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实地调查了湛江市23个代表性园林绿地中地被植物种类及其配植现状,共记录了145种(含品种),隶属于64科108属。园林配植上以片植、丛植为主,垂直绿化品种较少。调查发现,部分地被植物的管理养护水平不到位,配植方式需继续提高。在此基础上,建议今后扩大乡土地被植物在园林绿化中的应用,考虑植物生长环境的适应性,加强管养,提高地被植物配植的多样性。 相似文献
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近景摄影测量和近年来发展起来的三维激光扫描技术已广泛用于树木三维数据的获取,通过近景摄影测量技术和三维激光扫描方法获得的数据各有优缺点,但它们优势互补构成获取立木数据强大的工具。三维激光扫描有快速获取数据的优点,缺点是容易留下没扫描的空白区域(扫描漏洞);摄影测量能根据人们的主观愿望布置测量控制网,很灵活地采集数据点,能够补充扫描漏洞没有数据点的缺陷,缺点是因布置测量控制网,要增加劳动强度,再者在影象上灰度变化不明显的部位无法获得同名像点,在一定程度上制约着三维建模的精度。试图探讨利用近景摄影测量辅助三维激光扫描的数据采集技术来恢复单木空间实体,计算胸径、任一处的直径、树高、树冠体积等测树指标,最后得出材积方程,服务于森林资源的精准监测。 相似文献
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Cereals β-glucans are linear homopolysaccharides of consecutively linked (1→4)-β-d-glucosyl residues (i.e. oligomeric cellulose segments) that are separated by single (1→3)-linkages. β-Glucans display all the functional properties of viscous and gel forming food hydrocolloids combined with all the physiological properties of dietary fibres. This review focuses on the relationships between the molecular–structural characteristics of β-glucans and their physicochemical properties in aqueous dispersions and in food systems as well as their physiological functions in the gastro-intestinal tract. The physical properties of β-glucans, such as solubility and rheological behaviour in the solution and gel states, are controlled by their molecular features, such as their distribution of cellulosic oligomers, their linkage pattern and their molecular weight as well as by temperature and concentration. The technological and nutritional functionality of β-glucans is often related to their rheological behaviour. Incorporation of β-glucans into various products (bread, muffins, pasta, noodles, salad dressings, beverages, soups, reduced-fat dairy and meat products) showed that attributes, such as breadmaking performance, water binding and emulsion stabilising capacity, thickening ability, texture, and appearance appear to be related to the concentration, molecular weight and structure of the polysaccharide. The health benefits of β-glucans, such as reducing blood serum cholesterol and regulating blood glucose levels, are also correlated with the amount and molecular weight of the solubilised β-glucans in the gastro-intestinal tract. 相似文献
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综述了微生物菌在轻型基质中的应用与研究,从有机质降解、调控基质理化性状、促进植物生长与发育等方面展开论述,分析了微生物菌剂在基质中的作用机制与存在的问题。最后,根据问题提出了微生物菌剂在基质应用中的发展方向,为新型菌剂基质的开发提供了指导。 相似文献
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为了进行中兽药散剂检测方法学研究,试验使用HPLC法和薄层色谱法对中兽药散剂中非法添加喹乙醇、乙酰甲喹进行检查。48批中兽药散剂中,13批药品中检出乙酰甲喹,含量在0.34—42.64mg/g范围内;1批药品中检出喹乙醇,含量为15.30mg/g。两种方法检查结果完全吻合。 相似文献
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小型履带式拖拉机的发展方向 总被引:1,自引:1,他引:0
周夏南 《拖拉机与农用运输车》2009,36(3)
通过对国内、国外市场的调查、研究和分析,详细阐述目前小型履带拖拉机的发展方向及应用领域。 相似文献
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