草花育苗大棚定时灌溉系统研制     

胡彦福  谢守勇  刘丽 《节水灌溉》2007,(5):30-32

研究了采用DS12C887提供实时时钟、单片机AT89S51进行控制的草花育苗大棚灌溉系统.该控制系统采用模块化的设计,把时钟单元设计成了一个单独的模块,这样可以向任意多的定时单元提供实时时钟信号,所以控制系统有很好的扩展性,可以根据大棚的数目来扩展控制器的数目.通过现场调试,其运行满足实际要求.  相似文献   

厌氧氨氧化工艺在废水脱氮领域中的应用进展   总被引：2，自引：0，他引：2  

宫玥  吴立波 《中国沼气》2007,25(5):3-7

厌氧氨氧化是一种全新的生物脱氮工艺。对于处理低碳氮比废水,与传统方法相比,它具有节省氧耗、无需外加有机碳源、污泥产量低等优点。近年来,随着基础研究的逐渐深入,各国学者开始将研究视角转向厌氧氨氧化工艺的实际应用。本文对该工艺在消化污泥上清液、垃圾渗滤液等实际废水脱氮研究中的进展进行了综述,并指出了目前存在的问题和今后的研究方向。  相似文献   

全国农机监理信息系统建设初探     

周中林 《农机化研究》2006,(11):46-49

农机安全监理担负着我国数以千万计的农业机械及其驾驶员的行政管理任务,相应的法律法规要求采用计算机管理系统来对此进行处理并能够及时地将有关信息传送到全国农机监理信息系统。由于全国统一的农机监理信息系统尚未建立,因此提出了构建全国农机监理信息系统数据库标准,即采用B/S模式进行应用程序开发,通过多种网络连接全国各地农机监理业务计算机,从而实现信息共享与网上办公的解决方案。  相似文献   

基于CLIPS的农业灌溉专家系统研究   总被引：1，自引：0，他引：1  

陈大春  雷晓云  马英杰  木拉提  何春梅 《中国农村水利水电》2007,(1):41-42,47

在干旱区高效用水灌溉决策支持系统研究过程中,农业灌溉过程中的很多问题无法用数学模型来求解,而必须使用农业专家的专家知识来对其进行解答。而早期由于专家系统不普及和开发困难等原因,致使农业灌溉专家系统应用不多。在对现行诸多专家系统进行详细了解后,决定采用CLIPS专家系统作为农业灌溉专家系统的支持平台。采用CLIPS组件和Visual C 语言开发出了农业灌溉专家系统,解决了农业灌溉过程中的诸多问题。同时介绍了将CLIPS组件嵌入到Visual C 中的方法。  相似文献   

扭振减振器对曲轴弯曲和纵向振动的影响研究     

段秀兵  郝志勇 《拖拉机与农用运输车》2005,(5):32-34

以一台多缸柴油机为例,采用结合有限元法(FEM)的多体系统仿真(MSS)方法,研究了扭转振动减振器振动对曲轴弯曲、纵向振动的影响;实验测量了有无扭振减振器时的曲轴自由端的弯曲和纵向振动,其与计算结果吻合得较好。  相似文献   

Expression of cathepsin C and tumor necrosis factor-α in human coronary artery and their relationships with coronary heart disease     

ZHANG Qiong  WAN Chang-wu  YU Yan-ni  XIA-Bing  LIU Jiang-jin  ZHANG Qiao-jun  LI Zhu  WANG Cheng-fei  DAI Jia-lin  WANG Jie 《园艺学报》2021,36(12):2133-2138

AIM To explore the possible mechanism of cathepsin C （CTSC） and tumor necrosis factor-α （TNF-α） in coronary heart disease （CHD） by detecting the protein expression of CTSC and TNF-α in human coronary artery tissue. METHODS The coronary artery tissues from 52 cases of CHD and 25 cases of accidental death without any heart disease in the Forensic Judicial Expertise Center of Guizhou Medical University from October 2018 to December 2019 were collected as CHD group and control group, respectively. The coronary artery stenosis and intimal plaque formation were examined by histopathology, the protein expression of CTSC and TNF-α was determined by Western blot, and the intracellular expression of CTSC and TNF-α was analyzed by immunohistochemical staining. RESULTS The results of HE staining showed that the intima of coronary artery in control group was smooth, and no thickening or stenosis was observed. In CHD group, the intima thickened irregularly, atherosclerotic plaques formed, the intima became thinner and the lumen showed eccentric stenosis in varying degrees （P<0.05）. The results of Western blot showed that the expression of CTSC and TNF-α in CHD group was significantly higher than that in control group （P<0.05）. Immunohistochemical staining showed that both CTSC and TNF-α were expressed in the cytoplasm of foam cells, and their positive expression was significantly higher than that in control group （P<0.05）. The results of Pearson moment correlation analysis showed that there was positive correlation between the expression of CTSC and TNF-α in CHD （r²=0.743, P<0.05）. CONCLUSION The up-regulated expression of CTSC in coronary artery tissue may promote the expression of TNF-α and affect the occurrence and development of CHD.  相似文献   

Legume–barley intercropping stimulates soil N supply and crop yield in the succeeding durum wheat in a rotation under rainfed conditions     

《Soil biology & biochemistry》2015

Legume–cereal intercropping is increasingly being appreciated in dryland areas, where severe climatic conditions and intensive agricultural practices, generally dominated by continuous cereal cultivation, determine depletion of soil nutrient resources and decline of soil fertility. This research aimed to assess whether and to what extent a newly introduced legume-based intercropping system is able to ameliorate the biological fertility status of an arable soil in a way that is still noticeable during the succeeding durum wheat cropping season in terms of changes in bacterial community structure, soil C and N pools, and crop yield. A field experiment was carried out under rainfed conditions in Southern Italy on a sandy clay loam soil cultivated with durum wheat following in the rotation a recently established grain legume (pea, faba bean)–barley intercropping. Soil chemical, biochemical and eco-physiological variables together with compositional shifts in the bacterial community structure by LH-PCR fingerprinting were determined at four sampling times during the durum wheat cropping season. Soil fertility was estimated by using a revised version of the biological fertility index. Results showed that even though the microbial biomass was significantly altered, the preceding legume intercrops stimulated C-related functional variables thus leading to an increased release of mineral N, which was larger in crop treatments succeeding pea-based than faba bean-based intercropping. The increased N made available in soil enabled the succeeding durum wheat to achieve an adequate grain yield with a reduced N-fertilizer use. Soil type and environmental conditions rather than crop treatments were major determinants of bacterial community structure. The biological fertility status was not varied, suggesting that in intensively managed rainfed areas long-term crop rotations with intercropped legumes are needed to consistently ameliorate it.  相似文献   

Is Discrimination of 13C in Potato Leaflets and Tubers an Appropriate Trait to Describe Genotype Responses to Restrictive and Well‐Watered Conditions?          下载免费PDF全文

D. A. Ramírez  J. L. Rolando  W. Yactayo  P. Monneveux  R. Quiroz 《Journal of Agronomy and Crop Science》2015,201(6):410-418

Selection for drought tolerance entails prioritizing plant traits that integrate critical physiological processes occurring during crop growth. Discrimination against ¹³C (?) in leaflets (?_leaflet) and tubers (?_tuber) was compared under two water regimes in two potato‐improved varieties selected to maintain yield under drought conditions (Unica and Sarnav) and one drought susceptible European cultivar (Désirée). In the control treatment, soil water content was kept at field capacity over the whole growth cycle, while in the drought treatment water supply was restricted after tuber initiation (50 % of field capacity). Gas exchange and N content per unit leaf area (N_area) as well as ? were assessed at different stages. Sarnav showed the highest tuber yield in both water conditions, suggesting that yield in the water restriction treatment was largely driven by yield potential in this genotype. Higher stomatal conductance (g_s) and N_area and lower ?_leaflet in well‐watered Sarnav suggested higher photosynthetic capacity. Under water restriction, Sarnav maintained higher g_s indicating that carbon diffusion was a key factor for biomass accumulation under water restriction. Our results suggest the use of ? determined after tuber initiation as an indirect selection indicator for tuber yield under both well‐watered and restricted soil water availability conditions.  相似文献   

Erträge,n‐entzüge und humusdynamik im statischen düngungsversuch bad lauchstädt, 18 jahre nach erweiterung der versuchsfrage∗     

Martin Körschens 《Archives of Agronomy and Soil Science》2013,59(2):77-92

Im Statischen Düngungsversuch Bad Lauchstädt werden nach Erweiterung der Versuchsfrage seit 1978 die Prüffaktoren: Stalldung (2 Stufen), C_org‐Gehalt im Boden (6 Stufen) und Mineral‐N‐Mengen (5 Stufen) in der Fruchtfolge Kartoffeln, Winterweizen, Zuckerrüben, Sommergerste geprüft. Nur bei Sommergerste konnte eine Ertragswirkung des Stalldungs im Vergleich zu ausschließlicher Mineraldüngung nachgewiesen werden. Die jährlichen Veränderungen der C_org‐ und N_t‐Gehalte im Boden betrugen bei jeweils extremen Änderungen des Düngungsregimes bis zu 0, 012% C_org bzw. 0,0013% N_t.  相似文献   

Analysis of NO3 interception of the parasitic angiosperm Orobanche spp. using a positron-emitting tracer imaging system and 13NO− 3: A new method for the visualization and quantitative analysis of the NO3 interception ratio     

《Soil Science and Plant Nutrition》2013,59(3):408-416

Abstract

The root parasitic plants Orobanche spp. (broomrapes) seriously affect agricultural production. A visualization and quantitative analytical method for the interception of nutrients was established using a positron-emitting tracer imaging system and ¹³NO^? ₃. By using this analytical method that involves volume normalization with ¹⁸F^? images, the nitrogen nutrient interception ratio of the Orobanche spp. was calculated to be 73.6 ± 3.9% in a host–parasite system of red clover (Trifolium pratense L.).  相似文献