associated lymphoid tissue(MALT) lymphoma and adenocarcinoma. recently, attention has focused on possible relationship between presence of certain virulence factor and H. pylori-associated diseases. Some contradictory data between this bacterium and related disorders has been observed since not all the colonized individuals develop to severe disease. The reported diseases plausibility related to H. pylori specific virulence factors became an interesting story about this organism. Although a number of putative virulence factors have been identified including cytotoxin-associated gene a(cag A) and vac A, there are conflicting data about their actual participation as specific risk factor for H. pylori-related diseases. Duodenal ulcer promoting gene a(dup A) is a virulence factor of H. pylori that is highly associated with duodenal ulcer development and reduced risk of gastric cancer. The prevalence of dup A in H. pylori strains isolated from western countries is relatively higher than in H. pylori strains from Asian countries. Current confusing epidemiological reports will continue unless future sophisticated and molecular studies provide data on functional and complete dup A cluster in H. pylori infected individuals. This paper elucidates available knowledge concerning role of dup A in virulence of H. pylori after a decade of its discovery.

关键词： Helicobacter pylori dup A Bacterial virulence infection Clinical outcome

The Finite-dimensional Decomposition Property in Non-Archimedean Banach Spaces

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Acta Mathematica Sinica,English Series 2014年第11期30卷 1833-1845页

作者： Albert KUBZDELA Cristina perez-GArCIA Institute of Civil Engineering Poznań University of TechnologyUl.Piotrowo 561-138 PoznańPoland Department of Mathematics Facultad de CienciasUniversidad de CantabriaAvda.de los Castros s/n39071SantanderSpain

A non-Archimedean Banach space has the orthogonal finite-dimensional decomposition property（OFDDP） if it is the orthogonal direct sum of a sequence of finite-dimensional *** property has an influence in the non-Archimedean Grothendieck＇s approximation theory,where an open problem is the following： Let E be a non-Archimedean Banach space of countable type with the OFDDP and let D be a closed subspace of *** D have the OFDDP？ In this paper we give a negative answer to this question; we construct a Banach space of countable type with the OFDDP having a one-codimensional subspace without the *** we prove that,however,for certain classes of Banach spaces of countable type,the OFDDP is preserved by taking finite-codimensional subspaces.

关键词： Non-Archimedean Banach spaces finite-dimensional decomposition property orthogonal base

Implementing a vector surveillanceresponse system for chagas disease control:a 4-year field trial in Nicaragua

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Infectious Diseases of Poverty 2017年第1期6卷 154-165页

作者： Kota Yoshioka Doribel Tercero Byron perez Jiro Nakamura Lenin perez Doctor of Public Health Program Harvard T.H.Chan School of Public HealthBostonUSA School of Tropical Medicine and Global Health Nagasaki UniversityNagasakiJapan Former Chagas Disease Control Project Japan International Cooperation AgencyManaguaNicaragua Department of Disease Prevention Ministry of Health in NicaraguaManaguaNicaragua

Background:Chagas disease is one of the neglected tropical diseases(NTDs).International goals for its control involve elimination of vector-borne *** American countries face challenges in establishing sustainable vector control programmes,since the main vector,Triatoma dimidiata,cannot be *** 2012,the Ministry of Health in Nicaragua started a field test of a vector surveillance-response system to control domestic vector *** paper reports the main findings from this pilot ***:This study was carried out from 2012 to 2015 in the Municipality of *** Japan International Cooperation Agency provided technical cooperation in designing and monitoring the surveillance-response system until *** system involved 1)vector reports by householders to health facilities,2)data analysis and planning of responses at the municipal health centre and 3)house visits or insecticide spraying by health personnel as a *** registered all vector reports and responses in a digital *** collected data were used to describe and analyse the system performance in terms of amount of vector reports as well as rates and timeliness of ***:During the study period,*** was reported 396 *** analysis identified some high-risk *** houses reported to be infested were visited by health personnel in 2013 and this response rate dropped to 39%in *** of insecticide spraying rose above 80%in 2013 but no spraying was carried out in the following 2 *** timeliness of house visits improved significantly after the responsibility was transferred from a vector control technician to primary health care ***:We argue that the proposed vector surveillance-response system is workable within the resourceconstrained health system in *** to the primary health care services was a key to improve the system *** efforts are necessary to keep adap

关键词： Chagas disease Triatoma dimidiata Vector control Surveillance-response system Programme integration Nicaragua

Infuence of elemental composition in environmental impacts of steel

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Journal of Iron and Steel research International 2020年第5期27卷 598-607页

作者： E.Batuecas C.Mayo r.Diaz F.J.perez Thermal and Fluid Engineering Department Carlos III University of Madrid28911 LeganesMadridSpain Chemical and Materials Engineering Department Complutense University of Madrid28040 MadridSpain Technical Sciences and Engineering UDIMA University28400 Collado VillalbaMadridSpain。

The environmental behavior of four steels was *** the operation phase of concentrating solar power plants,steels withstand high temperature because of its contact with molten ***,choosing the steel type for the molten salt tanks remains a great *** the cold tank,carbon steel is usually used although an approach with low chromium content steel is being studied for these ***,in high temperature applications,such as hot store tank,austenitic stainless steel is the most frequent ***,ferritic steel is being considered as a promising material in these *** many researchers studied the steel technical properties without considering their environmental damages,this work aimed to introduce the environmental aspects into the material choice by using the life cycle assessment *** one hand,the results showed the environmental adequacy of carbon steel against low chromium content *** the other hand,the results obtained in those steels suitable in high temperature application revealed signifcant environmental benefts from the ferritic steel instead of the austenitic steel.

关键词： renewable energy Concentrating solar power Life cycle assessment Molten salt Ferritic steel Austenitic steel

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)(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

In vitro germination and shoot proliferation of the threatened species Cinchona officinalis L(rubiaceae).

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Journal of Forestry research 2016年第6期27卷 1229-1236页

作者： rosa Armijos-Gonzalez Cesar perez-ruiz Departamento de Ciencias Naturales Universidad Tecnica Particular de LojaCP 1101 608 LojaEcuador Departamento de Biotecnologia y Biologia Vegetal E.T.S.Ingenieros AgronomosUniversidad Politecnica de MadridCP 728040 MadridSpain

Cinchona officinalis （rubiaceae） is an endemic species of the Loja Valley in southern Ecuador with medicinal uses. Because of over-exploitation in the nine- teenth century and more recent disturbances to its ecosystem, C. officinalis populations are threatened. Currently, natural regeneration of the populations is low, despite its high plant regeneration and seed formation capacity. In the present study, an efficient protocol for germination, shoot proliferation and plantlets regeneration was developed for this species. Phenolic content and germination rate of C. officinalis seeds were compared with a control species, C. pubescens. Nodal segments from seedlings of C. officinalis were cultured on Gamborg medium supplemented with different combinations of plant growth regulators. Because the phenol content is high in C. officinalis, the phenolic should be removed with hydrogen peroxide or water washes to stimulate germination. Shoots and callus developed from nodal segments within 45 days using most of the tested combinations of plant growth regulators. The best rates of shoot proliferation, callus formation and adventitious buds were obtained in medium supplemented with 5.0 mg L^-1 6-benzyl-aminopurine and 3.0 mg L^-1 indole- 3-butyfic acid.

关键词： Callus Cinchona officinalis Germination Phenols rubiaceae Shoot