水平连续铸钢凝固过程数值模拟

本文在分析水平连铸传热特征的基础上，给出了一维情况下，计算结晶器出口处铸坯凝固层厚度的解析式，建立了计及轴向传热的连续坯凝固模拟模型。进行了连续坯二维传热的凝固数值模拟，其模拟结果与实验结果吻合较好，具有普遍应用价值。     

外源复合酶对移地保护圈养马来熊日粮营养消化率的影响

利用外源复合酶对移地保护圈养的 9只马来熊日粮营养物质及能量消化率进行了测定 ,经单因子方差分析结果表明 ,在圈养马来熊日粮中添加一定量的外源复合酶 ,能提高马来熊对日粮营养物质的消化率 ,其中 ,添加 0 3%饲料量的酶能显著提高日粮粗蛋白的消化率(P <0 0 5) ;添加 0 5%的酶 ,能显著提高日粮粗纤维、粗蛋白质消化率 (P <0 0 5)。此研究结果可应用于马来熊的饲养中 ,提高其饲料报酬     

Tuberculosis in wild seals and characterisation of the seal bacillus

SUMMARY Tuberculosis was diagnosed in 3 otariid seals found dead on beaches at 3 locations on the south coast of Western Australian between May 1990 and March 1991. This confirms that tuberculosis is present in the 2 native seals (Neophoca cinerea and Arctocephalus forsteri) in Western Australian waters. Mycobacterium sp isolated from the lungs of 2 of the seals were studied to determine the similarity of the strains to each other, to the strains isolated during 1986 from Australian sea lions and New Zealand fur seals kept in captivity at a marine park near Perth, Western Australia, and to a strain isolated in 1988 from a seal trainer who worked with the infected captive seals for 3 years. After restriction endonuclease analysis (REA) with the endonucleases Bst Ell, Bcl I and Pvu II, one of the wild seal strains appeared to have identical DNA fragment patterns to the strains from the captive seals and the seal trainer. The other wild seal isolate had identical REA profiles using Bst EII and Bcl I, but a minor difference was detected using Pvu II. Differences in these isolates were more clearly seen in restriction fragment length polymorphisms after hybridisation with two DNA probes. The secretory protein MPB70, present in M bovis, was not detected in wild seal isolates using sodium dodecyl sulphate polyacrylamide gel electrophoresis and Western blotting techniques. Analysis of protein and DNA fragment profiles indicated that seal tuberculosis isolates form a unique cluster within the M tuberculosis complex.     

普通番茄与秘鲁番茄杂种后代的形态,亲和性及抗性表现

继获得普通番茄‘北京早红’与秘鲁番茄杂交种后,本试验着重于对杂种后代的形态、亲和性及抗性表现的观察,杂种的多数性状为双亲中的显性性状或双亲的中间型,但也表现了一些奇异性状,如果实的颜色和花序的形状与排列通过株间的“杂交”克服了杂种的高度自交不亲和性,从而顺利得到杂种的自交后代;杂种各世代均高抗TMV 0株系和1株系,并有部分选系抗TMV 1·2株系,由此判断秘鲁番茄亲本可能具有TM~a_2基因;用南京地区CMV厥叶株系和强株系分别接种,各世代表现部分抗病或耐病。     

河北省小五台山国家级自然保护区蜘蛛名录(Ⅱ)

通过2004和2005年对小五台山国家级自然保护区内蜘蛛多样性的再次调查、采集、鉴定和整理,补充未记录的蜘蛛77种,至此,小五台山的蜘蛛共有31科114属234种.     

退化草地土壤生化活性研究

通过对三种不同退化程度的退化草地土壤生化活性进行测定和相关性分析，结果表明草地退化后其土壤生化活性受到不同程度的影响，表现为土壤生化活性随着退化程度增高而减小，但差异并非都达到统计学上的显著性，而土壤生化活性间的相关性则显著地与草地退化程度有关，说明退化草地土壤微生物间的协调作用受到显著影响，从而影响土壤氮素和碳素代谢途径。     

Comparison of an enzyme-linked immunospecific assay (ELISA) with the cold complement fixation test for the serodiagnosis of Brucella ovis infection

An enzyme-linked immunospecific assay (ELISA) for the serodiagnosis of Brucella ovis infection in sheep is described and compared with the cold complement fixation (CF) test. ELISA was performed in microtiter plates, using horse-radish peroxidase conjugated to anti-normal sheep serum globulins, and hydrogen peroxide plus o-phenylenediamine as substrate. A heated, cell-free B. ovis extract was used as antigen in both tests. ELISA was easier to perform, distinguished better between positive and negative sera, and did not need heat-inactivated sera.     

New predators for biocontrol under glass

Several species ofOrius are under investigation in the UK, Europe and North America for the biological control of thrips, especially western flower thrips(Frankliniella occidentalis). The available species are briefly compared and findings on effectiveness and oviposition ofO. laevigatus are reported.     

潜叶蝇在大庆市日光温室蔬菜上的发生与为害

对潜叶蝇在北方节能日光温室蔬菜上的发生和为害进行调查研究。结果表明,3～11月潜叶蝇在日光温室蔬菜上均有发生,其中5月中旬～6月中旬、9月下旬～10月中旬是为害高峰期;一日中9:00～11:00、13:00～15:00是潜叶蝇成虫为害高峰期;3月下旬、6月上中旬潜叶蝇/明显升高。     

离体条件下水稻种衣剂对串珠镰刀菌生长及形态毒理影响

 检测了黑龙江水稻主产区4个当地主栽品种的种子内部镰刀菌寄藏情况,测定了20%克福甲和20%克多甲种衣剂对种子带菌消毒处理效果及对水稻串珠镰刀菌(Fusarium moniliforme)的抑菌作用和联合毒力,并借助扫描电镜观察了上述2种混配种衣剂对串珠镰刀菌的形态毒理影响。结果表明,种子内部镰刀菌的分离频率高达56.7%~96.0%,其中串珠镰刀菌的分离频率为32.6%~48.2%,2种种衣剂对带菌种子具有显著的消毒处理效果。20%克福甲和20%克多甲种衣剂对镰刀菌F.moniliforme的毒力指数分别为457.11和802.04,增效倍数分别为6.53和0.13。20%克多甲种衣剂(多菌灵:甲基立枯磷为5:5,W/W)对串珠镰刀菌的抑菌作用优于20%克福甲种衣剂(福美双:甲基立枯磷为8:6,W/W),增效作用低于20%克福甲种衣剂。电镜观察表明,种衣剂低浓度至高浓度处理下均可引起串珠镰刀菌菌丝不同程度的异常生长,表现为主菌丝局部膨大或形成菌丝束,菌丝顶端异常膨大、缢缩或形成穗状和花絮状分枝。