Influence of the Deposition Parameters on the Characteristics of Aerosol-Gel Deposited Thin Films

The aerosol-gel process is a thin film deposition process based on the sol-gel polymerisation of a liquid film deposited from an ultrasonically sprayed aerosol. This process offers an attractive alternative for the deposition of sol-gel thin films. The effects of the aerosol deposition route on the film characteristics have been investigated with regard to sol-gel chemistry. TEOS solutions have been studied by viscosimetry and FTIR spectroscopy using an ATR device. Silica xerogel coatings have been studied by transmission FTIR and optical microscopy. Film morphology and uniformity depend closely on the aerosol deposition conditions. The film growth is controlled by a droplet coalescence surface phenomenon.     

利用清洁工艺生产柠檬酸的研究

本文设计了一条生产柠檬酸的新工艺，可望有效的解决柠檬酸生产中的环境污染问题，并对生产过程中所产生的化合物的再次利用提出了新的方法，实验结果表明，利用该工艺生产柠檬酸，其收率可从传统的80％提高到89％，产生的污染物可下降80％以上。     

Preparation of A New Fiber by Sol-gel Technology in Solid-phase Microextraction （SPME）

The sol-gel technology is applied for the preparation of solid-phase microextraction (SPME) fiber. The fiber demonstrates high thermal stability, efficient extraction rate and the selectivity for non-polar or low-polar analytes. Efficient SPME-GC-FID analyses of benzenetoluene-ethylbenzene-xylenes (BTEXs) and low-polar halocarbon were achieved by the sol-gel coated DSDA-DDBT-TiO2 fiber. Some parameters of the SPME fiber for the determination of halocarbon in aqueous sample were investigated.     

Response surface methodology for the optimization of the ultrasonic-assisted rhamnolipid treatment of oily sludge

This study investigates the recovery of oily sludge using ultrasound-assisted rhamnolipids and uses oil recovery yield as an evaluation index. The Box–Behnken response surface method was employed to investigate the individual and interactive effects of four different operating factors: frequency, dosage, liquid–solid ratio, and stirring speed. The model optimization results showed that the order of degree of influence of these four factors is frequency > liquid–solid ratio > dosage > stirring speed. The mathematical model predicted the highest oil recovery yield as 92.27%, which was highly accurate (in the 95% confidence interval) as from the experimental results, the highest oil recovery yield was 89.95% under optimal reaction conditions (frequency = 25.58 kHz, dosage = 150.45 mg/L, liquid–solid ratio = 4.1:1 mL/g, and stirring speed = 407 rpm). Thus, the deviation from the prediction model was only 2.32%, indicating that this method provides a theoretical basis for the treatment of oily sludge and can be implemented for practical application in Huaidong in the Xinjiang Province.     

手性环丙烷二羧的合成

本文报道了超声技术应用于手性富马酸薄荷醇酯5CH2Br2, CH2CCl2CH3在零价钴与锌的作用下生成环丙烷二羧酸衍生物的反应结果。     

Partial molal volumes of ions in organic solvents. IV. Ethylene glycol

Apparent molal volumes have been measured for several electrolytes in ethylene glycol (EG) and the standard state partial molal volumes, V₂°, evaluated. Ultrasonic vibration potentials (uvp) have also been measured for most of the alkali metal halides in EG, and these employed to evaluate ionic partial molal volumes, V° (ion). The results show unambiguously that the uvp is essentially independent of solvent viscosity. The V₂° data have also been divided into ionic components by four other techniques including, the method of Mukerjee, the use of Ph₄AsBPh₄, the correspondence method and an extrapolation of V₂° for a series of tetraalkylammonium bromides as a funtion of cation molecular weight. With the exception of the latter technique, all methods used give 30±2 cm³-mol^–1 for V° (ion), although the uvp leads to the largest value for V° (ion). The divisions have been analyzed also with the aid of Hepler's equation, and the results suggest that the uvp method gives a more accurate division and that the EG dipole is more hindered than the dipole in ethanol.     

Volume and compressibility effects in the formation of metal-EDTA complexes

We used precise measurements of ultrasonic velocity and density to study the complexation of ethylendiaminetetraacetic acid (EDTA) with Mg²⁺, Ca²⁺, Sr²⁺, and Ba²⁺ at 25‡C and pH 12. From these measurements we obtained the changes in the molar concentration increment of the ultrasonic velocity δA, the apparent molar adiabatic compressibility δK_sΦ, and the apparent molar volume δV_Φ of complex formation. The hydration contributions δ(AV_h) to the volume effect of binding range from 39.6 to 46.6 cm³-mol^-1 while the hydration contribution to the adiabatic compressibility change in the binding, δ(δK_h), ranges from 103.9X 10^-4 to 131.1 X 10^-4 cm³-mol^-1-bar^-1. These data are interpreted in terms of dehydration of interacting molecules,i.e., transfer of water molecules from the hydration shells of cations and EDTA into the bulk water. The ratio δ(δV_h)/ δ(δV_h) is in the range 0.35 to 0.38 bar, indicating a dominant contribution from the dehydration of charged atomic groups in the volume and the compressibility effects of complex formation.     

从科技竞赛获奖作品分析化学研究性学习选题的科学性

统计分析了近11届（2007-2017年）全国青少年科技创新大赛中化学参赛项目以及荣获一等奖的项目在化学二级学科中的分布情况，结果显示：涉及交叉学科的材料化学专业获奖项目数量和质量占据的比例越来越大，有机化学和物理化学也是中学生探究课题的热门方向，获奖项目数量仅次于材料化学。基于分析数据，总结了各二级学科中学生选题较为集中的研究领域，并对教师指导学生开展研究性学习选题的思路和方法提出了建议。     

Rapid and Efficient Synthesis of Diaryl Carbazones using Microwave Technology

Diaryl carbazone is an important organic analytical reagent normally prepared by the oxidation of diaryl carbazine, but in literatures' methods, the yields were low and the procedures were trouble1,2. Recently, our laboratory reported some new methods for the preparation of diaryl carbazone from diaryl carbazine3,4. Generally, these methods have drawbacks such as tedious operation3, using large amounts of volatile and poisonous solvent which will pollute the environment inevitably3, long reaction time and complicated oxidation system4. In continuation of our studies on the synthesis of azo compounds, we decided to develop a new method to overcome the limitation.As we know, the application of microwave techniques for organic synthesis has attracted considerable interests in recent years5. Using microwave technology can enhance the selectivity and reactivity, increase the chemical yields and shorten the reaction time6. It has been widely used in a variety of organic reactions7,8. However, the synthesis of diaryl carbazones using microwave has not been reported so far.In this paper, a rapid and efficient synthesis of diaryl carbazones with NaBrO3/H2SO4 as oxidation system using microwave technology is reported for the first time. By this method, in short time (0.5 rmin), we have synthesized ten diaryl carbazones in good yields.In the oxidation study, we found that the acidic condition is necessary in these reactions.This method only needs cheap and easily available oxidants, simple instruments and easy work-up.In conclusion, It is a facile and rapid method for the preparation of diaryl carbazones from diaryl carbazines with NaBrO3/H2SO4.     

Production of fuel ethanol from rye and triticale by very-high-gravity (VHG) fermentation

Very-high-gravity (VHG) rye and triticale mashes, containing about 28.5 g dissolved solids/100 mL of mash supernatant, were prepared by adjusting water:grain ratios to 2:1. Because of high viscosity, which develops during mashing, it was necessary to pretreat ground rye-water slurries with viscosity-reducing enzymes. There were no viscosity problems during the preparation of triticale mashes. Fermentations were conducted at 20°C, with and without 16 mM urea as a nitrogenous supplement. All fermentations were completed within 120–144 h. Supplementation with urea shortened the times required for completion of fermentation by 33% for triticale and by 40% for rye. The fermentation efficiencies for both grains ranged between 90 and 93%. These values are comparable to those reported for wheat, implying competitiveness of rye and triticale as fermentation feedstocks to replace wheat. The final ethanol yields were 409 L for rye and 417–435 L for triticale/t (dry basis). For a given size of fermentation vessel, 33% more grain was used in the VHG fermentation process than in normal gravity fermentation. This resulted in a 35–56% increase in ethanol concentration in the beer, when fermentors were filled to a constant volume. The corresponding reduction in water use by about one-third would result in savings in energy consumption in mash heating, mash cooling, and ethanol distillation. Fermentation efficiencies and final ethanol yields obtained per unit weight of grain fermented were not significantly different from the normal gravity fermentations.