基于图像处理的棉红枯病染病程度研究

为了有效地对棉红枯病的染病程度进行度量,首先运用综合阈值方法从背景图片中分割出叶面区域,根据棉红枯病的染病特点,在RGB颜色空间上提取叶面区域的红色和绿色分量;然后计算其平均值,将两个平均值相除得出红绿比。采用此方法分别对健壮叶面、染病叶面以及重染病叶面进行处理,得出各染病程度的红绿比取值范围并验证。研究表明,利用此方法进行染病程度的度量是可行的,为有目的地对棉花进行处理提供了理论依据。     

Food-based dietary guidelines and implementation: lessons from four countries--Chile, Germany, New Zealand and South Africa

OBJECTIVE: Food-based dietary guidelines (FBDGs) are globally promoted as an important part of national food and nutrition policies. They are presented within policy as key features of the strategy to educate the public and guide policy-makers and other stakeholders about a healthy diet. This paper examines the implementation of FBDGs in four countries: Chile, Germany, New Zealand and South Africa - diverse countries chosen to explore the realities of the FBDG within policy on public health nutrition. DESIGN: A literature review was carried out, followed by interviews with representatives from the governmental, academic and private sector in all four countries. RESULTS: In all four countries the FBDG is mainly implemented via written/electronic information provided to the public through the health and/or education sector. Data about the impact of FBDGs on policy and consumers' food choice or dietary habits are incomplete; nutrition surveys do not enable assessment of how effective FBDGs are as a factor in dietary or behavioural change. Despite limitations, FBDGs are seen as being valuable by key stakeholders. CONCLUSION: FBDGs are being implemented and there is experience which should be built upon. The policy focus needs to move beyond merely disseminating FBDGs. They should be part of a wider public health nutrition strategy involving multiple sectors and policy levels. Improvements in the implementation of FBDGs are crucial given the present epidemic of chronic, non-communicable diseases.     

Quantitative precursor studies on di- and trihydroxybenzene formation during coffee roasting using "in bean" model experiments and stable isotope dilution analysis

The objective of this study was to investigate the potential of various raw bean components as precursors of pyrogallol (1), hydroxyhydroquinone (2), catechol (3), 4-ethylcatechol (4), 4-methylcatechol (5), and 3-methylcatechol (6) under quasi "natural" roasting conditions by using the recently developed "in bean" model roast experiments. Freeze-dried, fully extracted bean shells were loaded with aqueous solutions of either single coffee compounds or fractions isolated from the raw bean solubles. After freeze-drying, these reconstituted beans were roasted, aqueous coffee brews were prepared, and the target phenols were quantified by means of a stable isotope dilution assay with LC-MS/MS detection. On the basis of the quantitative data, it can be concluded that upon coffee bean roasting, catechol (3) is primarily formed by degradation of caffeoylquinic acids from both the caffeic acid and the quinic acid moiety of the molecule, as well as from Maillard-type reactions from carbohydrates and amino acids. In contrast, pyrogallol (1) and hydroxyhydroquinone (2) are efficiently generated from carbohydrates and amino acids and, in addition, from free or chlorogenic acid bound quinic acid moieties. 4-Ethylcatechol (4) is exclusively generated upon thermal breakdown of caffeic acid moieties. 3-Methylcatechol (6) is formed primarily from the Maillard reactions and, to a minor extent, also from various phenolic precursors, whereas 4-methylcatechol (5) is produced in trace amounts only from all of the different precursors investigated. On the basis of this precursor study, reaction routes explaining the formation of the target phenols are proposed.     

地方文化资源数字化保护与文化创意品牌塑造

以惠州龙门农民画产业化为例,惠州龙门农民画是以“南蛮文化”作为独特视角,展现南国传统民俗风情的民间绘画,被誉为世界民间艺术奇葩。分析了产业化发展进程中龙门农民画的艺术特色和文化价值,阐述了基于知识管理的龙门农民画数字化保护思路,并从文化创意角度对龙门农民画的文化品牌塑造进行了探讨。     

深施型液态肥变量施肥控制系统

以深施型液态施肥机为依托,采用单片机作为核心处理器,以电磁比例调节阀为执行部件,设计了深施型液态变量施肥控制系统.设计了与硬件配套的上位机软件,用于采集数据与发送命令.喷肥针施肥量控制误差台架试验结果表明,该系统可实现深施型液态变量施肥,施肥误差不超过0.5 mL/次,满足液态变量施肥作业要求.     

微量元素对餐厨垃圾厌氧发酵的影响实验

针对餐厨垃圾厌氧发酵效率和稳定性较低的问题,采用CSTR反应器在中温（37±1）℃下探究了微量元素Fe、Co、Ni、Se、Mo、W对餐厨垃圾厌氧发酵的影响。结果表明当水力停留时间为40d,有机负荷为3g/(L·d)时,添加微量元素溶液的处理组和未添加微量元素溶液的对照组的平均甲烷日产量分别为7.1、6.7L/d,两者的甲烷体积分数分别为62.7%和61.6%;当有机负荷为4g/(L·d)时,对照组甲烷体积分数下降为19.5%,而处理组稳定在60%左右,且对照组的pH值由7.35下降为5.24,厌氧发酵失败,而处理组的pH值保持在7.2左右,厌氧发酵仍能稳定运行。实验结果表明,微量元素能够在一定程度上提高餐厨垃圾厌氧发酵的产甲烷效率和稳定性。     

Co含量对CoAPSO-5分子筛膜制备的影响

采用原位水热合成法在多孔α Al2O3上制备了连续致密的CoAPSO 5分子筛膜,并考察了Co含量对成膜过程的影响机制。通过XRD、SEM及ICP检测,证明所合成的为致密、均一、无取向CoAPSO 5分子筛膜,同时分析了合成液中进入分子筛的Co含量及其对CoAPSO 5分子筛膜的晶形、厚度及完备性的影响,并通过气体渗透法验证所合成的分子筛膜为无缺陷的。     

便携式农作物茎秆剪切力测试仪的设计与试验

为了能方便准确地测定农作物茎秆的剪切力学特性,设计了一种手动与电动两用便携式农作物茎秆剪切仪。该仪器以交流电动机或发条驱动装置作驱动机构,以STM32单片机为核心组成嵌入式控制平台,由拉/压力传感器采集压力信号,压力曲线等试验结果可以实时显示和SD卡存储,同时还能完成做功、最大压力等参数的计算。试验结果表明,该剪切力测试仪精度达到0.84%,工作稳定可靠。该仪器可满足作物茎秆剪切力检测的要求,为进一步研究农作物茎秆的力学性能提供了方便。     

日本包膜缓释肥料养分释放及微结构研究

采用恒温水培试验,研究了日本生产的五种包膜肥料(LP40、LPS40、SC60、LPSS和LPSS100)氮素释放特性,用一级反应动力学方程进行拟合,并用扫描电镜观察了包膜肥料水培前后膜的微观结构。结果表明,包膜肥料的膜材料不同,氮素释放量也不同;包膜肥料的氮素释放率随着时间的延长而增加;这五种包膜肥料的氮素释放特征均可用一级反应动力学方程来描述,氮素释放速率常数与氮素释放率成正比,与氮素溶出的半时值成反比;扫描电镜的图像分析结果显示,水培后LPSS、SC60的膜外表面完整性要好于LP40,LPSS的膜剖面结构很紧实,阻水性能好。