某型榴弹炮海上运输及存放中炮膛的防护处理

对4种炮膛防护工艺进行了中性盐雾试验以及大气暴露试验，通过试验对比得到了优选品种，说明了推荐原因。     

从土壤水动力学到生态水文学的发展与展望

在20世纪80年代,土壤水动力学成为我国水文水资源领域的一个新兴研究方向。在此后的30多年中,土壤水动力学得到了巨大发展,并对我国农田水利、水文水资源等领域的科学与技术起到了巨大的推动作用。以土壤水动力学为基础,逐步认识了非饱和土壤中水分与热量、溶质等耦合运移机理与规律,在20世纪90年代发展了土壤-作物-大气之间的水热交换和传输理论(即土壤-植物-大气连续体理论,简称SPAC理论)。以SPAC理论为基础,农田作物模型得到了快速发展,成为本世纪研究气候变化对农业水资源和粮食生产影响的主要工具。与此同时,从农田到区域的水转化机理与规律、不同尺度的农业用水效率、以及水资源开发利用的生态和环境影响等基础科学问题和生产实践问题逐渐被重视,从而形成了新的交叉学科——生态水文学。生态水文学以水分-能量-物质耦合循环的动力学过程为基础,注重区域气候-植被/作物-水文相互作用的基础科学问题,旨在为区域水资源、生态和环境评价与管理提供科学依据。     

Preparation and characterization of SiC fibers with diverse electrical resistivity through pyrolysis under reactive atmospheres

Due to their fantastic mechanical and high-temperature resistant properties, SiC fibers with electrical resistivity of different orders of magnitude are of great interest for the fabrication of advanced composites with electromagnetic wave absorbent performance as both structural and functional materials. On the basis of well-developed route to prepare SiC fibers, in this work, we demonstrated a facile strategy to fabricate SiC fibers with electrical resistivity of 10⁻¹–10⁶ Ω cm by simply employing hydrogen and ammonia as the reactive atmospheres. The SiC fibers with different electrical resistivity had favorable morphologies, with uniform elemental distribution and stable C/Si ratio towards the fiber interior. Moreover, these fibers exhibited excellent mechanical strength and high temperature performance. Due to the innovative strategy, convenient operation and scalable preparation, the method in this work can be further extended to prepare SiC base fibers with adjustable electrical resistivity from other precursors.     

Approaches adopted to assess environmental impacts of PCDD/F emissions from a municipal solid waste incinerator

Different approaches were carried out in this work to assess environmental impacts of a municipal solid waste incinerator. A total of seven sites in the vicinity of the facility were chosen to collect air, banyan leaf and soil samples for analyses of PCDD/Fs by high-resolution gas chromatography/high-resolution mass spectrometry. Based on the PCDD/F concentrations of the three matrices determined at sites upwind, downwind and area of maximum ground concentration, it was found that the environmental impact of the MSWI was not obvious. PCDD/F concentration isopleths of the three environmental compartments coupled with wind rose of the region proved that the influence of the MSWI on the environment was also rather limited. It clarified emission sources by confirming that the PCDD/F concentrations originated mostly from the existing stationary emission sources in the vicinity. Through principal component and cluster analyses on congener profiles, the influence of metallurgical facilities and medical waste incinerators on the ambient air was assessed. Moreover, the modeling of ISCST3 demonstrated also that the contribution of the MSWI to ambient atmospheric PCDD/Fs was minimal. The approaches studied have led to identical conclusions, and thus are useful to cross-evaluate the environmental impact of an MSWI.     

On the aerosols monitoring by satellite observations

Particulate matter is the general term used to identify a complex mixture of organic and inorganic particles (aerosols) that can be found suspended in the atmosphere in solid, liquid or both physical states. The presence of particulate of non-natural origin is linked to important climatic and environmental effects. The interactions of these particles with the solar radiation, the Earth and the atmospheric gases, can modify the atmosphere physical and chemical characteristics, the temperature vertical profile and other thermodynamic variables, as well as the Earth surface characteristics and its temperature. Studies on the particles have furthermore demonstrated the existence of a link between the presence of fine and ultra-fine particulate of non-natural origin and some effects on the health of human and other living being. The aerosols can contaminate a wide area of the region surrounding the source of particulate. Based upon all these reasons it is considered the utmost importance to develop a satellite-based system capable of monitoring the presence of particulate on very large areas. This paper provides methodologies to identify atmospheric particles by means of satellite-based sensors operating both in the reflective and in the thermal infrared part of the electromagnetic spectrum.     

地形对高山区TM积雪定量遥感的影响

高山区积雪的辐射特性受到高度迅速变化和地形强烈分异的显著影响,必须对图像进行辐射纠正和地形纠正以得到标准化的图像。利用大气纠正模型和对太阳辐照入射度的模拟,在高精度数字高程模型和实验区气象观测资料的支持下,通过计算光谱反射比而实现地形标准化,是一条行之有效的方法。这一方法在天山乌鲁木齐河上游冰川区得到了实际检验,被证明是实现积雪定量遥感,提高积雪区地物分类精度的重要前提。并对这一方法的局限性进行了讨论。     

燃烧源排尘粒度分级的测试

通过对大量的炉窖排尘的测试,给出了不同炉型烟尘粒度分级,从中看出排尘中飘尘和微粒占有较大的比重,对环境和人群危害是较大的,应引起人们足够的重视。     

气调保鲜包装机气体比例混合器的研究

综述了气调保鲜包装机中气体比例混合器的原理、类型及气体混合配送技术,研究了应用气体比例混合器的新技术实现不同比例气体的调节与组合,连续不断地供给气调保鲜包装机,适应各种被包装物品的保鲜包装要求。     

Effects of TIG surface treating on microstructural characteristics and mechanical properties of Al2O3–TiB2 coating by APS

Abstract

The pulsed DC tungsten inert gas (TIG) method was employed to post-spray treat an electroconductive Al₂O₃–TiB₂ coating by atmosphere plasma spraying (APS) Al₂O₃–30 wt-%TiB₂ powder. The microstructure and mechanical properties of the coatings before and after treatment were comparatively investigated by scanning electron microscopy, laser scanning confocal microscopy, X-ray diffraction, microhardness tester and block on ring wear tester. It was detected that the treated coating presented a two layer structure consisting of the remelted zone and the sintered zone, which was comprised of TiB₂ and single α-Al₂O₃; surface roughness of the treated coating exhibited a remarkable decrease while microhardness and wear resistance showed a significant increase. These experimental results could be ascribed to the effect of high heat input and discharge plasma during the pulsed DC TIG treating.     

SANAA建筑氛围的营造 — —以新现象学的视角解读

氛围是介于主客体之间的空间 感受,人们首先通过氛围来体验建筑。以 SANAA建筑中的氛围为研究对象,依据赫 尔曼·施密茨新现象学中的氛围研究,借助其 中的情景共建、联觉特性,以及运动暗示理 论,分别从建筑特征、行为体验、设计意识 三个层面,解读SANAA营造氛围的思想,剖 析其建筑中氛围的营造取决于活动场景、建 造方式,以及空间节奏。探索新现象学在建 筑设计中的实践方法,进而帮助鲜活的氛围 回归到建筑中。