青海野生马蔺种子处理试验

采用层积处理法、浸种＋药剂处理、层积＋药剂处理和清水对照的单因数随机区组设计,测定青海野生马蔺的起出苗率和苗高,结果表明：层积＋药荆处理、层积处理、浸种＋药剂均可以明显提高马蔺种子的出苗率,但以层积＋药剂处理的出苗率最好。层积＋药剂处理可以明显提高马蔺植株的苗高,层积处理、直接浸种＋药剂处理没有提高马蔺植株的苗高的作用。层积＋药剂处理可以作为野生马蔺种子处理的首选。     

杂交中稻组合冈优22母本直播高产制种技术

综合分析了冈优２２母本直播高产制种技术增产节支效果,对父母本主要特性和经济技术指标,以及对播差期安排,母本播管和“九二０”施用等高产制种技术关键作了阐述。     

Revegetation of mining spoils by seeding of woody species on Ghiona Mountain,central Greece

The reforestation potential of calcareous bauxite mining spoils by seeding was examined on experimental plot established at Strofi Koukouvista 5, Mount Ghiona in Central Greece. The experiment consists of three species (Pinus nigra, Robinia pseudoacacia, and Spartium junceum) with four sowing treatments and two sowing seasons (autumn and spring). The treatments were: broadcasting (B); broadcasting and soil cultivation (BC); broadcasting with straw mulching and straw binding with asphalt emulsion (BM); broadcasting with soil cultivation, straw mulching and straw binding with asphalt emulsion (BCM). In all cases sowing in spring was better than in autumn. Only Spartium junceum has germinated and survived in autumn, but less than in spring. The most effective treatments for Robinia pseudoacacia and Pinus nigra are BM and BCM while for Spartium junceum even simple broadcasting shows good results although the best are achieved with treatments BC, BM and BCM. The findings show that reforestation by sowing could be effective for some species, but further experimentation with other species and methods is recommended. Copyright © 2002 John Wiley & Sons, Ltd.     

高温季节壮苗复配剂对黄瓜幼苗的影响

以培育黄瓜壮苗为目标．选用矮壮素、甲壳质、黄腐酸三种药剂复配,播种前喷施在基质内,研究其对黄瓜幼苗的影响,为生产应用提供理论依据。     

Biosynthesized metallic nanoparticles as fertilizers: An emerging precision agriculture strategy

Nanofertilizers increase efficiency and sustainability of agricultural crop production. Due to their nanosize properties, they have been shown to increase productivity through target delivery or slow release of nutrients, thereby limiting the rate of fertilizer application required. Nanofertilizers can be synthesized via different approaches ranging from physical and chemical to green (biological) synthesis. The green approach is preferable because it makes use of less chemicals, thereby producing less chemical contamination and it is safer in comparison to physicochemical approaches. Hence, discussion on the use of green synthesized nanoparticles as nanofertilizers is pertinent for a sustainable approach in agriculture. This review discusses recent developments and applications of biologically synthesized metallic nanoparticles that can also be used as nanofertilizers, as well as their uptake mechanisms for plant growth. Toxicity concerns of nanoparticle applications in agriculture are also discussed.     

矮壮素对高温期辣椒秧苗质量的影响

为了解决秋延晚栽培过程中高温多湿气候条件下辣椒育苗难的问题,本课题组进行了秋延晚栽培育苗中用矮壮素控制育苗的试验。结果表明:育苗期应用矮壮素,有调节植株生殖生长和营养生长关系和提高产量的作用。处理的最适时期为分苗期,矮壮素的适用量为10g/m2。     

离散与连续测量齿形误差的分析比较

介绍了渐开线齿形误差的两种测量方法--离散测量法和连续测量法.通过测量实例较详细地介绍了用工具显徽镜进行离散测量齿形误差的原理和方法,并将其测量结果与连续测量结果进行比较和误差分析.其结果是离散测量所得测量误差较连续测量大,因而提高了出厂齿轮的精度要求,虽然对产品会产生一定的"误废”概率,但对保证齿轮的出厂质量是有好处的.所以此法适合中小厂家应用.     

The Effect of Seeding Rate and Nitrogen Fertilization on Barley Yield and Yield Components in a Cool Maritime Climate

Soil and climatic conditions in Newfoundland are on the margins of agricultural capability, and almost all feed grain is imported. The overall objective of this work was to develop guidelines for the production of barley in Newfoundland, with the goal of establishing modern cropping recommendations. We conducted a 4-year study near St. John's to examine the effect of seeding rate and topdress ammonium nitrate (N) fertilization rate on Chapais six-row barley ( Hordeum vulgare L.) yield components and grain yield. Increasing seeding rate from 200 to 380 seeds m^–2 did not alter grain yield in any year. Increasing topdress fertilization from 0 to 60 kg N ha^–1 increased spike density m^–2 at harvest, resulting in linear increases in grain yield in all years. Highest N rates had greatest lodging in two years. Based on our results, agronomic recommendations for eastern Newfoundland now include barley seeding rates of 250 ± 50 seeds m^–2, with topdress applications up to at least 30 kg N ha^–1.     

修配环尺寸的确定方法研究

对采用修配法达到装配精度时修配环尺寸的确定方法进行了研究 ,给出了两个计算修配环尺寸的公式。应用该公式 ,可在最小修配量为零或不为零的任何情况下 ,简捷方便地确定出修配环的尺寸。     

声光调Q YAG脉冲激光修锐和整形超硬磨料砂轮

超硬磨料砂轮的修整是制约其优良磨削性能发挥的瓶颈。本文采用声光调Q YAG脉冲激光径向辐照砂轮表面，利用自己开发的一套在线检测闭环控制系统，控制激光脉冲的输出，对砂轮表面进行修整，达到了理想的整形精度，并发现可同时实现修锐，使超硬磨料砂轮的激光修锐和整形可合二为一，通过单脉冲试验研究总结出激光参数和工艺参数对砂轮修整效果的影响特点，选择优化的参数进行修整，获得了较好的修整效果。