文化差异与英语教学

英语教学应重视我们同英语国家社会文化差异的研究。在特定的场合使用恰当的语言,首先必须了解对方的语言交际习惯和标准。     

T-RFLP技术及其在动物胃肠道微生物群落多样性研究中的应用

随着分子生物学技术的飞速发展,越来越多的新兴研究手段应用于胃肠道微生态系统的研究之中。介绍了末端限制性片段长度多态性技术(T-RFLP)的基本原理、操作流程和优缺点,并总结了该技术在动物胃肠道微生态研究中的应用现状。     

工程项目时间-成本均衡遗传算法终止条件的确定

研究了工程项目时间-成本均衡遗传算法的终止条件问题，并加以实证分析。在给定终止条件的基础上，有效地完善了工程项目时间-成本均衡遗传算法的算法步骤，结合实例来进行分析。成功地实现了算例结果。证实了工程项目时间-成本均衡遗传算法的有效性。     

牡丹顶芽组织培养的初步研究

以牡丹顶芽为试材,研究了不同时间0.1%HgCl2处理对顶芽污染率、褐化率及存活率的影响,并探讨了以MS为基本培养基,添加不同植物生长调节剂对牡丹顶芽的萌动、丛生芽的诱导以及生根的影响。结果表明:用0.1%HgCl2处理牡丹顶芽时,以处理8min左右为宜;顶芽萌动和丛生芽诱导最佳的培养基均为MS+Ca2++6-BA 2.5mg/L+NAA 0.5mg/L。该试验中所用的生根培养基在50d时,生根率达18%,生根效果不好,对此还需进一步研究。     

Improving the Productivity of Bread Wheat by Good Management Practices under Terminal Drought

Drought‐induced damages in crop plants are ranked at top amid all losses instigated by diverse abiotic stresses. Terminal drought (drought at reproductive phase) has emerged as a severe threat to the productivity of wheat crop. Different seed enhancement techniques, genotypes and distribution of crop plants in different spacings have been explored individually to mitigate these losses; however, their interaction has rarely been tested in improving drought resistance in wheat. This study was conducted to evaluate the potential role of different seed enhancement techniques and row spacings in mitigating the adversities of terminal drought in two wheat cultivars during two consecutive growing seasons of 2010–2011 and 2011–2012. Seeds of wheat cultivars Lasani‐2008 (medium statured) and Triple Dwarf‐1 (dwarf height) soaked in water (hydropriming) or CaCl₂ (osmopriming) were sown in 20‐, 25‐ and 30‐cm spaced rows; just before heading, the soil moisture was maintained at 100 % field capacity (well watered) or 50 % field capacity (terminal drought) till maturity. Terminal drought significantly reduced the yield and related traits compared with well‐watered crop; however, osmopriming improved the crop performance under terminal drought. Among different row spacings, wheat sown in 20‐cm spaced rows performed better during both years of study. Wheat cultivar Lasani‐2008 performed better than cultivar Triple Dwarf‐1 under both well‐watered and stress conditions. Maximum net returns and benefit–cost ratio were recorded from osmoprimed seeds of cultivar Lasani‐2008 sown in 20‐cm spaced rows under well‐watered condition. Nonetheless, osmoprimed seeds of cultivar Lasani‐2008 sown in 20‐cm spaced rows were better able to produce good yield under terminal drought.     

整合资源统一对T1和T2航站楼进行供冷和供暖

分析了目前武汉天河机场T1和T2两个航站楼供冷和供暖各自为阵的不利情况,提出了科学的改造方案,并对改造方案的可行性、改造后的优点、改造后的节能降耗情况进行了归纳和总结。     

松材线虫雌虫尾部形态和寄主的关系

Tenninal mucro of adult female was the distinct character between Bursaphelenchus xylophilus (Bx) and its allied species Bursaphe/enchus mucronatus (Bb). In general, Bx had no mucro. But it could have mucro in some situations. In the test, Bx without mucro was inoculated on Chineses pine (Pinus tabulaeformis) and Japanese black pine (Pinus thunbergii). The results showed that 85% of adult females Bx isolated from Chinese pine had terminal mucro. On Japanese black pine only 4.2% of adult females Bx had terminal mucro. Bx with terminal mucro from Chinese pine was re-inoculated on the fungus, Pestalotia sp. and Japanese black pine. It was found that 100% adult females had no terminal mucro on the fungus and 3.4% with terminal mucro on Japanese black pine.     

除草机器人自适应快速积分终端滑模跟踪控制技术

智能除草机器人在草坪作业时,易受到外界扰动以及系统不确定性的影响,从而导致轨迹跟踪收敛时间长以及跟踪效果差等问题。因此,设计一种面向轨迹跟踪的自适应快速积分终端滑模控制算法。首先,考虑驱动轮动力学特性以及未建模误差、外界干扰、动静摩擦等不确定性因素,建立除草机器人的动力学模型。然后基于所建立的动力学模型,设计自适应快速积分终端滑模控制器。所提出的控制器结合了快速终端滑模、积分滑模和自适应估计技术的优点,能够实现期望的跟踪性能并抑制控制信号抖动。同时,在不需要明确系统不确定性和外界干扰上界的情况下,可以通过所设计自适应估计项进行实时补偿,提高系统的鲁棒性。最后,通过仿真和试验验证了该方法的有效性。试验结果表明,所设计的控制器能够使跟踪误差在有限时间内快速收敛,并且横向误差绝对值不超过0.097 9 m,纵向误差绝对值不超过0.102 6 m,航向角误差绝对值不超过0.057 8 rad,保证除草机器人准确跟踪作业路径,同时具有较强的鲁棒性。     

麒麟菇菌糠在双孢蘑菇原种生产中的应用

以不同比例的麒麟菇菌糠配合棉籽壳、牛粪等基质进行双孢蘑菇原种培养基配方筛选试验。结果表明:菌糠是蘑菇原种生产的好材料,菌糠∶棉籽壳∶牛粪为58∶20∶20、38∶40∶20、48∶40∶10的配比比较适合双孢蘑菇菌丝生长,其中菌糠∶棉籽壳∶牛粪为58∶20∶20时表现最好。     

1年生泡桐不同部位顶芽内源激素的动态变化

在河南省郑州市以1年生毛白33泡桐为试验材料,利用间接酶联免疫吸附测定法(ELISA)测定梢枝顶芽、上部侧枝、中部侧枝和下部侧枝的顶芽内源激素含量动态变化。结果表明:1)梢枝顶芽、上部侧枝顶芽、中部侧枝顶芽及下部侧枝顶芽IAA的变化趋势一致,变化趋势为"降低-升高-降低",只是上部侧枝顶芽IAA升高后降低的趋势可能会推迟;2)梢枝顶芽、上部侧枝顶芽和下部侧枝顶芽GA3含量变化趋势基本相同,均呈现出"上升-下降-上升-下降"的"双峰"形;而中部侧枝顶芽GA3含量呈现出"下降-上升-下降"的趋势;3)不同部位顶芽ABA含量均是先升高,之后下降,最后在较低水平上趋于稳定状态;4)泡桐不同部位顶芽ZR含量随时间的变化呈现出不同趋势,但总体呈下降趋势,且不同部位顶芽间存在着竞争关系及抑制作用;5)8月15日—9月15日,IAA,GA3,ZR,ABA及(IAA+GA3+ZR)/ABA比值均呈下降趋势,表明促进生长类激素与导入休眠类激素均较低,泡桐顶芽和其他邻近组织相比其竞争优势在逐渐丧失,内源激素的动态平衡被打破。本研究结果初步探明顶芽死亡与内源激素的关联性,为进一步探讨泡桐死亡机理奠定基础。