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1.
甘蔗物流系统模型主要包括扶蔗、砍蔗、输送、剥叶等过程.每个部件之间能否协调运作,匹配是否合理,相互之间衔接和位置布局是否符合要求都是设计的关键.通过对甘蔗收获机械在收获过程中,甘蔗遍历的过程及各机构的运动原理,在基于全局协调理论的基础上,采用机械优化设计中迭代优化的方法,对各机构的运动参数和协调参数进行优化,达到甘蔗在收获过程中的最优的甘蔗收获机械物流系统模型.  相似文献   
2.
用黔糖4号作供试材料,选择蔗茎嫩梢部茎腋芽作接种外植体进行离体培养;外值体消毒采用75%酒精浸泡8~10s后用0.1%HgCl2消毒15min复合消毒,多次清洗再接种;腋芽诱导培养基采用(液态)1/2MS 0.25mg/L(6-BA);丛芽诱导增殖培养基采用(固态)MS 2.5mg/L(L-BA) 0.2mg/L(KT),每隔15~20d转基继代一次,繁殖倍数可达30倍以上;生根培养基采用(固态)1/2MS 3.0mg/L(NAA) 0.1mg/L(IBA),添加2.5mg/L的MET,使丛苗根粗苗壮;炼苗后移至“沙土沙”的苗床假植,再单株假植至20cm左右高的苗时进行大田定植;摸索总结了一套黔糖4号腋芽离体快繁种苗技术,并详细介绍了操作要领,提出了有关环节中应注意的五个问题和相应的解决方法。  相似文献   
3.
In this paper the author: (a) discusses the uniqueness of rattan among non-timber forest products, (b) examines the financial and the economic profitability of smallholder rattan cultivation, and (c) outlines a strategy for expanding smallholder rattan plantations among non-traditional producers.  相似文献   
4.
文中论述了棕榈藤各种藤材存在的主要缺陷,并计论了藤材的分级标准和工业用藤的规范。棕榈藤材的缺陷包括基因缺陷、环境缺陷、生物缺陷和机械缺陷等。棕榈藤材的定级基于不同阶段,分级的基本依据是藤茎直径、长度、颜色、硬度、缺陷、节间长度以及直径全长均匀性等。工业用藤的规范涉及:表观特性、物理力学特性、机械加工特性和涂饰性等。统一的缺陷术语、贸易名称和标准规范是良好贸易的基准。  相似文献   
5.
针对蔗梢在榨糖过程中会降低甘蔗的出糖率,以及蔗梢部分进入甘蔗收割机物流系统不利于物流系统的正常运转、堵塞物流通道等问题,在原有物理样机上加装切梢装置。通过对切梢装置运动要求的分析,设计了切梢装置的液压传动系统,并用AMESim软件对系统进行了建模仿真分析;同时,试验分析了切梢装置马达的动态特性,并得到马达在不同状态下的动态特性变化,验证了方案的可行性;最后,通过田间试验测试了切梢装置液压系统流量及压力的变化,并获得了其在田间实际工作时消耗的功率。  相似文献   
6.
J. C. Skinner 《Euphytica》1982,31(2):523-537
Summary The efficiency of family selection in bunch-planted sugareane seedlings was investigated by planting 40 families (20 proven and 20 experimental) as bunches and as single seedlings in adjoining replicated trials. A replicated trial planted the following year. using stem cuttings from random seedlings of each family. provided an independant estimate of the value of each family.Five methods were used to compare bunch and single planting, namely theoretical and realized gains from selection, correlations between the seedling and evaluation trials, discrimination based on proven cross classes, and discrimination based on production of advanced selections. Overall, bunch planting was inferior to single planting for family selection. It was promising for only one method of evaluation (proven cross classes) but this, combined with the relatively small area required for bunch-planted seedlings, indicates that family selection may be possible in such plantings. The use of a number of methods of evaluation showed that incorrect conclusions were likely if only one method were used, and revealed deficiencies in methods which would otherwise be considered satisfactory. The project provided a basis for the design of more critical experiments.The components of weight of cane, namely number of stalks and weight per stalk, are negatively correlated, and showed different relationships with yield in the seedling and evaluation trials. Weight per stalk was an important component in seedling trials, with number of stalks by far the main component in the evaluation trial which was planted by the commerical method using stem cuttings.Family selection based on number of stalks and sugar content, preceding mass selection, is likely to provide a better selection system than the usual mass selection in bunch-planted seedlings.Families do not express their full genetic potential in original seedlings. whether bunch or single planted: trials planted from stem cuttings give more effective family selection. Furthermore, family selection for the most important characters (net merit grade and weight of sugar) was much more effective in ratoon than in plant crops. These results have important implications for the practical selection program, further experimental work being necessary to specify the most efficient system.  相似文献   
7.
以甘蔗糖蜜为原料,发酵合成茁霉多糖发酵的初始条件。以生物量和多糖产量为依据,在确定以甘蔗糖蜜发酵合成茁霉多糖的初始发酵培养基的基础上,研究影响甘蔗糖蜜发酵合成茁霉多糖条件的因素。研究结果表明,以甘蔗糖蜜为原料发酵合成茁霉多糖的生物合成条件是:接种量为15%,发酵温度为30℃,在充足供氧条件下的发酵时间为144h。  相似文献   
8.
D. L. Jennings 《Euphytica》1982,31(3):953-956
Summary Gene H determines cane hairyness in raspberries and was reported to facilitate escape from infection by Botrytis cinerea and Didymella applanata. However, experiments with mycelial inoculations of wounded canes showed that it conferred a form of resistance which was evident for a long period after the establishment of infections by these pathogens. The gene also contributed to the resistance of fruit to B. cinerea and of canes to Leptosphaeria coniothyrium. Alternative hypotheses to explain these observations are discussed: two based upon its possible genetic linkage with a gene or genes for resistance and one based upon its possible pleiotropic effects.  相似文献   
9.
Seventeen diverse clones of sugarcane (Saccharum spp.) (7 early, 6 mid season and 4 late) were planted in October 1991 and 1992 in flooded (FE) and non flooded (NFE) environments for evaluation of cane yield, commercial cane sugar (CCS), internode length, internode number, stalk length, stalk thickness (circumference), stalk number, sugar recovery, and stalk weight. Cane yield showed significant positive phenotypic correlation coefficient (PCC) with stalk number in FE (P ≤ 0.05) and NFE (P ≤ 0.01). Stalk length had a significant positive PCC with stalk weight in both environments, and with internode length in FE (P ≤ 0.05). Commercial cane sugar also expressed significant positive PCC with cane yield in both environments (P ≤ 0.01), but with stalk number only in NFE (P ≤ 0.05). Genotypic correlation coefficients were generally in the same direction as PCC but higher in magnitude. In both environments, stalk number and stalk weight had relatively high positive direct effects on cane yield. However, flooding tended to enhance the direct effect of stalk weight and diminish the direct effect of stalk number on cane yield. Only cane yield and sugar recovery had high direct effects on CCS. Selection for improvement of cane yield can be based on stalk number and stalk weight in both environments. High yielding clones can be further screened for more sugar recovery to improve CCS. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
10.
葡萄结果母枝粗度与新梢结实力的关系   总被引:1,自引:0,他引:1  
研究了11个葡萄品种结果母枝粗度与新梢结实力的关系,结果表明,不同葡萄品种获得理想的新梢结实力,其结果母枝须有一适宜的粗度范围;结果母枝粗度与结果枝率、结果枝结果系数、新梢结果系数之间呈二次多项式回归关系;不同葡萄品种冬季修剪时结果母枝的选留应以不同粗度结果母枝的结实力为依据。  相似文献   
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