Age and growth of Schizopygopsis younghusbandi younghusbandi in the Yarlung Zangbo River in Tibet, China

Schizopygopsis younghusbandi younghusbandi is an endemic species whose distribution is restricted to the middle reaches of the Yarlung Zangbo River, being one of the most important commercial fishes in this area. Age and growth of 606 specimens captured between October 2002 and April 2005 were studied. The range in standard length (L) was 65.7-387.3 mm and total weight (W) was 3.3-772.0 g. The relationship between L and W was W=0.000909L(2.2493) for males and W=0.000259L(2.4781) for females. Age, determined from anal scales and lapillus otoliths, ranged from 3 to 18 years. The parameters of von Bertalanffy growth functions, estimated by back-calculated length, were L-infinity = 442.7mm L, k=0.0738 year(-1) and t(0)=-1.4 year for males, and L-infinity = 471.4mm L, k=0.0789 year(-1) and t(0)=0.2 year for females. Males and females exhibited statistically significant differences in growth. chi(2)-test indicated that von Bertalanffy growth functions could well describe the growth of S. y. younghusbandi. The longevities were 39.2 and 38.2 years for males and females, respectively. Growth inflexion points were 10.2 and 12.0 years for males and females, respectively, but 84.8% of the captures were at the smaller ages. So conservation and management schemes for this population should be considered urgently. In addition, we found that populations from the upstream of the Lhasa River, the downstream of the Lhasa River and the middle reaches of the Yarlung Zangbo River showed statistically significant differences in growth patterns.

冲绳海槽北部PC-1岩芯24 cal.kaBP 以来孢粉记录的古环境信息

东海陆架是世界上最宽阔的陆架之一，面积达770 000 km2左右。在末次冰盛期（LGM），东海海平面下降120～130 m左右，绝大部分陆架暴露出海面。而冲绳海槽是第四纪以来一直保持海洋环境的东海深海区。本文以冲绳海槽北部PC-1岩芯为材料，通过分析该孔的孢粉，加上详细的AMS 14C测年，恢复了周边地区24 cal.kaBP以来的古植被，并推测古环境和古气候变化，重点讨论了LGM时期出露大陆架上发育的植被。 PC-1孔（31°27.5′N，128°24.8′E）位于黑潮支流对马暖流东侧，水深590 m，柱长812 cm。孢粉分析按间隔8 cm取样，个别为4~6 cm，共分析了103个孢粉样品。利用9个AMS 14C数据建立年龄标尺，用Calib5.1.0软件进行年龄校正。通过相邻样品深度的线性内插获得每个样品的年龄，采用外延法得到顶部和底部的校正年龄分别为351cal aBP、24 280 cal aBP，孢粉样品的时间分辨率平均为230 a。 根据孢粉百分比和沉积率的变化，可划分出四个带：Ⅰ带（812～715 cm，24.2～21.1 cal. kaBP）、Ⅱ带（715～451 cm，21.1～15.2 cal. kaBP）、Ⅲ带（451～251 cm，15.2～10.8 cal. kaBP）、Ⅳ带（251～0 cm，10.8～0.3 cal. kaBP），分别对应MIS 3末期、末次冰盛期、冰消期和全新世。末次冰盛期草本植物花粉占优势，孢粉沉积率较高，此时草本花粉主要来源于出露的大陆架，其上发育了以蒿属为主的草地植被，气候比较寒冷干燥；冰消期海平面开始回升，松属花粉含量升高，草本植物花粉含量下降；全新世以木本植物花粉占绝对优势，栗属－栲属花粉迅速增加，蕨类孢子含量升高，草本植物花粉含量锐减，孢粉沉积率降低，由于海平面回升，大陆架被淹没，此时孢粉主要来源于日本岛，九州地区生长了以栲属、栎属为主的常绿阔叶与落叶阔叶林，气候温暖湿润。 叶枝杉属花粉在整个岩芯中零星出现。叶枝杉属植物分布于菲律宾吕宋北部至塔斯马尼亚和新西兰气候潮湿的山地林中，该属花粉在岩芯中的出现，可能暗示了黑潮的影响或者是较强的夏季风。 草本植物与松属花粉百分比变化很好的反映了海平面的升降，松属花粉含量较高指示海平面较高。对岩芯中主要类型的花粉百分比进行了频谱分析，显示存在千年尺度的准周期变化，有明显的6.8，3.8，2.2，1.6 ka的周期。 孢粉样品中的炭屑统计表明，末次冰消期炭屑含量最高，可能因为末次冰消期降雨量增加，炭屑可被降水带到沉积地点沉积下来；全新世的炭屑浓度较高，尤其在晚全新世，出现了一个峰值，究其原因可能与气候变化和人类活动有关。

gamma cross section in p plus p collisions at root s=200 GeV

We report on a measurement of the gamma(1S + 2S + 3S) -> e(+)e(-) cross section at midrapidity in p + p collisions at root s = 200 GeV. We find the cross section to be 114 +/- 38(stat + fit)(-24)(+23)(syst) pb. Perturbative QCD calculations at next-to-leading order in the color evaporation model are in agreement with our measurement, while calculations in the color singlet model underestimate it by 2 sigma. Our result is consistent with the trend seen in world data as a function of the center-of-mass energy of the collision and extends the availability of gamma data to RHIC energies. The dielectron continuum in the invariant-mass range near the gamma is also studied to obtain a combined yield of e(+)e(-) pairs from the sum of the Drell-Yan process and b-(b) over bar production.

Studies on the structure of tricyclohexyltin-2-(1,2-dithioethylene)methylene-3-oxo-5-aryl-4-pentenicate

Three title compounds were prepared and the structure of title compound 2 was characterized by IR, H-1 NMR, C-13 NMR, Sn-119 NMR spectroscopy and the crystal structure of compound 2a was determined by X-ray analysis with the final R indices[I >2 sigma (I)] R-1 = 0.0350 and R-2,R-omega = 0.0888. The crystal of compound 2a belongs to triclinic system, space group P1 with a = 1.0598(6) nm, b = 1.307 4(10) nm, c = 1.378 6(10) nm, alpha = 62.666(7)degrees, beta = 72.530(2)degrees, gamma = 80. 680(2)degrees, V = 1.618 0 nm(3), D-x = 1. 444 g (.) cm(-3), Z = 1, F (000) = 728. The bond length of Sn1-O1 is 0. 2076 nm and Sn1 . . . O2 distance is 0.301 3 nm. The coordination about the tin atom can be considered as a distorted tetrahedral. The detail values of H-1 NMR, C-13 NMR, Sn-119 NMR, (2)J(119Sn-1H) and J(119Sn-13C) were obtained. delta (119Sn) = 23.836, (2)J(119Sn-1H) = 88.0 Hz, (1)J(119Sn-13C) = 347.1 Hz, (2)J(119Sn-13C) = 45.6 Hz.

Crystal structure of mixed sodium-potassium paradodecatungstate 6-hydrate

The crystal structure of K7Na3[H2W12O42]3 . 6H(2)O was determined by X-ray crystallography,and refined to R=0.0864 based on 7024 observed reflections (I>2 sigma(I)). The crystallographic parameters are a=11.755(2), b=13.0493(3), c=16.289(3) Angstrom; alpha=77.13(3)degrees, beta=82.92(3)degrees, gamma=89.65(3)degrees, triclinic, space group, P (1) over bar, V=2416.7(8) Angstrom(3), Z=2, M-r=3330.98, D-cal=4.578Mg/m(3), F(000)=2904; mu (MoK alpha)=29.170mm(-1), T=293K. Two independent polyanions are centered respectively at 1,1,1/2 and 1/2, 1/2, 0, approximately perpendicular to each other with dihedral angle between the equatorial planes of the molecules at 96 degrees. K+ and Na+ respectively occupy the clefts of the two discrete polyanions.

A new dinuclear molybdenum(V)-sulfur complex containing citrate ligand: synthesis and characterization of K2.5Na2NH4[Mo2O2S2(cit)(2)].5H(2)O

The complex, K2.5Na2NH4[Mo2O2S2(cit)(2)]. 5H(2)O (1), was obtained by crystallization from a solution of (NH4)(2)MoS4, potassium citrate (K(3)cit) and hydroxyl sodium in methanol and water under an atmosphere of pure nitrogen at ambient temperature. The crystals are triclinic, space group , a = 7.376 (3)Angstrom, b = 14.620 (2) Angstrom, c = 14.661 (1) Angstrom, alpha = 71.10 (1)degrees, beta = 81.77 (1)degrees, gamma = 78.27(2)degrees, R = 0.0584 for 2545 observed (I > 2 sigma (I)) reflections. Single crystal structure analysis reveals that citrate ligand coordinated to molybdenum atom through two carboxylato oxygens and one deprotonated hydroxyl oxygen together with two bridging sulfur atoms and a terminal oxygen atom completes distorted coordination octahedron around each molybdenum atom. Principal dimensions are: Mo = O-t, 1.707 Angstrom (av); Mo-S-b, 2.341 Angstrom (av); Mo-O-(hydroxyl), 2.021 Angstrom (av); Mo-O(alpha-carboxyl), 2.1290 Angstrom (av) and Mo-O(beta-carboxyl), 2.268(av) Angstrom. IR spectrum is in agreement with the structure.

特提斯喜马拉雅带晚白垩世-始新世沉积源区分析及其构造意义

Tethyan Himalayan Sequence (THS) is located at the frontier of the India-Asia collision zone, which can preserve critical information about collision. This paper reports detailed petrology, geochemistry, spinels electron microprobe data, and in situ U-Pb ages and Lu-Hf isotopic data on detrital zircons from the late Cretaceous to early Eocene strata in Gyantze and Gamba area, south Tibet that provide important constraints on the early tectonic evolution of the India-Asia collision. In Gyantze, the lithic arkose in Zongzhuo mélange is characterized by, SiO2 =80.4%, Al2O3=8.6%, Na2O=1.6%, K2O=1.1%, LaN/YbN=8.90, and εNd (0) =-10.27. Spinels compositions are characterized by low TiO2 (generally <0.1%) and a Cr number mainly between 70 and 80. The largest population of detrital zircons is within the 73-169Ma range with high εHf (t) and > 500 Ma with complex εHf (t) values. The lithic arkose in Rilang conglomerate is characterized by, SiO2 =56.5%, Al2O3=15.6%, Na2O=4.7%, K2O=0.6%, LaN/YbN=5.00-5.29, and εNd (0) =1.92. Spinels of 2006T98 display high TiO2 (generally >0.2%) and a Cr number mainly between 70 and 85, other spinels are characterized by low TiO2 (generally <0.2%) and a Cr number mainly between 60 and 90. The largest population of detrital zircons is within 90-146 Ma range with high εHf (t). The lithic arkose in Jiachala formation is characterized by, SiO2 =64.6%, Al2O3=12.1%, Na2O=1.9%, K2O=1.8%, LaN/YbN=7.73-9.13, and εNd (0) =-5.52~-8.43. Spinels in the Jiachala formation have low TiO2 (generally <0.2%) and a Cr number between 39 and 88. Detrital zircons have a wide range of age distribution of 82-3165Ma with complex εHf (t). In Gamba, The quartze sandstone in Jidula formation is characterized by, SiO2=97.4%, Al2O3=0.9%, Na2O=0.03%, K2O=0.18%, LaN/YbN=18.70-21.684, and εNd (0) between -13.1~-7.4. While the lithic arkose in Zhepure formation is characterized by, SiO2=68.4%, Al2O3=7.3%, Na2O=1.15%, K2O=0.52%, LaN/YbN=6.09-8.99, and εNd(0)=-5.8~-6.3. Based on our geochemical analysis, spinles electron microprobe data, U–Pb ages and Hf isotope data for detrital zircons of the late Cretaceous-Eocene strata in Gyantze and Gamba, southern Tibet, the following major conclusions can be drawn: 1. In Gyantze, the Zongzhuo mélange was mainly derived from accretionary prism/THS of continental slop and Gangdese arc. Rilang conglomerate was totally from Gangdese arc. The Jiachala formation was derived from THS, suture zone and Gangdese arc. 2. In Gamba, the Jidula formation was from India craton, while the Zhepure formation was derived from THS, suture zone and Gangdese arc. 3. The deposite of Zongzhuo mélange and Rilang conglomerate (73-55Ma) marks the collision between India and Asia. 4. Late Paleocene-Eocene tectonic evolution is consistent with foreland basin system.

Extended self-similar scaling law of multi-scale eddy structure in wall turbulence

The longitudinal fluctuating velocity of a turbulent boundary layer was measured in a water channel at a moderate Reynolds number. The extended self-similar scaling law of structure function proposed by Benzi was verified. The longitudinal fluctuating velocity, in the turbulent boundary layer was decomposed into many multi-scale eddy structures by wavelet transform. The extended self-similar scaling law of structure function for each scale eddy velocity was investigated. The conclusions are I) The statistical properties of turbulence could be self-similar not only at high Reynolds number, but also at moderate and low Reynolds number, and they could be characterized by the same set of scaling exponents xi (1)(n) = n/3 and xi (2)(n) = n/3 of the fully developed regime. 2) The range of scales where the extended self-similarity valid is much larger than the inertial range and extends far deep into the dissipation range,vith the same set of scaling exponents. 3) The extended selfsimilarity is applicable not only for homogeneous turbulence, but also for shear turbulence such as turbulent boundary layers.

双晶晶界在高温下的热稳定性的分子动力学研究

晶界结构在高温下的热稳定性问题是一个长期争论而又未能解决的问题，其争论的焦点是：在远低于熔点的温度下，晶界结构是否发生了可观察到的无序化，即是否存在一个远低于熔点的结构转化温度。为了能澄清这一争论，本文系统地研究了晶界结构的热稳定性。为了消除相互作用势的影响和系统误差，本文首先采用Morse势和经验多体势分别对铝、铜单晶的熔化过程进行了分子动力学模拟。在平衡态下，通过计算表征结构无序化的静态结构因子、径向分布函数和单晶原子位形图，获得了铝、铜单晶的熔点，结果表明：多体势计算的铝和铜的单晶熔点更接近实验值。因此，采用经验多体势应用分子动力学方法分别模拟了铝、铜&Sigma;3、&Sigma;5、&Sigma;9、&Sigma;11、&Sigma;19、&Sigma;33六种对称倾侧双晶晶界晶界结构由有序向无序转化的过程，计算了平衡态下的表征结构无序化的静态结构因子、径向分布函数和晶界原子位形图并将多体势获得的铝、铜单晶熔点作为晶界结构转化温度的约化熔点，获得了铝、铜&Sigma;3、&Sigma;5、&Sigma;9、&Sigma;11、&Sigma;19、&Sigma;33六种对称倾侧双晶晶界结构的转化温度和熔点，结果表明：1．&Sigma;5、&Sigma;9、&Sigma;11、&Sigma;19、&Sigma;33五种对称倾侧双晶晶界均在远低于单晶熔点温度时，晶界结构发生了可观察到的无序化，而且双晶晶界结构的转变温度相差不大，双晶晶界熔点也低于单晶熔点。2．&Sigma;3晶界在温度远低于熔点时，其晶界结构没有发生可观察到的无序化；&Sigma;3晶界的转化温度与单晶熔点接近。所以，可以认为&Sigma;3晶界不存在转化温度。这是由于&Sigma;3晶界为共格孪晶，具有较低的能量。综上所述，除&Sigma;3共格孪晶外，在远低于熔点温度下，晶界结构发生了可观察到的无序化，即：存在一个远低于熔点的转化温度，此时其静态结构因子约为0.5左右；晶界结构的熔点均低于单晶熔点，此时其静态结构因子约为0.15左右。从全文模拟结果可以看出，静态结构因子、径向分布函数、晶界原子位形图三种方法在确定晶界的结构转化温度和熔点时，静态结构因子是最有效、最准确的定量方法。

Body loadings and health risk assessment of polychlorinated dibenzo-p-dioxins and dibenzofurans at an intensive electronic waste recycling site in China

This study is one of the very few investigating the dioxin body burden of a group of child-bearing-aged women at an electronic waste (e-waste) recycling site (Taizhou, Zhejiang Province) (24 +/- 2.83 years of age, 40% were primiparae) and a reference site (Lin'an city, Zhejiang Province, about 245 km away from Taizhou) (24 +/- 2.35 years of age, 100% were primiparae) in China. Five sets of samples (each set consisted of human milk, placenta, and hair) were collected from each site. Body burdens of people from the e-waste processing site (human milk, 21.02 +/- 13.81 pg WHO-TEQ(1998/g) fat (World Health Organization toxic equivalency 1998); placenta, 31.15 +/- 15.67 pg WHO-TEQ(1998/g) fat; hair, 33.82 +/- 17.74 pg WHO-TEQ(1998/g) dry wt) showed significantly higher levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurnas (PCDD/Fs) than those from the reference site (human milk, 9.35 +/- 7.39 pg WHO-TEQ(1998/g) fat, placenta, 11.91 +/- 7.05 pg WHO-TEQ(1998/g) fat; hair, 5.59 +/- 4.36 pg WHO-TEQ(1998/g) dry wt) and were comparatively higher than other studies. The difference between the two sites was due to e-waste recycling operations, for example, open burning, which led to high background levels. Moreover, mothers from the e-waste recycling site consumed more foods of animal origin. The estimated daily intake of PCDD/Fs within 6 months by breast-fed infants from the e-waste processing site was 2 times higher than that from the reference site. Both values exceeded the WHO tolerable daily intake for adults by at least 25 and 11 times, respectively. Our results implicated that e-waste recycling operations cause prominent PCDD/F levels in the environment and in humans. The elevated body burden may have health implications for the next generation.

零知识证明的两种变体与非延展性质的研究

零知识证明已经成为密码协议设计中一个非常重要的工具，它的发展也对计算复杂性的发展有着极为深远的影响。本文研究了零知识证明的两种变体和零知识证明的非延展性质。 文中所研究的零知识证明的两种变体是指Pass在EUROCRYPT'03上提出来的$n^{poly(logn)}$-模拟的证明和他在CRYPTO'03上提出来的公共参考串模型下的可否认零知识。对这两种变体，得到了如下结果： （1）基于抵抗亚指数线路的单向置换的存在性，构造了5-轮的高效并发的$n^{poly(logn)}$-模拟的知识论证系统。该方案使用了普通的$\Sigma$-协议作为工具。在EUROCRYPT'03中，使用了特殊的诚实验证者完全零知识（我们称之为完全$\Sigma$-协议）来构造4-轮$n^{poly(logn)}$-完全模拟的知识论证系统。这个构造是基于无爪函数的存在性的，并且它在并发合成下的封闭性紧紧依赖于$\Sigma$-协议的完全模拟性质。在EUROCRYPT'03的方案中，若使用普通的$\Sigma$-协议代替完全$\Sigma$-协议作为构造模块，得到的协议在并发合成下未必封闭。 （2）给出了公共参考串模型下的可否认零知识的一个正面结果，即：从$\Sigma$-协议到公共参考串模型下的可否认零知识的高效转化。由Pass给出的关于非平凡语言的公共参考串模型下的可否认零知识的轮数下界可知，该 转化取得了最优的轮效率。另外，转化前后增加的通信复杂度比较低。 关于非延展零知识，我们的工作主要是对现有的非延展的非交互零知识证明方案进行分析和简化。另外，引入了实例依赖的可验证随机函数（简写为InstD-VRF）这一新工具来构造非延展的非交互零知识协议。 得到的结果如下： （1）利用签名方案构造非延展的非交互零知识协议： 把Garay等人在EUROCRYPT'03中给出的公共参考串模型下的3-轮并发非延展零知识论证转化成了健壮的非交互零知识论证系统。一方面，与Garay的方案相比，在相同的模型下，提高了轮效率。另一方面，和现有的健壮非交互零知识方案相比，新方案中证明的长度比较短，并且归约计算的速度比较快。 （2）利用“隐藏地选取不可拷贝的集合”技术构造非延展的非交互零知识协议：对De Santis等给出的基于“隐藏地选取不可拷贝的集合”（hidden unduplicatable set selection）技术的方案做了如下简化：去掉了公共参考串中的冗余部分，缩短了公共参考串中部分随机串的长度，同时简化了两个子协议中所要证明的定理。这使得证明过程中的归约效率有所提高，同时缩短了证明的长度。 （3）利用InstD-VRF构造模非延展的非交互零知识证明：以InstD-VRF为工具，构造了比较简单的非延展的非交互零知识证明。实际上，由于InstD-VRF的构造方法有很多种，这个方案可以看成是构造非延展的非交互零知识证明的一个框架。在某种程度上，利用个框架，可以把构造高效的非延展的非交互零知识证明问题归结为构造高效的InstD-VRF的问题。

聚醚类聚合物固体电解质的研究

聚合物固体电解质是近几年来引起人们高度重视的一种新型功能材料。由于质轻、可塑性强，可加工成溥膜等特点，使它在固体电池，燃料电池，电化学元件和分离膜等方面的应用上显示了很大的优越性，尤其在全固态高能密锂电池的应用上已成为强有力的竞争者。聚合物固体电解质是一类由聚醚类主体聚合物与无机盐形成的络合物。目前研究的大多是以取环氧乙烷（PEO）为主体聚合物的各种碱金属盐络合物。研究表明，PEO是迄今为止所发现的络合能力最强的主体聚合物，与无机盐络合后高温电导率可达2 * 10~(-3)scm~(-1)，但室温下由于PEO的高结晶性阻碍了离子的迁移，电导率只有10~(-8)-10~(-7)scm~(-1)，从而使其应用范围受到局限，本工作采用共聚、交联及添加低分子增塑剂的方法制得了既具有较高室温电导率又具有良好机械加工性能的聚合物电解质。主要工作及结论如下：1、选择了带有双键的烯丙基缩水甘油醚这一单体与环氧乙烷共聚，制得了P(EO-AGE)二元共聚物。讨论了不同催化剂对产物结构和性能的影响，发现AlEt_3-H_2O-acac的催化效果较好。DSC和X-射线衍射结果表明，共聚使PEO的结晶受阻，其结晶度随着AGE含量的增大而减小。共聚物的玻璃化转变温度及溶点均较纯PEO的低。由二元共聚物和LiClO_4组成的P(EO-AGE)-LiClO_4络合物室温电导率达2*10~(-5)scm~(-1)，较纯PEO-LiClO_4体系高2-3个数量级。2、在二元共聚物的研究基础上，合成了（环氧乙烷-环氧丙烷-烯丙基缩水甘油醚）三元共聚物，P(EO-PO-AGE)。结果表明，三元共聚物具有更低的玻璃化转变温度和更多的无定形结构。P(EO-PO-AGE)-LiClO_4络合物的室温电导率达5 * 10~(-5)scm~(-1)。3、对P(EO-AGE)-LiClO_4和P(EO-PO-AGE)-LiClO_4络合物结构的研究发现，络合物在L:/O=0.20-0.125(mol)范围内呈现完全无定形的结构，当L:/O分别为0.33和0.25(mol)时，在X-射线衍射图上出现了新的结晶衍射峰。证实了组成分别为O/Li=3和O/Li=4的结晶络合物的存在。4、对P(EO-AGE)-LiClO_4和P(EO-PO-AGE)-LiClO_4络合物电导的研究表明，电导对温度的依赖性服从VTF方程：σ=AT~(-1/2)e~(-B/(T-To))，呈现典型的非晶电解质电导行为，但在50-70 ℃范围内lg(σT~(1/2)～1/(T-To)曲线出现转折。络合物电导与盐浓度的关系表现出与理论相一致的结果，即在某一盐浓度下存在一极大值，对P(EO-AGE)-LiClO_4和P(EO-PO-AGE)-LiClO_4体系，电导极大值都出现在O/Li=20处。此处，还讨论了共聚物组成，阴离子，阳离子种类及离子对对络合物电导率的影响。5、采用添加低分子增塑剂聚乙二醇（PEG400）的方法不仅提高了聚合物电解质柔顺性，使分子链段活动性增加，而且增加了体系的无定形区，为离子迁移提供了新的导电通递。增塑P(EO-PO-AGE)-LiClO_4络合物的电导随着增塑剂含量的增大而升高，60%(vol)PEG400增塑的P(EO-PO-AGE)-LiClO_4聚合物电解质膜的电导率可达10~(-4)scm~(-1)(25 ℃)。增塑的电解质膜不仅具有较高的室温电导率，而且具有良好的热稳定性，在700 ℃下无相分离；于干燥气氛下放置一年无蠕变流动现象，电导亦无变化。6、采用硫化和辐射交联法制得具有网络结构的聚合物电解质膜。交联后的电解质膜尺寸稳定性增加，拉伸强度和断裂伸长均成倍增加，抗溶剂性能提高，具有良好的可加工性。硫化交联所得的P(EO-AGE)-LiClO_4和P(EO-PO-AGE)-LiClO_4网络电解质膜的室温电导率仍可达10~(-5)scm~(-1)，而经辐射交联所得的PEG400增塑的P(EO-PO-AGE)-LiClO_4电解质膜的室温电导率可达10~(-4)scm~(-1)。交联电解质膜具有与未交联电解质膜相似的电导行为。

Characteristics of plasma induced by interaction of a free-oscillated laser pulse with a coal target in air and combustible gas

Plasma in the air is successfully induced by a free-oscillated Nd:YAG laser pulse with a peak power of 10(2-3) W. The initial free electrons for the cascade breakdown process are from the ablated particles from the surface of a heated coal target, likewise induced by the focused laser beam. The laser field compensates the energy loss of the plasma when the corresponding temperature and the images are investigated by fitting the experimental spectra of B-2 Sigma(+) -> X-2 Sigma(+) band of CN radicals in the plasma with the simulated spectra and a 4-frame CCD camera. The electron density is estimated using a simplified Kramer formula. As this interaction occurs in a gas mixture of hydrogen and oxygen, the formation and development of the plasma are weakened or restrained due to the chaining branch reaction in which the OH radicals are accumulated and the laser energy is consumed. Moreover, this laser ignition will initiate the combustion or explosion process of combustible gas and the minimum ignition energy is measured at different initial pressures. The differences in the experimental results compared to those induced by a nanosecond Q-switched laser pulse with a peak power of 10(6-8) W are also discussed. (C) 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

不同森林管理预案下友好林业局森林景观的动态变化

Knowledge about cumulative effects of forest management alternatives on forest landscape is required to make forest management decision. In this paper,a spatially explicit landscape model,LANDIS,was applied to simulate forest landscape changes in 200 years under four management alternatives (no cutting,clearcutting,selective cutting I and II) in Youhao Forestry Bureau located in Small Khingan Mountains. APACK was used to calculate distribution area of the representative species and species age cohort for six species. The results showed:1) timber harvest decreased area percentage of representative conifer species,Pinus koraiensis,Picea koraiensis and Picea jezoensis,Larix gmelinii to some extent compared to no cutting. The most influencing cutting mode for the area percentage of Tilia amurensis and Quercus mongolica was selective cutting II,followed by selective cutting I and clearcutting. To the contrast,the change of area percentage of Betula phatyphylla was contrary to the management alternatives; 2) As to species age cohort composition,timber harvest significantly changed age structure,that is,it decreased over-matured age cohort of representative species,and increased seedling and middle-age cohort (B. phatyphylla was not included,because its area percentage of over-mature age cohort was the highest under clearcutting than other three scenarios).