ELECTROCHEMICAL COPOLYMERIZATION OF 3-(4-FLUOROPHENYL)THIOPHENE AND 3-METHYLTHIOPHENE IN BORON TRIFLUORIDE DIETHYL ETHERATE

The copolymer poly（3-（4-fluorophenyl）thiophene-co-3-methylthiophene） was successfully prepared from mixtures of 3-（4-fluorophenyl）thiophene （FPT） and 3-methylthiophene （MET） via electrochemical oxidation in boron trifluoride diethyl etherate （BFEE） and its mixed electrolytes with acetonitrile （ACN）. The influence of monomer concentration ratios on the copolymerization was investigated by using linear sweep voltammetry and cyclic voltammetry. The structure and morphology of these copolymer films were elucidated by UV-Vis, infrared spectroscopy, elemental analysis, thermal analysis and scanning electron microscopy （SEM）, respectively. The results showed that the molar ratio of FPT and MeT units, when copolymer was electrodeposited from feed ratio of FPT：MeT = 1：2, was about 1.08：1. In addition, the introduction of ACN into BFEE has little effect on the properties of as-formed copolymers.

ELECTROCHEMICAL COPOLYMERIZATION OF DIBENZOFURAN AND 3-METHYLTHIOPHENE IN BORON TRIFLUORIDE DIETHYL ETHERATE

The copolymerization of dibenzofuran(DBF)and 3-methylthiophene(MET)was successfully achieved electrochemically by direct anodic oxidation of the monomer mixtures in boron trifluoride diethyl etherate.The effects of applied polymerization potential and the monomer concentration ratios on the copolymerization were investigated by linear sweep voltammetry and cyclic voltammetry(CV).The structure of copolymer films were investigated by UV-Vis,infrared spectroscopy,thermal analysis.As-formed novel copolymers own...

ELECTROCHEMICAL POLYMERIZATION OF 5-CYANOINDOLE IN MIXED ELECTROLYTES OF BORON TRIFLUORIDE DIETHYL ETHERATE AND DIETHYL ETHER

High quality poly（5-cyanoindole） （P5CI） films were electrosynthesized by direct anodic oxidation of 5-cyanoindole on stainless steel sheet in the mixed electrolytes of boron trifluoride diethyl etherate （BFEE） and diethyl ether （EE） （by volume 1：1） ＋ 0,05 mol L^-1 Bu4NBF4. The film formed can be peeled off the electrode into freestanding films, The addition of EE into BFEE can improve the solubility of monomer. P5CI films obtained from this medium showed excellent electrochemical behavior with conductivity of 10^-2 S cm^-1, Structural studies showed that the polymerization of 5-cyanoindole occurred at the 2,3 position. As-formed P5CI films were thoroughly soluble in strong polar organic solvent dimethyl sulfoxide （DMSO） while partly soluble in tetrahydrofuran （THF） or acetone. Fluorescence spectral studies indicated that P5CI was a good blue-ight emitter.

Hydrolysis of Carbonyl Sulfide in Binary Mixture of Diethylene Glycol Diethyl Ether and Water

The solubility and hydrolysis of carbonyl sulfide in binary mixture of diethylene glycol diethyl ether and water are studied as a function of composition. The use of an aqueous solution of diethylene glycol diethyl ether enhances the solubility and hydrolysis rate of carbonyl sulfide compared with that in pure water. The composition of the mixture with maximum hydrolysis rate varies with temperature. The thermophysical properties including density, viscosity, and surface tension as a function of composition at 20℃ under atmospheric pressure as well as liquid-liquid equilibrium (LLE) data over the temperature range from 28℃ to 90℃ are also measured for the binary mixture.

Performance and combustion study of a low heat rejection engine running with biogas–diethyl ether–diesel

The present research focuses on addressing the faster depletion of fossil fuels and environmental pollution in addition to the energy crisis that hinders the progress of a nation.In the current research,waste banana leaves were considered as substrates for biogas production.Biogas is taken as the primary fuel in dual fuel(DF)operations to maximize possible diesel savings.The performance and combustion assessment were executed in a low heat rejection(LHR)engine using 5%diethyl ether by volume blended with diesel(5DEE)as pilot fuel.The combustion attributes of the engine reveal that the apex of net heat release rate(NHRR)curve retarded a bit as compared to apex of base result.The peak cylinder pressure was noted to be 6.19 MPa in the LHR engine running with 5DEE+biogas at 11.7°crank angle(CA)after top dead center(aTDC)compared to 5.23 MPa for the diesel alone operation at the same position.The apex point for NHRR was observed to be 54.51 J(°)^(−1)for 5DEE+biogas in LHR engine positioned at 3.2°aTDC.The brake thermal efficiency at full engine load operation decreased by 12.7%and 5.2%for biogas substitutions of 0.8 kg h^(−1)with diesel and 5DEE,respectively,compared to the base result.The smoke opacity and nitric oxide emissions were reduced during the DF run accompanied by diethyl ether as a fuel additive.

Volatile components of Rhizoma Alpiniae Officinarum using three different extraction methods combined with gas chromatography-mass spectrometry

Volatile components from Rhizoma Alpiniae Officinarum were respectively extracted by three methods including hydrodistillation, headspace solid-phase microextraction （HS-SPME） and diethyl ether extraction. A total of 40 （hydrodistillation）, 32 （HS-SPME） and 37 （diethyl ether extraction） compounds were respectively identified by gas chromatography-mass spectrometry （GC/MS） and 22 compounds were overlapped, including β-farnesene, 7-muurolene, 2,6-dimethyl-6- （4-methyl-3-pentenyl）bicyclo[3.1.1]hept-2-ene, eucalyptol and cadina-1（10）, 4-diene and so forth, varying in relative contents. HS-SPME is fast, sample saving and solvent-free and it also can achieve similar profiles as those from hydrodistillation and solvent extraction. Therefore, it can be the priority for extracting volatile components from medicinal plants.

Chemical Interpretation on the Multi-Stage Oxidation of Diethyl Ether

Multi-stage ignition and/or double NTC(negative temperature coefficient)behavior resulted from the low-temperature oxidation of ether compounds are still not clearly explained.We have investigated the oxidation mechanism of a stoichiometric DEE(diethyl ether)/air mixture by using a micro flow reactor with a controlled temperature profile to see the detail of low-temperature weak flame structure.The simulation was also performed to understand the chemical kinetics mechanism of observed weak flame structure.Chemiluminescence measurement showed separated weak flame in the temperature range of 600 K-800 K.The simulation also qualitatively reproduced this separated weak flame,and showed four peak of heat release.From the reaction flow analysis,it was found that(1)O-O bond scission reaction of keto-hydroperoxide produced by DEE,(2)O-O bond scission reaction of CH3O2H,CH3CO3H,and C2H5O2H,(3)O-O bond scission reaction of H2O2,and(4)H+O2=O+OH are key chain branching reactions to explain the multi-stage oxidation.

Insecticidal Activity of Crude Extracts of Hyptis suaveolens(Bush Mint)on Anopheles Mosquitoes Collected from Lafia,Nasarawa State,Nigeria

Anopheles gambiae is a vector that is responsible for the transmission of malaria parasites which causes high morbidity and mortality in Nigeria and the world at large.Human-vector contact can be reduced by the use of conventional repellents being sold in the market,though some of these repellent are not environmentally friendly and An.gambiae have developed resistance to some of these repellents.To this end,the phytochemical constituents and insecticidal activity of crude extracts of Hyptis suaveolens(bush mint)was determined on adult An.gambiae mosquitoes collected from Lafia,Nasarawa State,Nigeria to evaluate its effect in controlling them.Here,70%ethanolic and diethyl ether fat crude extracts were made from H.suaveolens dried leaves and used to carry out the experiment.The phytochemical screening of the ethanol extract revealed the presence of alkaloids,flavonoid,saponins,tannins,steroids and reducing sugar.Glycoside was not detected in the ethanol extract.Only steroids was detected in diethyl ether extract the rest of the phytochemical tested were absent.An.gambiae larvae were collected from the field and were raised to F1 progeny adults that were used for the study.WHO protocol for carrying out human bait repellency cage test was used.Human hand treated with the extracts was exposed to a cage containing 30 female mosquitoes for each of the extracts respectively.The ethanolic crude extract treatment proved to be more effective in repelling mosquitoes with 0%(0/30)mosquito landing than diethyl ether extract which had 40%(12/30)mosquitoes landing and the control hand(untreated left hand)had the highest landing rate 63.3%(19/30)which showed very high significant difference(χ^(2)=27.2619,df=2,P<0.00001)in relation to the treatments.After 24 hours holding period,the mortality rate of exposed mosquitoes was observed to be highest in the ethanolic treatment 73.3%(22/30).In conclusion,H.suaveolens extracts have repellency potential in controlling adult An.gambiae.

Detection of Diethyl Ether by a Europium MOF through Fluorescence Enhancement

A new water-stable europium MOF,(Me_(2)NH_(2))[Eu(abtc)(phen)]·2H_(2)O (1),has been synthesized from Eu(NO_(3))_(3)·6H_(2)O with 1,10-phenanthroline (phen) and 3,3′,5,5′-azobenzenetetracarboxylic acid (H_4abtc) ligands under solvothermal conditions and structurally characterized by single-crystal X-ray diffraction analysis,IR,TGA and PXRD.It crystallizes in monoclinic system,C2/c space group,with a=16.278(3),b=14.261(3),c=27.936(5)?,b=103.464(3)°,V=6307(2)A^(3),Z=8,C_(30)H_(26)Eu N_5O_(10),M_(r)=768.5,D_(c)=1.543 g/cm^(3),F(000)=2912,m(Mo Ka)=2.044 mm^(-1),R=0.0315 and w R=0.0663.In the structure of 1,the Eu O_7N_(2) polyhedra are assembled into a 2D layer with rhombic windows and these layers are further condensed to form a 3D framework.It can be used as selective and sensitive fluorescence sensors capable of detecting diethyl ether vapor.

Capacitive properties of low potential electro-polymerized polyfluorene and activated carbon composite electrode

Polyfluorene (PF) film has been successfully electropolymerized at lower potential (0.91 V vs.Ag/AgCl) in the mixed electrolyte of boron trifluoride diethyl etherate and trifluoroacetic acid.The PF film is characterized to have about 10 repeat units and no presence of ketonic defect site.UV-vis and photoluminescent spectral studies indicate that the PF film is blue light emitting.From cyclic voltammetry and galvanostatic charge-discharge tests in 1 M lithium perchlorate/acetonitrile electrolyte,the polyfluorene/activated carbon electrode shows a specific capacitance of 227.1 F g-1 (per active layer mass) and reversible redox reaction at the potential of 1.4 V in a three electrode configuration.An asymmetric electrochemical capacitor based on this composite electrode and activated carbon electrode exhibits a specific energy of 14.7 Wh kg-1 (per active layer mass).These results indicate that electrochemically prepared polyfluorene could be used as energy storage component for electrochemical application.

LOW-POTENTIAL ELECTROSYNTHESIS OF CONDUCTING AND ELECTROACTIVE OLIGOCATECHOLBORANE WITH BLUE LIGHT-EMITTING PROPERTIES

Novel conducting oligocatecholborane （OCOB） with electrical conductivity of 3.73 × 10^-2 S cm-1 was successfully synthesized by low-potential electropolymerization of catecholborane （COB） in boron trifluoride diethyl etherate at 0.70 V versus Ag/AgC1. FT-IR and ^1H-NMR spectra, together with the computational results, proved that COB was polymerized through the coupling at C（4） and C（5} positions and the reactive B- H bond was stable during the electrochemical polymerization. The resulting product was mainly composed of oligomers with short chain lengths by GPC and mass spectral results. The as-formed OCOB film showed good electrochemistry in monomer-free electrolytes with the electrochromic property from opaque blue to sap green. Fluorescence studies indicated that soluble OCOB can emit bright blue light under excitation of 365 nm UV light with the maximum emission at 396 nm and a fluorescence quantum yield of 0.21. The deposited OCOB also exhibited favorable thermal stability and smooth and compact morphology even at high magnifications.

AN ELECTROCHEMICALLY PREPARED SKY-BLUE LIGHT EMITTING ETHER FUNCTIONALIZED POLYFLUORENE AS CHEMOSENSOR FOR METAL IONS

Synthesis and electrochemical polymerization of 9,9-bis（2-（2-（2-methoxy ethoxy）ethoxy）ethyl）-fluorene （EO-F） into poly[9,9-bis（2-（2-（2-methoxy ethoxy）ethoxy）ethyl）-fluorene] （EO-PF） films are reported. The boron trifluoride diethyl etherate electrolyte enables facile preparation of EO-PF films at lower potential compared to LiCIOa/MeCN and the electrochemical polymerizations are discussed. The EO-PF shows good electrochemical behavior and can be dissolved in solvents such as DMSO and THF. The solubility of EO-PF in THF is 2 mg.mL-1 and the number average molecular weight is 35300 with a polydispersity index of 1.65. The side chains on C9 position of the monomer maintain unchanged aRer electrooxidation into corresponding polymer. The EO-PF dissolved in THF under 365 nm ultraviolet light is sky blue light emitting with the Commission Internationale de L＇Eclairage-CIE coordinates of （0.19, 0.15）. The electropolymerized EO-PF is used for the first time in chemosensing metal ions, demonstrating fluorescence quenching for Mn2＋ and Fe3＋ while fluorescence enhancement for Cr6＋ ions.