Modeling by Bond Graph and Simulation for a Metal Pushing Belt Continuously Variable Transmission System

Continuously variable transmission is the ideal transmission mode, the Metal Pushing Continuously Variable Transmission (CVT) is the most mature CVT used in vehicle at present. By studying the transmission mechanism and ratio change characteristics of Metal Pushing Continuously Variable Transmission system, and using the bond graph theory, a bond graph model of continuously variable transmission is established in this paper, and the state space function is derived. Based on the model, The simulation of transmission characteristics of a CVT car is studied, the simulation result shows that the dynamic characteristics of continuously variable transmission could be expressed in this model. The research results can provide the theoretical analysis method and design basis for CVT vehicle.[WT5HZ]     

我国热带水果贮运保鲜现状及进展

对我国热带水果的特性及贮运保鲜发展现状进行了论述,并对近年来研发的一些先进保鲜技术和进展进行了介绍.根据国际水果市场的发展趋势,提出了我国热带水果采后处理、贮运保鲜与国际接轨的对策及措施,并对今后热带水果贮运保鲜发展方向进行了分析与展望.     

临沭县冬小麦复合微生物肥效对比试验

为了讨论复合微生物肥料在冬小麦上的肥料效应,开展同等地力条件下,冬小麦使用复合微生物肥料(含有机质)和测土配方研制的小麦专用配方肥(大量元素肥料)对比试验。试验表明:施用复合微生物肥料(含有机质),对改善冬小麦的农艺性状、增产增效等均有良好的效果。     

不同稀释剂对猪冷冻精液的影响

手握法采集12月龄大约克种公猪精液,在37 ℃下离心,弃去精清,收集浓缩段富含精子部分,用7种不同的稀释液进行稀释,应用液氮熏蒸法制作颗粒冻精。结果表明,在7种稀释液中,7号稀释液 优于其他6种稀释液(p<0.05);与其他的冷冻保护剂相比,甘油的冷冻保护性能较好(p<0.01),其适宜浓度为2~4 ml·l-1;干解冻（40~45 ℃）效果优于湿解冻,解冻后精子活率达0.46~0.49（p<0.05）;稀释液中添加安钠咖可有效地延长精子的冻后存活时间(p<0.01)。     

利用种子醇溶蛋白选育玉米姊妹系和姊妹种的研究

不同分离世代产生的姊妹系配制的早晚代姊妹种在农艺性状、产量和种子蛋白图谱上存在很大的差别。大多数早代姊妹种种子蛋白谱带具有双亲的互补带，并表现出较强的优势，晚代姊妹种的种子蛋白图谱基本上与亲本相同，优势不及早代姊妹种明显。     

Analysis of Load-bearing Characteristics of Concrete Pile Composite Foundation

Some conclusions were drawn from two groups of in-site tests on concrete pile composite foundations. In the tests, it was found that the pressure under the rigid loading slab is different, in which the pressure under the center of the slab is the less and under the edge of the slab is the biggest. The pile-soil stress ratio is not a constant; it increases with the adding of the load. Most of the pile-soil ratio vary from 9 to 13 in these tests and the load that the piles share can be more than seventy percent of the whole load. It was proved that the bearing capacity of the concrete pile composite foundation is high with a little settlement, so it will be used more and more in the future.     

水稻纹枯病抗性关联分析及抗性等位变异发掘

采用苗期微室接种鉴定法,用144个分布于水稻全基因组的多态性标记,利用TASSEL软件GLM (Q)、MLM (Q+K)和MLM (PCA+K) 3种模型对456份水稻材料组成的自然群体进行纹枯病抗性关联分析。结果发现,有13个标记位点至少在两种模型中均被检测到与纹枯病抗性显著关联,单个位点可解释表型变异的1.84%~8.42%;其中10个标记位点位于以往报道的连锁定位的抗纹枯病QTL附近,3个标记位点(RM1036、RM5371和RM7585)是未曾报道的新的抗病相关位点。抗性等位变异RM7585-150对纹枯病发病病级减效效应最大;有259份材料携带抗性等位变异RM5371-129,占供试材料总数的56.8%,只有26份材料携带抗性等位变异RM1036-82,占供试材料总数的5.7%。水稻纹枯病发病病级与其含有的抗性等位变异数量呈极显著的负相关。本研究结果将为水稻抗纹枯病分子标记辅助育种提供理论依据。     

陕西省不同年代玉米品种产量和氮效率性状的变化

明确陕西省不同年代玉米产量和氮效率性状响应氮肥的变化趋势,对西北旱区玉米高产氮高效品种选育具有重要的实践意义。本文以1981—2010年间陕西省12个玉米主栽品种为材料,于2011年和2012年在典型旱区陕西长武进行3个氮水平(0、120和240 kg hm–2)的田间试验,分析了不同年代玉米品种农艺和氮效率性状变化趋势。结果显示,不同年代玉米品种籽粒产量随氮水平增加而提高,在施氮0、120和240 kg hm–2处理下籽粒产量增益分别为每年46、65和83 kg hm–2。所有氮水平下2000—2010年间品种产量和生物量显著高于1980—1989年间品种,而秸秆产量变化不明显;现代玉米品种(2000—2010年)产量的增加归因于穗粒数、千粒重和生物量的提高。不同年代玉米品种消光系数随氮水平增加而降低,说明现代玉米品种(2000—2010年)较老品种(1980—1989年)叶片直立,截获更多的光能,致使产量和生物量高。随着年代的递进,玉米品种氮肥农学利用率呈递增趋势,在低氮水平下现代品种氮肥利用效率最高,且显著高于老品种。氮肥农学利用率与氮吸收效率(NUpE)和花后氮素积累量呈显著相关(r=0.75;r=0.72),而与氮生理效率(NUtE)和花前氮素积累量相关性不显著(r=0.42;r=0.39)。说明现代玉米品种氮肥农学利用率提高主要来自氮肥吸收效率和花后氮素积累量的增加。上述结果表明,陕西玉米育种应注重穗粒数、千粒重、氮吸收效率性状和株型结构改良,低氮环境压力选择将有助于旱区玉米高产氮高效新品种培育。     

State of charge estimation of lithium iron phosphate batteriesbased on adaptive Kalman filters

The Kalman filter algorithm can be used to estimate the state of charge (SOC) of power batteries, however, it easily causes divergence due to uncertain of system noise and its estimation performance is affected by model. An adaptive Kalman filter algorithm is adopted to dynamically estimate SOC of lithium iron phosphate batteries for application in electric vehicles. At first, an equivalent circuit model, appropriate for SOC estimation is built after studying battery models. Then some charging and discharging experiments are carried out for parameter identification and the results are verified. At last, the adaptive Kalman filter algorithm is used on this model for on-line SOC estimation under unknown interfering noise. Simulation results show that adaptive Kalman filter method can correct SOC estimation error caused by tiny model error online, and the estimate accuracy is higher than Kalman filter method. Adaptive Kalman filter algorithm can also correct the initial error. Full-cycle test in electric vehicles proves that the algorithm is appropriate for SOC estimation of lithium iron phosphate battery.     

不同类型苜蓿愈伤组织细胞形态结构比较

为了找到植物胚性愈伤组织的诱导方式,从而形成完整的单克隆细胞体细胞胚诱导体系,为进一步的体细胞诱变育种奠定基础,以苜蓿为试材,通过徒手制片法,对不同类型愈伤组织的细胞形态和结构差异性进行了观察比较。结果显示：巨大型愈伤组织细胞较大,其体积是松散型的4．5倍,是硬型的9倍;其中有48％的细胞具有5～8个较大液泡,松散型愈伤中89％的细胞具有2～4个小液泡,而硬型愈伤中97％的细胞具有1个中央大液泡。松散型愈伤的细胞中叶绿体较多,其数量是巨大型的4．65倍,硬型愈伤细胞中的叶绿体聚集成团,每团中有叶绿体3～5个。总之,巨大型愈伤的细胞分化程度较低,但液泡化明显;硬型愈伤的分化程度高,组织较老化;松散型愈伤细胞未分化,液泡化程度低,胚性愈伤特征明显,适合用于体细胞胚的诱导。