气候变化对福州植物气候生产力的影响分析

利用Thornthwaite Memoriae模型估算了福州市近30多年来的植物气候生产力的状况,在分析了年均气温、降水量、风速和相对湿度年际变化的基础上,探讨了植物气候生产力的变化原因。植物气候生产力与年均气温、风速成正比,故20世纪70年代后期和90年代后,受其影响,植物气候生产力在增大;植物气候生产力与年降水量和相对湿度成反比,所以20世纪70年代前期以及80年代,植物气候生产力在逐渐降低。     

Key rock strata effecting analysis on surface boreholeshear deformation fracture

A good method for creating a surface borehole for withdrawing coal strata methane is to build before excavation and use during the whole process. But the excavation greatly affects the overlying rock strata, and when the excavation face passes through the     

磁性高分子微球及其在食品工业中的应用

磁性高分子微球是指通过适当的方法使有机高分子与无机磁性物质结合起来形成的具有一定磁性及特殊结构的微球。与传统的固定化技术相比,磁性高分子微球易于修饰、分离,目前主要应用在生物医学和生物工程学领域。重点介绍磁性高分子微球在食品工业中的应用,介绍了磁性高分子微球的制备、性质和表面修饰方法。     

响应面法优化超声波提取核桃油工艺的研究

应用超声波法辅助浸提核桃油,在单因素实验的基础上,通过Box-Benhnken中心组合实验,确定超声波辅助提取核桃油的最佳工艺条件为:正己烷作提取溶剂,液料比为7(mL∶g),提取温度53℃,超声时间48 min,超声波功率120 W,核桃油提取率达到61.91%。     

厂矿园林绿化的特点与效益评价

基于厂矿园林绿化立地条件的特点,阐述了厂矿园林绿化树种选择的原则和各类树种配置比例,并从环境效益、社会效益和经济效益3个方面,对厂矿园林绿化进行了效益评价。     

Relationships of culm surface area to other culm dimensions for bamboo, Phyllostachys pubescens

We determine the relationships of culm surface area to other culm dimensions for one of the largest bamboo species, Phyllostachys pubescens Mazel ex Houzeau de Lehaie. A total number of 150 sample culms were collected from a stand of P. pubescens in Mt. Toshima, Kumamoto Prefecture, western Japan. The culm surface area for each sample was calculated, and then the relationships of the culm surface area to basal area and product of diameter at breast height (dbh) and culm height were analyzed. The relationship between culm surface area and basal area could be described successfully by the power equation, whereas there was a linear relationship of culm surface area to product of dbh and height. Although the regression equations determined here would be useful in estimating culm surface area of P. pubescens, it is necessary to select an appropriate equation depending on the purpose and available time and labor.     

隐喻思维与中国古典园林

隐喻思维是一种观物取象,以己度物地认识、理解事物的思维方式。在园林艺术创作与欣赏中,隐喻思维拓展了园林时空,丰富了园林内涵,深化了园林意境,使园林艺术作品（每一座经典的古典园林）更为个性化、多样化、模糊化。使游览园林的人获得更为丰富的精神享受。     

西藏林芝地区森林防火阻隔带作用研究

介绍西藏林芝地区森林火灾情况,分析森林火灾多发原因．以1999～2006年在察隅、波密、林芝3县收集的8次森林火警与火灾阻隔带数据及灾后调查数据为依据,以防火阻隔带烧损程度划分地表火行为等级,共划分为4级．防火阻隔带对中等强度以下的森林地表火能起到有效的阻隔作用．提出建设防火阻隔带要根据森林分布特点科学区划,统筹安排．     

Effects of preferential flow on soil-water and surface runoff in a forested watershed in China

Preferential flow is a runoff mechanism intermediate between matrix flow and surface flow, transmitting water at high velocity through the subsurface zone. To assess the effect of preferential flow on soil-water flow and surface runoff in a forested watershed, precipitation and volumes of preferential flow, matrix flow and surface runoff were measured over a period of four years in a forested watershed in the Three Gorges area of southern China. Results show that preferential-flow hydrographs have gentler rises and steeper recessions than those for matrix flow and surface runoff. Preferential flow as a percentage of soil-water flow ranged from 2.40% to 8.72% and the maximum preferential-flow velocity exceeded as much as 5600 times that of matrix flow. This shows that preferential flow plays an important role in the movement of soil water. Preferential flow has a significant effect on peak surface runoff by increasing the surface runoff rate and accelerating the appearance of peak surface runoff. Preferential flow can also prolong the duration of surface runoff. Surface runoff was observed to be positively correlated with preferential flow. The greater the sum of rainfall amount and antecedent precipitation is, the greater the effect of preferential flow on surface runoff is.     

企业多元化经营与生产效率关系的实证研究

本文基于企业多元化经营与绩效的相关理论,以2003 -2006年中国农业上市公司公布的年报面板数据为样本,利用多元回归模型和资本与劳动的产出弹性计算全要素生产率的方法,分析了农业上市公司多元化经营与绩效的关系,并对不同类型的多元化模式与公司的生产效率关系进行实证研究。结果表明,对于农业上市公司而言,企业总体多元化水平与业绩呈负相关,且与生产效率呈反方向变动关系。从各年静态对比看,横向多元化企业的生产效率高于纵向多元化企业的生产效率;从发展趋势看,从事横向多元化会降低企业的生产效率,而保持适度的纵向多元化会促进企业生产效率的提高。