长白山森林土壤剖面氨基糖的分布(英文)

研究了长白山土壤剖面中3种氨基糖的垂直分布规律及其对土壤有机质库的贡献,样品采自长白山北坡3个样点(海拔分别为600m,1680m和2580m).3种氨基糖对总氨基糖的贡献为氨基葡萄糖>氨基半乳糖>胞壁酸,剖面中氨基糖的含量及氨基糖对土壤有机质的贡献,在表层土壤中随土壤剖面深度增加而增加,但在矿质层中规律不同.不同纬度的氨基葡萄糖/胞壁酸比值与氨基葡萄糖/氨基半乳糖比值不同,说明它们来源于不同的微生物种群.

长期培肥黑土微生物量磷动态变化及影响因素

长期采用两种不同量有机肥 (M2 、M4)、化肥 (NPK)方式培肥黑土 ,研究微生物量P在作物生长季动态变化 .结果表明 ,施用有机肥微生物量P显著高于施用化肥 (NPK)和不施肥 (CK) ,微生物量P分别为M48 75～ 4 7 6 8mg·kg-1,M2 3 0 2～ 37 16mg·kg-1,NPK 1 5 9～ 10 6 2mg·kg-1,CK 0 76～ 6 74mg·kg-1之间 ,波动性较大 .M4、M2 处理微生物量P最大值出现在抽雄吐丝期 ,NPK、CK处理最大值出现在大喇叭口期 ;施肥数量和种类不同所引起的黑土微生物量P的差异并未因季节变化及玉米生育时期影响而明显改变 .微生物量P的动态变化与绝大多数黑土生物、理化特性指标的动态变化没有显著的相关性 ;微生物量P与黑土生物、理化特性 (除全钾外 ) ,植物氮、磷、钾含量有极显著的正相关关系 ,与黑土含水量呈显著正相关关系 .

呋喃丹对土壤酶活性的影响

通过模拟方法,研究了呋喃丹与土壤中3种重要水解酶类—土壤脲酶、转化酶和碱性磷酸酶的关系及其影响因素.结果表明:呋喃丹加入土壤后,土壤脲酶活性最初受到抑制,随培养时间的延长,呋喃丹的生态毒性逐渐降低,并最终激活脲酶;在0.3%呋喃丹浓度范围内,土壤脲酶、碱性磷酸酶和转化酶均被激活,且部分样品的转化酶活性与呋喃丹浓度呈显著或极显著正相关,说明转化酶活性可在一定程度上表征土壤受呋喃丹污染的程度,且0.3%浓度呋喃丹的生态毒性较弱,对土壤质量及生态环境比较安全.

土壤水分状况对长白山阔叶红松林主要树种叶片生理生态特性的影响

Potted seadlings of Pinus koraiensis , Fraxinus mandshurica,Juglans mandshurica,Tilia amurensis, and Quercus mongolica ,which are five dominant species in the Korean pine broadleaf forest at Changbai mountain,were grown in different soil moistures.We designed three soil moisture scenarios:85%～100%(high water,CK),65%～85% (medium water,MW) and 45%～65% (low water,LW) of field water holding capacity.The results show that characteristics of typical drought resistance on the leaves are significantly developed.The net photosynthetic rate and water use efficiency of F. mandshurica were higher compared with CK at MW.The net photosynthetic rate and water use efficiency of other 4 tree species at CK were lower than those at MW and LW.The transpiration rate of 5 tree species responses differently to various soil water status.

土壤重金属生物淋滤修复过程中廉价碳源的筛选研究

在室内模拟实验条件下,重点研究了一步和二步生物淋滤过程中黑曲霉利用各种廉价碳源替代蔗糖产酸修复重金属污染土壤的效果。结果发现,杨树叶、桃树叶、土豆皮去除重金属效果较好。其中杨树叶对冶炼厂土壤中重金属去除率分别为Cu63.5%、Cd100%、Pb16.8%和Zn27%;桃树叶去除效果分别为Cu61.8%、Cd100%、Pb14.6%和Zn28.5%;土豆皮去除效果分别为Cu61%、Cd100%、Pb10.6%和Zn34%。廉价碳源的使用可降低污染土壤生物淋滤修复成本。

聚氨基黑10B/Nafion修饰电极上多巴胺的检测

用电化学聚合法制备了聚氨基黑10B/Nafion修饰电极,利用循环伏安法研究了多巴胺在此修饰电极上的电化学行为。在磷酸盐缓冲溶液(pH6.0)中,多巴胺在修饰电极上呈现可逆的氧化还原峰。其峰电位都随pH值的增加而负移。多巴胺氧化还原峰电流与其浓度在0.2～30μmol/L范围内呈良好的线性关系;检出限为1.0×107mol/L。实验结果表明:本修饰电极具有良好的重现性、稳定性和较强的抗干扰能力。将此修饰电极用于多巴胺注射液和小牛血清中多巴胺的检测,结果令人满意。

Solvent Vapor-Induced Self Assembly and its Influence on Optoelectronic Conversion of Poly(3-hexylthiophene): Methanofullerene Bulk Heterojunction Photovoltaic Cells

Nanoscale-phase separation of electron donor/acceptor blends is crucial for efficient charge generation and collection in Polymer bulk heterojunction photovoltaic cells. We investigated solvent vapor annealing effect of poly(3-hexylthiophene) (P3HT)/methanofullerene (PCBM) blend oil its morphology and optoelectronic properties. The organic solvents of choice for the treatment have a major effect oil the morphology of P3HT/PCBM blend and the device performance. Ultraviolet-visible absorption spectro,;copy shows that specific solvent vapor annealing can induce P3HT self-assembling to form well-ordered structure; and hence, file absorption in the red region and the hole transport are enhanced. The solvent that has a poor Solubility to PCBM Would cause large PCBM Clusters and result in a rough blend film. By combining an appropriate solvent vapor treatment and post-thermal annealing of the devices, the power conversion efficiency is enhanced.

Purification, sequencing and biological activity of polypeptide from velvet antler

The velvet antler polypeptide CNT14 was extracted and purified by gel filtration, ion exchange chromatography and RP C, which showed a single peak in HPLC chromatography and a single band in SDS-PAGE. The molecular weight measured by MALDI/TOF/MS spectrum was 1479. 9028. The polypeptide consisted mostly of Glu, Leu, Val, Pro. The amino acid sequence of the polypeptide was detected with ESI-MS/ MS, and the sequence was E-P-T-V-L-D-E-V-C-L-A-H-G-P. The experiments of biological activity of polypeptide CNT14 in vivo were carried out, and the results show that CNT14 has stimulant effects on the growth of rat HT22 cells. Then we produced the polypeptide CNT14 according the amino acid sequence by solid phase synthesis, confirmed the sequence of the polypeptide to be consistent with the amino acid sequence of polypeptide CNT14 which was separated from the velvet antler.

Synthesis of poly(epsilon-caprolactone)-b-poly(gamma-benzyl-L-glutamic acid) block copolymer using amino organic calcium catalyst

A biodegradable two block copolymer, poly(epsilon-caprolactone)-b- poly(gamma-benzyl-L-glutamic acid) (PCL-PBLG) was synthesized successfully by ring-opening polymerization of N-carboxyanhydride of gamma-benzyl-L-glutamate (BLG-NCA) with aminophenyl-terminated PCL as a macroinitiator. The aminophenethoxyl-terminated PCL was prepared via hydrogenation of a 4-nitrophenethoxyl-teminated PCL, which was novelly obtained from the polymerization of c-caprolactone (CL) initiated by amino calcium 4-nitrobenzoxide. The structures of the block copolymer and its precursors from the initial step of PCL were confirmed and investigated by H-1 NMR, FT-IR, GPC, and FT-ICRMS analyses and DSC measurements.

Poly(epsilon-capralactone)/poly(ethylene oxide) diblock copolymer .2. Nonisothermal crystallization and melting behavior

The nonisothermal crystallization behavior and melting process of the poly(epsilon-caprolactone) (PCL)/poly(ethylene oxide) (PEG) diblock copolymer in which the weight fraction of the PCL block is 0.80 has been studied by using differential scanning calorimetry (DSC). Only the PCL block is crystallizable, the PEO block with 0.20 weight fraction cannot crystallize. The kinetics of the PCL/PEO diblock copolymer under nonisothermal crystallization conditions has been analyzed by Ozawa's equation. The experimental data shows no agreement with Ozawa's theoretical predictions in the whole crystallization process, especially in the later stage. A parameter, kinetic crystallinity, is used to characterize the crystallizability of the PCL/PEO diblock copolymer. The amorphous and microphase separating PEO block has a great influence on the crystallization of the PCL block. It bonds chemically with the PCL block, reduces crystallization entropy, and provides nucleating sites for the PCL block crystallization. The existence of the PEO block leads to the occurrence of the two melting peaks of the PCL/PEO diblock copolymer during melting process after nonisothermal crystallization. The comparison of nonisothermal crystallization of the PCL/PEO diblock copolymer, PCL/PEO blend, and PCL and PEO homopolymers has been made. It showed a lower crystallinity of the PCL/PEO diblock copolymer than that of others and a faster crystallization rate of the PCL/PEO diblock copolymer than that of the PCL homopolymer, but a slower crystallization rate than that of the PCL/PEO blend. (C) 1997 John Wiley & Sons, Inc.

Food utilization of adult flatfishes co-occurring in the Bohai Sea of China

Stomach contents were examined of 4527 adult individuals of 12 flatfish species collected during the 1982 - 1983 Bohai Sea Fisheries Resources Investigation. Their food habits, diet diversity, similarity of prey taxa, trophic niche breadth and diet overlap were systematically analysed. Ninety-seven prey species belonging to the Coelenterata, Nemertinea, Polychaeta, Mollusca, Crustacea, Echinodermata, Hemichordata and fish were found and five of them were considered to be principal prey for flatfishes: Alpheus japonicus, Oratosquilla oratoria, Alpheus distinguendus, Loligo japonicus and Crangon affinis. Among the flatfishes, Paralichthys olivaceus was piscivorous, whereas Pseodopleuronectes yokohamae and Pseudopleuronectes herzensteini both had polychaetes and molluscs as their main prey groups. Pleuronichthys cornutus was classified as a polychaete-mollusc eater, with a strong preference for crustaceans. Verasper variegatus, Cynoglossus semilaevis, Eopsetta grigorjewi and Cleisthenes herzensteini ate crustaceans. Kareius bicoloratus was classified as a mollusc-crustacean eater: Cynoglossus abbreviatus, Cynoglossus joyneri and Zebrias zebra were grouped as crustacean-fish eaters. However, Z. zebra also took polychaetes and C. abbreviatus and C. joyneri preyed on some molluscs. Trophic relationships among the flatfishes were complicated, but they occupied distinctive microhabitats in different seasons and selected their specific prey items, which was favourable to the stability of the flatfish community in the Bohai Sea.

水葫芦苗(Halerpestes cymbalaris)的生长特征研究

以调查统计的方法在中国科学院海北定位站研究了高寒湿地植物水葫芦苗无性系的生长特征、形态特征以及能量分配规律.结果表明:匍匐茎只有1条的水葫芦苗最多,占35.29%,匍匐茎有4条的水葫芦苗只占 8.82%.同一水葫芦苗无性系中,随着匍匐茎数目的增多,分株数、间隔子数、茎总长和匍匐茎比节间重变小.分株一般在第一级最高,末级较低;第1条匍匐茎的间隔子较长.随水葫芦苗匍匐茎数目的增多,用于无性繁殖的分株干重比例逐渐增加,用于有性繁殖的花的干重比例下降.水葫芦苗无性系这种生长特征、形态特征以及能量分配规律是其生物-生态学特性和所处高寒湿地 生境共同决定的.