An Experimental Investigation on Workability and Bleeding Behaviors of Cement Pastes Doped with Nano Titanium Oxide (n-TiO 2) Nanoparticles and FlyAsh

In this study,the workability of cement-based grouts containing n-TiO 2 nanoparticles and fly ash has been investigated experimentally.Several characteristic quantities(including,but not limited to,the marsh cone flow time,the mini slump spreading diameter and the plate cohesion meter value)have been measured for different percentages of these additives.The use of fly ash as a mineral additive has been found to result in improvements in terms of workability behavior as expected.Moreover,if nano titanium oxide is also used,an improvement can be obtained regarding the bleeding values for the cement-based grout mixes.Using such experimental data,a multi-layer perceptron artificial neural network model has been developed(5 neurons in the hidden layer of the network model have been developed using a total of 42 experimental data).70%of the data employed in this model have been used for training,15%for validation and 15%for the test phase.The results demonstrate that the artificial neural network model can predict Marsh cone flow time,mini slump spreading diameter and plate cohesion meter values with an average error of 0.15%.

Efficiency and Mechanism of Phosphorus Removal by Coagulation of Iron-manganese Composited Oxide

Iron-manganese composited oxide（FeMnO） was prepared with potassium permanganate and ferrous salt. Interface performance, charge property and structure topography of the FeMnO were investigated. Coagulation efficiency and pollution removal mechanism of the FeMnO were approached. Results show that the main compositions of the FeMnO are δ-manganese dioxide and ferric hydroxide. The specific surface area is about 146.22 m^2/g. The FeMnO contains rich hydroxyl with extremely strong adsorption action and chemical adsorption activity. The zero charge point of the oxide in pure water is about 8.0 of pH value. Under neutral pH value conditions, the FeMnO particle surface carried positive charges. The FeMnO particles are quasi-spherical micro-particles with irregular sizes adjoined each other to form net construction. Phosphorus removal efficiency of the FeMnO is remarkable, the total dissoluble phosphorus of settled water can be reduced below detecting level（0.3 μtg/L） at a FeMnO dosage of 6 mg/L, and total phosphorus below detecting level at a FeMnO dosage of 10 mg/L, for water samples containing total phos- phorus of 1281.70 μg/L and total dissoluble phosphorus of 1187.91 μtg/L. The mechanism of effective coagulation for phosphorus removal is combined results of multiple actions of adsorption, charge neutralization, adsorption/bridging and so on.

Incorporation of Nano-Zinc Oxide in Lamellar Zirconium Phosphate: Synthesis and Characterization

In order to provide ultraviolet barrier, antifungal and antibacterial properties, nano-zinc oxide (ZnO) was added to lamellar zirconium phosphate (ZrP). The phosphate was synthesized via reaction of zirconium oxychloride octahydrate and phosphoric acid following its chemical modification with Jeffamine and nano-ZnO. Diffractometric, morphological, thermal, structural and relaxometric evaluations were conducted. Fourier transform infrared spectroscopy (FTIR) revealed increase of the area between 4000 - 3000 cm-1 due to the formation of ionic specie PO? +NH3-[C-(H)(CH3)-CH2-O-(C-(H)(CH3)-CH2-O)8-(CH2-CH2-O-CH3)] and nano-ZnO particles. Wide-angle X-ray diffraction indicated that intercalation of Jeffamine was successful. Thermogravimetry confirmed that nano-ZnO particle forced the expulsion of Jeffamine outside ZrP galleries. Scanning electron microscopy evidenced the Jeffamine intercalation and sample heterogeneity. Hydrogen molecular relaxation indicated the increase of molecular rigidity owing to the formation of ionic specie and the addition of nano-ZnO particles. It was postulated that a multifunctional and miscellaneous material constituted by as prepared ZrP, some delaminated ZrP platelets and nano-ZnO particles was achieved. The material has potential for usage as filler in polymeric composites.

抗菌PP/Rnano-ZnO复合材料的制备及性能研究

以棒状纳米氧化锌(Rnano-ZnO)为抗菌剂、聚丙烯(PP)为基材,采用熔融共混法在双螺杆挤出机中制备了抗菌PP/Rnano-ZnO复合材料。测试了复合材料的抗菌性能,通过DSC法研究了抗菌PP/Rnano-ZnO复合材料中Rnano-ZnO质量分数对结晶性能的影响,采用SEM分析了复合材料冲击断面的微观形貌,采用万能电子拉伸机测试了复合材料的力学性能。结果表明,抗菌PP/Rnano-ZnO复合材料中随着Rnano-ZnO的加入,结晶温度提高了1.81℃,相对结晶度提高了5.03%,冲击强度提高了47.83%,拉伸强度提高了20.96%和断裂伸长率提高了4790%;当抗菌PP/Rnano-ZnO复合材料中Rnano-ZnO质量分数为6.0%时,其力学性能、对大肠杆菌和金黄色葡萄球菌的抗菌效果最佳。

Recent advances and influencing parameters in developing electrode materials for symmetrical solid oxide fuel cells

This article delivers a robust overview of potential electrode materials for use in symmetrical solid oxide fuel cells(S-SOFCs),a relatively new SOFC technology.To this end,this article provides a comprehensive review of recent advances and progress in electrode materials for S-SOFC,discussing both the selection of materials and the challenges that come with making that choice.This article discussed the relevant factors involved in developing electrodes with nano/microstructure.Nanocomposites,e.g.,non-cobalt and lithiated materials,are only a few of the electrode types now being researched.Furthermore,the phase structure and microstructure of the produced materials are heavily influenced by the synthesis procedure.Insights into the possibilities and difficulties of the material are discussed.To achieve the desired microstructural features,this article focuses on a synthesis technique that is either the most recent or a better iteration of an existing process.The portion of this analysis that addresses the risks associated with manufacturing and the challenges posed by materials when fabricating S-SOFCs is the most critical.This article also provides important and useful recommendations for the strategic design of electrode materials researchers.

Effects of acetic acid on microstructure and electrochemical properties of nano cerium oxide films coated on AA7020-T6 aluminum alloy

Nano cerium oxide films were applied on AA7020-T6 aluminum alloy and the effects of acetic acid concentration on the microstructure and electrochemical properties of the coated samples were investigated by using scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and potentiodynamic polarization methods. It has been found that by increasing the acetic acid/CeCl3·7H2O molar ratio, high uniform and crack-free films with well-developed grains were obtained and grain sizes of the films decreased. Elimination of cracks and decreasing grain size of the nano cerium oxide films caused corrosion resistance to increase.

Effect of nano-oxide layers on the magnetoresistance of ultrathin permalloy films

Ta/NiFe/Ta ultrathin films with and without nano-oxide layers （NOLs） were prepared by magnetron sputtering followed by a vacuum annealing process. The influence of NOLs on the magnetoresistance （MR） ratio of ultrathin permalloy films was studied. The results show that the influence of grain size and textures on the MR ratio becomes weak when the thickness of the NiFe layer is below 15 nm. A higher MR ratio was observed for the thinner （〈 15 nm） NiFe film with NOLs. The MR ratio of a 10 nm NiFe film can be remarkably enhanced by NOLs. The enhanced MR ratio for these ultrathin films can be attributed to the enhanced specular reflection of conduction electrons.

Effect of Nano - Titanium Dioxide with Different Antibiotics against Methicillin-Resistant Staphylococcus Aureus

The different investigation has been carried out on the biological activities of titanium dioxide nanoparticle but the effect of this nano product on the antibacterial activity of different antibiotics has not been yet demonstrated. In this study the nano size TiO2 is synthesized using citric acid and alpha dextrose and the enhancement effect of TiO2 nanoparticle on the antibacterial activity of different antibiotics was evaluated against Methicillin-resistant Staphylococcus aureus (MRSA). During the present study, different concentrations of nano-scale TiO2 were tested to find out the best concentration that can have the most effective antibacterial property against the MRSA culture. Disk diffusion method was used to determine the antibacterial activity of these antibiotics in the absence and presence of sub inhibitory concentration of TiO2 nano particle. A clinical isolate of MRSA, isolated from Intensive Care Unit (ICU) was used as test strain. In the presence of sub-inhibitory concentration of TiO2 nanoparticle (20 μg/disc) the antibacterial activities of all antibiotics have been increased against test strain with minimum 2 mm to maximum 10mm. The highest increase in inhibitory zone for MRSA was observed against pencillin G and amikacin (each 10 mm). Conversely, in case of nalidixic acid, TiO2 nanoparticle showed a Synergic effect on the antibacterial activity of this antibiotic against test strain. These results signify that the TiO2 nanoparticle potentate the antimicrobial action of beta lactums, cephalosporins, aminoglycosides, glycopeptides, macrolids and lincosamides, tetracycline a possible utilization of nano compound in combination effect against MRSA.

Mechanochemical Reaction of Lanthanum Carbonate with Sodium Hydroxide and Preparation of Lanthanum Oxide Nanoparticle

The preparation of nano sized La 2O 3 powder by mechanochemical reaction of lanthanum carbonate with sodium hydroxide and subsequent heat treatment was studied using X ray diffraction, differential thermal and thermo gravimetric analysis and transmission electron microscopy. It was found that the mechanochemical reaction process can be divided into two steps: the first step is the multi phases mechanochemical reaction of lanthanum carbonate with NaOH to form amorphous lanthanum basic carbonate and lanthanum hydroxide, and the second step is the crystallization of basic lanthanum carbonate with the formula of La 2(OH) 2(CO 3) 2·H 2O under a quasi hydrothermal synthesis condition caused by the mechanical ball milling. The synthesized La 2O 3 powder appears clearly separated spherical like monodisperse nano size particles in which particle size ranges from 30 to 50 nm.

Improvement of thermally grown oxide layer in thermal barrier coating systems with nano alumina as third layer

A thermally grown oxide （TGO） layer is formed at the interface of bond coat/top coat. The TGO growth during thermal exposure in air plays an important role in the spallation of the ceramic layer from the bond coat. High temperature oxidation resistance of four types of atmospheric plasma sprayed TBCs was investigated. These coatings were oxidized at 1000 °C for 24, 48 and 120 h in a normal electric furnace under air atmosphere. Microstructural characterization showed that the growth of the TGO layer in nano NiCrAlY/YSZ/nano Al2O3 coating is much lower than in other coatings. Moreover, EDS and XRD analyses revealed the formation of Ni（Cr,Al）2O4 mixed oxides （as spinel） and NiO onto the Al2O3 （TGO） layer. The formation of detrimental mixed oxides （spinels） on the Al2O3 （TGO） layer of nano NiCrAlY/YSZ/nano Al2O3 coating is much lower compared to that of other coatings after 120 h of high temperature oxidation at 1000 °C.

STRUCTURAL DETERMINATION OF TITANIUM-OXIDE NANOPARTICLES BY X-RAY ABSORPTION SPECTROSCOPY

As a potential application of titanium-oxide nanoparticles, it is extremely important to investigate a detailed picture of the surface and interior structural properties of nanocrystalline materials, such as rutile and anatase with diameters 7.0 and 4.5nm, respectively. X-ray absorption spectroscopy has been used to identify the local Ti environment and related electronic structure. We combine the experimental results at the Ti edge in both bulk and nano-crystals to determine the lattice distortion in terms of differently characteristic preedge features and the variation in the multiple-scattering region of X-ray absorption near-edge structure (XANES) spectra. The relationship between the transition peaks and the surface-to volume ratio is also discussed.

Zinc Oxide Nano Particles Integrated Kenaf/Unsaturated Polyester BioComposite

Increasing need for materials with special features have brought various new inventions,one of the most promising hope for new material with special features and functionalities is composites materials.Thus,this study report an integration of zinc nanoparticles into kenaf/polyester polymer composite to introduce new behavior to the composite.The composite behaviors were compared for mechanical,thermal,moisture absorption and biodegradability properties.Prepared Zinc Oxide nanoparticles entrenched in the kenaf/polyestaer composites net structure through chemical bonds between kenaf/ZnO/polyester resin,existence of ZnO significantly influence the mechanical and thermals properties of composites.Thermal analysis based on(TGA)response revealed the integration of ZnO nanoparticles improved the thermal stability when thermal decomposition temperature beyond 3650 C.The thermal cracking decreased with present of ZnO and increase with kenaf content(layers).The modulus,Tensile strength,break at elongation,flexural modulus,flexural strength and impact strength of the composites with higher content kenaf/ZnO nanoparticle are 560 MPa,58MPa,1.8%,1300 PMa,68 MPa and 31 MPa,respectively.Thus,addition of kenaf layers and ZnO results in larger mechanical properties enhancement,the results of the contact angle show improvement in wetting of the fibres with addition of ZnO nanoparticles.

Graphene oxide assisted facile hydrothermal synthesis of LiMn_(0.6)Fe_(0.4)PO_4 nanoparticles as cathode material for lithium ion battery

Assisted by graphene oxide（GO）,nano-sized LiMn0.6Fe0.4PO4 with excellent electrochemical performance was prepared by a facile hydrothermal method as cathode material for lithium ion battery.SEM and TEM images indicate that the particle size of LiMn0.6Fe0.4PO4（S2）was about 80 nm in diameter.The discharge capacity of LiMn0.6Fe0.4PO4 nanoparticles was 140.3 mAh-g^1 in the first cycle.It showed that graphene oxide was able to restrict the growth of LiMn0.6Fe0.4PO4 and it in situ reduction of GO could improve the electrical conductivity of LiMn0.6Fe0.4PO4 material.

Preparation of chain copper oxide nanoparticles by microwave

Cu（OH）2 nano-fibers were prepared by chemical precipitation with CuSO4·5H2O and NaOH as raw materials. The Cu（OH）2 nano-fibers have a diameter of 10-30 nm and a length of 1-6 μm. The reaction conditions were as follows： the concentration of CuSO4 solution was 0.1 mol·L^-1,NaOH solution 4 mol·L^-1,the dropping rate of the NaOH solution 50 mL·min^-1,the reaction temperature 20℃the pH value of the reaction terminal 13,and the stirring rate 1200 r·min^-1. The chain nano-CuO grains were obtained through the microwave radiation of the Cu（OH）2 nano-fibers.

A Novel Route to Synthesize Nano-crystalline Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O(3-δ) Perovskite Oxide at High Temperature

It is normally difficult to prepare nano-sized Ba0.5Sr0.5Co0.8Fe0.2O3-δ（BSCF） oxide at high temperature due to its high surface activity. The complexing process, which has successfully applied in the synthesis of nano Sm0.15Ce0.85I1.925 with crystallite size down to 5 nml, just resulted in a coarse BSCF with crystaUite size of 41.9 nm at 900℃. We applied a novel process by simply modifying the solid precursor from the complexing process with concentrated nitric acid treatment. The obtained BSCF powder had a crystaUite size of -25 nm even calcined at 1000℃. The small crystaUite size is extremely promising to enhance the electrochemical performance of cathode for solid oxide fuel cell dramatically.

Influence of MgO contents on silica supported nano-size gold catalyst for carbon monoxide total oxidation

A series of nano-size gold catalysts were prepared by deposition-precipitation method using silica material promoted with different amounts of MgO as the carrier. The influences of MgO addition on the structure and property of the nano-size gold catalysts were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM）, O2 temperature-programmed desorption （O2-TPD）, and inductively coupled with plasma atomic emission spectroscopy （ICP-AES） techniques. The total oxidation of CO was chosen as the probe reaction. The results suggest that for the gold catalysts supported on the silica material after MgO modification, the size of the gold particles is pronouncedly reduced, the oxygen mobility is enhanced, and the catalytic activity for low-temperature CO oxidation is greatly improved. The gold catalyst modified by 6 wt% MgO （Mg/SiO2 weight ratio） shows higher CO oxidation activity, over which the temperature of CO total oxidation is lower about 150 K than that over the silica directly supported gold catalyst.

Preparation of tin-oxide nanotubes as anode for Li-ion batteries

The influence of nanostructure on the electrochemical properties of Li-ion battery was investigated. Tin-oxide nanotubes were prepared by combining sol-gel method with polycarbonate template. Scanning electron microscopy and X-ray diffractometry were applied to characterize the obtained material. The electrochemical measurements were conducted on the nanostructured tin-oxides as electrode of Li-ion batteries. The XRD data indicate that the wall of tube is composed of cassiterite crystals of several nanometers. The electrochemical measurements show that the reaction under potential 0.1-0.2 V is possibly related to the tubular structure of the material. It is suggested that the trapping of Li by dangling bonds and defects sites also contributes to the larger irreversible capacity loss in the first discharge.

Removing Iron Ions Contaminants from Groundwater Using Modified Nano-Hydroxyapatite by Nano Manganese Oxide

In this article, we study modified nano-hydroxyapatite (HAp) by nano manganese oxide (Mn3O4) as adsorbent material to remove iron ions from groundwater. Different parameters were studied to option optimum conditions of removing such as contact time, pH, initial concentration, a dosage of adsorbent, agitation speed and temperature. Kinetics studies included first order (R2 = 0.915), pseudo-first order (R2 = 0.936), second order (R2 = 0.948), pseudo-second order (R2 = 0.995), Elovich equation model (R2 = 0.977), intraparticle diffusion (R2 = 0.946), Natarajan and Khalaf (R2 = 0.915) were carried out, the obtained results revealed that the pseudo-second order is the best to describe the adsorption process because the correlation coefficient is approaching one (R2 = 0.995). Adsorption isotherm was calculated by using Freundlich, Langmuir and Temkin constants, adsorption capacity from Langmuir model was 0.606 mg/g. Thermodynamic parameters (ΔG, ΔH = ?51 KJ/mol, and ΔS = ?142 (KJ/mol)) for the adsorption process were also calculated and discussed.

Modification Effect of Nano-Graphene Oxide on Properties and Structure of Polysulfone Ultrafiltration Membrane

In order to improve the purification properties of polysulfone (PSF) ultrafiltration membranes (UFM), nano-graphene oxide (nano-GO) was taken as modifier, and the physical blending process was adopted in our experiment. The microstructure, surface morphology and functional groups of modified UFM have been characterized respectively by scanning electron microscopy, atomic force microscopy and Fourier transform infrared spectroscopy, and the static contact angle between the membrane surface and the water droplet has also been detected to show the change of its hydrophilicity. Through experiments, it has been found that modified UFM has larger and more developed finger micro-pores, and there exist a large number of -OH groups on its surface, and also its hydrophilicity has been enhanced. The result of the experiments show that the modified UFM may keep rejection above 97% and its water flux can be reached at about 219.1 L/(m2·h) under pressure of 1 bar if 0.4 wt% of nano-GO was added. Additionally, the nano-GO can increase the flux recovery radio (FRR) of the membranes, and the maximum FRR was observed as 74.4% if 0.3 wt% of nano-GO was appended.

The Effect of Titanium Nano Oxide and Heat Treatment on Physical Properties of Hornbeam (<i>Carpinus betulus</i>) in Golestan Province

The use of wood has been considered for a long time and to this day, it has a special place in human life. Modification of wood and lignocellulosic materials is done by various methods, including modification of physical, mechanical, chemical and thermal, that as a new technology, it leads to the improvement of their undesirable features. Among these methods, heat correction is a useful method to improve dimensional stability and leads to increased resistance to water absorption and decay. The main purpose of this study is to investigate the titanium Nano oxide and heat treatment on the physical properties of hornbeam species. Samples were saturated with titanium Nano oxide solution at a concentration of 5000 ppm and pressurized 7 times in a pressure tank. The samples were divided into three groups: control, heat and Nano thermal treatment. Heat and saturated samples with titanium Nano oxide were heat treated at three temperature levels of 150℃, 175℃ and 200℃ for 4 and 6 hours. All three groups underwent physical tests. Heat and Nano thermal oxide treatments led to reduced water absorption and thickness swelling. Comparison between heat and Nano thermal treatment showed a further decrease in water absorption and thickness swelling in Nano thermal samples.