Mass Transfer Enhancement of Gas Absorption by Adding the Dispersed Organic Phases

Mass transfer enhancement of gas absorption by adding a dispersed organic phase has been studied in this work. Various dispersed organic phases （heptanol, octanol, isoamyl alcohol, heptane, octane, and isooctane） were tested respectively in the experiment. According to the theoretical model and experimental data, the overall volumetric mass transfer coefficient and enhancement factor were obtained under different dispersed organic phase volume fraction and stirring speed. The experimental results indicate that gas-liquid mass transfer is enhanced at different level by adding a dispersed organic phase. The best performance of enhancement were achieved with the dispersed organic phase volumetric fraction of 5% and under an intermediate stirring speed of 670 r·min^-1. Among the organic phases tested in the experiment, alcohols show better performance, which gave 20% higher enhance-ment of overall volumetric mass transfer coefficient than adding alkanes.

Two Organic Phase Suspension Polymerization for Novel Hypercrosslinked Resin Bead by Polycondensation of CMB

The suspension polymerization with two organic phases was adopted to prepare spherical hyper- crosslinked resin by self-polycondensation of 4,4＇-bis-（chloromethyl）- 1, 1＇-biphenyl （CMB）. The chemical structure,morphology and pore characteristics of the novel spherical resin were characterized with Fourier transform infrared spectroscopy （FTIR）, micrograph and Brunauer-Emmett-Teller （BET）. It is found that the suspension system and stirring speed impose a great influence upon the regularity and size distribution of hypercrosslinked beads. To prepare CMB resin beads with diameter of about 300 μm, the optimal condition is as follows： stirring speed 300 r·min^-1, and the volume ratio of the two organic phases （nitrobenzene/dimethyl silicon oil） 1 ： 5. After the self-polycondensation and sqccedent post-crosslinking of CMB monomer, the spherical adsorbent presents high spec^al surface area （1190 m^2· g^-1） and abundant pore^volume （0.714 cm^3· g^-1）, and could be potentially applied qn the adsorption of various organic molecules and synthesis of porous ion exchanger.

The establishment of Boron nitride@sodium alginate foam/polyethyleneglycol composite phase change materials with high thermal conductivity, shape stability, and reusability

Adopting organic phase change materials(PCMs) for the management of electronic devices is restricted by low thermal conductivity. In this paper, the composite PCMs are established by freeze-drying and vacuum impregnation. Herein, polyethylene glycol(PEG) is induced as heat storage materials, boron nitride(BN) is embedded as filler stacking in an orderly fashion on the foam walls to improve thermal conductivity and sodium alginate(SA) is formed as supporting material to keep the shape of the composite stable. X-ray diffractometry, scanning electron microscopy-energy dispersive spectrometer, thermal gravimetric analysis, thermal conductivity meter, differential scanning calorimeter, and Fourier transform infrared were used to characterize the samples and thermal cycles were employed to measure the shape stability. The results exhibit the BN@SA/PEG composite PCMs have good chemical compatibility, stable morphology, and thermal stability. Due to the high porosity of foam, PEG endows the composite PCMs with high latent heat(149.11 and 141.59 J·g^(-1)). Simultaneously, BN@SA/PEG shows an excellent heat performance with high thermal conductivity(0.99 W·m^(-1)·K^(-1)), reusability, and shape stability, contributing the composite PCMs to application in the energy storage field. This study provides a strategy to manufacture flexible, long-serving, and shape-stable PCMs via introducing BN@SA foam as a storage framework, and these PCMs have great potential in thermal management in the electronic field.

APPLICATION OF THE SULFONATE ESTER GROUP AS A LINKER FOR SOLID PHASE ORGANIC SYNTHESIS

A use of Sulfonate ester as a linker in synthesis of (-aminoalkanols was reported. Diols were tethered onto polystyryl sulfonyl chloride resin, yielding sulfonate resins (2). After cleaved by diethyl amine, diisopropylamine and propylamine respectively, three (-aminoalkanols were obtained.

Growth of a-Plane GaN Films on r-Plane Sapphire by Combining Metal Organic Vapor Phase Epitaxy with the Hydride Vapor Phase Epitaxy

Hydride vapor phase epitaxy （HVPE） is utilized to grow nonpolar a-plane GaN layers on r-plane sapphire templates prepared by metal organic vapor phase epitaxy （MOVPE）. The surface morphology and microstructures of the samples are characterized by atomic force microscopy. The full width at half maximum （FWHM） of the HVPE sample shows a W-shape and that of the MOVPE sample shows an M-shape plane with the degree of 0 in the high-resolution x-ray diffraction （HRXRD） results. The surface morphology attributes to this significant anisotropic. HRXRD reveals that there is a significant reduction in the FWHM, both on-axis and off-axis for HVPE GaN are compared with the MOVPE template. The decrease of the FWHM of E2 （high） Raman scat tering spectra further indicates the improvement of crystal quality after HVPE. By comparing the results of secondary- ion-mass spectroscope and photoluminescence spectrum of the samples grown by HVPE and MOVPE, we propose that C-involved defects are originally responsible for the yellow luminescence.

Amperometric Biosensors Sensitive to Organic Peroxides Based on Immobilization of Redox Organic Dyes and Horseradish Peroxidase in Polyester Ionomer Film

Simple and effective organic biosensors sensitive to organic peroxides such as 2 butanone per oxide and tertbutyl hydroperoxide are constructed by immobilizing a series of redox organic dyes and horseradish peroxidase in Eastman AQ polymer film. The organic dyes are methylene blue, methylene green, meldola blue, new methylene blue N and N methyl phenazine methosulphate. The biosensors display high sensitivity and fast response to tertbutyl hydroperoxide and 2 butanone peroxide because of high efficiency of electron transfer between immobilized horseradish peroxidase and the electrode via the redox organic dyes. The comparison of the biosensors employing different organic dyes is made in formal potential, linear range and response time.

Solid-Phase Synthesis of Acrylamide Using Polymer-Supported β-Selenopropionic Acid

A novel polystyrene-supported ?selenopropionic acid has been developed and applied to facile synthesis of acrylamides.

Traceless solid-phase synthesis of 3-substituted isoxazoles from polystyrene-supported vinyl selenide

A novel facile procedure for traceless solid-phase synthesis of 3-substituted isoxazoles in good yields and with excellent purities using polymer-supported vinyl selenide has been developed.

Solid-phase Synthesis of-Haloaldehydes from Polymer-supported 4-(Phenylseleno)morpholine

Polystyrene-supported 4-(phenylseleno)morpholine was synthesized and could be used as an efficient ?selenenylating agent for saturated aldehydes. ?Haloaldehydes were prepared by reaction of polystyrene-supported ?selenoaldehydes with bromine or sulfuryl chloride in good yield and high purity.

Solid-Phase Stereoselective Synthesis of (E)-1, 2-Disubstituted Ethenes from Polymer-Sopported a-Selenoaldehydes

Reaction of polymer-supported a-selenoaldehydes with Grignard reagents afforded polymer-bound B-hydroxyalkyl selenides, which treated with thionyl chloride and triethylamine leading to (E)-1, 2-disubstituted ethenes in good yield.

Solid-phase synthesis of (Z)-allyl iodides from 3-acetoxy-2-methylene-alkanoates with recyclable polymer-supported selenium bromide

Reaction of polystyrene-supported lithium selenide with 3-acetoxy-2-methylene-alkanoates afforded the corresponding allyl selenide resins and subsequent cleavage from the polymer by treating with methyl iodide to furnish （Z）-allyl iodides in good yields and high purities. The polymeric selenium reagent can be regenerated and reused. So it is a environmentally benign reagent.

Solid-phase Synthesis of Unsaturated β-Dicarbonyl Compounds from Polymer-supported 4-(Phenylseleno)morpholine

The solid-phase synthesis of unsaturated ?dicarbonyl compounds has been reported.

Comparison of conventional and inverted structures in fullerene-free organic solar cells

A n-type small molecule DC-IDT2E with 4,4,9,9-tetrakis（4-hexylphenyl）-indaceno[1,2-b：5,6-bt]dithiophene as a central building block, furan as rr-bridges, and 1,1 -dicyanomethylene-3-indanone as end acceptor groups, was synthesized and used as an electron acceptor in solution-processed organic solar cells （OSCs）. DC-IDT2F exhibited good thermal stability, broad and strong absorption in 500-850 rim, a narrow bandgap of 1.54 eV, LUMO of-3.88 eV, HOMO of-5.44 eV and an electron mobility of 6.5 × 10-4 cm2/（V.s）. DC-IDT2F-based OSCs with conventional and inverted structures exhibited power conversion efficiencies of 2.26 and 3.08% respec- tively. The effect of vertical phase separation and morphology of the active layer on the device performance in the two structures was studied.

Response time improvement of AlGaN photoconductive detectors by adjusting crystal-nuclei coalescence process in metal organic vapor phase epitaxy

AlGaN photoconductive ultraviolet detectors are fabricated to study their time response characteristics. Persistent photoconductivity, a deterring factor for the detector response time, is found to be strongly related to the grain boundary density in AlGaN epilayers. By improving the crystal-nuclei coalescence process in metal organic vapor phase epitaxy, the grain-boundary density can be reduced, resulting in an-order-of-magnitude decrease in response time.

Effects of InGaN barriers with low indium content on internal quantum efficiency of blue InGaN multiple quantum wells

Blue In0.2Ga0.8N multiple quantum wells （MQWs） with InxGa1-xN （x = 0.01 - 0.04） barriers are grown by metal organic vapour phase epitaxy. The internal quantum efficiencies （IQEs） of these MQWs are studied in a way of temperature-dependent photoluminescenee spectra. Furthermore, a 2-channel Arrhenius model is used to analyse the nonradiative recombination centres （NRCs）. It is found that by adopting the InGaN barrier beneath the lowest well, it is possible to reduce the strain hence the NRCs in InGaN MQWs. By optimizing the thickness and the indium content of the InGaN barriers, the IQEs of InGaN/InGaN MQWs can be increased by about 2.5 times compared with conventional InGaN/GaN MQWs. On the other hand, the incorporation of indium atoms into the intermediate barriers between adjacent wells does not improve IQE obviously. In addition, the indium content of the intermediate barriers should match with that of the lowest barrier to avoid relaxation.

Migration characterization of Ga and In adatoms on dielectric surface in selective MOVPE

Migration characterizations of Ga and In adatoms on the dielectric surface in selective metal organic vapor phase epitaxy （MOVPE） were investigated. In the typical MOVPE environment, the selectivity of growth is preserved for GaN, and the growth rate of GaN micro-pyramids is sensitive to the period of the patterned SiO2 mask. A surface migration induced model was adopted to figure out the effective migration length of Ga adatoms on the dielectric surface. Different from the growth of GaN, the selective area growth of InGaN on the patterned template would induce the deposition of InGaN polycrystalline particles on the patterned Si02 mask with a long period. It was demonstrated with a scanning electron microscope and energy dispersive spectroscopy that the In adatoms exhibit a shorter migration length on the dielectric surface.

A MOVPE method for improving InGaN growth quality by pre-introducing TMIn

We propose a metal organic vapor phase epitaxy(MOVPE) method of pre-introducing TMIn during the growth of uGa N to improve the subsequent growth of In Ga N and discuss the impact of this method in detail. Monitoring the MOVPE by the interference curve generated by the laser incident on the film surface, we found that this method avoided the problem of the excessive In Ga N growth rate. Further x-ray diffraction(XRD), photoluminescence(PL), and atomic force microscope(AFM) tests showed that the quality of In Ga N is improved. It is inferred that by introducing TMIn in advance, the indium atom can replace the gallium atom in the reactor walls, delivery pipes, and other corners. Hence the auto-incorporation of gallium can be reduced when In Ga N is grown, so as to improve the material quality.

A NEW POLYMER-BOUND 1,2-DIOL AS A PROTECTING AGENT FOR SYMMETRICAL DIALDEHYDE

A novel polymer-bound 1,2-diol, 3-polystyrylsulfonyl-1,2-propanediol (6) had been prepared by the reaction of sodium polystyrylsulfinate with allyl bromide, followed by oxidation and. hydrolysis or directly with 3-chloro-1,2-propanediol in the presence of a phase transfer catalyst, n-tetrabutylammonium iodide. The capacity of resin 6 for terephthaidehyde reached 1.43 mmol/g. The aldehydic groups attached to polymer 6 reacted with hydroxylamine hydrochloride or reduced by sodium borohydride giving p-formylbenzaldoxime (yield: 89%)and p-formyl-benzalcohol (yield: 734%), respectively. The high yields of these polymer-supported reactions showed that the polymer 6 possessed the effective isolation of its reactive sites.

Phase transitions in two organic salts based on 1,5-naphthalenedisulfonate

Two phase transition compounds,diethylammonium 1,5-naphthalenedisulfonate(1)and cyclohexylammonium 1,5-naphthalenedisulfonate(2),were screened from a series of organic salts based on 1,5-naphthalenedisulfonate.The phase transition behaviors were studied by differential scanning calorimetry,single-crystal X-ray analysis and dielectric measurements.Compounds 1 and 2 undergo phase transitions at about 202 and 148 K,respectively,accompanied by distinct dielectric changes.The origin of the phase transitions was ascribed to motional changes of the cations in the crystal lattices.

Sorption and phase distribution of ethanol and butanol blended gasoline vapours in the vadose zone after release

The sorption and phase distribution of 20% ethanol and butanol blended gasoline （E20 and B20） vapours have been examined in soils with varying soil organic matter （SOM） and water contents via laboratory microcosm experiments. The presence of 20% alcohol reduced the sorption of gasoline compounds by soil as well as the mass distribution of the compounds to soil solids. This effect was greater for ethanol than butanol. Compared with the sorption coefficient （Kd） of unblended gasoline compounds, the Kd of E20 gasoline compounds decreased by 54% for pentane, 54% for methylcyclopentane （MCP） and 63% for benzene, while the Kd of B20 gasoline compounds decreased by 39% for pentane, 38% for MCP and 49% for benzene, The retardation factor （R） of E20 gasoline compounds decreased by 53% for pentane, 53% for MCP and 48% for benzene, while the R of B20 gasoline compounds decreased by 39% for pentane, 37% for MCP and 38% for benzene. For all SOM and water contents tested, the Kd and R of all gasoline compounds were in the order of unblended gasoline 〉 B20 〉 E20, indicating that the use of high ethanol volume in gasoline to combat climate change could put the groundwater at greater risk of contamination,