切花菊耐热性鉴定方法研究

以8个切花菊品种为材料,通过对离体叶片进行50℃高温胁迫后,采用电导法、电阻抗图谱法测定电导率、电阻,并对大田栽培植株进行田间高温胁迫试验,比较品种间的耐热性。结果表明:电导法测得的50℃直接相对电导率、修正相对电导率和电阻抗图谱法测得的胞外电阻在品种间有明显差异,但与田间高温胁迫法测定的热害指数不完全一致。电导法和电阻抗图谱法都可以作为测定切花菊耐热性的方法,但需要结合田间耐热性观察。     

The effectiveness of grafting to improve tomato fruit quality

The possibility of applying grafting to improve fruit quality has been scarcely investigated. Different shoot tomato (Solanum lycopersicum) genotypes were grafted onto distinctly-different tomato rootstocks and the effect of the rootstock on two important fruit quality parameters, soluble solids content (SSC) and titratable acidity (TA), was studied under both non-saline and saline conditions. Increased SSC and TA in fruits from grafted plants grown under saline conditions were observed on different grafting combinations. One of these rootstocks (cv. Radja) was able to induce increases in both fruit yield and fruit quality traits of the scion. When recombinant inbred lines (RILs) from the crossing of the cultivated tomato and wild tomato (Solanum cheesmaniae) were tested as rootstocks, using the commercial hybrid ‘Boludo’ as scion, the rootstock also improved SSC and TA when grafted plants were grown under non-saline conditions. On the whole, these results show the effectiveness of grafting with respect to upgrading of fruit quality in tomato, which is of great importance as grafting is a rapid and efficient alternative to achieve this goal.     

木质地板结构与密度分布特征的CT技术检测

利用CT技术无损检测实木地板、杨木重组木地板以及毛竹重组竹地板的内部结构,并分析了三者的密度变异特征。结果表明:密度变异重组木地板＞重组竹地板＞实木地板;杨木重组木地板从表面到背面的剖面密度分布（VDP）呈现小幅下降后大幅上升的趋势,而实木地板与毛竹重组竹地板VDP无明显变化规律。CT技术能用于地板结构与密度的检测与分析,并将在木质地板质量无损检测以及重组材地板工艺优化研究中产生积极影响。      

浅谈小型电厂DCS改造

就中国石油天然气股份有限公司哈尔滨石化分公司自备电站控制系统的现状及存在的问题,提出了控制系统改造的方案,表明DCS是早期小型电厂控制系统改造的必然趋势。     

不同种源地桉树抗寒性能的比较

对来自不同种源地的6个不同种共13个桉树样品进行低温胁迫处理,通过电导率法测定它们的最低半致死温度,同时也测定了MDA、总蛋白含量、叶绿素含量、渗透调节物质如脯氨酸和可溶性糖含量等生理指标,结果发现,随胁迫时间的增加,所有样本MDA以及渗透调节物质含量均增加,赤桉增幅最大,铁木桉最小。样本MDA增加的幅度与样本抗寒能力呈负相关,渗透调节物质增加幅度则与其抗寒能力呈正相关。抗寒性较差的样本叶绿素和淀粉含量在胁迫期呈下降趋势,而在抗寒能力较强的样本中,二者与对照比较变化并不明显。通过比较各项指标发现,不仅不同种桉树的抗寒性能有显著差异,不同种源来源的同一种桉树在抗寒性能上也存在较明显差异。测试的13个不同种源地的桉树抗寒性能由高到低依次是：铁木桉（种源号：151199）〉巨桉实生苗〉巨桉EG5（组培苗）〉迪恩桉（种源号：14521）〉邓恩桉（种源号：15967）〉邓恩桉（种源号：14113）〉邓恩桉（种源号：15956）〉邓恩桉（种源号：14452）〉卵叶桉（种源号：17285）〉卵叶桉（种源号：13745）〉边沁桉（种源号：88080）〉赤桉（种源号：11911）〉赤桉（种源号：15027）。     

Histopathology and computed tomography of age‐associated degeneration of the equine temporohyoid joint

Reasons for performing study: The aetiology of temporohyoid osteoarthropathy (THO) is unknown; both primary infectious and degenerative causes have been suggested. Hypothesis: There is a significant association between increasing age and severity of temporohyoid joint degeneration. To examine the histopathology of the temporohyoid articulation in aged horses and to compare the appearance of the joint with computed tomography (CT) and peripheral quantitative CT (pQCT). Methods: pQCT scans of the temporohyoid articulations were obtained bilaterally from 31 horses (range age 1–44 years) post mortem and images were graded by 2 blinded observers on 2 occasions for the presence of osteophytes, irregularity of the joint surface and mineralisation. Eight heads had been examined previously by CT, with the images similarly graded for the shape and density of the proximal stylohyoid bones, bone proliferation surrounding the joint, mineralisation of the tympanohyoid cartilage and the relationship of the petrous temporal bone to the stylohyoid bone. Sixteen temporohyoid joints were then evaluated histologically. Results: There was significant association between the mean pQCT degeneration score and age (rho = 0.75; P<0.0001), between the pQCT and CT score (rho = 0.63; P = 0.01) and between the degenerative changes identified within each temporohyoid joint within each horse (rho = 0.81; P<0.0001). Age‐associated changes included the development of a club shape by the proximal stylohyoid bone, rounding of the synostosis with the petrous temporal bone and extension of osteophytes from the petrous temporal bone to envelope the stylohyoid head and bridge the joint. In no horse was there any evidence of osteomyelitis within the petrous temporal bone, stylohyoid bone or tympanohyoid cartilage. Conclusions: This study provides evidence that age is associated with increasing severity of degenerative changes in the equine temporohyoid joint and that similar changes are commonly found bilaterally. Potential relevance: The changes identified appear similar, albeit milder to the changes reported in horses with THO, suggesting that degenerative, rather than infectious causes may underlie the aetiology of THO. Future work should be directed at examining the histopathology of clinical THO cases.     

盐碱地区不同观赏树种电阻抗图谱参数和电导率的变化

在盐碱地区对4-6月生长期的两种不同观赏树种垂榆（Ulmus pumila var. pendula）和女贞（Ligustrum lucidum）进行电导率及电阻抗测定,分析春季和初夏生长期间在盐碱地区这两种不同观赏树种电导率和电阻抗图谱参数的变化。结果表明：在自然的盐碱环境条件下生长的垂榆和女贞,随着生长期的延长其电导率和电阻抗图谱参数均出现规律性变化,垂榆和女贞的叶片电导率均表现为先增加、后减小的变化趋势,茎均表现为先减小、后增加的变化趋势;两种观赏树种叶片的胞外电阻率表现为先增加、后减小的变化趋势,茎的胞外电阻率和弛豫时间表现为不断增加或先增加、后减小的变化趋势。相关分析表明应用电阻抗图谱参数可以表征观赏树种受盐胁迫的程度,为垂榆和女贞耐盐碱程度的电阻抗诊断提供初步的参数。     

Guidelines for in-season nitrogen application for maize (Zea mays L.) based on soil and terrain properties

Nitrogen (N) fertilizers are often applied to maize (Zea mays L.) in excess of economically optimal rates because of the uncertainty of dealing with seasonal and spatial variability. A better understanding of the relationships among field, apparent soil electrical conductivity (EC_a), elevation, slope and seasonal characteristics is therefore essential for performing optimal variable-rate N applications. This study focused on responses during the exponential growth phase, when it is critical that N supply be not limited. Measurements at high spatial resolution allowed to understand the effects of the relationships among N, EC_a, elevation, slope and season on future yield formation. The study was conducted over three years (2005-2007). Mid-season growth responses to applied N were greatest where EC_a levels were high and elevation was low in 2005 and 2007, but not in 2006. Areas with slope ≥1 degree were also more responsive to N rates. Overall best mid-season growth was found in areas of low EC_a, high Elevation and low Slope. However, the best responses to in-season N fertilization were found in areas with opposite properties (high EC_a, low Elevation and high Slope). Indeed, relatively high rates of in-season N were needed to enhance crop growth in areas of high EC_a, low Elevation and high Slope, which are characteristic of unfavourable growth conditions. In counterpart, lower N rates were sufficient for optimal growth in soils at low EC_a high Elevation and low Slope. Also, despite the fact that conditions of high soil variability were specifically selected for the study, the effects and interactions reported for soil NO₃-N content were small. The interaction of EC_a with early seasonal precipitation is likely a key relationship to consider in variable-rate N application: low-lying areas with fine soil texture showed the greatest dependence on weather for optimal N rates. Indeed, the relationships among factors influencing the response to in-season N fertilization were stronger when seasonal conditions were particularly favourable to maize growth. These results are fundamental to the establishment of in-season application rules for spatially variable N algorithms.     

温室大棚清洁装置研究

以塑料薄膜为覆盖材料的温室大棚已得到了非常广泛的应用,而粘附在塑料薄膜的灰尘影响光的入射及大棚内的气温和地温。针对透光膜温室大棚外表面的清洁工作,设计了温室大棚电动清洁机,实现温室大棚顶部的半自动清洁。该机由电机带动毛刷高速旋转,将灰尘扫入集尘盒。