酒中乙醇浓度国标检测方法的改进

国标GB 5009.225-2016《食品安全国家标准酒中乙醇浓度的测定》第二法为酒精计法,标准方法将制备好的试样注入100m L或200m L量筒中用分度值为0.1%vol的精密酒精计读取酒精度值,在实际实验中无法实现该操作。本文通过对该国标方法的改进,能准确、高效的完成酒精计法测定酒中乙醇浓度。     

GIS技术在城市防洪排涝中的应用分析

随着城镇化进程不断加快以及气候变暖带来的极端气候变化,部分城市接连遭受大型洪涝灾害。暴雨洪涝在引起媒体与公众普遍关注的同时,也给城市管理部门的防御和对策研究带来了新的难题。GIS技术在空间信息分析上的广泛应用为城市应对汛期洪涝灾害提供了新方法和新思路。     

工业二氧化碳废气用于农作物增产的绿色减排途径

随着经济增长,结构转型,以及履行负责任大国的国际义务越来越重等因素,中国现在面临着节约能源、保护环境和减少温室气体排放的多重压力。主要论述了二氧化碳应用农业生产方面,既能减少碳的排放量,又能提高农作物产量,从而实现生态、农业双赢的局面。     

Feature extraction for high-resolution imagery based on human visual perception

Feature extraction is highly important for classification of remote-sensing (RS) images. However, extraction of comprehensive spatial features from high-resolution imagery is still challenging, leading to many misclassifications in various applications. To address the problem, a shape-adaptive neighbourhood (SAN) technique is presented based on human visual perception. The SAN technique is an adaptive feature-extraction method that not only considers spectral feature information but also the spatial neighbourhood as well as the shape of features. The distinct advantage of this approach is that it can be adjusted to different feature sizes and shapes. Assessment experiments on a Système Pour l'Observation de la Terre 5 (SPOT-5) image were conducted to perform classification of land use/land cover. Results showed that improvement with SAN features is not significant for supervised classifiers due to the spectral confusion problem that resulted from similar spectral signatures between farmland and green areas, but a particularly significant improvement is observed for the unsupervised classifier. For the unsupervised classification, the SAN features noticeably improved the overall accuracy from 0.58 to 0.86, and the kappa coefficient from 0.45 to 0.80, indicating promise in the application of SAN features in the auto-interpretation of RS images.     

Enhanced Mechanical Properties by Cyclic Compression in TiNb/Zr-Based Metallic Glassy Composite

A significant enhancement of yield strength and large plasticity was obtained in TiNb/Zr₅₅Cu₃₀Al₁₀Ni₅ composite by cyclic compression at the yield point. This phenomenon resulted from the cooperation of the metallic crystalline alloy TiNb and metallic glassy matrix Zr₅₅Cu₃₀Al₁₀Ni₅ in the composite. It was found that a large dislocation density of TiNb was produced during cyclic compression, which resulted in the increase of the strength. Meanwhile, the improvement of plasticity of the composite benefited from the propagation of excess shear bands in the glassy matrix, which were produced during the cyclic compression process. Hence, the collective effect of both resulted in the improved yield strength and large plasticity of the composite.     

Propagation characteristics of the ten-parameter family of partially coherent general anisotropic gaussian schellmodel (AGSM) beams passing through first-order optical system

Abstract

Based on the closed property of AGSM beams under the action of first-order optical systems, the explicit transformation and twist expressions for the principal axes of intensity distribution, transverse coherence distribution and the principal curvatures of phase front in the cross-spectral density function of AGSM beams are derived. For typical applications, for AGSM beams passing through free space, the twist and variation regularities of the principal axes and the principal curvatures are analysed in detail. The twist-free conditions are discussed and the twist influenced by the physical parameters of the incident beam analysed. It is shown from the analysis that the principal curvatures of phase front are not zero at the reference planes where any of the corresponding principal axes of the beam spot obtains its minimum, and the conditions where the principal curvatures are zero is discussed.     

Material phase transformation at high heating rate during grinding

The modeling of maraging steel phase transformation in grinding process is presented in this article. Specifically, heating rate and contact zone temperature are examined to quantitatively link material properties, wheel topography characteristics and process parameters to the kinetics of diffusion-controlled transformation and diffusionless transformation. Physics-based modeling and prediction for the volume fractions of phase transformation in continuous heating under anisothermal conditions are developed based upon the addition of volume fractions in sequential segmented isothermal processes of grinding. The predictive model is validated by 18Ni (250) maraging steel grinding experiments, X-ray diffraction measurements and regression analyses. Results are compared to the model predicted of martensite and ferrite phase volume fractions after grinding. The physics-based model is experimentally validated as viable to predict the occurrence and extent of phase transformation related to material properties, wheel topography and grinding thermal-mechanical loading. Finally, correlation analysis is used to quantify the importance of the input variables to both model-predicted and X-ray diffraction measured phase transformation results.     

乳化液及空气吹扫装置在冷轧单机架中的应用

介绍了吹扫系统中两个关键工艺参数,分析了乳化液喷射梁、防缠导板的结构特点和功能,最后介绍了乳化液及空气吹扫装置在单机架六辊冷轧中的具体应用。     

A Multi-Radio Multi-Channel Assignment Algorithm Based on Topology Control and Link Interference Weight for a Power Distribution Wireless Mesh Network

Wireless Personal Communications - In this paper, a multi-radio multi-channel (MRMC) assignment algorithm based on topology control and link interference weight for power distribution wireless mesh...     

实现智能管道与智能运营的协同——流量经营解决方案探讨

首先分析了流量经营的13个典型业务场景,提出了流量经营的建设方案,包括流量经营的措施和整体体系架构。然后提出了以GGSN为中心面向网络的智能管道和综合网关面向业务智能运营的远期建设思路。最后,提出了GGSN智能分流和综合网关深度业务处理的近期建设方案和双策略控制接口。