检索结果-南通市图书馆

A proposed Global Boundary Stratotype Section and Point for the base of the Middle Ordovician Series： The Niquivil section, Precordillera of San Juan, Argentina

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

episodes 2006年第1期29卷 1-15页

作者： Guillermo L. Albanesi Marcelo G. Carrera fernando L. Canas Matthew Saltzman CONICeT - Facultad de Ciencias exactas Fisicas y Naturales Universidad Nacional de Córdoba Casilla de Correo 1598 5000 Córdoba Argentina CONICeT- Departamento de Geologfa Universidad Nacional de Rio Cuarto Ruta Nacional 36 km 601 5800 Rio Cuarto Argentina Department of Geological Sciences The Ohio State University Columbus OH 43210 USA.

The Niquivil section, Argentine Precordillera, fulfills most of the requirements for a Global Stratotype Section and Point （GSSP） for the base of the Middle Ordovician Series. It has excellent conodont biostratigraphy in a continuous succession of uniform lithology, is readily accessible, and the critical interval is not tectonically affected. The position of the Lower/Middle Ordovician Series boundary in the Central Precordillera is placed at the middle part of the San Juan Formation, an open-platform carbonate unit. The Niquivil section is proposed as a GSSP for the base of the Middle Ordovician, which is marked by the FAD of the conodont Cooperignathus aranda （Cooper）. It occurs in level NCA, at the upper part of the Oepikodus evae Zone （overlapping uppermost records of O. evae in association with other guide species）; i.e., 100.15 m above the base of the reference section. The auxiliary Pena Sombria section from northern Precordillera records graptolites of the lower （but not lowest） Middle Ordovician in the Isograptus victoriae maximus Zone, few meters above the proposed boundary biohorizon. The range of C. aranda can be correlated with the I. victoriae lunatus Zone up to the lower part of the Undulograptus austrodentatus Zone in diverse sections of the world. C. aranda presents cosmopolitan distribution and occurs in virtually all environments. The proposed GSSP preserves a carbon-isotope record that provides an auxiliary marker of potential global application. Radiometric dating of K-bentonite samples, interbedded with carbonate strata yielding lower records of C. aranda, were recovered from the auxiliary Talacasto section in Central Precordillera （469.8 ±2.3 Ma, U-Pb SHRIMP dating）.

关键词：奥陶纪阿根廷界线层型 GSSP 生物地层学

Y-chromosomal microdeletions and partial deletions of the Azoospermia Factor c(AZFc)region in normozoospermic,severe oligozoospermic and azoospermic men in Sri Lanka

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2006年第1期8卷 39-44页

作者： L.fernando J.Gromoll T.R.Weerasooriya e.Nieschlag M.Simoni Institute of Reproductive Medicine of the University Münster University HospitalD-48129 MünsterGermany Reproductive Biology LaboratoryFaculty of MedicineKarapitiyaGalleSri Lanka Institute of Reproductive Medicine of the University Münster University HospitalD-48129 MünsterGermany Reproductive Biology Laboratory Faculty of MedicineKarapitiyaGalleSri Lanka

Aim： To assess for the first time the occurrence of Y chromosomal microdeletions and partial deletions of the Azoospermia Factor c （AZFc） region in Sri Lankan men and to correlate them with clinical parameters. Methods： In a retrospective study, we analyzed 96 infertile men （78 with non-obstructive azoospermia） and 87 controls with normal spermatogenesis. AZFa, AZFb, AZFc and partial deletions within the AZFc region were analyzed by multiplex polymerase chain reaction （PCR） according to established protocols. Results： No AZFa, AZFb or AZFc deletions were found in the control group. Seven patients in the group of infertile men were found to have deletions as following： one AZFa, two AZFc, two AZFbc and two AZFabc. The relative distribution of these patterns was significantly different compared with that found in the German population. extension analysis confirmed that the deletions occurred according to the current pathogenic model, gr/gr deletions were found to be equally present both in the patients （n = 4） and in the control group （n = 4）. One b2/b3 deletion was found in the patient group. Conclusion： These results suggest that the frequency and pattern of microdeletions of the Y chromosome in Sri Lankan men are similar to those found in other populations and confirm that gr/gr deletions are not sufficient to cause spermatogenetic failure. （Asian J Androl 2006 Jan; 8： 39-44）

关键词： Y chromosome male infertility gr/gr b2/b3 microdeletion normozoospermia azoospermia factor c

Functional data-driven framework for fast forecasting of electrode slurry rheology simulated by molecular dynamics

在线全文

学校读者我要写书评

暂无评论

npj Computational Materials 2022年第1期8卷 1524-1532页

作者： Marc Duquesnoy Teo Lombardo fernando Caro Florent Haudiquez Alain C.Ngandjong Jiahui Xu Hassan Oularbi Alejandro A.Franco Laboratoire de Réactivitéet Chimie des Solides(LRCS) UMR CNRS 7314Universitéde Picardie Jules VerneHub de l’Energie15rue Baudelocque80039AmiensCedexFrance ALISTORe-european Research Institute FR CNRS 3104Hub de l’Energie15rue Baudelocque80039AmiensCedexFrance Reseau sur le Stockage electrochimique de l’energie(RS2e) FR CNRS 3459Hub de l’Energie15rue Baudelocque80039AmiensCedexFrance Institut Universitaire de France 103 Boulevard Saint Michel75005ParisFrance

The computational simulation of the manufacturing process of lithium-ion battery composite electrodes based on mechanistic models allows capturing the influence of manufacturing parameters on electrode ***,ensuring that these properties match with experimental data is typically computationally *** this work,we tackled this costly procedure by proposing a functional data-driven framework,aiming first to retrieve the early numerical values calculated from a molecular dynamics simulation to predict if the observable being calculated is prone to match with our range of experimental values,and in a second step,recover additional values of the ongoing simulation to predict its final *** demonstrated this approach in the context of the calculation of electrode slurries *** report that for various electrode chemistries,the expected mechanistic simulation results can be obtained 11 times faster with respect to the complete simulations,while being accurate with a R^(2)_(score) equals to 0.96.

关键词： properties electrode dynamics

Naïve hepatitis B e antigen-negative chronic hepatitis B patients are at risk of carotid atherosclerosis:A prospective study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2021年第30期27卷 5112-5125页

作者： Mar Riveiro-Barciela Cristina Marcos-Fosch fernando Martinez-Valle Fabrizio Bronte Olimpia Orozco Isidro Sanz-Pérez Daniele Torres Maria-Teresa Salcedo Salvatore Petta Rafael esteban Antonio Craxi Maria Buti Department of Medicine of the UAB Hospital Universitari Vall d’HebronBarcelona 08035Spain Centro de Investigación Biomédica en Red de enfermedades Hepáticas y Digestivas Instituto de Salud Carlos IIIMadrid 28029Spain Systemic Autoimmune Diseases Unit Internal Medicine DepartmentHospital Universitari Vall d'HebronBarcelona 08035Spain Sezione di Gastroenterologia Di.Bi.M.I.SUniversity of PalermoPalermo 90133Italy Pathology Department Hospital Universitari Vall d'HebronBarcelona 08035Spain

BACKGROUND There is an increased risk of atherosclerosis in patients with chronic hepatitis C or human immunodeficiency virus,but there is scarce data on hepatitis B virus *** hypothesis of this study is that hepatitis B virus infection increases the risk of carotid plaques and subclinical atherosclerosis in naïve hepatitis B e antigen(HBeAg)negative *** To assess the rate of carotid plaques and subclinical atherosclerosis in naïve HBeAg negative subjects in comparison with a cohort of healthy *** Prospective case-control collaborative study conducted in two tertiary *** hundred and two subjects prospectively recruited at the outpatient clinic were included from May 2016 to April 2017:201 naïve HBeAg-negative hepatitis B virus-infected[49 chronic hepatitis B(CHB)and 152 inactive carriers(ICs)]and 201 healthy *** and metabolic measures,liver stiffness and carotid Doppler ultrasound were *** atherosclerosis was established on an intima-media thickness increase of≥1.2 mm and/or the presence of carotid *** distributed quantitative variables were compared with the Student t test and those with a non-normal distribution with the Mann-Whitney U *** variables were compared between groups using theχ2 or Fisher exact *** Carotid plaques were found more often in CHB(32.7%)than ICs(17.1%)or controls(18.4%)(P=0.048).Subclinical atherosclerosis was also increased in CHB(40.8%)vsICs(19.1%)or controls(19.4%)(P=0.003).No differences in the risk of atherosclerosis were observed between controls and *** factors independently associated with the presence of carotid plaques were age[odds ratio(OR)1.43,Perosclerosis,age(OR 1.45,Petes(OR 1.13,P=0.028).In the subset of young subjects(ears),carotid plaques(12.5%vs 1.1%,P=0.027)and subclinical atherosclerosis(12.5%vs 2.2%,P=0.058

关键词： Hepatitis B virus Carotid plaques Subclinical atherosclerosis Cardiovascular risk endothelial dysfunction Intima-media thickness

estimation of Urban Green Cover Changes in Colombo Municipal Area over Ten Years Using Remote Sensing Techniques

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Urban and environmental Studies 2022年第4期10卷 95-108页

作者： Karunarathna Atapattu Mudiyanselage Ruwanmali Priyanwada ATAPATTU e.A.Nadeeka M.eDIRISINGHe Sarath P.NISSANKA T.Tamasha fernando Ajith Rohana GUNAWARDeNA Postgraduate Institute of Agriculture Old Galaha Road University of Peradeniya Department of Crop Science Faculty of Agriculture University of Peradeniya Research and Development Central Environmental Authority

Colombo is the commercial capital of Sri Lanka, with a high population, buildings, and ***, it is vital to observe the spatial distribution of vegetation types and changes in the green cover of Colombo city to identify priority areas to improve green cover. This study was carried out to estimate the changes in green cover in Colombo Municipal Area(CMA) and its postal zones over 10 years using remote sensing techniques. The green cover was categorized into trees, shrubs, Play-grounds(PG)/Grasslands, wetlands, rooftops, and Ipomoea cover. Accordingly, total green cover increased up to 26.17% from 22.36% during the period of 2012–2022. During the past decade,except for the PG/Grasslands, all other vegetation types have been reduced. Five of the 15 postal zones in the CMA’s green cover have decreased during the past 10 years, including Colombo 04, 05,06, 09, and 13. The highest green cover was recorded in Colombo 07, while the lowest green cover was present in Colombo 11. The outcome of the study emphasizes that CMA is moving towards greening and sustainability even with the expansion of built-up areas and urban populations.

关键词： Urban areas Colombo Municipal Area postal zone green cover remote sensing

Kinetic approach to the study of froth flotation applied to a lepidolite ore

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2016年第7期23卷 731-742页

作者： Nathália Vieceli fernando O.Durao Carlos Guimaraes Carlos A.Nogueira Manuel F.C.Pereira Fernanda Margarido Center for Innovation Technology and Policy Research-IN+Instituto Superior T6cnicoUniversity of Lisbon1049-001 LisboaPortugal CeReNA-Centro de Recursos Naturais e Ambiente DECivilInstituto Superior TecnicoUniversity of Lisbon1049-001 LisboaPortugal LNeG-Laboratorio Nacional de energia e Geologia I.P.Campus do Lumiar1649-038 LisboaPortugal

The number of published studies related to the optimization of lithium extraction from low-grade ores has increased as the demand for lithium has grown. However, no study related to the kinetics of the concentration stage of lithium-containing minerals by froth flotation has yet been reported. To establish a factorial design of batch flotation experiments, we conducted a set of kinetic tests to determine the most selective alternative collector, define a range of pulp p H values, and estimate a near-optimum flotation time. Both collectors（Aeromine 3000 C and Armeen 12D） provided the required flotation selectivity, although this selectivity was lost in the case of pulp p H values outside the range between 2 and 4. Cumulative mineral recovery curves were used to adjust a classical kinetic model that was modified with a non-negative parameter representing a delay time. The computation of the near-optimum flotation time as the maximizer of a separation efficiency（Se） function must be performed with caution. We instead propose to define the near-optimum flotation time as the time interval required to achieve 95%–99% of the maximum value of the Se function.

关键词： lepidolite lithium ore treatment froth flotation kinetic analysis

O_(3) based advanced oxidation for ibuprofen degradation

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical engineering 2022年第2期35卷 277-284页

作者： Vitória M.Almeida Carla A.Orge M.fernando R.Pereira O.SaloméG.P.Soares Laboratory of Separation and Reaction engineering-Laboratory of Catalysis and Materials (LSRE-LCM)Faculdade de Engenharia da Universidade do PortoRua Dr.Roberto Frias4200-465 PortoPortugal

The degradation of the anti-inflammatory ibuprofen(IBP)was evaluated by several advanced oxidation *** was treated by single ozonation and oxidation with hydrogen peroxide(H_(2)O_(2)),as well as a combination of these *** order to improve the efficiency,the presence of catalysts such as original carbon nanotubes,labelled as CNT,and iron oxide supported on carbon nanotubes,named as Fe/CNT sample,was *** evolution of IBP degradation,mineralization and toxicity of the solutions was *** formation of intermediates was also *** the non-catalytic processes,IBP was faster removed by single ozonation,whereas no significant total organic carbon(TOC)removal was *** with H_(2)O_(2) did not present satisfactory *** ozone and H_(2)O_(2) were combined,a higher mineralization was attained(70%after 180 min of reaction).On the other hand,in the catalytic processes,this combined process allowed the fastest IBP *** terms of mineralization degree,the presence of Fe/CNT increases the removal rate in the first hour of reaction,achieving a TOC removal of 85%.Four compounds were detected as *** treated solutions presented lower toxicity than the initial solution,suggesting that the released intermediates during applied processes are less toxic.

关键词： Advanced oxidation processes Catalysts emerging pollutants Ibuprofen

Direct electrochemical Determination of Glyphosate Herbicide Using a Screen-Printed Carbon electrode Modified with Carbon Black and Niobium Nanoparticles

在线全文

学校读者我要写书评

暂无评论

Journal of Analysis and Testing 2023年第4期7卷 425-434页

作者： Julia Oliveira Fernandes Cassiano Augusto Rolim Bernardino Juliana dos Santos Fernandes Claudio fernando Mahler Bernardo Ferreira Braz Luiz Henrique Carpenter dos Santos Rodrigo JoséCorrêa Ricardo erthal Santelli Braulio Soares Archanjo emerson Schwingel Ribeiro fernando Henrique Cincotto Departament of Analytical Chemistry Institute of ChemistryFederal University of Rio de JaneiroRio de Janeiro 21941-909Brazil Departament of Civil engineering COPPEFederal University of Rio de JaneiroRio de Janeiro 21941-598Brazil National Institute of Science&Technology of Bioanalytics(INCTBio) CampinasSão Paulo 13083-862Brazil Departament of Inorganic Chemistry Institute of ChemistryFederal University of Rio de JaneiroRio de Janeiro 21941-909Brazil Unesp National Institute of Alternative Technologies for DetectionToxicological Assessment and Removal of Micropollutants and Radioactives(INCT-DATREM)AraraquaraSão Paulo 14800-060Brazil National Institute of Metrology Quality and TechnologyInmetroAv.Nossa Senhora das Graças50XerémDuque de Caxias 25250-020Brazil

Glyphosate is a herbicide that has been widely used worldwide and is used in agricultural areas to control weeds and unwanted *** sensors developed from different nanomaterials have high efficiency,excellent cost-benefit,and fast analysis time for detecting traces of environmental *** study aimed to produce an electrochemical sensor with disposable screen-printed electrodes based on carbon black modified with niobium nanoparticles to determine glyphosate in aqueous *** morphology,structure and electrochemical performance of the sensor were characterized by scanning electron microscopy,energy-dispersive X-ray spectroscopy,X-ray diffraction and cyclic *** pulse voltammetry in BR buffer solution at pH 5.0 allowed the generation of a method to quantify glyphosate concentration in a linear range of 5.90-172.30μmol/L(1.00-29.13μg/mL),with a limit of detection calculated at 3.07μmol/L(0.52μg/mL).The method efficiently quantified glyphosate in real water samples and showed no interference from K^(+),Na^(+),Ca^(2+),Mg^(2+)ions or thiamethoxam,imidacloprid and carbendazim pesticides.

关键词： Glyphosate electrochemical sensor Carbon black Niobium nanoparticles

N<sub>2</sub>O Formation in Selective Non-catalytic NO<sub>x</sub>Reduction Processes

在线全文

学校读者我要写书评

暂无评论

Journal of environmental Protection 2011年第8期2卷 1095-1100页

作者： Crisanto Mendoza-Covarrubias Carlos e. Romero fernando Hernandez-Rosales Hans Agarwal 不详

Nitrous oxide is not an environmentally regulated species in the U.S., but it does participate in the stratospheric ozone chemistry and contributes to the greenhouse effect. Nitrous oxide has been found to be a by-product of the selective non-catalytic reduction process. Chemical kinetic calculations demonstrated that the formation of nitrous oxide in the urea-based selective non-catalytic reduction process is linked to the conversion of NO by cyano species released from the process parent compounds. This conversion occurs within in temperature window between 850 and 1050℃. With urea injection, nitrous oxide emissions represent up to 20 percent conversion of the NOx reduced. The amount of nitrous oxide formed depends primarily on the process temperature, the amount of chemical injected, the initial NOx level, and the carbon monoxide level in the gas stream. These observations, which were based on the chemical kinetics of the process, should be considered in designing selective non-catalytic reduction systems to minimize nitrous oxide by- product formation.

关键词： Selective Non-Catalytic Reduction Process Nitrous Oxide emissions Chemical Kinetics