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1.
针对温室大棚内空间复杂、不便铺设有线线路的实际情况,设计采用当前较流行的无线Zigbee技术的温、湿度监控系统。在设计的系统中将多个Zigbee节点放置在温室大棚的适当位置,形成无线自组织网络,节点上的温度、湿度传感器负责采集环境信息,通过有线的以太网或无线的GSM、GPRS、CDMA等网络进一步传送给监控中心的计算机进行分析处理,将棚内的温度、湿度参数控制在适宜作物生长的范围内,提高经济效益。  相似文献   

2.
通过对塑料大棚内温度、湿度、光照、气体等小气候条件和棚内土壤等栽培环境的分析研究,提出适合信阳市秋冬季节塑料大棚小气候的调控方法,旨在为秋冬蔬菜的生长提供一个适宜的环境条件。  相似文献   

3.
土壤有机质含量是影响CH4产生的最重要土壤性质。土壤CH4氧化能力与包括活性碳、有机碳和全氮含量在内的土壤理化性质之间都不存在显著相关性。非水稻生长期较高的水分含量能促进水稻生长季节CH4的产生、氧化和排放。在影响稻田CH4排放大尺度空间变异性的主要因素中,土壤水分历史可能比土壤性质更为重要。结果表明,非水稻生长期土壤水分对水稻生长期CH4产生、氧化和排放具有极其重要的控制和调节作用。  相似文献   

4.
为解决花卉在没人看管的情况下也能实现自给补水,设计了多路自动浇灌系统。该系统采用Labview为上位机,Arduino为下位机相结合的控制模式。系统运行时,土壤湿度传感器先对盆栽土壤进行参数采集,再经Arduino对采集数据信号进行分析判别,若盆栽需要浇灌,舵机将带动浇灌臂在盆栽的指定位置进行浇灌,直至湿度达到标准值,最后将浇灌后的湿度值通过蓝牙传输至labview上位机显示。本系统先后经过模拟仿真和实地检测等测试,测试结果达到预期设计要求,系统运行稳定。  相似文献   

5.
剥制标本多为国家保护动物剥制而成,且易受外界环境侵害,如潮湿、日光照射、虫害等。故平时如管理不善,极易受损。管理好剥制标本有以下简易方法:首先管理好保存的环境,控制霉菌生长。霉菌生长离不开水分,当空气湿度在70%以上时,霉菌易生长繁殖,出现霉斑,长期处在这样的环境中,  相似文献   

6.
盐碱化土壤限制植物的正常生长,明确禾本科草本植物对NaHCO3和Na2CO3胁迫的适应机制对于盐碱土壤的开发利用以及作物的种植具有重要意义。以碱茅和披碱草为材料,用NaHCO3和Na2CO3混合物胁迫处理,测定碱茅和披碱草的种子发芽率、幼苗干重、叶片细胞膜透性、光合气体交换参数、叶绿素荧光参数、叶片超氧化物歧化酶活性和丙二醛含量,以及叶片和根系Na+、K+离子含量。结果显示,胁迫处理降低碱茅和披碱草种子发芽率、幼苗干物质积累、叶片净光合速率和电子传递量子效率,并提高两种植物相对电导率和丙二醛含量。胁迫处理下碱茅叶片质膜的受损程度大于披碱草,叶片光合气体交换参数受影响更大,而披碱草更能维持SOD酶活性,相同混合物浓度处理时其叶片MDA含量低于碱茅。综上,NaHCO3和Na2CO3混合处理抑制碱茅和披碱草的正常生长,但披碱草的抗逆性强于碱茅。本研究通过生理特性分析筛选出潜在的更具耐盐碱材料,能够为盐碱地区土壤的生物修复以及禾本科作物的种植提供理论依据。  相似文献   

7.
通过对陕西南部大巴山地区的基岩、土壤、作物、泉水及地表水中含碘量和分布规律的研究,发现本区环境中碘的分布很不均衡,变化较大,包括从极低碘到高碘的多种情况.本区主要分布的早古生代地层均富碘,岩石的含碘量为 0.7~ 1.9mg/kg.在山坡坡度较缓的基性火成岩分布区的基岩、土壤、作物均富碘,一般为 1.4~ 0.9mg/kg.土壤的含碘量为 0.2~ 2.2mg/kg ;土豆的含碘量为 8~ 1 80 μg/kg.由于长期的风化剥蚀,大巴山区大多数地区的土壤和作物缺碘,特别是碳酸盐岩分布区以及高大山头上部的土壤和作物均缺碘.土壤和作物中含碘量与其分布区的基岩的岩性和含碘量以及地理环境密切相关,同时本区克汀病的分布和发病率与环境中碘的含量和分布也密切相关.  相似文献   

8.
硼肥在作物中的作用和施用方法   总被引:1,自引:0,他引:1  
硼素在作物体内有重要的生理作用。我市土壤有效硼平均含量较低,合理施用硼微肥有利于提高作物的产量和品质。  相似文献   

9.
土壤呼吸是全球碳循环中的一个重要环节,其对全球碳平衡的影响是近年来人们关注的焦点之一。土壤呼吸主要受到温度、湿度、有机碳等环境因素的作用,并且随着人类影响的增强,人为因素的作用也越来越大。本文讨论了影响土壤呼吸的主要影响因素及其相互关系。  相似文献   

10.
通过开展造林密度、土壤施肥、林农间作等试验,进行平原杨树纤维用材林优化培育技术研究。结果表明,密度控制、土壤施肥、林农间作等措施不仅能提高林木生长量,改善林地土壤及树体营养状况,还能增加额外效益,是提高造纸用材林木材产量和经济效益的有效技术措施。  相似文献   

11.
Since the late 1960s,culture has been considered tighter with communication.Culture IS based on the community of communication.Communication involves people and their environment.Thus culture is an important factor in communication.Today with modem economic and technological development,intercultural communication is mole important than ever before. When people from different cultural background communicate with each other,their social stereotype pattern of behavior, their habits of language and thought differ from one another,because these are the possible factors that affect intercultural communications.Culture norms also change,culture may be transferred as signs but we have to study and understand the above carefially.  相似文献   

12.
The article introduces Shakespeare's tragedy "Hamlet".Hamlet wants to revenge for his father.But when the opportunity is coming,he delays his revenge.The passage analyzes the causes of his delay from Hamlet's characters.  相似文献   

13.
The thesis mainly discusses the character of the heroine in Charlotte Brontes famous novel "Jane Eyre". There are three major parts-introduction,analysis which is the main body of the thesis,and conclusion.Jane Eyre,the heroine,is a new woman image who requires independence equality and freedom.The thesis just analyzes Janes these rebellious characters through four peroods of her experiences.First,in her childhood,she has shown her rebellious spirit.As an orphan,Jane suffers a lot of misery.Not only her aunt treats her cruelly,her cousins despise her,but also do servants have a prejudice against her.In Janes immature heart, she is unwilling to bear ill treatment.She rebels them bravely.Second,when she studies at Lowood,her rebellious spirit is exposed furtherly.Her view doest stay in Mrs Reeds,instead turns to the whole society.She makes hypocrisy of so-called charity to be discovered completely.At the same time,she declares her independent,equal rebellious thought to her friend-Helldn who endures oppression willingly.Third,she,as a governess in Thornfield Hall falls in love with Rochester-her master.During this period,her thought grows into maturity.Thought she loves him passionately,she never loses her dignity and independence for him.When she knows his mad wife still lives,she makes up her mind to leave him.For she doesnt want to become his mistress.Fourth,her refusal of St Johns proposal of marriage depicts Janes character.She knows John does not love her at all and his purpose of marriage is only to perform his great task missionary.Jane does want to become a sacrifice.She breaks traditional morality,then she goes back to Rochester.  相似文献   

14.
The context of a word consists of the other words surrounding it and the situation in which it is used.When we come across a new word in our reading,instead of looking it up in a dictionary for its definition,we can guess its meaning from its context.  相似文献   

15.
Introduction Whatisculture?Toputitsimply,culturemeansthe totalwayoflifeofaperson.Thissimpledefinitionimplies thatculturereferstothepattersofcustoms,traditions,socialhabits,values,beliefsandlanguageofasociety.As cultureissoinclusive,itincludesvirtuallyeverythingthat agroupofpeoplethink,say,doandmake.Followingthedefinitionofsociologists,theterm culturereferstothetotalpatternofbeliefs,customs,institutions,objects,andcharacterizesthelifeofhuman community.“Cultureconsistsofallthesharedproductsof …  相似文献   

16.
当代中国武术经历了时代的沧桑和变迁,在历经了文化和历史的发展与洗礼之后,依然发展、繁衍至今。在这样一个漫长的过程中,伴随着以社会环境和社会人群价值取向为主的变迁与变化,当代中国武术的发展与当代社会的发展正逐渐的呈现出某些相背离和不和谐的表象。通过研究,我们发觉中国武术中原本一些内在的东西正在不断的被遗忘,正在不断的流逝。本文试从中国武术在当代发展中的问题境域入手,解读中国武术在当今世界和社会中存在的一些问题,希望能够从中找到中国武术发展的"合法性"或"合时性"的内在依据,以挺立中国武术的脊梁。  相似文献   

17.
"Midnight"is a poem written by Archibald·Lampman,a Canadian poet,who loved nature very much,but his poor health prevents him from being very active in the outdoor life.So he is often the quite,thoughtful observer of nature in his poems.This article mainly talks about how to appreciate the poem in the following aspects:word selecting,rhyme,sentence structure and atmosphere.After reading this poem,we cannot get rid of the air of horror and mystery."Midnight" reveals another aspect of the nature:wild,rough and unknown.There is something else in the nature that can awe human beings even though we don't know what it is.  相似文献   

18.
Chapter Ⅰ Introduction Sitting in the rocking chair,Carrie dreams her future.This is the deep impression the novel"Sister Carrie"gives us,which is written by Theodore Dreiser(1871-1945),the great American realism writer.  相似文献   

19.
运用临场观察统计法、访谈法、文献资料法以及归纳法等研究方法,对现阶段国内青少年足球守门员防守技术运用情况进行统计与分析研究.结果表明:判断反应与选位能力不足是青少年守门员防守技术失误的主要原因,预判失误与技术粗糙以及缺乏自信等导致青少年守门员对抗条件下难以有效发挥位置优势,强干扰情况时出击争夺球失误多,重视反应训练和提高接球动作质量要求是提高青少年守门员技术水平的重中之重.  相似文献   

20.
提高体校学生的语素质的主要途径是课堂教学。体校语教师在教学过程中必须根据学生身心特点.设置合理的结构模式,以便顺利实现教学目标。  相似文献   

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