硇洲岛周围水域虾拖网虾渔获组成

根据2005年渔业资源监测船生产调查资料和现场取样数据,运用数理统计方法分析了虾拖网虾渔获组成、生物学特征以及月份变化等。结果表明:硇洲岛周围水域虾拖网捕获的虾类主要是沿岸性底栖虾类,渔获中优质虾种少,幼虾比例高,墨吉明对虾、日本囊对虾、哈氏仿对虾是虾拖网渔业的主捕虾种,虾渔获组成存在明显的月份变化。为合理利用虾类资源和促进虾渔业可持续发展,应根据虾类特性开发适宜广东沿海虾拖网的选择性捕捞技术,减少幼虾兼捕量。     

计算刚架的矩阵迭代法

本文在迭代法基础上推导出矩阵迭代法的计算公式。用以编制程序,可节省容量,尤其适用于袖珍计算机。     

辐照技术在储粮害虫防治中的应用

辐照杀虫是利用电离辐射与害虫的相互作用所产生的物理、化学和生物效应,导致害虫不育或死亡的一种物理防虫技术.用于辐照杀虫处理的射线主要是γ射线(60Co或137Cs)、10 MeV以下电子束以及5 MeV以下的X射线,其中钴源辐照杀虫产业化发展迅速,电子束和X射线辐照发展相对滞后,随着近年来加速器技术的进步,电子束辐照杀虫显示出独特的优势,并受到越来越广泛的重视.辐照对不同储粮害虫、同一种储粮害虫的不同发育时期和性别有着不同的生物学效应,总体来看储粮害虫对辐照较为敏感:不同害虫的辐射敏感性顺序为:鞘翅目＞蜱螨目＞鳞翅目;同种害虫不同虫态的敏感性顺序为:卵、幼虫＞蛹＞成虫;雌性害虫的敏感性大于雄性害虫.粮食辐照杀虫工艺流程一般包括:辐照前处理、虫情调查、剂量决策、辐照处理、辐照后管理和重复辐照等几个部分.在辐照杀虫的工艺剂量(0.3～0.5 kGy)条件下,辐照对粮食的食用品质和功能特性没有影响,辐照后的粮食也不存在卫生安全性问题.因此,辐照杀虫技术作为一种安全有效的储粮害虫防治手段,是储粮化学药剂的一种重要补充和替代,在储粮害虫防治领域有着巨大的市场前景.     

A STRUCTURAL NON-LINEAR DYNAMIC STABILITY AND A MATRIX FUNCTION METNOD

This paper presents a mathematical and mechanic model for non-linear dynamicstability analysis of structures on the basis of Liapunov's stability criteria. Due to the complexityand difficulty in numerical calculation,a matrix function to this type of stability problems is selectedand the programing formulations are derived.Applying the method to beam or frame structures un-der the axial period loadings,the geometric non-linear dynamic stability results are obtained.Fromthe results,the basic characteristics of this type of probtems,especially the non-linear effect areshown.The model and matrix function method are valtiable both in theory and in practice for struc-tural non-linear dynamic stability.     

Calculation and Analysis of Finite Elements for Necked-inward Varied-section-beam

The calculation and analysis of static and modal are fulfilled with ANSYS for the entire super-architecture, its results are compared with that with TBSA and prepared for later pattern of particular analysis of finite elements. The new material pattern so-called Necked-inward Node is presented for necked-inward varied-section beams of super-architecture, ordinary software but ANSYS for the analysis of pattern is not fit.     

Experimental Study on a Prestressed Frame of Two Spans Under Unsymmetric Load

By the experimental study on a full-dimensioned prestressed frame of two spans, the relative factors are analyzed such as relative height of equivalent compression zone in critical section, secondary moment, ratio of beam rigidity to column and development of cracks in the top of columns etc., which influence the moment distribution of the post-tensioned prestressed concrete frame from the side of internal force redistribution. It is believed that that the factors of relative height of concrete equivalent compression zone and secondary moment influence the moment modulation in most degree, and ratio of column rigidity to beam also plays a part in the moment modulation to some extent. Second, the plastic joints of frame with excessive spans exit in the span which endure the whole load, at last the whole frame is destroyed because of the destruction of the loading frame, the influence to the non-loading span is little.     

电子流注入水稻幼穗组织培养效应的研究

以两用核不育系新光S幼穗为材料,以γ射线辐照作对照,研究了电子流注入对水稻离体培养的反应。结果表明,电子流注入对离体培养的效应与γ射线辐照具有相似性。对愈伤组织的诱导、分化主要表现为抑制效应,但对植株再生具有促进作用。10～15秒电子流注入可使幼穗的出愈率和分化率保持对照水平或略低,而再生能力大幅度提高。     

Electron donor and pH relationships for biologically enhanced dissolution of chlorinated solvent DNAPL in groundwater

Biologically enhanced dissolution offers a method to speed removal of chlorinated solvent dense non-aqueous-phase liquid (DNAPL) sources such as tetrachloroethene (PCE) and trichoroethene (TCE) from aquifers. Bioremediation is accomplished by adding an electron donor to the source zone where fermentation to intermediates leading to acetic acid and hydrogen results. The hydrogen and possibly acetic acid are used by dehalogenating bacteria to convert PCE and TCE to ethene and hydrochloric acid. Reductive dehalogenation is thus an acid forming process, and sufficient alkalinity must be present to maintain a near neutral pH. The bicarbonate alkalinity required to maintain pH above 6.5 is a function of the electron donor: 800 mg/L of bicarbonate alkalinity is sufficient to achieve about 1.2 mM TCE dechlorination with glucose, 1.7 mM with lactate, and a much higher 3.3 mM with formate. Laboratory studies indicate that in mixed culture, formate can be used as an electron donor for complete conversion to ethene, contrary to pure cultures studies indicating it cannot. Various strategies can be used to add electron donor to an aquifer for DNAPL dehalogenation while minimizing pH problems and excessive electron donor usage, including use of injection-extraction wells, dual recirculation wells, and nested injection-extraction wells.     

观赏植物诱变育种的研究现状和展望

本文综述了观赏植物辐射诱变育种的研究现状,并对花卉辐照诱变的手段、方法、处理材料和适宜辐照剂量、辐照机理与方法及应用作了总结,同时对观赏植物辐射诱变育种存在的问题及发展方向进行了探讨。