宁陕县城区生态环境治理工程初探

介绍并分析宁陕县城区及周边地区“8．29”惨遭洪水、泥石流袭击,生态环境遭到严重破坏的情况,提出了城区生态环境方面存在的问题,同时在规划设计方案中运用生态治理技术,以工程造林的方法,探求城区生态环境建设的新模式。     

计算机计算含未知量元素行列式的“保值回跳”法

本文探讨了用计算机计算含未知量元素行列式的方法与途径,提出了“保值回跳”的思想。并提供了以该思想为基础而编制的空间桁架结构位移响应关于截面设计变量显式表达式程序计算的若干算例。     

烫漂及冻结对青头菌营养价值的影响

研究了在不同的烫漂温度和烫漂时间下青头菌过氧化物酶(Peroxidase，POD)活性的变化．烫漂及冻藏对青头菌过氧化物酶活性、氨基酸、矿质元素、维生素及氨基酸态氨等成分的影响结果表明：采用95～96℃烫漂温度效果最好，在4min内过氧化物酶活性降低了95．5％；烫漂及冻藏都使青头菌营养成分受到不同程度的损失建议采用一70℃以下温度不经烫漂而冻结，冻品在-26℃冰箱中贮藏12个月，其营养价值保持很好。     

不同生长年限王草的营养价值研究

本文对生长第1、2、3年的王草在100cm高度时刈割的营养成分及其体外干物质、有机物降解率进行分析研究。结果表明:不同生长年限王草第1年的粗蛋白质显著高于第2、3年(P<0.05),而中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)显著低于第3年(P<0.05)。干物质、有机物的降解率第1年最高,第3年的最低,但差异不大。     

双低菜籽粕在饲料中的应用

双低菜籽粕具有高产优质的特点,其饲用品质优于普通菜籽粕,营养价值与豆粕相当,被广泛应用于饲料。为了更有效开发其对饲料业和养殖业的应用潜力,本文就双低菜籽粕的营养价值和在动物饲用方面进行的一系列的基础性研究作一简要介绍。     

转基因苜蓿研究进展

就苜蓿基因工程在育种上的研究、转基因技术在苜蓿上的进展做了简要介绍。     

Designating a greenbelt around the city of Riga, Latvia

Latvian legislation demands that forest protection belts are established around all cities and towns. The main goal of a protection belt is to provide suitable opportunities for recreation to urban dwellers and to minimise any negative impacts caused by urban areas on the surrounding environment. Legislation states the main principles to be adopted, which include the maximum area of protection belts, their integration in territorial development plans and restrictions placed on forest management activities. The largest part of the forest area around Riga is owned by the municipality of Riga, which, as a result, has two competing interests: to satisfy the recreational needs of the inhabitants of Riga, and to maximise the income from its property. In order to compile sufficient background information to solve this problem, the Board of Forests of Riga Municipality initiated the preparation of a proposal for the designation of a new protection belt.The proposal was based on the development and application of a theoretical framework developed during the 1980s. The analysis of the recreational value of the forest (5 classes of attractiveness) was carried out based on categories of forest type, dominant tree species, dominant age, stand density, distance from urban areas and the presence of attractive objects. Information was derived from forest inventory databases, digital forest maps and topographic maps. Additional information was digitised and processed using ArcView GIS 3.2. Local foresters were asked about the recreation factors unique to different locations, such as the number of visitors and the main recreation activities. From a recreational point of view and taking into account legal restrictions and development plans for the Riga region, it was proposed to create three types of zones in the forest: a protection belt, visually sensitive areas and non-restricted areas.     

人为影响下古尔班通古特沙漠小尺度生态环境变化

随着沙漠中油气资源勘探开发、公路建设和重大工程相继实施 ,对生态环境的人为影响日益加深。本文以重大工程实验点为例 ,通过研究对比工程影响区内人工沙垄和自然沙垄的砂质新成土理化性状和植被群落特征 ,指出了沙漠生态环境在人为干扰下发生的一系列变化 ,以及受损生态环境在人们采取积极补救措施的情况下所具有的自然修复能力     

Bone marrow-derived stromal cells and cartilage tissue engineering

Articular cartilage repair is one of the most challenging issues which remains to be resolved in clinic work. Discovering of bone marrow stromal cells (BMSC) and its application in tissue engineering provide new methods for the treatment of cartilage defects. High seeding density, appropriate cytokines and three-dimensional culture play important roles in the process of inducing BMSC differentiating into chondrocytes, suitable scaffold is also essential in reconstructing cartilage in vitro by methods of tissue engineering.     

不同碳源对虎奶菇菌核蛋白质营养价值的影响

测定了四种碳源对虎奶菇菌核蛋白质营养价值的影响。结果表明，以玉米淀粉为碳源，虎奶薅菌蛋白质的化学评分，必需氨基酸指数，生物价和营养指数分别为11．63、69．80、64．40和9．98，均居四种参试碳源的第一位；氨基酸评分和氨基酸比值系数分分别为14．55和12．45，均居四种参试碳源的第二位，这些结果证实，以玉米淀粉为碳源，虎奶菇菌核蛋白质营养价值高，值得推广应用。