Pub Date : 2016-07-05DOI: 10.4236/WJNSE.2016.63012
R. Seoudi, F. Al-Marhaby
In this work, different sizes of gold nanoparticles were synthesized at room temperature by using trisodium citrate as a surfactant stabilizing agent and sodium borohydride as a reducing agent. Transmission Electron Microscopy (TEM) confirmed that the samples were synthesized in spherical shapes with three different particle sizes: 4 nm, 7 nm and 11 nm. Ultraviolet-visible spectra measurements were used to analyze the way that surface plasmon bands were affected by the different particles sizes. The effect of sphere size on photocatalytic reduction of 4-Nitrophenol was then studied and the rate constant of the reduction was calculated to be 0.014 s-1, 0.0091 s-1 and 0.003 s-1 for particles sizes of 4 nm, 7 nm and 11 nm, respectively. The results obtained indicated that small particles were more active in catalytic reduction due to their high surface energy.
{"title":"Synthesis, Characterization and Photocatalytic Application of Different Sizes of Gold Nanoparticles on 4-Nitrophenol","authors":"R. Seoudi, F. Al-Marhaby","doi":"10.4236/WJNSE.2016.63012","DOIUrl":"https://doi.org/10.4236/WJNSE.2016.63012","url":null,"abstract":"In this work, different sizes of gold nanoparticles were synthesized at room temperature by using trisodium citrate as a surfactant stabilizing agent and sodium borohydride as a reducing agent. Transmission Electron Microscopy (TEM) confirmed that the samples were synthesized in spherical shapes with three different particle sizes: 4 nm, 7 nm and 11 nm. Ultraviolet-visible spectra measurements were used to analyze the way that surface plasmon bands were affected by the different particles sizes. The effect of sphere size on photocatalytic reduction of 4-Nitrophenol was then studied and the rate constant of the reduction was calculated to be 0.014 s-1, 0.0091 s-1 and 0.003 s-1 for particles sizes of 4 nm, 7 nm and 11 nm, respectively. The results obtained indicated that small particles were more active in catalytic reduction due to their high surface energy.","PeriodicalId":66816,"journal":{"name":"纳米科学与工程(英文)","volume":"845 1","pages":"120-128"},"PeriodicalIF":0.0,"publicationDate":"2016-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70881980","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}
Pub Date : 2016-07-05DOI: 10.4236/WJNSE.2016.63011
Mohamed Ahmed, M. El-Shennawy, Yousef M. Althomali, A. Omar
The aim of this study is to clarify the effect of different concentrations of titanium dioxide nanoparticles (Nps) on the properties of two types of heat polymerized acrylic resin. The tested parameters were flexural strength, impact strength, and microhardness. The two types of acrylic resin used in this study were conventional unmodified (Implacryl, Vertex) and high impact heat polymerized acrylic resin (Vertex-Dental, Netherlands). Both types of acrylic resin were modified by using 1% and 5% TiO2 Nps powder. Specimen’s dimensions were prepared according to the American Dental Association Specification No. 12. Three types of specimens were prepared: 1) flexural strength specimens 50 mm × 10 (±0.2) mm × 3 (±0.2) mm, 2) impact strength test specimens 60 mm × 6.0 mm × 4.0 mm, 3) microhardnesss specimens 25 mm × 10 mm × 3 (±0.2) mm. For each test 6 groups were prepared (each group containing 5 samples). Thirty specimens were prepared in each of the three tests, amounting to a total number of 90 specimens. Mechanical properties such as flexural strength (FS), impact strength and microhardness of the above mentioned specimens were determined using universal testing machine, Izod pendulum impact testing machine and Vickers microhardness tester, respectively. ISO Specification No. 1567 was followed in microhardness test. The data was collected and statistically analyzed. Flexural strength considerably decreased by increasing TiO2 concentration in both types of acrylic resin. Impact strength of the conventional acrylic resin modified by 1% of additives significantly increased. The microhardness is significantly increased by addition of 5% of TiO2 Nps. The Incorporation of TiO2 nanoparticles into acrylic resins can adversely affect its flexural strength. Meanwhile, the impact strength can be modified by small percentage of additives (abt. 1%). This effect is directly correlated with the concentration of nanoparticles. On the other hand, concentrations of TiO2 Nps (abt. 5%) positively affect the microhardness of both types of acrylic resin used in the present study.
本研究的目的是阐明不同浓度的二氧化钛纳米颗粒(Nps)对两种热聚合丙烯酸树脂性能的影响。测试参数为抗弯强度、冲击强度和显微硬度。本研究中使用的两种丙烯酸树脂是常规的未改性丙烯酸树脂(Implacryl, Vertex)和高冲击热聚合丙烯酸树脂(Vertex- dental,荷兰)。分别用1%和5%的TiO2 Nps粉末对两种丙烯酸树脂进行改性。样品的尺寸根据美国牙科协会规范第12号制备。制备三种试样:1)抗弯强度试样50 mm × 10(±0.2)mm × 3(±0.2)mm, 2)冲击强度试样60 mm × 6.0 mm × 4.0 mm, 3)显微硬度试样25 mm × 10 mm × 3(±0.2)mm,每组制备6组(每组5个试样)。三次试验各制备30个试样,共制备90个试样。采用万能试验机、伊佐德摆锤式冲击试验机和维氏显微硬度计分别测定上述试样的抗弯强度(FS)、冲击强度和显微硬度等力学性能。显微硬度试验按照ISO 1567规范进行。收集数据并进行统计分析。随着TiO2浓度的增加,两种类型的丙烯酸树脂的抗弯强度显著降低。常规丙烯酸树脂经1%的添加剂改性后,冲击强度明显提高。添加5%的TiO2 Nps可显著提高材料的显微硬度。二氧化钛纳米颗粒掺入丙烯酸树脂中会对丙烯酸树脂的抗弯强度产生不利影响。同时,加入少量的添加剂(约1%)也能提高材料的冲击强度。这种效应与纳米颗粒的浓度直接相关。另一方面,TiO2 Nps的浓度(约5%)正影响本研究中使用的两种丙烯酸树脂的显微硬度。
{"title":"Effect of Titanium Dioxide Nano Particles Incorporation on Mechanical and Physical Properties on Two Different Types of Acrylic Resin Denture Base","authors":"Mohamed Ahmed, M. El-Shennawy, Yousef M. Althomali, A. Omar","doi":"10.4236/WJNSE.2016.63011","DOIUrl":"https://doi.org/10.4236/WJNSE.2016.63011","url":null,"abstract":"The aim of this study is to clarify the effect of different concentrations of titanium dioxide nanoparticles (Nps) on the properties of two types of heat polymerized acrylic resin. The tested parameters were flexural strength, impact strength, and microhardness. The two types of acrylic resin used in this study were conventional unmodified (Implacryl, Vertex) and high impact heat polymerized acrylic resin (Vertex-Dental, Netherlands). Both types of acrylic resin were modified by using 1% and 5% TiO2 Nps powder. Specimen’s dimensions were prepared according to the American Dental Association Specification No. 12. Three types of specimens were prepared: 1) flexural strength specimens 50 mm × 10 (±0.2) mm × 3 (±0.2) mm, 2) impact strength test specimens 60 mm × 6.0 mm × 4.0 mm, 3) microhardnesss specimens 25 mm × 10 mm × 3 (±0.2) mm. For each test 6 groups were prepared (each group containing 5 samples). Thirty specimens were prepared in each of the three tests, amounting to a total number of 90 specimens. Mechanical properties such as flexural strength (FS), impact strength and microhardness of the above mentioned specimens were determined using universal testing machine, Izod pendulum impact testing machine and Vickers microhardness tester, respectively. ISO Specification No. 1567 was followed in microhardness test. The data was collected and statistically analyzed. Flexural strength considerably decreased by increasing TiO2 concentration in both types of acrylic resin. Impact strength of the conventional acrylic resin modified by 1% of additives significantly increased. The microhardness is significantly increased by addition of 5% of TiO2 Nps. The Incorporation of TiO2 nanoparticles into acrylic resins can adversely affect its flexural strength. Meanwhile, the impact strength can be modified by small percentage of additives (abt. 1%). This effect is directly correlated with the concentration of nanoparticles. On the other hand, concentrations of TiO2 Nps (abt. 5%) positively affect the microhardness of both types of acrylic resin used in the present study.","PeriodicalId":66816,"journal":{"name":"纳米科学与工程(英文)","volume":"06 1","pages":"111-119"},"PeriodicalIF":0.0,"publicationDate":"2016-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70881760","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}
Pub Date : 2016-04-15DOI: 10.4236/WJNSE.2016.62006
Y. Tuleushev, V. Volodin, Е. А. Zhakanbaev, V. Lisitsin, A. Migunova, A. Suleymenova
Ion-plasma sputtering and codeposition of ultrafine Ta and Cd particles on a moving substrate were used to prepare the solid solutions, in particular, the alloys with up to 66.2 at.% Cd in the form of coatings. In vacuum heat treatment cadmium evaporates at 700°C from cadmium based solid solutions resulting in formation of a porous tantalum with a highly developed surface. The prepared tantalum-based materials assume the technological application of the investigation results.
{"title":"Technology of Porous Tantalum Production","authors":"Y. Tuleushev, V. Volodin, Е. А. Zhakanbaev, V. Lisitsin, A. Migunova, A. Suleymenova","doi":"10.4236/WJNSE.2016.62006","DOIUrl":"https://doi.org/10.4236/WJNSE.2016.62006","url":null,"abstract":"Ion-plasma sputtering and codeposition of ultrafine Ta and Cd particles on a moving substrate were used to prepare the solid solutions, in particular, the alloys with up to 66.2 at.% Cd in the form of coatings. In vacuum heat treatment cadmium evaporates at 700°C from cadmium based solid solutions resulting in formation of a porous tantalum with a highly developed surface. The prepared tantalum-based materials assume the technological application of the investigation results.","PeriodicalId":66816,"journal":{"name":"纳米科学与工程(英文)","volume":"167 1","pages":"51-57"},"PeriodicalIF":0.0,"publicationDate":"2016-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70881116","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}
Pub Date : 2016-04-15DOI: 10.4236/WJNSE.2016.62005
Lefayet Sultan Lipol, M. Rahman
Electro-spinning is a very modern process which can be used in various purposes. We did this experimental work at Swerea IVF in Sweden during M. Sc in Textile Technology programme at University of Bor?s. We should especially thank our supervisor—Anna Thorvaldsson and course teacher—Ioannis S. Chronakis. In this report, we have tried to explain the basic manufacturing techniques of the electrospun nanofiber by the electro-spinning, how one can characterize it by SEM (Scanning Electron Microscopy) and its various applications in the practical field, e.g wound healing, Tissue Engineering Scaffold. The experimental work helped us a lot to gather sufficient knowledge about the electro-spinning process which we wanted to share with all.
电纺丝是一种非常现代的工艺,可用于各种用途。我们在瑞典博尔斯大学纺织技术硕士项目期间在斯韦厄试管婴儿中心进行了这项实验工作。我们要特别感谢我们的导师anna Thorvaldsson和课程老师ioannis S. Chronakis。本文介绍了电纺丝纳米纤维的基本制造技术、如何用扫描电子显微镜对其进行表征,以及电纺丝纳米纤维在伤口愈合、组织工程支架等实际领域的应用。实验工作帮助我们收集了足够的关于电纺丝过程的知识,我们想与大家分享。
{"title":"Electrospinning and Electrospun Nanofibers","authors":"Lefayet Sultan Lipol, M. Rahman","doi":"10.4236/WJNSE.2016.62005","DOIUrl":"https://doi.org/10.4236/WJNSE.2016.62005","url":null,"abstract":"Electro-spinning is a very modern process which can be used in various purposes. We did this experimental work at Swerea IVF in Sweden during M. Sc in Textile Technology programme at University of Bor?s. We should especially thank our supervisor—Anna Thorvaldsson and course teacher—Ioannis S. Chronakis. In this report, we have tried to explain the basic manufacturing techniques of the electrospun nanofiber by the electro-spinning, how one can characterize it by SEM (Scanning Electron Microscopy) and its various applications in the practical field, e.g wound healing, Tissue Engineering Scaffold. The experimental work helped us a lot to gather sufficient knowledge about the electro-spinning process which we wanted to share with all.","PeriodicalId":66816,"journal":{"name":"纳米科学与工程(英文)","volume":"6 1","pages":"45-50"},"PeriodicalIF":0.0,"publicationDate":"2016-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70881064","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}
Pub Date : 2016-04-15DOI: 10.4236/WJNSE.2016.62009
M. Zaydan, Naoufal Yadil, Z. Boulahia, Abderrahim Wakif, R. Sehaqui
In the present work, we numerically study the laminar natural convection of a nanofluid confined in a square cavity. The vertical walls are assumed to be insulated, non-conducting, and impermeable to mass transfer. The horizontal walls are differentially heated, and the low is maintained at hot condition (sinusoidal) when the high one is cold. The objective of this work is to develop a new height accurate method for solving heat transfer equations. The new method is a Fourth Order Compact (F.O.C). This work aims to show the interest of the method and understand the effect of the presence of nanofluids in closed square systems on the natural convection mechanism. The numerical simulations are performed for Prandtl number ( ), the Rayleigh numbers varying between and for different volume fractions varies between 0% and 10% for the nanofluid (water + Cu).
{"title":"Fourth-Order Compact Formulation for the Resolution of Heat Transfer in Natural Convection of Water-Cu Nanofluid in a Square Cavity with a Sinusoidal Boundary Thermal Condition","authors":"M. Zaydan, Naoufal Yadil, Z. Boulahia, Abderrahim Wakif, R. Sehaqui","doi":"10.4236/WJNSE.2016.62009","DOIUrl":"https://doi.org/10.4236/WJNSE.2016.62009","url":null,"abstract":"In the present work, we numerically study the laminar natural convection of a nanofluid confined in a square cavity. The vertical walls are assumed to be insulated, non-conducting, and impermeable to mass transfer. The horizontal walls are differentially heated, and the low is maintained at hot condition (sinusoidal) when the high one is cold. The objective of this work is to develop a new height accurate method for solving heat transfer equations. The new method is a Fourth Order Compact (F.O.C). This work aims to show the interest of the method and understand the effect of the presence of nanofluids in closed square systems on the natural convection mechanism. The numerical simulations are performed for Prandtl number ( ), the Rayleigh numbers varying between and for different volume fractions varies between 0% and 10% for the nanofluid (water + Cu).","PeriodicalId":66816,"journal":{"name":"纳米科学与工程(英文)","volume":"06 1","pages":"70-89"},"PeriodicalIF":0.0,"publicationDate":"2016-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70881282","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}
Pub Date : 2016-04-15DOI: 10.4236/WJNSE.2016.62007
S. Al-Assafi, Nils de Bruijn, A. Al-Jumaily
Growing demand for high-performance materials is driving the development of composites with nano material reinforcement. The use of nano reinforcement can provide a distinct advantage due to high surface area of the material. There are still many challenges in achieving the full potential of nanocomposites. In this paper, we investigate the performance of epoxy nanocomposites reinforced with short polymethyl methacrylate (PMMA) nanofibers. PMMA nanofibers were chopped and mixed with the epoxy resin and then the mixture was poured into a mould. Samples were cut to an appropriate size after cure and mechanical testing was carried out. Tensile and flexural strength and modulus were evaluated for samples with various fiber volume fractions to determine changes in mechanical performance. Also Scanning Electron Microscopy was utilized to investigate fracture surface and fiber-matrix interface. Results indicated that mechanical performance dropped as volume fraction of fibers increased, namely poor fiber-matrix adhesion and presence of porosity resulted in deterioration in strength and modulus. Further research is required to develop fiber coating system to enhance performance of the nanocomposite by improving fiber-matrix adhesion and fiber wet-out.
{"title":"Processing and Characterization of PMMA Nanofiber Reinforced Epoxy Composites","authors":"S. Al-Assafi, Nils de Bruijn, A. Al-Jumaily","doi":"10.4236/WJNSE.2016.62007","DOIUrl":"https://doi.org/10.4236/WJNSE.2016.62007","url":null,"abstract":"Growing demand for high-performance materials is driving the development of composites with nano material reinforcement. The use of nano reinforcement can provide a distinct advantage due to high surface area of the material. There are still many challenges in achieving the full potential of nanocomposites. In this paper, we investigate the performance of epoxy nanocomposites reinforced with short polymethyl methacrylate (PMMA) nanofibers. PMMA nanofibers were chopped and mixed with the epoxy resin and then the mixture was poured into a mould. Samples were cut to an appropriate size after cure and mechanical testing was carried out. Tensile and flexural strength and modulus were evaluated for samples with various fiber volume fractions to determine changes in mechanical performance. Also Scanning Electron Microscopy was utilized to investigate fracture surface and fiber-matrix interface. Results indicated that mechanical performance dropped as volume fraction of fibers increased, namely poor fiber-matrix adhesion and presence of porosity resulted in deterioration in strength and modulus. Further research is required to develop fiber coating system to enhance performance of the nanocomposite by improving fiber-matrix adhesion and fiber wet-out.","PeriodicalId":66816,"journal":{"name":"纳米科学与工程(英文)","volume":"06 1","pages":"58-63"},"PeriodicalIF":0.0,"publicationDate":"2016-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70881176","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}
Pub Date : 2016-04-15DOI: 10.4236/WJNSE.2016.62008
Mohamed I. Ebrahim, Mohamed Ahmed, Nayef H. Felemban
Adhesive layer is an essential part of tooth colored restorations which play an important role in decreasing the microleakage between the tooth and restoration material after polymerization shrinkage. The purpose of this study was to evaluate the effect of deferent adhesive system of bonding agent on microleakage of nanocomposite resin in class II cavities. Two different types of adhesive systems: universal adhesive (ExciTE) and a newly developed adhesive (Nano-Bond) and one type of light-cured resin restorative material (nanocomposite resin) were used in this study. These adhesives were applied to prepared tooth cavities by either manufactures’ instructions or by an experimental method (single or double application). Nanocomposite resin was then placed and light-cured for 40 seconds. Teeth were subjected to 500 thermal cycles between 5d microleakage was observed microscopically. The data were analyzed by a two-way ANOVA. For comparison between groups, Tukey’s post-hoc test was used. Nanoparticles reinforced adhesive system shows low microleakage in compare with universal adhesive system, and application of two adhesive layers also can decrease the microleakage. The ability of stress absorption by adhesive layer after polymerization shrinkage of restoration material will reduce the microleakage.
{"title":"Effect of Nanoparticles Reinforced Adhesive Layers on Microleakage of Tooth Restorations","authors":"Mohamed I. Ebrahim, Mohamed Ahmed, Nayef H. Felemban","doi":"10.4236/WJNSE.2016.62008","DOIUrl":"https://doi.org/10.4236/WJNSE.2016.62008","url":null,"abstract":"Adhesive layer is an essential part of tooth colored restorations which play an important role in decreasing the microleakage between the tooth and restoration material after polymerization shrinkage. The purpose of this study was to evaluate the effect of deferent adhesive system of bonding agent on microleakage of nanocomposite resin in class II cavities. Two different types of adhesive systems: universal adhesive (ExciTE) and a newly developed adhesive (Nano-Bond) and one type of light-cured resin restorative material (nanocomposite resin) were used in this study. These adhesives were applied to prepared tooth cavities by either manufactures’ instructions or by an experimental method (single or double application). Nanocomposite resin was then placed and light-cured for 40 seconds. Teeth were subjected to 500 thermal cycles between 5d microleakage was observed microscopically. The data were analyzed by a two-way ANOVA. For comparison between groups, Tukey’s post-hoc test was used. Nanoparticles reinforced adhesive system shows low microleakage in compare with universal adhesive system, and application of two adhesive layers also can decrease the microleakage. The ability of stress absorption by adhesive layer after polymerization shrinkage of restoration material will reduce the microleakage.","PeriodicalId":66816,"journal":{"name":"纳米科学与工程(英文)","volume":"06 1","pages":"64-69"},"PeriodicalIF":0.0,"publicationDate":"2016-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70881223","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}
Pub Date : 2016-04-15DOI: 10.4236/WJNSE.2016.62010
T. A. Sironmani
Nanotechnology has shown significant promise in development of drugs and drug delivery systems that can overcome all limitations and address urgent needs to improve efficacy of diagnosis and therapy of various diseases including cancer. The functionalization with neem compounds as synthesis and capping agent had shown very high anticancer activities against Gastric cancer cells in vitro. The biochemical factors like albumin, glucose, and DNA concentrations were modulated along with Protease inhibitor and Catalase activates, the various cancer specific proteins like p53, GRD 70 - 78 kDa and other proteins of sizes 35 - 40 kDa corresponding to H+K+ATPase protein etc. The apoptic activity and antiproliferative activity were demonstrated with Gastric cancer cells in vitro.
{"title":"Therapeutic Potential of Neem Synthesized Silver Nanoparticles on Human Gastric Cancer Cells in Vitro","authors":"T. A. Sironmani","doi":"10.4236/WJNSE.2016.62010","DOIUrl":"https://doi.org/10.4236/WJNSE.2016.62010","url":null,"abstract":"Nanotechnology has shown significant promise in development of drugs and drug delivery systems that can overcome all limitations and address urgent needs to improve efficacy of diagnosis and therapy of various diseases including cancer. The functionalization with neem compounds as synthesis and capping agent had shown very high anticancer activities against Gastric cancer cells in vitro. The biochemical factors like albumin, glucose, and DNA concentrations were modulated along with Protease inhibitor and Catalase activates, the various cancer specific proteins like p53, GRD 70 - 78 kDa and other proteins of sizes 35 - 40 kDa corresponding to H+K+ATPase protein etc. The apoptic activity and antiproliferative activity were demonstrated with Gastric cancer cells in vitro.","PeriodicalId":66816,"journal":{"name":"纳米科学与工程(英文)","volume":"06 1","pages":"90-110"},"PeriodicalIF":0.0,"publicationDate":"2016-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70881713","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}
Pub Date : 2016-01-15DOI: 10.4236/WJNSE.2016.61004
V. Srinivas, A. Raghavender, K. Kumar
Bi1-xBaxFeO3 (0 ≤ x ≤ 0.3) nanopowders were synthesized using sol-gel technique. The structural and magnetic properties were investigated using X-ray diffraction, SEM and VSM. As Ba2+ doping concentration was increased, the structure of the samples changed from rhombohedral to tetragonal or monoclinic. The structural change might be an important factor for achieving the ferroelectric properties in this material. The lattice parameters were observed to increase with increase in Ba2+ concentration. All the M-H loops showed the ferromagnetic behavior. Magnetization was observed to enhance with increase in Ba concentration. The enhancement in the magnetization due to Ba2+ doping may be due to the replacement of Bi3+ ions by Ba2+ which might have resulted in the suppression of spiral spin structure.
{"title":"Effect of Ba Substitution on the Structural and Magnetic Properties of BiFeO 3","authors":"V. Srinivas, A. Raghavender, K. Kumar","doi":"10.4236/WJNSE.2016.61004","DOIUrl":"https://doi.org/10.4236/WJNSE.2016.61004","url":null,"abstract":"Bi1-xBaxFeO3 (0 ≤ x ≤ 0.3) nanopowders were synthesized using sol-gel technique. The structural and magnetic properties were investigated using X-ray diffraction, SEM and VSM. As Ba2+ doping concentration was increased, the structure of the samples changed from rhombohedral to tetragonal or monoclinic. The structural change might be an important factor for achieving the ferroelectric properties in this material. The lattice parameters were observed to increase with increase in Ba2+ concentration. All the M-H loops showed the ferromagnetic behavior. Magnetization was observed to enhance with increase in Ba concentration. The enhancement in the magnetization due to Ba2+ doping may be due to the replacement of Bi3+ ions by Ba2+ which might have resulted in the suppression of spiral spin structure.","PeriodicalId":66816,"journal":{"name":"纳米科学与工程(英文)","volume":"31 1","pages":"38-44"},"PeriodicalIF":0.0,"publicationDate":"2016-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70881433","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}
Pub Date : 2016-01-15DOI: 10.4236/WJNSE.2016.61001
R. Thirunakaran, Gil Hwan Lew, W. Yoon
LiMn2O4 and LiCuxCryMn2-x-yO4 (x = 0.50; y = 0.05 - 0.50) powders have been synthesized via sol-gel method for the first time using Myristic acid as chelating agent. The synthesized samples have been taken to physical and electrochemical characterization such as thermo gravimetric analysis (TG/DTA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and electrochemical characterization viz., electrochemical galvanostatic cycling studies, electrochemical impedance spectroscopy (EIS) and differential capacity curves (dQ/dE). XRD patterns of LiMn2O4 and LiCuxCryMn2-x-yO4 confirm high degree of crystallinity with good phase purity. FESEM image of undoped pristine spinel lucidly depicts cauliflower morphology with good agglomerated particle size of 50 nm while 0.5-Cu doped samples depict the pebbles morphology. TEM images of the spinel LiMn2O4 and LiCu0.5Cr0.05Mn1.45O4 authenticate that all the synthesized particles via sol-gel method are nano-sized (100 nm) with spherical surface and cloudy particles morphology. The LiMn2O4 samples calcined at 850℃ deliver the high discharge capacity of 130 mA·h/g with cathodic efficiency of 88% corresponds to 94% columbic efficiency in the first cycle. Among all four compositions studied, LiCu0.5Cr0.05Mn1.45O4 delivers 124 mA·h/g during the first cycle and shows stable performance with a low capacity fade of 1.1 mA·h/g cycle over the investigated 10 cycles.
{"title":"Sol-Gel Synthesis Using Novel Chelating Agent and Electrochemical Characterization of Binary Doped LiMn 2 O 4 Spinel as Cathode Material for Lithium Rechargeable Batteries","authors":"R. Thirunakaran, Gil Hwan Lew, W. Yoon","doi":"10.4236/WJNSE.2016.61001","DOIUrl":"https://doi.org/10.4236/WJNSE.2016.61001","url":null,"abstract":"LiMn2O4 and LiCuxCryMn2-x-yO4 (x = 0.50; y = 0.05 - 0.50) powders have been synthesized via sol-gel method for the first time using Myristic acid as chelating agent. The synthesized samples have been taken to physical and electrochemical characterization such as thermo gravimetric analysis (TG/DTA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and electrochemical characterization viz., electrochemical galvanostatic cycling studies, electrochemical impedance spectroscopy (EIS) and differential capacity curves (dQ/dE). XRD patterns of LiMn2O4 and LiCuxCryMn2-x-yO4 confirm high degree of crystallinity with good phase purity. FESEM image of undoped pristine spinel lucidly depicts cauliflower morphology with good agglomerated particle size of 50 nm while 0.5-Cu doped samples depict the pebbles morphology. TEM images of the spinel LiMn2O4 and LiCu0.5Cr0.05Mn1.45O4 authenticate that all the synthesized particles via sol-gel method are nano-sized (100 nm) with spherical surface and cloudy particles morphology. The LiMn2O4 samples calcined at 850℃ deliver the high discharge capacity of 130 mA·h/g with cathodic efficiency of 88% corresponds to 94% columbic efficiency in the first cycle. Among all four compositions studied, LiCu0.5Cr0.05Mn1.45O4 delivers 124 mA·h/g during the first cycle and shows stable performance with a low capacity fade of 1.1 mA·h/g cycle over the investigated 10 cycles.","PeriodicalId":66816,"journal":{"name":"纳米科学与工程(英文)","volume":"6 1","pages":"1-19"},"PeriodicalIF":0.0,"publicationDate":"2016-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70879642","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}