Preparation and Compressive Stress Effect of Polymer Matrix RE-Fe Giant Magnetostrictive Composite

Polymer matrix RE-Fe giant magnetostrictire composite （GMPC） was prepared using bonding and magnetic field forming technique, and magnetostriction of samples was measured for different compressive stress. The experimental results show thai there is certain compressive effect in GMPC. And the influence of compressive stress on magnetostriction of sample was investigated. It offers essential reference for application and device design of GMPC.     

Current Conditions and Outlook of Global Offshore Oil and Gas Exploration

The world is rich in offshore oil and gas resources. The offshore oil reserves account for about 34 percent of the world＇s total. With a 30 percent proven rate, offshore oil exploration is still in its preliminary stage. Based on the statistics by ＂Oil ＆ Gas Journal,＂ as of the January 1, 2006, the proven oil reserves worldwide are 175.7 billion tons and the proven natural gas reserves 173 trillion cubic meters. The global offshore oil reserves approach 135 billion tons, of which 38 billion tons are proven, while the offshore natural gas reserves amount to about 140 trillion cubic meters, of which 40 trillion cubic meters are proven.     

Effect of RE on Granulation of Eutectic Carbide in Ledeburite Steel

ＲｅｃｅｎｔｌｙｔｈｅｂｅｎｅｆｉｃｉａｌａｃｔｉｏｎｓｏｆＲＥｏｎｉｒｏｎａｎｄｓｔｅｅｌｓｈａｖｅｂｅｅｎｒｅｐｏｒｔｅｄａｒｏｕｎｄｔｈｅｗｏｒｌｄ．ＲＥｃａｎｎｏｔｏｎｌｙｄｅｏｘｉｄｉｚｅａｎｄｄｅｓｕｌｐｈｕｒｉｚｅｔｈｅｍｅｌｔａｎｄｆ...     

Multi-Scale Dilated Convolutional Neural Network for Hyperspectral Image Classification

基于多尺度空洞卷积神经网络的高光谱图像分类

郑姗姗¹,刘文¹,单锐¹,赵静一²,江国乾³,张智⁴

（1. 燕山大学理学院,河北 秦皇岛 066004;2. 燕山大学机械工程学院,河北 秦皇岛 066004;3. 燕山大学电气工程学院,河北 秦皇岛 066004;4. 北京航天研究所,北京 100094）

创新点说明：

1）将图像分割方法——空洞卷积用于卷积神经网络进行高光谱图像分类,提取更加广泛、抽象的图像特征。

2）构建基于多尺度空洞卷积神经网络的高光谱图像分类方法。搭建多尺度聚合结构,在每个通道中使用快捷连接和空洞卷积结构,有效提取图像特征,避免信息丢失。

研究目的：

针对图像信息丢失问题,得到高精度的高光谱图像分类方法。

研究方法：

在Indian Pines和Pavia University数据集上,与4个已有的高光谱图像分类方法进行对比实验,比较OA, AA和Kappa值。

研究结果：

多尺度空洞卷积神经网络在Indian Pines和Pavia University数据集上OA值分别达到了99.58%,99.92%。AA值分别达到了99.57%,99.90%。Kappa分别达到了99.52%,99.89%。

结论：

1）在卷积神经网络中引入空洞卷积,可以有效避免图像信息丢失。

2）多尺度空洞卷积神经网络能提取更佳的判别性特征,实现高分类性能。

关键词：多尺度聚合;空洞卷积;高光谱图像分类;快捷连接

     

AN EXPERIMENTAL-NUMERICAL METHOD FOR MEASURING CRACK PROPAGATING VELOCITIES UNDER STRESS WAVE LOADING

An experimental-numerical method for measuring dynamic crack propagating velocities under stress wave loading is established in this paper. The experiments of the three-point bend specimen are done on the improved Hopkinson bar. Deflection of loading point, dynamic load and instantaneous crack length are measured, then crack propagating velocities are calculated. Experiments on 40Cr steel show that the results given by this method have a good agreement with that obtained by the resistance fracture gage method. Therefore this method is feasible for measuring crack propagating velocities under high loading rate and will have wide application.     

Efficient MgO-doped CaO sorbent pellets for high temperature CO2 capture

Novel MgO-doped CaO sorbent pellets were prepared by gel-casting and wet impregnation. The effect of Na⁺ and MgO on the structure and CO₂ adsorption performance of CaO sorbent pellets was elucidated. MgO-doped CaO sorbent pellets with the diameter range of 0.5-1.5 mm exhibited an excellent capacity for CO₂ adsorption and adsorption rate due to the homogeneous dispersion of MgO in the sorbent pellets and its effects on the physical structure of sorbents. The results show that MgO can effectively inhibit the sintering of CaO and retain the adsorption capacity of sorbents during multiple adsorption-desorption cycles. The presence of mesopores and macropores resulted in appreciable change of volume from CaO (16.7 cm³∙mol⁻¹) to CaCO₃ (36.9 cm³∙mol⁻¹) over repeated operation cycles. Ca2Mg1 sorbent pellets exhibited favorable CO₂ capture capacity (9.49 mmol∙g⁻¹), average adsorption rate (0.32 mmol∙g⁻¹∙min⁻¹) and conversion rate of CaO (74.83%) after 30 cycles.     

Fabrication and performance evaluation of novel transparent ceramics RE:Tb3Ga5O12(RE=Pr,Tm,Dy)toward magneto-optical application

Transparent ceramics are at the heart of modern magneto-optical materials providing promising opportunities for Faraday isolators.1.0 at%RE:Tb3Ga5O12(rare earth(RE)=Pr,Tm,Dy)transparent ceramics were successfully prepared by air sintering and sequential HIP technique using the coprecipitated powders as the raw material.All the powders have shown to be a pure cubic terbium gallium garnet(TGG)phase and exhibit good dispersion.Additionally,a change could not be observed in particle shape with the different doped ions.After the two-step sintering,all the obtained ceramics have good optical quality,and the in-line transmittances at 1070 nm are higher than 80%.Moreover,no secondary phase can be detected from the microstructures.However,the pores which remain entrapped in the ceramics can be noted.The Verdet constant of ceramic samples is optimized by RE doping,and the Verdet constant at 632.8 nm is about?143 rad·T^?1·m^?1,which is about 5%higher than that of TGG ceramics.Finally,the thermo-optical properties of 1.0 at%RE:TGG transparent ceramics are compared.The annealed TGG ceramic showed the best thermo-optical properties,and the thermally induced depolarization of 1.0 at%Ce:TGG and 1.0 at%Tm:TGG was inferior to that of annealed TGG ceramic.     

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.     

FORMATION OF MANGANESE SILICIDE THIN FILMS BY SOLID PHASE REACTION

1. IntroductionThe transition metal silicides have attraeted much attention because of their potentialapplicatiOIl in very large scale integration (VLSI) de.ice[1]. Near-noble metal silicides canbe used as Schottky al1d ohn1ic col1tacts in silicon-based d…