密度和复合肥对饲用玉米‘瑞德2号’产量和品质的影响

为了研究种植密度和不同施肥水平对玉米产量的影响,采用二因素完全随机区组设计,设置4个种植密度水平(6万株/hm2、7.5万株/hm2、9万株/hm2和10.5万株/hm2)和3个施肥水平(600、750、900 kg/hm2),研究了密度和施肥量对‘瑞德2号’饲用玉米产量、粗蛋白(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)等指标的影响。结果表明:随着密度的增加,单株鲜重和干重逐渐减小,而群体鲜物质和干物质产量呈先上升后下降的趋势;粗蛋白含量的增加同鲜重、干重相似,中性洗涤纤维和酸性洗涤纤维含量表现为逐渐增加。种植密度与施用复合肥的互作效应明显,种植密度9万株/hm2,施肥量为900 kg/hm2时获得最高干物质、鲜物质产量,其粗蛋白含量也为较高。     

优质春小麦不同年份播期与产量关系的试验研究

为探索优质春小麦不同播期与产量的关系,2013-2014年进行了此项研究试验。通过在本区域平年及平丰年条件下针对不同熟期春小麦品种,进行不同播期处理试验研究,研究优质春小麦不同年份播期与产量影响关系,通过本项目研究为黑龙江西部雨养农业区形成优质春小麦高产栽培模式提供依据。     

连续粒径水泥颗粒在浆体中的堆积密度

通过流动度试验发现,粒径分布不同的水泥在相同流动度时其需水量有显著差异,说明粒径分布不同的水泥其堆积密度不同;推导了连续粒径粉体在浆体中的堆积密度计算公式,并通过试验对该公式进行了验证.     

Effects of Dry Density and Grain Size Distribution on Soil-Water Characteristic Curves of Sandy Soils

The soil-water characteristic curve (SWCC) of soil plays the key roll in unsaturated soil mechanics which is a relatively new field of study having wide applications particularly in Geotechnical and Geo-environmental Engineering. To encourage the geotechnical engineers to apply unsaturated soil mechanics theories in routine practice, numerical methods, based on the SWCC and saturated soil properties, have been developed to predict unsaturated permeability function and unsaturated shear strength properties which are expensive and time consuming to measure in laboratories. Further, several methods have been proposed to predict the SWCC in order to avoid difficulties in measuring the SWCC in laboratories. It is time consuming and it may require special techniques or apparatus to measure the SWCC in laboratories. However, it is important to have laboratory measured data of SWCCs to enhance and verify the proposed numerical methods. Hence, employing a Tempe pressure cell apparatus, the present study aims to investigate the effects of dry density and grain-size distribution on the SWCCs of sandy soils. Drying and wetting SWCCs were obtained for four sandy soils with different dry densities. The test data were best-fitted using the Fredlund and Xing (1994) equation and found that the fitting parameter, a, increases linearly with increasing the air-entry value of the SWCC and the fitting parameter, m, decreases with increasing the residual suction of the SWCC. The results revealed that soils with a low density have lower air-entry value and residual suction than soils with a high dry density. Further, the maximum slope of drying SWCC and hysteresis of drying and wetting SWCCs decrease with increasing density of soil. The air-entry value, residual suction, and hysteresis (the difference between the drying and wetting SWCCs) tends to decrease when the effective D₁₀ of the soil increases. A soil with uniform grain-size distribution (the steeper slope in grain-size distribution) has a less hysteresis and a greater slope of drying SWCC than those of a non-uniform soil.     

豇豆收获前后种子劣变的抗性研究

不同豇豆种质在种子形成过程中对不良自然环境的适应能力和贮藏抗性不同,严重制约着豇豆优质种子生产和推广。了解豇豆品种的田间抗劣变能力,对指导新品种选育、种子生产和品种推广具有十分重要的意义。本研究采用甲醇胁迫法和温箱蚀化法对5份豇豆种质进行收获前和收获后种子劣变的鉴定。综合各项指标的检测结果发现:‘丰豇十号’种质适应性差,气候对其生长影响较大,不适宜大面积推广。‘大润发’和‘丰豇青优’综合表现最佳,对气候的适应较强,适合大面积推广。     

草坪喷播技术的研究与应用

人类社会经济活动的频繁发生,促进了社会进步,但也带来了生态环境问题。如：裸露边坡问题,不仅给城市景观带来了不良影响,还产生了一定的安全隐患。因此,边坡生态防护设计必须引起足够的重视。文章重点阐述了草坪喷播技术的具体应用。     

草坪喷播技术的研究与应用

人类社会经济活动的频繁发生,促进了社会进步,但也带来了生态环境问题。如：裸露边坡问题,不仅给城市景观带来了不良影响,还产生了一定的安全隐患。因此,边坡生态防护设计必须引起足够的重视。文章重点阐述了草坪喷播技术的具体应用。     

砂岩颗粒度对玻璃熔制的影响

以不同颗粒度砂岩和不同颗粒级配砂岩配料，通过对所熔制的样品进行ＤＴＡ，ＴＧ和ＸＲＤ分析，探讨砂岩颗粒度和颗粒级配对硅酸盐形成和熔融过程的影响，以及掺水后不同颗粒度砂岩配合料的硅酸盐形成反应变化．研究结果表明，砂岩下限控制在１５０目的掺水配合料无明显细粉团聚现象，具有不掺水细颗粒砂岩配合料的硅酸盐形成反应特点和良好的熔制效果     

《滇南本草》研究概述

《滇南本草》是云南历史上价值最大,影响最广的地方性本草,记载了兰茂多年的临床实践用药、方剂及病案,是兰茂在中医理论指导下,结合云南本地各少数民族特点总结出来的智慧结晶,对后世医药的发展产生了深远影响。近些年越来越多的学者对《滇南本草》进行不断的挖掘整理,并通过临床的实践,不断的验证及扩充《滇南本草》的理论,为充分挖掘兰茂著作《滇南本草》的学术思想,笔者从理、法、方、药视角对《滇南本草》的书籍和文献进行收集、整理、分析、总结,以期为《滇南本草》的进一步研究提供参考。     

Density and Outer Urban Development in Melbourne

The issue of residential density is again an important issue in strategic land use planning in Australia. For decades, Australian planners generally have accepted the conventional position that increasing the density of urban settlement on the urban fringe will achieve negligible land savings because the amount of land required for non-residential purposes remains constant. This position continues to affect government policy and practice. This article analyses the role of residential density in debates about urban form, and shows the potential for land savings from different scenarios of increased residential density and urban design. The article demonstrates the capacity for increased residential densities in new outer suburbs of cities to significantly contain outward urban growth.