第57届国际宇航大会会议介绍

1概况 第57届国际宇航大会于2006年10月2—6日在西班牙瓦兰西亚召开，10月1日还召开了国际宇航科学院院士会和国际宇航学会各委员会会议．会议参加人数超过2000人，开幕式大礼堂座无虚席．这次会议的主题是“开创更贴近人民的空间事业（bringing space closer to people）”．大会在瓦兰西亚的大展览馆召开，群众与代表交混．除大会会场外，所有分会会场都是用木板临时安装的，会场条件简单．

激光熔覆大厚度Fe_(57)Co_8Ni_8Zr_(10)Si_4B_(13)非晶表层及其微结构研究

利用激光熔覆制备出1.2mm厚的Fe_(57)Co_8Ni_8Zr_(10)Si_4B_(13)大厚度非晶表层。用XRD,ES,TEM,DSC及硬度对获得的非晶表层进行了多种分析，研究了非晶合金表层的微结构与非晶形成能力。初步探讨了大厚度非晶表层的形式机制。

联合固氮菌Enteroabcter gergoviae 57-7氮代谢相关基因的克隆和泌氨工程菌的构建

从构建具有稳定泌氨能力的联合固氮工程菌的目的出发，首先构建Enterobacter gergoviae57-7 (E57-7)基因文库并与所筛选的泌氨突变株进行遗传互补实验，得到可互补 泌氨特性的克隆，经Southern杂交后推测其中包含与glnA、amtB基因无关的另一类与泌 氨相关的基因。同时根据铵载体基因amtB的已知序列设计两对简并性引物，经PCR从 E57-7 DNA中扩增得到约340bp的片段，序列分析和Blast序列同源性比较后确定为amtB 基因片段，申报并获得序列号AJ132232，最终从基因库中筛选到两个包含E57-7 amtB 基因的克隆。 用K. pneumoniae的glnA基因片段为探针，通过Southern杂交从E57-7基因库中筛选到包含有glnAntrBC基因的克隆，经亚克隆后对包含有这个操纵元的4316bp片段进行了全序列分析，申报GenBank获得序列号AF072440。在体外实验中构建了Km-cassette 插入glnA的重组质粒pA，将此质粒转入E57-7野生型菌株后经筛选同源重组子获得glnA 突变的具有稳定泌氨能力的菌株15、I9。并进行了盆栽玉米接种实验，确定在灭菌上壤实验体系下I5对玉米幼苗有显著促生效应。 利用绿色荧光蛋白(GFP-S65T，V68L，S72A)基因建立分子生物学研究手段，构建了新 型克隆载体pGreenLD，建立了绿白斑筛选重组质粒的的技术。构建组成型表达gfp的质粒载体研究了E57-7在玉米根际的定殖模式;构建nifH-gfp表达载体，确定在与植物联合生活时其固氮酶结构基因nifHDK的表达与碳源物质供应密切相关。利用不同抗性基因和gfp基因片段构建出在E57-7中组成型表达抗性和GFP的质粒载体，建立了监测接种菌在土壤中释放的双标记系统。 最后克隆了E57-7 glg cluster并测定部分glgCA和glgP基因序列，申报后获得序列号AJ132233和AJ132234，这是首例从联合固氮菌中克隆得到glg cluster的报道。

How polluted is the Yangtze River? Water quality downstream from the Three Gorges Dam

The concentrations of major anions and cations, nitrogen and phosphorus, dissolved and particulate trace elements, and organic pollutants were determined for the middle and lower reaches of the Yangtze River (Changjiang) from below the Three Gorges Dam (TGD) to the mouth at Shanghai in November 2006. The concentration of dissolved inorganic phosphate (DIP) was constant at a low level of 6-8 mu gP/L, but the concentration of nitrate (NO3-) approximately doubled downstream and was closely correlated with K+. This translated to a daily load of well over 1000 It of dissolved inorganic nitrogen (DIN) at Datong. The average concentrations of dissolved Pb (0.078 +/- 0.023 mu g/L), Cd (0.024 +/- 0.009 mu g/L), Cr(0.57 +/- 0.09 mu g/L), Cu (1.9 +/- 0.7 mu g/L), and Ni (0.50 +/- 0.49 mu g/L) were comparable with those in other major world rivers, while As (3.3 +/- 1.3 mu g/L) and Zn (1.5 +/- 0.6 mu g/L) were higher by factors of 5.5 and 2.5, respectively. The trace element contents of suspended particles of As (31 +/- 28 mu g/g), Pb (83 +/- 34 mu g/g), and Ni (52 +/- 16 mu g/g) were close to maximum concentrations recommended for rivers by the European Community (EC). The average concentrations of Cd (2.6 +/- 1.6 mu g/g), Cr (185 +/- 102 mu g/g), Cu (115 +/- 106 mu g/g), and Zn (500 +/- 300 mu g/g) exceeded the EC standards by a factor of two, and Hg (4.4 +/- 4.7 mu g/g) by a factor of 4 to 5. Locally occurring peak concentrations exceed these values up to fourfold, among them the notorious elements As, Hg, and Tl. All dissolved and particulate trace element concentrations were higher than estimates made twenty years ago [Zhang, J., Geochemistry of trace metals from Chinese river/estuary systems: an overview. Estuar Coast Shelf Sci 1995; 41: 631-658.]. The enormous loads of anthropogenic pollutants disposed to the river were diluted by the large water discharge of the Yangtze even during the lowest flow resulting in the relatively low concentration levels of trace elements and organic pollutants observed. We estimated loads of e.g. As, Pb and Ni to the East China Sea to be about 4600 kg As d(-1), 3000 kg Pb d(-1), and 2000 kg Ni d(-1). About 6000 t d(-1) of dissolved organic carbon (DOC) was delivered into the sea at the time of our cruise. We tested for 236 organic pollutants, and only the most infamous were found to be barely above detection limits. We estimated that the load of chlorinated compounds, aromatic hydrocarbons, phenols, and PAHs were between 500 and 3500 kg d(-1). We also detected eight herbicides entering the estuary with loads of 5-350 kg d(-1). The pollutant load, even when at low concentrations, are considerable and pose an increasing threat to the health of the East China Sea ecosystem. (c) 2008 Elsevier B.V. All rights reserved.

Fe-57 Mossbauer spectroscopic and magnetic studies of R3Fe29-xVx (R = Y, Ce, Nd, Sm, Gd, Tb, and Dy)

Mossbauer spectra for Fe atoms in the series of R3Fe29-xVx (R = Y, Ce, Nd, Sm, Gd, Tb, and Dy) compounds were collected at 4.2 K. The ratio of 14.5 T/mu(B) between the average hyperfine field B-hf and the average Fe magnetic moment mu(Fe)(MS), obtained from our data, in Y3Fe29-xVx is in agreement with that deduced from the RxTy alloys by Gubbens et al. The average Fe magnetic moments mu(Fe)(MS) in these compounds at 4.2 K, deduced from our Mossbauer spectroscopic studies, are in accord with the results of magnetization measurement. The average hyperfine field of the Fe sites for R3Fe29-xVx at 4.2 K increases with increasing values of the rare earth effective spin (g(J) - 1) J, which indicates that there exists a transferred spin polarization induced by the neighboring rare earth atom.

Mossbauer spectroscopy study of Fe-57 in R3Fe29-xTx (R=Y, Ce, Nd, Sm, Gd, Tb and Dy; T=V and Cr)

Fe-57 Mossbauer spectra for the Fe atoms in the R3Fe29-xTx (R=Y, Ce, Nd, Sm, Gd, Tb, Dy; T=V, Cr) compounds were collected at 4.2 K. The analysis of Mossbauer spectra was based on the results of magnetization and neutron powder diffraction measurements. The average Fe magnetic moments at 4.2 K, deduced from our data, are in accord with magnetization measurements. The average hyperfine field of Tb3Fe29-xCrx (x=1.0, 1.5, 2.0, and 3.0) decreases with increasing Cr concentration, which is also in accordance with the variation of the average Fe magnetic moment in the Tb3Fe29-xCrx compounds.

Fe-57 Mossbauer spectroscopic and magnetic studies of R3Fe29-xVx (R = Y, Ce, Nd, Sm, Gd, Tb, and Dy)

Mossbauer spectra for Fe atoms in the series of R3Fe29-xVx (R = Y, Ce, Nd, Sm, Gd, Tb, and Dy) compounds were collected at 4.2 K. The ratio of 14.5 T/mu(B) between the average hyperfine field B-hf and the average Fe magnetic moment mu(Fe)(MS), obtained from our data, in Y3Fe29-xVx is in agreement with that deduced from the RxTy alloys by Gubbens et al. The average Fe magnetic moments mu(Fe)(MS) in these compounds at 4.2 K, deduced from our Mossbauer spectroscopic studies, are in accord with the results of magnetization measurement. The average hyperfine field of the Fe sites for R3Fe29-xVx at 4.2 K increases with increasing values of the rare earth effective spin (g(J) - 1) J, which indicates that there exists a transferred spin polarization induced by the neighboring rare earth atom.

Mossbauer spectroscopy study of Fe-57 in R3Fe29-xTx (R=Y, Ce, Nd, Sm, Gd, Tb and Dy; T=V and Cr)

Fe-57 Mossbauer spectra for the Fe atoms in the R3Fe29-xTx (R=Y, Ce, Nd, Sm, Gd, Tb, Dy; T=V, Cr) compounds were collected at 4.2 K. The analysis of Mossbauer spectra was based on the results of magnetization and neutron powder diffraction measurements. The average Fe magnetic moments at 4.2 K, deduced from our data, are in accord with magnetization measurements. The average hyperfine field of Tb3Fe29-xCrx (x=1.0, 1.5, 2.0, and 3.0) decreases with increasing Cr concentration, which is also in accordance with the variation of the average Fe magnetic moment in the Tb3Fe29-xCrx compounds.

~(57)Fe,~(119)Sn掺杂Bi_2Sr_2Ca_(n-1)Cu_nO_(2n+4)的化学键性质和Mssbauer谱位移研究

利用电介质的平均能带模型计算了Bi2 Sr2 Can- 1CunO2n +4 (n =1,2 ,3)的化学键参数 .应用由共价性和极化率定义的化学环境因子计算了57Fe和119Sn在Bi2 Sr2 Can - 1CunO2n +4 中的M ssbauer同质异能位移 ,确定了57Fe和119Sn在Bi2 Sr2 Can- 1CunO2n +4 中的价态和占位情况 .

Mossbauer spectra of Fe-57 in a thick film of YBa2(Cu0.97Fe0.03)(3)O7-x irradiated by a large dose of gamma-rays

Mossbauer spectra of Fe-57 in a thick film YBa2(Cu0.97Fe0.03)(3)O7-x irradiated by a large dose of gamma-rays from Co-60 have been measured. The variation of the relative intensities of some subspectra of Fe-57 in the. Mossbauer spectra of the thick film YBa2(Cu0.97Fe0.03)(3)O7-x after irradiation can be observed. This variation indicates that the change of the coordination environment around some Fe atoms in the lattice occurs due to irradiation. The relative intensity of subspectrum D1(Fe) at the Cu(1) site decreases and that of subspectrum D4(Fe) at the Cu(1) site increases. This may be because of the possible oxygen atom hopping between the coordination environments of D1(Fe) and D4(Fe) in the lattice caused by irradiation. The effect of irradiation on the coordination environment around the Fe atom at the Cu(2) site is not appreciable. (C) 1997 Elsevier Science B.V.

菲律宾蛤仔（Ruditapes philippinarum)能量代谢的研究

能量代谢指动物在进行生理活动(如摄食、消化以及动物的活动等)时所消耗能量的总和，一般以动物的呼吸率利排泄率来估计动物的能量代谢。其主要研究内容是闸明生物能量代谢的基木规律以及与环境闪子的关系。菲律宾蛤仔(Ruditapesphil ippmarum)是我国一种重要的养殖贝类，关于其能量代谢的研究却较少，这种状况妨碍了菲律宾蛤仔养殖生态理论的完善和养殖技术的提高。本研究主要对菲律宾蛤仔呼吸率和排泄率的基本规律(能量代谢与体重的关系、能量代谢的昼夜变化)及其与环境因子(饵料浓度、水温、栖息底质环境)的关系进行探讨。研究结果如下：1．不同体重菲律宾蛤仔代谢率小同。实验川菲律宾蛤仔分三种大小：l(干肉重为0．07-0．14g)、ll(干肉重0．27-0．34g)、III(干肉重0．45～0．63g)。温度包括：26℃(八月)、20℃(十月)、1 5℃(十二月)、9℃(一月)。实验共设四个饵料浓度：2．28±0．25，6．454±0．44，10．284±0．82，15．414±1．56mgTPM／L(TPM，总颗粒物)，饵料中POM(颗粒有机物)含量都为4．68±1．64 mg/L。常温下菲律宾蛤仔代谢率随着体重的增大而增大。15℃、20~C、26℃时蛤仔呼吸率与干肉重呈明显的幂函数关系R=aW~b，a值变动范围为0．1076-0．3309；b值变动范围为0．239l～0．8381；蛤仔排泄率与干肉重也呈明显的幂函数关系N=aW~b，a值变动范围为14．213～68．362：b值变动范围为0．3673-1．1 532。9℃(饵料浓度为2．28±0．25mgTPM／L)、20℃(饵料浓度为10．284-0．82mgTPM／L)、26℃(饵料浓度为6．454±0．44mgTPM／L)时不同体重蛤仔氧氮比差异显著，其它情况下不同体重蛤仔氧氮比差异不显著。2．常温下菲律宾蛤仔代谢率受饵料浓度的影响，不同大小蛤仔受饵料浓度的影响程度不同。I组蛤仔呼吸率受饵料浓度的显著影响，II组III组蛤仔呼吸率只在9℃(一月)和26~C(八月)时受饵料浓度的显著影响。26℃时影响最显著，26℃时I组蛤仔在饵料浓度为2．28±0．25，6．45±0．44，l0．28±0．82，15．4l±1．56mgTPM／L时呼吸率分别是O．086，0．146，0．073，0．093(mlO_2／h)；ll组蛤仔在上述浓度饵料中呼吸率分别是0．138，0．214，0．J 26，0．12l(mlO_2／h);III组蛤仔在上述浓度饵料中呼吸率分别是0．129，0．266，0．186，0．192(mlO_2／h)。菲律宾蛤仔呼吸率在饵料浓度为6．45±0．44 mgTPM／L时最高，蛤仔呼吸率在其它饵料浓度时都会降低。菲律宾蛤仔排泄率在饵料浓度为10．28±0．82 mgTPM／L和15．4l士1．56mgTPM／L时显著高于其它浓度组，9℃时这种趋势更明显，9℃时饵料浓度为2．28±0．25，6．454±044，lO．284±0．82，15．41±1．56mgTPM／L中I组蛤仔排泄率分别是4．297，2．874，8．003，6．658(μgNH_3-N／h)；II组蛤仔在上述浓度饵料中排泄率分别是4．011，3．609，10．427，12．732(μgNH_3-N／h)；III组蛤仔在上述浓度饵料中排泄率分别是2．28 l，6．452，10．283，15．417(μgNH_3-N／h)。3．菲律宾蛤仔代谢率受自然温度的显著影Ⅱ向。I组蛤仔在9℃、15℃、20℃、26℃时呼吸率平均为0．057，0．085，0．039，O．099；II组蛤仔在上述四个温度中呼吸率平均为0．08，O．128，0．089，0．149(mlO_2／h)，I组和II组蛤仔在9℃和20~C时呼吸率较低，在26℃时呼吸率最高。III组蛤仔在上述四个温度中呼吸率平均为0．09，O．1 59，O．143，O．193(mlO_2／h)，在9℃时llI组蛤仔呼吸率显著低于其它温度组。温度为9℃、15℃、20℃、26℃时l组蛤仔排泄率平均为5．458，13．169，4．946，11．138(μgNH_3-N／h)：II组蛤仔在上述温度中排泄率平均为7．695，23．578，8．319，23．90l(μgNH_3-N／h)；III组蛤仔在上述温度中排泄率平均为11．738，27．443，15．658，35．407(μgNH_3-N／h)，蛤仔排泄率在15℃和26℃时均高于9℃和20℃。4．摄食状态与饥饿状态菲律宾蛤仔代谢率有明显不同。26℃时蛤仔静止状态呼吸率平均为0．336(m102／g干重．h)，摄食状态呼吸率平均为0．656(ml0_2干重．h)，摄食状态呼吸率比静止状态平均升高了0 32(ml0_2／g干重．h)；26℃时蛤仔静止状态排泄率平均为39．471(μgNH_3-N／g干重．h)，摄食状态排泄率平均为88．08(μgNH_3-N／g干重．h)，摄食状态排泄率比静止状态排泄率平均升高了48．6(μgNH_3-N／g干重．h)。摄食状态代谢率平均是静止状态的2～3倍。根据摄食引起的呼吸率和排泄率升高量得出每氧化产生lμgNH_3-N需0_2量平均为7．05μl。5．人工控制温度对菲律宾蛤仔代谢率有明显影响。不同大小蛤仔受温度的影响程度不同。在温度5℃、10℃、l 5℃、20℃、26℃，I组和II组蛤仔呼吸率都随着温度的升高而升高，在10℃～l5℃和20℃～26℃这二个温度变化范围内呼吸率变化最大，在20℃～26℃时I组蛤仔呼吸率变动范围为O．85～1．04(m10_2／g干重．h)、II组蛤仔变动范围为0．57～0．86(ml0_2／g干重．h)。III组蛤仔呼吸率只在5℃～l0℃时明显增高，变动范围为0．09～0．5l(m10_2／g干重．h)，在10℃～26℃范围内变化不大。I组和II组蛤仔排泄率随着温度的升高而升高，变动幅度较大，在5℃～26℃范围内其排泄率变动范围为10．32～81．53(μgNH_3-N／g干重．h)；而 III组蛤仔排泄率只在5℃～15℃时随着温度的升高而升高，其排泄率变动范围为6．75～23．77(μgNH_3-N/g干重．h)，在15℃～26℃范围内几乎不变。III组蛤仔的适温范围比I组和II组蛤仔广。菲律宾蛤仔在5℃和10℃时氧氮比变化明显，变动范围为2．76～11．44，在15～26℃时变化不大。6．菲律宾蛤仔代谢率有明显的日节律性，呈正弦曲线型变化。蛤仔夜问代谢率明显升高。I组蛤仔夜间呼吸率平均为0．867(m10_2／g干重．h)，白天呼吸率平均为O．504(m10_2／g干重．h)；II组蛤仔夜间呼吸率平均为0．438(m10_2／g干重．h)，白天呼吸率平均为0．36l(m102／g干重．h)；III组蛤仔夜间呼吸率平均为0．409(m10_2／g干重．h)，白天呼吸率平均为0．252(m102／g干重．h)。在22：00-23：00菲律宾蛤仔呼吸率最高。7．底质环境对菲律宾蛤仔的代谢率有明显影响。在饥饿状态下菲律宾蛤仔在泥沙底质中呼吸率平均为l 406(m10_2／g干重h)，在无泥沙环境中呼吸率平均为O．963(ml0_2／g干重．h)；摄食状态下菲律宾蛤仔在泥沙底质中呼吸率平均为1．59l(m102／g干重．h)，在无泥沙环境中呼吸率平均为1．115(m10_2／g干重．h)。在饥饿状态下菲律宾蛤仔在泥沙底质中排泄率平均为78．934(μgNH_3-N／g 干重．h)，在无泥沙环境巾排泄率平均为45．043(μgNH_3-N／g干重．h)；摄食状态下菲律宾蛤仔在泥沙底质中排泄率平均为87．12l(μgNH_3-N／g干重．h)，在无泥沙底质中排泄率平均为58．354(μgNH_3-N／g干重．h)。蛤仔在泥沙环境中呼吸率和排泄率都明显升高。