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月壤及模拟月壤微观结构的研究  [PDF]
李丽华,唐辉明,刘数华
岩土力学 , 2012,
Abstract: 为了对比研究月壤与模拟月壤的微观结构,介绍了月壤的形成作用过程和5种基本颗粒类型;通过真实月壤照片,对月壤微观结构进行了分析;利用火山灰为模拟月壤主体材料,对其成分进行了检测;对模拟月壤的火山灰颗粒进行了显微图像分析试验。结果表明,月壤存在胶结物微观颗粒,胶结物颗粒具有分支的组织形态和封闭的气泡,并且有金属铁珠存在;火山灰所含的主要成分及含量与月壤相似,经过粉碎的火山灰试样棱角较为明显,其纵横比峰值略小,稍显长条状,但与月壤比较相近,而复杂度因子则略有欠缺,说明颗粒还不够粗糙和多棱
模拟月壤研制的初步设想  [PDF]
郑永春,王世杰,刘建忠,李泳泉,邹永廖
空间科学学报 , 2005,
Abstract: 模拟月壤是月球样品的地球化学复制品.作者总结世界上已有的5种模拟月壤JSC-1,MLS-1,MLS-2,MKS-1和FJS-1的研制过程、方法与基本理化性质.认为系列化模拟月壤研制对中国首次月球探测有重要意义.在此基础上,作者提出系列化模拟月壤研制的基本思路.
钻进取样试验用模拟月壤  [PDF]
殷参
地质与勘探 , 2012,
Abstract: 钻具在月壤中进行钻进取样,是一个钻具与月壤相互作用的过程。为获得可靠的月壤钻具,在其研制过程中应在月壤里进行钻进试验。但地球上的真实月壤很珍贵,难以满足钻进试验的需要。采用能够较好地模拟真实月壤主要物理力学特性的模拟月壤,代替真实月壤进行钻进取样试验,是月壤钻具研制的一个必要手段。国外已对月壤进行了大量的研究,并取得了丰富的成果。本文在对真实月壤以及模拟月壤研究进行总结的基础上,对月壤钻具研制中所需的模拟月壤进行了简要的阐述,可供月壤钻具研制参考。
模拟酸雨对杂交稻常规稻野生稻影响的研究  [PDF]
农业环境科学学报 , 2004,
Abstract: 采用与研究区自然降雨的离子组成相近的不同pH值模拟酸雨,在营养生长期对栽植于试验小区的杂交稻、常规稻和野生稻进行了喷淋试验。结果表明,经不同浓度的酸雨喷淋后,杂交稻、常规稻和野生稻的叶片叶绿素含量、叶片相对电导率和产量性状等均发生了改变。pH值大于或等于3.5的酸雨对杂交稻、常规稻和野生稻的叶片叶绿素含量、叶片相对电导率和产量性状没有显著影响;pH值小于3.5的酸雨对杂交稻、常规稻和野生稻的叶片叶绿素含量、叶片相对电导率和产量性状的影响达到显著或极显著水平。其中酸雨对各生态型稻种细胞膜透性的影响程度为常规稻>野生稻>杂交稻;对叶绿素含量影响程度为杂交稻>常规稻>野生稻;对经济产量的影响程度为常规稻>杂交稻。
枯草芽孢杆菌和空心菜对鳝虾稻共作池塘水质的影响  [PDF]
邵乃麟,郭印,沈竑,陈金民,魏华
上海海洋大学学报 , 2016, DOI: 10.12024/jsou.20150501428
Abstract: 在黄鳝-克氏原螯虾-水稻共作塘中,进行了枯草芽孢杆菌和空心菜改善水质的对比实验。结果表明:枯草芽孢杆菌和空心菜对鳝虾稻共作水体均有较好的净化作用,能提升溶解氧、降低pH。其中,枯草芽孢杆菌处理对氨氮、亚硝酸氮、总氮、总磷的去除效果强于3种密度的空心菜,最高去除率分别达到68.06%、86.49%、49.96%和58.82%;单一投放空心菜时,以20%的密度处理对氨氮、亚硝酸氮、总氮、总磷的去除作用最强,最高去除率分别达到63.00%、88.39%、53.12%和49.02%。综上,鳝虾稻共作池塘搭配枯草芽孢杆菌和20%密度的空心菜为宜。
The contrast experiment was carried out about the effects of Bacillus subtilis and spinach(Ipomoea aquatica Forsk) on the water quality improvement in the pond during the co-farming of rice-crayfish-finless eel. The results showed that Bacillus subtilis and spinach both improved water quality, increased DO and decreased pH of water.Bacillus subtilis had better effects in the decreasing of the NH4+-N, NO2--N, TN, TP than spinach of three density groups with the highest level of degradation rate by 68.06%, 86.49%, 49.96%, and 58.82% respectively. Generally, the spinach with 20% of density degraded the level of NH4+-N, NO2--N, TN, TP by 63.00%, 88.39%, 53.12 and 49.02% most efficiently. In sum, the combination of Bacillus subtilis and spinach with the 20% density in the pond during the co-farming of the rice-crayfish-finless eel was better.
tj-1模拟月壤的研制  [PDF]
蒋明镜,李立青
岩石工程学报 , 2011,
Abstract: 以吉林省靖宇县境内的红色火山灰为原材料,将其烘干、粉碎、筛分后通过调整级配,力学试验成功研制出了tongji-1(简称tj-1)模拟月壤。测试了tj-1模拟月壤的矿物成分、颗粒形态、比重、内摩擦角、黏聚力、压缩指数、动剪模量、阻尼比及吸湿性能等,并将tj-1模拟月壤与月壤以及国际上已有模拟月壤的物理力学特性进行了对比分析。结果表明:tj-1模拟月壤的物理力学特性在月壤的范围之内,可模拟月壤的基本力学特性;且与其他模拟月壤相比,具有级配稳定,较大孔隙比时抗剪强度高的特点。
基于月壤物理力学特性的单齿破壤机理  [PDF]
周 琴, 刘宝林, 殷 参, 贾闵涛
地质科技情报 , 2014,
Abstract: 单齿破壤机理的研究是太空取样钻头研发非常重要和迫切的任务,是实现中国三期探月工程的月表钻进取样要求的重要研发基础。分析了反映月壤物理力学特性的主要参数及其之间的相关性及变化趋势,初步确定了2.5m深度内月壤物理力学的参数范围;基于月壤物理力学特性和月表钻进的钻进工艺分析,得出表层钻进和浅层钻进时月壤的破坏形式不同于土的掘削失效模型,主要是回转剪切破坏;提出了土的回转剪切力学模型,推导回转切削土阻力矩公式;得出阻力矩主要与钻头直径和切削刃宽度、月壤的容重和钻进深度等相关,并对其相关性进行了分析说明。
三层月壤模型的多通道微波辐射模拟与月壤厚度的反演  [PDF]
法文哲,金亚秋
空间科学学报 , 2007,
Abstract: 由月球表面数字高程试验性地构造了整个月球表面月壤厚度的分布.根据Clementine探月卫星的紫外-可见光光学数据,计算了整个月球表面月壤中FeO+TiO2含量分布,给出了整个月球表面月壤介电常数分布.由月球表层温度的观测结果以及月壤的导热特性,给出了月尘层与月壤层温度随纬度分布的经验公式.在这些条件的基础上,建立了月尘、月壤、月岩三层微波热辐射模型.由起伏逸散定理,模拟计算了该月球模型多通道辐射亮度温度.然后,以此辐射亮度温度模拟加随机噪声为理论观测值,按三层模型提出了月壤层厚度反演方法.由于高频通道穿透深度小,由高频通道的辐射亮度温度按照两层月尘-月壤微波热辐射模型反演月尘层与月壤层的物理温度,再由穿透深度较大的低频通道辐射亮度温度反演月壤层厚度.对于反演的相对误差也进行了讨论.
云南野生稻和地方稻资源抗白叶枯病分析
Identification of Yunnan wild rice and local landraces resistance ability to Xanthomonas oryzae pv. oryzae
 [PDF]

余腾琼,肖素勤,殷富有,张敦宇,李娥贤,程在全,Yu Tengqiong,Xiao Suqin,Yin Fuyou,Zhang Dunyu,Li Exian,Cheng Zaiquan
- , 2016, DOI: 10.13802/j.cnki.zwbhxb.2016.05.010
Abstract: 为鉴定云南稻种质资源对水稻白叶枯病的抗性情况,于孕穗期采用剪叶接种方法,用水稻白叶枯病强致病型代表菌株BD8438、CN9404和X1接种云南野生稻和地方稻种质资源,以病斑长度大于6 cm为感病分界线,对其抗感表现型进行调查分析。结果显示,共鉴定出来源于云南省不同种植生态区的186份地方稻抗性材料和22个野生稻抗病居群。野生稻对水稻白叶枯病的抗病能力较地方稻强,其中疣粒野生稻的抗性最强,抗病等级为0~2;药用野生稻次之,抗病等级为1~2;普通野生稻相对较差,抗病等级为1~5。地方稻抗性资源来自于云南省各个传统水稻种植区,抗性1级的材料占17%,抗性2级的占2%,抗性3级的占81%;按照稻种质资源亚种类型、粘糯性和水旱性分类,各类型地方稻抗性材料所占比例分别为粳稻占61%、籼稻占39%;粘稻占66%、糯稻占34%;水稻占83%、陆稻占17%。从利用抗白叶枯病基因培育新品种的角度评价,这些抗性资源具有潜在的发掘利用价值。
Bacterial blight, caused by Xanthomonas oryzae pv. oryzae (Xoo), is the most destructive bacterial disease of rice worldwide. In order to explore and utilize resistant cultivars to control bacterial blight, the wild rice species and local landraces of Oryza sativa L. were identified by using leaf cutting inoculation at booting stage in Yunnan, China. Three strong pathogenic strains BD8438, CN9404 and X1 of Xoo were used to screen wild rice and local landraces accessions collected from different areas of Yunnan. The susceptible boundary as the lesion length was greater than 6 cm. The results showed that 186 local landrace accessions and 22 wild rice native populations had different resistance abilities. The disease resistance of wild rice was stronger than the local landrace accessions. O. granulata had the strongest resistance (the grade of disease resistance was 0-2), O. officinalis had the second resistance (the grade of disease resistance was 1-2), O. rufipogon had the third resistance (the grade of disease resistance was 1-5). The local landrace rice resistant resources were collected from almost every traditional rice cultivation area in Yunnan, grade 1 accounted for 17%, grade 2 accounted for 2% and grade 3 accounted for 81%. These belonged to different types of O. sativa in terms of taxonomy-japonica rice and indica rice, or glutinous rice and non-glutinous rice, or upland rice and paddy rice. The japonica rice had more accessions (61%) with bacterial blight resistance ability than indica rice (39%), non-glutinous rice (66%) than glutinous rice (34%), paddy rice (83%) than upland rice (17%). These resistant resources had potential value to explore new varieties of resistance to bacterial blight.
西南稻区水稻产量的时空变化  [PDF]
张晓梅,丁艳锋,张巫军,吴晓然,李刚华
- , 2015, DOI: 10.3785/j.issn.1008-9209.2015.05.292
Abstract: 以西南稻区三省一市水稻生产数据为基础,分析了1978—2013年该区水稻产量时空变化特征及其主要影响因素。结果表明:1978—2013年西南稻区水稻总产增加了40.0%,其中,1980s—1990s水稻总产增幅较大,1990年后在波动中趋于稳定;水稻种植面积呈“波浪式”下降,降幅达11.0%,其中,种植面积以四川为主,达45%以上,云南种植面积及占西南稻区的比值稳中有升;1980s—1990s水稻单产大幅增加是总产增加的主要驱动因子,但单产平均水平仍低于7 000 kg/hm2;气候变化不利于水稻单产提高,以四川、云南表现最为明显。稳定云南水稻种植面积,遏制四川、贵州和重庆水稻种植面积下降趋势是促进西南水稻总产增加的基本条件;通过高产抗逆品种选育、高产栽培结合防灾减灾新技术充分挖掘水稻单产潜力,提高云南和四川水稻单产水平,是西南稻区水稻总产稳定增加的主要途径。
Abstract: In order to reveal spatial and temporal variation and related influencing factors of rice yield in Southwest China, the rice production data were analyzed in four administrative regions including Yunnan, Guizhou, Sichuan and Chongqing during 1978—2013 years. The results showed that the rice production increased by 40.0% during 1978—2013 years in Southwest China, with the higher increase during 1980s—1990s and keeping relatively stable after 1990. Meanwhile, rice planting area was reduced by 11.0%, which indicated an adverse condition that may restrict sustainable rice production. Rice planting area in Sichuan accounted for more than 45% in Southwest China and rice planting area in Yunnan showed increasing trend since 2000, which was the basic condition that ensured large increase in rice production during 1980s—1990s. Rice yield improvement was a key factor to promote higher rice production; however, the rice yield was still lower than 7 000 kg/hm2. Climate change posed an adverse effect on higher rice yield in this stage, particularly in Sichuan and Yunnan. Taken together, basic measures should be carried out to ensure the sustainable rice production such as inhibiting planting area reduction in Sichuan, Guizhou and Chongqing, keeping steady increase in Yunnan. In addition, major ways should be taken to breed high-yielding varieties with stress resistance, to create new cultivation techniques in combination with prevention and reduction of natural disasters in rice production, particularly in Sichuan and Yunnan.
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