基于VegaPrime的飞行器视景仿真关键技术研究

给出了某型飞行器飞行视景仿真系统的结构框架,提出了基于OpecGL图形编程绘制二维窗口实现二三维联动的方法,该方法简单且效率高．采用嵌套使用碰撞检测器的方法,实现了复杂碰撞检测的预检测,降低了系统的计算量．在经典粒子系统的原理上,用纹理贴图代替粒子实现了特殊效果模拟,节省了系统资源开销．     

葱姜蒜及其复配物的抗菌性能研究

文章对洋葱、生姜和大蒜及其复配物的抗菌性能进行了研究.结果表明:大蒜的抗菌性能最好,洋葱和生姜的抗菌性能较差;并且葱姜蒜间存在抗菌的协同作用和拮抗作用.     

乳酸菌及乳酸菌发酵食品

介绍了乳酸菌的生理功能、乳酸发酵食品及其开发应用前景。     

Determination of protoberberine alkaloids in Coptidis Rhizoma by novel extraction and high-performance liquid chromatography

An alternative, effective, and solvent-free microextraction method has been developed using weighing paper as the adsorbent for five protoberberine alkaloids from the methanolic extract of Coptidis Rhizoma (C. Rhizoma). Several variables influencing extraction efficiency were optimized. 1.0?×?1.0?cm glassine weighing paper was employed for the isolation of the analytes followed by high-performance liquid chromatography. Under the optimum conditions, the limits of detection were between 0.2 and 0.4?ng/mL with enrichment factors from 41–47. The calibration curves were linear across the concentration ranges examined with correlation coefficients exceeding 0.992. All relative standard deviations were less than 10.0%. The method was employed for the determination of the analytes in C. Rhizoma. Berberine, palmatine, coptisine, epiberberine, and jatrorrhizine were present at concentrations between 9.62?±?0.87?mg/g and 0.48?±?0.05?mg/g.     

Comparison of encapsulation properties of major garlic oil components by hydroxypropyl β-cyclodextrin

The major garlic oil (GO) components were encapsulated by hydroxypropyl β-cyclodextrin (HP-β-CD), and their encapsulation properties were compared in this study. Our results showed that the optimal conditions for the GO encapsulation were as follows: weigh ratio at 12:88 (GO: HP-β-CD), pH at 5.0, and inclusion time at 4 h. Furthermore, results from the phase solubility curves indicated that two components of diallyl disulfide (DADS) and diallyl trisulfide (DATS) had higher water solubility caused by HP-β-CD and that DATS-HP-β-CD complex had higher stability constant (K _1:1 = 6.702 × 10⁵) and more significant change in free energy ( \Updelta G_\textCOMP^* \Updelta G_{\text{COMP}}^{*}  = −3.496 × 10⁴) than DADS-HP-β-CD. These findings indicated that DATS was better suited to be encapsulated by HP-β-CD compared to DADS. The result finally obtained from gas chromatography–flame ionization detector (GC–FID) confirmed the easier inclusion properties of DATS by HP-β-CD.     

Highly dispersed Pt nanoparticles supported on poly(ionic liquids) derived hollow carbon spheres for methanol oxidation

Hollow carbon spheres (HCSs) are prepared using poly(ionic liquids) (PILs) as a carbon precursor and monodisperse silica particles as a template for the first time. The ILs form a uniform polymer coating on the template surface after polymerization. Carbonization of the coating and the subsequent removal of the template produces porous carbon spheres with a hollow structure. The HCSs possess a high surface area, good conductivity, and porosity suitable for mass transport, and they can be used as a support for Pt electrocatalysts. Pt nanoparticles with an average size of 2.8 nm are homogeneously distributed onto the HCSs. The high surface area and unique structure facilitates the fine dispersion of Pt nanoparticles. The obtained Pt/HCSs exhibit a significant catalytic activity for the oxidation of methanol.     

Analysis of flavour compounds in beer with extruded sorghum as an adjunct using headspace solid‐phase micro‐extraction and gas chromatography–mass spectrometry

Sorghum is a widely used adjunct that is used in the production of beer and increasingly affects beer flavour as the amount added increases. The aim of this work was to establish a simple, solvent‐free technique, without derivatization, to analyse flavours and typical volatile compounds present in extruded and unextruded sorghum beer, and to compare the flavour differences of the two types of beer. Headspace solid‐phase micro‐extraction gas chromatography–mass spectrometry was used to determine the flavours in the two beers and eight typical volatile compounds were quantified using GC. Forty‐five flavour compounds were identified and quantified in extruded white sorghum beer, while 31 flavour compounds were identified in unextruded white sorghum beer. Extruded or unextruded white sorghum can be used to produce ale beer, but the primary flavour content in the extruded white sorghum beer was higher than in the unextruded white sorghum beer. Copyright © 2016 The Institute of Brewing & Distilling     

Influences of sodium species with different occurrence modes on the thermal behaviors and gas evolution during pyrolysis of a sodium-rich Zhundong subbituminous coal

The Zhundong coal (ZDC) with a huge proven reserve is featured by high abundance of sodium species which behaves actively in the thermal conversion of it. In this work, to better understand the multiple roles of sodium species in coal pyrolysis, influences of sodium species with different occurrence modes on the thermal behaviors and gas evolution during pyrolysis of a sodium-rich ZDC were investigated. Raw coal was initially demineralized by dilute hydrochloric acid. Subsequently, sodium species was reloaded into the demineralized sample by ion-exchanged or immersed method. For quantitative analyses, a thermo-gravimetric analyzer coupled with a mass spectrometer was used to record the weight loss of different samples and the ever-changing amount of gaseous products in pyrolysis. The results show that the structural change induced by demineralized and ion-exchanged treatment is mainly reflected in the band intensity of carboxyl groups. In pyrolysis of ZDC, total volatile matters yield has a close relation with the occurrence modes of sodium species. It is proved that water-soluble sodium species has catalytic effects on the thermal-cracking reactions, whereas exchangeable sodium species tends to facilitate char-formed reactions. Compared with exchangeable ones, water-soluble sodium species can be also volatilized more easily in pyrolysis. As for gas evolution, exchangeable sodium species can obviously affect formation of CO through char gasification and it is also favorable to formation of hydrogen radicals. Moreover, due to the low sulfur content in ZDC, the intensity of H₂S released from all samples is extremely weak, which suggests that ZDC is a suitable feedstock for clean coal utilization.     

乳液聚合法制备石蜡基相变储能材料及热物性研究

将石蜡真空浸渍于膨胀蛭石中,以其共同作为内相,丙烯酰胺水溶液作为外相,制得水包油乳液,引发剂使外相聚合,得到形状稳定的复合相变储热颗粒。测试结果表明：乳化剂和膨胀蛭石分别为石蜡质量的6%和2%时,熔融焓数值为128.79 J/g,石蜡的包覆率为72.80%;复合颗粒的形状是表面规整的球体,颗粒大小均匀;经过100次循环后,熔融焓只降低2.18%;复合颗粒在470 ℃以下有较好的热稳定性。膨胀蛭石与聚丙烯酰胺对石蜡的二次封装可有效提高复合体系防泄露能力,具有可靠的储能和温度调节性能。     

益生菌抗氧化活性及菌体抗氧化相关成分的分析

目的比较乳杆菌、双歧杆菌、嗜热链球菌和乳酸乳球菌的抗氧化活性,分析抗氧化活性较高菌株内与抗氧化相关的成分。方法采用清除DPPH自由基、清除羟自由基以及抗脂质过氧化能力3种方法评价40株益生菌的抗氧化活性,选出抗氧化活性较高的菌株分析其超氧化物歧化酶(SOD)、谷胱甘肽(GSH)和总巯基化合物(TTG)的含量。结果所比较的40株益生菌的抗氧化能力差别较大,既具有种属特异性,又具有菌株特异性;7株嗜热链球菌和11株乳酸乳球菌中的SOD活性最高[(平均分别为124.02U/mg(蛋白质)和107.10U/mg(蛋白质)]、2株双歧杆菌中GSH的含量最高(平均为311.03μmol/L细胞破碎液),所分析的菌株中TTG含量均较高。研究结果表明,实验菌乳酸乳球菌清除自由基能力最强,其次是嗜热链球菌,所试验的乳杆菌和双歧杆菌最弱;SOD对益生菌的抗氧化起主要作用;GSH的存在因种属和菌株的不同而差别较大;TTG对益生菌的抗氧化起了积极作用。