Modern Approaches on Material Science最新文献

{"title":"Effect of Laser Welding Parameters on Porosity of Welds in Cast Magnesium Alloy AM50","authors":"K. Fahlström, J. Blackburn, L. Karlsson, L. Svensson","doi":"10.32474/MAMS.2018.01.000106","DOIUrl":"https://doi.org/10.32474/MAMS.2018.01.000106","url":null,"abstract":"Pores in the weld metal lower the mechanical properties of the weld. It is therefore important to understand the pore formation mechanisms and find procedures that could reduce porosity. This study ...","PeriodicalId":437994,"journal":{"name":"Modern Approaches on Material Science","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128496070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Groups 4 and 15 and Organotin Condensation Polymers for The Treatment of Cancers and Viruses","authors":"C. Carraher, M. Roner, P. Slawek, Francesca Mosca, J. Frank, Lindsey C. Miller","doi":"10.32474/MAMS.2018.01.000103","DOIUrl":"https://doi.org/10.32474/MAMS.2018.01.000103","url":null,"abstract":"This short review describes the use of group 4 metallocenes, group 15 organometallics and organotin polymers in the treatment of human cancer tumors and viruses. These metal-containing polymers show good inhibition of all the main group solid tumors including pancreatic, lung, brain, breast, prostate and colon human cell lines. They also show inhibition of a variety of viruses including zika, herpes and vaccinia viruses. Synthesis of the polymers is rapid employing interfacial polymerization and commercially available reactants. They offer physicians a new class of drugs for the treatment of a variety of cancers and viruses.","PeriodicalId":437994,"journal":{"name":"Modern Approaches on Material Science","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116408086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antibacterial Activity of Citrus Aurantifolia Leaves Extracts Against Some Enteric Bacteria of Public Health Importance","authors":"Abubakar U. Zage, T SaniTajo, Muhammad Ali","doi":"10.32474/MAMS.2018.01.000107","DOIUrl":"https://doi.org/10.32474/MAMS.2018.01.000107","url":null,"abstract":"The study was conducted to determine the phytochemical composition and antibacterial activity of Citrus aurantifolia leaves extracts against clinical isolates of some enteric bacteria of public health importance. The result of phytochemical screening of the leaves extracts shows the presence of alkaloid, glycoside, saponin, tannin, flavonoid, steroids, terpenoid and phenol....","PeriodicalId":437994,"journal":{"name":"Modern Approaches on Material Science","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127745973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Palm Oil Fuel Ash as A Cement Replacement in Concrete","authors":"A. Ash","doi":"10.32474/MAMS.2018.01.000102","DOIUrl":"https://doi.org/10.32474/MAMS.2018.01.000102","url":null,"abstract":"To produce concrete, cement is an essential material that binds together solid bodies but also is the largest producer of carbon dioxide (CO 2 ) emission. Up to 10% of global CO 2 emission comes from cement production thus making the sustainability of concrete a major issue that needs addressing. The processes of producing concrete consume heavily on natural resources such as sand, gravel, water, coal and crushed rock, mining of which damages the environment. It is however possible, that energy and cost efficiency can be achieved by reducing on the amount of clinker, and in its place utilizing partial cement replacements/pozzolans that require less process heating and emit fewer levels of carbon dioxide. This study investigates the effectiveness of agro waste ash by-product Palm Oil Fuel Ash (POFA) as an alternative material to replace Portland cement (OPC). Experiments were carried out by supplementing CEM I cement by weight in concrete mixes with POFA at 2.5%, 5%, 10%, 15% and 20% steps at the point of need, with water to cement ratio of 0.5. Results were compared with a control specimen, which was made with 100% cement. The results showed impressive compressive strength, especially at early age; in fact POFA specimens containing 2.5% and 5% POFA replacement displayed greater early compressive strength in comparison to the control, which is similar in behaviour to concrete containing silica fume which is an established partial cement replacement used in high strength applications. The results showed good repeatability and highlight the potential of POFA as an effective pozzolan which could enhance the sustainability and economic aspect of concrete.","PeriodicalId":437994,"journal":{"name":"Modern Approaches on Material Science","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114554718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prevalence of Staphylococcus Aureus among Children Diagonosed with Acute Diarrhea in Kano, Nigeria","authors":"A. Umar","doi":"10.32474/mams.2019.01.000110","DOIUrl":"https://doi.org/10.32474/mams.2019.01.000110","url":null,"abstract":"The burden of diarrheal disease is most critical in developing countries, facilitated by unsafe water supplies, poor sanitation, and nutritional deficiencies. The research was aimed to study the prevalence of Staphylococcus aureus among children diagnosed with acute diarrhea in Kura General Hospital Kano, Nigeria. Fecal specimens were collected in clean, dry and leak proof sterile bottle from 58 child patients (ranges from 1-5 years) admitted to Kura General Hospital and diagnosed with acute diarrhea from period of March to August 2017. The isolates were isolated and identified using Gram staining, Biochemical test (Catalase, Coagulase and DNase test), Mannitol fermentation and haemolysis test. The result showed that 34 samples out of 58 were positive for S. aureus. Higher incidence was found among males (20 subjects which accounted for 59%) than female with total of 14 subjects accounted for 41%. Highest frequency of diarrhea infection is found among subject with age between 1-2 years and more male (53%) were infected than female (47%). Statistical analysis of the result showed that there is no considerable statistical difference on prevalence of S. aureus among sex group and age categories of the subject at p<0.05. It is recommended that proper environmental sanitation, good personal hygiene and complete immunization against diarrhea disease are recommended.","PeriodicalId":437994,"journal":{"name":"Modern Approaches on Material Science","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126726108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study the Corrosion and Corrosion Protection of Brass Sculpture by Atmospheric Pollutants in Winter Season","authors":"R. Singh","doi":"10.32474/mams.2019.01.000111","DOIUrl":"https://doi.org/10.32474/mams.2019.01.000111","url":null,"abstract":"Brass is an important metalloid which is used in construction of sculptures. It is noticed that sculpture of brass is corroding due to interaction of pollutants. The pollutants develop chemical and electrochemical reaction on the surface of base material. Their concentrations of corrosive pollutants are increased in winter season. The air quality becomes very poor in winter season. Inside sculpture different forms of corrosion are observed like galvanic, pitting, stress, crevice etc. The major components of pollutants are oxides of carbon, oxides of nitrogen, oxides of sulphur, ammonia, ozone and particulates. Among these pollutants oxides of sulphur and ammonia are major corroder of brass. Ammonia is observed moist air to form ammonium hydroxide. It produces chemical reaction with brass metal and form complex compounds like [Zn(NH4)4](OH)2, [Zn(NH4)4]SO4, [Zn(NH4)]CO3, [Cu(NH4)4](OH)2, [Cu(NH4)4]SO4, [Cu(NH4)]CO3 etc. Oxides of sulphur react with moist air to exhibit sulphurous and sulphuric acids. They interact with brass to develop corrosion cell zinc metal and it is oxidized into Zn2+ ions and these ions are active to humidity and carbon dioxide to yield Zn(OH)2.ZnCO3.2H2O. Copper is converted into Cu2+ and it reacts with moist air and carbon dioxide to produce Cu(OH)2.Cu(CO3)2 and these complex compound detached on the surface of brass metal by rain water. These pollutants change their physical, chemical and mechanical properties and they also tarnish their facial appearance. Brass’ sculpture is affected by uniform corrosion. This type of corrosion can be control by nanocoating and electrospray techniques. For this work (6Z)-5,8-dihydrazono5,8-dibenzo[a,c][8]annulene and TiO2 are used as nanocoating and electrospray materials. The corrosion rate of material was determined by gravimetric and potentiostat technique. The nanocoating and electrospray compounds are formed a composite layer on surface of base metal. The formation of composite layer is analyzed by thermal parameters like activation energy, heat of adsorption, free energy, enthalpy and entropy. These thermal parameters were calculated by Arrhenius, Langmuir isotherm and transition state equations. Thermal parameters results are depicted that both materials are adhered with sculpture through chemical bonding. The surface coverage area and coating efficiency indicates that nanocoating and electrospray are produced a protective barrier in ammonia and sulphur dioxide atmosphere.","PeriodicalId":437994,"journal":{"name":"Modern Approaches on Material Science","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133833168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}