亚热带主要树种细根分解对土壤活性有机碳的影响

土壤有机碳是全球碳循环的重要组成部分，土壤碳库是陆地生态系统最大的碳库。在一定时间内土壤有机碳含量通常代表了植物碳输入和微生物分解之间的相对量的大小。土壤活性有机碳是土壤有机碳的一部分，土壤活性有机碳是土壤有机碳中周转速率最快的。土壤活性有机碳可以用微生物碳和水溶性有机碳等指标进行表征，它们可以较早指示土壤质量的变化。植物通过根系分泌和周转向土壤输入碳，而有关树木细根分解对土壤活性有机碳影响的文献很少。细根是植物凋落物的一部分，在物质循环中起到重要作用。 本文采用实验室培养方法，以桤木(Alnus cremastogyne)、杉木(Cunninghamia lanceolata)和火力楠(Michelia macclurei)细根为材料研究了不同树种细根、不同添加量细根以及不同培养温度对土壤活性有机碳的影响，以揭示人工林细根对土壤有机碳的影响。 第3章研究结果表明，培养结束后CO2-C累积释放量依次为：火力楠细根处理>桤木细根处理>杉木细根处理，添加细根的处理土壤微生物碳和水溶性有机碳含量均显著高于对照，而土壤全碳含量只在添加火力楠细根处理下显著高于对照，结果表明细根可以在短时间内提高土壤活性有机碳的含量。 第4章研究了不同细根量对土壤活性有机碳的影响，结果表明同一树种细根不同添加量对土壤全碳的影响程度不同，土壤全碳随着细根添加量的增加而显著增加。各树种均以添加2.0g细根处理的土壤微生物碳含量最高。各树种细根不同添加量的处理对土壤水溶性有机体碳的影响均不显著。培养结束时土壤硫酸钾浸提溶解性有机碳含量变化不大，只有杉木细根0.6g处理土壤硫酸钾浸提有机碳含量显著高于0.3g处理，其他处理间差异不显著。 第5章研究了不同温度对土壤活性有机碳的影响，结果表明温度显著影响细根的分解速率，温度对土壤微生物碳没有产生显著影响，而对土壤可溶性有机碳含量的影响达到了显著水平。

长白山阔叶红松林主要树种对水分胁迫的生理生态响应

本文系统研究了长白山阔计卜红松林主要树种红松、水曲柳、胡桃揪和锻树在模拟水分胁迫下的生理生态变化。研究表明：（l）土壤水分胁迫对供试树种的生比清况有显：影响。在轻度水分胁迫下（Mw），红松和水曲柳的地下生物量／地上生物量值比对照组（CK）高，而胡桃揪和锻树的地下生物燮／地上生物量比对照组（CK）低。在重度水分胁迫下（LW），供试树种中只有红松的地下生物量／地上生物量比对照组高。（2）土壤水分胁迫对供试树种的生理生态指标有显著影响。在轻度水分胁迫下（Mw），红松和水曲柳的光合速率和水分利用效率比对照组（CK）高，胡桃揪和锻树的光合速率和水分利用效率比对照组（CK）低。在重度水分胁迫下（LW）供试树种的光合速率和水分利用效率都比对照组低。（3）在正常水分条件下（CK），水曲柳光合速率曰变化呈单峰曲线，轻度（Mw）和重度水分胁迫（LW）下均呈"双峰"曲线。正常水分条件下（C）水分利用率的日变化呈双峰曲线，轻度和重度水分胁迫下呈现波动趋势，无明显的波峰和波谷。（4）水曲柳的光合速率和水分利用效率与各因素间多元线性回归的结果表明，三种水分处理下的蒸腾速率、气温、叶温、气孔导度、胞间CO2浓度、光合有效辐射均对光合速率，水分利用效率有一定影响，但影响程度有所差别。（5）土壤水分胁迫对水曲柳、胡桃揪和锻树的初始荧光（Fo）、可变荧光（Fv）、最大荧光（Fm）的影响不大，但却显著影响各树种的PSII原初光能转换效率（Fv／Fm）和PSII潜在活性（Fv/Fo）。（6）土壤水分胁迫影响供试树种几！中的养分含量，但影响程度是不同的，水分胁迫对磷、钾素含量的影响比对氮的大。土壤水分亏缺对各树种叶中的Ca元素无显著影响。红松、胡桃揪和极树叶片中的Mg含量随着土壤水分胁迫的加重也随之逐渐减小，但水曲柳在轻度水分胁迫下叶中的Mg含量最高，关于这一现象还有待以后开展深入的研究。

30Mev/u~40Ar+~natAg轻粒子与复杂碎片的测量

利用气体探测器和CsI望远镜探测器测量了30MeV/u 40Ar+natAg反应中出射的轻粒子、中等质量碎片和重碎片。中能区轻粒子和中等质量碎片的发射成分与角度和碰撞参数有关。在前角区粒子和碎片主要来自于弹核碎裂，其平行动量分布宽度满足Goldhaber公式。提取的动量分布约化宽度σ0≈76MeV/c；在后角区轻粒子和中等质量碎片主要来自于类靶平衡热核的蒸发。利用单源模型能很好地拟合其发射能谱，由α粒子能谱提取的核温度约为4.2MeV；同时利用He/Li同位素比的方法得到的核温度约为4.6MeV。

残茬和施肥管理及犁耕对土壤碳的影响

CO2 的迅速增加 ,引起了全球温室效应。为了探讨农业活动给全球气候变化带来的负面影响 ,美国学者D .C .Reicoskh等在美国明尼苏达州莫罗斯附近利用低肥 -青料、高肥 -青料、低肥 -玉米、高肥 -玉米及无肥 -玉米试验对比 ,评估在犁耕条件下对 30a的玉米连作地土壤C的影响。试验表明 ,除对照外 ,4种处理间犁耕后 2 4h内CO2 的累计损失量差异不明显。施肥处理对 30a后土壤全C、有机C、全N和C/N没有影响。在高肥 -玉米处理中 ,尽管累计施加了 2 4 1t/hm2 秸秆 ,但其土壤中总的有机C与没有施加秸秆的高肥 -青料处理差异不显著。犁耕能够引起土壤的快速排气 ,掩盖了肥料和残茬对土壤有机C的影响 ,而仅表现出犁耕对土壤有机C的影响。结论是无论采用何种农业措施 ,只要采用犁耕方式 ,土壤有机C的下降就不可避免 ,说明土壤是CO2 的源。

Efficient red organic light-emitting diode sensitized by phosphorescent Ir compound

The efficiencies of red organic light-emitting diode (OLED) using tris-(8-hydroxy-quinoline)aluminum (Alq(3)) as host and 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) as dopant were greatly increased by adding a small amount (0.3 wt%) of Ir compound, iridium(III) bis(3-(2-benzothiazolyl)-7-(diethylamino)-2H-1-benzopyran-2-onato-N-',C-4) (acetyl acetonate) (Ir(C6)(2)(acac)), as a sensitizer

Separation of ethyl acetate-ethanol azeotropic mixture using hydrophilic ionic liquids

The separation of ethyl acetate and ethanol (EtOH) is important but difficult due to their close boiling points and formation of an azeotropic mixture. The separation of the azeotropic mixture of ethyl acetate and EtOH using the hydrophilic ionic liquids (ILs) 1-alkyl-3-methylimidazolium chloride (alkyl = butyl, hexyl, and octyl) ([C(n)mim]Cl, n = 4, 6, 8) and 1-allyl-3-methylimidazolium chloride and bromide ([Amim]Cl and [Amim]Br) has been investigated. Triangle phase diagrams of five ILs with ethyl acetate and EtOH were constructed, and the biphasic regions were found as follows: [Amim]Cl > [Amim]Br > [C(4)mim]Cl > [C(6)mim]Cl > [C(8)mim]Cl. The mechanisms of the ILs including cation, anion, and polarity effect were discussed.

Separation of ternary systems of hydrophilic ionic liquid with miscible organic compounds by RPLC with refractive index detection

A rapid and simple analytical method was developed for the simultaneous and quantitative determination and separation of hydrophilic imidazolium ionic liquids (ILs) (1-butyl-3-methylimidazolium chloride, [C(4)mim]Cl; 1-hexyl-3-methylimidazolium chloride, [C(6)mim]Cl; 1-octyl-3-methylimidazolium chloride, [C(8)mim]Cl; 1-allyl-3-methylimidazolium chloride, [Amim]Cl; or 1-allyl-3-methylimidazolium bromide, [Amim]Br) with miscible ethyl acetate and EtOH and their mixtures using reverse phase liquid chromatography coupled with refractive index detection (RPLC-RI). The influence of 60 to 100% (volume percentage) methanol in the mobile phase on the IL systems ([C(4)mim]Cl, [C(6)mim]Cl, [C(8)mim]Cl, [Amim]Br, or [Amim]Cl)-ethyl acetate-EtOH was investigated.

Silica Materials Doped with Bifunctional Ionic Liquid Extractant for Yttrium Extraction

Two new silica-based organic-inorganic hybrid materials (B104SGs and O104SGs) doped with a binary mixture of imidazolium and phosphonium ionic liquids have been synthesized and used as sorbents in batch system for rare earths (RE) separation. Imidazolium ionic liquids 1-butyl-3-methylimidazolium hexafluorophosphate (C(4)mim(+)PF(6)(-)) or 1-octyl-3-methylimidazolium hexafluorophosphate (C(8)mim(+)PF(6)(-)) acted as porogens to prepare porous materials and additives to stabilize extractant within silica gel.

In Situ Scanning Tunneling Microscopy on the Dynamic Process of the Replacement of Coronene on Au (111) by 6-Mercapto-1-Hexanol

The replacement of coronene monolayer on Au (111) by 6-mercapto-1-hexanol (MHO) was studied by in situ scanning tunneling microscopy (STM) in solutions. It was found that the rate of replacement depends strongly on the concentration of MHO. The replacement finished within a second at a higher concentration of MHO. At a lower concentration, the slow replacement could be followed by in situ STM. The replacement occurred initially near the elbow position of reconstructed Au (111) with the formation of pits in a single or several missing molecules. With the proceeding of replacement, these small pits expanded, and the surrounding coronene molecules were gradually substituted by MHO, which developed into ordered domains within a spatial confined environment. Meanwhile, the reconstruction of Au (111) was lifted. The replacement expanded fast along the reconstruction lines in the domain. For the fast replacement, a (root 3 x root 3) R30 degrees adlattice was observed, while a c(4 x 2) superlattice was observed for the slow replacement.

Phase diagram data for several salt plus salt aqueous biphasic systems at 298.15 K

Phase diagrams corresponding to aqueous biphasic systems of salt (the organic ionic liquid of salts [C(4)mim]Cl, [C(6)mim]Cl, and [C(8)mim]Cl) + salt (K3PO4, K2CO3) + water were determined at 298.15 K. The binodal curve was fitted to the Merchuk equation. Tie lines assigned from mass phase ratios according to the lever arm rule were satisfactorily described using the Othmer-Tobias and Bancroft equations.

Syntheses and crystal structures of mononuclear rhodium hydrido complexes from the reactions of [Rh(H)(2)(PPh3)(2)(EtOH)(2)]ClO4 with various nitrogen ligands

Reactions of the Rh hydrido complex [Rh(H)(2)(PPh3)(2)(EtOH)(2)]ClO4 (1) With nitrogen ligands such as 2-(4-thiazolyl)benzimidazole (tbz). pyridazine (pdz), imidazole (im) and pyrimidine (pmd) in CH,Cl, afforded Various mononuclear Rh hydrido complexes, [Rh(H)(2)(PPh3)(2)(tbz)]CIO4 (2), [Rh(H)(2)(PPh3)(2)(pdZ)(2)]ClO(4)(.)2CH(2)Cl(2) (3). [Rh(H)Cl(PPh3)(2)(pdz)(2)](ClO4CH2Cl2)-C-. (4). [Rh(H)(2)(PPh3)(2)(im)(2)]ClO(4)(.)2CH(2)Cl(2) (5). [Rh(H)Cl(PPh3)(2)(im)(2)](ClO4CH2Cl2)-C-. (6). [Rh(H)(2)(PPh3)(2)(pmd)(2)](ClO4CH2Cl2)-C-. (7) and the Rh non-hydrido complex [RhCl2(pmd)(4)]ClO4 (8). The Rh complexes 2. 3, 5 and 6 were crystallographically characterized. The formation process was monitored by H-1 NMR and UV-Vis spectra. In all the Rh hydrido complexes, the Rh atom is coordinated by two PPh3. ligands in trans-positions and two nitrogen ligands in the cis-positions. The remaining sites Lire occupied by one or two hydride atoms to form a saturated 18-electron framework in a slightly distorted octahedral geometry. For complex 2 an appreciable inter-molecular pi interaction is observed between planes of tbz and PPh3 ligands, while an intra-molecular hydrogen bonding interaction between C-H and Cl atoms is found in complex 6.

利用~1H-核磁共振谱计算环化丁苯橡胶的环化度和溶剂参与量

对环化丁苯橡胶的1 H 核磁共振谱进行了归属分析 ,并推导出计算环化度和溶剂参与量的公式。设环化丁苯橡胶的1 H 核磁共振谱图中化学位移为 7 0 ,5 4,4 9和 3 0～ 0处的峰强度分别为A ,B ,C和D ,则环化丁苯橡胶中丁二烯总物质的量 (X) =(B +C +D - 2A) /7 1 ,未环化的丁二烯物质的量 (Y) =B/2 +C/4,参与反应的二甲苯物质的量 (Z) =( 1 7 5A -B -C -D) /46 5,环化度 (P) =1 -Y/X ,溶剂参与量 (W ) =91 6Z/X。

Eu(Ⅲ)、Tb(Ⅲ)双酞菁配合物的合成及其LB膜的荧光性

合成了八-4-（正壬氧基）酞菁铽（Ⅲ）（A）、八-4-（四氢糠氧基）酞菁（Ⅲ）（B）、双酞菁铽（Ⅲ）（C）、八-4-硝基酞菁铽（Ⅲ）（D）,并通过元素分析、红外光谱、质谱和紫外.可见光谱加以确认。配合物B的π-A曲线表明它有很好的成膜性,Y型沉积形成的LB膜材料有很强的荧光响应,随着LB膜厚度的增加,荧光性增强掺杂邻菲咯啉形成的混合LB膜,其荧光性比纯膜强。n（配合物B）：n（邻菲咯啉）＝1：10时有最好的荧光行为.

Structure and order of the discotic compound 2,3,6,7,10,11-hexakispentyloxytriphenylene as revealed by diffraction and molecular simulation studies

The aggregate structure of the discotic compound 2,3,6,7,10,11-hexakispentyloxytriphenylene (HPT) was studied both for the crystalline state and the liquid crystalline state by using electron crystallography and a molecular simulation approach. In the crystalline state, HPT was found to adopt an orthorhombic P-2212 space group with cell parameters a = 36.73 Angstrom, b = 27.99 Angstrom and c = 4.91 Angstrom. Molecular packing calculations were conducted to elucidate the molecular conformation and mutual orientational characteristics in the different states. Phase transitions and relationships are discussed from a structural point of view.

RELATIONSHIP BETWEEN CONFORMATION OF TASTE COMPOUNDS AND THEIR ACTIVITIES

The conformation analysis and study on structure-taste relation-ships of 4 taste compounds have been performed, the results reveal that the sweetnees will decrease with the increase of the specific dihedral angle O-1-C-2-C-3-C-4, and the mechanism was intepreted.