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NaCl胁迫下高羊茅生长及K+、Na+吸收与运输的动态变化 总被引：7，自引：12，他引：7
通过室内水培试验研究探讨了NaCl胁迫对高羊茅苗期生长及K 、Na 吸收与运输的影响及其随时间的变化.结果表明,高羊茅苗期的干物质重和分蘖数随盐分水平的升高而降低,且与NaCl浓度存在极显著的负相关关系(r=-0.990 2**);NaCl胁迫对高羊茅苗期茎叶生长的抑制作用大于对根系的影响;NaCl盐浓度的增加使高羊茅地上部干物质重、K 的相对含量、K / Na 、S K / Na 吸收降低,Na 的相对含量增高;胁迫时间对K 、Na 含量的影响显著.高羊茅根系对K 的吸收具有较高的选择性,吸收选择性系数S K / Na 吸收主要受环境盐分浓度的影响,但运输选择性系数S K / Na 运输却主要受胁迫时间的影响,且盐分阈值随胁迫和生长时间的增加而呈下降趋势. 相似文献
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Recently,distributed intelligent systems based on multi-agent have been applied to many fields successfully.the multi-agent technique is introduced into the rotating machinery fault diagnosis system.With the combination of CBR technique,Basalstructure and development approach of the system are analyzed,and better cooperation among agents is realized.As a result,the system overcomes the limitation of single fault diagnosis method,and solves the contradictionbetween versatilityand adaptabilityof diagnosis software.Furthermore,a reference can be used for the research and development of multi-algorithmdiagnosis system of rotating machinery.The application in a factory's Networked Online Monitoring and Fault Diagnosis System for Turbine Fan shows that the system can diagnosefault rapidly and exactly. 相似文献
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Influence of one macromolecule-type retarder bone glue on the setting time, strength, ion concentration in liquid phase and supersaturation degree, crystal morphology of dehydrate and microstructure of hardened paste of building gypsum is investigated. Furthermore, internal cause of strength loss of building gypsum with addition of retarder is analyzed, The results indicate that bone glue could retard the hydration of building gypsum markedly, but its negative influence on the strength of building gypsum is far lower than that of low molecule-type retarders. Bone glue has a minor effect on crystal morphology of dehydrate and porosity of hardened paste, but it causes the large crystal size and coarsening of pore size distribution of hardened gypsum paste, which is the very intrinsic reason of strength loss of building gypsum. 相似文献
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Based on model parameters estimating, a kind of algorithm of pole-zero placement self-adaptive temperature control is put forward according to closed loop apices distribution of resistance furnace temperature control. The mathematic model is presented by discursion for the controlled object, at the same time, the algorithm is illustrated identification method of model parameters, compute formula and simulation result of controlled parameters. Simulations and practices of the model proved that the algorithm is of rapid constringency speed , satisfactory effect on the object with time changing especially for the controlled objects of the high current and low voltage characteristics. The algorithm has been applied in the temperature control of intelligent slag measurement equipment of a iron-steel graduate school. 相似文献
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本文主要介绍马蔺在盐胁迫下的生长状况以及K 、Na 含量和分布情况。采用砂培试验对马蔺的耐盐性进行了研究。试验结果表明在NaCl胁迫下,随着胁迫浓度的增加,马蔺生物量、株高、干重、肉质化以及K 含量、K /Na 比值降低,同时根冠比、Na 含量增加;各盐处理区根系含水量和肉质化程度大于茎叶,但与盐浓度的相关性不大。在土壤盐浓度<20.0g/kg时,盐胁迫使马蔺根系K-Na的选择性吸收降低,但却增强了向茎叶中运输K 的能力。马蔺受NaCl胁迫时,生长受抑制与植物组织内Na 含量提高和K /Na 比值的降低有关。 相似文献
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【目的】探讨施用硝态氮对马蔺(Iris lactea Pall. var. chinensis(Fisch.)Koidz.)耐盐性及叶片渗透调节物质的影响,为马蔺的栽培和管理提供理论依据。【方法】采用砂培马蔺幼苗,透灌含不同浓度NaCl和硝态氮的营养液(设置3个NaCl浓度0.1、140、210 mmol•L-1与3种硝态氮含量0.25、4和8 mmol•L-1交互组合的9个处理),处理35 d后,测定叶片和根部的生物量、矿质元素吸收量以及叶片中主要渗透调节物质的含量。【结果】在中等盐浓度(140 mmol•L-1)处理下,施加多量硝态氮(8 mmol•L-1)更大程度地促进了马蔺叶片生物量的累积。当NaCl浓度增高到210 mmol•L-1时,4 mmol•L-1和8 mmol•L-1硝态氮处理区的叶片生物量相比对照增加了约30%,但两种浓度的效果没有显著差异(P＜0.05)。施加硝态氮降低了NaCl胁迫下马蔺的根冠比和叶片质膜透性,提高了叶片和根部的氮素含量,但没有显著改变无机离子(K+、Na+、Ca2+、Mg2+)的吸收量。硝态氮和NaCl交互组合处理下,叶片渗透调节物质中各无机离子的浓度大小为：Cl-＞K+＞Na+＞NO3-。硝态氮的施加显著降低了Cl-、Na+和K+浓度,但提高了脯氨酸和NO3-浓度。【结论】外施适量的硝态氮能显著提高马蔺的耐盐性,其机理与盐胁迫下氮营养的改善、脯氨酸和NO3-含量的增加以及根冠比、Cl-和Na+含量的降低等有关。 相似文献
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以STC89C52单片机作为核心控制器,基本定时开关功能通过DS12CR887时钟芯片提供的时间标准与设定时间的比较结果控制继电器来实现开启和关断用电器,遥控功能通过SC2272解码芯片无线遥控来实现电器的开关,按键可以对实时时间,定时时间,模式选择等进行设置,开关由继电器控制交流电的开关,LCD1602显示相关定时信息和模式。从而保证了电器在各种场合下都可以不过度浪费电,也解决了人不在时的麻烦。 相似文献
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受精液中添加β-ME、BSA和咖啡因对猪卵母细胞体外受精后早期发育的影响 总被引：5，自引：0，他引：5
进行受精液中添加不同浓度的β-ME、BSA和咖啡因对猪卵母细胞体外受精及其早期发育的影响试验。结果表明,在受精液中添加β-ME(2、10、50μmol/L)对猪卵母细胞体外受精后的早期发育无显著促进作用,当添加浓度过高(250μmol/L)时对早期胚胎发育反而不利;在受精液中添加咖啡因(1、2、4mmol/L)对猪卵母细胞体外受精后的早期发育无显著的促进作用;在受精液中添加BSA(0.1%、0.2%、0.4%、0.8%)对猪卵母细胞体外受精后的早期发育有一定的促进作用,并以添加0.4%BSA的效果最好。 相似文献
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In accordance with the requirements of industrial mechanical vibration field data real-time transmission in the condition of multi-survey-point and mass data acquisition, an Ethernet data transmission method based on Ethernet controller RTL8019AS and TMS320C5402 DSP is presented. Packing data from A/D into UDP and IP package and controlling RTL8019AS through I/O mapped registers, high-speed DSP makes real-time communication high performance. Ethernet frame protocol and TCP/IP protocol are simplified for the specific purpose. And the interface technology between Ethernet controller RTL8019AS and DSP is solved. The system evaluation and debugging are made. 相似文献