等价电子组态原子光谱项推求方法

以同科电子f2组态光谱项推求为例,提出了用自旋因式化方法推求同科电子j-j耦合光谱项的一般方法。该法较为简单、适用,易于推广,可求出较复杂电子组态的原子光谱项。     

肇松松花江特大桥合拢段施工高程控制的研究

以肇松松花江特大桥的施工控制为背景,阐述了半刚构连续箱梁桥合拢段施工高程控制的影响因素和高程控制的方法。实践证明,肇松松花江特大桥成桥后的线形和合拢精度均达到施工规范的要求。     

2012年河南省开封市小麦品种利用及秋播布局建议

冬小麦在河南省开封市的重要性,小麦品种利用情况及品种种植适应分布。     

Long-term foliar persistence and efficacy of spinosad against beet armyworm under greenhouse conditions

BACKGROUND: The immediate lethality caused by spinosad has been widely studied on Spodoptera exigua (Hübner). However, long‐term effects can also provide valuable information on insecticide toxic action. Here, the persistence of spinosad on Capsicum annuum L. foliage and the lethal and sublethal effects of greenhouse‐aged foliar residues of this insecticide on third instars of S. exigua are reported. RESULTS: Foliage was collected at 0, 3, 5, 10, 20, 30, 40 and 50 days after application, and spinosad residues were measured. Residues decreased over time according to first‐order kinetics. The average rate constant and half‐life of disappearance were 4.44 × 10^?3 and 156 days and 5.80 × 10^?3 and 120 days for 60 and 120 mg L^?1 respectively. Larval mortality gradually decreased, corresponding to the residues, but was still appreciable (35 and 65% for 60 and 120 mg L^?1 respectively) when the larvae were fed with foliage collected 50 days after treatment. Subsequently, pupal development was reduced and varied between 20 and 60% and between 21 and 41% for 60 and 120 mg L^?1, respectively, in all ages of leaf residues that were bioassayed. At all time points, the consumption rate by the larvae was reduced between 62 and 84% for both concentrations that were bioassayed. CONCLUSION: It is concluded that, under the present greenhouse conditions, the degradation of spinosad was slower than that reported by other authors in the field, and, because of that, its residues could cause lethal and sublethal effects to S. exigua larvae. Copyright © 2011 Society of Chemical Industry     

水泥混凝土路面面板断裂原因分析及预防

作者对水泥砼路面施工时最常见的断板现象做了较系统的分析论述,提出了预防该现象发生的具体措施,充实了该项施工作业方法。     

高效储粮杀虫涂料的研究

运用微胶囊技术把氰戊菊酯与毒死蜱原药包裹在囊中，然后与涂料制成0．5％、1．0％、2，0％、5．0％杀虫涂料，经试验，2．0％～5．0％的微胶囊杀虫涂料对谷蠹Rhyzopertha dominica F．、玉米象Sitophilus zeamais Motschulsy、赤拟谷盗Tribolium castanoznensis L，杀灭率为100％，对书虱Atropus pulsatoria Linnaeus、螨Acarus类杀灭率在90％以上，1．0％的杀虫涂料对以上害虫杀灭率在90％以上，进口杀虫涂料对谷蠹、玉米象、赤拟谷盗杀灭率在85％以上，但对书虱、螨类无效。经成本核算，若采用3％新型杀虫涂料，成本仅为进口杀虫涂料的29．1～33．3％。     

有机磷农药的检测思考

我校化学实验室首次开放，76名志愿者报名参加了这次探索性实验。以敌百虫为例阐述了有机磷农药检测原理、操作步骤，记录了实验数据并对它们进行了处理，总结出有机磷农药使用的最高限量和使用标准。     

杉木人工林合理经营密度

根据闽北地区杉木丰产林110块样地的经营密度,应用半峰宽公式计算其合理经营密度。结果表明,最大密度模型的合理经营密度为0.64～0.88,最大密度线模型的合理经营密度为0.62～0.89;两种模型的经营密度经u检验表明没有显著差异;符号检验结果表明,两者的合理经营密度都适用于闽北地区杉木人工林的林分密度管理。     

油松半同胞子代及亲本木材管胞形态特征的比较

采取非破坏性取样法对油松不同家系木材管胞形态的比较研究与分析结果表明：油松子代测定林的木材管胞长度长,长宽比大,柔性系数高,是良好的纤维工业原料;家系间管胞长度变化大,家系内管胞长度差异显著,选择潜力大     

黑龙江省松嫩平原中部温凉半湿润区大豆品种比较试验

针对黑龙江省松嫩平原中部温凉半湿润区的农业生态特点和土质气候条件,进行了大豆品种比较试验,筛选出6个适宜该地区栽培的高产大豆品种,增产幅度达11.52%～34.25%,对促进黑龙江省大豆产业化发展具有重要意义.