Synthesis and high efficiency green light-emitting diode of a soluble polymer

A soluble polymer emitting green color with high efficiency was synthesized. Bright green electroluminescence devices, both single layer and multilayer, were fabricated. The luminous efficiency was improved dramatically. Carrier injection from the electrodes to the emissive layer and concomitant green electroluminescence from the emissive layer were observed. A luminance of 920 cd/m(2) and luminous efficiency of 5.35 1m/W were achieved at a drive voltage of 15 V for the multilayer device. (C) 1997 Elsevier Science S.A.

CHEMICAL-IONIZATION MASS-SPECTROMETRY OF SOME NITRO-CONTAINING BIFUNCTIONAL AROMATIC-COMPOUNDS - LOCATION OF PROTONATION SITE

It is found that the nitro substituent of some aromatic bifunctional compounds shows unusual reactivity towards protonation. In the chemical ionization mass spectra of nitrobenzoic acids and their esters and amides, and of nitrophenols and their ethers, protonations on the carboxyl, ester, amide, hydroxyl or alkoxyl groups are highly suppressed by that on the nitro group. As a result, fragmentations based on protonation on these groups unexpectedly become negligible. Ortho effects were observed for all the ortho isomers where the initial protonation on the nitro group is followed by an intramolecular proton transfer reaction, which leads to the expected 'normal' fragmentations. Protonation on the nitro substituent is much more favourable in energy than on any of the other substituents. The interaction of the two substituents through the conjugating benzene ring is found to be responsible for this 'unfair' competitive protonation. The electron-attracting nitro group strongly destabilizes the MH+ ions formed through protonation on the other substituent; although the COR (R = OH, OMe, OEt, NH2) groups are also electron-withdrawing, their effects are weaker than that of NO2; thus protonation on the latter group produces more-stable MH+ ions. On the other hand, an electron-releasing group OR (R = H, Me, Et) stabilizes the nitro-protonated species; the stronger the electron-donating effect of this group the more stable the nitro-protonated ions.

Toxicity and protective efficiency of cryoprotectants to flounder (Paralichthys olivaceus) embryos

With the purpose of finding an ideal cryoprotectant or combination of cryoprotectants in a suitable concentration for flounder (Paralichthys olivaceus) embryo cryopreservation, we tested the toxicities, at culture temperature (16 degrees C), of five most commonly used cryoprotectants-dimethyl sulfoxide (Me2SO), glycerol, methanol (MeOH), 1,2-propylene glycol (PG) and ethylene glycol (EG). In addition, cryoprotective efficiency to flounder embryos of individual and combined cryoprotectants were tested at -15 degrees C for 60 min. Five different concentrations of each of the five cryoprotectants and 20 different combinations of these cryoprotectants were tested for their protective efficiency. The results showed that the toxicity to flounder embryos of the five cryoprotectants are in the following sequence: PG < MeOH < Me2SO < glycerol < EG (P < 0.05); whereas the protective efficiency of each cryoprotectant, at -15 degrees C for a period of 60 min, are in the following sequence: PG > Me2SO approximate to MeOH approximate to glycerol > EG (greater symbols mean P < 0.05, and approximate symbols mean P > 0.05). Methanol combined with any one of the other cryoprotectants gave the best protection, while ethylene glycol combined with any one of the other cryoprotectants gave the poorest protection at -15 degrees C. Toxicity effect was concentration dependent with the lowest concentration being the least toxic for all five cryoprotectants at 16 degrees C. For PG, MeOH and glycerol, 20% solutions gave the best protection at -15 degrees C; whereas a 15% solution of Me2SO, and a 10% solution of EG, gave the best protection at -15 degrees C. (c) 2004 Elsevier Inc. All rights reserved.

Comparative studies on the efficiency of energy transfer of two R-phycoerythrin-C-phycocyanin conjugates constructed from sodium periodate and glutaraldehyde respectively

The C-phycocyanin and the R-phycoerythrin were purified from the blue-green alga Spirulina platensis and red alga Polysiphonia urceolata respectively. Both sodium periodate and glutaraldehyde are effective coupling agents being capable of constructing the R-phycoerythrin-C-phycocyanin conjugate, which was also called phycobiliproteins energy transfer model. The two artificial conjugates constructed with different methods were purified by Sephadex G-200 chromatography respectively. Spectra analysis indicated that energy transfer occurred in the two conjugates. The conjugate with sodium periodate had the higher efficiency of energy transfer than that with glutaraldehyde conjugate.

Zoospores of Undaria pinnatifida: their efficiency to attach under different water velocities and conjugation behavior during attachment

In the invading course of Undaria pinnatifida, zoospore attachment in a dynamically changed subtidal water environment is crucial for the establishment of a potential population in alien waters. Among many abiotic factors that may interfere with the attachment process, water velocity is the most important one. In this investigation, the effect of water velocity on zoospore attachment of U. pinnatifida was investigated in an artificially designed system. It was found that freshly released zoospores that were transported by water flowing at 0 similar to 16 cm/s showed no difficulty in attaching the smooth surface. Zoospore attachment decreased at elevated water flowing rates. At 70 cm/s no spore attachment occurred. Spores that have settled on glass slide for up to I h could not be stripped away by flowing water at a rate of 129 cm/s, the same was true of the 20 d old filamentous gametophytes. It was found that more than 70% of free-swimming zoospores tended to settle down adjacent to the settled spores and formed conjugated clusters from two up to a few hundred cells in still culture.

Evaluation of 28 marine algae from the Qingdao coast for antioxidative capacity and determination of antioxidant efficiency and total phenolic content of fractions and subfractions derived from Symphyocladia latiuscula (Rhodomelaceae)

The extracts obtained from 28 species of marine algae were evaluated for their antioxidant activity (AA) versus the positive controls butylated hydroxytoluene (BHT), gallic acid (GA), and ascorbic acid (AscA). Most of the tested samples displayed antioxidant activity to various degrees. Among them, the extract of Symphyocladia latiuscula exhibited the strongest AA, which was comparable to BHT, GA, and AscA in radical scavenging activity, as shown in the DPPH (alpha,alpha-diphenyl-beta-picrylhydrazyl) assay, and higher than those of the positive controls in beta-carotene-linoleate assay system. In addition, the ethyl acetate-soluble fraction isolated from the crude extract of S. latiuscula exhibited the highest antioxidant activity in both assay systems. This fraction was further fractionated into seven subfractions (F1-F7) by vacuum liquid chromatography (VLC). F1 and F4 were found to be the most effective subfractions in scavenging DPPH radical assay and in the beta-carotene-linoleate assay, respectively. The total phenolic content (TPC) and reducing power (RP) for all of the extracts, fractions, and subfractions (F1-F7) were also determined. The TPC of the 28 extracts ranged from 0.10 to 8.00 gallic acid equivalents (mg/g seaweed dry weight) while the RP ranged from 0.07 to 11.60 ascorbic acid equivalents (mg center dot g(-1) seaweed dry weight). Highly positive relationships between AA and TPC as well as between AA and RP were found for the extracts and fractions, while for the subfractions F1-F7 only weak or no such relations were found. The results obtained from this study indicate that further analysis is needed of those marine algal species that contain the most antioxidant activity in order to identify the active principles.

红毛菜发育过程及其生理基础

红毛菜（Bangia Lyngb.）属于红藻门，与紫菜属同属红毛菜科，其味道和营养都优于紫菜。目前红毛菜栽培产业已在我国福建莆田展开，但栽培技术还有待提高。海藻栽培技术的发展和成熟依赖于对其生长发育过程的认识。本研究针对红毛菜发育过程及相关光合生理展开，并初步探讨了一采自山西娘子关泉淡水红毛菜群体（FWB）的系统地位。 色素突变标记的壳孢子萌发特征表明最初两次分裂产生的4细胞决定了完整植株的形态建成。成熟植株，为雌雄异体。雌性生殖器果胞的标志性分化结构为原始受精丝，环境因子是促发原始受精丝发展的外部因素，其膨大程度随受精的延迟而增大。原孢子是主要的无性生殖孢子类型，在不良环境中，藻体也会形成内生孢子或休眠包囊，或者藻体断裂后重新形成完整的植株。 红毛菜的生长发育很大程度上受环境因子的控制。高温不利于配子体的发育，15-20 ºC比较适宜。红毛菜无性繁殖的最适温度-光照组合为20 ºC-8 h，有性繁殖为15 ºC-12h。 不同发育阶段，PSII实际光合效率（Y(II)）与细胞的健康状况以及光合器官完整性及其在细胞内的分布有关，而与细胞的类型关系不大。健康的假根细胞、已分化未成熟的精子以及果孢子细胞均具有很高的Y(II)。色素体由中间位变为围周位，中央大液泡（营养藻丝）和大小纤维囊泡（成熟孢子与精子）的产生，使得细胞Y(II)降低。刚放散的壳孢子Y(II)很低，说明在壳孢子由贝壳基质释放到自由水体过程，光合作用受到一定程度抑制；而2h后，Y(II)开始恢复，rbcL的转录水平非常高，为孢子的萌发储备物质和能量需求。 在失水和低盐胁迫下，藻体均维持较高的Y(II)。干出处理至藻体重量不再变化，复水后Y(II)可回复初始水平。海生红毛菜在100％淡水培养基中（约20ºC）培养7天后，部分雄性藻体依然活着。从而体现了红毛菜位居高潮带的生理优势。 FWB终生行无性繁殖，藻体形态与发生以及染色体数目（4条）与海生群体没有区别。而rbcL-rbcS Spacer序列显示，红毛菜海生群体（无性和有性）具有完全相同的序列，而FWB与它们有5bp差异，但是与欧洲、北美地区的淡水群体仅1bp不同，初步说明所有淡水红毛菜群体具有共同的原始起源。

Feeding level-scaled retention efficiency, growth and energy partitioning of a marine detritivorous fish, redlip mullet (Liza haematocheila T. & S.)

The effects of feeding level on growth, retention efficiency, faeces production and energy partitioning of redlip mullet were studied. A practical diet was used and fed at six levels from starvation, 1%, 2%, 3%, 4% of body weight (BW) to satiation for 3 weeks. The temperature was kept at 24 +/- 1 degrees C. Reducing the feeding amount resulted in significantly lower weight gain, and retention efficiency was significantly affected by feeding levels and attained the maximum at maximum feeding intake. Feeding 2% BW was the minimum required for fish to maintain growth. Fish carcass composition under different feeding levels could be divided into three groups: (1) starvation and FL1; (2) FL2 and FL3 and (3) FL4 and satiation, with significant differences among the groups but no differences in the groups except that ash content remained at constant value. Body composition of fish of group 2 was close to initial fish. The thermal-unit coefficient was 0.0381 at satiation, and significantly increased with increasing feeding levels. In order to accurately estimate basal metabolism (HeE), another trial on the relationship between HeE (kJ) and BW (g) was carried out. An exponential curve as HeE=0.1255BW(0.8386) explained this relationship. Intake energy (IE) increased from 11.30 to 63.08 kJ per fish, matching with different feeding levels. Energy allocated to growth of IE decreased with reducing feeding amount. There was a linear relationship between metabolism energy and retention energy in percentage.

Grey interrelation analysis to assess the influence of elements on the galvanic efficiency of Al sacrificial anode

Grey interrelation analysis method was used to study the correlation of Al-anode elements and its galvanic efficiency at 20 degreesC, 40 degreesC and 60 degreesC. Twenty-eight kinds of Al-anodes were made for experiments by the method given by Chinese National Standard GB4948-85 [1] and the correlation degree of elements added in the anodes were calculated. The results showed that the order of elements affecting galvanic efficiency at different temperature is basically the same, and the correlation degree can reflect the variation of Al-anode galvanic efficiency when changing temperature. It is suggested that the elements being added in Al-anode are Zn, In, Ga, Mg.

Effects of vegetation control on ecosystem water use efficiency within and among four grassland ecosystems in China

Through 2-3-year (2003-2005) continuous eddy covariance measurements of carbon dioxide and water vapor fluxes, we examined the seasonal, inter-annual, and inter-ecosystem variations in the ecosystem-level water use efficiency (WUE, defined as the ratio of gross primary production, GPP, to evapotranspiration, ET) at four Chinese grassland ecosystems in the Qinghai-Tibet Plateau and North China. Representing the most prevalent grassland types in China, the four ecosystems are an alpine swamp meadow ecosystem, an alpine shrub-meadow ecosystem, an alpine meadow-steppe ecosystem, and a temperate steppe ecosystem, which illustrate a water availability gradient and thus provide us an opportunity to quantify environmental and biological controls on ecosystem WUE at different spatiotemporal scales. Seasonally, WUE tracked closely with GPP at the four ecosystems, being low at the beginning and the end of the growing seasons and high during the active periods of plant growth. Such consistent correspondence between WUE and GPP suggested that photosynthetic processes were the dominant regulator of the seasonal variations in WUE. Further investigation indicated that the regulations were mainly due to the effect of leaf area index (LAI) on carbon assimilation and on the ratio of transpiration to ET (T/ET). Besides, except for the swamp meadow, LAI also controlled the year-to-year and site-to-site variations in WUE in the same way, resulting in the years or sites with high productivity being accompanied by high WUE. The general good correlation between LAI and ecosystem WUE indicates that it may be possible to predict grassland ecosystem WUE simply with LAI. Our results also imply that climate change-induced shifts in vegetation structure, and consequently LAI may have a significant impact on the relationship between ecosystem carbon and water cycles in grasslands.

一种基于神经网络的视觉定位系统

本文提出了一种基于人工神经网络的多线阵相机系统标定与 3D定位方法 ,并应用于基于多线阵相机构成的视觉空间定位系统 .该视觉定位系统利用了线阵相机的快速性与高分辨率的特点 ,非平行空间投影面相交定位的基本原理 ,实现了这种结构下快速、高精度空间定位 .实验表明 ,人工神经网络的定位方法简化了多线阵视觉定位系统标定与定位计算的复杂性 ,在定位精度上达到了良好效果 .为机器人位置反馈控制提供了有效的技术途径

基于立体视觉的移动机器人自主导航定位系统

描述了一种基于立体视觉的移动机器人自主导航定位系统。该系统采用双目立体视觉完成环境特征的 3D信息提取 ,实时计算出机器人相对作业目标的位姿 (6D)关系 ,导引移动机器人控制系统按目标导向进行运动。系统在相对位姿计算中采用旋动(Screw)理论 ,将带约束的多变量函数的非线性优化问题转化为线性方程组的最小二乘问题 ,简化了计算复杂性。实验表明 ,这个导航定位系统在定位精度和数据处理速度上均可满足机器人导航的要求。

模糊Petri网自动生成方法研究

为解决模糊Petri网建模效率低、工作量大、易出错等问题,提出了模糊产生式规则自动生成模糊Petri网的方法,并给出了其映射模型。该方法通过模型映射,结合图元生成与定位实现了模糊Petri网的自动建模。避免了模糊Petri网建模的人为失误,提高了建模效率。使知识库与模型库同步更新,保证二者的一致性。有利于充分发挥模糊Petri网的知识表示、模糊信息处理与动态并行推理的优势,对模糊Petri网理论的广泛应用具有推动作用。通过实例表明该方法是可行的。

胜利勘探数据中心及勘探辅助决策系统研究

In the paper through extensive study and design, the technical plan for establishing the exploration database center is made to combine imported and self developed techniques. By research and repeated experiment a modern database center has been set up with its hardware and network having advanced performance, its system well configured, its data store and management complete, and its data support being fast and direct. Through study on the theory, method and model of decision an exploration decision assistant schema is designed with one decision plan of well location decision support system being evaluated and put into action. 1. Study on the establishment of Shengli exploration database center Research is made on the hardware configuration of the database center including its workstations and all connected hardware and system. The hardware of the database center is formed by connecting workstations, microcomputer workstations, disk arrays, and those equipments used for seismic processing and interpretation. Research on the data store and management includes the analysis of the contents to be managed, data flow, data standard, data QC, data backup and restore policy, optimization of database system. A reasonable data management regulation and workflow is made and the scientific exploration data management system is created. Data load is done by working out a schedule firstly and at last 200 more projects of seismic surveys has been loaded amount to 25TB. 2. Exploration work support system and its application Seismic data processing system support has the following features, automatic extraction of seismic attributes, GIS navigation, data order, extraction of any sized data cube, pseudo huge capacity disk array, standard output exchange format etc. The prestack data can be accessed by the processing system or data can be transferred to other processing system through standard exchange format. For supporting seismic interpretation system the following features exist such as auto scan and store of interpretation result, internal data quality control etc. the interpretation system is connected directly with database center to get real time support of seismic data, formation data and well data. Comprehensive geological study support is done through intranet with the ability to query or display data graphically on the navigation system under some geological constraints. Production management support system is mainly used to collect, analyze and display production data with its core technology on the controlled data collection and creation of multiple standard forms. 3. exploration decision support system design By classification of workflow and data flow of all the exploration stages and study on decision theory and method, target of each decision step, decision model and requirement, three concept models has been formed for the Shengli exploration decision support system including the exploration distribution support system, the well location support system and production management support system. the well location decision support system has passed evaluation and been put into action. 4. Technical advance Hardware and software match with high performance for the database center. By combining parallel computer system, database server, huge capacity ATL, disk array, network and firewall together to create the first exploration database center in China with reasonable configuration, high performance and able to manage the whole data sets of exploration. Huge exploration data management technology is formed where exploration data standards and management regulations are made to guarantee data quality, safety and security. Multifunction query and support system for comprehensive exploration information support. It includes support system for geological study, seismic processing and interpretation and production management. In the system a lot of new database and computer technology have been used to provide real time information support for exploration work. Finally is the design of Shengli exploration decision support system. 5. Application and benefit Data storage has reached the amount of 25TB with thousand of users in Shengli oil field to access data to improve work efficiency multiple times. The technology has also been applied by many other units of SINOPEC. Its application of providing data to a project named Exploration achievements and Evaluation of Favorable Targets in Hekou Area shortened the data preparation period from 30 days to 2 days, enriching data abundance 15 percent and getting information support from the database center perfectly. Its application to provide former processed result for a project named Pre-stack depth migration in Guxi fracture zone reduced the amount of repeated process and shortened work period of one month and improved processing precision and quality, saving capital investment of data processing of 30 million yuan. It application by providing project database automatically in project named Geological and seismic study of southern slope zone of Dongying Sag shortened data preparation time so that researchers have more time to do research, thus to improve interpretation precision and quality.