固载化离子液体的制备及其在有机反应中的应用进展

固载化离子液体是通过物理吸附或化学键合的方法将离子液体与载体结合形成的一种固体催化剂,既保留了离子液体优良的催化活性,又结合了载体高比表面积的特性,从而有效降低了离子液体的用量,还提高了催化剂的重复使用性能,因而被广泛应用于有机反应中。综述了近几年来国内外有关载体材料分类、固载化离子液体的制备及其在偶联、环化、缩合、氧化等反应中应用的研究进展。

不同温度制备蛹虫草液体菌种对菌种性能的影响

以经活化处理的优质蛹虫草试管种为母种,分别以16℃、20℃、24℃、28℃四种不同温度制备蛹虫草液体菌种;通过比较各温度实验组制备液体菌种的形态、生物量大小及其主要培养性状,以实际栽培试验性能特征及产量结果为主要指标,探索蛹虫草优质液体菌种制备的适宜温度。结果表明,以20℃、24℃制备液体菌种性能依次最佳,16℃制备菌种次之,28℃制备菌种性能下降明显、出草产量明显较低。说明蛹虫草液体菌制备适宜温度以20-24℃为宜,过高制备温度不利于保持菌种优良性能。

液体菌种制备中的问题发生及解决

液体菌种技术对企业生产发展起到了重要的推动作用,但仍有许多单位在实际应用中面临诸多问题困扰。从液体菌种制备技术方面涉及的设备选型、菌株选育、工艺控制以及污染发生等环节,研究问题的发生原因与相应的解决办法。

磁性液体水平传感器的实验研究

制备满足磁性液体水平传感器应用要求的磁性液体,以及设计合理可行的实验模型是进行磁性液体水平传感器研究的实验基础.通过自行制备煤油基磁性液体,用于自行设计的磁性液体水平传感器实验模型,分析并探讨磁性液体水平传感器用煤油基磁性液体的制备工艺,及磁性液体水平传感器实验模型设计参数的可行性.实验证明磁性液体的制备工艺完全适用于磁性液体水平传感器的研究,实验模型的参数设计是可行的,实验结果验证了建模的理论依据.

Dissolution Improvement of Cisapride by Solid Dispersion with HPMC

To prepare a solid dispersion of cisapride with hydroxypropylmethyl cellulose(HPMC E5 LV) as carrier for the purpose of accelerating the in vitro drug release by means ofimproving the solubility of the model drug. Methods Alcohol and simulated gastric fluid (SGF) wereused to dissolve cisapride and HPMC in order to make the model drug dispersed homogeneously in thecarrier. The HPMC-cisapride solid dispersion was then obtained by conventional solvent evaporationmethod. Powder X-ray diffraction (XRD) was used to measure the diffraction peaks of pure carrier,pure cisapride, physical mixture of HPMC with cisapride (4:1), and HPMC-cisapride solid dispersion(4:1) to confirm the crystal existence. The solubility of pure drug and HPMC-cisapride soliddispersion was measured with water, SGF and simulated intestinal fluid (SIF) . The in vitro drugreleases of the sustained release tablet prepared with pure cisapride or HPMC-cisapride soliddispersion were investigated with water and SGF as media, respectively. Results No diffraction peakswere found by X-ray diffraction in the HPMC-cisapride solid dispersion (4:1), indicating that thedrug existed in an amorphous form at that drug-carrier ratio. Compared with the pure drug, thesolubilities of HPMC-cisapride solid dispersion are increased by 239.4% in SGF, 132.6% in water, and117.9% in SIF. According to the in vitro drug release, the sustained release tablet prepared withHPMC-cisapride solid dispersion had a faster drug release than did that prepared with pure drug. Thein vitro drug release profiles were found to comply with Higuchi's rule. Conclusion The in vitrodrug release of the sustained release tablet made by HPMC-cisapride solid dispersion is improvedowing to the increased drug solubility.

Preparation of copper nanoparticles modified with [BMIm]BF_4 ionic liquid

Copper nanoparticles was prepared by ascorbic acid reducing CuC12 solution modified with [ BMIm ] BF4 ionic liquid. The size of copper nanoparticles was obviously affected by the concentration of Cu2＋ . The diameter of nanoparticles was smaller than 10 nm when the Cu2＋ concentration was smaller than 2× 10.2 moL/L. The pH and temperature of reductive reaction had no obvious effect on the size of copper nanoparticles.

Hydroxyapatite Coatings on Titanium Prepared by Electrodeposition in a Modified Simulated Body Fluid

Hydroxyapatite coatings were directly prepared on anodized titanium by electro-deposition method in a modified simulated body fluid.The configuration,structure and bioactivity of the coating were investigated with scanning electron microscopy(SEM),X-ray diffraction analyzer(XRD)and Fourier transform infrared spectros-copy(FTIR)techniques.The results demonstrated that pure and homogeneous hydroxyapatite coating can be obtained without any post-treatment.The prepared coating showed good bioactivity in simulated body fluid(SBF).The time required for a fully covered dense hydroxyapatite coatings was 4 days immersion in SBF.

Application of Choline Chloride·xZnCl2 Ionic Liquids for Preparation of Biodiesel

The inexpensive and moisture-stable Lewis-acidic ionic liquids were prepared and applied for transesterification of soybean oil to biodiesel.The influences of molar ratio of methanol to soybean oil,reaction temperature and amount of ionic liquids were investigated.The transesterification of soybean oil to biodiesel catalyzed by choline chloride·xZnCl2 ionic liquids showed many advantages such as mild conditions and lower cost.On the other hand,the non-ideal yield and complicated separation between biodiesel and soybean oil were also investigated and analyzed.The improvement on the systems of choline chloride·xZnCl2 was proposed for further investigation.

Preparation of lactic acid from glucose in ionic liquid solvent system

A new reaction system was designed to economically convert glucose to lactic acid environment-friendly. Hydrophobic ionic liquids were chosen as solvent that can promote the decomposition reaction of glucose, and the catalytic performance of the solid bases was evaluated. Both the reaction temperature and time can affect the yield of lactic acid. A high yield （97%） of lactic acid was achieved under the optimal reaction condition. The IH NMR spectra and HPLC-MS were used to identify the formation of the lactic acid and variations of ionic liquid. It is found that ionic-liquids have a unique solvent effect for glucose and bases. Water can be used as solvent to extract calcium lactate. This shows a great potential of hydrophobic ionic liquids in the solid bases catalyzed reaction that is limited by the weak solubility of solid bases in organic and water solution.

Preparation and characterization of monodisperse zirconia spherical nanometer powder via lamellar liquid crystal template method

Cubic phase spherical zirconia nano-powder was prepared by a direct template route in the lamellar liquid crystal formed by polyoxyethylene tert-octylphenyl ether(Triton X-100)/sodium dodecyl sulfate(SDS)/H_2O.The precursor powder and zirconia powder were characterized by XRD,FT-IR,TG/DSC,TEM,and SEM methods.Results show that the stability of the lamellar liquid crystal is controlled by NH_3·H_2O concentration.The size of nanoparticles is greatly affected by NH_3·H_2O and ZrOCl_2·8H_2O concentrations.The zirconia nanoparticles show narrow particle size distribution of 10-30 nm.

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.

Preparation and characterization of Mo-Cu nanocomposite powders by chemical liquid reduction process

A novel chemical liquid reduction process was employed to prepare nanosized Mo-Cu powders. The precipitates were first obtained by adding ammonium heptamolybdate （（NH4）6Mo7024·4H2O） solution into excess hydrazine hydrate solution, and then mixed the copper chloride solution. The precipitates were subsequently washed, dried, followed by reducing in H2 atmosphere to convert into Mo-Cu composite powders. The composition, morphology and particle size of the Mo-Cu composite powders were characterized by the XRD, SEM and TEM. The effects of the chemical reaction temperature and the magnetic stirring on the morphology of the Mo-Cu powders were also studied. The results show that Mo-Cu powders produced by the chemical liquid reduction process are nearly spherical shape and dispersive distribution state, with particle size ranging from 50 to 100 nm. The chemical reaction temperature and magnetic stirring will change the particle feature of the powders. Because of the Cu3M0209, the reduction process in H2 is the one-stage reduction from the precipitates to the Mo-Cu composite powders.

Fabrication of compact and stable perovskite films with optimized precursor composition in the fast-growing procedure

The fast-growing procedure （FGP） provides a simple, high-yield and lead （Pb）-release free method to prepare perovskite films. In the FGP, the ultra-dilute per- ovskite precursor solution is drop-cast onto a hot （-240℃） substrate where a perovskite film grows immediately ac- companied by the rapid evaporation of the host solvent. In this process, all the raw materials in the precursor solution are deposited into the final perovskite film. The potential pollution caused by Pb can be significantly reduced. Proper- ties of the FGP-processed perovskite films can be modulated by the precursor composition. While CH3NH3CI （MACI） affects the crystallization process and leads to full surface coverage, CH（NHz）2I （FAI） enhances the thermal stability of the film. Based on the optimized precursor composition of PbI2.（1-x）FAI.xMACI, x=0.75, FGP-processed planar het- erojunction perovskite solar cells exhibit power conversion efficiencies （PCEs） exceeding 15% with suppressed hysteresis and excellent reproducibility.

Solution-processed amorphous gallium-tin oxide thin film for low-voltage, high-performance transistors

Gallium-tin oxide(GTO) semiconductor thin films were prepared by spin-coating with 2-methoxyethanol as the solvent. Their crystal structures, optical transparency,chemical states and surface morphologies, along with the electrical properties, were dependent on Ga contents and annealing temperatures. The optimized GTO channel layer was applied in the high-k Al2O3 thin film transistor(TFT) with a low operation voltage of 2 V, a maximum field-effect mobility of 69 cm^2 V^-1 s^-1, a subthreshold swing(SS) of 76 mV dec^-1, a threshold voltage of 0.67 V and an on-off current ratio of 1.8×10^7. The solution-processed amorphousGTO-TFTs would promote the development of low-consumption, low-cost and high performance In-free TFT devices.

Directing nucleation and growth kinetics in solution-processed hybrid perovskite thin-films

A heightened understanding of nucleation and growth mechanisms is paramount if effective solution processing of organic-inorganic perovskite thin-films for optoelectronic applications is to be achieved. Many fabri- cation techniques have been utilized previously to develop high-performance perovskite layers but there remains an absence of a unifying model that describes accurately the formation of these materials from solution. The present study provides a thorough analysis of nucleation and growth kinetics underpinning the development of hybrid organic-in- organic perovskite thin-films. Through precise control of the perovskite growth conditions the spacing of heteroge- neous nucleation sites was varied successfully from several hundred nanometers to several hundred microns. The crystalline regions surrounding these nuclei were found to comprise clusters of highly-oriented crystal domains exceed- ing 100 pm in diameter. However, no beneficial correlation was found between the size of these well-oriented grain-clus- ters and the optoelectronic performance. The formation of the perovskite microstructure features characteristics of both classical and non-classical growth mechanisms. The insights into perovskite thin-film growth developed by the present study provide clear implications for the development of future hybrid perovskite microstructures.

Proteomic study provides new clues for complications of hemodialysis caused by dialysis membrane

The complications of hemodialysis accompanied the hemodialysis and threaten the patients’life.Besides the loss of nutrient substance,such as amino acid and vitamin,we found new clues that the adsorbed proteins on common-used polysulfone-based dialysis membrane might be the reason according to the qualitative proteomic study by ionic liquid assisted sample preparation method.Our results indicated that the adsorbed proteins on the membrane were related with complement activation,blood coagulation,and leukocyte-related biological process.The quantitative proteome further demonstrated some significant changes of signal proteins in the post-dialysis plasma after the hemodialysis,such as beta-2-microglobulin and platelet factor-4,which would further verify these new clues.

Large-scale fabrication of field-effect transistors based on solution-grown organic single crystals

A simple solution processing method was de- veloped to grow large-scale well-aligned single crystals in- cluding 6,13-bis（triisopropylsilylethynyl）pentacene （TIPS- pentacene）, anthracene, tetracene, perylene, C6o and tetra- cyanoquinodimethane. As pinned by a solid needle, a droplet of semiconductor solution dried into single-crystal arrays on a 1 cm×2 cm substrate. TIPS-pentacene was used to demonstrate the fabrication of hundreds of field- effect transistors （FETs） with the hole mobility as high as 6.46 cm^2 V^-1.s^-1. As such, this work provides a high- throughput, yet efficient approach for statistical examination on the FET performance of organic single crystals.