矿粉粒度及反应温度对高磷鲕状赤铁矿制备碳化铁的影响

基于对50根弯曲破坏钢筋混凝土圆柱低周反复试验结果的分析,建立了完整滞回环的数学表达式并推导得出等效阻尼比计算模型;以双柱墩桥梁为例,说明了建立桥梁整体结构等效阻尼比与墩柱端部塑性铰等效阻尼比关系的方法。研究表明,完整滞回环数学表达式较好地反映了弯曲破坏钢筋混凝土圆柱的滞回特性,得到的等效阻尼比模型计算结果与试验结果符合较好;采用建立的桥梁整体结构等效阻尼比与墩柱端部塑性铰等效阻尼比的关系进行pushover分析更能反映实际情况。采用等效阻尼比模型算得的目标位移与基于Rosenblueth模型和Kowalsky模型算得的位移之间存在较大差距。     

优质早籼稻产量性状分析及育种策略探讨

对115份优质早籼稻新品系的产量性状与产量的相关分析和通径分析结果表明：各产量性状均与产量呈正相关,除株高外,其余5个性状与产量的相关均达极显著或显著水平,产量性状之间存在着相互制约和相互依赖的关系;每穴穗数对产量的贡献最大（47.84%）,其次为每穗总粒数（21.86%）,再次为千粒重和结实率（分别为14.47%和9.46%）.根据分析结果,笔者认为优质早籼稻高产育种应主攻分蘖和提高分蘖成穗率,同时注意提高每穗粒数和千粒重.优质早籼稻高产（即产量达500～600kg/667m^2）育种的产量性状模式为单株有效穗8～10穗、每穗总粒数125～150粒、结实率80%以上、千粒重24～27g.     

绿豆种质资源成株期抗旱性鉴定

作物种质资源抗旱性鉴定是获得抗旱资源和挖掘抗旱基因的前提。本研究以21份绿豆种质资源为材料,采用温室内盆栽控水旱胁迫,考察不同品种单株产量、单株荚重、单株粒数、单株地上部生物量、单株生物量、根冠比等12项指标,计算各指标在旱胁迫与对照条件下的比值,运用相关性分析、隶属函数、抗旱系数和抗旱指数方法,评价绿豆成株期抗旱性,筛选抗旱优异种质。结果表明,抗旱系数与单株地上部生物量、单株总生物量、单株荚重、单株粒数、单株有效荚数在旱胁迫与对照条件下的比值呈极显著正相关,与根冠比呈极显著负相关,从而遴选出这7项指标作为绿豆成株期抗旱性鉴定的评价指标;基于隶属函数、抗旱系数和抗旱指数三者呈极显著正相关,且3种评价抗旱分级结果一致性较高,故认为抗旱指数法适宜于大规模绿豆成株期抗旱性鉴定;筛选获得高抗种质3份、抗旱种质6份、中抗种质4份、敏感种质5份和极敏感种质3份。     

应用型大学转型背景下食品工程实践类课程多元化评价体系

应用型大学转型是当前许多地方性本科院校办学的重要发展方向.在此背景下,优化食品工程实践类课程的考核评价体系,可以有效提高食品工程实践类课程的培养效率,增加食品专业毕业生的就业竞争力.     

An Evaluating Method of Human Resource Value Based on Rough Set

As the development of knowledge economic , human resource has been the core of the world economic .So searching the reasonable evaluating and managing methods becomes one of the hot issues which have been concerned by people . Traditional evaluating methods of human resource are simple and direct , but they greatly depend on people's subjective judgement and experience . In order to overcome the default , this paper puts forward the method of synthetically evaluation on rough sets, which takes advantage of the rough sets theory, the concept of information entropy and relative analysis to filter the original indexes, then to standardize the importance degree of every index and get the weight of every index. Synthetically valuation model and corresponding arithmetic are summed up. Finally the sample illuminates the validity and feasibility of this method.     

粮食粉爆事故分析与安全评估方法

通过对近20年来我国部分省市发生的重大粮食粉尘爆炸事故的分析，提出了防止粉尘爆炸的安全评价方法。     

Sources of resistance to Watermelon Chlorotic Stunt Virus in melon

Watermelon Chlorotic Stunt Virus (WmCSV) is a bipartite geminivirus residing in the genus Begomovirus (family Geminiviridae) and is whitefly transmitted ( Bemisia tabaci ). WmCSV infects members of the Cucurbitaceae , and represents a considerable threat to melon and watermelon crops in Sudan, Yemen, and Iran. One hundred twenty-eight melon accessions, mostly collected from Sudan, were screened in the open-field in Sudan under severe whitefly inoculation pressure in order to identify sources of resistance to WmCSV. One WmCSV resistant line HSD 2445-005 selected from this first screening along with 22 new melon accessions were agro-inoculated with an infectious Sudanese clone of WmCSV. Ten accessions exhibited resistance to WmCSV infection upon agro-inoculation. Six of them were confirmed to have complete resistance to WmCSV through graft-inoculation as well as multiple field trials in Sudan. These lines include the Sudanese accession HSD 2445-005, the South African accession PI 282448, and three Indian accessions: 90625, PI 124112, and PI 414723. Resistant plants exhibited no disease symptoms, and virus DNA could not be detected by hybridization with a WmCSV-specific probe.     

The Importance of the Bolivian Wild Potato Species in Breeding for Globodera pallida Resistance

Screening for resistance to the potato cyst nematode, Globodera pallida, in potatoes from. Bolivia, was carried out in 1983 and 1984, using a mixture of four nematode populations representing pathotypes Pa₁, Pa₂ and Pa₃ From the 66 accessions of 17 species and subspecies evaluated, highly resistant genotypes were identified in 21 accessions from seven species. All had Pf/Pi values of 2 or less, whereas the susceptible control, Solanum tuberosum cv. ‘Disiree’ had Pf/Pi values of more than 2G in both tests. Two diploid wild species, S. brevicaule and S. leptophyes, showed the best resistant. The geographical distributional of resistant populations and the evolution of resistance in wild potato populations are discussed.     

Durum wheat landraces from Syria

Syrian durum wheat landraces from diverse collection sites were evaluated for agronomic performance under arid conditions over two seasons at four locations, at two levels of nutrient availability.Grain yield differed considerably among locations. Within locations, significant population and fertilizer effects were demonstrated. In most cases, maximum yield was achieved by landraces, which demonstrates the breeding value of local germplasm. In a particular environment, the population effect was nonsignificant for total dry matter production, but significant for straw and grain yield. Nitrogen application was ineffective if moisture availability was the dominant growth limiting factor.Correlations between plant characteristics at evaluation and collection site characteristics were limited, and therefore, their utilization in germplasm evaluation appear limited. The negative relation between grain yield and soil nitrogen content at the collection site may be caused by the comparative disadvantage that germplasm from regions with favourable growing conditions has under low-yielding conditions.Particular environmental conditions at the collection site were no indicator for the response to changed growing conditions. Relatively high grain yields under good and adverse growing conditions excluded each other in all but two cases. Also, it was difficult to relate grain yield to regions of collection, as the response of individual landraces from a certain region to changing growing conditions differed strongly. Differentiation on the basis of landrace groups appears more promising. The Hauran landrace group provided the largest number of populations with relatively high grain yields over diverse environments.     

Field evaluation of insect-resistant transgenic Populus nigra trees

The performance of insect-resistant transgenic poplar trees (Populusnigra) expressing a Cry1Ac gene from Bacillus thuringiensis subsp. Kurstaki HD-1 against poplar defoliators was evaluated in the field at the Manas Forest Station in Xinjiang Uygur Autonomous Region during1994–1997. The results showed that the average percentage of highly damaged leaves on the transgenic trees was 10% while that on the control trees in nearby plantations reached 80–90%. The average number of pupae per m² of soil at 20cm depth in transgenic poplar plantation was 18 which was only 20% of that found in the non-transgenic control field. The number of pupae and the leaf-damage on transgenic trees described above are all far below the threshold set for chemical protection measures. The non-transformed poplar trees grown in the same plantation with the transgenic trees were also protected indicating that cross protection occurred between these two kinds of trees. Insect-resistant transgenic poplar trees have a potential application value in afforestation. This revised version was published online in August 2006 with corrections to the Cover Date.