Advances in estimation methods of vegetation water content based on optical remote sensing techniques

Quantitative estimation of vegetation water content(VWC) using optical remote sensing techniques is helpful in forest fire as-sessment,agricultural drought monitoring and crop yield estimation.This paper reviews the research advances of VWC retrieval using spectral reflectance,spectral water index and radiative transfer model(RTM) methods.It also evaluates the reli-ability of VWC estimation using spectral water index from the observation data and the RTM.Focusing on two main definitions of VWC—the fuel mois...     

论定制时装的发展趋势

随着经济实力增长、跨行业跨地区跨国界人际交往增多,我国一些高级人士在出席社交、宴会、庆典等重要场合时,需要能代表自身地位,文化修养与社会层次的服装.定制时装恰好能满足这部分人群的需求,同时也为我国服装市场的发展带来新的机遇和挑战.文章简述了定制时装在国内的市场现状,并从行业背景和设计角度分析了今后的发展趋势.     

2-[4-(9H-9-咔唑)-苯基]蒽醌的合成与表征

以苯酐和咔唑为原料,通过Friedel-Crafts酰基化、浓硫酸催化、Ullman、Suzuki偶联等反应,合成了标题化合物,并对该化合物进行紫外可见吸收和荧光分析。     

乡村关系研究的视野与路径——以甘肃省若干乡镇为例

村民自治语境下的乡村关系应该赋予新的时代内涵,如何处理好乡村关系是个理论问题,要具体分析政策法规的规定,还要调查多年来乡村关系形成的历史痕迹对乡村关系的影响。在调查研究的基础上,分析了不同类型的乡村关系,提出了新时期定位乡村关系必须处理好的几个问题,并在方法上予以指导。     

论新历史小说对欲望的重新叙述

阶级学说对个人尤其是个人欲望的压抑几近半个世纪之久,新时期以来的文学虽然将个人合理的欲望放在突出的位置并加以表现,但却仍然使用了话语转移叙述策略,本质上并没有摆脱政治乌托邦性质和理想主义色彩.新历史小说以其特有的对历史的欲望化言说方式和对人的本能欲望的肯定,真正实现了新时期以来文学对欲望的重新叙述,解构了传统的历史观念,让我们得以窥见人性的善恶.     

Process design for multi-stage stretch forming of aluminium alloy aircraft skin

A process design approach for multi-stage stretch forming was proposed by combining the strain distribution method and finite element method (FEM) to determine the minimum stage number and deformation amount of each stage. The strain distribution method was used to calculate the deformation amount of each stage and evaluate the formability through a safety criterion. FE simulation was taken as an analysis tool to reveal the deformation behaviour, to predict the strain contour and to determine the process parameters at each stage. To evaluate the effect of heat treatment after pre-strain on occurrence of deformation defects during the subsequent deformation, a multi-stage uniaxial tension test for 2B06 aluminium alloy sheet was carried out. A case study demonstrates that the approach has high reliability and good practicability.     

2,6-二氨基-3,5-二硝基吡啶-1-氧化物的精制及其性能研究

为了研究不同溶剂精制的2,6-二氨基-3,5-二硝基吡啶-1-氧化物(ANPyO)的性能,分别以三氟乙酸(CF3COOH)、二甲基亚砜(DMSO)和N,N-二甲基甲酰胺(DMF)为溶剂,采用重结晶法精制ANPyO,对精制后样品性能进行比较研究.结果表明:用CF3COOH重结晶精制的ANPyO,粒度主要分布在2～70 μm,比表面积为0.454 m2·g-1; 在升温速率为10 K·min-1的条件下,分解热焓为1021.46 J·g-1,最高峰值温度为370.69 ℃,表观活化能为279.63 kJ·mol-1;撞击和摩擦感度,分别为 20%和18%.     

河南油田双河水厂虹吸滤池改造及其效果评价

针对河南油田双河水厂虹吸滤池存在的处理水量下降、出水浊度偏高、自用水量上升等问题进行了深入探讨,采用微孔射流辅助冲洗工艺进行技术改造,改造后与改造前相比,出水浊度显著降低,反冲洗周期适当延长,滤料含泥量明显下降,自用水量下降,达到了预期目的。