Preparation of Mn3O4 Nanofibres via An Electrospinning Technique

Thin PVA/manganese acetate composite fibres were prepared by using sol-gel processing and electrospinning technique.After calcinations of the above precursor fibres,Mn3O4 nanofibres with a diameter of 50-200 nm could be successfully obtained.The fibres were characterized by SEM,FT-IR,XRD.The results showed that the crystalline phase and morphology of nanofibres were largely influenced by the calcination temperature.     

静电纺丝法制备NiO纳米纤维及其表征

纳米级NiO因具有优良的催化和热敏等性能而被广泛用于催化剂^[1]、电池电极^[2,3]、光电转化材料^[4～6]、电化学电容器^[7～8]等诸多方面.迄今,已成功地制备出N iO的纳米颗粒^[9]、纳米线^[10]及纳米薄膜^[11],但是对于具有准一维结构的NiO纳米纤维的制备及性能研究尚未见报道.     

Preparation of Co3O4 Nanofibers via an Electrospinning Technique

Thin PVA/cobalt acetate composite fibers were prepared by using sol-gel processing and electrospinning technique.After calcination of the above precursor fibers,Co3O4 nanofibers with a diameter of 50-150 nm could be successfully obtained.The fibers were characterized by SEM,FT-IR,WAXD,respectively.     

利用环糊精包结的醋酸镍制备NiO纳米粒子

NiO nanoparticles are prepared via thermal decomposition of nickel acetate coated by β-CD, and Characterized by using X-ray diffraction (XRD), transmission electron microscopy (TEM). Thermo-gravimetric (TG) analysis and electro spray mass spectrum (ESI-MS) are performed to investigate the thermal decomposition process and the possible formation mechanism of obtaining good morphology NiO nanoparticles by this method. Further, different CDs are used to prepare the precursors of inclusion complexes, and there are little affect of CD′s type on the NiO nanoparticles.     

NiO/ZnO Composite Derived Metal-Organic Framework as Advanced Electrode Materials for Zinc Hybrid Redox Flow Battery

NiO/ZnO composite derived metal-organic framework (MOF) is used as to modify carbon felt (CF) via a conventional solid-state reaction followed by ultrasonication. The prepared electrode material is used in zinc-hybrid redox flow batteries (RFBs) due to their high redox activity of Zn²⁺/Zn. The electrochemical performance of composite modified CF and pre-treated CF was studied by cyclic voltammetry (CV) in 0.5 M aqueous zinc chloride with 5 M potassium hydroxide solutions showed clear confirmation for enhanced electrocatalytic activity. The unique porous structure of NiO/ZnO-derived MOF with increased surface area improves the battery behavior significantlyThe peak current ratio for the as-prepared material is about 3 times higher than that of the pre-treated CF due to more active sites. Zinc-based RFB with modified CF electrode exhibited better electrochemical performance with voltage efficiency (VE, 88 %), which is higher than true redox flow batteries.     

One step simultaneous electrochemical synthesis of NiO/multilayer graphene nanocomposite as an electrode material for high performance supercapacitors

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Electrospinning preparation of NiO/ZnO composite nanofibers for photodegradation of binary mixture of rhodamine B and methylene blue in aqueous solution: Central composite optimization

One‐dimensional nanofiber of p‐type NiO/n‐type ZnO heterojunctions with various molar ratios of Ni to Zn at different calcination temperatures were successfully synthesized using the electrospinning method, and they were fully characterized. The photocatalysts thus obtained were applied in aqueous solutions for rhodamine B (RDB) and methylene blue (MB) degradation. The p–n heterojunctions built among the cubic structure NiO and hexagonal structure ZnO in the composite nanofiber are responsible for generation of electrons and holes and subsequently superoxide and hydroxyl radical production by carriers which lead to degradation of the dyes in solution. The composite nanofibers (ZnNi1) calcined at 550 °C for 3 h showed the highest photocatalytic activity for degradation of the dyes in aqueous solution. The optimum values were found to be 180 min, 7.0, 1 g l^?1 and 3.0 and 3.0 mg l^?1 for irradiation time, pH, photocatalyst dosage and initial concentration of RDB and MB, respectively. For these optimum conditions, the photocatalytic degradation of RDB and MB was found to be 99.37 and 98.44%, respectively. The maximum photodegradation of RDB and MB using ZnNi1 was 59.41 and 65.43%, respectively. First‐order kinetics based on the Langmuir–Hinshelwood model successfully fitted the experimental data.     

A generalized technique for the encapsulation of nano‐sized NiO particles by styrene‐2‐hydroxyethyl methacrylate copolymer

Encapsulation of nickel oxide (NiO) particles is of great interest to the researchers as such modification produces remarkable improvement in properties and versatility in application potential. In this investigation, nanosized NiO particles were first prepared by calcination of nickel hydroxide precursor obtained using a simple liquid‐phase process. The produced NiO particles were stabilized with oleic acid and then treated with tetraethylorthosilicate to produce NiO/SiO₂ composite seed particles. Finally tri‐layered inorganic/organic composite particles were prepared by seeded copolymerization of styrene and 2‐hydroxyethyl methacrylate (HEMA) in the presence of NiO/SiO₂ composite seed particles. The produced composite particles named as NiO/SiO₂/P(S‐HEMA) were colloidally stable, and the obtained particles were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy and thermogravimetric analyses. Copyright © 2015 John Wiley & Sons, Ltd.     

A Novel Method to Synthesize Polyorganozircosilazane

A new kind of polyorganozircosilazane as Si/Zr/C/N-based ceramic precursor was synthesized from the condensation reaction of hexamethyleyclotrisilazane lithium salts(D3^NLi）and zirconium tetrachloride(ZrCl4).In the presence of N,N,N’,N’-tetramethyl ethylene diamine(TMEDA),polyorganozircosilazane was obtained in high yield.     

一种制备活性氧化铝的新方法

将结晶氯化铝与柠檬酸及淀粉等造孔剂混合,经直接干燥和焙烧制得了一种无定形活性氧化铝,并通过X射线粉末衍射、N2物理吸附及氨程序升温脱附等手段对活性氧化铝样品进行了表征,探讨了各组分对活性氧化铝样品性质所起的作用.与常规的活性氧化铝制备方法相比,这种制法省去了中和、老化、过滤和洗涤等步骤,缩短制备周期且过程容易控制.活性氧化铝具有适宜且可调节的比表面积和孔径分布,作为载体负载镍金属组分制成负载型催化剂后,对乙苯加氢饱和与加氢裂化表现出较高的催化活性.     

A novel composite derived from a metal organic framework immobilized within electrospun nanofibrous polymers: An efficient methane adsorbent

In this study, tantalum(V) metal organic framework (Ta-MOF) nanostructure was incorporated within polyvinyl alcohol (PVA) nanofibers to prepare an electrospun porous composite as a novel CH₄ adsorbent. The crystallinity, thermodynamic behavior, and textural properties of the products were investigated using instrumental analyses techniques. The results confirmed that the developed PVA/Ta-MOF electrospun nanofibrous composite exhibits higher thermal stability, considerable porosity, and larger surface area compared to the parent Ta-MOF. A 2^k factorial design was used for systematic study of the adsorption process. The results of response surface methodology (RSM) optimization indicated that the highest methane adsorption can be achieved at 24.40 °C and 3.70 bar in 23.60 min. These nano pore sorbents showed a significant potential for CH₄ adsorption due to the presence of Ta-MOF at the surface of nanofibrous composite compared to many other conventional sorbents that have been already used. This study introduces a novel biocompatible/biodegradable nanofibrous composite material with high methane adsorption performance and potentials for other applications.     

NiO nanoparticles prepared via thermal decomposition of the bis(dimethylglyoximato)nickel(II) complex: A novel reusable heterogeneous catalyst for fast and efficient microwave-assisted reduction of nitroarenes with ethanol

NiO nanoparticles with an average size of 12 nm and a high specific surface area of 88.5 m²/g were easily prepared via the thermal decomposition of the complex Ni(dmgH)₂ and were characterized by TGA, XRD, FT-IR, TEM and BET surface area measurement. This nanosized transition metal oxide was used as a new heterogeneous catalyst for the reduction of nitroarenes under microwave irradiation. The efficient and selective reduction of aromatic nitro compounds into their corresponding amines was observed by using ethanol as a hydrogen donor (reducing agent) and KOH as a promoter under microwave irradiation. This highly regio- and chemoselective method is fast, simple, inexpensive, high yielding, clean and compatible with several sensitive functionalities, such as halogens, -OH, -OCH₃, -CHO, -COCH₃, -COOH, -COOEt, -CONH₂, -CN, -CHCH₂ and -NHCOCH₃. This method is suitable for the large scale preparation of different substituted anilines as well as other arylamines. In addition, the catalytic activity of nanosized NiO is higher than that of the bulk sample.     

A Novel Electrocatalysis Method for Organic Pollutants Degradation

As typical contaminants, phenolic pollutants are wide spread and are toxic to aquatic life. Thus the demand for new technology to remove or detoxify such organics should be widely recognized. Recently, electrochemical method has attracted a great deal of attention for treating such kinds of wastewater, mainly because of its amenability to automation, high efficiency and environmental compatibility1. Various electrochemical processes have been developed and anodic oxidation might be the most w…     

A Novel High Active TiO2/AC Composite Photocatalyst Prepared by Acid Catalyzed Hydrothermal Method

A high active novel TiO2/AC composite photocatalyst was prepared and used for phenol degradation. It was much more active than P-25 and exhibiting good decantability, less deactivation after several runs and less sensitive to pH change. Diffuse reflectance spectra (DRS) revealed that the electronic change in TiO2 did not occur by the addition of AC. Results of SEM and XRD suggested that better TiO2 distribution can be achieved when optimal AC content was adopted. The performance of the prepared TiO2/5AC catalyst revealed great practical potential in wastewater treatment field.     

A Novel Method for Fabrication of a Glass-Electrode-Based Lipase Sensor

Lipase is one of the hydrolases. It catalyzes the hydrolysis of triglycerides, liberating fat acids. Based on its catalysis and the response of a glass electrode to the acids, a glass-electrode-based lipase sensor can be fabricated1, which has great potential in clinical medicine for the detection of blood fat in human serum samples.The immobilization of lipase on the bulb of a glass electrode is the key to the development of the sensor. In addition to its response time, which has a lot to do …     

A Novel Method for Modification of SMPU by Micro-phase Separation Promoters

Shape memory polyurethane(SMPU)is a typical temperature-sensitive functional polymer having an excellent shape memory behavior1,which has been extensively studied since19882,10.B.K.Kim et al.3reported the effect of hard segment contents(HSC)and soft segment length(SSL)of SMPU on its modulus,hardness and recovery strain.They attributed these effects to its micro-phase separation of its soft segment and hard segment as well as its soft segment crystallization.F.K.Li et al.4found that high…     

A Novel Method for the Synthesis of Carboxylic Esters Catalyzed by Expandable Graphite

Esterification reaction of carboxylic acid and alcohol has been carried out in excellent yield with expandable graphite as a catalyst.     

A Facile Method for Preparation of Superhydrophobic Surfaces with Poly(furfuryl Alcohol)/PTFE Composites

A stable superhydrophobic surface have been fabricated with poly(furfuryl alcohol) (PFA)/polytetrafluoroethylene (PTFE) composite coatings on steel substrates by using a facile method. The observation of field emission scanning electron microscopy revealed that the hierarchical microstructures formed on the surfaces are controlled by varying the curing temperature. This method can be easily operated on substrates of steel, therefore is readily developed to other engineering metal substrates such as aluminum, copper, etc.     

A New Method for the Synthesis of C/D Ring Synthon of Vitamin D

Inrecentyears,vitaminDresearchareahasbeenstimulatedbythediscoveriesthatIQ,25-dihydroxyvitaminD,,theactivemetaboliteofvitaminD,,inadditiontotheclassicalrolesofregulatingcalciumandphosphorusmetabolisms',hasamuchbroaderspectrumofactivitiesthanoriginallythought,suchaspromotingcelldifferelltiationandinhibitingcellproliferation"'.Thebiologicalsignificanceandmedicalneedshaveledeffortstowardthesearchforanaloguesofpotentcelldifferelltiationandantiproliferationactivitywithouttoxichypercalcemiaassociate…