黄土丘陵区林草景观界面雨后土壤水分空间变异规律

对黄土丘陵区刺槐林-草地景观界面上雨后土壤表层(0~10 cm)和亚表层(10~20 cm)水分的空间变异规律进行了研究.经典统计学分析表明,草地两层的土壤含水量分别高于林地;林草界面两层的土壤含水量均为弱变异程度,并具有明显的生态梯度.移动窗口法分析表明,林草界面对土壤表层和亚表层的水分影响范围为边界两侧4 m、3 m,影响域分别为8 m6、m.地统计学分析表明,草地两层土壤含水量空间分布均表现为纯块金效应,林地两层均可拟合成线性模型,而林草界面两层均可拟合成球状模型;林草界面土壤表层、亚表层水分空间依赖性和空间自相关较强,其空间结构异质性明显高于林地和草地.克立格制图描述的林草界面土壤水分的空间分布格局为从边界处向两侧的一定距离范围内,土壤含水量呈条带状分布,而在较远的距离,水分的空间分布呈现出几个明显的斑块状.

Interweaving of single-helical and equal double-helical chains with the same helical axis in a 3D metal-organic framework

A novel metal-organic framework with unprecedented interweaving of coaxial single-helical and equal double-helical chains of opposite chirality, which features a super-connective helix simultaneously tangling with eight helices, was reported.

Microphase-Separated Brushes on Square Platelets in PS-b-PEO Thin Films

In polystyrene-block-poly(ethylene oxide) thin square platelets can be obtained via fast solvent evaporation by controlling the tethering density (0.08 < sigma < 0.11). The tethering density of the brushes is proportional to the thickness of the PEO crystal and increases with increasing initial solution heating temperature (T-i). When T-i < T-m, where T-m is the melting point of PEO, brushes with microphase-separated structures are observed. The formation of microphase-separated brushes depends on two factors: the strong incompatibility between PS and noncrystalline PEO chains (attached to the crystalline PEO) and the weak interaction between PS-PS brushes.

刺五加寡糖的电喷雾多级串联质谱研究

采用小柱层析法从刺五加中分离得到刺五加寡糖类系列化合物(刺五加二糖～刺五加六糖).实验结果表明, 在正离子模式下的ESI-MS谱中, 此类化合物呈现出特征的加合离子峰簇[M+Na]+/[M+K]+或[M+H2O+Na]+/[M+H2O+K]+, 可以确定其分子量; 在负离子模式下的ESI-MS谱中, 刺五加寡糖易形成[M-H]-/[M+nH2O-H]-(n<3).还利用电喷雾多级串联质谱(ESI-MSn)对刺五加三糖进行了系统的研究, 推断出刺五加三糖的组成与结构.

Processible nanostructured materials with electrical conductivity and magnetic susceptibility: Preparation and properties of maghemite polyaniline nanocomposite films

We here present a versatile process for the preparation of maghemite/polyaniline (gamma-Fe2O3/ PAn) nanocomposite films with macroscopic processibility, electrical conductivity, and magnetic susceptibility. The gamma-Fe2O3 nanoparticles are coated and the PAn chains are doped by anionic surfactants of omega-methoxypoly(ethylene glycol) phosphate (PEOPA), 4-dodecylbenzenesulfonic acid (DBSA), and 10-camphorsulfonic acid (CSA). Both the coated gamma-Fe2O3 and the doped PAn are soluble in common organic solvents, and casting of the homogeneous solutions gives free-standing nanocomposite films with gamma-Fe2O3 contents up to similar to 50 wt %. The morphology of the gamma-Fe2O3 nanoparticles are characterized by transmission electron microscopy, UV-vis spectroscopy, and X-ray diffractometry. The gamma-Fe2O3/PAn films prepared from chloroform/m-cresol solutions of DBSA-coated gamma-Fe2O3 and CSA-doped PAn are conductive (sigma = 82-237 S/cm) and superpapamagnetic, exhibiting no hysteresis at room temperature. The zero-field-cooled magnetization experiment reveals that the nanocomposite containing 20.8 wt % gamma-Fe2O3 has a blocking temperature (T-b) in the temperature region of 63-83 K.

醇溶蛋白水平上甘、青两省春小麦品种间的遗传多样性现状及演变趋势

用APAGE技术检测了43个春小麦品种在醇溶蛋白水平上的遗传变异，在计算Jaccard相似系数的基础上用UPGMA方法进行聚类分析。共得到42种不同的带型，电泳共分离出37条带，其中33条具有多态性。品种间在醇溶蛋白水平上的遗传距离变异范围很大（0.0000～0.8148），平均遗传距离GD＝0.5073。说明43个品种在醇溶蛋白编码位点上存在较大变异。聚类结果显示，除佛手麦自成一类外（GS＝0.28），地方品种和引进品种与大多数育成品种（GS＝0.46）分属不同的亚类，说明育成品种同地方品种和引进品种在醇溶蛋白编码基因上存在较大变异。育成品种间在醇溶蛋白水平上的遗传多样性程度不高，这一结果提示在这一地区进行与醇溶蛋白相关的品质育种很难在现在的育成品种间杂交的基础上取得成功。从遗传多样性的演变趋势来看，历史上以地方品种间醇溶蛋白的遗传变异程度最大（GD＝0.5455），50年代引进品种变异程度最小（GD＝0.3310）。从60～90年代，育成品种醇溶蛋白水平上的遗传多样性有一先增后减的过程，但总体上变异程度要低于地方品种，其原因与亲本单一和育种目标由高产到优质变化条件下人工选择压由弱到强有关。

企业经营系统的对象模型──资金流模型

本文阐述了大型工业企业综合自动化系统体系结构中经营管理层的对象模型（资金流模型）。首先论述了该模型在自动化体系结构中的地位和作用，然后分析了企业生产经营过程中发生的资金流，提出用借贷流程图方法表达资金流模型，并将这一方法与国际通用的借贷记帐法相联系，从而揭示了资金流模型与会计核算的内在联系．本文还对企业生产与经营活动的几个主要过程用借贷流程图进行了细化描述。

引起红土表层硅铝比值增大原因的可能性探讨

中国南方的红土风化壳，是强烈化学风化作用的产物，被认为是处于或经历了脱硅富铝化阶段。但是在红土剖面上部常常出现Si/Al或SiO2/R2O3比值不降反升的现象，给运用这一指标指示化学风化强度带来了困难。本文通过对贵州平坝、新蒲及花溪碳酸盐岩红色风化壳化学风化程度的研究，以及中国南方几种不同结晶母岩上发育的红土的化学风化强度指标的对比讨论，探讨了产生这种现象的可能性原因。

全新世亚洲季风, ENSO及高北纬度气候间的关联

着重评述全新世东亚季风与印度季风之间, 季风与厄尔尼诺/南方涛动现象之间, 以及它们与北大西洋气候变化之间关联方面的研究进展. 近年来的观测和气候代用记录显示, 在年际至轨道时间尺度上, 两季风强度变化存在反相变化关系, 它与赤道太平洋上的厄尔尼诺现象和北大西洋深层水变化之间可能有密切联系. 发生在全新世的4k 事件和8k 事件, 可能是两次严重的古厄尔尼诺事件, 集中地反映了这些重要气候变化现象和过程之间的相互作用和影响. 为了深入认识这些古气候现象之间的关系, 今后应加强亚洲季风区划及季风代用记录的对比, 加强赤道太平洋高分辨率SST 代用记录及古气候模拟研究工作.

Thermodynamic properties of ethanol and gasoline blended fuel

The heat capacities (C-p) of five types of gasohol (50 wt % ethanol and 50 wt % unleaded gasoline 93(#) (E50), 60 wt % ethanol and 40 wt % unleaded gasoline 93(#) (E60), 70 wt % ethanol and 30 wt % unleaded gasoline 93(#) (E70), 80 wt % ethanol and 20 wt % unleaded gasoline 93(#) (E80), and 90 wt % ethanol and 10 wt % unleaded gasoline 93(#) (E90), where the "93" denotes the octane number) were measured by adiabatic calorimetry in the temperature range of 78-320 K. A glass transition was observed at 95.61, 96.14, 96.56, 96.84, and 97.08 K for samples from the E50, E60, E70, E80, and E90 systems, respectively. A liquid-solid phase transition and a solid-liquid phase transition were observed in the respective temperature ranges of 118-153 and 155-163 K for E50, 117-150 and 151-164 K for E60, 115-154 and 154-166 K for E70, 113-152 and 152-167 K for E80, and 112-151 and 1581-167 K for E90. The polynomial equations of Cp and the excess heat capacities (C-p(E)), with respect to the thermodynamic temperature, were established through least-squares fitting. Based on the thermodynamic relationship and the equations obtained, the thermodynamic functions and the excess thermodynamic functions of the five gasohol samples were derived.