Preparation technology of ultra-fine powders of Auricularia auricular

Conventional mechanical method and mechanical method combined with vacuum freeze-drying technology were used to make the ultra-fine powders of edible fungus (Auricularia auricular). The content of basic nutrients, amino acid, micro structure and their properties of raw edible fungus and the edible fungus powders obtained with the two methods were analyzed and compared. The granularity size and micro-structure of the pulverized samples were analyzed by SEM and TEM technology. The average granularity size of the edible fungus powder obtained with mechanical method was 1–5 μm, while that obtained with mechanical method combined with vacuum freeze-drying process was 0.5–1 μm. The ultra-fine powders of edible fungus obtained with the two methods had better water recovery capability and quality, and their preserving time was longer than that of raw edible fungus. All the properties of the ultra-fine powders of edible fungus obtained with the vacuum freeze-drying technology were evidently superior to that of the conventional mechanical method. Keywords Auricularia auricula - Edible fungus - Ultra-fine powders - Vacuum freeze-drying CLC number TS205 Document code B Biography: YANG Chun-yu (1975), female, Ph. D. in Engineering Technology Center of Forestry and Wood Workine, Machinery, Northeast Forestry University, Harbin 150040, P. R. China.Responsible editor: Zhu Hong

Optimal Conditions for Preparing Ultra-Fine CeO_2 Powders in A Submerged Circulative Impinging Stream Reactor

Cerium carbonate powders were produced in a submerged circulation impinging stream reactor （SCISR） from Ce（NO3）3· 6H2O. NH4HCO3 was used as a precipitant in the reaction. Cerium carbonate powders were roasted to produce ultra-fine cerium dioxide （CeO2） powders. The optimal conditions of such production process were obtained by orthogonal and one-factor experiments. The results showed that ultra-fine and narrowly distributed cerium carbonate powders were produced under the optimal flowing conditions. The concentrations of Ce（NO3）3 and NH4HCO3 solutions were 02,5 and 0.3 mol · L^-1, respectively. The concentration of PEG4000 added in these two solutions was 4 g · L^-1. The stirring ratio, reaction temperature, feeding time, solution pH, reaction time and digestion time were 900 r · min^- 1,80 ℃, 20 min, 5 - 6, 5 min and 1 h, respectively. The final product, CeO2 powders, was obtained by roasting the produced cerium carbonate in air for 3 h at 500 ℃. The finally produced CeO2 powders were torispherical particles with a narrow size distribution of 0.8 -2.5 μm. The crystal structure of CeO2 powders belonged to cubic crystal system and its space point 5 group was OH^5-FM3M. Under optimal conditions, powders produced by SCISR were finer and more narrowly distributed than that by Stirred Tank Reactor （STR）.

DYNAMIC RHEOLOGICAL BEHAVIOR OF POLYPROPYLENE FILLED WITH ULTRA-FINE POWDERED RUBBER PARTICLES

Dynamic rheological characteristics of polypropylene (PP) filled with ultra-fine full-vulcanized powdered rubber (UFPR) composed of styrene-butadiene copolymer were studied through dynamic rheological measurements on an Advanced Rheometric Expansion System (ARES). A specific viscoelastic phenomenon, i.e. 'the second plateau', appeared at low frequencies, and exhibits a certain dependence on the amount of rubber particles and the dispersion state in the matrix. This phenomenon is attributed to the formation of aggregation structure of rubber particles. The analyses of Cole-Cole diagrams of the dynamic viscoelastic functions suggest that the heterogeneity of the composites is enhanced on increasing both particle content and temperature.

An improved sodium silicate binder modified by ultra-fine powder materials

This paper presents a new method of modifying sodium silicate binder with ultra-fine powders. The sodium silicate binder modified by ultra-fine powder A and the organic B can reduce the addition amount of the binder. The results indicate that the 24 h strength has increased by 39.9% at room temperature and the residual strength has decreased by 30.7% at 800℃, compared to the conventional sodium silicate. An available material to improve the moisture resistance was also found by adding about 2% more inorganic C, and it can increase the moist strength by 20%. In the end, the microanalyses are given to explain the modifying machanism, i. e., the ultra-fine powder A can refine the sodium silicate binder to avoid holes in the binder bond, which can increase the 24 h strength at room temperture, and can lead to more cracks in the bond after the molding sand is heated to 800℃. This is because of the stress caused by the new eutectic complex of modified sodium silicate binder.

Hydrogen Reduction:A Novel Method of Synthesizing Ultra-fine Chromic Oxide Powder

The ultra-fine chromic oxide powder was prepared by a novel gas-solid reduction reaction.Na2CrO4 was firstly reduced with hydrogen at 400-600 ℃.The obtained reduction products,mainly the mixture of NaCrO2 and sodium hydroxide（NaOH）,were converted into chromic oxide through hydrolysis followed by calcination.The obtained chromic oxide product was characterized by powder X-ray diffraction（XRD） and SEM.The results show that the hydrolysis process of sodium chromite is the key step and lower reduction temperature helps intensify the hydrolysis process.

Strengthening of HT250 by modified ultra-fine ceramic powders

In this study, three kinds of modified ultra-fine ceramic powders marked A, B and C, which were prepared by each of three different modifiers mixing with a commercial SiC, were added to HT250 cast iron, respectively, and the effects of the modified ultra-fine ceramic powders on microstructure, mechanical properties and wear resistance were studied. Metallographic examination, tensile test, scanning electron microscopy, and three-dimensional surface topography were applied to analyze and compare the samples containing modified powder with the original samples. The results showed that the most obvious modification effect among the powders was seen in the sample containing powder A, with the graphite and eutectic cells being refined, the tensile strength being increased by 36.9%, and the wear resistance being improved by 45.5% and 47.2% under loads of 150 N and 300 N, respectively. The improvements of mechanical properties and wear resistance in the HT250 cast iron with the modified ultra-fine ceramic powders were attributed to the synergistic effect of the grain refinement with the powder acting as a hard particle phase and the lubrication by the graphite.

Preparation of Ultra-fine Salbutamol Sulfate Particles by Reactive Precipitation and Characterization of Dry Powder Inhalant

The preparation of ultra-fine particles of salbutamol sulphate （SS） was accomplished with a reactive precipitation pathway, in which salbutamol and sulphuric acid were Used as reactants with the solvents of ethanol.The effects of sulphuric acid concentration, reaction temperature, stirring rate, and reaction time onthesize of the particle were investigated. A binary mixture composed of lactose and SS was prepared to evaluate SS. The results showed that ultra-fine SS particles with controlled diameters ranging between 3 μm and 0.8 μm and with a narrow distribution could be achieved. The morphology consisting of clubbed particles wassuccess.fully obtained. The purity of the particles reached above 98% with-UV detection. The dose- of dry powder inhalation was obtained by blending the particles with recrystallized lactose, which acted as a carrier. The deposition quantity of the drug in breathing tract was estimated using a twin imPinger apparatus. Compared with the Shapuer powder （purchased in the market）, the results showed that SS_particles had more quantifies.subsided in simulative lung.. _

Study on Key Techniques for High-quality and High-yield Cultivation of Ganoderma lucidum Spore Powder

Comparative test of 4 Ganoderma lucidum varieties from different sources showed that the mycelium of Chizhi 1 grew fast with thick and dense hyphae,round and solid cap,and high spore powder yield.Chizhi 1 was proved to be an excellent variety because of its strong resistance and high spore powder yield.Different cultivation materials were chosen and combined to form 3 cultivation formulations.The results showed that Formulation(3),in which basswood was soaked in nutrient solution for 24 h,presented fast mycelial growth and high spore powder output,and therefore was proved to be a high-yield formulation of Ganoderma lucidum spore powder.

CALCULATION AND EXPERIMENTAL INVESTIGATION OF ELECTRIC FIELDS INDUCED BY ELECTRODES IN ELECTROSTATIC CHARGED POWDER SPRAYING TECHNIQUE

Electric fields induced by ring and pin electrodes in electrostatic charged powder sprayingtechnique are analysed. The fundamental formulae to deseribe these fields have been built up. Theseformulae could be used to design electrostatic charged podwer spraying system. The chargingeffectiveness of ring and pin electrode is experimentally investigated and compared each other. Theperformance of ring electrode is better than that of pin electrode.

Preparation of Well Dispersed and Ultra-Fine Ce(Zr)O_2 Mixed Oxide by Mechanochemical Processing

Ultra-fine CeO_2-ZrO_2 mixed oxide was successfully synthesized by wet-solid phase mechanochemical processing, Ce_2(CO_3)_3·8H_2O, ZrOCl_2·xH_2O and ammonia were used as reactants. It is found that the crystalline Ce_2(CO_3)_3·8H_2O and ZrOCl_2·xH_2O are changed to amorphous cerium and zirconium hydroxide precursor after milling with ammonia, and Ce_(0.15)Zr_(0.85)O_2 mixed oxide with pure tetragonal phase structure and medium particle size(D_(50))less than 1μm is formed by calcining precursor over 673 K. The XRD patterns indicate that the crystal unite size increases with rising calcining temperature due to crystal growth. However, the particle size and BET surface area of the Ce(Zr)O_2 mixed oxide decreases with rising calcining temperature, which may be attributed to the contract of particles and the vanish of holes inside grains.

A Novel near Net-Shape Technique for P/M Parts with Large H/D Ratio

In order to overcome the shortcomings of conventional hot pressing, a novel near net-shape technique, called radial hot pressing, for P/M parts with large height-to-diameter (H/D) ratio was introduced. Effects of processing parameters on the microstructures and density of P/M TiAl base alloy valves were studied. Results show that the radial hot pressing is an effective technique for manufacturing valves with a H/D ratio of about 10:1, and the perfect joint interface between the Mo sheet and the parts is helpful for subsequent HIPing.

逍遥散方质量控制技术研究进展

逍遥散方为治疗妇科诸疾、郁证的代表方,由柴胡、当归、茯苓、白芍、白术、甘草、生姜、薄荷8味饮片组成,具有疏肝解郁、养血健脾的功效。文章就近10年来逍遥散方在制备工艺、鉴别技术、含有量测定等方面出现的新方法、新技术进行归纳总结,以期为该方制剂的质量控制及进一步开发应用提供科学依据。

基于GA的灰铸铁表面激光熔覆316 L工艺参数优化

为了提升HT250灰铸铁材料的综合性能,采用遗传算法对多目标工艺参数进行优化,得出相应经验参数组,在灰铸铁材料表面进行激光熔覆316L合金实验;采用数字化检测仪器,根据试样几何形状、宏观形貌、硬度等变化规律,得出最优工艺参数组。结果表明,当设置送粉速率为0.25 g/s、扫描速率为10 mm/s、激光功率为2800 W时,316L熔覆层表面几何形状最佳,宏观形貌好,洛氏硬度最大值达37.6 HRC,试样熔覆性能良好。这一结果综合提高了灰铸铁的各项性能,为灰铸铁产品磨损后的修复再利用提供实践参考。

无机工业固体废弃物高温热化学转化的基础研究

随着工业的持续发展,煤、油页岩、菱镁矿、铁矿等矿物资源的用量不断增加,产生大量无机工业固体废弃物,低效的固废处置方式造成了巨大的环境污染和资源浪费。基于常见典型工业固体废弃物的化学组成,结合热力学分析结果,提出一种工业固体废弃物高温热化学转化方法,直接将无机工业固体废弃物转化为高附加值材料。该高温热化学转化方法通过热力学分析确定理想的目标产物及反应温度,利用热质传递效率高和易于放大的流化床,使单一或多种固体废弃物混合物中的各化学成分间发生固-固高温热化学反应,制成所需的复相材料使用或经进一步加工制得具有更高附加值的终端产品。通过对菱镁矿浮选尾矿、硼泥、油页岩渣、铁尾矿、铝灰、煤矸石等多种固体废弃物实验,获得了相应的复相粉体材料,验证了该方法的可行性。同时,通过选择性混合多种固体废弃物,改变反应物组成,可以调控目标产物及其含量。实验结果表明,利用高温流态化热化学反应技术,无机工业固体废弃物可成功转化为高附加值产物。研究成果对实现无机工业固体废弃物的有效利用、减少资源浪费、保护生态环境、推动绿色、低碳和可持续发展提供了又一途径,也为相关固体废弃物的综合利用提供了具体数据支撑。

固体分散体制备技术及质量控制研究进展

【目的】从固体分散体(solid dispersions,SDs)制备技术和质量控制角度出发,揭示SDs技术在药物制剂领域的发展现状与挑战,旨在为SDs技术的进一步推广应用提供参考。【研究现状】总结熔融法、溶剂法、溶剂-熔融法、机械分散法等SDs制备技术,其中熔融法又包括传统熔融法、热熔挤出法、熔融凝聚、KinetiSol~?Dispersing、3D打印技术等,溶剂法又包括喷雾干燥、冷冻干燥、流化床干燥、超临界流体法、共沉淀法和静电纺丝法等;目前SDs制备技术存在需要使用有毒溶剂,可能导致药物热降解以及扩展性较差的问题。并归纳总结溶出度、药物和聚合物之间的相互作用、固态等SDs质量控制因素,重点强调一直被研究人员忽视的SDs粉体学性质。【展望】认为今后的研究重点应在开发或引入更多高效、无毒、稳定和扩展性好的SDs制备技术方面,并且要不断完善SDs的质量控制体系。

蒙药三子散多指标成分的含量测定

目的基于多指标成分含量测定结合灰色关联度分析(GRA)和逼近理想解排序法(TOPSIS)对蒙药三子散进行整体质量评价。方法采用高效液相色谱(HPLC)法测定15批三子散样品中诃子次酸、没食子酸、石榴皮鞣素、安石榴苷、jasminoside B、咖啡酸、柯里拉京、京尼平苷、诃子鞣酸、1,2,3,4,6-O-没食子酰葡萄糖、诃子林鞣酸、鞣花酸的含量,并对12种活性成分含量建立GRA和TOPSIS质量评价模型。结果12种指标成分在各自质量浓度范围内与峰面积呈良好的线性关系,r均不小于0.9995,平均回收率为96.72%~104.07%,RSD为1.4%~2.6%。GRA和TOPSIS分析结果基本一致,根据TOPSIS分析所得Ci值和GRA分析所得ri值可知,样品S1、S3、S4、S6、S10、S12、S14、S15排名前8。结论GRA-TOPSIS法排除了人为因素的干扰,提高了多指标决策分析的科学性与准确性,精确地反映了各评价方案之间的差距,可对三子散进行整体质量评价及优质资源筛选。

MicroLED全彩色微显示技术研究进展

随着可穿戴器件、增强现实、混合现实等新型显示产品的广泛应用和普及,新型显示技术在微小器件尺寸、高分辨率、高稳定性等性能方面又提出了更高的性能需求。基于微型发光二极管(microlight emitting diode,MicroLED)的微型显示器件具有低功耗、高稳定、长寿命和响应时间短等突出特征,其相关技术和产品近年来已被广泛应用于VR/AR眼镜、微投影设备等。在蓝光MicroLED矩阵像元芯片上通过集成色转换像元、超表面结构等可以构筑红、绿、蓝(RGB)三基色阵列发光器件,从而在有源驱动控制下实现动态的全彩色图像显示。文章总结了实现MicroLED全彩色微显示的主流技术,包括荧光粉色转换技术、量子点色转换技术和超表面结构集成技术,并进一步分析和对比了相关技术的优缺点,综述了MicroLED全彩色微显示器件的最新研究进展,探讨了相关技术在推动新型显示产业发展中的重要意义。

粉末涂料在汽车零部件涂装中的应用与发展

随着人们环境保护意识的增强和对绿色产品需求的提升,粉末涂料因其显著的环保优势、高效的涂装性能和卓越的耐用性,在汽车零部件涂装领域得到了日益广泛的应用。然而,粉末涂料在实际应用中仍面临一些挑战,如对涂装设备的特殊要求、粉末回收效率、涂层的均匀性以及对复杂零部件的涂装适应性等问题。本文阐述了粉末涂料的分类、特性及其在汽车零部件涂装中的应用现状和发展趋势。

紫薯复合营养餐粉的研制及冲调性能研究

以采用真空冷冻干燥技术制备的紫薯全粉为主要原料,添加燕麦粉、魔芋粉、脱脂奶粉及木糖醇等制备紫薯复合营养餐粉。紫薯复合营养餐粉的最佳配方为紫薯粉2.8 g(26.4%)、魔芋粉0.6 g(5.7%)、燕麦粉2.8 g(26.4%)、脱脂奶粉2.4 g(22.6%)、木糖醇2.0 g(18.9%)。紫薯复合营养餐粉的最佳冲调温度为75℃,最佳冲调水量(营养餐粉质量/冲调用水量)为1∶8,结块率为0.53%,润湿下沉性及速溶性较好。

Synthesis and Characterization of Nano-sized Boron Powder Prepared by Plasma Torch

Hydrogen thermal plasma jet was employed to prepare nano-sized boron powder with hydrogen reduction of BCI3. The maximum yield of nano-sized boron powders was about 50% with the operational conditions of H2/BCl3 of 4.5：1, total feed of 4.9 m3/h, and plasma power of 25 kW. The samples were analyzed by X-ray diffraction （XRD）, field emission scanning electron microscopy （FE-SEM）, and inductively coupled plasma - mass spectrometry （ICP-MS）, inductively coupled plasma - atomic emission spectrometry （ICP-AES）, inductive combustion infrared absorption （ICIA） and infrared thermal conductivity of oxygen and nitrogen analyzer （ITCA）. The results show that the boron powders have different crystal structures with higher dispersion and purity. The average diameter is about 50 nm, and the purity is 90.29% or so. This new technology can use simple process to produce high quality boron powders, and is feasible for industrial production.