The Maximum Edge-Edge Connectivity of Quasi-Regular Graphs

The edge-edge connectivity of a graph is defined,and a class of quasi-regulargraphs is proposed with a maximum edge-edge connectivity.     

A Study on the Algorithm of Draft-Tube in Computer Graphs Treatment

The geometrical characteristics of high-narrow-type draft tube are analyzed. The algorithm is designed as having the projection before seeking its envelope. A series of detailed graphs are drawn. An excellent condition is created for construction of high-narrow-type draft tube.     

A Class of Hypergraphs with the Best Connectivity

A jumping sequence is proposed,so that a class of r-uniform hypergraphs with nvenices and n edges is constructed. Then by analysing the connectivity of its two-section (graph),this class of hypergraphs is proved to have the best connectivity. The class of hypergraphs can beused to desisn the optimal fault-tolerant multibus computer systems.     

A Numerical Method for Transmission Line Equations

Transient analysis of transmission line has recently been received more attention because operating speeds in high-speed digital electronics are increasing. Transmission line equations are hyperbolic partial differential equations, firstly this paper deduces how to change transmission line equations into quasilinear differential equations , thus the transmission line equation numerical result is gotten by computing the differential formation of quasilinear differential equations. The constraint of voltage and current is be considered and lumped equivalent circuit mode at boundary network collaborated at the same time in finding boundary conditions. Finally the paper computes transient response of transmission line with two typical boundary conditions. Numerical result shows that this approach is an effective way. It is explicit algorithm with less CPU consumption which can get time field response directly. The agree-upon effective way does be frequency field method, however it could not get time response unless the numerical inverse laplace transformation (NILT) be introduced. Thus this approach is more effective than FFT algorithm.     

Discussion about Some Questions of the Profile Line

This paper discusses some questions about the profile line of space geometry,such as the judgement of the parallelism of the two profile lines with the same directions and the visibility about the skew lines and the reappeared points of profile lines, which make the solution of some questions in space geometry more easy than those commonly used.     

小麦T型细胞质雄性不育保持系线粒体DNA片段转化不育系的初步研究

细胞质雄性不育在植物界普遍存在,其不育机理一直是人们研究的热点。采用花粉管通道法,利用T型细胞质雄性不育保持系75-3369B线粒体的基因文库,选取其中所载外源片段较大的重组子转化T型不育系小麦75-3369A,结果重组子ME252和ME317的转化后代变成可育,表明线粒体的部分片段可以使细胞质雄性不育系的育性发生转变。     

SSR对甜菜骨干单胚雄性不育系和保持系的遗传多样性分析

为了配制优良单胚杂交组合,避免基因组成重复,提高育种工作效率,利用14对SSR引物对41对甜菜骨干单胚不育系和保持系进行检测。结果表明,14对SSR引物共产生93条扩增带,其中多态性条带76条,平均每对引物扩增多态性条带5.4条,平均多态性百分比为81.7%,平均遗传距离为0.3572,平均遗传相似系数为0.6996。不同品系的平均遗传相似系数为混合(0.7549)>兰45-46(0.7513)>兰71-72(0.7493)>兰19-20(0.7465)>兰85-86(0.7337)。根据UPGMA方法进行聚类,在遗传距离0.20处,可将82份供试材料分为两大类群。结果表明,供试的甜菜单胚雄性不育系和保持系的遗传多样性较丰富,不同品系的不育系和保持系材料之间的遗传基础有差异。     

普通小麦K,V型雄性不育系,保持系过氧化物酶同工酶的比较研究

利用聚丙烯酰胺垂直平板凝胶电泳法，对普通小麦Ｋ、Ｖ型雄性不育系，保持系在不同发育时期的雄蕊，雌蕊，旗叶的过氧化物酶同工酶进行了系统研究，结果表明，Ｋ、Ｖ型不育系，保持系在不同发育时期的花药具有不同的酶谱，根据酶带数量和酶活性的变化，发现Ｋ、Ｖ型不育系之间在花粉败育时间上有较大差异，认为Ｖ型不育系败育的关键时期是“单核期”而Ｋ型不育系为“二核期”与细胞学观察结果相吻合，Ｋ、Ｖ型不育系，保持系之间在不     

粳型恢复系耐冷性鉴定

将38个粳型恢复系在海拔2200 m的昆明市西山区团结镇田间自然条件下种植,全生育期间用自然山泉水灌溉,以当地主栽水稻品种滇系16号作对照进行分析,鉴定其耐冷性(抗寒性).试验结果表明:参与鉴定的38个粳型恢复系中,耐冷性(抗寒性)极强的恢复系仅有1个,耐冷性(抗寒性)强的恢复系有11个,说明现有的粳型恢复系的耐冷性(抗寒性)十分匮乏;粳型恢复系的耐寒性(抗寒性)与空秕率之间呈明显负相关关系,提高恢复系的耐冷性(抗寒性),应降低空秕率.     

棉花晋A细胞质雄性不育系酶活性的研究

酶活性的变化与育性有着密切的关系。对与线粒体有关的过氧化物酶、超氧化物歧化酶、细胞色素氧化酶和琥珀酸脱氢酶进行了酶活性分析。结果表明:在花粉发育的各个时期晋A不育系的酶活性比其保持系明显要低。这表明了不育系与其保持系之间体内代谢强度的差异,也说明酶活性的变化与雄性不育现象有着直接的关系。     

高粱雄性不育系、保持系正负极向过氧化物酶同工酶的电泳比较

对高粱雄性不育系、保持系不同生长发育阶段叶片中的正、负极向过氧化物酶同工酶进行了检测。结果表明,叶片中正极向过氧化物酶同工酶谱两者基本相同,说明正极向过氧化物酶在不同生长发育时期是稳定的。负极区域中,在叶片发育过程中有2条酶带消失,证明在这个区域中遗传信息出现顺序表达现象。花粉粒发育过程中,不育系的正极向过氧化物酶带始终多于保持系。作者认为,不育细胞质基因可影响编码过氧化物酶的核基因的表达,引起雄性不育。不育细胞质基因可能也同时具有调节基因的功能,表现为具有解除阻遏的作用,使不育系花粉粒发育过程中部分过氧化物酶基因得以表达;而保持系不具有这种解除阻遏的细胞质不育基因,使部分基因仍处于阻遏状态,造成保持系中过氧化物酶同工酶谱带少于不育系的现象。不育细胞质基因的这种调控作用,同样有可能影响核基因遗传功能的正常发挥,引起核质之间的不协调而导致雄性不育。     

Lightning Shielding Simulation Model of Transmission Line

Transmission lines are easily hit by lightning, and lightning shielding failure is an important reason of lightning accidents of transmission line. So researches on lightning shielding of transmission line should be strengthened. On the basis of the abundant understand to known lightning shielding models of transmission line, a new lightning shielding simulation model of transmission line is presented in the paper. In this model, the effect of attracting lightning of upward leader is considered reasonably, and the method of variable descending step is adopted to simulate the descending process of lightning leader. The simulation calculating results show that the model is in good agreement with field experience of transmission line. It can guide lightning shielding design of transmission line and estimate the performance of lightning shielding of transmission line.     

垄沟覆膜集雨边行玉米与中行玉米竞争对产量的影响

为了给旱地玉米水分利用和产量提高提供理论依据和科学指导,此研究从植物种内竞争的角度出发,来探讨垄沟覆膜集雨玉米如何高效利用水分和提高产量。试验设有2种类型的垄沟覆膜集雨,它们的沟宽均为60 cm,而垄宽分别为30 cm和60 cm。设有高、低2种种植密度,高密度每沟种植三行,低密度每沟种植两行。裸地为对照,同样设有高低2个种植密度。结果表明,垄沟覆膜集雨具有聚雨保墒的作用。整个生育期间的玉米单株和单位面积生物量,以及收获时的生物产量、籽粒产量和水分利用效率,垄沟覆膜集雨都显著高于裸地。相同垄宽的垄沟覆膜集雨,当密度较高时能明显提高玉米的生物量、籽粒产量及水分利用效率。受密度效应的影响,8月15后60 cm和30 cm垄宽的高密度垄沟覆膜集雨,它们中行玉米的单株生物量都显著低于它们边行玉米的单株生物量;收获时30 cm垄宽的垄沟覆膜集雨中行玉米的收获指数较低,导致该处理较低的收获指数和较低的产量。在所有的处理里,60 cm垄宽的高密度垄沟覆膜集雨处理的单位面积产量最高。总之,高密度、宽垄垄沟覆膜集雨的种植模式是提高玉米产量和水分利用的一个重要方面。     

系祖轮配对维持并提高豫州褐壳蛋鸡Ⅲ系生产性能的研究

对豫州褐壳蛋鸡Ⅲ系采用系祖间轮配的选配方法，经过连续3个世代的选育，开产日龄推迟5．72d，开产平均蛋重减少0．87g，72周龄平均蛋重增加2．82g、蛋数增加8．62枚，蛋品质维持在较高水平，蛋壳颜色变深。说明对已育成的纯系采用系祖间轮配的选配方法，可以维持并提高其生产性能。     

基于性状和分子标记的小麦抗旱近等基因系的分离

创建小麦‘宁春4号’抗旱近等基因系,为其在生产中的应用和抗旱遗传改良提供有利用价值的材料。利用重组自交系(RILs)合适世代(F₆或F₇)的单株具有一定杂合率的特点,采用性状和分子标记分离近等基因系的方法,在‘宁春4号’/‘宁春27号’RILs一个家系RIL-97内分离出‘宁春4号’抗旱近等基因系,经抗旱性及特征特性鉴定表明,该近等基因系抗旱性较强,其他形态特征特性与‘宁春4号’基本一致。这些近等基因系可进一步用来精确定位抗旱相关性状QTL位点。利用RILs群体合适世代结合分子标记是快速构建近等基因系的有效方法。     

线的特质与园林景观设计浅析

线是造型要素中最基本的元素,也是设计师表达设计理念的基本语言。通过对线的特质、线在园林景观中运用形式以及具体应用的研究,使设计师更加明确线的灵活运用在园林景观设计中存在的精神内涵和艺术价值,以提高中国现代园林设计水平。     

洋葱细胞质雄性不育系及保持系小孢子发生的细胞学观察

为揭示洋葱细胞质雄性不育系小孢子的败育时期,利用石蜡切片技术对洋葱细胞质雄性不育系8A及其保持系8B的小孢子发育过程进行观察和比较。结果表明：石蜡切片洋葱细胞质雄性不育系8A和保持系8B造孢组织时期小孢子的生长发育没有明显的差异;洋葱不育系8A花药绒毡层在花粉母细胞时期就与中层完全分离,并逐渐膨大挤压花粉母细胞,最后逐渐降解。其降解后的残余物侵入药室,与小孢子混合粘连在一起,占据药室的一部分空间,并且不能供给小孢子生长发育所需要的营养物质,最终小孢子降解,花药败育。试验明确了洋葱细胞质雄性不育系8A的小孢子败育时期为花粉母细胞时期。因此,在洋葱雄性不育系8A的不育机理研究中,应重点在花粉母细胞时期进行深入研究。     

Channel Characteristics of Low Voltage Power Line

In order to make good use of power line carrier to communicate, it is necessary to analyze the time-variable, impedance,attenuation and noise characteristics of low voltage power line. The waves of every characteristic have been experimented. At the same time, aiming at these characteristics, some available measures are given in order to conquer the disadvantage factors. The experimental results show that some suitable carrier communication modes must be adopted to realize ideally the carrier communication on low voltage power line.