A penta‐band hybrid fractal MIMO antenna for ISM applications

A miniature two‐element MIMO multiband planar patch antenna with potential applications in the ISM bands is presented. The elements of the antenna have been designed using a novel hybrid fractal geometry based on an altered Dragon Curve and the Inverted Koch. Reduced antenna dimensions are obtained with acceptable performance even at lower frequency ranges. The antenna elements are placed adjacent to each other with a very small spacing of 0.004 λ₀ (λ being the free space wavelength of 433 MHz), confining the antenna dimensions to 51 × 50 mm². The antenna resonates at the 433 MHz (ISM), 2.4 GHz (ISM), 3.9 GHZ (Fixed Satellite), 4.7 GHz (UWB) and 5.8 GHz (ISM) frequency bands. The antenna exhibits |S₁₁| ≤ ?10 dB, |S₂₁| ≤ ?16 dB, an ECC ≤ 0.01 for all operating frequencies, with circular polarisation at the 2.4 GHz and 5.8 GHz bands and linear polarisation at the others. The simulated structure was fabricated and tested, with the simulated and measured results displaying acceptable agreement.     

天安门城楼外檐金龙和玺彩画（本期中心彩色插页）说明

天安门城楼重油饰彩画修缮按原明清时期的传统彩画制度，外檐梁枋彩画装饰了金龙和玺。和玺彩画为明清彩画等级中最高制度。金龙和玺以金龙为此种彩画的装饰题材。它为沥粉片金加攒退做法。各主要纹路部位的划分安排基本上同龙草和玺彩画，各主要线路均沥粉贴金，各种主要线路都施以晕色。     

荆州太晖观建筑艺术初探

通过对太晖观主体建筑勘察测绘,从一个侧面浅析该建筑的石雕、砖雕、木雕艺术造型,展示太晖观建筑艺术,体现我国古代劳动人民的聪明才智和伟大创造力。     

武当山遇真宫新发现的龙虎殿明代早期彩画考证及原状研究 #

建筑彩画为保护木构而设,常因损坏不断更新。因此,年代越久越难以留下。明代官式彩画在中国彩画发展史上具有承前启后的重要作用,现存数量稀少。本文通过考察湖北武当遇真宫,在现场勘测的基础上,采取类型学方法研究,认为遇真宫龙虎殿彩画无论是大线构图、纹饰造型还是设色方式都具有明代早期特征,属于新发现的明代早期官式旋子彩画实例。同时通过与相似案例比对,辨认其纹饰造型,考证 并探究其原貌特征,以这一新发现的珍贵案例,丰富现有明代官式彩画的研究。     

High surface area and mesoporous activated carbon from KOH-activated dragon fruit peels for methylene blue dye adsorption:Optimization and mechanism study

In tnis study,an alternative precursor for production of activated carbon was introduced using dragon fruit(Hylocereus costaricensis) peel(DFP).Moreover,KOH was used as a chemical activator in the thermal carbonization process to convert DFP into activated carbon(DFPAC).In order to accomplish this research,several approaches were employed to examine the elemental composition,surface properties,amorphous and crystalline nature,essential active group,and surface morphology of the DFPAC.The Brunauer-Emmett-Teller test demonstrated a mesoporous structure of the DFPAC has a high surface area of 756.3 m~2·g~(-1).The cationic dye Methylene Blue(MB) was used as a probe to assess the efficiency of DFPAC towards the removal of MB dye from aqueous solution.The effects of adsorption input factors(e.g.DFPAC dose(A:0.04-0.12 g·L~(-1)), pH(B:3-10),and temperature(C:30-50℃)) were investigated and optimized using statistical analysis(i.e.Box-Behnken design(BBD)).The adsorption kinetic model can be best categorized as the pseudo-first order(PFO).Whereas,the adsorption isotherm model can be best described by Langmuir model,with maximum adsorption capacity of DFPAC for MB dye was 195.2 mg·g~(-1) at 50℃.The adsorption mechanism of MB by DFPAC surface was attributed to the electrostatic interaction,π-π interaction,and H-bonding.Finally,the results support the ability of DFP to be a promising precursor for production of highly porous activated carbon suitable for removal of cationic dyes(e.g.MB).     

Gut microbiota modulation and immune boosting properties of prebiotic dragon fruit oligosaccharides

This is the first report of the evaluation of suitability for consumption of dragon fruit oligosaccharide (DFO) and its efficacy on gut microbiota modulation and in boosting the gut immune response in rats. The DFO produced significantly increased faecal bifidobacteria and lactobacilli but decreased bacteroides and clostridia. The DFO also showed immune-response boosting properties by significantly increasing the plasma immunoglobulin A and G concentrations. In addition, it was confirmed by blood chemistry analysis and histology of the colon of the rats that DFO is suitable for the consumption. These results suggest that DFO is a potentially novel source of prebiotic ingredients with probiotic-stimulation and immune boosting properties.     

龙舟意象·文化传承——谈华侨大学厦门校区龙舟训练馆设计

华侨大学厦门校区龙舟训练馆是学校在国侨办的批示下,为更好地发展中华才艺(龙舟)培训基地而筹划设计的专业训练场馆。本文尝试通过对其设计背景、设计思路的分析,说明其如何在满足基本功能需求的同时,达到传递中华文化并体现侨校特色的特殊要求。     

Mechanical Means of Enhancing Drying Rates: Effect on Drying Kinetics and Quality

ABSTRACT

The effect of various pretreatments on drying kinetics as well as quality parameters of selected vegetables and fruits was studied experimentally in a convective dryer. The pretreatments tested include application of pinholes and drilled holes of different diameters and densities, blanching and freezing. Potato, cassava, dragon fruit and red chilli were used as the sample drying materials. As expected, increase of the diameter and density of the holes under fixed drying conditions increased the drying rate. Samples with drilled holes showed better drying performance than those with pinholes. The improvement of the drying rate was found to be dependent on the physical properties and the initial moisture content of the material. Results show that the drying performance of the products that possess a skin of low moisture diffusivity, such as chilli, can be improved significantly by blanching and making perforations in the skin. Overall changes of color and volume shrinkage during drying of the samples with and without holes were similar. The effect of different modes of heat input, such as convection, conduction and radiation, on the drying performance of the treated samples was also experimentally investigated. On-off type controllers were used to regulate the power of the heaters and maintain the product temperature within a range of pre-set values. Convection combined with radiation displayed the highest drying rate.     

基于创意婚庆产业空间组织的城市设计——以南阳龙城城市设计为例

考察我国当前结婚人口状况与婚庆产业之规模,针对当代新婚人士崇尚创意婚庆的特点,该文提出在有一定人口规模支撑的城市营造婚庆产业集聚区——婚庆城的设想;同时对婚庆城的选址与功能特点进行了深入探讨。最后结合南阳龙城的城市设计,从婚庆主轴、布局结构、婚仪环境、婚纱影视、主题婚庆产品、婚庆超市等6方面阐述了创意婚庆产业之空间组织方面的设想。