抚仙湖水质的诱变性及其诱变因素分析

　为探讨抚仙湖水质的诱变性及诱变因素,用蚕豆根尖细胞微核检测法,检测抚仙湖水质的诱变性。用 高灵敏度的电感耦合氩等离子体发射光谱法( ICP2AES) 检测水体中5 种诱变性离子浓度。用GC/ MS(色相色谱/ 质谱) 联机检测水体中的有机化学污染物。结果表明:抚仙湖水质具有诱变性,且呈现水域性差异;水质的诱变性 非水体中诱变性离子所致;但与水体中有机化合物的种数有显著的相关性。

涡鞭毛虫类的染色质碱性蛋白研究及其进化地位的重新认识

通过对涡鞭毛虫这一特殊生物类群的染色质碱性蛋白研究的综述,并结合作者近来的工作和国际上有关的最新进展,对这类生物染色质碱性蛋白的特殊性和多样性进行了阐述。在此基础上对这类生物进化地位及系统发育进行了探讨。认为其染色质碱性蛋白不应是组蛋白的祖先蛋白,相反,它们是一些由于次生的原因而替代了组蛋白的碱性蛋白,并由于替代蛋白的不同而形成了它们的次生多样性;其染色质的特性即是由此而形成的与真细菌类核体的趋同相似性;其进化地位并非以前所认为的位于原核生物向真核生物的过渡环节,这类生物应是在真核细胞的基础上由于次生原因而形成的特殊类群;其系统发育也正是这一次生物进化过程的反映。

原白蚁的形态变异及其种类厘定商榷(等翅目:草白蚁科)

草白蚁科Hodotermitdae原白蚁亚科Hodotermopsinae目前仅知Zootermopsis,Archotermopsis和Hodotermopsis3个属。前1属分布于西半球的北美洲，后2属分布于东半球的东洋区。原白蚁属Hodotermopsis广泛分布于我国长江以南的丘陵地带，以及越南北部和日本南部的一些岛屿。这类白蚁取食木材，危害多种林木，一般生活在亚热带潮湿森林内，俗称湿木白蚁Dampwoodtermites。原白蚁属Hodotermopsis是N．Holmgren于1911年建立的，属于比较原始的类群。常筑巢于原木内，蚁巢结构比较简单，群体品级的分化亦处于较原始状态。幼蚁担负全巢劳作替代工以职能，故有拟工蚁之称。兵蚁的形态与成虫和幼蚁近似，其头部特别是个体小的头型近圆形，扁平；上颚粗壮，左右内缘多齿；触角节数多于20节；附节5节；尾须分节等。这些性状均保留了原始类型的特点。原白蚁形态变化颇大，有时似呈连续的梯度变异。如果采得少数个体，很容易将不同地方的种群或不同个体误定为不同种。原白蚁的模式种是H．sjbstedtiHolmgren。1912年，H0lmgren又以兵蚁右上颚齿的尖形与...

硒对小麦和水稻种子萌发的生态毒理效应的比较研究

通过水培试验,比较研究了硒在不同浓度下对小麦和水稻种子萌发及幼苗生长的生态毒理效应。结果表明,硒在适量范围内(<0.5 mg.L-1)对种子萌发过程中各生理指标有促进作用,高剂量(>5 mg.L-1)时,对种子活力、α-淀粉酶及幼苗和根生长具有胁迫效应。硒对小麦种子发芽各指标抑制率大于水稻,硒对种子根伸长的抑制率远远大于发芽抑制率。对硒浓度与种子发芽各项指标抑制率相关分析,呈显著正相关。应用小麦根伸长抑制率可作为化学物质生态风险评价的一项生物标志物。

长臀属鱼类多变量形态分析及物种有效性研究

采用形态度量学方法对分布于我国珠江水系、元江水系及海南岛诸水系的长臀属3种鱼类,共66尾个体的 43个测量性状进行了主成分分析。研究结果表明长臀属鱼类不能在形态上进行区别。作者认为长臀属鱼类 只存在一个有效种。

Effects of micronutrients on biological treatment efficiency of textile wastewater

Micronutrients play a very important role in biological processes for wastewater treatment. Many industrial wastewaters lack in nutrients (macronutrients and micronutrients) required for microbial growth, and this is one of the main problems at many activated sludge plants treating industrial wastewater. The microbial community structure is one of the important factors controlling the pollutant-degrading capacity of biological wastewater treatment system. In this study, the concentrations of micronutrients of the textile wastewater discharged from a textile plant were determined, and the effects of micronutrients on treatment efficiency and microorganism community structure of the biological treatment system were studied. The results showed that the optimal concentrations of magnesium, molybdenum, zinc, thiamine and niacin in the textile wastewater were 5.0, 2.0, 1.0, 1.0 and 1.0mg/L, respectively. The COD removal rates when magnesium, molybdenum, zinc, thiamine and niacin were added individually to the wastewater in their optimal concentrations were 1.8, 1.4, 1.3, 1.6 and 2.2 times of that of the control, respectively. The improving effects of combinations of zinc and thiamine, zinc and niacin, thiamine and niacin were better than single micronutrient. The diversity of quinones (DQ) changed significantly after the micronutrient was added into the wastewater treatment system. This indicated that there was probably a feasibility of optimizing the biological treatment performances and microorganism community structure of textile wastewater treatment system through micronutrient supplement.

Narrow line-width resonant cavity enhanced photodetectors operating at 1.55 mu m

A method for fabrication of long-wavelength narrow line-width InGaAs resonant cavity enhanced (RCE) photodetectors in a silicon substrate operating at the wavelength range of 1.3-1.6 mu m has been developed. A full width at half maximum (FWHM) of 0.7 nm and a peak responsivity of 0. 16 A/W at the resonance wavelength of 1.55 mu m have been accomplished by using a thick InP layer as part of the resonant cavity. The effects of roughness and tilt of the InP layer surface, and its free carrier absorption, as well as the thickness deviation of the mirror pair on the resonance wavelength shift and the peak quantum efficiency of the RCE photodetectors are analyzed in detail, and approaches for minimizing them toward superior performance are suggested. (C) 2007 Elsevier B.V. All rights reserved.

Broadband terahertz time-domain spectroscopy of drugs-of-abuse and the use of principal component analysis

EPSRC, the European Community IST FP6 Integrated, etc

低能离子束沉积制备GaAs:Gd的研究

对室温条件下用低能离子束沉积得到的GaAs∶Gd样品,借助X射线衍射(XRD)和高分辨X射线衍射(HR-XRD)进行了结构分析,结果表明没有出现新的衍射峰,并且摇摆曲线的形状与Gd的注入计量密切相关.运用X光电子能谱仪对比分析了Gd注入后,衬底中主要元素Ga2p和As3d的化学位移,以及不同计量的样品中注入的Gd4d芯能级束缚能的变化,并分析了铁磁性产生的可能原因.