奥-贝球铁焊接HAZ组织性能与断口分析

利用Ｇｌｅｅｂｌｅ－１５００焊接热模拟试验机,通过改变峰值温度Ｔｍ、高温停留时间ｔｍ和冷却速度ｔ８／５,研究了奥－贝球铁焊接ＨＡＺ力学性能和断口形貌。当Ｔｍ增加时,强度σｂ下降,断口由准解理断裂形貌过渡到脆断形貌;在ｔｍ增加时,强度σｂ缓降,断口脆断逐渐明显;而当ｔ８／５增加时,强度σｂ增加,在ｔ８／５＝４０ｓ达到最高值,当进一步增加ｔ８／５,强度σｂ略有下降,断口表现为珠光体组织中铁素体与渗碳体分开特征,并证明奥氏体区是ＡＤＩ焊接接头力学性能最薄弱的区域。     

贺兰山野生大型真菌孢子多样性分析

为探讨贺兰山野生大型真菌孢子的多样性,2012-2016年在内蒙古贺兰山南寺和哈拉乌沟两地进行取样,每个样地分别由5人从沟谷入口处进行拉网式调查,共获得4 000余份样品,经过微观形态观察和基因ITS序列比对,鉴定出8目25科69属189种大型真菌,主要对其孢子形态特征、表面特征及长宽比进行分析,得到如下结论:质量性状上,孢子形态特征和表面特征相互独立;数量性状上,大小孢子长宽比、孢子极端比和平均比均具有一致性和关联性,显示孢子数量特征的稳定性;菌种间孢子质量性状和数量性状具有很强的多样性;按照孢子多样性低、中、高分类,贺兰山野生大型真菌物种数分别为152种、26种和11种;孢子多样性分类为大型真菌鉴别、分类提供了基本依据。     

短穗兔耳草的克隆生长特征

以调查统计的方法研究了高寒草甸匍匐茎植物短穗兔耳草Lagotis brachystachya无性系的生长特征、形态特征以及能量分配规律,研究结果表明:匍匐茎只有1条的短穗兔耳草最多,占60．47％,匍匐茎有4条的短穗兔耳草只占6．98％。在牧草生长盛期,短穗兔耳草无性系的基株高度4．03 cm,根长为9．11 cm,叶数为7．98;分株高度0．85 cm,根长2．73 cm,叶数为3．08;匍匐茎的茎生叶数为12．54,长度为15.14 cm,匍匐茎比节间重为2．18 mg／cm,粗度为0．97 mm,不同构件的干质量呈现出基株>匍匐茎>分株>茎生叶的规律。随着匍匐茎数目的增多,短穗兔耳萆无性系的基株根长逐渐增加,用于克隆繁殖的能量投资也有增加的趋势,其他参数都没有明显的变化规律。     

白虎汤对鸡毒支原体体外抑制作用及其超微结构的影响

目的:观察鸡毒支原体(MGPG31)形态和超微结构变化,探讨白虎汤体外对MGPG31抑制作用的机理。方法:(1)用二倍稀释法测定白虎汤对MGPG31的MIC;(2)在MIC(0.094g/ml)和亚MIC(0.0235g/ml)的条件下取白虎汤与鸡毒支原体培养48h后的样品,通过透射电镜观察支原体的形态和超微结构变化。结果:白虎汤对鸡毒支原体的MIC1和MIC2分别为0.047g/ml和0.094g/ml。白虎汤主要作用于繁殖期支原体,影响细胞膜通透性和形态而起到抑制作用。     

中国甘肃东北部地区东方蜜蜂(Apis cerana)形态学研究

本研究采集甘肃东北部地区泾川蜂场、庄浪蜂场和平凉蜂场的东方蜜蜂Apis cerana43群,采样点地貌包括山地、丘陵和平原。运用蜜蜂形态学研究方法对东方蜜蜂40个形态特征指标进行测量分析。运用SPSS13.0对蜜蜂形态数据进行方差分析、主成分分析、聚类分析及环境因子相关性分析。研究结果表明:甘肃东北部地区不同采样点东方蜜蜂形态特征指标存在显著差异,而且与环境因素显著相关。     

紫花针茅生殖器官形态的变异及其与环境因子的关系

紫花针茅(Stipa purpurea)是青藏高原分布面积最广的植物之一,对高原环境具有广泛的适应性。该植物具有的锥形繁殖体(包括种子和附属结构),是其适应环境的主要特征之一。为揭示该植物对高原环境的适应性表现,本研究对不同纬度的20个紫花针茅种群繁殖体的形态特征及其与环境的关系进行比较研究。结果表明,1)种长的变化幅度为0.692~1.255 cm,种宽的变化幅度为0.392~0.713 mm,芒长的变化幅度为2.394~8.736cm,种子重的变化幅度为0.678~1.560 mg。芒长和种子重具有较高的种群间变异系数。种子重与种长呈极显著正相关关系(P0.01),和芒长呈显著正相关关系(P0.05);种长、种宽、芒长相互之间均呈极显著正相关关系。2)种长、种子重与等效纬度均呈显著正相关关系,与年均降水量均呈显著负相关关系;种长与年均温呈现出凸型变异的关系。3)20个种群依据繁殖体特征进行聚类分析可分为3组,聚类结果与地理分布基本一致。     

五种西方蜜蜂品种形态指标差异性比较

采集吉林的东北黑蜂×意蜂、云南景洪的浙大蜜浆蜜胶、云南景洪的白山6号、云南个旧蛮耗的本地王和云南蒙自草坝的浙大蜜浆高产5种西方蜜蜂子代工蜂共8群样本,每群测定分析15只,测定每只工蜂38个形态指标。结果表明不同生产性能的西方蜜蜂在形态特征上都表现出差异性(P≤0.01,或0.01P≤0.05,或P0.05),通过实验,为蜜蜂生产上培育杂种优势西方蜜蜂品种提供有力的理论依据。     

6种枇杷属植物花粉形态扫描电镜观察

应用扫描电镜,对1个栽培品种(早钟6号),5个野生类型(椭圆枇杷、大渡河枇杷、栎叶枇杷、台湾枇杷、台湾枇杷恒春变型)的花粉进行了形态观察。结果表明,6种枇杷属植物的花粉粒均为长球形,具3条萌发沟,萌发沟以等间距环状分布,属于N3P4C5型花粉。6种枇杷属植物的花粉外壁属于条纹-穴状纹饰类型,外壁均具条嵴,嵴洼处散生有覆盖层穿孔,但条嵴及穿孔的形态和分布差异明显。最后,结合花粉形态的演化规律,对大渡河枇杷的系统学位置及枇杷属植物的起源与进化进行了讨论。     

The canine T wave: a retrospective analysis on qualitative and quantitative T wave variables obtained in 129 healthy dogs and proposed reference intervals

Introduction/objectiveThe T wave is a poorly characterized electrocardiographic variable in small animals. Therefore, this study aimed to describe T wave features in a large population of healthy dogs.Animals, materials, and methodsMedical records were reviewed to identify healthy dogs ≥one-year-olds that underwent an electrocardiogram. T wave qualitative (morphology, polarity, and concordance between R and T waves) and quantitative (duration, amplitude, mean electrical axis, ratio between T and R waves amplitudes, interval from the peak to the end of the T wave, and ratio between the duration of the latter interval and that of the QT) variables were evaluated. Continuous and categorical variables were compared between dogs of distinct sex, body weight (BW), age and somatotype using the Mann–Whitney U test and χ² test, respectively. Spearman's correlation coefficients between quantitative variables and age and BW were calculated. Reference intervals of quantitative variables were determined in the overall population.ResultsOne hundred and twenty-nine dogs were enrolled. Concerning morphology, the asymmetrical (slow/fast) pattern occurred more frequently than the symmetrical and biphasic ones. Concerning polarity, positive T waves occurred more frequently than negative and neutral ones. T and R waves were predominantly concordant. No meaningful differences were found when comparing qualitative and quantitative variables between dogs of distinct sex, BW, age and somatotype. No significant correlations were found between quantitative variables and age and BW. Reference intervals of quantitative variables are provided.ConclusionsCanine T wave features were addressed and statistically reliable reference intervals made available for clinical use.