甘蔗逆剥剥叶方式的试验研究

传统离心撞击式剥叶装置采用根部喂入、剥叶辊筒与输入输出辊筒转向相同的剥叶方式,普遍存在着含杂率偏高、无法实现断尾的问题。为此,通过设计的甘蔗剥叶试验台进行了甘蔗尾部喂入、剥叶辊逆剥剥叶方式的试验研究,探索其剥叶效果,并分析了逆剥的剥叶和断尾机理。试验结果显示,逆剥方式在输入输出辊转速254 r/min,第1级剥叶辊(顺剥辊)转速1 152 r/min,第2级剥叶辊(逆剥辊)转速1 152 r/min时含杂率达到最低值0.7%,而断尾率达到100%。与顺剥方式进行对比试验,逆剥效果优势显著。     

Induction of apoptosis by three marine algae through generation of reactive oxygen species in human leukemic cell lines

In this study, we examined the antitumor effect of marine algae extracts on human hepatoma and leukemia cells. Ethyl acetate extracts from Colpomenia sinuosa (Cs-EA), Halimeda discoidae (Hd-EA), and Galaxaura oblongata (Go-EA) directly inhibited the growth of human hepatoma HuH-7 cells and leukemia U937 and HL-60 cells in a time- and dose-dependent manner. Specifically, these algae extracts induced apoptosis of U937 and HL-60 cells as evaluated by detection of hypodiploid cells using flow cytometry and observation of condensed and fragmented nuclei in algae extract-treated cells. Intracellular reactive oxygen species (ROS), especially hydrogen peroxide and superoxide anion, were increased about 2-3-fold in U937 cells treated with Cs-EA for 3-5 h. Interestingly, antioxidant N-acetylcysteine effectively blocked Cs-EA-, Hd-EA-, and Go-EA-induced apoptosis, suggesting that ROS is a key mediator in the apoptotic signaling pathway. In conclusion, our results show that algae extracts induce apoptosis in human leukemia cells through generation of ROS.     

西南山区村域贫困家庭劳动力转移强度空间格局及影响因素

贫困山区劳动力转移就业是提高家庭收入和实现脱贫的重要途径,但也造成了农村人才资源流失、社会经济建设缓慢甚至衰退等问题。科学揭示贫困家庭劳动力转移强度空间分异机制,对实施精准扶贫和乡村振兴战略具有重要的现实意义。该文以重庆长寿区为案例区,运用综合评价法对村域贫困家庭劳动力转移强度进行测度,并结合地理探测器、OLS模型等方法,探测出劳动力转移强度地域分异的主导因素,揭示空间分异机制,从而探究乡村发展策略。结果表明:村域贫困家庭劳动力转移强度空间分布具有明显的地域差异性,表现出"两高一低"的空间分布特征,西部明月山区和东南黄草山区高,西南-中部低丘区低,整体呈现北部高,南部低的趋势;影响劳动力转移强度空间分异的主导因素是人口老龄化、人均耕地资源、地面坡度、劳动技能培训,各因素对劳动转移强度分异决定力值分别为0.410、0.396、0.363、0.301;劳动力转移强度是多种因素相互作用的结果,且任何2个因素的交互作用大于单个因素的作用;基于村域贫困家庭劳动力转移分异机制,不同强度区域应因地制宜,从空间、经济、社会等方面制定不同的发展策略,为有序推进精准扶贫实现稳定脱贫和乡村振兴战略提供科学参考。     

A universal HPLC method for the determination of phenolic acids in compound herbal medicines

A universal method to separate and quantify 13 phenolic acids (gallic acid, chlorogenic acid, gentsic acid, vanillic acid, caffeic acid, syringic acid, sinapic acid, p-coumaric acid, ferulic acid, anisic acid, rosmarinic acid, salicylic acid, and cinnamic acid) in some compound herbal medicines was established by liquid chromatographic (HPLC). On an Agela XBP-C18 (5 microm, 4.6 mm x 150 mm) column, a multistep binary gradient elution program and a simplified sample pretreatment approach were used in the experiment. For all of the phenolic acids, detection limits ranged around 0.01 mg/L. Linear ranges of higher than 2 orders of magnitude were obtained with a correlation coefficient of 0.9991 to 1. Repeatability was 0.39-2.24% (relative standard deviation, RSD) for intraday, 1.17-3.96% (RSD) for interday, and 0.14-5.33% (RSD) for drug sample analysis. Recovery, tested by a standard addition method, ranged from 83.3% to 104.9% for various trace phenolic acids.     

云南作物生产潜力的海拔修正对耕地自然等别评价结果的影响

作物光温生产潜力(thermal potential productivity,TPP)、气候生产潜力(climatic potential productivity,CPP)是农用地质量分等技术体系中的重要参数,其客观性对分等结果的准确性有很大影响。在耕地分布海拔差异较大的区域,实际工作中以县级气象站点TPP、CPP代替全县域TPP、CPP的取值方式导致耕地质量评价结果的准确性不足。该文旨在通过对气象站点指定作物TPP、CPP进行海拔修正,获取陆良县气象站点以外区域的指定作物潜力值并探讨其对耕地自然质量等的影响。首先,以第1轮云南省农用地分等工作中陆良县归属的滇中高原盆地区56个县级气象站点指定作物的TPP、CPP为基础,生成区域内一季稻、夏玉米、冬小麦TPP、CPP的海拔修正模型;其次,在陆良县县域范围内,每村各选取一块质量最好的旱地和水田,以样点旱地、样点水田作物实际单产验证模型的合理性;最后,验算陆良县范围内所有耕地采用修正后的TPP、CPP评定的自然质量等与采用修正前的TPP、CPP评定的自然质量等的差异。结果显示:各样点一季稻、夏玉米、冬小麦的实际单产均低于修正前和修正后的TPP、CPP,且与修正后的TPP、CPP随海拔的变化趋势一致;修正后的一季稻、夏玉米、冬小麦TPP、CPP较修正前更符合自然实际;全县修正后的耕地自然质量等较修正前变化范围为?0.8~1.7等,且99.76%的耕地自然质量等较修正前降低值在1.5等以内。     

苦丁茶树短穗扦插育苗技术的研究

不同季节，苦丁茶树插穗最适发根的土壤条件不尽相同，秋季扦插以Ａ１类土壤较好，夏季扦插以Ａ２类土壤较好，这时克服一年中不同季节发根快慢不一致等问题有重要意义．同一枝条中以中段插穗发根最快，插穗以留２叶并剪叶１１２～１／３为宜．母树树龄愈短，剪取的插穗愈易发根；同一植株上，自根颈部附近发出的枝条剪穗，其发根速度较自上部枝条剪穗的快，这为苦丁茶树“超短穗”扦插提供了理论依据．生根剂Ｂ２对插穗发根有显著的促进作用，但要注意使用的浓度和处理时间．     

蓝莓丛生芽的诱导及植株再生

利用蓝莓的茎段作为外植体,在添加各种激素的培养基上培养,研究蓝莓茎段离体繁殖影响因素,筛选出蓝莓离体最佳增殖和生根培养基及培养条件.结果表明:在MS 2mg/L ZT 0.2mg/L NAA的增殖培养基上,经过两次继代培养后蓝莓的增殖系数可达到30～50倍左右,在1/2 WPM 0.5 mg/L IBA的生根培养基上单株试管苗平均可产生7.5条根系,生根率可达到95%以上,通过炼苗和移栽试管苗的成活率可达95%左右,从而建立了蓝莓工厂化育苗技术体系,为蓝莓产业的发展提供了充足的优良种苗.     

作物染色体导入系的构建及其应用

染色体导入系,也称染色体片段代换系、回交重组自交系或近等基因系,是借助分子辅助选择方法,通过回交和自交,从供体中导入一个或几个小的染色体片段进入轮回亲本.相对于传统的遗传群体,导入系群体大大降低了供体材料的遗传背景的干扰,提高了QTL分析的灵敏度和准确性,是QTL鉴定、精细定位、互作分析、图位克隆、性状改良及杂种优势利用和基因表达分析的理想的实验材料.本文就染色体导入系的研究情况进行了详细的综述.     

DIGITAL SIMULATION OF HIGH VOLTAGE AC/DC PARALLEL SYSTEMS

The method of companion model is applied to the digital simulation of high voltage hybrid AC/DC systems for the first trme in this thesis.The mathematical model of the digital simulation of hybrid AC/DC systems is represented. This method can model the normal states, faults and games of faults of any hybrid AC/DC systems. The method has a series of advantages : saving the computation and the amounts of memory, high precision and fast calculation and it can be used with convenience. The simulation results of a hybrid AC/DC system arc in consistent with that of theoretical analysis. It shows that the mathematical model, the simulation method and the program in this thesis are correct.     

香果树组织培养技术研究

采用香果树幼树叶片作外植体,接种到附加不同浓度的KT和ZT组合的MS培养基上,诱导植株再生.结果表明,最适宜香果树叶片愈伤组织诱导和芽增殖的培养基是MS KT 1.0 ZT 2.0,愈伤组织诱导率达35.6%,芽增殖倍数为2.8倍;比较理想的生根培养基是1/2 MS IAA 0.5和1/2 MS IBA 0.5,生根率分别为65%和75%.试管苗移栽最理想的移栽基质是泥炭与珍珠岩(5∶1)的混合物,移栽成活率达95.2%.