对基层农技推广队伍建设的思考

通过对全县基层农技推广队伍的调整,分析了基层农技推广队伍的现状并找出现有的问题,进而有针对性地提出解决问题的办法。     

草地环境电磁散射特性研究

研究了草地环境的电磁散射特性,以二维高斯粗糙面建立了草地环境分层结构。建立了鲜草和土壤的有效相对介电常数模型,绘出了鲜草、土壤有效相对介电常数随入射波频率的变化曲线,并总结了鲜草、土壤相对介电常数随入射波频率变化的规律。采用考虑了分层之间多次散射的微扰法(Small Perturbation Method, SPM)计算了鲜草含水量、土壤湿度、土壤层粗糙度及鲜草层粗糙度对草地环境后向电磁散射的影响。仿真结果表明,鲜草的含水量、土壤湿度、土壤层粗糙度及鲜草层粗糙度对草地的后向散射有不同程度规律性的影响。研究成果为草地粗糙度、地区的干旱程度以及是否有人畜活动痕迹的判断提供了理论参考。     

一种小型智能割草机器人的设计与实现

针对传统割草机污染高、噪音大和需要人工长时间操作等弊端,结合市场需求,研制了一款小型的可预约工作、自主回充的智能割草机器人。硬件上,系统以STM32为核心,由控制系统、动力系统、传感系统、通信系统和人机交互系统5部分组成;算法和软件上,采用自主回充方案,实现预约模式下机器人多次工作,减少人工操作;为解决机器人在斜坡上无法直线行进问题,设计了一种坡度补偿算法;同时为提高机器人的割草效率,提出了一种自主寻草算法。系统符合国际安全设计指标,经过长时间测试,机器在预约模式、自主回充模式均能稳定可靠的工作。     

香根草在铁路路基边坡防护中的机理和应用

铁路边坡防护直接影响列车运行安全,文章介绍了香根草国内外应用及其生物和工程特性,以及在铁路上的试验应用和具体实例,说明了香根草在铁路边坡防护上应大力推广和应用是符合可持续性发展要求的。     

荻CMP高浓磨浆的初步研究

经过化学处理的荻,在φ300mmKRK盘磨机中使用18034N齿盘进行高浓磨浆。浆的筛分析结果表明,一段磨浆主要作用是离解纤维,切断作用很小。在光显微镜下的观测证明,高浓(25％)磨浆时纤维的切断作用显著减少,而且润胀良好,保水值上升。这种经碱性H_2O_2温和处理的荻CMP浆在TEM电子显微镜下观测表明,在ML—P层间或在P—S_1层间未发生剥离现象,而是P和S_1层一起自纤维表面上部分脱落,二段磨浆比一段磨浆暴露出来的S_2层继续增多,提供了良好的纤维结合面积,有利于提高浆张的物理性能。在实验室试验条件下的初步研究证明,这种荻CMP应用在对白度要求不高的产品时,具有代替木浆使用或节约木材造纸潜力的可能性。     

Soil transformation of 2(3H)-benzoxazolone of rye into phytotoxic 2-amino-3H-phenoxazin-3-one

Nonsterile soil transforms the rye metabolite 2(3H)-benzoxazolone (BOA) into 2-amino-3H-phenoxazin-3-one, which is an order of magnitude more toxic to barnyard grass than benzoxazolone. Benzoxazolone was recovered unchanged from sterile soil. However,o-aminophenol is converted to aminophenoxazinone by both sterile and nonsterile soil in the presence of air. Aminophenoxazinone is probably produced by microbial hydrolysis of benzoxazolone intoo-aminophenol, which is oxidized to aminophenoxazinone in both sterile and nonsterile soil. No 2,2′-oxo-1,1′-azobenzene was found in any incubations of soil with benzoxazolone,o-aminophenol, oro-azophenol.     

Characterisation of traditional Albanian breads derived from different cereals

The long isolation of Albania and the scarcity of raw materials has traditionally led to the production of bread from crops other than wheat, like maize, which is the basic ingredient for maize bread (bukë misri), rye, which is used to prepare rye bread (bukë thekre), and chick-pea, used in chick-pea bread (bukë me qiqre). Today, these traditional breads are accompanied by other types, such as brown bread from soft wheat (bukë zize). In the present work, the traditional Albanian breads were characterised in order to assess their quality. The results obtained indicated that the protein content reflected the characteristics of the raw material used, being higher in the chick-pea bread and in bread made from high extraction rate wheat flour, while both fat and yellow pigment levels were higher in maize bread. A high humidity value was found in many of the breads examined, especially in maize bread, with consequent risks of moulds and a shortened shelf-life.     

Effects of various glucogenic sources on production and metabolic responses of dairy cows fed grass silage-based diets

Four rumen cannulated Finnish Ayrshire cows in midlactation were used in an experiment designed as a 4 x 5 incomplete Latin square with 2-wk periods to compare effects of glucogenic substrates on grass silage-based diets. The five treatments were continuous infusions of 1) water (control), 2) casein 300 g/d, 3) glucose 300 g/d, 4) propionic acid 247 g/d, and 5) barley starch 270 g/d. Substrates were infused either into the rumen (propionic acid) or into the abomasum (other substrates). As a basal diet, cows were fed a formic acid treated grass silage ad libitum (digestible organic matter 690 g/kg dry matter [DM], crude protein [CP] 131 g/kg DM) and a barley-rapeseed concentrate (CP 141g/kg DM) at a rate of 7 kg/d. Production responses to glucogenic substrates other than casein were negligible, suggesting that glucose supply of the cows did not primarily limit milk production. However, with casein cows produced significantly more milk, milk protein, and lactose than with other glucogenic substrates. Casein increased urea and essential amino acid (EAA), and decreased nonessential AA (NEAA) in arterial plasma compared with other substrates, suggesting that casein provided precursors both in terms of NEAA for gluconeogenesis and EAA for milk protein synthesis. This puts forward that providing the AA needs of the mammary gland for milk protein synthesis are met, glucose supply may become the next limiting factor for milk protein synthesis in cows fed diets based on restrictively fermented grass silage. The limited supply of AA from the basal diet, and possibly the low production levels of cows partly invalidated the hypothesis of monitoring differing glucogenic substrates for grass silage-based diets.     

杂交苏丹草镉的吸收与分布规律研究

随着土壤中添加镉量的增加,杂交苏丹草的株高明显降低,生物量显著下降。镉添加量为40mg kg土的处理,杂交苏丹草株高和地上部的生物量分别只有对照的48%和8.4%。不加镉的对照,杂交苏丹草根、茎、叶的含镉量分别为3.2,2.7,3.2μg g-1,各部位含镉量没有显著差异;而在添加镉的土壤中,则呈现出根>茎>叶的变化规律;土壤添加镉的量越大,杂交苏丹草各部位含镉量越高,当镉添加量为40mg kg-1土时,根、茎、叶的含镉量分别为451.9,132.5,79.4μg g-1。杂交苏丹草植株中镉含量与土壤中镉的添加量呈现为显著的直线正相关,镉的累积量呈现为先上升后下降的规律。