双奇核~(172)Re高自旋态实验研究

利用149Sm(27Al,4nγ)172Re反应布居了形变双奇核172Re的高自旋态,用12套带有BGO反康普顿抑制的高纯锗探测器阵列进行了在束γ实验测量,首次建立了172Re由3个转动带构成的高自旋态能级纲图.研究和讨论了3个转动带的结构特征,基于已有的高自旋态核结构知识并通过系统学比较和分析指出它们的准粒子组态分别为πh11/2 νi13/2,πh9/2 νi13/2和 π1/2-[541] ν1/2-[521].发现前两个转动带在自旋小于18时其转动能级呈现反常的旋称劈裂.

仓鼠V79细胞对加速碳离子的辐照致死效应

分别测定了传能线密度（LET）为125．5、200、700keV／μm碳离子辐照仓鼠V79细胞的存活曲线，由存活曲线确定了上述3种碳离子辐照时V79细胞的失活截面依次为7．86±0．17、10．44±1．11、32．32±3．58μm2。以V79细胞对60Coγ射线的存活响应为参考值，给出了对应于上述3种碳离子照射周％、20％、50％、80％存活水平下的相对生物学效应（RBE），结果表明125．5keV／μm碳离子的RBE值在各个存活水平下都为最大。提示：以存活为生物学终点的RBE最大值在LET值小于200keV／μm的碳离子辐照时出现。

Inner structure of Spin(c)(4) gauge potential on 4-dimensional manifolds

The decomposition of Spin(c)(4) gauge potential in terms of the Dirac 4-spinor is investigated, where an important characterizing equation Delta A(mu) = -lambda A(mu) has been discovered. Here, lambda is the vacuum expectation value of the spinor field, lambda = parallel to Phi parallel to(2), and A(mu) the twisting U(1) potential. It is found that when), takes constant values, the characterizing equation becomes an eigenvalue problem of the Laplacian operator. It provides a revenue to determine the modulus of the spinor field by using the Laplacian spectral theory. The above study could be useful in determining the spinor field and twisting potential in the Seiberg-Witten equations. Moreover, topological characteristic numbers of instantons in the self-dual sub-space are also discussed.

Double electron processes in collisions of partially stripped ions Cq+ (q=1-4) with helium

The multi-electron processes are investigated for 17.9-120keV/u C1+, 30-323 keV/u C2+, 120-438 keV/u C3+, 287-480keV/u C4+ incident on a helium target. The cross-section ratios of double electron (DE) process to the total of the single electron (SE) and the double electron process (i.e. SE+DE), the direct double electron (DDI) to the direct single ionization (DSI) as well as the contributions of DDI to DE and of TI to DE are measured using coincidence techniques. The energy and charge state dependences of the measured cross-section ratios are studied and discussed.

小肠电离辐射损伤研究进展；Advances in Small Intestinal Ionizing Radiation Injury Research

肠道的电离辐射损伤是腹部及盆腔肿瘤放射治疗过程中的剂量限制因素。综述了小肠电离辐射损伤的临床症状、小肠上皮及粘膜下层基质改变、信号分子表达变化、组织学变化和超微结构变化。简介了中国科学院近代物理研究所重离子束辐射生物医学重点实验室正在进行的有关小肠重离子辐射损伤及防护方面的研究工作。

Molecular dynamics and control following excitation with an ultra-short intense laser pulse

Vibronic excitations of the tri-atomic molecule OClO (A(2)A(2)(nu(1), nu(2), nu(3)) <-- (XB1)-B-2 (0, 0, 0)) with weak and strong ultra-short laser fields are studied within full quantum wavepacket dynamics in hyperspherical coordinates. Different dynamics is observed following excitation with laser pulses of different intensities. With a strong laser pulse, many vibrational states are excited and a spatially more localised wavepacket arises. The numerical results show that the population of different vibrational states of the wavepacket on the excited potential energy surface is altered by the intensity of the laser pulse. The numerical results also suggest a related effect on the phase of the wavepacket. These interesting phenomena can be understood by an analysis of the corresponding results for two model diatomic molecules. The possible physical mechanisms of control of chemical processes using strong laser fields are discussed. (C) 2004 Elsevier B.V. All rights reserved.

Molybdenum containing surface complex for olefin epoxidation

Silica-supported molybdenum surface complexes were prepared by the reaction between (N=) Mo(OtBu)(3) and silica via displacement of the tert-butoxy ligands for siloxyls from the silica surface. The structure of the surface molybdenum complexes was well defined by in-situ FT-IR, elemental analysis, H-1 NMR and C-13 CP/MAS NMR techniques. The surface complexes could undergo alcoholysis reaction with CD3OD and CH3OH in the same way as free (N =) Mo(OtBu)(3) and they show high catalytic activity and selectivity in olefin epoxidation. Initial rates up to 24.9 mmol epoxide (mmol Mo)(-1) min(-1) were achieved in the epoxidation of cyclohexene using TBHP as oxidant.

旱农区不同种植模式作物最佳补灌时期和适宜补灌量研究

对不同种植模式作物进行补灌的产量及水分效应研究表明 ,在自然降雨基础上补灌 45 mm和 90 mm水 ,各种植模式的产量及水分利用效率均较对照大幅度提高。初步确定出在作物生长前期降雨较多的丰水年 ,三种种植模式的适宜补灌定额为 90 mm。三种种植模式中作物的最佳补灌时期及适宜补灌量分别为 :单作小麦播前沟灌 8mm,孕穗期补灌 82mm;单作地膜玉米在大喇叭口期一次补灌 90 mm;带田小麦播前沟灌 4mm,拔节期和孕穗期各补灌 19mm,带田地膜玉米在拔节期和大喇叭口期各补灌 2 4 mm。该结论适宜于北方旱地农田推广应用。

沈阳市建成区植被环境效益分析

以基于GIS为基础的城市植被分析软件———CITYgreen的要求对沈阳市建成区进行调查,并统计分析,获得沈阳市建成区绿色覆盖现状,各用地类型植被的环境效益以及沈阳市建成区的总体环境效益。结果表明,沈阳市建成区的绿色覆盖(树冠与草地之和)率以绿化类用地最高;植被净化效益的主体为树木覆盖,植被环境效益与树冠覆盖比呈现正相关关系,单位面积的净化效益以绿化用地最高,商业金融用地最低;建成区总碳贮存为199 485.4t,每年的碳存留为879.6478t,O3的去除量为71 283.89kg,SO2的去除量为22 163.97kg,NO2的去除量为40 876.3kg,PM10的去除量为61 494.02kg,CO的去除量为8 149.331kg。该文还对提高环境质量提出建议。

生态空间理论与景观异质性

概述生态空间理论的若干主要方面：尺度、空间格局、景观异质性、镶嵌与生态交错带以及干扰与景观动态等。生态空间理论是景观评价、管理和生态规划的重要基础，对于区域可持续发展和生物多样性保护等方面的研究都具有重要的指导意义。

生物有机肥对小油菜生长及品质的影响

在小油菜上进行施用生物有机肥、有机无机配合施肥、三元肥的田间对比试验。结果表明,单施生物有机肥比单施无机三元肥的小油菜中硝酸盐和亚硝酸盐含量分别降低36.17%和21.77%;种植后土壤中有机质比单施无机三元肥提高11.12%。油菜生产中施用生物有机肥可以提高作物品质,提高土壤有机质含量,培肥地力,与三元肥配合施用不会造成明显减产。

水肥耦合条件下春小麦叶片的光合作用

采用312-D最优饱和设计,在辽宁西部半干旱区进行了田间春小麦光合作用试验研究．结果表明:叶片光合速率与籽粒产量正相关．水肥单因子对叶片光合速率影响的大小顺序是,氮>水>磷．交互耦合作用对叶片光合速率影响的大小顺序为:氮与水耦合>氮与磷耦合>磷与水耦合．水肥耦合促进叶片光合速率提高的主要原因是:扩大了叶面积、提高了叶片蒸腾速率、增大了叶片气孔导度、提高了胞内水浓度、降低了胞内二氧化碳浓度．单叶光合速率高于7．5×10-3μmol／s的水肥优化管理方案是:施氮量为323．4-399．9 kg／hm2、施磷量为65．8-105．7 kg／hm2、灌水量为276．1-353．2 mm．