越橘叶片转录组SSR发掘及其多态性研究

对高丛越橘品种‘布里吉塔’叶片转录组序列进行了简单重复序列（SSR）位点搜索和分析,发现了22 058个SSR位点,总发生频率为21.32%。SSR重复类型以二核苷酸发生频率最高（77.70%）,三核苷酸次之（21.45%）。选用53对SSR引物在8个越橘属植物中进行PCR扩增,筛选出15对条带清晰且能稳定扩增的SSR核心引物。使用核心引物对39份越橘属种质进行分析,有效等位基因数最大值为7.11（VcSSR19）,最小值为1.41（VcSSR41）,平均值为3.90。香农多样性指数变化范围是0.64 ~ 2.31,平均值为1.55。观察杂合度和期望杂合度的变化范围分别是0.050 ~ 0.900和0.293 ~ 0.870,平均值分别为0.457和0.677。使用5对引物可以完全区分39份种质中的38份。南高丛越橘品种‘莱格西’和‘蓝雨’与蔓越橘品种、越橘属野生种具有更近的亲缘关系,是与野生种进行杂交育种的合适种质。     

Preparation of Woody Activated Carbon for Supercapacitor Electrode by Steam Activation北大核心CSCD

In order to prepare activated carbons for supercapacitor electrode with low price and good performance, traditional steam activation method was employed to prepare activated carbons from masson pine wood. The elemental analyzer and the nitrogen adsorption/desorption were employed to analyze the element contents and pore structure of the activated carbons. The electrochemical performance of the activated carbon electrodes was examined by the methods including cyclic voltammetry, galvanostatic charge-discharge cycles and electrochemical impedance spectroscopy using 1-ethyl-3-methyl imidazole tetrafluoroborate/acetonitrile (EMIMBF4/AN) as electrolytes. The effects of activation temperature and time on the electrochemical performance of activated carbon were investigated. The results showed that the specific copacitance of activated carbon increased first and then decreased with the increment of activation temperature and activation time. The activated carbon prepared at carbonization temperature 900 ℃ and activation temperature 900 ℃ for 1 h reached the maximum of the specific capacitance. Its specific capacitance reached 155 F/g with a sweep speed of 5 mV/s and remaind 105 F/g at 100 mV/s, and the energy density in organic electrolyte was as high as 33.6 (W•h)/kg. After 5 000 cycles, specific capacitance was remain at value of 89 %. © 2018, Editorial Board of «Chemistry and Industry of Forest Products». All right reserved.     

琼脂-牛乳蛋白酸凝胶微流变特征研究

琼脂是酸奶常用稳定剂,适量添加可以有效提高酸奶的黏稠度,改善质地,防止乳清析出。研究了不同质量分数(0.025%~0.5%)琼脂对乳蛋白酸凝胶体系的微流变特性及凝胶动力学的影响,发现在恒温发酵阶段,琼脂对脱脂乳酸凝胶没有显著影响,在形成凝胶网络前,琼脂-脱脂乳混合体系的黏性因子(MVI)高于脱脂乳混合体系,在凝胶网络结构形成后,二者MVI值无显著性差异;随着发酵时间的延长,琼脂-脱脂乳混合凝胶晶格尺寸急剧减小。在冷却后熟阶段,随着琼脂浓度的增加,酸奶弹性因子增加,但是MVI值无显著差异。通过对琼脂-脱脂乳混合酸凝胶形成过程的动力学方程分析,确定了酸奶中适宜的琼脂浓度。该研究采用微流变动力学方法揭示了琼脂酸奶凝胶的流变学特性与变化规律,为指导企业酸奶生产提供了参考。     

盐胁迫下巴西蕉幼苗CaM含量的变化

研究巴西蕉幼苗在60 mmol/L Na Cl人工模拟的盐胁迫0、4、8、12、24和48 h不同时间下,通过增加外源CaCl_2和钙离子螯合剂EGTA处理后,测定其叶片和根的钙调蛋白(CaM)含量的变化。结果表明,与对照处理相比,在NaCl胁迫过程中,叶片CaM含量在4、8、12 h显著增加而在24和48 h显著减少;根的CaM含量则是在4、12、24 h显著增加,在8 h显著降低。在NaCl胁迫中添加CaCl_2处理能显著提高CaM含量,而在NaCl胁迫中添加EGTA处理能显著降低CaM含量。以上说明,通过CaM的含量变化,钙信号系统参与香蕉的耐盐调控。     

EGCG与杨梅素相互作用对茶汤色泽呈现的影响

【目的】探究EGCG(表没食子儿茶素没食子酸酯)与杨梅素的相互作用对绿茶茶汤色泽呈现的影响。【方法】以茶叶中主要的多酚类物质EGCG和杨梅素作为研究对象,将单独的EGCG、杨梅素以及EGCG与杨梅素混合母液分别溶于pH 5.0磷酸缓冲液,在100℃水浴中热处理10h,观察其颜色变化,采用色差仪、紫外分光光度计检测3种溶液的颜色变化规律,并根据溶液的色度值结合动力学方程,建立3种溶液颜色变化的动力学模型。【结果】光谱及色度变化结果显示:EGCG与杨梅素混合母液的色泽变化较其单独母液明显,从淡黄色变成红色;EGCG与杨梅素的相互作用能加深色度的变化,且两者均对混合母液的黄变、红变起作用。互作试验表明,杨梅素能加速EGCG黄变、红变的趋势,EGCG对杨梅素色泽变化有辅助作用。结合颜色动力学分析结果表明,在色泽变化中杨梅素对混合母液的红变起到主要作用,EGCG对混合母液的黄变起到主要作用。【结论】EGCG与杨梅素对色泽变化存在互作效应。     

非目的语环境下汉语教学实践与策略研究

海外汉语教师在教学中过度关注汉语口语教学,忽视其他技能训练,并且使用英语直接讲课,会影响学生学习汉语的兴趣。上述汉语教学问题导致阿联酋扎耶德大学汉语课堂教学效率低和学生流失严重。在行动研究理论的指导下,采取一门汉语综合课统摄听、说、读、写四项技能训练课的教学方式,并在提高汉语课堂教学效率方面提出三种教学策略。四个学期的效果追踪表明,在扎耶德大学零起点汉语班可以使用汉语讲课,一门汉语综合课统摄四项技能训练课的教学方式对学生坚持学习汉语取得了良好的效果。     

宁夏同心县一起羊炭疽疫情的暴发调查

2016年5月,宁夏回族自治区同心县某养殖户饲养的羊只发生炭疽疫情。通过现场调查、入户访谈、实验室检测等方法,对该起羊炭疽疫情进行了调查。结果发现,此次疫情共有4只羊发病死亡,均来源于同一养殖户。调查认为,该疫情可能由附近其他养殖户在山坡私埋病死羊引起,发病羊只采食被炭疽杆菌污染的牧草或直接接触私埋病死羊而感染,未追溯到私埋羊只的来源。单因素分析显示,在私埋点附近放牧羊只的发病风险是未在该区域放牧羊只的1.14倍(P=0.01),统计学意义显著。     

野生欧洲李种子萌发特性

为了掌握野生欧洲李种子萌发特性,探讨野生欧洲李实生繁殖规律,以新疆野生欧洲李为研究对象,观察种子形态,测定种子千粒质量、种皮透水性、种子含水量、种子活力,测定种子浸提液对白菜种子发芽和胚根生长抑制活性的影响。结果表明:新疆野生欧洲李种子的种皮透水性比较差;种子含水量为30.57%;TTC法检测种子活力为81.67%;4℃低温沙藏层积的野生欧洲李种子,在处理后90 d种子出现萌发,持续层积200 d后总萌发率为47%;种子各部分浸提液对白菜种子发芽率作用不明显,但对胚根生长有明显的抑制作用,随着浸提液浓度增长,对白菜种子发芽抑制活性越强,其胚根长度越短;随着野生欧洲李层积天数的增加,浸提液处理的白菜种子胚根长度增加;野生欧洲李种子各部分浸提物对白菜种子发芽抑制活性顺序为:种胚最强,种皮次之,种壳最弱。     

Fermentation quality and nutritive value of total mixed ration silages based on desert wormwood (Artemisia desertorum Spreng.) combining with early stage corn

This study aimed to investigate the fermentation quality and nutritive value of total mixed ration (TMR) silages based on desert wormwood (DW) combined with early stage corn (ESC) as forage and determine an optimum formula. Desert wormwood and ESC were harvested, chopped, and mixed with other ingredients according to a formula, packed into laboratory silos at densities of 500–550 g/L, and stored in the dark for 60 days. The DW proportions in the forage of TMR were 1, 0.75, 0.50, 0.25 and 0, based on fresh weight. As the proportion of DW decreased, the pH also decreased (P < 0.05), while lactic acid, lactic acid/acetic acid, crude protein, starch, and the in vitro digestibility of dry matter and neutral detergent fiber increased (P < 0.05). Ammonia nitrogen/total nitrogen in the TMR silages with DW proportions of 0.75, 0.25 and 0 in the forage was more than 10%. These results indicated that the quality of the TMR silage containing DW alone as forage was poor, TMR silages containing DW proportions of 0.75 and 0.25, and ESC alone, in the forage were not well preserved. The optimum TMR silage formula contained a DW proportion of 0.5 in the forage.