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Effects of Nitrogen Fertilizer Management on Biological Traits and Physiological Indexes at Seedling Stage and Yield of Directly-sown Rapeseed(Brassica napus L.) 被引量:1
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作者 杨云飞 刘士山 吴永成 《Agricultural Science & Technology》 CAS 2017年第12期2401-2405,2414,共6页
Field experiments were carried out to study the effects of different nitroge- napplication rates and application times on biological traits and physiological indexes of directly-sown rapeseed (Brassica napus L.) at ... Field experiments were carried out to study the effects of different nitroge- napplication rates and application times on biological traits and physiological indexes of directly-sown rapeseed (Brassica napus L.) at the seedling stage and investigate the relationship between these biological traits or physiological indexes at the seedling stage and yield, so as to provide scientific theoretical support for high yield and efficient fertilization management in production of winter rapeseed. Field trials were conducted in Chengdu plain of Sichuan Province under rice-rapeseed rotation system during the period of 2011-2012. The nitrogen application rate trial consisted of five nitrogen levels (0, 90, 180, 270 and 360 kg/hm2) and the nitrogen application time trial included NTl(single application as base fertilized), NT2 (bottom application +one time of topdressing at seedling stage) and NT3 (bottom application+two times of topdressing at seedling stage) under the same nitrogen rate (225 kg/hm2). The results indicated that compared with no nitrogen application (NO) treatment, the in- crease of nitrogen fertilizer is beneficial to the increase of biological traits including plant height, green leaf number, leaf area index and dry weight of rapeseed at the seedling stage, the improvement of physiological indexes including total nitrogen content, chlorophyll content and soluble protein content of functional leaves, and the reduction of soluble sugar content. Nitrogen rate was linearly correlated with various biological traits at the seedling stage and physiological indexes including total nitro- gen content, chlorophyll content and soluble sugar content in functional leaves over- a/I, but in parabolic correlation with soluble protein content. Under the same nitrogen rate, NT2 treatment exhibited biological traits remarkably or significantly higher than NT1 treatment and NT3 treatment. The nitrogen application times were linearly cor- related with the physiological indexes of functional leaves at the seedling stage. The various biological traits and physiological index of functional leaves at the seedlings stage were in quadratic function parabolic correlation with seed yield, and the corre- lation was significant (P〈0.05). Therefore, under the rice-rapeseed rotation system in Chengdu plain, the economic rational nitrogen rate is 180-225 kg/hm2, and the mode of bottom application + one time of topdressing (NT2) is suitable. 展开更多
关键词 Winter rapeseed (Brassica napus L.) Direct seeding Nitrogen fertilizermanaaement Bioloqical traits Physioloqical index YIELD
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新技术与成果
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《中国金属通报》 2000年第12期16-16,共1页
锥形/回转破碎机中的高破碎比破碎机构在锥形/回转破碎机破碎腔中,材料的驻留时间是通过破碎机在破碎表面下端处设置流动约束机构来控制的。流动约束机构包括在套的下端处配置的朝外的指状环圈,突缘或锥台。这些指状物与配置在筒衬下端... 锥形/回转破碎机中的高破碎比破碎机构在锥形/回转破碎机破碎腔中,材料的驻留时间是通过破碎机在破碎表面下端处设置流动约束机构来控制的。流动约束机构包括在套的下端处配置的朝外的指状环圈,突缘或锥台。这些指状物与配置在筒衬下端处的朝内的指状物相互交叉。流动约束机构也可包括一个配置在套下端的固体环或锥台。(CN1194885A) 展开更多
关键词 约束机构 制造方法 变形量 回转破碎机 新技术 指状物 破碎机构 驻留时间 破碎比 破碎腔
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蚀雕可挠性电路
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作者 N.Kirby 孔祥林 《印制电路信息》 1999年第1期41-43,46,共4页
蚀雕挠性电路的优点可摘要叙述以下几点:a.电源承载能力b.紧固的延伸指状物c.坚固的元件连接点d.低成本的跨接线e.热控制f.能蚀刻任意的形状g.低成本的工具h.支掉分立的连接器i.提升触点(RCP'S) 除了上述的优点外,还具有通常挠性电路... 蚀雕挠性电路的优点可摘要叙述以下几点:a.电源承载能力b.紧固的延伸指状物c.坚固的元件连接点d.低成本的跨接线e.热控制f.能蚀刻任意的形状g.低成本的工具h.支掉分立的连接器i.提升触点(RCP'S) 除了上述的优点外,还具有通常挠性电路技术的所有优点。 展开更多
关键词 电路技术 可挠性 指状物 连接器 跨接线 印制电路板 低成本 热控制 连接点 绝缘材料
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Nutrients distribution and trophic status assessment in the northern Beibu Gulf, China 被引量:17
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作者 赖俊翔 姜发军 +3 位作者 柯珂 许铭本 雷富 陈波 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第5期1128-1144,共17页
Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore wat... Using historical and 2010 field data, the distribution of nutrients in the northern Beibu Gulf of China is described. There was a decreasing trend in the concentration of nutrients from the north coast to offshore waters of the northern Beibu Gulf, reflecting the influence of inputs from land-based sources. High concentrations of dissolved inorganic nitrogen (DIN) and phosphate (PO4-P) occurred mainly at Fangchenggang Bay, Qinzhou Bay, and Lianzhou Bay. Four different methods were used to assess eutrophication. The trophic status of the Beibu Gulf was characterized using the single factor, Eutrophication index (El), Trophic index (TRIX) and Assessment of Estuarine Trophic Status (ASSETS) methods. Based on nutrient concentrations, 73.9% of DIN and 26.7% of PO4-P samples exceeded the fourth grade Seawater Quality Standard of China. Eutrophication index values varied widely, but higher levels of eutrophication were generally found in bays and estuaries. TRIX values ranged from 2.61 to 7.27, with an average of 4.98, indicating a mesotrophic and moderately productive system. A positive correlation between TRIX and harmful algal species richness and abundance was observed. The ASSETS model evaluates eutrophication status based on a Pressure-State-Response approach, including three main indices: influencing factors, overall eutrophic condition, and future outlook. The Beibu Gulf was graded as moderate using ASSETS. The single factor and Chinese nutrient index methods were considered inadequate for the assessment of trophic status. TRIX can be used as an indicator of trophic state and ASSETS showed good potential to assess eutrophication. The results of TRIX and ASSETS depend on threshold values. To establish these values, further research is required within the northern Beibu Gulf. 展开更多
关键词 nutrient EUTROPHICATION Trophic index (TRIX) Assessment of Estuarine Trophic Status(ASSETS) Beibu Gulf Guangxi Province
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Effects of coal prices on merchandise prices in China 被引量:4
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作者 Ding Zhihua Zhou Meihua Liu Yan 《Mining Science and Technology》 EI CAS 2011年第5期651-654,共4页
Coal is the principal form of energy used in China. Hence, coal price variations are expected to have some influence on merchandise prices. Monthly data from January, 2002, to October, 2010, were used to construct a v... Coal is the principal form of energy used in China. Hence, coal price variations are expected to have some influence on merchandise prices. Monthly data from January, 2002, to October, 2010, were used to construct a varying-parameter state space model, and an error correction model, to estimate the influence of coat prices on Chinese merchandise prices. The time lag and the dynamic relationship were determined from the data. A long term equilibrium relationship between coal price and the PPI, and the CPI, can be observed. The long term influence of coal price fluctuations on the PPI is 0.263%. The corresponding value for the CPI is 0.157%. The PPI shows an influence from coal price change in the first period of observation: by eight periods the influence is obvious, after which it diminishes. The effect of coal price change on the CPI is rather weak and has no long term memory. Analysis of variance shows a similar situation. The elas- ticity coefficient of coal prices on the CPI, or the PPI, fluctuates over the 2002-2004 period. From 2002 to 2007 the influence elasticity on the CPI declined and subsequently levelled off after 2009. 展开更多
关键词 Coal priceState space modelMerchandise pricePrice fluctuation
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Phytoplankton community structure in reservoirs of different trophic status, Northeast China 被引量:10
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作者 马成学 于洪贤 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第3期471-481,共11页
The aim of this study was to determine the phytoplankton community structures of reservoirs of different trophic status, located in a cold region. Physical and chemical variables and the phytoplankton communities were... The aim of this study was to determine the phytoplankton community structures of reservoirs of different trophic status, located in a cold region. Physical and chemical variables and the phytoplankton communities were investigated in two reservoirs (Xiquanyan Reservoir and Taoshan Reservoir) in Northeast China in 2009. The two reservoirs showed strong seasonal fluctuations in their physical and chemical composition. Results of the trophic status index indicated that Xiaquanyan Reservoir was mesotrophic, whilst Taoshan Reservoir was eutrophic. Diatoms were the dominant phytoplankton group in Xiquanyan Reservoir throughout all seasons of the study, while in Taoshan Reservoir, diatoms dominated in spring, and cyanobacteria dominated in summer and autumn. This difference was resulted from differences in local environmental factors, including nutrients and hydrology. This study suggests that in mesotrophic reservoirs, nutrients played a key role in controlling seasonal phytoplankton successions, whereas in eutrophic reservoirs water temperature was the key factor in a cold region. Notably, the dominant species in summer in the Taoshan Reservoir was Microcystis, which may produce toxins depending on the ambient conditions, and presenting a risk of local toxin contamination. 展开更多
关键词 trophic status phytoplankton community RESERVOIR cold region
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Overexpressed BRH1, a RING finger gene, alters rosette leaf shape in Arabidopsis thaliana 被引量:9
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作者 Xiaoqian Wang Eryong Chen +6 位作者 Xiaoyang Ge Qian Gong HamamaIslam Butt Chaojun Zhang Zuoren Yang Fuguang Li Xueyan Zhang 《Science China(Life Sciences)》 SCIE CAS CSCD 2018年第1期79-87,共9页
Leaves are the most important plant parts for photosynthesis and respiration. Many genes are involved in determining leaf shape;however, little is known about the effects of brassinosteroid (BR) signaling-pathway gene... Leaves are the most important plant parts for photosynthesis and respiration. Many genes are involved in determining leaf shape;however, little is known about the effects of brassinosteroid (BR) signaling-pathway genes on the development of leaf shape. Here, the brassinosteroid-responsive RING-H2 (BRH1) gene, which is suppressed by 24-epi-brassinolide treatment, was isolated from Arabidopsis thaliana. The amino acid sequence contained a highly conserved RING finger domain. In a phylogenetic analysis,BRH1 clustered closely with GLYMA11G02470.1. The leaves of brh1 mutant plants were not much different to those of the wild-type, while transgenic plants with high BRH1 expression levels had rounder rosette leaves. Mutants of the BR synthesis pathway also had a similar round leaf phenotype, and greater BRH1 expression levels. Moreover, the related marker genes KNAT1,AtHB13 and ROT4, which are known to control leaf shape, altered transcriptional levels in both transgenic BRH1 and BR-synthesis mutant lines. Thus, BRH1 may be involved in the BR signaling pathway and regulate the growth and development of rosette leaves. Research on BRH1 may prove valuable for understanding the regulatory mechanism of leaf shape and improving the leaf shapes of ornamental plants. 展开更多
关键词 BRH1 RING finger leaf shape brassinosteroids
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A Fuzzy-based Methodology for an Aggregative Environmental Risk Assessment of Restored Soil 被引量:7
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作者 WANG Shi-Zhong ZHAO Zhi-Hao +3 位作者 XIA Bing QIU Hao J.L.MOREL QIU Rong-Liang 《Pedosphere》 SCIE CAS CSCD 2014年第2期220-231,共12页
Environmental risks pertaining to contaminated soils have been well studied,while little attention has been paid to the risks of the soils after remediation. In this study,a concept model developed based on fuzzy set ... Environmental risks pertaining to contaminated soils have been well studied,while little attention has been paid to the risks of the soils after remediation. In this study,a concept model developed based on fuzzy set theory was applied to evaluate the uncertainties of three risk indicators,namely,plant growth,groundwater safety and human health,of a restored site that had been previously polluted by heavy metals. The concept model classified the grade and importance of risk factors by an 11-level ranking system and was able to yield a comprehensive risk result rather than multi-risk results for complex risk indicators. Modeling results showed that the risks to the three indicators were effectively reduced after the remediation. Moreover,great sensitivity of the risks was found related to the weight distribution among the three risk indicators. In general,the risks of both polluted and restored soils to the environment were in the order of groundwater safety > plant growth > human health. The model was proved to solve the problems of multi-risk results due to complex risk indicators that previously encountered by other researchers,which made it helpful in decision-making and management of restored soils. 展开更多
关键词 fuzzy set theory heavy metals remediated risk assessment weight distribution
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Biological indicators of sub-optimal health status 被引量:1
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作者 Limin Wang Xin Zhao +5 位作者 Jiaxu Chen Xiaoling Guo Xin Liang Danhui Yi Huating Cui Yueyun Liu 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第5期647-650,共4页
OBJECTIVE:To investigate biological indicators of sub-optimal health status and provide means of objective assessment of sub-optimal health status.METHODS:We set the unified standards for diagnosing a SHS.We tested va... OBJECTIVE:To investigate biological indicators of sub-optimal health status and provide means of objective assessment of sub-optimal health status.METHODS:We set the unified standards for diagnosing a SHS.We tested various laboratory indicators in 407 cases that we selected randomly from2807 subjects and collected 15 mL of fasting venous blood from each case.We measured serum immunoglobulin A(IgA)and immunoglobulin G(IgG)concentrations,serum beta endorphins(β-EP),cortisol(C),testosterone(T),plasma adrenocorticotropic hormone(ACTH)and serum T lymphocyte subsets CD3+and CD4+.RESULTS:Mean serum testosterone concentrations and their ratio to cortisol(C)concentrations weresignificantly higher in the healthy group than in those with sub-optimal health status(P<0.01).Mean serum CD3+concentrations were significantly higher in those with sub-optimal health status than in the healthy group(P<0.05).CONCLUSION:Decreased serum testosterone/cortisol ratio may be an objective indication of sub-optimal health status.Changes in neuroendocrine and immunological indicators may explain some of the symptoms,including malaise and poor work performance,attributable to persistent or relapsing fatigue in subjects with sub-optimal health status. 展开更多
关键词 Testosterone Hydrocortisone Sub-optimal health status Biological indicator
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