Developments and applications of supported liquid phase catalysts

Supported liquid phase catalyst (SLPC) is one of effectively heterogenized homogeneous catalysts using organometallic complexes as active components, which are dissolved in a small quantity of liquid phase dispersed in the form of isle or film on the surface of supports. The SLPC has successfully been applied for several chemical transformations and this article will review recent results with respect to the preparation and catalytic performance, the applicability to continuous flow operations, and the capability of multifunctional catalysis.

Syntheses, structures and near-IR luminescent studies on ternary lanthanide (Er-III, Ho-III, Yb-III, Nd-III) complexes containing 4,4,5,5,6,6,6-heptafluoro-1-(2-thienyl)hexane-1,3-dionate

The ligand Hhfth [4,4,5,5,6,6,6-heptafluoro-1-(2-thienyl)hexane-1,3-dione], which contains a heptafluoropropyl group, has been used to synthesize several new ternary lanthanide complexes (Ln = Er, Ho, Yb, Nd) in which the synergistic ligand is 1,10-phenanthroline (phen) or 2,2'-bipyridine (bipy). The two series of complexes are [Ln(hfth)(3)phen] [abbreviated as (Ln)1, where Ln = Er, Ho, Yb] and [Ln(hfth)(3)bipy] [abbreviated as (Ln)2, where Ln = Er, Ho, Yb, Nd]. Members of the two series have been structurally characterized. The growth morphology, diffuse reflectance (DR) spectra, thermogravimetric analyses, and photophysical studies of these complexes are described in detail. After ligand-mediated excitation of the complexes, they all show the characteristic near-infrared (NIR) luminescence of the corresponding Ln(3+) ions (Ln = Er, Ho, Yb, Nd). This is attributed to efficient energy transfer from the ligands to the central Ln(3+) ions, i.e. an antenna effect. The heptafluorinated substituent in the main hfth sensitizer serves to reduce the degree of vibrational quenching. With these NIR-luminescent lanthanide complexes, the luminescent spectral region from 1300 to 1600 nm, which is of particular interest for telecommunication applications, can be covered completely.

Sintering of nanopowders of amorphous silicon nitride under ultrahigh pressure

Nanopowders of amorphous silicon nitride were densified and sintered without additives under ultrahigh pressure (1.0-5.0 GPa) between room temperature and 1600 degrees C. The powders had a mean diameter of 18 nm and contained similar to 5.0 wt% oxygen that came from air-exposure oxidation, Sintering results at different temperatures were characterized in terms of sintering density, hardness, phase structure, and grain size. It was observed that the nanopowders can be pressed to a high density (87%) even at room temperature under the high pressure. Bulk Si3N4 amorphous and crystalline ceramics (relative density: 95-98%) were obtained at temperatures slightly below the onset of crystallization (1000-1100 degrees C and above 1420 degrees C, respectively. Rapid grain growth occurred during the crystallization leading to a grain size (>160 nm) almost 1 order of magnitude greater than the starting particulate diameters, With the rise of sintering temperature, a final density was reached between 1350 and 1420 degrees C, which seemed to be independent of the pressure applied (1.0-5.0 GPa), The densification temperature observed under the high pressure is lower by 580 degrees C than that by hot isostatic pressing sintering, suggesting a significantly enhanced low-temperature sintering of the nanopowders under a high external pressure.

Sol-gel synthesis and luminescence of Y4Al2O9:RE3+(RE=Eu, Tb)

Y4Al2O9 (YAM) was prepared by a sol-gel process, using yttrium and aluminum citrate complexes as precursors. The sol-gel process produced single-phase YAM at 900 degrees C, as opposed to the conventional solid-state reaction, which led to the formation of other phases, even if at 1600 degrees C. The emission and excitation spectra of Eu3+ and Tb3+ in YAM showed the existence of two luminescence centers, agreeing with the crystal structure of YAM. The spectral properties of the samples are discussed.

平台石墨炉原子吸收光谱法直接测定人眼视网膜下液中微量铬、锰

本文采用平台和硝酸镁硝酸钯混合基体改进剂相结合的方法,使铬和锰的灰化温度从1200℃提高至1600℃,克服了大量钾、钠、钙、镁等共存元素的干扰,可直接测定样品中微量铬和锰。对于铬和锰的检出限分别为5.6×10~(-11)g和9×10~(-11)g,相对标准偏差分别为8.7％和7.5％,测定结果与等离子体发射光谱法结果一致。

A potent anti-oxidant property: fluorescent recombinant alpha-phycocyanin of Spirulina

To express and product a fluorescent antioxidant holo-alpha-phycocyanin (PC) of Spirulina platensis (Sp) with His-tag (rHHPC; recombinant holo-alpha-phycocyaninof Spirulina platensis with His-tag) in 5-l bench scale. A vector harbouring two cassettes was constructed: cpcA along with cpcE-cpcF in one cassette; ho1-pcyA in the other cassette. Lyases CpcE/F of Synechocystis sp. PCC6803 (S6) could catalyse the 82 site Cys in apo-alpha-PC of Sp linking with bilin chromophores, and rHHPC was biosynthesized in Escherichia coli BL21. The constant feeding mode was adopted, and transformant reached the biomass of rHHPC up to 0.55 g l(-1) broth in 5-litre bench scale. rHHPC was purified by Ni2+ affinity column conveniently. The absorbance and the fluorescence emission spectra of rHHPC had lambda(max) at 621 and 650 nm, respectively. The IC50 values of rHHPC were 277.5 +/- 25.8 mu g ml(-1) against hydroxyl radicals and 20.8 +/- 2.2 mu g ml(-1) against peroxyl radicals. Combinational biosynthesis of rHHPC was feasible, and the constant feeding mode was adopted to produce good yields of rHHPC. Fluorescent rHHPC with several unique qualitative and quantitative features was effective on scavenging hydroxyl and peroxyl radicals. A potent antioxidant rHHPC was co-expressed, produced and characterized for nutritional and pharmacological values, which would help to develop phycobiliproteins' applications in their fluorescent and biological activities.

Tank cultivation of the red alga Palmaria palmata: Effects of intermittent light on growth rate, yield and growth kinetics

Tank cultivation of marine macroalgae involves air-agitation of the algal biomass and intermittent light conditions, i.e. periodic, short light exposure of the thalli in the range of 10 s at the water surface followed by plunging to low light or darkness at the tank bottom and recirculation back to the surface in the range of 1-2 min. Open questions relate to effects of surface irradiance on growth rate and yield in such tumble cultures and the possibility of chronic photoinhibition in full sunlight. A specially constructed shallow-depth tank combined with a dark tank allowed fast circulation times of approximately 5 s, at a density of 4.2 kg fresh weight (FW) m(-2) s(-1). Growth rate and yield of the red alga Palmaria palmata increased over a wide range of irradiances, with no signs of chronic photoinhibition, up to a growth-saturating irradiance of approximately 1600 mumol m(-2) s(-1) in yellowish light supplied by a sodium high pressure lamp at 16 h light per day. Maximum growth rate ranged at 12% FW d(-1), and maximum yield at 609 g FW m(-2) d(-1). This shows that high growth rates of individual thalli may be reached in a dense tumble culture, if high surface irradiances and short circulation times are supplied. Another aspect of intermittent light relates to possible changes of basic growth kinetics, as compared to continuous light. For this purpose on-line measurements of growth rate were performed with a daily light reduction by 50% in light-dark cycles of 1, 2 or 3 min duration during the daily light period. Growth rates at 10degreesC and 50 mumol photon m(-2) s- 1 dropped in all three intermittent light regimes during both the main light and dark periods and reached with all three periodicities approximately 50% of the control, with no apparent changes in basic growth kinetics, as compared to continuous light.

Relationship between differential retention of Escherichia coli and Enterococcus faecalis and variations in enzyme activity in the scallop Patinopecten yessoensis

Uptake of Escherichia coli and Enterococcus faecalis and variations of trypsin amylase activity acid phosphatase and superoxide dismutase in tissue of the scallop Patinopecten yessoensis were detected. The results showed that P. yessoensis accumulated E. faecalis in larger numbers and more rapidly than E. coli, both with the highest concentration in the digestive tract and lowest in hemolymph. Compared to E. coil, all scallops exposed to E. faecalis showed significantly higher trypsin and AMS activity. SOD activity in hemocytes and ACP activity in hemolymph was significantly higher in the treatments with 5 log(10)CFU/ml E. colt than with E. faecalis. But no significant differences in ACP activity of P. yessoensis exposed to a 3 log(10)CFU/ml inoculum of both bacteria were recorded. In conclusion, the mass retention of gut microflora in P. yessoensis is positively correlated with digestive enzymes activity and negatively correlated with ACP activity in the hemocyte. (C) 2010 Published by Elsevier Ltd.

中国及相关海域褐虾总科系统分类学和动物地理学研究

褐虾总科包括褐虾科和镰虾科，是重要的底栖生物类群，而且很多褐虾种为常见的经济种，其中中国北方海域最常见的为日本褐虾Crangon hakodatei Rathbun, 1902，另外黄海褐虾Crangon uritai Kim & Hayashi, 1999在黄渤海也较为常见。在东海和南海，污泥疣褐虾Pontocaris pennata (Bate, 1888)和拉氏爱琴虾Aegaeon lacazei (Gourret, 1887)在底栖生物拖网时常可采到，有很大的经济价值。我国对褐虾总科的研究很少，亟需对我国海域的褐虾进行全面的系统分类学和地理分布研究。 本论文所依据的标本主要为中国科学院海洋研究所海洋生物标本馆馆藏的约1600号褐虾类标本，标本主要采自渤海、黄海、东海、南海四大海域，也有部分标本采自日本海、南极和北极等海域，并得到国外同行专家惠赠的褐虾类标本约100号，同时也检查了其它单位保藏的少量标本。 本论文主要采用传统的形态学方法进行分类学研究，共鉴定出褐虾科14属25种，其中1个新种，6个新记录种，镰虾科1属7种，其中2个新种，3个新记录种。参照历史文献与现在研究结果，中国海域的褐虾类至少有2科11属44种。 本文通过对约1700号标本的详细检查，总结了各个属和种的分类学特征和地理分布特点，对各属的分种均附有详细系统的检索表，对鉴定的32种褐虾均附有详细的背面整体图和侧面整体图以及附肢等的局部形态图，并对各种进行了中文名称的考订。 本研究是我国首次关于褐虾总科的系统分类学和动物地理学研究，研究结果将改变我国在褐虾总科研究报道方面的薄弱现状，并为此动物类群的多样性等研究提供重要的基础资料。研究结果澄清了分类学上存在争议的疑难种，发现了3个新种，报道了9个新记录种，阐明了我国褐虾总科的区系特点。

东营凹陷辛东地区层序地层格架与油气藏预测研究

本文以东营凹陷辛东地区古近纪及新近纪地层为研究目标，通过层序地层划分、沉积相分析、储层评价和油藏特征及成藏模式研究，综合评价了油气藏，并进行了有利勘探目标预测。 在辛东地区首次通过层序地层学原理划分4个二级层序、7个三级层序，为储层和圈闭预测建立的等时层序地层格架；岩石类型主要包括砂岩、灰岩、泥岩和页岩等，以砂岩和泥岩为主。通过岩心观察、测井曲线分析、单井沉积相研究，结合剖面地震相和剖面沉积相分析表明，研究区发育三角洲、滨浅湖、半深湖-深湖相、湖底扇等沉积类型，形成浊积扇体-前三角洲-三角洲前缘-三角洲平原-河流相-浅湖亚相纵向演化序列，包括了含砾砂岩、中粗砂岩、细砂岩及粉砂岩储层；储层以次生孔隙为主，存在1600 ~ 2200m和2600 ~ 3200m次生孔隙带，为碳酸盐胶结物和长石与部分岩屑的溶蚀作用和粘土矿物脱水作用所致，在断裂活动、有效烃源岩成熟度范围的中细砂岩内最发育；较好的渗透层主要分布在东营组、沙二段和沙三上亚段。 研究区发育断层、岩性、断层-岩性等类型油气藏，主要形成于① 古近纪末东营期的生油层系内及邻近地区，以原生岩性油气藏为主；② 新近纪至第四纪沉积时期，其中新近纪明化镇和第四纪沉积时期，成为油气运聚的重要时期。成藏动力学系统呈现下部自源原生封闭型、中部它源原生半封闭型及上部它源次生开放型三种典型特征。 通过对成藏主控因素和油气分布规律的综合认识，在本区优选出3个有利勘探区域：① 沙三中下及沙四段浊积砂体，在构造翼部地区发育岩性油藏；② 沙二段和沙三上砂体，孔渗条件好，断层封堵性控制油藏；③ 馆陶-明化镇组浅层次生油藏，油气沿着断层、砂体不断地从翼部的深层向核部的浅层运聚形成油藏。

青藏高原主要植被类型生物生产量的比较研究

以18种群落类型的实测数据和1013块森林测树样地的估算数据为基础，首次系统地分析和比较了青藏高原主要植被类型生物生产量的构成规律及分布格局。亚高山暗针叶林的生物量一般在300t/hm2以上，最高可达约1600 t/hm2，叶生物量8～39 t/hm2，根茎比0.1～0.2，生产量8～13 t/hm2．a-；高山灌丛类型生物量20～40t/hm2，叶生物量3～6t/hm2，根茎比0.4～0.8，生产量4～7 t/hm2．a-；高寒草甸生物量一般为20～60 t/hm2，沼泽草甸高达100 t/hm2以上，叶生物量2.5～5.5 t/hm2，根茎比8～20，生产量4～9 t/hm2．a-；高原冬小麦和春小麦年生物产量高达26～30 t/hm2，叶生物量12～16t/hm2，根茎比约0.06。在垂直分异方面，随着海拔升高，生物量呈递增, 在一定海拔高度达最大, 海拔继续升高生物量则迅速下降;而生产量随海拔升高一般呈递减趋势, 反映出热量条件随海拔升高而递减的限制作用。与全国相比, 青藏高原同一森林植被类型的生物量均高于全国的平均水平, 而其生产量基本持平。

智能机器人系统分层递阶智能控制结构的分析与综合

智能机器人是分层递阶智能控制结构开放的复杂巨系统。本文根据神经科学、人脑智能的三个重要特性,对智能机器人系统分屋递阶智能控制结构、功能和各个层级的基本理论做了简要的论述和分析,采用从定性到定量的综合集成技术,用概率模型表达组织级的推理、规划、决策的不确定性,分配协调级的任务,和执行级的控制作用,用熵作为系统分层递阶各级性能的集成测度,建立智能控制的数学模型。智能机器人系统综合可以以下述数学问题为出发点,即寻求适当的决策与控制序列,随智能递降而精度递增的原则,构成系统的总体熵最小,即可获得最优决策、最优控制和最优设计;用在核电站中自动检修的移动式智能机器人系统求熵最小值改善系统性能有效性的事例做了简要说明,进而提出实现的基本途径和应用前景。

中国北方中新世风尘物质来源及古气候的地球化学指示

The most prominent tectonic and environmental events during the Cenozoic in Asia are the uplift of the Himalaya-Tibetan plateau, aridification in the Asian interior, and onset of the Asian monsoons. These caused more humid conditions in southeastern China and the formation of inland deserts in northwestern China. The 22 Ma eolian deposits in northern China provide an excellent terrestrial record relative to the above environmental events. Up to date, many studies have focused on the geochemical characters of the late Mio-Pleistocene eolian deposits, however, the geochemical characteristics of the Miocene loess and soils is still much less known. In this study, the elemental and Sr-Nd isotopic compositions of the eolian deposits from the Qinan (from 22.0 to 6.2 Ma) and the Xifeng (from 3.5 Ma until now) loess-soil sections were analyzed to examine the grain size effects on the element concentrations and the implications about the dust origin and climate. The main results are as follows: 1. The contents of Si, Na, Zr and Sr are higher in the coarser fractions while Ti and Nb have the highest contents in the 2-8 μm fractions. Al, Fe, Mg, K, Mn, Rb, Cu, Ga, Zn, V, Cr, Ni, LOI have clear relationships with grain-size, more abundant in the fine fraction while non significant relationship is observed for Y. Based on these features, we suggest that K2O/Al2O3 ratio can be used to address the dust provenance, and that VR (Vogt ratio = (Al2O3+K2O)/(MgO+CaO+Na2O)) can be used as a chemical weathering proxy for the Miocene eolian deposits because of their relative independence on the grain size. Meanwhile, SiO2/Al2O3 molar ratio is a best geochemical indicator of original eolian grain size, as suggested in earlier studies. 2. Analyses on the Sr and Nd isotope composition of the last glacial loess samples (L1) and comparison with the data from the deserts in northern China suggest that that Taklimakan desert is unlikely to be the main source region of the eolian dust. In contrast, these data suggest greater contributions of the Tengger, Badain Jaran and Qaidam deserts to the eolian dust during the last glacial cycle. Since the geochemical compositions (major, trace, REE and Sr, Nd isotope) of loess samples for the past 22 Ma are broadly similar with the samples from L1, these data trend to suggest relatively stable and insignificant changes of dust sources over the past 22 Ma. 3. Chemical weathering is stronger for Miocene paleosol samples than for the Plio-Pleistocene ones, showing warmer/more humid climatic conditions with a stronger summer monsoon in the Miocene. However, chemical weathering is typical of Ca-Na removal stage, suggesting a climate range from semiarid to subhumid conditions. These support the notion about the formation of a semi-arid to semi-humid monsoonal regime by the early Miocene, as is consistent with earlier studies.

东北四海龙湾玛珥湖啊1500年来长链烯酮不饱和度温标与古水温重建

The alkenone unsaturation paleothermometer is an important proxy to reconstruct water temperature, and is widely applied to reconstructing sea surface temperature in most oceanographic settings. Recent research indicates that long chain alkenone is preserved in lacustrine sediments, and the alkenone unsaturation has good relationship with mean annual temperature in studied lakes. Thus, the alkenone unsaturation could be used as a temperature proxy to reconstruct temperature in limnic systems. In this study, we analyzed long chain alkenone from the varved sediments in Lake Sihailongwan, northeastern China. Based on the counting varves, we established time scale during the past 1500 years. The distribution pattern in the sediment is similar with the previous study in lacustrine environment. The ratio of C37:4 methyl ketone to the sum of C37 alkenones is high. Based on the published temperature- alkenone unsaturation equation, we reconstructed the mean air temperature and July water temperature during the past 1500 years. Three major cold periods are in AD560-950, AD 1540-1600 and AD1800-1920. Three major warm periods are AD450-550, AD 950-1400 and AD 1600-1800. The Medieval Warm Period was a significant warm periods. However, the traditional “Little Ice Age” was not a persistent cold period, and interrupted by relative longer warm period. The temperature variations in this study show a general similar pattern with the summer temperature reconstruction from Shihua Cave and the winter temperature from historical documents. The temperature variations from long chain alknone record show a good agreement with solar activity (10Be data from ice core and sunspot number from tree rings). It may suggest that solar activity is most important forcing in the studied area.