Enabling electrically tunable radio frequency components with advanced microfabrication and thin film techniques

Multi-function,multiband,cost-effective,miniaturized reconfigurable radio frequency(RF)components are highly demanded in modern and future wireless communication systems.This paper discusses the needs and implementation of multiband reconfigurable RF components with microfabrication techniques and advanced materials.RF applications of fabrication methods such as surface and bulk micromachining techniques are reviewed,especially on the development of RF microelectromechanical systems(MEMS)and other tunable components.Works on the application of ferroelectric and ferromagnetic materials are investigated,which enables RF components with continuous tunability,reduced size,and enhanced performance.Methods and strategies with nano-patterning to improve high frequency characteristics of ferromagnetic thin film(e.g.,ferromagnetic resonance frequency and losses)and their applications on the development of fully electrically tunable RF components are fully demonstrated.

Application of Filming Technique in the DUS Test for PVP Information

As the great progress has appeared in the field of protection of new varieties of plants, the standardization of the DUS （Distinctness, Uniformity, Stability） test procedure has become more important. However, the specification of filming technique plays an important role in the DUS test of new varieties of plants. In this paper, we analyzed the status quo and significance of the application of filming technique in the PVP （Plant Variety Protection） system, and provided an introduction about the application of filming technique in DUS test in China.

TRANSPARENT AND CONDUCTIVE OXIDE FILM GROWTH AND APPLICATION

Thin layer polycrystal oxides (amorphous and micro-crystalline) TiO2(Fe2O3, SnO2 and ln2O3 · Sn) are prepared by the organometallic chemical vapor deposition (MO-CVD) technique at 300-410℃ . Their structures, surface states and photoelectrochemical properties are described by X-ray diffraction (XRD), electron microscopy and three electrode methods. The experiments indicate that these thin layer oxides are suitable for formly transparent conductive coating to serve as photoelectrodes and photocatalysts for splitting of water.

Grace at Arm＇s Length： The Cultural Importance of Utilizing ＂Expositive Puzzle＂ in Independent Film

Many independent films provide a realistic interpretation of everyday events. Passive viewing techniques used by independent scriptwriters and filmmakers require active engagement from the viewer in order to interpret characters and/or events. The following proposes that the ＂expositive puzzle＂ is an example of these techniques. It uses the fim Short Term 12 in order to demonstrate how the ＂expositive puzzle＂ works and to encourage use in real-world interactions in order to avoid interaction based on stereotypes.

NFT水肥一体化栽培系统的设计及能耗分析

NFT(Nutrient film technique)水肥一体化栽培系统采用PLC作为控制器、触摸屏作为人机交互界面,该系统能够使营养液按照设定的EC、pH和灌溉周期自动实现分区轮流灌溉,并具有远程监控功能。经实际运用证明,该NFT水肥系统运行稳定、操作方便,实现了NFT营养液的循环、间歇灌溉,配肥精度高,EC控制精度为±0.3 mS/cm。经试验,运用NFT水肥一体化系统栽培的上海青直接成本为0.195元/株,每株平均产量为0.118 kg。该系统满足温室NFT栽培灌溉的需求,具有一定的应用和推广价值。

非线性光学晶体K_(3.0)Li_(2.0)Nb_(5.0)O_(15.0)的生长

Potassium lithium niobate single crystal with a dimension of 20mm×15mm×30mm was grown by EFG technique in our laboratory.Compared with Czochralski method for the growth of KLN crystals,EFG technique possesses the following merits.Crack of crystals can be weakened during the lowering of temperature and the crystals free of crack can be obtained.The crystals have no rotation,the growth striation caused by the rotation of the crystals can be eliminated.With action of capillary from a die hole,the convective effect of melt at solid liquid interface can be reduced,therefore the homogeneity of crystals is better than that of crystals obtained by Czochralski method.The growth striation parallels each other and is perpendicular to the growth direction,so the good blue SHG can be obtained when ground wave goes through the KLN crystals.Since capillary force does not fully counteract the convective effect,the inhomogeneity of crystals can’t completely be eliminated.The low SHG conversion efficiency of KLN crystals is mainly caused by inhomogeneneity of crystals.For the growth of incongruent melting crystals,the growth rate is limited by the rejection of impurity,this also makes homogeneity of composition become bad.In the growth of KLN crystals by EFG technique,the fluctuation of the temperature at solid liquid interface should be enough small,and the film thickness of melt should be proper.Too thick film of melt makes the process of crystal growth unstable;too thin film of melt can lead to the constitutional supercooling.

Structural, optical and electrical properties of zinc oxide thin films deposited by a spray pyrolysis technique

Zinc oxide（ZnO） thin films were deposited on glass substrates by spray pyrolysis technique decomposition of zinc acetate dihydrate in an ethanol solution with 30 m L of deposition rate, the ZnO thin films were deposited at two different temperatures： 300 and 350℃. The substrates were heated using the solar cells method.The substrate was R217102 glass, whose size was 30×17.5×1 mm^3. The films exhibit a hexagonal wurtzite structure with a strong（002） preferred orientation. The higher value of crystallite size is attained for sprayed films at 350℃, which is probably due to an improvement of the crystallinity of the films at this point. The average transmittance of obtain films is about 90%–95%, as measured by a UV–vis analyzer. The band gap energy varies from 3.265 to 3.294 e V for the deposited Zn O thin film at 300 and 350℃, respectively. The electrical resistivity measured of our films are in the order 0.36 Ω·cm.

Reply to Comments on "Structural,Optical,and Electrical Properties of Zn-Doped CdO Thin Films Fabricated by a Simplified Spray Pyrolysis Technique'' by K.Usharani and A.R.Balu published in Acta Metall.Sin.(Engl.Lett.) 28(1),64–71(2015)

Following are the comments for the queries raised by Prof. Pawel E. Tomaszewski on our published paper entitled ＂Structural, Optical, and Electrical Properties of Zn-Doped CdO Thin Films Fabricated by a Simplified Spray Pyrolysis Technique＂ by K. Usharani and A.R. Balu published in Acta Metall. Sin.

Comments on "Structural,Optical,and Electrical Properties of Zn-Doped CdO Thin Films Fabricated by a Simplified Spray Pyrolysis Technique'' by K.Usharani and A.R.Balu Published in Acta Metall.Sin.(Engl.Lett.) 28(1),64–71(2015)

The commented paper [1] presents the results on structural, optical, and electrical properties of Zn-doped CdO thin films. Unfortunately, there are several mistakes and errors not found by any of referees. It is necessary to show these mistakes or misleading statements to avoid their use in the future papers by authors and other peoples.

Improvement of thickness uniformity and elements distribution homogeneity for multicomponent films prepared by coaxial scanning pulsed laser deposition technique

In conventional pulsed laser deposition （PLD） technique, plume deflection and composition distribution change with the laser incident direction and pulse energy, then causing uneven film thickness and composition distribution for a multicomponent film and eventually leading to low device quality and low rate of final products. We present a novel method based on PLD for depositing large CIGS films with uni- form thickness and stoichiometry. By oscillating a mirror placed coaxially with the incident laser beam, the laser＇s focus is scanned across the rotating target surface. This arrangement maintains a constant re- flectance and optical distance, ensuring that a consistent energy density is delivered to the target surface by each laser pulse. Scanning the laser spot across the target suppresses the formation of micro-columns, and thus the plume deflection effect that reduces film uniformity in conventional PLD technique is eliminated. This coaxial scanning PLD method is used to deposit a CIGS film, 500 nm thick, with thickness uniformity exceeding ±3% within a 5 cm diameter, and exhibiting a highly homogeneous elemental distribution.

Investigation of potential interferences on the measurement of dissolved reactive phosphate using zirconium oxide-based DGT technique

A diffusive gradients in thin films （DGT） technique based on hydrous zirconium oxide （Zr-oxide） has been recently developed for the measurement of dissolved reactive phosphate （DRP）. In this study, the detailed performance of the DGT technique is reported. Spiking experiments revealed that several orthophosphate monoester compounds contributed to the Zr-oxide DGT measurements of DRP. However, such a phenomenon is unlikely to occur during field conditions due to the low concentration of organic P in typical natural waters. The presence of Cl- （up to 106 g/L）, SO42- （up to 16 g/L）, HCO3- （up to 817 g/L）, and AsO2- and AsO 3 4 （both up to 1 mg As/L） in solutions had negligible effects on the measurement of DRP. The threshold concentrations of Cl-, SO42- and HCO3- have been increased from previous reports for the measurements of DRP using other adsorbent-based DGT techniques. The capacity for DGT measurements of DRP decreased with increasing solution pH （4.2-9.2）. The lowest capacity （95 μg P/m2 at pH 9.2） was still greater than that of other DGT techniques that are usually used for the measurement of DRP （2-12 μg P/cm2 ）. The Zr-oxide binding gel could be stored for up to 2 years without any aging effect. This period of validity was considerably longer than the ferrihydrite binding gel that is commonly used in present DGT devices （6 months）. The field application revealed that the concentrations of DRP measured in three fresh water samples using the Zr-oxide DGT technique were in agreement with those of the traditional colorimetric method.

Thermoluminescence study of rare earth ion (Dy^(3+)) doped LiF:Mg crystals grown by EFG technique

This work describes investigation of radiation dosimetry characteristics of magnesium （Mg） doped lithium fluoride （LiF） crystals co-doped with different concentrations of dysprosium （Dy）. These crystals were grown by edge defined film fed crystal growth （EFG） tech- nique. Thermoluminescence （TL） measurements were made on as grown （AG） and annealed （AN） crystals after they were irradiated with a gamma dose of 15 Gy. The influence and advantage of optimized Dy^3＋ concentration in enhancing the thermoluminescence （TL） properties of LiF：Mg samples were discussed. The normalized peak height of the annealed crystals was nearly 3 times that of the as grown crystals for the particular concentration samples irradiated with Co6~ gamma source showed linearity up to 10 Gy. Thermoluminescence signal observed over a period of one month showed negligible fading. Thermoluminescence glow curve structure of optimized phosphor remained stable for higher doses of gamma rays of 103 Gy. Glow curve was analyzed using computer glow curve deconvolution （CGCD） method and trapping parame- ters were calculated.

Preparation of n-type semiconductor SnO_2 thin films

We studied fluorine-doped tin oxide on a glass substrate at 350℃using an ultrasonic spray technique. Tin（Ⅱ） chloride dehydrate,ammonium fluoride dehydrate,ethanol and NaOH were used as the starting material, dopant source,solvent and stabilizer,respectively.The SnO_2：F thin films were deposited at 350℃and a pending time of 60 and 90 s.The as-grown films exhibit a hexagonal wurtzite structure and have（101） orientation.The G = 31.82 nm value of the grain size is attained from SnO_2：F film grown at 90 s,and the transmittance is greater than 80%in the visible region.The optical gap energy is found to measure 4.05 eV for the film prepared at 90 s, and the increase in the electrical conductivity of the film with the temperature of the sample is up to a maximum value of 265.58（Ω·cm）^（-1）,with the maximum activation energy value of the films being found to measure 22.85 meV,indicating that the films exhibit an n-type semiconducting nature.

Innovative design for a portable hybrid system of hydroponic and microalgae to produce food and biofuels

This study investigates an innovative hybrid system that combines hydroponics and microalgae in a compact portable shipping container.This container is divided into two parts;one contains the microalgae system and the other contains the hydroponic system.This combined system works by dividing the 24 hours into 12 hours of light and 12 hours of dark for each part.Both parts are connected using light-impermeable pipes that pass carbon dioxide from the dark side to the lit side and oxygen from the lit side to the dark side.In this paper,the authors developed a validated mathematical model for hydroponic and microalgae to evaluate the system’s performance.Results found by the model show the optimum parameters for the split photobioreactor and hydroponic system.The first investigated parameter is the sparger diameter for split the photobioreactor and the second is the number of plants that give the better and optimum result.The optimum modelling design for the combined hydroponic and microalgae system was using 100 plants for lettuce and three photobioreactors with a 0.009-m diameter for sparger to a photobioreactor system with an area of 15.6 m^(2).