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1.
为探究新型纳米级无机杀菌剂纳米铜(nano-copper,NC)处理对切花的保鲜效应,以非洲菊(Gerbera jamesonii)‘红艳’切花为试材,观测不同浓度NC单独处理及其与蔗糖组合溶液瓶插处理对非洲菊瓶插寿命、观赏品质和水分关系的影响。结果表明,与去离子水处理(对照组)相比,1、3、5 mg/L NC单独处理对非洲菊切花没有明显的保鲜作用,而各浓度NC加3%蔗糖的组合处理均可有效延缓和减轻该切花的花朵萎蔫和花茎弯折等品质劣变症状。其中,以1、3 mg/L NC+3%蔗糖的组合处理效果最为突出,可显著延长该切花的瓶插寿命,并使花枝瓶插期间的鲜重、水分吸收量和水分平衡值均显著高于对照和NC单独处理。试验表明适宜浓度的NC加蔗糖组合溶液瓶插处理对非洲菊‘红艳’切花具有良好的保鲜作用。  相似文献   

2.
3.
This paper proposes a new method of generating a rough cut Numerical Control(NC) codes directly from industrial computerized tomography(CT) slice images for the products which work-piece did not need to be redesigned.The contour structure data of the work-piece are obtained by the threshold segmentation,edge extraction and contour tracing. The inner and outer contours are judged,and the tool radius compensation and the allowance reservation are performed by offsetting the contours according to the judgments. The authors generate the rough cut NC code cut area distinguishing and rough cut path generating in a slice by slice manner. In contour offsetting step, a new approach is proposed to judge inner and outer contours. A software system is developed to generate NC codes. An example is used to verify this approach and results show the feasibility and validity of the approach.  相似文献   

4.
Improving the host genotype is one method of increasing biological nitrogen fixation by Bradyrhizobium in symbiosis with peanut (Arachis hypogaea L.), but host-strain interactions also must be considered. The objective of this study was to estimate the effect of Bradyrhizobium strains on the inheritance of traits related to nitrogen fixation. Eight parents and the F1 generation of a diallel cross were evaluated in symbiosis with two bacterial strains for combining ability in a factorial arrangement in the greenhouse. The parents represented three taxa of cultivated peanuts. The two Bradyrhizobium strains NC 92 and NC 123 produced different general and specific combining ability, maternal (reciprocal general) effects, and reciprocal specific effects for the host genotypes. With strain NC 92, the peanut cultivars NC 7 and NC Ac 2821 had the best general combining ability for all traits evaluated; while, with strain NC 123, Robut 33-1 exhibited a high general combining ability (GCA) for nitrogenase activity and specific activity. Genotype NC Ac 2821, when inoculated with strain NC 123, had a negative GCA effect for nodule number, while with strain NC 92 this cultivar had the highest GCA effect. The importance of strain selection in evaluating lines in a breeding program is discussed.  相似文献   

5.
To subgrade the shape-curve roughness of a contact roller,the three-coordinate CNC milling machine has been enlarged as a CNC lathe and CNC grinding machine so that the contact rollers can be lathed and grinded by the same installation and NC program. Furthermore,an NC program of dealing with complex curve contact rollers has been developed. Acceptable metal shaving contact rollers of cycloidal gears and involute gears in shape grinding have been manufactured with this method.  相似文献   

6.
The Graphic transfer technique applied in control software of a profile-followed robot for grinding turbine surface is described. Projection transformation in any axis of 3D camber on a display coordinate is realized by using homogeneous transfer matrix, which provides user with visual information of grinding and processing. 2D graphic linear transfer technique is used to provide user with uniform NC programming format and to carry out 2D grinding process for 3D profile. 3D non-linear transfer technique is successfully used to solve a series of difficult problems including coordinate transfer of controlled points in multi-coordinate system, the attitude adjustment of grinding and constant pressure grinding. All the mathematics methods used are demonstrated in practice feasible and efficiently.  相似文献   

7.
The peculiar non linear error in the 5 axis NC machining is studied. An improved tool step determination method for the 5 axis NC machining is proposed, in which the non linear error is compensated. Both the arc chord error and the non linear error are considered when computing the tool step, and the comprehensive error is taken as the function of the tool path parameter. Due to the difficulty of gaining the derivative of this function and the tool step according to the prescribed tolerance, the secant method is improved to guarantee the real solution locating in the converging range which is adopted to compute the tool step. The implementing example shows that the proposed method can compensate the non linear error effectively with meeting the prescribed tolerance. The exact tool step can be gotten efficiently with the improved secant method.  相似文献   

8.
利用航天诱变方法获得烟草品种NC89的突变体NC89-M,与野生型相比,NC89-M叶形呈宽椭圆,叶面褶皱,叶缘呈锯齿状。为明确烟草航天诱变突变体NC89-M叶形突变机理,挖掘突变体叶形突变基因,利用NC89-M与烟草品系2014-168杂交获得F2群体,对F2群体遗传分析表明突变体叶形性状受1对显性主效基因控制。通过混合集团分离法,确定SSR标记PT60795与叶形性状连锁。利用已有的突变体基因组序列信息,开发InDel标记最终将突变基因nc89m定位于标记PT60795与InDel5之间,遗传距离分别为2.9 cM和4.4 cM。在该区间内发现在叶片中高表达的基因Nitab4.5_0000008g0880.1编码区第1 294个核苷酸发生突变,由腺嘌呤突变为胞嘧啶,其编码氨基酸由酪氨酸突变为天冬氨酸,因此将其作为nc89m的候选基因。本研究为Nitab4.5_0000008g0880.1的基因克隆及功能验证打下基础。  相似文献   

9.
粗山羊草的细胞质对小麦抗旱性的影响   总被引:17,自引:0,他引:17  
杨凯  朱志华 《作物学报》1997,23(1):50-55
本文对具山羊草南(D型)的冬小麦核质杂种NC4、NC37及其核共体亲本丰抗12(细胞质为B型)在水分胁迫下的存活率、叶片相对含水量、细胞质膜透性、细胞渗透势等抗旱指标和叶算了细胞蛋白进行了检测,试验表明,粗山羊草细胞质能增加抗旱能力和影响叶片细胞蛋白质的表达,选育具有优良细胞质效应的质杂种小麦是改良小麦抗逆性的有效方法之一。  相似文献   

10.
C. G. Liu    Y. W. Wu    H. Hou    C. Zhang  Y. Zhang  R. A. McIntosh 《Plant Breeding》2002,121(5):407-410
Differences between alloplasmic lines and euplasmic controls indicated consistent beneficial effects of Aegilops crassa cytoplasm on common wheats. In general, the agronomic performance of alloplasmic lines was superior to that of euplasmic controls; the significant differences observed were ascribed to nucleus‐cytoplasmic (NC) interactions. A number of useful genetic attributes, for example, high yield, good quality and salt tolerance, were identified. A new NC hybrid variety ‘Xiaoshan 2134’ was bred. Field trials showed that the yield NC heterosis of ‘Xiaoshan 2134’ was 13.9% and the yield of ‘Xiaoshan 2134’ was at least 20% higher than that of a control variety widely grown in North China. The results suggested that Ae. crassa cytoplasm could broaden the genetic base of common wheat and improve common wheat cultivars by utilizing NC heterosis.  相似文献   

11.
土壤盐渍化程度日趋严重,成为影响作物生长发育、制约产量的一个主要环境因子,明确玉米苗期耐盐的光合作用机制尤为重要。本研究采用水培法,对已耐盐性鉴定筛选的强耐盐型自交系(B46)和盐高度敏感型自交系(NC236)为材料,分析二者在盐胁迫条件下光合作用的变化。低浓度盐(55 mmol/L NaCl)胁迫条件可促进玉米自交系幼苗叶绿素含量的增加,较NC236,B46增幅较大;随着NaCl浓度进一步增加,两玉米自交系幼苗叶绿素含量均呈下降趋势,较NC236,B46降幅较小。在盐胁迫条件下,较NC236,B46的Fv/FmFv/FoqPFo的变化幅度较小,NPQ的增幅较大。B46在NaCl浓度0~165 mmol/L范围内为气孔关闭引起的气孔限制,220 mmol/L时为光合系统遭到破坏引起的非气孔限制;NC236在NaCl浓度为0~110 mmol/L范围内为气孔限制,165~220 mmol/L时为非气孔限制。  相似文献   

12.
不同变黄温度对烟叶主要质量性状的影响   总被引:1,自引:0,他引:1  
为改善烤烟NC297和NC102烤后烟叶的外观质量和内在品质,以这2个品种上、中和下3个部位的烟叶为材料通过控制变黄阶段干球和湿球的温度,找出2个品种优良外观质量和内在品质的形成的变黄温湿度。结果表明:烤烟NC297下部叶和中部叶,变黄温度为38℃,干湿差2~3℃的经济性状、外观质量和主要化学成分协调性最好;上部叶,除外观质量,处理1(温度为36℃,干湿差2~3℃)的经济性状和化学成分协调性最好。烤烟NC102下部叶,经济性状、外观质量和化学成分协调性均为处理3(温度为40℃,干湿差2~3℃)最好;中部叶,除化学成分的协调性,处理2(温度为38℃,干湿差2~3℃)经济性状和外观质量的协调性最好;上部叶,除化学成分的协调性,处理1(变黄温度为36℃,干湿差2~3℃)经济性状和外观质量最优。说明烤烟NC297下部和中部叶变黄阶段温度应控制在38℃,上部叶应控制在36℃;烤烟NC102下部叶变黄阶段温度应控制在40℃,中部叶应控制在38℃,上部叶应控制在36℃。  相似文献   

13.
Under the mode of customization-oriented multi-varieties and small-batch production, the requirement of design and manufacturing integration exists in sheet metal processing shops, which has the characteristics of great varieties of sheet metals, huge design data and heavy production tasks. To meet the requirement, an integrated operation mode for sheet metal processing shop of electrical equipment is presented. The mode realizes the information sharing and business collaboration from the sheet metal 3D CAD, 2D outspread, process design, optimal sheet metal layout, NC programming to NC machining. The integration framework based on service oriented architecture(SOA), function structure and operation process of the system is constructed. The system has been applied to an electrical equipment manufacturer in Chongqing, and good results are obtained.  相似文献   

14.
周林泉 《粮食储藏》2011,40(1):24-25
设计出一种粮仓窗户远程自动控制系统。根据仓内外的温度和湿度变化,自动开启或关闭窗户及通风机械,实现粮仓的自动通风,自动控制。该系统可与粮情检测系统、通风控制系统等结合,组成粮仓自动化管理系统。  相似文献   

15.
Decomposed discrete models, can be used to design load frequency' controllers in multi-area power systems.Considering the exchanging real power in tie-lines as a measurable disturbance, the multi-area power system is decomposed into several subsystems.On the basis of generalized minimum variance control principles, an expanded control rule is induced. Using discrete models, the proposed method greatly decreases the number of varialles in be measured and simplifies the control system. The method is illustrated with a two-area power system example and its simulation Jesuits.  相似文献   

16.
奶牛妊娠的早期诊断至关重要,妊娠相关糖蛋白6(PAG6)是母体胎盘组织分泌至外周循环中的特异蛋白质,因此,本研究致力于制备牛妊娠相关糖蛋白6快速检测试纸条。制备牛妊娠相关糖蛋白6多克隆抗体,将其稀释后加样至NC膜上,通过固定和封闭制备出一种可检测boPAG6的快速检测试纸条,在试纸条上加入待检血清进行孵育后洗涤,再加入二抗孵育后洗涤,最后加入显色液显色后进行快速检测。标准化快速检测试纸条是将抗体用PBS稀释成10μg/mL点样至NC膜上,在37℃温箱中固定抗体30 min,经5%的脱脂奶粉封闭后制成。待检血清滴加至试纸条后,在37℃温箱中孵育1 h后,进行洗涤和二抗孵育,最后在DAB显色试剂盒作用下显色3 min即可判定。临床检测的初步应用表明,在未孕与怀孕奶牛的混合血清中仍然可以判定是否怀孕,快速检测试纸条特异性强;血清在稀释3200倍的最低检测限时,快速检测试纸条的敏感性良好;而且该结果与ELISA的符合率在80%之上。试验重复性良好,并能在4℃和-20℃条件下保存2周。建立了一种奶牛早期妊娠诊断的快速检测试纸条并应用于初步的妊娠诊断。  相似文献   

17.
The effect of functional rice giant embryo and Aranghyangchal on the glucose metabolism and antioxidative defense status in high fat-fed C57BL/6N mice were investigated. The animals were randomly divided into four dietary groups: normal control (NC), high fat (HF), and high fat supplemented with giant embryo rice (HF-GE) or Aranghyangchal rice (HF-AR). After 8 weeks of feeding them with experimental diets, the HF mice exhibited a marked increase in the blood glucose concentration, plasma insulin level, and lipid peroxidation and a significant decrease in the hepatic glycogen level relative to the NC group. On the other hand, diet supplementation of the rice samples suppressed this high fat diet-induced hyperglycemia and oxidative stress through inhibition of the glucose-regulating enzymes and activation of the antioxidant enzymes. These findings demonstrate that the giant embryo and Aranghyangchal rice may be beneficial as biomaterials in the development of functional food with hypoglycemic and antioxidative properties.  相似文献   

18.
8份新引优质烤烟品种资源综评   总被引:3,自引:0,他引:3  
8个从美国、巴西引进的烤烟新品种,经检疫合格后在大田进行品种比较试验,对照为K326。试验结果表明:除OX414属多叶型的品种,栽后68d现蕾外,其他品种现蕾期、中心花开放期等与对照相近。各品种都没发黑胫病和根结线虫病,赤星病和TMV较轻。公顷产量最高的是OX414,其次是NC72“Primed”,第三是NC71。公顷产值最高的是K326,其次是OX414,NC72“Primed”第三,这些品种间无显著差异。NC100、K326、NC72“Primed”等品种上等烟比例、均价、级指和产指4号较高。综合起来看,OX414产量高,K326、NC100、NC71公顷产值、上等烟、均价、级指等较高。COM烟和RGH61各项经济指标都较低。  相似文献   

19.
钟冠昌  张荣琦 《作物学报》1989,15(3):230-236
以长穗偃麦草(Elytrigia elongata=Agropyron elongatum,2n=70)为母本,普通小麦为父本,进行核置换回交,现已获得第14次回交的核质杂种材料。根据育性和生活力的表现以及细胞遗传学分析,长穗偃麦草-普通小麦核质杂种可分为以下类型:(1)生长正常,育性较好,染色体构型为21″W+1′Eev;(2)生长正常,完全不育或育性很低,染色体构型  相似文献   

20.
An improved predictive control method is presented to compensate the random time delay in the networked control system. The feedback time delay is compensated by predictive controller based on softened increment input strategy. The forward time delay is unknown for controller, so an extra feedback loop is added to compensate the delay by estimating the error between the actual control signal effected on plant and the output of controller in historical moment. For the controlled system with unknown or slowly varying parameters, the networked feedback correction algorithm is discussed based on a modified recursive least-squares identi cation algorithm. The system stability is analyzed and the simulation results show that the time delay in the networked control system can be accurately compensated. The excellent network performance is ensured with this strategy.  相似文献   

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