太阳辐射换热空调制冷技术探讨

夏季太阳能辐射强度与空调制冷负荷有很好的一致性,这使得太阳能辅助空调具有特定的优点将太阳辐射转变为热能,通过热能实现制冷的方式最具有应用前景,也是一种实用的低碳环保节能技术,具有一定的推广应用价值。     

连续混炼过程比能耗分析

将连续混炼过程的有效比能耗分为升温、混炼、脱挥和建压比能耗,并提出了计算各项的一种方法。用该方法对不同机型、不同规格、不同加工对象的连续混炼机的比能耗进行了分析。结果表明,在多数连续混炼过程中,升温比能耗在总有效比能耗中所占比例都较大,建压比能耗所占比例都很小;原料热物性是影响有效比能耗及其构成的根本因素;当原料和混炼产物质量确定时,连续混炼机的螺杆与机筒结构、螺杆直径、产量、混炼工艺等都会影响有效比能耗及其构成。     

多弧离子镀与磁控溅射共沉积TiN/TiCN多层膜的高温抗氧化性能

TiN/TiCN多层膜的高温抗氧化性研究对于扩大其应用领域具有重要作用,但目前鲜见相关报道。采用多弧离子镀与磁控溅射技术以不同调制周期在304不锈钢表面共沉积TiN/TiCN多层膜。采用XRD、XPS、倒置显微镜及高温氧化试验研究了多层膜的高温抗氧化行为。结果表明:TiN/TiCN多层膜表面光滑平整、均匀致密,薄膜主要为具有Ti-(C,N)键的fcc-TiN结构;随着调制周期的减小,TiN/TiCN多层膜生长取向发生转变,且具有(111)晶面生长织构;随着氧化温度的升高,多层膜的显微硬度逐渐降低,氧化增重速率不断增大,且在700℃之后变化速率较快,薄膜的开始氧化温度约为750℃;随着调制周期的减小,多层膜TiN与TiCN界面层数量增多,促使晶粒细化,提高了其致密性,还隔断了缺陷贯穿薄膜的连续性,显著降低了薄膜的孔隙率,致使O原子扩散困难,增强了薄膜的高温抗氧化性能。     

MgO/La2O3CO3复合材料对磷酸盐的吸附特征

采用水热法制备了MgO/La2 O2 CO3复合材料(ML).采用X射线衍射仪和扫描电子显微镜对其结构及表面形貌进行了表征,利用Zeta电位仪测定了其零点电位点,并探究了接触时间、初始磷酸盐浓度和初始pH对磷酸盐吸附效果的影响.结果 表明,ML呈现板块状堆叠而成的层状结构,零点电位点为4.52.准二级动力学模型和Fre...     

Torsion sensor based on two cascaded long period fiber gratings fabricated by CO2 laser pulse irradiation and HF etching technique respectively

A novel torsion sensor is proposed, which is composed of one long period fibre grating and one asymmetrically corrugated long period fibre grating based on the high-frequency CO₂ laser pulses technology and burning fibre coating and etching cladding technology, respectively. By combing the advantages of the two aforementioned elements, a sensitivity of 331.7 and 310.3 pm/(rad/m) towards clockwise and anticlockwise direction, respectively, is reached in the experiments.     

Fabrication of Cu(In,Ga)Se2 thin films by ion beam sputtering deposition from a quaternary target at different substrate temperatures

Cu(In, Ga)Se₂ (CIGS) thin films were fabricated by ion beam sputtering deposition from a single quaternary target at different substrate temperatures (T _sub). The thin films were characterized with X-ray diffractometry, scanning electron microscopy, energy-dispersive X-ray spectroscopy and four-point probe technique to study the microstructures, surface morphology, composition and electrical properties, respectively. The results show that the films grown above 400?°C are of chalcopyrite structure. Cu(In_0.7Ga_0.3)Se₂ thin film was obtained when T _sub is 550?°C. The Cu and Se atomic percentage when T _sub is above 500?°C is higher than when T _sub is below 500?°C. With the increase in T _sub, the surfaces morphology of the films is denser and the resistivity of the films decreases.     

Self-assembly synthesis of cactuslike Cu2O 3D nanoarchitectures via a low-temperature solution approach

Cu₂O nanocactuses were synthesized via a simple, low-temperature, and no time-consuming wet chemical route. The synthesized products were systematically studied by X-ray powder diffraction, scanning electron microscopy, and transmission electron microscopy. The results showed that the formation of Cu₂O nanocactuses was strongly depended on the addition of CTAB and NaOH. The structural evolution of the cactuslike Cu₂O was found to follow dissolution and recrystallization processes. It is noteworthy that the stepwise synthetic procedure was crucial to the growth of the final nanoarchitectures. UV–vis spectrum was also used to estimate the absorption and photodegradation ability of the nanocactuses.     

Transport and Magnetic AC Losses in Ag/Tl-1223 Tape and the Effect of Mechanical Damage

In this paper we present the results of AC loss measurements on silver clad monocore tapes of Tl-1223 prepared by the powder-in-tube method. Losses arising from an external AC magnetic field are compared with those generated by AC transport currents (self-field losses). Critical current densities are derived from magnetic loss data and compared with those measured by the four point transport method. It was found that mechanically induced stresses (introduced by bending) only have a significant effect on the transport losses, via the critical current degradation. Such changes are not seen in measured magnetic losses, which are independent of mechanical stress, and remain unchanged, at least in the stress range used in our experiment.     

In-fiber liquid-level probe based on Michelson interferometer via dual-mode elliptical multilayer-core fiber

Abstract

An in-fiber liquid-level probe fabricated from homemade dual-mode elliptical multilayer-core fiber (EMCF) was proposed and experimentally demonstrated. The proposed sensor simply consists of a segment of the EMCF with one end coated with silver film, and a Michelson interferometer is roughly established when light from single-mode fiber incident from the other end. The detected interference patterns, rather clean due to the few-mode property, shift as the liquid level due to strong interaction between high-order modes and measurands through evanescent waves. Both the propagation characteristics and operation principle of such a sensor were demonstrated in detail, and sensitivities of 33.48, 43.35, and 48.93 pm/mm corresponding to liquid indices of 1.333, 1.353, and 1.373 were successfully achieved with a 50-mm EMCF probe, respectively. Moreover, the proposed sensor had the potential to discriminate measurand index after proper calibration.