Cu^2＋、Zn^2＋复合条件下Cd^2＋在陕西5种土壤中的吸附

通过平衡吸附的方法,研究了Cd2＋在单一及与Cu2＋、Zn2＋复合条件下,在陕西塿土、黄绵土、黑垆土、黄褐土、砂土5种土壤中的吸附特征,并通过多重相关分析探讨了其吸附机制。结果表明,在20、30℃条件下,Cd2＋在各供试土样中吸附等温线总体上呈H或L型等温线形式,黑垆土对Cd2＋总是吸附最强,而砂土的吸附总是最弱;Cd2＋吸附的温度效应呈现升温负效应特征,塿土土样中,Cu2＋的共存对其温度效应影响较大,而在其他4种土样中Zn2＋的共存具有较大影响;Cu2＋、Zn2＋的共存均降低了Cd2＋的吸附量,具有显著的拮抗作用;Freundlich模型是描述Cd2＋吸附等温线最佳模型。相关分析结果表明,Cd2＋在土壤中的吸附主要以电性引力吸附为主,Cu2＋的共存主要和其与土壤有机质之间的络和吸附等化学吸附作用有关,因此其对Cd2＋以化学竞争性吸附的影响相对较弱,而Zn2＋共存吸附与Cd2＋吸附机制类似,因此表现出Zn2＋共存对Cd2＋吸附影响较大的特点。     

草酸对不同土壤中Cd Zn吸附及其交互作用影响的初步研究

研究了草酸对Cd2＋、Zn2＋单一及复合条件下在陕西塿土、黄绵土、黑垆土、黄褐土、砂土5种土壤中的吸附特征,并探讨了草酸的影响机制。结果表明,除在低Zn2＋平衡浓度下,5种土壤中草酸促进了Zn2＋的吸附外,总体上在Cd2＋、Zn2＋单一处理及其复合处理中,草酸降低了土壤对Cd2＋、Zn2＋的吸附。草酸既没有改变塿土、黑垆土吸附能力最强、砂土吸附能力最弱的结果,也没有改变Cd2＋、Zn2＋之间的相互拮抗作用。草酸对Cd2＋、Zn2＋吸附的影响机制主要在于其与Cd2＋、Zn2＋形成络合物。草酸主要通过降低电性引力的方式减弱土壤对Cd2＋的吸附能力,而对于Zn2＋,在低平衡浓度下,草酸对Zn2＋吸附的促进作用来源于在土壤氧化物矿物表面形成少量的三元表面络合物的桥键合效应,在高平衡浓度下,对Zn2＋吸附的抑制作用来源于草酸对土壤有机质化学吸附点位的竞争。对Cd2＋、Zn2＋吸附起决定作用的依然是土壤本身性质。     

不同土地利用方式对黑土有机无机复合体的影响

采用超声波分散、颗粒大小分组法研究不同土地利用方式下黑土有机无机复合体组成及有机碳的分布特征。不同土地利用方式下黑土均以细砂级复合体为主,有机碳含量随粒径增加而减少,C/N比随粒径增加而增加。NP和NPM处理比NF处理土壤<20μm粒级复合体含量减少,>20μm复合体含量增加;草地与裸地相比<20μm粒级复合体含量减少,>20μm复合体含量增加。土地利用方式不同,土壤固碳的机制是不同的,草地生态系统的土壤固碳潜力高于农田土壤。施肥和有机质的输入使土壤各粒级复合体中的有机碳含量增加;使>20μm粒级复合体固持的SOC量比例增加,表明在土壤有机质含量增加的情况下,有机质有向大粒级复合体的积累增加。     

紫色土和黄壤草本根土复合体抗剪性能试验研究

以重庆常见的紫色土和黄壤草本根土复合体为试验对象,研究含水率和含根量对土壤抗剪强度的影响,结果表明:①在试验含根量范围内,根系提高了土样抗剪强度,黏聚力和内摩擦角随含根量的增加而增大,但存在最优含根量区域,黄壤最优含根量为1%,紫色土最优含根量为0.6%;②在试验含水率范围内,黏聚力和内摩擦角受含水率影响显著(P<0.05),且随含水率的增加表现为先增加后减少,存在最优含水率,黄壤最优含水率为20%,紫色土最优含水率为25%;③在试验含水率范围内,含根量对紫色土黏聚力和内摩擦角的影响比黄壤大。     

酿酒曲对柑橘梨汁复合酒发酵工艺的影响

通过添加不同含量的酿酒曲到柑橘梨汁复合液进行试验,结果表明：酿酒曲具有提高果汁出汁率,从而提高酒精度的作用;适当提高酿酒曲含量有利于果汁含糖量的快速降解,可获得较高浓度的酒精     

八轮四摆臂无人机动平台越障性能分析与试验

针对南方山区丘陵地带地形复杂、传统农田运输车辆通过性不足的问题,提出并设计了一种具有仿生液压驱动摆臂机构的八轮无人机动平台,其车体姿态可通过四摆臂协同动作进行调节,以适应不同形式地面障碍。越障性能是制约平台通过性的根本因素,建立了无人平台姿态规划模型和关键越障过程动力学模型,得到无人平台在典型垂直障碍的越障性能。为验证理论分析,在ADAMS建立了二次开发仿真平台,并进行了样机动力性试验。研究表明,八轮四摆臂无人机动平台可攀爬高度为轮胎直径1. 13倍的垂直障碍,具有良好的复杂地面环境通过能力,可满足丘陵地带农用运输车辆在复杂农田地形的行走需求。     

楼房式肉食综合体智能管理系统

为确定肉食综合体项目现实意义,分析了河南省南阳市内乡县楼房式肉食综合体工艺设计及其生产流程,结果表明内乡县畜牧经济已实现由要素驱动型增长向经济创新型发展.内乡县肉食综合体的建设加强了内乡县经济发展要素保障,初步解决了内乡县区域经济发展瓶颈问题,确定了现代生猪产业发展的新走向.     

Early flower initiation allows ample manipulation of flowering time in cherimoya (Annona cherimola Mill.)

Flower initiation date and readiness to flowering in buds of different age were studied in ‘Fino de Jete’ cherimoya (Annona cherimola) cultivar in order to establish the limits for the manipulation of its flowering date. Flower initiation was analyzed by light and scanning electron microscopy (SEM) collecting axillary buds from May to the following February, whereas the bud readiness to produce perfect flowers was determined by forcing buds of different age to sprout by means of leaf removal and tipping the new growth. SEM images confirm that cherimoya buds are differentiated into flowers almost a year before blooming. In this regard, axillary buds have already formed the sepals when the subtending leaf has just begun unfolding (week 0), while the petals are clearly visible in 1-week-old buds. Sectioning of paraffin-embedded buds illustrate that cherimoya buds are in fact a bud complex that 1 week after its inception comprises 4–5 buds of different size of which the two largest ones are reproductive, while the 2–3 smallest buds often remain undifferentiated at that time. The high capacity of flowering expressed by young buds that have been forced to grow proves that cherimoya meristems are early competent for flowering. No differences in fertility or in the time needed to reach anthesis after leaf removal were found among buds of different ages. Node position had no effect on bud break and flowering potential. The early flower initiation in cherimoya deduced from this work opens a wide temporal window for the experimental manipulation of flowering and harvest dates in this crop.     

复杂注水系统泵站优化调度的改进遗传算法

以耗电量最小为目标函数,排量、压力等限制为约束条件,建立了复杂注水系统泵站优化调度数学模型.针对系统运行特点,采用改进遗传算法对模型进行求解,同时优化出泵的运行状态和排量.改进遗传算法采用实数编码,并设计了随机多父辈交叉方法,改进了变异操作,操作过程中,给出了泵排量的处理方法,使各水量约束条件得到满足,大大减少了不可行解的产生,使算法的优化性能得到了提高.算例说明了该优化方法的有效性.     

Research on immunization strategies based on independent sets of complex networks

According to the concept of independent set, this paper proposes a new immunization strategy of complex networks which immunizes the nodes in an independent set with maximum degree, called targeted immunization in the independent set. When the total degree of immune nodes in independent set is equal to the total degree of targeted immunization nodes in the whole network, the immunization strategy of independent set is more effective than the targeted immunization strategy of the whole network. Based on the network structure, this paper explains the reason. Comparing the random immunization of independent sets with the random immunization in the whole network, test results indicate that more nodes do not be removed with high degree for the random immunization of independent sets. For classic susceptible-infected(SI) model, all nodes in the network are only two states: susceptible or infected. In the study of immunization strategies, comparing SI model with SIR, SIS models. The use of SI model will be more favorable.