LDV measurements of particle velocity distribution in an annular stripper

Particle descent velocities in an annular stripper were measured by a laser Doppler velocimetry (LDV) system. In the radial direction, particle descent velocity was relatively constant in the mid-region of the stripper and increased towards the walls on both sides, exhibiting an anti-U-shaped distribution. Particle descent velocity in the radial mid-region increased with the increase of superficial gas velocity, and the maximum in the outer wall region increased significantly with the increase of solid mass flux. Superficial stripping gas velocity had stronger effect on particle velocity distributions near the stripper gas distributor, and such effect weakened with the increase of the distance from the distributor. Local particle velocity and its radial profiles could be adjusted by changing the superficial stripping gas velocity. Empirical formulas were established to describe the relationships between the local particle velocity and cross-sectional averaged velocity based on the effects of operating conditions and measuring positions. The result showed that the predicted data was in good agreement with the experimental value.     

EFFECT OF Na,K AND Ce ON CRACK PROPAGATION RESISTANCE FOR ALLOY 8090

The crack propagation resistance for alloy 8090 sheet decreases with the increase of content ofNa and K impurities.An improvement over the fracture toughness and crack initiation resist-ance for the alloy containing Na and K within certain limit may be made by adding 0.05%Ce.This beneficial modification would not be manifested if the alloy contained more Na andK.One of the reasons why Na and K injure the toughness of the alloy might be due to thatthey cause the precipitation of T_1 phase along grain and subgrain boundaries and acceleratethe abnormal growth of recystallized grains.     

MECHANICAL PROPERTIES AND MICROSTRUCTURES OF Al-Mg-Li-Zr ALLOYS-CONTAINING SILVER

ＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＩＥＳＡＮＤＭＩＣＲＯＳＴＲＵＣＴＵＲＥＳＯＦＡｌ－Ｍｇ－Ｌｉ－ＺｒＡＬＬＯＹＳ－ＣＯＮＴＡＩＮＩＮＧＳＩＬＶＥＲ￥Ｚｈａｎｇ，Ｓｉｑｉ；Ｙｉｎ，Ｚｈｉｍｉｎ；Ｓｈｅｎ，Ｊｉａｎ；Ｌｕ，Ｂｉｎ；Ｌｉａｎｇ，Ｙｉｎｇ（...     

最优化技术在陶瓷配方优化设计中的应用

在陶瓷配方设计领域引入先进的计算机技术,应用优化陶瓷配方的主要方法一单纯形法,根据配方优化设计的需要,以绝对误差为目标函数,提出了基于多目标优化的配方最优化设计数学模型,使陶瓷配方设计问题转变为以原料上下限等为约束条件的极值问题。通过实例验证,这种模型能产生精度较高的最优解。     

Performance Comparison of Long-Wave Infrared Imaging Spectrometer Between Dyson Form and Offner Form

In view of the difficulties in traditional long-wave infrared imaging spectrometer which is hard to realize a high signal-to-noise ratio and miniaturization as well under the weak remote sensing signal,Offner convex grating spectrometer and Dyson concave grating spectrometer,both having concentric structure,are designed and analyzed in the band of 8-12 μm. The diffraction angle expressions of the two spectrometers are obtained and the diffraction characteristics are acquired. Both of the spectrometers are designed in Zemax environment under different F-numbers and different grating constants with the same slit,spatial resolution,spectral resolution and detector. The results show that Dyson grating spectrometer possesses the advantages of higher throughput and smaller volume, and Offner grating spectrometer possesses the advantage of more accessible material and the absence of chromatic aberration. The differences between Dyson form and Offner form show that the former is a better choice in the long-wave infrared imaging spectrometer.     

3D Prussian blue/Pt decorated carbon nanofibers based screen-printed microchips for the ultrasensitive hydroquinone biosensing

Nowadays,water pollution has become more serious,greatly affecting human life and healthy.Electrochemical biosensor,a novel and rapid detection technique,plays an important role in the real-time and trace detection of water pollutants.However,the stability and sensitivity of electrochemical biosensors remain a great challenge for practical detections in real samples to the strong interferences derived from complex components and coagulation effects.In this work,we reported a novel three-dimensional architecture of Prussian blue nanoparticles (PBNPs)/ Pt nanoparticles (PtNPs) composite film,using 3D interweaved carbon nanofibers as a supporting matrix,for the construction of screen-printed microchips-based biosensor.PtNPs with diameters of～2.5 nm was highly dispersed on the carbon nanofibers (CNFs) to build a 3D skeleton nanostructure through a solvothermal reduction.Subsequently,uniform PBNPs were in-situ self-assembled on this skeleton to construct a 3D architecture of PB/Pt-CNF composite film.Due to the synergistic effects derived from this special feature,the as-prepared hydro-quinone (HQ) biosensor chips can synchronously promote both surface area and conductivity to greatly enhance the electrocatalysis from enzymatic reaction.This biosensor has exhibited a high sensitivity of 220.28 μA·L·mmol-1·cm-2 with an ultrawide linear range from 2.5μmol·L-1 to 1.45 mmol·L-1 at a low potential of 0.15 V,as well as the satisfactory reproducibility and usage stability.Besides,its accuracy was also verified in the assays of real water samples.It is highly expected that the 3D PB/Pt-CNF based screen-printed microchips will have wide applications in dynamic monitoring and early warning of ana-lytes in the various practical fields.     

Nickel-Carnosine complex:A new carrier for enzymes immobilization by affinity adsorption

Immobilization is an effective method to promote the application of enzyme industry for improving the stability and realizing recovery of enzyme.To some extent,the performance of immobilized enzyme depends on the choice of carrier material.Therefore,the development of new carrier materials has been one of the key issues concerned by enzyme immobilization researchers.In this work,a novel organic-inorganic hybrid material,nickel-carnosine complex (NiCar),was synthesized for the first time by solvothermal method.The obtained NiCar exhibits spherical morphology,hierarchical porosity and abun-dant unsaturated coordination nickel ions,which provide excellent anchoring sites for the immobiliza-tion of proteins.His-tagged organophosphate-degrading enzyme (OpdA) and ω-transaminase (ω-TA)were used as model enzymes to evaluate the performance of NiCar as a carrier.By a simple adsorption process,the enzyme molecules can be fixed on the particles of NiCar,and the stability and reusability are significantly improved.The analysis of protein adsorption on NiCar verified that the affinity adsorp-tion between the imidazole functional group on the protein and the unsaturated coordination nickel ions on NiCar was the main force in the immobilization process,which provided an idea way for the develop-ment of new enzyme immobilization carriers.     

无核紫葡萄太阳能干燥技术的研究

采用一种空气集热器-温室型太阳能干燥装置,在新疆石河子市的气候条件下验证了无核紫葡萄太阳能干燥的可行性,从2007年8月到10月间,进行了一系列的试验.试验表明:与自然晾晒相比,太阳能干燥周期缩短为原来1/3的时间,干燥质量也有大幅度的提高.     

Modelling and computation of unsteady turbulent cavitation flows

1. INTRODUCTION Cavitatating flows are important phenomena happened in industry setups and many under-water vehicles. It leads to performance losses and modifications of blade load when happened in machines, especially turbo-machinery. Nevertheless, cavit…     

特构斯河山口引水枢纽的引水防沙设计及试验研究

通过特克斯河口引水枢纽的试验研究，解决了常遇洪水低水位运行时河流两岸的引水问题，优化了水平县板特结构形式，收到了较好的引水防沙效果，为县板分层式引水枢纽工程设计提供了新经验。