41％草甘膦异丙胺盐水剂防除北方苹果园杂草药效试验

41％草甘膦异丙胺盐水剂防除北方苹果园杂草药效试验结果表明,该药剂可有效防除北方苹果园的一生杂草及多年生杂草,且对果树安全,推荐使用剂量为1230-2460g a．i．／hm^2。于苹果园杂草旺盛生长期进行茎叶喷雾处理。     

微波辅助提取羊栖菜多酚的工艺研究

以羊栖菜为原料,在单因素试验的基础上,采用四因素三水平正交试验设计,优选微波辅助提取羊栖菜多酚的最佳工艺条件：乙醇体积分数80%,微波功率600 W,浸提温度70℃,料液比1∶10 g·mL-1,浸提时间4 min,此条件下羊栖菜多酚得率可达233%。     

猪李氏杆菌病的病原分离鉴定与药敏试验

为确诊发生脑膜炎的死亡仔猪病例,对病原进行了分离鉴定和筛选敏感药物试验。采用分离培养、染色镜检与纯培养、动物试验、生化试验等方法分离鉴定病原,并用纸片扩散法筛选敏感药物。试验结果表明,分离菌的生化特性、培养特性、溶血性等符合单核细胞增多性李氏杆菌的病原特性,确诊为猪李氏杆菌病;分离菌株对丁胺卡那霉素、头孢噻呋、万古霉素、四环素高度敏感;对土霉素、多黏菌素、磺胺类药物、新霉素耐药。     

基于灌区节水管理的孔口闸门设计研究

基于灌区末级灌溉工程供水、量测水配套建设的现状,提出一种适用于灌区节水管理需要且构思新颖的新型孔口闸门技术设施,围绕闸门启闭、流量观测、过闸流量调控3项技术集成所涉及的主体结构、配套设备、测流原理、材质选取、工艺流程等技术问题,进行了设计研究.     

Spatio-temporal variation of soil moisture in a fixed dune at the southern edge of the Gurbantunggut Desert in Xinjiang,China

Soil moisture is critical for vegetation growth in deserts. However, detailed dataregarding the soil moisture distribution in space and time in the Gurbantunggut Desert have not yet been reported. In this study, we conducted a series ofinsitu observation experiments in a fixed sand dune at the southern edge of the GurbantunggutDesert from February 2014 to October 2016, to explore the spatio-temporal variation of soil moisture content, investigate the impact of Haloxylonammodendron (C. A. Mey.) Bungeon soil moisture content in its root zone, and examine the factors influencing the soil moisture spatial pattern. One-way analysis of variance,least significant difference testsand correlation analysis were used to analyze the data. The results revealed that the soil moisture content exhibited annual periodicity and the temporal variation of soil moisture content throughout a year could be divided into three periods, namely, a moisture-gaining period, a moisture-losing period and a moisture-stable period.According to the temporal and spatial variability, the 0-400 cm soil profile could be divided into two layers: an active layer with moderate variability and a stable layer with weak variability.The temporal variability was larger than the spatial variability in the active layer,and the mean profile soil moisture content at different slope positions displayed the trend of decreasing with increasing relative heightand mainly followed the order of interdunearea>westand east slopes>slope top.The mean profile soil moisture content in the root zone of dead H. ammodendronindividuals was significantly higher than that in the root zones of adult and young individuals, while the soil moisture content in the root zone of adult individuals was slightly higher than that in the root zone of young individuals with no significant difference.The spatial pattern of soil moisture was attributable to the combined effects of snowfall, vegetation and soil texture, whereas the effects of rainfall and evaporation were not significant. The findings may offer a foundation for the management of sandy soil moisture and vegetation restoration in arid areas.     

福寿螺细胞色素P450 基因CYP3192A1 的克隆与表达分析

细胞色素P450酶 (Cytochrome P450, CYPs) 由P450基因编码,其中Cyp1a基因参与不同类型外源物质的生物转化和代谢。克隆了紫红笛鲷 (Lutjanus argentimaculatus) Cyp1a基因,对其组织表达模式进行分析,探讨了不同质量浓度 (10、50和250 μg·L⁻¹) 一溴联苯醚 (4-bromodiphenyl ether, BDE-3) 和十溴联苯醚 (decabromodiphenyl ether, BDE-209) 胁迫对紫红笛鲷肝脏Cyp1a表达及7-乙氧基香豆素-O-脱乙基酶 (7-ethoxyresorufin O-deethylase, EROD) 活性的影响。结果表明,紫红笛鲷Cyp1a cDNA全长2540 bp,开放阅读框长1 566 bp,编码521个氨基酸。同源分析结果表明紫红笛鲷CYP1A与花鲈 (Lateolabrax maculatus) CYP1A蛋白相似性最高 (92.69%),进化树分析与白梭吻鲈 (Sander lucioperca) 聚为一支,进化地位最近。Cyp1a基因在紫红笛鲷肝脏表达量最高,其次是脑和鳃,肌肉最低。10 μg·L⁻¹ BDE-3和BDE-209未对Cyp1a基因表达和EROD活性产生影响,而50和250 μg·L⁻¹BDE-3胁迫7~15 d则对两者产生显著抑制,且呈现剂量效应。与BDE-3相反,50和250 μg·L⁻¹ BDE-209 处理组Cyp1a基因表达和EROD活性显著增加,且Cyp1a基因表达与EROD活性呈显著正相关。高浓度BDE-3和BDE-209可对紫红笛鲷肝脏Cyp1a基因的表达产生影响,但两者的影响模式不同。     

含1,2,4-三唑基和肟醚基的N-甲氧基氨基甲酸酯类化合物的合成及杀菌活性

通过(Z)-1-(取代苯基)-2-(1H-1,2,4-三唑-1-基)乙酮肟与N-甲氧基-N-(2-溴甲基苯基)氨基甲酸甲酯反应,合成了11个新的含有三唑基和肟醚基的N-甲氧基氨基甲酸酯类化合物( V1 ~ V11 ),其结构均经1H NMR、IR、LC/MS及元素分析确证。对合成的化合物进行了离体抑菌活性实验,结果表明:在50 mg/L下,所有化合物对小麦赤霉病菌Gibberella zeae (Schw.)Petch、稻瘟病菌Pyricularia oryzae Cav.和黄瓜灰霉病菌Botrytis cinerea Pers.都有一定的抑菌活性,其中 V4 、 V11 对稻瘟病菌的抑菌活性分别达96.5%和96.7%,对黄瓜灰霉病菌的抑菌活性分别达到95.9%和90%。     

南瓜糕的研制

研究了南瓜糕适宜的配方和生产工艺条件,并对产品的质量及卫生指标进行检测。结果表明:南瓜浆料的颗粒直径小于100μm,才能得到组织细腻的南瓜糕。pH为3.0时南瓜糕的凝胶效果较好。无糖南瓜糕的配制中最佳配方为:南瓜浆料∶木糖醇∶卡拉胶的比例为60∶40∶1;含糖南瓜糕的最佳配方为:南瓜浆料∶蔗糖∶卡拉胶比例为70∶15∶7.5。浓缩终点一般是可溶性固形物含量达到45%。最终得到的产品具有南瓜糕正常的色泽、气味和滋味,无异味,理化指标和微生物指标也符合相应国家标准。     

不同播量拉巴豆与青贮玉米混播对草地生产性能及牧草品质的影响

为探究宁夏雨养区不同播量拉巴豆(Dolichos lablab)与青贮玉米(Zeamays)混播对草地生产性能和牧草品质的影响,本试验采用随机区组设计,以不同播量(0 kg·hm-2,22.5 kg·hm-2,45.0 kg·hm-2,67.5 kg·hm-2,90.0 kg·hm-2)的拉巴豆与青贮玉米混播,并运用灰...     

四川老鹰茶醇提物的抑菌及抗氧化活性研究

以四川3个不同地区的老鹰茶及老鹰茶植物的鲜叶为原料,采用超声波辅助提取技术提取醇提物,测定多酚和黄酮含量以及抑菌和抗氧化性活性.结果表明:6种样品醇提物的提取率最高的为石棉老鹰茶鲜叶,为(26.73±0.68)％;总多酚和总黄酮含量最高的是石棉老鹰茶鲜叶,分别为(22.10±0.11)％和(16.77±0.14)％.6种样品醇提物对4种细菌均有抑制作用,且提取物浓度越高抑菌效果越强;其中石棉老鹰茶鲜叶对痢疾志贺氏菌(Shigella dysenteriae)抑制效果最好,抑菌圈直径达到(2.56±0.09)cm.6种样品醇提物的DPPH(1,1-二苯基-2-三硝基苯肼)自由基清除能力和总还原能力均高于对照品BHT(2,6-二叔丁基对甲酚).6种样品抑菌和抗氧化能力结果由强到弱为石棉老鹰茶鲜叶>叙州老鹰茶鲜叶>青川老鹰茶鲜叶>石棉老鹰茶>叙州老鹰茶>青川老鹰茶.试验表明四川3个不同地区的老鹰茶及老鹰茶植物的鲜叶均具有较强的抑菌和抗氧化活性,其中石棉老鹰茶植物的鲜叶相对更好,可优先开发利用.