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International Journal of Minerals,Metallurgy and Materials 2017年第2期24卷 179-185页

作者： v.v.Ravikumar s.Kumaran Department of Metallurgical and Materials Engineering National Institute of TechnologyTamil Nadu 620015India

Al-12Zn-3Mg-2.5Cu alloy was prepared using a liquid metallurgy route under the optimized conditions. A sample cut from the ingot was rolled non-isothermally from 400℃ to 100℃ in 100℃ steps, with 15% reduction in thickness; it was then cold rolled isothermally at room temperature for 85% reduction. The cold-rolled alloys were characterized by electron microscopy, hardness test, and tensile test to elucidate their structural evolution and evaluate their mechanical behavior. In the results, the cast alloy consists of a-aluminum and various intermetallic compounds. These compounds are segregated along the grain boundaries, which makes the alloy difficult to roll at room tem- perature. The combined effect of non-isothermal step rolling and cold rolling results in the nano/microsized compounds distributed uniformly in the matrix. The hardness is substantially increased after rolling. This increase in hardness is attributed to the ultra-fine grain size, fine-scale intermetallic compounds, and structural defects （e.g., dislocations, stacking faults, and sub-grains）. The ultimate tensile strength of the rolled alloy is approximately 628 MPa with 7% ductility.

关键词： aluminum zinc magnesium copper alloys non-isothermal cold rolling mechanical properties intermetallic compounds struc-ture defects

Phylogenetic analysis and protective effects of thymol and its chromatographic fractions from a novel wild mushroom in combating oxidative stress

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Food science and Human Wellness 2021年第4期10卷 452-459页

作者： M.subbulakshmi sugapriya Dhanasekaran s.Abirami M.Kannan R.Palaniappan divya venugopal Department of Microbiology K.R.College of Arts and ScienceKovilpattiTamil NaduIndia Department of Medical Laboratory sciences College of Applied Medical SciencesPrince Sattam Bin Abdulaziz UniversityWadi Al DawaserSaudi Arabia Department of Microbiology Kamaraj CollegeThoothukudiTamil NaduIndia Research Department of Zoology V.H.N.Senthikumara Nadar College(Autonomus)VirudhunagarTamil NaduIndia Research Department of Computer science V.H.N.Senthikumara Nadar College(Autonomus)VirudhunagarTamil NaduIndia

Mushrooms are good sources of phytochemicals that have antioxidant and anti-proliferative *** study identifi ed a unique isoform of 18s rRNA gene(864 bp)from a novel wild mushroom(sMK-1)(GenBank accession number:sUB3267363).Thin layer chromatographic(TLC)profiling of the methanolic extract of the dried mushroom fruiting bodies of sMK-1 revealed the presence of phenolic and fl avonoid fractions with retention factor(Rf)values of 0.955 and 0.927 *** GC/Ms chromatograms of the sMK-1 methanolic extract identifi ed the main bioactive compound was phenol,5-methyl-2-(1-methylethyl)(74.00%)(thymol).The radical scavenging activity for the fl avonoid fraction was greater than the phenolic fractions(Rf–phenolics fractions>Rf–fl avonoid fractions)with the antioxidant activity more than that of standard ascorbic ***,the phenolic and flavonoid fractions of sMK-1 expressed cytotoxic effects in HeLa cells with IC50 values ranging from 5μg/mL to 80μg/mL in a dose-dependent *** present research highlights the presence of high thymol concentration in a novel wild mushroom that has antioxidant and anti-poliferative potential with therapeutic benefi *** application of thymol natural products from novel mushroom sMK-1 as nutrition supplements could inhibit oxidative stress triggered by numerous pathologies that may pave the way to develop a new therapeutic natural drug.

关键词： Antioxidant Anti-proliferation Dietary mushrooms HeLa cells Novel Mushrooms Thymol

The detailed corrosion performance of bioresorbable Mg-0.8Ca alloy in physiological solutions

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Journal of Magnesium and Alloys 2022年第5期10卷 1326-1350页

作者： A.s.Gnedenkov s.L.sinebryukhov v.s.Filonina v.s.Egorkin A.Yu.Ustinov v.I.sergienko s.v.Gnedenkov Institute of Chemistry of FEB RAs 159 Pr.100-letiya VladivostokaVladivostok690022Russia

The electrochemical behaviour of biodegradable magnesium alloy Mg-0.8Ca was evaluated in a mammalian cell culture medium(MEM)and Na Cl solutions(0.9 wt.%, 0.3 wt.%) using traditional(EIs, PDP, OCP) and local scanning electrochemical(svET, sIET with p H-selective microelectrode) methods at the micro-and meso-level. Corrosion rates of samples in two different media were determined using weight loss tests. The influence of testing media components, alloy composition and microstructure on the material’s degradation process was *** svET/sIET test parameters were optimized for in vitro investigation of the bioresorbable material surface. The mechanism of the alloy’s bioresorption was suggested. The effect of microsized phases on the corrosion behaviour of the alloy was proved using complementary in situ monitoring and sKPFM measurements. The rapid degradation rate of the alloy is related to the presence of local microgalvanic cells formed by cathodic α-magnesium matrix and anodic Mg_(2)Ca phase. The highest corrosion activity was revealed in the first 12 min of sample exposure to MEM, followed by stabilization of corrosion process due to the material’s passivation. Using sEM-EDX analysis, micro-Raman spectroscopy and XPs analysis the composition of the corrosion products was determined. Degradation in MEM proceeds with a formation of magnesium-and-carbonate substituted hydroxyapatite-containing film on the sample’s surface. The low possibility of application of Mg-0.8Ca alloy without coating protection in implant surgery was highlighted.

关键词： Magnesium-calcium alloy Biodegradation Corrosion rate Electrochemistry Weight loss Minimum essential medium

A comparison of zooplankton assemblages in Nansi Lake and Hongze Lake,potential influences of the East Route of the south-to-North Water Transfer Project,China

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Journal of Oceanology and Limnology 2021年第2期39卷 623-636页

作者： Kandathil Radhakrishnan divya shasha ZHAO Yushun CHEN Fei CHENG Lei ZHANG Jiao QIN Thundiparambil sathrajith ARUNJITH v.Bjorn sCHMIDT songguang XIE Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of sciences Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China Key Laboratory of sustainable Fisheries and Environmental Protection for Lakes of Northern Jiangsu Huai’an Research CenterInstitute of HydrobiologyChinese Academy of SciencesHuai’an 223002China

Nansi Lake and Hongze Lake are both water storage lakes along the East Route of the south-to-North Water Transfer project(EsNT).Frequent changes in hydrologic properties are responsible factors for controlling the zooplankton community assemblages in both lakes,so we studied the possible influence of water transfer and environmental factors on zooplankton community structure and *** assemblages were investigated seasonally for one year in both lakes;a total of 133 and 122 zooplankton taxa were identified in Nansi Lake and Hongze Lake,*** most dominant rotifer species were littoral,e.g.,Keratella tecta,Keratella valga and Lecane lunaris in Nansi Lake and Brachionus angularis,Brachionus forficula and Polyarthra vulgaris in Hongze ***,Nansi Lake had a higher shannon-Wiener diversity index value(5.13),while Hongze Lake had a higher species richness index(4.21).The average number of zooplankton across seasons in Nansi Lake(protozoa:774±63 ind./L,rotifers:4817±212 ind./L,cladocerans:896±14 ind./L,copepod:435±42 ind./L)was comparatively lower than Hongze Lake(protozoa:1238±63 ind./L,rotifers:6576±112 ind./L,cladocerans:1013±20 ind./L,copepod:534±25 ind./L).Canonical correspondence analysis identified differing environmental gradients that were most responsible for influencing zooplankton communities in the two lakes(Hongze Lake:NH4-N,total nitrogen,transparency and pH;Nansi:pH,temperature and total phosphorus).Frequent changes related to water transfer in lakes favoured the diversity of rotifers and protozoa *** habitat preference,changes in community structure and opportunistic peaks and extinction of certain taxa were also observed in the study lakes.

关键词： zooplankton assemblage water transfer Hongze Lake Nansi Lake

Hydroxyapatite-containing PEO-coating design for biodegradable Mg-0.8Ca alloy: Formation and corrosion behaviour

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Journal of Magnesium and Alloys 2023年第12期11卷 4468-4484页

作者： A.s.Gnedenkov s.L.sinebryukhov v.s.Filonina s.v.Gnedenkov Institute of Chemistry of FEB RAs 159 Pr.100-letiya VladivostokaVladivostok690022Russian Federation

In this study, the biocompatible protective coating was formed using plasma electrolytic oxidation(PEO) on bioresorbable Mg-0.8Ca alloy. The composition of the formed coating was studied using XRD, sEM-EDX analysis, and micro-Raman spectroscopy. The uniform distribution of hydroxyapatite over the thickness of protective PEO-layer was established. Using traditional(EIs, PDP, OCP) and local scanning electrochemical methods(svET, sIET with H^(+)-selective microelectrode), the level of protective properties of PEO-layer in a biological environment(mammalian cell culture medium, MEM) was determined. It was established that modification of Mg-0.8Ca alloy surface by PEO contributes to a significant increase in the corrosion resistance of the surface layer, making it possible to control the process of material‘s biodegradation. The maximum local electrochemical activity was recorded after 72 h of testing, while for the uncoated sample,intense corrosion degradation was recorded in the first 12 min of exposure to the cell culture medium. Formation of the PEO-coating results in a twofold decrease in the corrosion current density(2.8·10^(-6)A cm^(-2)) and an increase in the impedance modulus measured at a low frequency(1.7·10^(4)Ω cm^(2)) in comparison with the uncoated material(9.5·10^(-6)A cm^(-2);8.1·10^(3)Ω cm^(2)). The mechanism of material bioresorption was established and a model for biodegradation process of Mg-0.8Ca alloy with hydroxyapatite-containing PEO-coating in MEM was proposed. Analysis of these results and comparing with others obtained by various scientific groups indicate the prospects for application of biocompatible PEO-coating on Mg-Ca alloy in implant surgery.

关键词： Magnesium-calcium alloy Biodegradation Implant surgery Plasma electrolytic oxidation Electrochemistry Minimum essential medium Hydroxyapatite

Modelling Magnetoresistance Effect in Limited Anisotropic semiconductors

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Chinese Physics Letters 2017年第7期34卷 212-214页

作者： Filippov v.v. Mitsuk s.v. Lipetsk state Pedagogical University of P. P. semenov-Tyan-shansky Lipetsk 398020 the Russian Federation Lipetsk state Technical University Lipetsk 398600 the Russian Federation

A macroscopic model of the magnetoresistance effect in fimited anisotropic semiconductors is built. This model allows us to solve the problem of measurement of physical magnetoresistance components of crystals and films. Based on a unified mathematical model the method is worked out enabling us to measure tensor components of the specific electrical resistance and the relative magnetoresistance of anisotropic semiconductors simultaneously.

关键词： Modelling Magnetoresistance Effect in Limited Anisotropic semiconductors

Fault Pattern Diagnosis and Classification in sensor Nodes Using Fall Curve

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Computers, Materials & Continua 2022年第7期72卷 1799-1814页

作者： Mudita Uppal Deepali Gupta divya Anand Fahd s.Alharithi Jasem Almotiri Arturo Mansilla Dinesh singh Nitin Goyal Chitkara University Institute of Engineering and Technology Chitkara UniversityPunjabIndia Computer science&Engineering Department Lovely Professional UniversityJalandharPunjabIndia Department of Computer science College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Higher Polytechnic school/Industrial Organization Engineering Universidad Europea del AtlánticoIsabel Torres 2139011SantanderSpain Department of Project Management Universidad Internacional IberoamericanaCampeche24560Mexico Computer science and Engineering Department Deenbandhu Chhotu Ram University of Science and TechnologyMurthalSonipatHaryanaIndia

The rapid expansion of Internet of Things(IoT)devices deploys various sensors in different applications like homes,cities and *** applications depend upon the accuracy of sensor ***,it is necessary to predict faults in the sensor and isolate their cause.A novel primitive technique named fall curve is presented in this paper which characterizes sensor *** technique identifies the faulty sensor and determines the correct working of the *** sources of sensor faults are explained in detail whereas various faults that occurred in sensor nodes available in IoT devices are also presented in tabular *** prediction in digital and analog sensors along with methods of sensor fault prediction are *** are several advantages and disadvantages of sensor fault prediction methods and the fall curve ***,some solutions are provided to overcome the limitations of the fall curve *** this paper,a bibliometric analysis is carried out to visually analyze 63 papers fetched from the scopus database for the past five *** novelty is to predict a fault before its occurrence by looking at the fall *** sensing of current flow in devices is important to prevent a major ***,the fall curves of ACs712 current sensors configured on different devices are drawn for predicting faulty or non-faulty *** analysis result proved that if any of the current sensors gets faulty,then the fall curve will differ and the value will immediately drop to *** evaluation metrics for fault prediction are also described in this *** last,this paper also addresses some possible open research issues which are important to deal with false IoT sensor data.

关键词： Fault identification fault classification IoT sensor nodes analog sensors digital sensors fall curve

Generalised tanh-shaped hyperbolic potential: Klein–Gordon equation's bound state solution

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Communications in Theoretical Physics 2023年第7期75卷 22-32页

作者： v H Badalov s v Badalov Institute for Physical Problems Baku State University1148 BakuAzerbaijan Theoretical Materials Physics Paderborn UniversityD-33098 PaderbornGermany Theoretical PhysicsⅦ University of BayreuthD-95440 BayreuthGermany

The development of potential theory heightens the understanding of fundamental interactions in quantum *** this paper,the bound state solution of the modified radial Klein–Gordon equation is presented for generalised tanh-shaped hyperbolic potential from the Nikiforov–Uvarov *** resulting energy eigenvalues and corresponding radial wave functions are expressed in terms of the Jacobi polynomials for arbitrary l *** is also demonstrated that energy eigenvalues strongly correlate with potential parameters for quantum *** particular cases,the generalised tanh-shaped hyperbolic potential and its derived energy eigenvalues exhibit good agreement with the reported ***,the rovibrational energies are calculated for three representative diatomic molecules,namely H2,HCl and *** lowest excitation energies are in perfect agreement with experimental ***,the potential model is displayed to be a viable candidate for concurrently prescribing numerous quantum systems.

关键词： Klein-Gordon equation hyperbolic potential Nikiforov-Uvarov method diatomic molecules

Mongolian spots:How important are they?

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World Journal of Clinical Cases 2013年第8期1卷 230-232页

作者： divya Gupta Devinder Mohan Thappa Department of skin and sTD JIPMERPuducherry 605006India

Mongolian spots(Ms) are congenital birthmarks seen most commonly over the lumbosacral area. They are bluish-green to black in color and oval to irregular in shape. They are most commonly found in individuals of African or Asian ethnic background. Although these lesions resolve by one to two years of age, widespread, extrasacral and dark colored Ms sometimes persist into adulthood. Aberrant Ms over occiput, temple, mandibular area, shoulders and limbs may be confused with other dermal melanocytoses and bruises secondary to child abuse, thus necessitating documentation at birth. Although traditionally believed to be benign in nature, they have now been shown to co-exist with inborn errors of metabolism, most commonly GM1 gangliosidosis and mucopolysaccharidosis type Ⅰ(Hurler's disease), followed by mucopolysaccharidosis type Ⅱ(Hunter's syndrome), mucolipidosis, Niemann-Pick disease and mannosidosis. They have also been seen to co-exist with various vascular or other pigmented birthmarks like café-au-lait macules. Co-existing Mongolian spots and vascular birthmarks like nevus flammeus, nevus anemicus or nevus spilus is termed as phakomatosis pigmentovascularis. This review focuses on the important associations of Mongolian spots and stresses upon the importance of screening babies with extensive Ms.

关键词： Mongolian spot Inborn errors of metabolism

Amberlyst-15 in PEG：A novel catalytic system for the facile and efficient one-pot synthesis of benzothiazolo-[2,3-b]-quinazolinone derivatives

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science China Chemistry 2012年第10期55卷 2154-2160页

作者： MAZAAHIR Kidwai RITIKA Chauhan divya Bhatnagar Green Chemistry Research Laboratory Department of ChemistryUniversity of Delhi

A simple and convenient approach for the synthesis of tetraheterocyclic benzothiazolo-[2,3-b]-quinazolin-1-ones has been developed utilizing the MCR methodology, which involves the condensation of 2-aminobenzothiazole, cyclic-diketones and various aldehydes using Amberlyst-15 in PEG 400 as an environmentally benign and reusable catalyst system. Environmental benignity, recyclability, cost-effectiveness, easy workup and excellent yields are the major attributes of this one-pot procedure.

关键词： Amberlyst-15 benzothiazolo-[2 3-b]-quinazolinones multi-component reaction reusability PEG (polyethylene glycol) green chemistry