漠大原油管道SCADA通讯中断原因及应对措施     

何兆洋  尚义  何丽萍  黎春  殷素娜 《油气储运》2014,(5):501-504

漠大原油管道SCADA控制系统通讯中断频繁,严重威胁管道的安全运行。基于漠大原油管道通讯中断数据,统计分析了通讯中断时长、通讯中断类型的比例分布特性,结果表明,时长2～12 h的通讯中断频次最高,占总中断次数的44.3%。探讨了漠大原油管道通讯中断原因,其中天气因素与设备故障是导致通讯中断的主要因素,共导致了74.4%的通讯中断时长。为了降低通讯中断频次,结合漠大原油管道的运营现状,提出了4项管理措施：加强天气监控及现场作业管理,做好应急预案;完善管道保护程序;积极开展维护修复工作;加快推进加格达奇以南光缆割接与测试工作。  相似文献   

Contribution of incident solar radiation on leaves and pods to soybean seed weight and composition     

《European Journal of Agronomy》2016

The weight and composition of soybean seeds (Glycine Max L. Merrill) depend on changes in carbon and nitrogen assimilate supply during grain filling. Soybean pods and seeds are green, evidencing their capacity to capture light. However, the current physiological knowledge does not consider any effect of incident solar radiation reaching the pods on seed weight and composition. The objective of this work was to investigate the response of seed weight and composition to changes in assimilate supply from leaves, to the incident solar radiation reaching the pods and to the combination of both, changes in assimilate supply from the leaves and incident solar radiation on pods of soybean plants. Field experiments were performed during two growing seasons at Balcarce, Argentina. Treatments modified the amount of assimilates supplied by the leaves (plant shading, defoliation), the solar radiation reaching the pods (pod shading) or both (defoliation and pod shading) during seed filling. Plant shading and defoliation reduced seed weight, oil concentration and oil and protein content and increased the concentration of saturated and poli-unsaturated fatty acids while reduced oleic acid percentage. Pod shading increased the concentration of stearic acid and reduced the concentration of linolenic acid. When pods were shaded on defoliated plants, seed weight and oil and protein content decreased while fatty acid composition was similar to values obtained under defoliation treatment. Based on these results, a conceptual model that considers photoheterotrophic nature of reproductive structures of soybean is proposed. Seed weight, oil and protein content and oil fatty acid composition depended on assimilate availability for the seeds. The response of oil and protein content to assimilate supply depended on whether leaves were present or not. The effect of solar radiation incident on pods depended on the amount of assimilates available for the seeds: (i) when carbon allocated was low (defoliation treatments), pods contributed to seed carbon economy but solar radiation incident on them did not affect fatty acid composition; (ii) when carbon allocated to the seeds was high (intact plants), contribution of pods to seed carbon economy was not significant, but the amount of solar radiation incident on pods produced significant changes in fatty acid composition.  相似文献   

鸡新城疫油佐剂灭活疫苗的研究   总被引：3，自引：2，他引：3  

郑世兰  姜北宇 《华北农学报》1995,10(3):115-123

采用ＮＤ Ｌａｓｏｔａ株为种毒，福尔马林为灭活剂，７号白油为佐剂，吐温８０、司本８０为乳化剂，硫柳汞为防腐剂，高压匀浆泵为乳化工具，研制出ＮＤ油佐剂灭活疫苗。其剂型为双相型（Ｗ／Ｏ／Ｗ），呈稀薄乳状液，粒度为１ｕｍ左右，粘度≤１ｓ，通针性好。４￣８℃有效保存期１年。效力≥７０ＰＤ５０，最早产生免疫时间为１２天（１００％保护），生产中常用免疫剂量为２月龄内每只０．５ｍｌ，２月龄以上每只１．０ｍｌ皮下  相似文献   

原生质体载体技术在马铃薯育种中的应用     

张延红  何春雨  谢从华  于品华  柳俊 《中国农学通报》2005,21(9):43-46

综述了原生质体载体技术在育种中的应用:体细胞杂交、以原生质体为受体细胞的DNA直接导入转化、体细胞无性系变异、胁迫耐受系的选择,同时针对马铃薯的生物学特性、育种现状及其原生质体方面的研究现状,提出利用原生质体载体技术进行马铃薯育种的优势和切实可行性。  相似文献   

表面油流法显示螺旋离心泵内部流动的研究   总被引：2，自引：2，他引：2  

郭乃龙  关醒凡 《农业机械学报》1997,28(3):29-34

对螺旋离心泵叶轮、进水节和进水节与蜗壳交界处的部分端面做了表面油膜、油点试验。通过流谱分析，揭示了表面奇点、分离线与再附着线等流动特征，研究了螺旋离心泵内部流动规律，进而提出了改进螺旋离心泵结构的设想。  相似文献   

Agricultural practice changes with cultivating genetically modified herbicide-tolerant oilseed rape     

F. Graef  U. Stachow  A. Werner  G. Schütte 《Agricultural Systems》2007

To facilitate weed suppression, oilseed rape or canola (Brassica napus) has been genetically modified (GM) over the last two decades to incorporate herbicide tolerance (HT). The introduction of oilseed rape in commercial agriculture raises concerns about potential adverse agronomic and environmental effects linked to both the genetic modification and altered agricultural practice. How will this new crop modify the existing cropping practice? What are the potential agro-environmental implications of its introduction? This paper analyses and schematises recorded and conceivable agricultural practice changes with GMHT oilseed rape introduction and its likely agro-environmental effects. It develops a conceptual systematics of influencing factors, subsequent practice changes and likely agro-environmental effects. The results can be used to design the mandatory monitoring of adverse GM crop effects.  相似文献   

基于GIS的长江中游油菜种植区土壤养分及pH状况   总被引：7，自引：0，他引：7  

丛日环  张智  郑磊  苗洁  任意  任涛  李小坤  鲁剑巍 《土壤学报》2016,53(5):1213-1224

为了掌握长江中游油菜种植区土壤养分状况,在湖北、湖南、江西三个省份调查和取样分析5 463份土壤数据的6个指标(土壤有机质、全氮、有效磷、速效钾、有效硼和pH),基于Arc GIS平台,采用Kriging插值法分析4个不同油菜种植区域(二熟制山地区、二熟制平原区、三熟制山地区、三熟制平原区)的土壤养分状况。结果表明,长江中游油菜种植区土壤有机质、全氮和有效磷均处于适宜/丰富的含量水平,基本没有5级和6级水平的有机质、全氮、有效磷分布。从不同区域来看,以上3个养分指标总体均表现为三熟制地区养分含量高于二熟制地区。长江中游仍有1.82×10~5 hm~2区域土壤速效钾处于缺乏的水平(30~50 mg kg~(-1))。土壤有效硼含量仍有待提高,尤其是在三熟制地区,土壤有效硼缺乏(5级和6级)的比例仍高达13.6%~20.4%。土壤pH多集中在6.0左右,但是三熟制地区仍然有较高比例(约35.7%)的土壤pH处于4.5~5.5。综上所述,长江中游不同种植区域土壤养分性状存在差异,尤其是三熟制地区仍有相当比例需要提高土壤有效硼和改良酸性土壤。  相似文献   

Organic acid content and composition of the olive fruits during ripening and its relationship with oil and sugar     

Cevdet Nergiz  Pelin Günç Ergönül 《Scientia Horticulturae》2009

In this work, the contents of oil, sugar and organic acids of olive fruit samples (Domat, Memecik and Uslu) were determined by using HPLC at different maturation stages. Olive fruit samples presented a common organic acid profile, composed of four constituents: oxalic, citric, malic and succunic acids. Total organic acid content of Domat variety was found to be 4787.1 ± 4.53 mg/100 g in January. Memecik variety had the highest value at the beginning of the ripening period (6385.08 ± 4.90 mg/100 g). The amount of organic acid in Uslu variety reached up to the value of 10942.5 ± 30.41 mg/100 g. The results were evaluated statistically to determine relationship between the oil, sugar and organic acid content in three olive varieties during maturation. A positive correlation was found between the total sugar and organic acid (r = 0.54, p < 0.01) whereas a low positive correlation was observed between the contents of oil and total organic acids (r = 0.46, p < 0.05) in olive varieties.  相似文献   

Seed yield and water use efficiency of canola (Brassica napus L.) as affected by high temperature stress and supplemental irrigation     

Abolfazl Faraji  Nasser Latifi  Amir Hossain Shirani Rad 《Agricultural Water Management》2009,96(1):132-140

The effects of high temperature stress and supplemental irrigation on seed yield and water use efficiency (WUE) of canola (Brassica napus L.) were studied in a field experiment conducted for 2 years. The experiment was a randomized complete block design arranged in split plot, conducted at Agricultural Research Station of Gonbad, Iran. It was arranged in two conditions, i.e. supplemental irrigation and rainfed. Two cultivars of canola (Hyola401 and RGS003) as subplots were grown at five sowing dates as main plots. The sowing dates were 9 November, 6 December, 5 January, 4 February and 6 March in 2005-2006 and 6 November, 6 December, 5 January, 4 February and 6 March in 2006-2007, to have a wide range of environmental conditions around flowering and seed filling periods, and to coincide reproductive stages of the crop with high temperature stress. Seed yield was improved due to field management practices, such as supplemental irrigation and optimum sowing date. Supplemental irrigation was an efficient practice to mitigate water stress, and to increase aboveground dry matter and seed yield. There was a strongly negative relationship between seed yield and air temperature during reproductive stages. Delay in sowing led to more rapid developmental of canola, decreased aboveground dry matter, leaf area index (LAI), harvest index (HI), WUE, and seed yield. Achieving a high aboveground dry matter was an essential prerequisite for high reproductive growth and a high seed yield. Greater seed yield and WUE at first sowing date were associated with greater LAI and aboveground dry matter, and lower temperatures during reproductive stages. The results support the view that WUE can be used as an indirect selection criterion for seed yield in genotypic selection.  相似文献   

PASSAT领驭2.0自动变速箱偶尔出现紧急运行状况检修分析     

袁媛  刘跃明  陆国达 《拖拉机与农用运输车》2009,36(3)

结合PASSAT领驭2.0轿车偶尔出现自动变速箱Ⅲ挡运行的紧急运行状况故障,分析了故障码、有关传感器电路,以及故障产生的原因,据此找出了故障点,并排除了故障。  相似文献