番茄灰霉病生物防治菌株的筛选

从土壤中筛选出对番茄灰霉病菌(Botrytis cineren Pers．)有较强拮抗作用的生物防治菌株94株，其中拮抗细菌22株，分离率为17.6％；拮抗放线菌53株，分离率为11．7％；拮抗木霉菌19株，分离率为28.8％。研究发现，拮抗细菌可产生抗生素类物质，且在121℃高温下处理30min不失活，放线菌的抗生物质大多不耐热。拮抗木霉菌具较强的营养竞争及重寄生作用．温室接种试验表明对番茄叶部灰霉病的防治效果达67．18％。     

不同生物防治菌株对番茄灰霉病防治效果的影响

采用室内筛选的11个生物防治菌株进行盆栽和田间小区防治番茄灰霉病试验结果表明，细菌B27，真菌F45和F120，放线菌A15和A111，具有较好的预防效果，防治效果均在60％以上，其中放线菌A15菌株，防治效果达70％以上。菌株组合真菌F20＋F45和F20＋F120，F45＋F120和细菌B24＋B28具有增效作用。其中F45＋F120和B28＋B24组合．防治效果分别为69．2％和70.2％。     

稠油降解菌的筛选及其对胶质和沥青质生物降解

以稠油为唯一碳源,从辽河油田石油污染土壤、渣油中,经富集培养,分离筛选出细菌菌株11株、真菌23株和放线菌10株。将在含油培养基上长势良好的菌株进行室内摇瓶实验,发现真菌的降解效果好于细菌,F2006的降解效果最好,14d去除率达到39.8%。在胶质和沥青质污染土壤中,观察真菌F4、F2008、F9902、F2006、F2017、F6和F9904在14d、28d和42d对胶质和沥青质的去除率,测试结果表明,菌株F2006和F2008降解效果较好,在42d时去除率分别达到55.73%和57.62%。两次实验说明,菌株F2006为降解胶质和沥青质的优势菌株,在生物修复中具有较好的应用前景。     

保护地番茄根际微生物区系分析

采用常规微生物分离鉴定技术,分析了保护地番茄根际微生物区系。结果表明:在苗期、花期和果期,细菌和真菌数量明显上升,而放线菌数量下降;生育期不同真菌优势种类明显不同;颉颃灰霉病菌的微生物数量随生育期而下降;品种抗病性与颉颃微生物的数量表现出正相关。     

小麦白粉病潜在生防菌的筛选与控病特性研究

2001-2004年从山东，河南等11省采集土样78份，通过稀释平板法共分离菌株282株，其中真菌138株，细菌72株，放线菌61株。通过小麦白粉菌的孢子萌发抑制试验和小麦离体叶病害抑制试验的初步筛选，共得到12株防效较好的菌种。将所筛选的12个菌株进行温室盆栽苗病害控制试验。结果表明：细菌菌种PE4、C26、C27与真菌菌种P17-1对小麦白粉病抑制能力较强。防治效果分别达74．96％、70．1％、67．33％和64．71％。并对不同处理的小麦株高和千粒重进行方差分析。其中菌株PE4、C26、GE11处理的小麦千粒重分别为43．57，42．21，41．57g，与对照千粒重（29．22g）差异极显著。     

番茄灰霉病菌对嘧霉胺抗药性的试验

从辽宁省不同地区保护地采集番茄灰霉病菌。经单胞分离获得代表性菌株35株，彩菌丝生长速率法测定各菌株对嘧霉胺的敏感性。结果表明，番茄灰霉病菌已对嘧霉胺产生中等水平抗药性，抗性频率为22.9%。不同地区存在差异，嘧霉胺使用较多的锦州和瓦房店地区抗药性频率较高。在离体条件下，抗药性菌株具有良好的遗传稳定性，与敏感菌株相似适应能力。     

黄瓜苗病拮抗菌的筛选与活性测定

试验筛选出具有生物防治作用的3株细菌B2、B3、B9和1株真菌FT3（水霉菌）。它们对由立枯丝核菌（Rhizoctoniasolani)和瓜果腐霉菌（Pythium aphanidermatum)引起的苗病有较明显的防治效果，其中B9和FT3对由瓜果腐霉菌引起的苗病防治效果高达70％以上。B9和FT3在病菌接种量不高的条件下混合使用可表现出协同防病作用。化学农药福美双对生防细菌B9的防病功能有促进作用，但却抑制木霉菌的生物防治效果。     

不同抗、感枯萎病黄瓜品种不同生育时期根际微生物数量消长动态分析

通过对不同抗、感枯萎病黄瓜品种不同生育时期的根际微生物数量消长动态研究发现，黄瓜抗、感枯萎病品种的根际真菌、放线菌数量存在明显差异，且这些根际微生物数量与黄瓜的生育期有一定关系。在结瓜期抗病品种的真菌、放线菌数量明显多于感病品种，黄瓜的根际细菌数量与黄瓜抗性无相关性。根际真菌、放线菌数量在黄瓜初花期、结瓜期呈明显上升趋势，而细菌数量则呈波动变化，在初花期出现下降趋势。     

沼泽红假单胞菌培养条件研究

对光合细菌沼泽红假单胞菌(B9)的培养条件及培养基配方进行了研究。新筛选的培养基配方具有成分少、易配制、价格低的特点。试验结果表明，沼泽红假单胞菌(B9)是一株较耐低营养的微耗氧的菌株，在500—5000lx光照下能良好生长，最适的生长温度为30℃．培养周期为4d。     

外生菌根真菌促进油松人工幼林生长的应用研究

从不同林型下分离获得的外生菌根真菌纯培养菌株中,选择了其中劣味乳菇、赫丝膜菌、褐环乳牛肝菌、毛边滑锈伞4株优良菌处,对油松人工幼林（5年生）进行菌剂混合接种试验。结果表明：采用外生菌根真菌对油松幼林接菌,能够使土壤微生物种群数量发生变化;接菌后的土壤中的细菌、真菌、放线菌总数比不接菌的有明显的增加,其中真菌增加732.35%。对接菌油松进行菌根调查发现,接菌后的油松菌根侵染率为75％,不接菌的为20％;对连续两年接种菌剂的油松幼林调查发现,与不接菌剂的相比施用菌剂的油松地径、株高显增加。由此认为,外生菌根真菌作为一项生物接种技术对促进油松幼材的生长具有重要作用。     

基于光纤Bragg光栅的动态应变信号的解调研究

推导了基于非平衡M-Z干涉仪和直流相位跟踪零差法(PTDC)、相位载波零差法(PGC)2种相位检测方法的FBG动态应变信号解调系统的工作原理;搭建了振动试验系统,对2种解调系统进行了比较,试验证明:2种解调系统均能在10 kH z的频率范围内正常工作,但前者在测量范围、抑制噪声等方面有明显优势;构建了基于FBG的材料冲击试验系统,给出了试验参数,试验结果显示所检测信号的信噪比约为80 dB,最小能检测的动态应变相对量为10-4;研究证明:FBG在动态应变信号检测方面有良好的性能。     

Effect of cross-immunity on the transmission dynamics of two strains of dengue

A deterministic model for the transmission dynamics of two strains of dengue disease is presented. The model, consisting of mutually exclusive epidemiological compartments representing the human and vector dynamics, has a locally asymptotically stable, disease-free equilibrium whenever the maximum of the associated reproduction numbers of the two strains is less than unity. The model can have infinitely many co-existence equilibria if infection with one strain confers complete cross-immunity against the other strain and the associated reproduction number of each strain exceeds unity. On the other hand, if infection with one strain confers partial immunity against the other strain, disease elimination, competitive exclusion or co-existence of the two strains can occur. The effect of seasonality on dengue transmission dynamics is explored using numerical simulations, where it is shown that the oscillation pattern differs between the strains, depending on the degree of the cross-immunity between the strains.     

Analysis of dynamic strains in tibia during human locomotion based on flexible multibody approach integrated with magnetic resonance imaging technique

Bone is known to adapt to the prevalent strain environment while the variation in strains, e.g., due to mechanical loading, modulates bone remodeling, and modeling. Dynamic strains rather than static strains provide the primary stimulus of bone functional adaptation. The finite element method can be generally used for estimating bone strains, but it may be limited to the static analysis of bone strains since the dynamic analysis requires expensive computation. Direct in vivo strain measurement, in turn, is an invasive procedure, limited to certain superficial bone sites, and requires surgical implementation of strain gauges and thus involves risks (e.g., infection). Therefore, to overcome difficulties associated with the finite element method and the in vivo strain measurements, the flexible multibody simulation approach has been recently introduced as a feasible method to estimate dynamic bone strains during physical activity. The purpose of the present study is to further strengthen the idea of using the flexible multibody approach for the analysis of dynamic bone strains. Besides discussing the background theory, magnetic resonance imaging is integrated into the flexible multibody approach framework so that the actual bone geometry could be better accounted for and the accuracy of prediction improved.     

Influence of forced flectional vibrations on SF6 absorption on stainless steel FeNi

This experimental study concerns the adsorption and absorption on surfaces submitted to oscillating mechanical strains. The influence of the amplitude of the oscillating elastic deformations is shown during exposures of FeNi alloy surfaces to very low pressures of SF₆ (5 × 10⁻⁷ Torr). This study is carried out on a sample excited by a piezoelectric transducer observed in situ under ultra high vacuum (UHV) by Auger electron spectrometry (AES). An increase in the concentration of sulphur trapped on the surface is shown when the amplitude of oscillating elastic deformation increases. In any case, with or without mechanical strains, no traces of fluorine have been detected.     

Comments on the accuracy of nine-noded isoparametric finite elements

The reduction in accuracy in stress of nine-noded quadratic isoparametric elements related to the locations of the mid-side and centre nodes is shown to be due to erroneous relationships between strains and nodal displacements. The effect of nodal position on the calculated strains is discussed and criteria for the proper positioning of mid-side and centre nodes are provided.Errors associated with the use of curved sides are also examined and examples involving body force loading are used to illustrate the errors involved in the non-optimum location of nodes.The possibility of degenerating quadrilateral nine-noded isoparametric elements into triangular shaped elements is also studied. Recommendations to the user of finite element programs, in which nine-noded elements are incorporated are included.     

基于神经网络的堆石料本构模型参数反演

为准确估计堆石料力学本构模型参数,根据堆石料三轴压缩实验观测数据,提出一种基于神经网络的堆石料非线性本构模型参数反演方法。通过对三轴压缩实验轴向和径向应变的分段线性化处理,建立求解垂直荷载与应变之间关系的解析表达式。应用神经网络法对堆石料的力学模型参数进行反演,建立三轴压缩实验轴向和径向应变与模型参数之间的非线性映射关系,并据此进行堆石料模型参数估计。为验证反演方法的有效性,采用施工现场的堆石料进行三轴压缩实验,结果表明,与基于梯度优化搜索的参数估计方法相比,该方法具有更高的预测精度,最大相对误差降低了17.8%。     

灰霉病菌对多菌灵和乙霉威抗性研究

从１９９６年３～４月辽宁省主要蔬菜种植区采集的番茄、黄瓜灰霉病果上，分离得到２８２个灰葡萄孢霉（ＢｏｔｒｙｔｉｓｃｉｎｅｒｅａＰｅｒｓ．）菌株，测定了其对多菌灵和乙霉威的敏感性。结果表明，８７．２％的菌株为抗性菌株（ＢｅｎＲ），１２．８％的菌株为敏感菌株（ＢｅｎＳ）。中抗（ＢｅｎＩＲ）和低抗（ＢｅｎＷＲ）菌株为优势菌株。抗性菌株与敏感菌株在生长速率、产孢能力及致病力等方面无明显差异。作为苯并咪唑杀菌剂负交互抗性药剂而开发的Ｎ－苯基氨基甲酸酯杀菌剂乙霉威，对ＢｅｎＨＲ菌株具有优良的抑制作用，但对ＢｅｎＷＲ，ＢｅｎＩＲ和ＢｅｎＳ菌株的抑制作用很小。由多菌灵和乙霉威复配而成的多菌灵可有效控制ＢｅｎＨＲ和ＢｅｎＳ菌株对黄瓜子叶的侵染，但不能控制ＢｅｎＷＲ和ＢｅｎＩＲ菌株的侵染。     

Postprocessing of ADINA strains

A procedure has been developed for processing the strains available within ADINA to provide strain output in any desired orientation and to calculate and output strains on the surface of a 3-D solid shell element. To this end, proper additions and modifications have been made to ADINA to implement the procedure directly within the program to allow the processing and output of strains during the normal execution stage. This includes reading in additional input data (of minimum amount), transformation of strains from the global system to specified coordinate directions, the output of transformed strains, and the calculation and output of surface strains based on the interpolation functions available in ADINA. At the present time such capabilities are provided for a limited number of elements on a selective basis, in order to minimize the amount of computer storage required. Some typical structures have been analyzed to compute and output strains both at interior points and on exterior surfaces of elements, for a set of elements specified by the user during the input stage. Results demonstrate the feasibility of the procedure for the transformation and extrapolation of strains.     

防治大豆胞囊线虫病的土壤真菌的筛选

以辽宁省大豆田土壤中分离筛选获得的39株真菌菌株为研究对象,通过测定不同真菌菌株代谢产物浸出液在不同处理时间对大豆胞囊线虫二龄幼虫(J2)的抑制作用,评价不同菌株对大豆胞囊线虫的生防效果,从而进一步筛选出生防效果较好的菌株。结果表明,与对照相比不同菌株对大豆胞囊线虫的抑制作用具有显著差异。39株被测菌株中有7株表现出较强的抑制作用。其中真菌snf 2455-2的浸出液对大豆胞囊线虫有较强的致死作用。随着处理时间的延长,大多数菌株的抑制效果增强,同时具有抑制效果的菌株也增多。在处理72 h时,与对照相比有17株菌株抑制效果达到了显著水平。