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101.
研究了H2O2对陈化马铃薯切片抗氰呼吸的诱导作用.用切片和纯化线粒体进行测定的结果均表明外源H2O2(5.0 mmol/L)处理对陈化马铃薯切片的总呼吸只有微弱的影响,但却可以明显诱导切片的抗氰呼吸,并显著提高抗氰呼吸对总呼吸的贡献.应用交替氧化酶的单克隆抗体进行Western杂交的结果表明,H2O2处理可以增强陈化马铃薯切片中交替氧化酶的表达,表明H2O2对抗氰呼吸的诱导作用与其时交替氧化酶表达的诱导有关.抗氰呼吸可能参与了H2O2调控植物抗病防御反应的作用机制. 相似文献
102.
传统的插秧机分插机构的设计选用单一的机构,由于其性能的限制,在设计时只能根据秧爪运动轨迹,取秧与插秧角度来设计插秧机分插机构,但分插机构的设计还应该考虑在各关键位置及各工作段时秧爪尖的运动速度,只有同时考虑这两方面的需要,才能设计出性能良好的分插机构,文章采用空间RSSR机构与平面连杆机的组合机构来实现这一目的。 相似文献
103.
Mestdagh FJ De Meulenaer B Van Poucke C Detavernier C Cromphout C Van Peteghem C 《Journal of agricultural and food chemistry》2005,53(15):6170-6174
Acrylamide formation was studied by use of a new heating methodology, based on a closed stainless steel tubular reactor. Different artificial potato powder mixtures were homogenized and subsequently heated in the reactor. This procedure was first tested for its repeatability. By use of this experimental setup, it was possible to study the acrylamide formation mechanism in the different mixtures, eliminating some variable physical and chemical factors during the frying process, such as heat flux and water evaporation from and oil ingress into the food. As a first application of this optimized heating concept, the influence on acrylamide formation of the type of deep-frying oil was investigated. The results obtained from the experiments with the tubular reactor were compared with standardized French fry preparation tests. In both cases, no significant difference in acrylamide formation could be found between the various heating oils applied. Consequently, the origin of the deep-frying vegetable oils did not seem to affect the acrylamide formation in potatoes during frying. Surprisingly however, when artificial mixtures did not contain vegetable oil, significantly lower concentrations of acrylamide were detected, compared to oil-containing mixtures. 相似文献
104.
栗疫病菌对板栗几丁质酶活性的诱导 总被引:1,自引:0,他引:1
以板栗 (Castanea mollissima Bl.)实生苗和嫁接苗 (怀黄 )为试材 ,研究了栗疫病菌 (Cryphonectriaparasitica)菌块、CFE、ME等对板栗几丁质酶的诱导 ,测定了几丁质酶活性、比活性 ,并对其进行初步纯化。结果表明 ,菌块对板栗几丁质酶总活性、比活性的诱导效果最佳 ;接种后 35~ 4 0 h几丁质酶活性持续上升并达到高峰 ,之后开始下降。能够同时检测到板栗几丁质酶的内切酶和外切酶 ,以内切酶活性稍高。初步确定板栗几丁质酶的分子质量为 6 0 ku 相似文献
105.
本文以湿增压动力装置实验台为物理模型,为进行相关实验完成了速度、流量、扭矩等重要参数的测量,并以N16221硬件为基础,基于虚拟仪器平台LabVIEW研制了实验台的测试软件。新设计的测试系统是基于虚拟仪器平台的模块化系统,使得研究人员的大部分精力集中于所要实现的功能上,而不是以往繁琐的算法和重复的编程上,参数易于修改,缩短了系统开发的周期,能满足实验需求。 相似文献
106.
UASB的启动及其对畜禽废水处理的试验研究 总被引:1,自引:0,他引:1
利用UASB反应器处理畜禽废水的试验运行。结果表明,用畜禽废水直接启动UASB反应器是切实可行的,絮状污泥接种后经过54d的驯化,有机负荷由0.8kgCOD·(m^3·d)^-1提升到5kg COD·(m^3·d)^-1,进料COD浓度由800mg·L^-1提高到4000mg·L^-1,去除率基本稳定在85%以上;用UASB反应器处理畜禽废水也是切实可行的,畜禽废水经过UASB反应器处理,COD的去除率达到85%以上,同时对TN和TP也有一定的去除,且反应器较稳定,具有较强的抗冲击负荷能力。 相似文献
107.
Ferguson SM Brasnjo G Hayashi M Wölfel M Collesi C Giovedi S Raimondi A Gong LW Ariel P Paradise S O'toole E Flavell R Cremona O Miesenböck G Ryan TA De Camilli P 《Science (New York, N.Y.)》2007,316(5824):570-574
Dynamin 1 is a neuron-specific guanosine triphosphatase thought to be critically required for the fission reaction of synaptic vesicle endocytosis. Unexpectedly, mice lacking dynamin 1 were able to form functional synapses, even though their postnatal viability was limited. However, during spontaneous network activity, branched, tubular plasma membrane invaginations accumulated, capped by clathrin-coated pits, in synapses of dynamin 1-knockout mice. Synaptic vesicle endocytosis was severely impaired during strong exogenous stimulation but resumed efficiently when the stimulus was terminated. Thus, dynamin 1-independent mechanisms can support limited synaptic vesicle endocytosis, but dynamin 1 is needed during high levels of neuronal activity. 相似文献
108.
Mariana J. Ferreyra M. Carmen Menéndez-Sevillano Yanina Noe Luis R. Ibarra Antonio M. De Ron 《Euphytica》2017,213(8):186
In situ conservation of wild species is a method of conservation that allows keeping populations in their natural environments, and set the strategies for maintaining the natural populations. The Active Bank of Northwestern Argentina (BANOA) is in charge of the in situ conservation of wild populations of common bean (Phaseolus vulgaris L.) in Northwestern Argentina (NOA), and has an ex situ collection of 401 landraces and 221 wild accessions from the NOA. We evaluated the phenotypic diversity of 68 common bean wild populations from the NOA both in protected and unprotected areas, finding a moderate variation among them. Ten phenotypic reproductive characteristics related to pod and seed displayed significant differences in the analysis of variance; these traits together with the seed weight were the basis for the multivariate analysis. The cluster analysis ordered the populations in 12 groups but trends in geographical distribution or phenotypical variation were not recognized. For the conservation in situ of the wild bean populations, their diversity should be considered. Two types of populations can be highlighted: (i) candidates for in situ conservation in order to preserve the novel variation generated by convergence with cultivated sympatric germplasm (populations 433, 437, 471, 509, 513 and 517) and (ii) those whose phenotype represents clearly the wild status and should be preserved in situ as such in their current status (populations 480, 495, 496, 525 and 533). 相似文献
109.
110.
Weed Detection Using Canopy Reflection 总被引:1,自引:0,他引:1
For site-specific application of herbicides, automatic detection and evaluation of weeds is desirable. Since reflectance of crop, weeds and soil differs in the visual and near infrared wavelengths, there is potential for using reflection measurements at different wavelengths to distinguish between them. Reflectance spectra of crop and weed canopies were used to evaluate the possibilities of weed detection with reflection measurements in laboratory circumstances. Sugarbeet and maize and 7 weed species were included in the measurements. Classification into crop and weeds was possible in laboratory tests, using a limited number of wavelength band ratios. Crop and weed spectra could be separated with more than 97% correct classification. Field measurements of crop and weed reflection were conducted for testing spectral weed detection. Canopy reflection was measured with a line spectrograph in the wavelength range from 480 to 820 nm (visual to near infrared) with ambient light. The discriminant model uses a limited number of narrow wavelength bands. Over 90% of crop and weed spectra can be identified correctly, when the discriminant model is specific to the prevailing light conditions. 相似文献