Genetic diversity of Tricholoma matsutake in Yunnan Province

To investigate the genetic diversity of Tricholoma matsutake, we studied ITS and IGS1 sequences and PCR polymorphism of a retrotransposon in 56 fruit bodies collected from 13 counties of 9 regions in Yunnan Province. We found one and three haplotypes base

大型瑵HB对五氯苯酚的富集与释放动力学研究

大型瑵ＨＢ对五氯苯酚的富集与释放动力学研究谭渝云，孙美娟（中国科学院水生生物研究所，武汉，４３００７２）关键词大型；动力学；富集：释放；五氯苯酚．五氯苯酚（ＰＣＰ）是一种应用十分广泛的杀虫剂和防腐剂，Ｄｅｔｒｉｃｋ报道了世界上ＰＣＰ每年施用量约为９×...

一种耐高温大型溞HB的培养和生物学的初步研究

本文介绍了夏季在武汉鱼池所采的耐高温大型溞(Daphnia magna HB),对其生长繁殖及其实验室条件下溞的种群密度、食物、温度和光照强度对生长、发育的影响,并对其培养和保种方法进行了研究。连续3年实验室的培养表明,在以新鲜藻类为食物的情况下,此种溢在15—31℃时能正常生长、繁殖。在31℃时,其最大体长为3.65mm,最高怀卵量为26个。根据国际标准法组织所介绍的(ISO 6341)对标准毒物——重铬酸钾的敏感性试验,24hEC_(50)为0.92mg/L(20%)。

HB型厌氧生物工艺净化染色废水中间试验

<正> 染色废水作为一种主要污染源对环境构成的严重危害人所共知。随着“四化”建设的发展和人民生活水平的提高,轻纺工业在全国大、中、小城市乃至乡村小镇蓬勃发展,给污染防治工作带来极为艰巨的任务。至今,国内外染色废水的净化采用了多种物理化学和生物氧化的方法,虽有一定效果,也存在不同程度的问题,如电耗大、脱色率

HB型厌气工艺处理染色废水的研究 Ⅰ、HB-1型厌气反应器运转试验

<正> 染色废水长期以来是世界公认的严重污染源之一。基于染料类型的多样性和化学结构的复杂性,给废水处理带来了一定的难度。在桥本 茂等(1981)对多种染料及其助剂的COD、BOD、TOC、磷素和氮素值的研究中,已证明了上述事实。目前,国

Toxicity of cypermethrin to Daphnia magna HB

The acute toxic effect of the pesticide cypermethrin to Daphnia magna HB was examined. D. magna HB was exposed to cypermethrin at concentrations of 0, 1, 3, 5, 7, and 9 mg/L for 24 In. Data showed that the 24 h-LC50 of cypermthrin on D. magna HB was 4.81 mg/L. In contrast, the 24 h-LC50 of K2Cr2O7 (the national standard toxicant) to Daphnia magna was 0.38 mg/L in the current study. Results indicated that the Daphnia magna was very sensitive to pesticides. In addition, the effects of the culture condition(such as hardness, temperature and DO etc.) on Daphnia magna HB was also studied.

利用深部非弹反应对Z≈56,N≈80区核激发态的探索性研究

通过 4 1 0MeV82 Se轰击天然Ba靶引起的深部非弹反应布居产生了类弹和类靶余核的激发态 ,利用在束γ谱学方法测量了它们的退激γ .通过γ -γ符合测量估计了类弹、类靶余核激发态的产生截面 ,在多个类靶余核中观测到了新γ跃迁 ,并建立了136 Ba的新能级纲图 ,说明利用深部非弹反应研究Z≈ 56,N≈ 80区高自旋态是有效、可行的

Study of mass distributions of quasifission products based on dinuclear system

In the concept of dinuclear system, the quasifission rate from Kramers formula has been incorporated in the master equation in order to study the competition between fusion and qusifission. Mass yields of quasifission products of the three reactions Ca-48 + Pu-244, Ca-48 + U-238 and Fe-58 + Th-232 have been calculated, and the experimental data are reproduced very well, which is a critical test for the existing fusion model. Also we have shown the time evolution of the mass distributions of quasifission products, which provides valuable information of the process of competition between fusion and quasifission.

The influence of nuclear orientation in fusion dynamics

Fusion barriers have been calculated for different orientations of the axial symmetry axis of deformed projectile-and target-nucleus. Using the concept of dinuclear system, considering the strong competition between fusion and quasifission processes, by solving the master equation numerically to calculate the fusion probability of superheavy nuclei, we have estimated the dependence of the fusion probabilities for Ge-76 + Pb-208 and Ca-48 + Pu-244 on the orientation angles of the symmetry axis of projectile-and target-nucleus, which shows that belly-belly is the most favorable orientation for synthesizing superheavy nuclei.

Radiosensitivity to high energy iron ions is influenced by heterozygosity for Atm, Rad9 and Brca1

Loss of function of DNA repair genes has been implicated in the development of many types of cancer. In the last several years, heterozygosity leading to haploinsufficiency for proteins involved in DNA repair was shown to play a role in genomic instability and carcinogenesis after DNA damage is induced, for example by ionizing radiation. Since the effect of heterozygosity for one gene is relatively small, we hypothesize that predisposition to cancer could be a result of the additive effect of heterozygosity for two or more genes critical to pathways that control DNA damage signaling, repair or apoptosis. We investigated the role of heterozygosity for Aim, Rad9 and Brad on cell oncogenic transformation and cell survival induced by 1 GeV/n Fe-56 ions. Our results show that cells heterozygous for both Aim and Rad9 or A tin and Brca1 have high survival rates and are more sensitive to transformation by high energy iron ions when compared with wild-type controls or cells haploinsufficient for only one of these proteins. Since mutations or polymorphisms for similar genes exist in a small percentage of the human population, we have identified a radiosensitive sub-population. This finding has several implications. First, the existence of a radiosensitive sub-population may distort the shape of the dose response relationship. Second, it would not be ethical to put exceptionally radiosensitive individuals into a setting where they may potentially be exposed to substantial doses of radiation. (C) 2010 COSPAR. Published by Elsevier Ltd. All rights reserved.

The Compact Pulsed Hadron Source: A Design Perspective

During the past. decades, large-scale national neutron sources have been developed in Asia, Europe, and North America. Complementing such efforts, compact hadron beam complexes and neutron sources intended to serve primarily universities and industrial institutes have been proposed, and some have recently been established. Responding to the demand in China for pulsed neutron/proton-beam platforms that are dedicated to fundamental and applied research for users in multiple disciplines from materials characterization to hadron therapy and radiography to accelerator-driven sub-critical reactor systems (ADS) for nuclear waste transmutation, we have initiated the construction of a compact, yet expandable, accelerator complex-the Compact Pulsed Hadron Source (CPHS). It consists of an accelerator front-end (a high-intensity ion source, a 3-MeV radio-frequency quadrupole linac (RFQ), and a 13-MeV drift-tube linac (DTL)), a neutron target station (a beryllium target with solid methane and room-temperature water moderators/reflector), and experimental stations for neutron imaging/radiography, small-angle scattering, and proton irradiation. In the future, the CPHS may also serve as an injector to a ring for proton therapy and radiography or as the front end to an ADS test facility. In this paper, we describe the design of the CPHS technical systems and its intended operation.

近56年来科尔沁沙地气候变化特征

根据1951—2006年的气温和降水资料,研究了干旱少雨、生态环境脆弱、土地荒漠化严重的科尔沁沙地近56年的气候变化特征。结果表明:1951—2006年,科尔沁沙地的气温以0.28℃.10a-1的速度上升,远大于全球近50年来0.13℃.10a-1的平均增温速率;各季节气温都呈上升趋势,冬、春季增温速率极显著(P<0.001),增温速率分别为0.46和0.39℃.10a-1;年最高气温(0.17℃.10a-1)与年最低气温(0.42℃.10a-1)均呈极显著地增加趋势(P<0.01);降水量年际间波动较大,无明显的变化趋势,各季节降水量也没有明显的变化规律;年降水日数呈显著减少趋势(1.3d.10a-1),各季的降水日数虽都有逐年减少趋势,但没有达到显著水平;年降水强度和各季降水强度都没有明显的变化规律;年总小雨日数呈显著的减少趋势(P<0.05),减少速率为1.0d.10a-1。

用固定化Oil-56黄杆菌修复地表水菌体形态变化

利用聚乙烯醇-海藻酸钠(PVA-Na.A lg)联合包埋固定化一株黄杆菌O il-56,进行污染地表水修复实验研究,结果表明固定化细菌的修复效果明显好于游离细菌。同时利用扫描电子显微镜观察了固定化颗粒内部细菌形态的变化,解释了由于Na.A lg溶解导致水体CODC r升高的原因,并分析了固定化颗粒传质扩散性能的缺陷,指出PVA-Na.A lg固定化工艺尚需改进。