浅谈专用肥在绿色食品农业生产中的作用

浅谈专用肥在绿色食品农业生产中的作用刘子江（中国科学院沈阳应用生态研究所）中图分类号Ｓ１４３．６随着我国经济的不断发展，保护生态环境、提高人民身体健康日益引起人们的关注。其中，生产和深加工无污染、安全、优质、营养类绿色食品是其重要任务之一。１９９５～...

涕灭威对大豆田土壤线虫生物多样性的影响

利用涕灭威处理大豆田,研究土壤线虫群落结构和生物多样性的变化,共鉴定出7目12科17属的土壤线虫,其中植物寄生线虫是大豆根际土壤线虫的优势营养类群,短体属Pratylenchus,茎属Ditylenchus,小杆属Rhabditis和矛线属Dorylaimus是线虫优势属。与对照相比,除开花期因气候干旱外,涕灭威处理在大豆的各个生育期均抑制了土壤线虫总数和各营养类群的群体数量增长,尤其对植物寄生线虫抑制程度更为显著。应用多样性指数H′、成熟度指数MI、均匀度指数J′、丰富度指数SR、优势度指数l和植物寄生线虫成熟度指数PPI分析比较了处理区和对照区土壤线虫生物多样性变化规律,结果显示涕灭威处理显著降低了大豆田土壤线虫的多样性、增加了线虫的优势度指数,各生态指数较好地反映了涕灭威对大豆田土壤线虫生物多样性的干扰作用。

易旱地区褐土P、Zn形态转化特点及其与持续农业的关系

采用田间微区试验和分级提取测定的方法研究了褐土中Ｐ、Ｚｎ形态转化问题．发现褐土中Ｃａ２－Ｐ和Ｃａ８－Ｐ是转化最活跃的Ｐ素形态．而且Ｃａ８－Ｐ的流通容量很大，可超过作物需Ｐ量９倍以上；在Ｚｎ的各种形态中转化最活跃的是ＥＸ－Ｚｎ和ＣＡＲＢ－Ｚｎ，其中ＣＡＲＢ－Ｚｎ的流通容量亦很大，可超过作物需Ｚｎ量１９倍以上．Ｃａ８－Ｐ库和ＣＡＲＢ－Ｚｎ库形成了褐土中调控Ｐ、Ｚｎ养分供蓄以适应旱地水分波动的主要机构．合理施肥和培肥土壤以丰富Ｃａ８－Ｐ和ＣＡＲＢ－Ｚｎ库将有利于增强作物抵御干旱能力，提高水分养分利用效率，促使旱地农业持续向高产优质高效方向发展．

城市交通生态占用研究:以北京市为例

为了反映城市不同交通工具对自然生态环境产生的压力和影响程度,基于生态占用理论和方法,计算了2002年北京市公共电汽车、地铁、轻轨、出租车、小公共汽车和私家车等主要交通工具的生态占用.结果表明:私家车生态占用约为7.27×105hm2;出租车生态占用约为2.42×105hm2;公共电汽车生态占用约为1.59×105hm2;小公共汽车生态占用约为0.71×105hm2;地铁生态占用约为0.32×105hm2;轻轨生态占用约为0.23×105hm2.私家车的人均生态占用是公共汽车人均生态占用的5.67倍.这证实

中国能源保障水平分区初探

在经济高速增长的新形势下,能源保障风险日益凸现。全国能源保障分区研究不仅是能源风险管理的基本要求,也是经济发展对能源产业提出的新要求。本文阐述了全国能源资源的基础形势,并对1996年~2005年间我国一次能源生产和消费情况进行了分析;构建了由能源储量比、对外依存度、库存增减量、能源生产弹性系数、能源消费弹性系数、运输线路长度6个指标组成的能源保障指标体系,采用因子分析法确定各个指标的权重;并根据灰色聚类方法对全国30个省(市、区)"十五"期间的能源保障能力进行了评估与分区。结果表明:我国能源保障水平具有南

The temporal and spatial evaluation on China's agricultural policy output since 1978

Since reform and opening up, how much contribution has China's implementation of new agricultural policy made to agricultural output? This paper is trying to establish an agricultural policy output econometric model for doing a quantitative analysis of China's new agricultural policy. The results show that China's agricultural policies on agricultural output have an average contribution rate of about 7% since 1978, which is consistent with the OECD's basic forecast. There are obvious temporal and spatial differences. Generally speaking, we can divide the contribution of agricultural policy into three periods, which are the start-up phase from 1978 to 1991 (14 years), the stationary phase from 1992 to 2002 (11 years) and the rising phase from 2003 to 2008 (6 years). In space, the contribution of agricultural policy underwent a process from the all-low in the start-up phase, the gradual increase in the stationary phase to the all-high in the rising phase. Northern and western regions are more sensitive to policies. There are three major factors that can affect the contribution of regional agricultural policies, which are the process of national industrialization strategy, terrain and the level of local finance.

Synthesis and near-infrared luminescent properties of some ruthenium complexes

A series of seven ruthenium complexes with different ligands were synthesized and their optical, electrochemical and photoluminescent properties were characterized. Electroluminescent properties of these complexes were further evaluated using a light-emitting electrochemical cell with a configuration of indium tin oxide (ITO)/complex (100 nm)/Au (100 nm).

Micelle-assisted synthesis of polyaniline/magnetite nanorods by in situ self-assembly process

Polyaniline/magnetite nanocomposites consisting of polyaniline (PANI) nanorods surrounded by magnetite nanoparticles were prepared via an in situ self-assembly process in the presence of PANI nanorods. The synthesis is based on the well-known chemical oxidative polymerization of aniline in an acidic environment, with ammonium persulfate (APS) as the oxidant. An organic acid (dodecylbenzenesulfonic acid, DBSA) was used to replace the conventional strong acidic (1 M HCl) environment. Here, dodecylbenzenesulfonic acid is used not only as dopant, but also as surfactant in our reaction system.

Platinum-macrocycle co-catalysts for electro-oxidation of formic acid

In this paper, it was found that the electrocatalytic activity of a Pt electrode for the electro-oxidation of formic acid could be dramatically enhanced with the modification of macrocycle compounds, such as iron-tetrasulfophthalocyanine (FeTSPc). The electro-oxidation of formic acid on a modified Pt electrode with FeTSPc occurs mainly through a direct pathway. A series of macrocycle compounds were also investigated as modifiers and exhibited a promotion effect similar to the Pt electrode.

Blends based on sulfonated poly[bis(benzimidazobenzisoquinolinones)] and poly(vinylidene fluoride) for polymer electrolyte membrane fuel cell

A new blend system consisting of an amorphous sulfonated poly[bis(benzimidazobenzisoquinolinones)] (SPBIBI) and the semi-crystalline poly(vinylidene fluoride) (PVDF) was prepared for proton exchange membranes. The miscibility behavior of a series of blends of SPBIBI with PVDF at various weight ratios was studied by WXRD, DSC and FTIR. The properties of the blend membranes were investigated, and it was found that the introduction of PVDF in the SPBIBI matrix altered the morphological structure of the blend membranes, which led to the formation of improved connectivity channels. For instance, the conductivity of the blend membrane containing 10 wt% PVDF displayed the highest proton conductivity (i.e., 0.086 S cm(-1)) at room temperature, a value almost twofold that of the pristine SPBIBI membranes (i.e., 0.054S cm(-1)) under identical conditions.

Investigations of the properties of Mg-5Al-0.3Mn-xCe (x=0-3, wt.%) alloys

Mg-5Al-0.3Mn-xCe (x = 0-3, wt.%) alloys were prepared by metal mould casting method. The microstructures and mechanical properties were investigated. The results revealed that the main phases of as-cast Mg-5Al-0.3Mn alloy consist of alpha-Mg matrix and beta-Mg17Al12 phase. With the addition of Ce element, Al11Ce3 precipitates were formed and mainly aggregated along the grain boundaries. The amount of the Al11Ce3 precipitates increased with increasing addition of Ce, but the amount of beta-Mg17Al12 phase decreased. The highest tensile strength was obtained in Mg-5Al-0.3Mn-1.5Ce alloy. The ultimate tensile strength (UTS), yield strength (YS) and elongation at room temperature are 203 MPa, 88 MPa and 20%, separately.

Effect of cerium on microstructure and electrochemical performance of Ti-V-Cr-Ni electrode alloy

Effect of cerium on the microstructure and electrochemical performance of the Ti0.25V0.35-xCexCr0.1Ni0.3 (x = 0, 0.005) electrode alloy was investigated by X-ray diffraction (XRD), field emission scanning electron microscopy/energy dispersive X-ray spectrometry (FESEM-EDS), and electrochemical impedance spectroscopy (EIS) measurements. On the basis of XRD and FESEM-EDS analysis, the alloy was mainly composed of V-based solid solution with body-centered-cubic structure and TiNi-based secondary phase. Ce did not exist in two phases, instead, it existed as Ce-rich small white particles, with irregular edges, distributed near the grain boundaries of the V-based solid solution phase. Discharge capacity, cycle stability, and high-rate discharge ability of the alloy electrode were effectively improved with the addition of Ce at 293 K. It was very surprising that the charge retention was abnormal with larger discharge capacity after standing at the open circuit for 24 h. EIS indicated that addition of Ce improved the dynamic performance, which caused the charge transfer resistance (R-T) to decrease and exchange current density (I-0) to increase markedly. The exchange current density of the electrochemical reaction on the alloy surface with Ce addition was about 2.07 and 3.10 times larger than that of the alloy without Ce at 303 and 343 K, respectively.

CPE-g-HEA/TDI热塑性弹性体的制备和性能研究

采用氯化原位接枝法合成主链为氯化聚乙烯(CPE)、支链为丙烯酸-2-羟基乙酯（HEA）的官能化接枝聚合 物(CPE-g-HEA),制备CPE-g-HEA/2,4-二异氰酸甲苯酯（TDI）热塑性弹性体,并对其性能进行研究。结果表明, CPE-g-HEA/TDI热塑性弹性体的物理性能较好;与溶液法产物相比,共混法CPE-g-HEA/TDI热塑性弹性体的强度 较大、相对分子质量较小、相对分子质量分布较宽,热行为基本无变化;共混法CPE-g-HEA/TDI热塑性弹性体的反 应温度应控制在60～70℃,共混次数(即打三角包次数) 为150次时拉伸强度较高、80次时拉断伸长率较高,HEA/TDI摩尔比为1/0.5时拉伸强度较高。