检索结果-南通市图书馆

Biostratigraphy and palaeoenvironment of deposition of Nsukka Formation,Anambra Basin,southeastern Nigeria

在线全文

学校读者我要写书评

暂无评论

Journal of Palaeogeography 2017年第1期6卷 45-59页

作者： s.A.Bankole A.O.Ola-Buraimo Department of Chemical and Geological sciences Al-Hikmah UniversityllorinNigeria Department of Geology Federal UniversityBimin KebbiNigeria

Biostratigraphy investigation of Nsukka Formation was carried out by subjecting weLt cutting samples obtained from Nzam-1 weLL to patynotogicat studies with the view towards determining the relative geologic age and pataeoenvironment of deposition of the sediments. sampLes were treated in the Laboratory through digestion with hydrofluoric acid, sieving with 5 μm, oxidation with Nitric acid and mounting of the sLides into sections with DPX mountant. A fairLy high abundance and diversity of miospores were recovered, white the interval （847-1372 m） contains distinctive and diagnostic patynomorphs which are stratigraphicatty important. A spinizonocolpites baculatus assemblage zone was established based on the basal occurrence of s. baculatus, spinizonocolpites echinatus, Constructipollenites ineffectus, Periretisyncolpites sp. Periretisyncolpites giganteus, Monocolpites sp 1, Foveotriletes margaritae, syncolporites marginatus, and Longapertites marginatus. The upper part of the intervat is marked by association of Anacolosidites luidonisis （at top）, Mauritiidites crassibaculatus, Retistephanocolpites williamsi, Proteacidites dehaani, Echitriporites trianguliformis, Proxapertites cursus, Retidiporites magdalenensis, s. baculatus, Retitricolpites gigeonetti, F. margaritae and Araucariadtes sp. The Nsukka Formation is dated as Late Maastrichtian based on the cooccurrence of recovered index fossits. Importantly, Cretaceous-Tertiary （K/T） boundary is marked by high fossil content in the Maastrichtian sediments compared to paucity in patynomorph that characterises the overtying Pateocene facies. Pataeoenvironment of the anatyzed section varies atternatety from marginaL marine to continental setting based on the presence of land-derived miospores and dinoflagettates.

关键词： Biostratigraphy Palaeoenvironment Assemblage Gonyaulacacean/Peridinacean ratio Index fossil Anambra Basin

Limsup Results and LIL for Partial sum Processes of a Gaussian Random Field

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica sinica,English series 2008年第9期24卷 1497-1506页

作者： Yong-Kab CHOI Mikls CsRG Department of Mathematics and RINs Gyeongsang National University Jinju 660-701 Republic of Korea school of Mathematics and statistics Carleton University 1125 Colonel By DriveOttawa K1S 5B6 Canada

Let {ξ j ; j ∈ ℤ+ d be a centered stationary Gaussian random field, where ℤ+ d is the d-dimensional lattice of all points in d-dimensional Euclidean space ℝd, having nonnegative integer coordinates. For each j = (j ... 详细信息

Let {ξsUB> j sUB>; j ∈ ℤsUB>+sUB>sUP> d sUP>be a centered stationary Gaussian random field, where ℤsUB>+sUB>sUP> d sUP>is the d-dimensional lattice of all points in d-dimensional Euclidean space ℝsUP>dsUP>, having nonnegative integer coordinates. For each j = (j sUB>1 sUB>, ..., jd) in ℤsUB>+sUB>sUP> d sUP>, we denote |j| = j sUB>1 sUB>... j sUB>d sUB>and for m, n ∈ ℤsUB>+sUB>sUP> d sUP>, define s(m, n] = ΣsUB> msUB>ζsUB> j sUB>, σsUP>2sUP>(|n−m|) = Es sUP>2 sUP>(m, n], s sUB>n sUB>= s(0, n] and s sUB>0 sUB>= 0. Assume that σ(|n|) can be extended to a continuous function σ(t) of t > 0, which is nondecreasing and regularly varying with exponent α at b ≥ 0 for some 0 some additional conditions, we study limsup results for increments of partial sum processes and prove as well the law of the iterated logarithm for such partial sum processes.

关键词： stationary Gaussian random field regularly varying function large deviation probability law of the iterated logarithm

Geochemistry of Kestelek Colemanite Deposit, Bursa, Turkey

在线全文

学校读者我要写书评

暂无评论

Journal of Earth science 2017年第1期28卷 63-77页

作者： sükrü Koc Ozge Kavrazh ismail Kocak Faculty of Department of Geological Engineering Ankara University Ankara 06100 Turkey Graduate school of Natural and Applied sciences Ankara University Ankara 06100 Turkey Department of Geological Engineering Bozok University Yozgat 66100 Turkey

The Kestelek borate deposit has been the subject of geological and mineralogical research over the last decades, but major and trace element geochemistry of this deposit was first investigated in the present study. A total of 22 samples collected from surface exposures and different depths of deposit in boreholes（e.g., lower, middle and upper） comprise the material of this study. Major, trace and REE element analyses of samples were conducted with ICP-Ms and ICP-Es methods. The Kestelek borate deposit of Miocene age was formed in playa lakes in an intermountain closed basin which was developed in volcanically and seismically active areas associated with growth faults and grabens affected the whole Anatolia at the beginning of Paleogene. Only colemanite was found as the borate mineral accompanied in lesser amount by calcite, aragonite, smectite, illite, chlorite, corrensite, heulandite and quartz. In colemanite samples, all major elements, except for Ca, show depletion trends with respect to average of earth crust and andesite. For the trace elements, Li, Cs, sb, As, sr and se are characterized by significantly high concentrations. Evaluation of element concentrations and geochemical characteristics reveal that As, Cs, sb and Li are of detrital origin, se together with B and Ca are of non-detrital and sr is indicative of both detrital and non-detrital origin. REE distributions indicate that at least two different depositional regimes prevail in the environment. Corrensite, a clay mineral forming in lake waters, is derived from volcanism. Negative Ce and positive Eu anomalies are indicative of contribution from hydrothermal solutions and fluids.

关键词： borate mineralogy geochemistry REE Kestelek Turkey.

A data-driven approach to π^0,η and η＇ single and double Dalitz decays

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2018年第2期42卷 89-105页

作者： Rafel Escribano sergi Gonzàlez-solís Crup de Fisica Tebrica Departament de Fisica Universitat Autbnoma de Barcelona E-08193 Bellaterra (Barcelona) Spain Institut de Fisica d'Altes Energies (IFAE) The Barcelona Institute of Science and Technology (BIST) Campus UAB E-08193 Bellaterra (Barcelona) Spain CAs Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 China

The dilepton invariant mass spectra and integrated branching ratios of the single and double Dalitz decays P→l^＋l^-γ and P→l^＋l^-l^＋l^-（P=π^0,η,η＇;l=e or μ） are predicted by means of a data-driven approach based on the use of rational approximants applied to π^0,η and η＇ transition form factor experimental data in the space-like region.

关键词： electromagnetic processes and properties phenomenological models transition form factor

Acrylamide: the new dilemma in food safety

在线全文

学校读者我要写书评

暂无评论

中国药理学与毒理学杂志 2006年第3期20卷 164-165页

作者： s sRIANUJATA Institute of Nutrition Mahidol University salaya Putthamonthon Nakhonpathom 73170 Thailand

Acrylamide has been brought to the world attention in 2002 with the information that it was found contaminated in many heat treated carbohydrate rich foods. This creates a lot of concern worldwide since the appearance of Aflatoxins many decades ago. The dilemma occurs as the heat treated carbohydrate rich foods are being consumed by population around the world while the high in complex carbohydrate diet is being promoted by international organizations as FAO and WHO in the effort for the prevention of some chronic diseases.

关键词： dilemma coffee developmental

An Intelligent Gestational Diabetes Diagnosis Model Using Deep stacked Autoencoder

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2021年第12期69卷 3109-3126页

作者： A.sumathi s.Meganathan BVijila Ravisankar sRC SASTRA Deemed to be UniversityKumbakonamTamil Nadu612001India Consultant Obstetrician and Gynecologist Anbu Hospital and Nalam ClinicKumbakonamTamil Nadu612001India

Gestational Diabetes Mellitus(GDM)is one of the commonly occurring diseases among women during *** Glucose Tolerance Test(OGTT)is followed universally in the diagnosis of GDM diagnosis at early pregnancy which is costly and ***,there is a need to design an effective and automated GDM diagnosis and classification *** recent developments in the field of Deep Learning(DL)are useful in diagnosing different *** this view,the current research article presents a new outlier detection with deep-stacked Autoencoder(OD-DsAE)model for GDM diagnosis and *** goal of the proposed OD-DsAE model is to find out those mothers with high risks and make them undergo earlier diagnosis,monitoring,and treatment compared to low-risk *** presented ODDsAE model involves three major processes namely,preprocessing,outlier detection,and *** the first step i.e.,data preprocessing,there exists three stages namely,format conversion,class labelling,and missing value replacement using k-nearest neighbors(KNN)*** are superior values which considerably varies from other data ***,it might represent the variability in measurement,experimental errors or novelty ***,Hierarchical Clustering(HC)-based outlier detection technique is incorporated in OD-DsAE model,and thereby classification performance can be *** proposed model was simulated using Python 3.6.5 on a dataset collected by the researcher themselves.A series of experiments was conducted and the results were investigated under different *** experimental outcomes inferred that the OD-DsAE model has outperformed the compared methods and achieved high precision of 96.17%,recall of 98.69%,specificity of 89.50%,accuracy of 96.18%,and F-score of 97.41%.

关键词： Gestational diabetes mellitus data classification outlier detection deep learning hierarchical clustering

Effect of COOH-functionalized sWCNT addition on the electrical and photovoltaic characteristics of Malachite Green dye based photovoltaic cells

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of semiconductors 2014年第12期35卷 32-37页

作者： s.Chakraborty N.B.Manik Condensed Matter Physics Research Center Department of Physics Jadavpur University

We report the effect of COOH-functionalized single walled carbon nanotubes（COOH-sWCNT） on the electrical and photovoltaic characteristics of Malachite Green（MG） dye based photovoltaic cells. Two different types of photovoltaic cells were prepared, one with MG dye and another by incorporating COOH-sWCNT with this dye. Cells were characterized through different electrical and photovoltaic measurements including photocurrent measurements with pulsed radiation. From the dark current–voltage（I–V） characteristic results, we observed a certain transition voltage（Vth/ for both the cells beyond which the conduction mechanism of the cells change sharply. For the MG dye, Vthis 3.9 V whereas for COOH-sWCNT mixed with this dye, Vthdrops to 2.7 V. The device performance improves due to the incorporation of COOH-sWCNT. The open circuit voltage and short circuit current density change from 4.2 to 97 m V and from 108 to 965 A/cm2 respectively. Observations from photocurrent measurements show that the rate of growth and decay of the photocurrent are quite faster in the presence of COOH-sWCNT. This observation indicates a faster charge separation processes due to the incorporation of COOHsWCNT in the MG dye cells. The high aspect ratio of COOH-sWCNT allows efficient conduction pathways for the generated charge carriers.

关键词： MG dye COOH-sWCNT photovoltaic devices charge transport

Evaluation of Immunological Markers in Children Infected with Intestinal Parasites in Three Communities, Nigeria

在线全文

学校读者我要写书评

暂无评论

Open Journal of Immunology 2023年第2期13卷 45-59页

作者： Eze Chinwe Nwadiuto Jonah s. Aprioku Department of Animal and Environmental Biology University of Port Harcourt Choba Nigeria Department of Pharmacology Faculty of Pharmacy University of Port Harcourt Choba Nigeria

Helminthiases are neglected parasites that induce changes in the host’s immune response. The study assayed some immunological markers in helminth infections in children and adolescents. stool and blood samples were collected from 276 subjects resident in three rural communities of Rivers and Imo states. Of these, 98 (35.5%) were infected with one or more of 3 parasitic species, of which Ascaris lumbricoides 39 (39.8%), Ancylostoma duodenale 30 (30.6%) and Trichuris trichiura 29 (29.6%) were recovered. Intestinal helminth parasites were identified using formol-ether concentration. Of the infected subjects, 66 had single species infections and 32 had multiple infections with two or three helminth species and children of the 6 - 10 years age group had the highest incidence. sera of 60 infected subjects and 30 controls were evaluated to define immunological serum levels of IgE, IL-5, IFN-γ and C3 using the ELIsA technique, while white blood cell differential counts and neutrophil-lymphocyte ratio (NLR) were evaluated using haematology auto-analyser. Elevation of IL-5, IgE, WBC and eosinophil levels were demonstrated in the infected groups (p s, compared to the control. Their concentrations across the different age groups were also significantly different (p = 0.0001), the highest in 6 - 5 years and the lowest in 0 - 5 years. Differences in IFN-γ and C3 levels among non-parasitized, single-parasitized and poly-parasitized groups were not statistically significant. Neutrophil, lymphocyte and NLR levels between control and helminth infected subjects were not significantly different. The result suggested that IgE, IL-5, total WBC and eosinophil increased in helminth infections, more in poly-parasitized and 6 - 10 years children.

关键词： Immune Response Parasites Helminth Neutrophil

Experimental investigation into fabrication of microfeatures on titanium by electrochemical micromachining

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Manufacturing 2016年第2期4卷 167-177页

作者： sandip s. Anasane B. Bhattacharyya Department of Production Engineering Jadavpur UniversityKolkata India

Titanium machining is one of the challenging tasks to modem machining processes. Especially fabricat- ing microfeatures on titanium appear as a potential research interest. Electrochemical micromachining （EMM） is an effective process to generate microfeatures by anodic dis- solution. Machining of titanium by anodic dissolution is different than other metals because of its tendency to form passive oxide layer. The phenomenon of progression of microfeature by conversion of passive oxide layer into transpassive has been investigated with the help of mask- less EMM technique. suitable range of machining voltage has been established to attain the controlled anodic disso- lution of titanium by converting passive oxide film of titanium into transpassive with nonaqueous electrolyte. The experimental outcomes revealed that the micromachining of titanium with controlled anodic dissolution could be possible even at lower machining voltage in the range of 6-8 V. This work successfully explored the possibility of generation of microfeatures on commercially pure titanium by anodic dissolution process in microscopic domain by demonstrating successful fabrication of various microfea- tures, such as microholes and microcantilevers.

关键词： Titanium machining Electrochemicalmicromachining (EMM) Anodic dissolution Currentdensity Current efficiency