磷素活化剂对黑土磷形态及有效性影响的研究

试验研究了不同温度下活化剂对黑土各形态磷的影响,阐述了活化剂对Olsen-P影响的机制。结果显示,活化剂具有很好的增加土壤中有效磷的能力,在不同的温度条件下作用效果不同,施肥条件下,高温加速磷的固定。10℃时,3种活化剂活化能力为柠檬酸铵>腐植酸>活化剂H2,分别提高土壤Olsen-P的含量达40.93%、33.06%、23.20%;20℃时,活化能力为腐植酸>柠檬酸铵>活化剂H2,分别提高土壤Olsen-P含量达32.35%、24.89%、16.72%;30℃时,与CK相比Olsen-P含量没有明显增加。活化剂能促进各形态无机磷之间的转化,活化能力随温度升高而逐渐降低。SPSS分析结果证实,Al-P和Ca2-P是黑土有效磷的主要组分,与Olsen-P极相关;Ca8-P起负作用,而Fe-P作用效果不显著,但它们仍能通过影响Al-P和Ca2-P来间接影响Olsen-P。

沙棘与微生物联合共生体的初步研究

在盆栽实验条件下通过生物接种技术 ,对非豆科固氮树木沙棘进行联合共生体的人工构建 ,定量研究了VA菌根真菌和Frankia对沙棘生长的促进作用 ,并对VA菌根菌与Frankia之间的联合增效作用进行了探讨 .结果表明 ,双接菌VAH +HR16的促生效果最佳 ,接菌植株的株高、地径、鲜重、叶绿素含量和净光合效率分别比对照提高了 42 2 5 %、33 5 2 %、198 5 6 %、43 33%和 17 4 4 %.

沈阳地区典型绿化树种生物源挥发性有机物的排放速率

采用二次热解析仪与GC-FID联用技术对沈阳地区8种典型绿化树种生物源挥发性有机物(BVOCs)的排放速率进行了观测和研究。结果表明:银中杨和垂柳的BVOCs排放量显著高于其它6种树木,排放速率分别为97.63和18.24μg.(g.h)-1。阔叶树中银中杨、垂柳、丁香、水腊主要排放异戊二烯,排放速率分别为97.33、17.71、3.78、0.13μg·(g·h)-1,榆树、皂角、银杏主要排放柠檬烯,排放速率分别为0.60、1.64、2.00μg·(g·h)-1;而针叶树油松以排放α-蒎烯为主,排放速率为2.25μg·(g·h)-1。

新型吡唑类化合物DL-1的硝化抑制效应初探

以国内外应用较为广泛的硝化抑制剂双氰胺(DCD)为参比对象,采用室内培养方法,对新型吡唑类化合物DL-1的硝化抑制效应进行初步探讨.结果表明,DL-1对土壤中铵的氧化过程具有显著的抑制效应,前3周的硝化抑制率可达70%以上,且硝化抑制能力在第14天至28天最强.与等量DCD相比,施用量为(NH4)2SO4氮量1.0%的DL-1在14、21和28d使土壤中的NO3--N含量分别下降26.23%、33.27%和23.31%;与不加抑制剂的对照处理相比,土壤NO3--N含量则分别下降了71.12%、69.10%和55.14%.当DL-1用量为(NH4)2SO4氮量的2.0%时,土壤的硝化作用受到了更强烈的抑制,到培养第90天试验结束,土壤中的NO3--N含量始终维持在较低水平.

中国植被对全球变化反应的研究

全球变化研究是本世纪80年代兴起的跨学科、跨国界、迄今为止规模最大的国际合作研究活动,涉及到地球科学、生物科学、环境科学、天体科学及遥感技术、地理信息系统及网络化高科技技术的应用等众多的学科领域,其规模之大、持续时间之久、经费投入之多和高科技技术的广泛应用,代表着当前世界科学的发展趋势。全球变化研究是由以下三个相互独立、相互依存的计划组成:以研究气候系统中物理方面的问题为主的世界气候研究计划(WCRP),以研究地球系统中的生物地球化学循环及过程为主的国际地圈-生物圈计划(IGBP)和以了解导致全球环境变化的人类因素为主的全球环境变化的人类因素计划(HDP)。

软件模糊测试中畸形输入数据的自动构造

提出一种畸形输入数据自动构造算法。基于软件二进制补丁比对结果及目标函数调用图,设计适应值函数,对同一种群中所有个体进行评估,寻找优秀个体并遗传到子代中。实验结果表明,该算法能够生成到达或接近到达软件脆弱点的输入数据,简化逆向分析人员构造软件畸形数据的过程。

Electrochemical recognition of alkali metal ions at the micro-water 1,2-dichloroethane interface using a calix[4]arene derivative

In this paper, a calix[4]arene derivative, 5,11,17,23-butyl-25,26,27,28-tetra-(ethanoxycarbonyl)-methoxy-calix[4]arene (L), is investigated as a host to recognize alkali metal ions (Li+, Na+, K+, Rb+ and Cs+) at the interface between two immiscible electrolyte solutions (ITIES). Well-defined cyclic voltammograms are obtained at the micro- and nano-water \ 1,2-dichloroethane (W \ DCE) interfaces supported at micro- and nano-pipets.

聚合物表面的纳米力学研究

综述了近些年才开展的采用原子力显微技术，在聚合物表面进行纳米力学测量的实验方法和基本理论的进展，内容包括分子链的纳米强度测量，纳米力学各向异性的表征，表面分子间的纳米相互作用，表面形貌的纳米测量以及表面微区的纳米粘弹性研究。

Structural characterization and luminescence studies of new lanthanide(III) complexes with nicotinic and isonicotinic acid N-oxides

Four new polymeric lanthanide(III) complexes of nicotinic acid N-oxide and isonicotinic acid N-oxide have been synthesized and structurally determined. In the isomorphous compounds [(Ln(L-1)(3) (H2O)(2))(n)]. 4nH(2)O(HL1 = nicotinic acid N-oxide; Ln = Eu, 1; Ln = Er, 2) the lanthanide(III) ions form infinite double chains along the b direction through the coordination of bridging carboxylate and N-oxide groups. The chains are cross-linked through hydrogen bonds between aqua ligands and uncoordinated N-oxide groups and between aqua ligands and lattice water molecules, to form a three-dimensional network. [(Eu(L-2)(2)-(H2O)(4))(n)](NO3)(n). nH(2)O (HL2 = isonicotinic acid N-oxide, 3) has a polymeric structure in which the europium (III) ions are connected into infinite chains by pairs of syn-syn carboxylate groups. Adjacent chains are interlinked by hydrogen bonds between aqua ligands and N-oxide groups to form a layer parallel to the (100) plane, and such layers are connected by hydrogen bonds between nitrate anions and aqua ligands, and between oxide groups and lattice water molecules, into a three-dimensional network. In [(Er-2(L-2)(4)(H2O)(10))](NO3)(2). H2O, 4, dinuclear units are inter-linked into a three-dimensional network through hydrogen bonding between aqua ligands and N-oxide groups of both bidentate bridging and unidentate L-2 ligands. Factors affecting the formation of coordination chains and dinuclear units are discussed. Luminescence properties of 1 and 3 have also been studied. (C) 1998 Elsevier Science Ltd. All rights reserved.

FLOW-INJECTION ANALYSIS OF GLUCOSE AT AN AMPEROMETRIC GLUCOSE SENSOR-BASED ON ELECTROCHEMICAL CODEPOSITION OF PALLADIUM AND GLUCOSE-OXIDASE ON A GLASSY-CARBON ELECTRODE

A glassy carbon electrode (GCE) modified with palladium provides excellent electrocatalytic oxidation of hydrogen peroxide. When the electrolyte contains palladium chloride and glucose oxidase, the GCE can be modified by electrochemical codeposition at a given potential. The resulting modified surface was coated with a thin film of Nation to form a glucose sensor. Such a glucose sensor was successfully used in the flow-injection analysis of glucose with high stability and anti-poisoning ability. It gave a detection limit of 1 X 10(-7) M injected glucose, with a linear concentration range of 0.001-8 mM. There is no obvious interference from substances such as ascorbate and saccharides.

C-13 NMR CHARACTERIZATION OF SOLUBLE POLYANILINE

A high-resolution C-13 n.m.r. spectrum of soluble polyaniline in DMF-d7 solution was recorded. The assignment for the various resonance peaks in the spectrum was tentatively performed and the chain structure of polyaniline was analysed. It has been shown that the main chain of pristine state polyaniline is composed of alternating benzoid-quinoid and successive benzoid-quinoid sequences with the former being present in greater concentration. The sequence distribution is random. In addition to the benzoid-type and quinoid-type structures, there is a small amount of other structural units in the main chain.

An electrochemical DNA sensor based on electrodepositing aluminum ion films on stearic acid-modified carbon paste electrode and its application for the detection of specific sequences related to bar gene and CP4 Epsps gene

An electrochemical DNA biosensor was fabricated by immobilizing DNA probe on aluminum ion films that were electrodeposited on the surface of the stearic acid-modified carbon paste electrode (CPE). DNA immobilization and hybridization were characterized with cyclic voltammetry (CV) by using methylene blue (MB) as indicator. MB has a couple of well-defined voltammetric redox peaks at the CPE. The currents of redox peaks of MB decreased after depositing aluminum ion films on the CPE (Al(III)/CPE) and increased dramatically after immobilizing DNA probe (ssDNA/Al(III)/CPE). Hybridization of DNA probe led to a marked decrease of the peak currents of MB, which can be used to detect the target single-stranded DNA. The conditions for the preparation of Al(III)/CPE, and DNA immobilization and hybridization were optimized. The specific sequences related to bar transgene in the transgenic corn and the PCR amplification of CP4 epsps gene from the sample of transgenic roundup ready soybean were detected by differential pulse voltammetry (DPV) with this new electrochemical DNA biosensor. The difference between the peak currents of MB at ssDNA/Al(III)/CPE and that at hybridization DNA modified electrode (dsDNA/Al(III)/CPE) was applied to determine the Specific sequence related to the target bar gene with the dynamic range comprised between 1.0 X 10(-7) mol/L to 1.0 x 10(-4) mol/L. A detection limit of 2.25 x.10(-8) mol/L. of oligonucleotides can be estimated.

Probability distribution of random wave-current forces

Based on the second-order solutions obtained for the three-dimensional weakly nonlinear random waves propagating over a steady uniform current in finite water depth, the joint statistical distribution of the velocity and acceleration of the fluid particle in the current direction is derived using the characteristic function expansion method. From the joint distribution and the Morison equation, the theoretical distributions of drag forces, inertia forces and total random forces caused by waves propagating over a steady uniform current are determined. The distribution of inertia forces is Gaussian as that derived using the linear wave model, whereas the distributions of drag forces and total random forces deviate slightly from those derived utilizing the linear wave model. The distributions presented can be determined by the wave number spectrum of ocean waves, current speed and the second order wave-wave and wave-current interactions. As an illustrative example, for fully developed deep ocean waves, the parameters appeared in the distributions near still water level are calculated for various wind speeds and current speeds by using Donelan-Pierson-Banner spectrum and the effects of the current and the nonlinearity of ocean waves on the distribution are studied. (c) 2006 Elsevier Ltd. All rights reserved.

真鲷（Pagrus major）胚胎超低温损伤机理研究

鱼类胚胎由于其自身结构特征：体积大、含水量高、多室结构等，迄今超低温保存尚未成功。超低温保存过程中所造成的冷冻损伤是制约鱼类胚胎超低温保存成功与否的关键，具体表现为渗透压影响、抗冻剂毒性、冰晶损伤等。系统研究并阐明鱼类胚胎冷冻损伤机理，是成功建立鱼类胚胎超低温保存技术的基础。本论文主要针对胚胎对渗透压的耐受性、抗冻剂对胚胎的渗透性、降温速率对胚胎内外冰晶形成温度的影响等冷冻损伤机理进行了系统研究，主要研究结果如下： 1.通过检测胚胎在不同浓度人工海水（0%、25%、50%、75%、1×、2×、3×、4×，渗透压范围0~3740 mOsm/kg）中的孵化率，确定了真鲷不同发育时期胚胎对渗透压的耐受范围，以及心跳期胚胎浸泡不同时间对渗透压的耐受范围。结果显示：①真鲷2-4细胞期、原肠期、10-14体节期胚胎、心跳期和出膜前期胚胎孵化率>50%时渗透压的范围依次为：919~1391 mOsm/kg、919~1391 mOsm/kg、462 ~1391 mOsm/kg、232~1878 mOsm/kg和692~1391 mOsm/kg，表明心跳期胚胎对渗透压变化的耐受范围最广；②在不同浓度人工海水中分别浸泡10 min、30 min、1 h、5 h和10 h后，真鲷胚胎孵化率无显著变化的渗透压范围分别为0~2804 mOsm/kg、0~1878 mOsm/kg、232~1391 mOsm/kg、232~1391 mOsm/kg和919~1391 mOsm/kg；结果表明心跳期胚胎对渗透压的耐受范围随浸泡时间的延长而减小。 2.采用毛细管电泳技术检测胚胎内部DMSO的浓度，并且分析了胚胎孵化率和胚胎内部DMSO的浓度随浸泡时间变化与外部抗冻剂的关系。结果表明胚胎孵化率随胚胎外部抗冻剂溶液浓度和浸泡时间的增加而降低；胚胎内部DMSO浓度随胚胎外部抗冻剂溶液浓度和浸泡时间的增加而增加。对胚胎孵化率（y1）随抗冻剂溶液浓度（x）的变化进行一元三次多项式回归，当浸泡时间分别为10 min、30 min和60 min时，回归方程依次为：y1 = -2832.7x3 + 575.01x2 - 37.011x + 99.641（R2 = 0.9722）；y1 = 30288x3 - 16322x2 + 2077.3x + 27.603（R2 = 0.9876）；y1 = 16052x3 - 5985.2x2 - 32.696x + 119.6（R2 = 0.9124）。对胚胎内部DMSO浓度（y2）随抗冻剂溶液浓度（x）的变化进行回归，当浸泡时间分别为10 min、30 min和60 min时，回归方程依次为：y2 = 0.2584e6.7294x（R2 = 0.9876）；y2 = 0.2521e10.964x（R2 = 0.9644）；y2 = 0.4054e10.95x（R2 = 0.8954）。 3. 利用低温显微镜观察了不同降温速率（20、40、60、80、100、120℃/min）对胚胎内外冰晶形成温度的影响。胚胎外部冰晶形成温度（TEIF）随降温速率的增加显著下降，在降温速率大于80℃/min之后，TEIF随降温速率增加而降低的幅度减小；胚胎内部冰晶形成温度（TIIF）在降温速率小于80℃/min 时随降温速率的升高而降低，在降温速率大于80℃/min 时随降温速率的升高而升高；胚胎内外冰晶形成温度差值（TEIF - TIIF）在降温速率小于80℃/min时随降温速率的升高而增大，在降温速率大于80℃/min时随降温速率的升高而减小。 4. 在低温显微镜下观察了真鲷胚胎低温保存中有复活胚胎记录的保存方法在冷冻解冻过程中的冰晶形成过程，结果表明：①在冷冻过程中，玻璃化法冷冻的胚胎的内部冰晶形成温度（-53.70，-64.33℃）显著低于程序降温法（-17.51，-21.40℃）；而且在玻璃化法冷冻的胚胎内部冰晶形成温度高于外部冰晶后形成（-70.30℃），程序降温法中则相反，胚胎内部冰晶形成温度显著低于外部冰晶形成温度（-4.93，-5.00℃）；玻璃化法中，40%PG冷冻的胚胎外部溶液出现玻璃化现象，其他组均未出现；②在解冻过程中，各组均出现重结晶现象；解冻后，玻璃化法的胚胎完整率（62.82%）远高于程序降温法（9.21%）。

Zooplankton functional groups on the continental shelf of the yellow sea

Zooplankton plays a vital role in marine ecosystems. Variations in the zooplankton species composition, biomass, and secondary production will change the structure and function of the ecosystem. How to describe this process and make it easier to be modeled in the Yellow Sea ecosystem is the main purpose of this paper. The zooplankton functional groups approach, which is considered a good method of linking the structure of food webs and the energy flow in the ecosystems, is used to describe the main contributors of secondary produciton of the Yellow Sea ecosystem. The zooplankton can be classified into six functional groups: giant crustaceans, large copepods, small copepods, chaetognaths, medusae, and salps. The giant crustaceans, large copepods, and small copepods groups, which are the main food resources for fish, are defined depending on the size spectrum. Medusae and chaetognaths are the two gelatinous carnivorous groups, which compete with fish for food. The salps group, acting as passive filter-feeders, competes with other species feeding on phytoplankton, but their energy could not be efficiently transferred to higher trophic levels. From the viewpoint of biomass, which is the basis of the food web, and feeding activities, the contributions of each functional group to the ecosystem were evaluated; the seasonal variations, geographical distribution patterns, and species composition of each functional group were analyzed. The average zooplankton biomass was 2.1 g dry wt m(-2) in spring, to which the giant crustaceans, large copepods, and small copepods contributed 19, 44, and 26%, respectively. High biomasses of the large copepods and small copepods were distributed at the coastal waters, while the giant crustaceans were mainly located at offshore area. In summer, the mean biomass was 3.1 g dry wt m(-2), which was mostly contributed by the giant crustaceans (73%), and high biomasses of the giant crustaceans, large copepods, and small copepods were all distributed in the central part of the Yellow Sea. During autumn, the mean biomass was 1.8 g dry wt m(-2), which was similarly constituted by the giant crustaceans, large copepods, and small copepods (36, 33, and 23%, respectively), and high biomasses of the giant crustaceans and large copepods occurred in the central part of the Yellow Sea, while the small copepods were mainly located at offshore stations. The giant crustaceans and large copepods dominated the zooplankton biomass (2.9 g dry wt m(-2)) in winter, contributing respectively 57 and 27%, and they, as well as the small copepods, were all mainly located in the central part of the Yellow Sea. The chaetognaths group was mainly located in the northern part of the Yellow Sea during all seasons, but contributed less to the biomass compared with the other groups. The medusae and salps groups were distributed unevenly, with sporadic dynamics, mainly along the coastline and at the northern part of the Yellow Sea. No more than 10 species belonging to the respective functional groups dominated the zooplankton biomass and controlled the dynamics of the zooplankton community. The clear picture of the seasonal and spatial variations of each zooplankton functional group makes the complicated Yellow Sea ecosystem easier to be understood and modeled. (C) 2010 Elsevier Ltd. All rights reserved.