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Influence of lanthanum as additive and post-treatment on the corrosion protection properties and surface morphology of mild steel chemically treated by a cerium conversion coating

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Journal of Rare Earths 2018年第10期36卷 1112-1120页

作者： z.Mahidashti B.Ramezanzadeh Department of Surface Coatings and Corrosion Institute for Color Science and Technology (ICST)

The influence of cerium conversion coating（CeCC） modified by lanthanum in two forms of additive and post-treatment solution on the corrosion resistance, surface morphology and surface chemistry of the mild steel was studied. Corrosion resistance was evaluated by electrochemical impedance spectroscopy,while the scanning electron microscopy, X-ray photoelectron spectroscopy and contact angle test were employed to investigate the surface characteristics. Results reveal that the CeCC post-treated by lanthanum containing solution gives rise to the deposition of a crack free and uniform conversion coating with enhanced corrosion resistance on the steel surface. Also, the surface free energy is increased after post-treatment.

关键词： Surface treatment Corrosion resistance XPS AFM SEM/EDS Surface free energy

Slip effects on streamline topologies and their bifurcations for peristaltic flows of a viscous fluid

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Chinese Physics B 2014年第6期23卷 341-352页

作者： z.Asghar N.Ali Department of Mathematics and Statistics International Islamic University

We discuss the effects of the surface slip on streamline patterns and their bifurcations for the peristaltic transport of a Newtonian fluid. The flow is in a two-dimensional symmetric channel or an axisymmetric tube. An exact expression for the stream function is obtained in the wave frame under the assumptions of long wavelength and low Reynolds number for both cases. For the discussion of the particle path in the wave frame, a system of nonlinear autonomous differential equations is established and the methods of dynamical systems are used to discuss the local bifurcations and their topological changes. Moreover, all types of bifurcations and their topological changes are discussed graphically. Finally, the global bifurcation diagram is used to summarize the bifurcations.

关键词： viscous fluid slip condition streamline topologies bifurcation

Importance of diet and intestinal microbiota in the prevention of colorectal cancer-colonoscopy early screening diagnosis

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3428-3435页

作者： Miljana z Jovandaric Department of Neonatology Clinic for Gynecology and ObstetricsUniversity Clinical Center of SerbiaBelgrade 11070Serbia

Colorectal cancer is a term used to describe colon and rectal cancer,which is the third most common type of cancer.A MEDLINE and PubMed search resulted in the inclusion of manuscripts written in the last 10 years,using keywords relevant to the topic of the *** analyzing the aim of the searched studies and manuscripts,adequate articles were included that described the stated *** frequency of colorectal cancer varies with climate,nutrition,and many other factors,primarily endogenous,hereditary,intestinal microbiome,as well as external factors,such as exposure of the individual to stress,and bad eating *** cancer and rectal cancer or colorectal cancer in general in the early stages of the disease,may not show symptoms or are barely *** cancer symptoms will most often not develop until the disease has progressed to stage 2 or *** screening tests for colon or rectal cancer,especially colonoscopy,are recommended as part of a regular checkup for people aged 50 years or younger who are at high risk due to a family history of the disease or other *** and colonoscopy as an early screening method play an important role in the prevention of colorectal cancer.

关键词： Colorectal cancer Causes Symptoms Screening Diet and colonoscopy

BOUNDARY ELEMENT APPROXIMATION OF STEKLOV EIGENVALUE PROBLEM FOR HELMHOLTz EQUATION

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Journal of Computational Mathematics 1998年第2期16卷 165-178页

作者： Tang, WJ Guan, z Han, HD Inst Appl Phys & Computat Math Lab Computat Phys Beijing 100088 Peoples R China Tsing Hua Univ Dept Appl Math Beijing 100084 Peoples R China

Steklov eigenvalue problem of Helmholtz equation is considered in the present paper. Steklov eigenvalue problem is reduced to a new variational formula on the boundary of a given domain, in which the self-adjoint property of the original differential operator is kept and the calculating of hyper-singular integral is avoided. A numerical example showing the efficiency of this method and an optimal error estimate are given.

关键词： Steklov eigenvalue problem differential operator error estimate boundary element approximation

Decolorization of Direct Black 22 by Aspergillus ficuum

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Journal of Environmental Sciences 2001年第4期13卷 472-475页

作者： Dong, X.-j. Du, z.-y. Chen, z. Dept. of Biology/Environmental Sci. Wenzhou Normal College Wenzhou 325003 China

The decolorization of Direct Black 22 by Aspergillus ficuum has been studied. It was found that Aspergillus ficuum could effectively decolorize Direct Black 22 especially when grown as pelleted mycelia. Results showed that the media containing Direct Black 22 at 50 mg/L could be decolorized by 98.05% of the initial color in 24 h. The optimum pH and temperature of decolorization are 4.0 and 33 °C respectively. Aeration was quite beneficial to decolorization. Medium composition and the concentration of Direct Black 22 could affect the rate of decolorization. The dye degraded products assayed by UV-visible spectrophotometer and macroscopic observation showed that the decolorization of Direct Black 22 by mycelial pellets includes two important processes: bioadsorption and biodegradation. The degradation experiment agree with the Michaelis-Menten kinetics equation.

关键词： Bioassay Biodegradation Color Concentration (process) Dyes pH Ultraviolet spectrophotometers

RANDOM-FUzzY SAFETY ANALYSIS FOR AN AERO ENGINE TURBINE DISK

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 509-513页

作者： z.z.Lü C.L.Liu Y.L.Xu z.F.Yue School of Aviation Northwestern Polytechnical University Xi'an 710072 ChinaSchool of Aviation Northwestern Polytechnical University Xi'an 710072 ChinaChina Aviation Research Institute 608 Zhuzhou 412002 ChinaSchool of Mechanics Civil Engineering and Architecture Northwestern Polytechnic University Xi'an 710072 China

A numerical simulation method is presented for the random-fuzzy safety analysis of an aero engine disk. Based on the equivalent transformation from a fuzzy variable to a random variable, the equivalent random Probability Density Functions(PDFs) are got from their corresponding Fuzzy Possibility Distributions(FPDs) for the fuzzy variables. In that case the perfect numerical simulation method for the random uncertainty is employed to solve the fuzzy uncertainty. For the complex structure such as the aero engine disk with implicit relationship between the input basic variable and the response variable, the equivalent PDFs of the input basic variables are delivered simultaneously to the response variable by an empirical PDF, which is simulated by Finite Element Method(FEM). Then, in view of the fuzzy application requirement occurring in engineering usually, the reliability definition and calculation are discussed for the aero engine disk with multiple fuzzy failure modes. On the other hand, through the inverse transformation of the fuzzy variable to the random variable, the FPDs of the response variables can be calculated from their empirical PDFs as well.

关键词： random fuzzy turbine disk reliability

Radioisotopes and Analytical Chemistry

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World Journal of Nuclear Science and Technology 2013年第1期3卷 6-13页

作者： Manuel Navarrete Trinidad Martínez Alberto Fernández Miguelángel zúniga Michelle Camacho Mónica Flores Department of Inorganic and Nuclear Chemistry Faculty of ChemistryNational University of MexicoMexico CityMexico

When Periodic Chart of elements is consulted to find natural radioisotopes, one firstly finds tritium, followed by 10Be, 14C, 50V and many others. Before Bi, 12 cosmogenic radioisotopes are listed. They are those continuously produced by nuclear reactions among light elements present in earthly atmosphere and radiations coming from the outside space. Eighteen additional primordial radioisotopes are listed. They were created at the same time that the non-radioactive isotopes composing the 92 natural elements in the periodic table. From Bi on, every isotope is radioactive, up to U. Then follow the artificial elements produced by laboratory nuclear reactions from Np to element with atomic number 118. In this way, from 118 known elements, 64 are radioactive, which amount 55% of all those units forming the chemical compounds. Therefore, the complete understanding of radioactivity should be a suitable tool to advance our knowledge of Universe, and consequent applications to get better living conditions. So, this paper deals with radioisotopes as suitable instruments for chemical analysis.

关键词： Radioisotopes Radiations Chemical Quantitative Analysis

Fecal microbiota transplantation in allergic diseases

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World Journal of Methodology 2025年第2期15卷 83-91页

作者： Ece TüsüzÖnata ÖnerÖzdemir Division of Pediatric Allergy and Immunology Medical FacultySakarya UniversityAdapazarı54100SakaryaTürkiye

Microorganisms such as bacteria,fungi,viruses,parasites living in the human intestine constitute the human intestinal *** refers to composi-tional and quantitative changes that negatively affect healthy gut *** recent years,with the demonstration that many diseases are associated with dysbiosis,treatment strategies targeting the correction of dysbiosis in the treat-ment of these diseases have begun to be *** microbiota trans-plantation(FMT)is the process of transferring faeces from a healthy donor to another recipient in order to restore the gut microbiota and provide a therapeutic *** studies have gained popularity after probiotic,prebiotic,symbiotic studies in the treatment of dysbiosis and related *** has emerged as a potential new therapy in the treatment of allergic diseases as it is associated with the maintenance of intestinal microbiota and immunological balance(T helper 1/T helper 2 cells)and thus suppression of allergic *** this article,the definition,application,safety and use of FMT in allergic diseases will be discussed with current data.

关键词： Microbiota Dysbiosis Faecal microbiota transplantation Allergic diseases

Effect of rolling friction on wall pressure,discharge velocity and outflow of granular material from a flat-bottomed bin

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Particuology 2012年第6期10卷 672-682页

作者： R.Baleviius I.Sielamowicz z.Mróz R.Kaianauskas Department of Reinforced Concrete and Masonry Structures Vilnius Gediminas Technical Universityav.Sauletekio 11LT-10223 VilniusLithuania Composite Silo Systems ORCHIDEA st.J.Matejki 815-196 BialystokPoland Institute of Fundamental Technological Research Polish Academy of Sciencesst.Pawin'skiego 5b02-106 WarsawPoland Institute of Mechanics Vilnius Gediminas Technical Universityst.J.Basanaviiaus.28LT-10223 VilniusLithuania

The present paper provides both experimental and DEM analyses of the filling and discharge of pea grains from a 3D flat-bottomed bin. In the DEM model, the fixed mean values of the experimentally determined single particle data, such as the particle density, Young＇s modulus, Poisson＇s ratio as well as the sliding and rolling friction coefficients were incorporated to analyse their effects on the macroscale indicators, such as the wall pressure, discharge velocities and material outflow parameters. The effect of rolling friction was studied based on the experimentally measured single particle rolling friction coefficient. This analysis is aimed at the quantitative prediction of flow parameters as related to the identification of material parameters.

关键词： Visco-elastic granular materia Discrete element method Rolling friction Wall pressure Material velocityOutflow mass Outflow rateBiosystems Pea grains