钴铜双金属微波催化剂的制备及性能研究

以硝酸铜和硝酸钴为原料、尿素为沉淀剂,微波功率320 W,反应时间30 min,制备了钴铜双金属氢氧化物(CuCo-LDH)。通过表征结果得知,与其他制备方法相比,微波法制备的催化剂具有良好的结晶度、立体结构,并能提供更多的活性位点,具有较高的催化活性。在微波辅助下,CuCo-LDH中的Cu^(2+)、Cu^(+)、Co^(3+)、Co^(2+)与H_(2)O_(2)形成类芬顿反应耦合体系,甲基橙(MO)脱色率可达99.78%。本研究为双金属复合催化剂在水处理中的应用提供了有益参考。

磷酸锆镍的微波制备及其可见光光催化性能

以氧氯化锆、氯化镍和磷酸二氢钠为原料,在较低温度和常压条件下采用微波辅助法制备具有特殊形貌的磷酸锆镍NiZr(PO_4)_2·4H_2O。研究了3种不同种类的表面活性剂对磷酸锆镍的物相、尺寸及形貌的影响。结果表明,表面活性剂的引入可以降低磷酸锆镍颗粒的平均粒径。与十二烷基硫酸钠(SDS)相比,聚乙烯吡咯烷酮K30(PVP-K30)和十六烷基三甲基溴化铵(CTAB)对颗粒生长的抑制程度更大,从而产物的平均粒径更小。使用亚甲基蓝(MB)溶液模拟印染废水,对磷酸锆镍的光催化降解性能进行了探讨。结果表明,可见光下以PVP-K30为模板制备的磷酸锆镍对MB的表观脱色率为49.0%,优于CTAB和SDS条件下制备的磷酸锆镍。本文为新型磷酸锆类复盐的制备与应用研究提供了新的思路和方法。

基于微波前处理技术快速测定生物样品中放射性核素的γ能谱方法

建立以大容量微波干燥碳化灰化一体装置为载体制备生物灰样、采用高纯锗γ能谱法直接测量生物灰样放射性核素的生物样品分析测定方法,实现核电厂周边环境生物样品中γ放射性核素活度浓度的快速测定。与传统灰样制备法对比研究结果表明:该微波灰样制备法可使生物样品制样效率提高约2~5倍,平行样相对偏差小于14.8%,加标回收率为87.0%~116%。采用配对t检验法验证,二者之间无显著性差异。该方法具有准确度高、分析效率高、操作简单、安全环保等优点,是快速测定生物样品中γ放射性核素活度浓度的理想方法。

Preparation of κ-carra-Oligosaccharides with Microwave Assisted Acid Hydrolysis Method

A rapid method of microwave assisted acid hydrolysis was established to prepare κ-carra-oligosaccharides. The optimal hydrolysis condition was determined by an orthogonal test. The degree of polymerization （DP） of oligosaccharides was detected by high performance thin layer chromatography （HPTLC） and polyacrylamide gel electrophoresis （PAGE）. Considering the results of HPTLC and PAGE, the optimum condition of microwave assisted acid hydrolysis was determined. The concentration of κ-carrageenan was 5 mgmL-1; the reaction solution was adjusted to pH 3 with diluted hydrochloric acid; the solution was hydrolyzed under microwave irradiation at 100 ℃ for 15 min. Oligosaccharides were separated by a Superdex 30 column （2.6 cm × 90 em） using AKTA Purifier UPC100 and detected with an online refractive index detector. Each fraction was characterized by electrospray ioni- zation mass spectrometry （ESI-MS）. The data showed that odd-numbered κ-carra-oligosaccharides with DP ranging from 3 to 21 could be obtained with this method, and the structures of the oligosaccharides were consistent with those obtained by traditional mild acid hydrolysis. The new method was more convenient, efficient and environment-friendly than traditional mild acid hydrolysis. Our results provided a useful reference for the preparation of oligosaceharides from other polysaccharides.

Preparation of BaAl_2O_4 by microwave sintering

The desulfurater(BaAl2O4) was successfully synthesized with BaCO3 and Al(OH)3 powders as raw materials by microwave sintering method.The mass loss of raw materials and the characterization of the outcome were investigated by means of TG-DSC,XRD and optical microscopy.The reaction mechanism was discussed.The experimental results show that synthesized BaAl2O4 by microwave sintering method is feasible.Compared with conventional sintering method,microwave sintering is a better way to synthesize BaAl2O4 with advantages of low temperature sintering,short time sintering and high synthesis rate.

Study on Microwave Preparation of Conjugated Linoleic Acid from Corn Germ Oil

[Objective] The optimal craft of preparing conjugated linoleic acid from corn germ oil by dint of microwave method was studied. [Meth- od] Microwave power, microwave mode of action, the amount of catalyst and solvent were selected for single-factor-experiment. Then, based on the single-factor-experiment, the catalyst and solvent amount, and microwave function time were chosen for orthogonal experiment so as to deter- mine the optimal craft of preparing CLA from corn germ oil. UV absorption spectra and infrared absorption spectrum were used to analyse the struc- tural features of natural corn germ oil and CLA. [Resalt] The optimal preparation condition was as follow： the catalyst was 0.6 times heavier than oil, solvent was 3 times heavier than oil weight, microwave worked for ten minutes. Under the optimal condition, CLA was 56.3% and conversion rate was 99.47 %. The results indicated that non-conjugated double bonds of linoleic acid can be isomerized and changed into conjugated double bonds under the conditions of microwave irradiation,[ Conduslon] The study provided a new way for the preparation of CLA.

A Novel Method for Producing Hydrogen from a Hydrocarbon Liquid Using Microwave In-liquid Plasma

The in-liquid plasma method is a technology in which plasma of several thousand degrees Kelvin is generated within bubbles in a liquid. The purpose of this study is to enhance the hydrogen production rate from waste oils by using in-liquid plasma. Two types of microwave in-liquid plasma apparatus are adopted for hydrogen production. One is a conventional MW （microwave） oven, the other is a microwave generator with a waveguide to apply the in-liquid plasma steam reforming method in n-dodecane. The produced gas is 58%-90% hydrogen in these methods. The hydrogen production rate is improved by stabilization of the bubble growth. The gas production rate by plasma feeding steam in n-dodecane is 1.4 times higher than that without feeding steam.

A rapid protein sample preparation method based on organic-aqueous microwave irradiation technique

Fast and efficient sample preparation methods are a prerequisite for protein identification in bottom-up proteomics. Here, an innovative microwave irradiation sample preparation method was developed based on an optimized organic-aqueous solvent system for protein identification. Specifically, protein solutions containing high-concentration acetonitrile were subjected to 5 min microwave irradiation. After cooling down, trypsin was added and the digestion was performed with 30 s microwave irradiation, and the resulting peptides were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS). A shortened processing time of only 5.5 min is needed with this method(more than 12 h is necessary in the traditional overnight protein sample preparation). Moreover, due to the absence of urea and other chaotropic reagents, the digests can be readily identified by MALDI-TOF MS. When an assessment of this method was performed by digesting a model protein BSA, 69% ± 3% sequence coverage corresponding to 47 ± 3 peptides was obtained, which shows better protein identification than that from the standard overnight protein sample preparation method(51% ± 2% sequence coverage and 23 ± 1 peptides). Another model protein α-casein was used for the analysis of protein phosphorylation with the newly developed method that yielded 4 phosphopeptides with 8 phosphorylation sites, whereas 3 phosphopeptides with 2 phosphorylation sites were obtained from the traditional overnight approach. Moreover, the organic-aqueous microwave irradiation method provides effective digestion for proteins down to fmol.