Promotional Effect of Bismuth as Dopant in Bi-Doped Vanadyl Pyrophosphate Catalysts for Selective Oxidation of n-Butane to Maleic Anhydride

Bismuth-promoted （1% and 3%） vanadyl pyrophosphate catalysts were prepared by refluxing Bi（NO3）4.5H2O and VOPO4.2H2O in isobutanol. The incorporation of Bi into the catalysts lattice increased the surface area and lowered the overall V oxidation state. Profiles of temperature programmed reduction （TPR） in H2 show a significant shift of the maxima of major reduction peaks to lower temperatures for the Bi-promoted catalysts. A new peak was also observed at the low temperature region for the catalyst with 3% of Bi dopant. The addition of Bi also increased the total amount of oxygen removed from the catalysts. The reduction pattern and reactivity information provide fundamental insight into the catalytic properties of the catalysts. Bi-promoted catalysts were found to be highly active （71% and 81% conversion for 1% and 3% Bi promoted catalysts, respectively, at 703 K）, as compared to the unpromoted material （47% conversion）. The higher activity of the Bi-promoted catalysts is due to that these catalysts possess highly active and labile lattice oxygen. The better catalytic performance can also be attributed to the larger surface area.

Distribution pattern and conservation of threatened medicinal and aromatic plants of Central Himalaya, India

A study was conducted to examine the distribution pattern of four rhizomatous medicinal and aromatic plant species （MAPs） viz., Angelica glauca, Pleurospermum angelicoides, Rheum emodi and Arne- bia benthamii in different forest stands in Central Himalaya. Results show that A. glauca and P. angelicoides had a higher （50%） frequency at Chipkoan, Garpak and Phagati forest, R. emodi had a higher （60%） frequency at Rishikund, Suki and Himtoli, and A. benthamii had a higher （70%） frequency at Suki and Khambdhar The densities of A. glauca （0.6 plants·m -2 ） and P. angelicoides （0.5 plants·m -2 ） were higher at Chipkoan and Garpak sites than at other micro-sites, while densities of R. emodi （0.8 plants·m -2 ） and A. benthamii （1.0 plants·m -2 ） were higher at Suki and Khambdhar sites. A. glauca had highest total basal covers （TBC） （1.2 cm 2 ·m -2 ） at Chipkoan, P. angelicoides had highest TBC （0.92 cm 2 ·m -2） at Lati kharak site, A. benthamii had the highest TBC （6.48 cm 2 ·m -2 ） atKhambdhar, and R. emodi had highest TBC （4.53 cm 2 ·m -2 ） at Rishikund. For the four studied species, A. glauca showed a contagious distribution, P. angelicoides and R. emodi showed the random and A. benthamii showed the regular type of distribution.

Maintenance of an abrupt boundary between needle-leaved and broad-leaved forests in a wetland near coast

There is an abrupt boundary between two well-developed wetland forests, a stand consisting of a broad-leaved, nitrogen-fixer Alnusjaponica and a stand of the needle-leaved Picea glehnii Masters, in eastern Hokkaido, Japan. To clarify maintenance mechanisms, we studied the forest profile, water level, groundwater and precipitation chemistry, seedling establishment patterns in relation to microhabitats, and seed migration. The profile of groundwater level insufficiently explained the abrupt boundary formation, while the groundwater chemistry differed significantly between the two forests ; i.e., EC, Na^＋, K^＋, Mg^2＋, Ca^2＋ and Cl^- were higher in P. glehnii forest and pH was lower. Precipitation in P. glehnii forest contained richer Na＋, Ca^2＋ and Cl^-, indicating that the differences in surface-water chemistry were mostly derived from precipitation. Solar radiation was less than 2.2 MJ.m^-2.d^-1 on P. glehnii forest in late June, while that was patchily distributed in A.japonica forest with a range from 1.0 to 3.7 MJ＇m^-2＇d^-1. Moss cover on the soil surface, most of which were made of Sphagnum spp., was 60% in P. glehnii forest, but was 10% in A. japonica forest. Surface water chemistry represented by pH was considered to determine the development of Sphagnum moss. About 70% of P. glehnii seedlings 〈 1.3 m in height established on moss cover. Seed-sowing experiments suggested that seed germination and seedling survival for both species were significantly higher in P. glehnii forest. Therefore, the regeneration of P. glehnii in A. japonica forest was negligible, owing to the paucity of favorable microhabitats and low seedling establishment. A. japonica regenerated only by resprouting, and the seedlings were few in both forests. In addition, A. japonica seed migration into the P. glehnii forests was greatly restricted, and low solar radiation in the P. glehnii forest contributed to low seedling survival. Based on those results, we concluded that Picea glehnii and Alnusjaponica could develop distinct and selfish environments being unsuitable for the other species and inhibit natural afforestation of another species each other by excluding invasion.

Maintenance of an abrupt boundary between needle-leaved and broad-leaved forests in a wetland near coast

There is an abrupt boundary between two well-developed wetland forests, a stand consisting of a broad-leaved, nitrogen-fixer Alnus japonica and a stand of the needle-leaved Picea glehnii Masters, in eastern Hokkaido, Japan.To clarify maintenance mechanisms, we studied the forest profile, water level, groundwater and precipitation chemistry, seedling establishment patterns in relation to microhabitats, and seed migration.The profile of groundwater level insufficiently explained the abrupt boundary formation, while the groundwater che-mistry differed significantly between the two forests;i.e., EC, Na+, K+, Mg2+, Ca2+ and Cl-were higher in P.glehnii forest and pH was lower.Precipitation in P.glehnii forest contained richer Na+, Ca2+ and Cl-, indicating that the differences in surface-water chemistry were mostly derived from precipitation.Solar radiation was less than 2.2 MJ·m-2·d-1 on P.glehnii forest in late June, while that was patchily distributed in A.japonica forest with a range from 1.0 to 3.7 MJ·m-2·d-1.Moss cover on the soil surface, most of which were made of Sphagnum spp., was 60% in P.glehnii forest, but was 10% in A.japonica forest.Surface water chemistry represented by pH was considered to determine the development of Sphagnum moss.About 70% of P.glehnii seedlings < 1.3 m in height established on moss cover.Seed-sowing experiments suggested that seed germination and seedling survival for both species were significantly higher in P.glehnii forest.Therefore, the regeneration of P.glehnii in A.japonica forest was negligible, owing to the paucity of favorable microhabitats and low seedling establishment.A.japonica regenerated only by resprouting, and the seedlings were few in both forests.In addition, A.japonica seed migration into the P.glehnii forests was greatly restricted, and low solar radiation in the P.glehnii forest contributed to low seedling survival.Based on those results, we concluded that Picea glehnii and Alnus japonica could develop distinct and selfish environments being unsuitable for the other species and inhibit natural afforestation of another species each other by excluding invasion.

Biomass production of herb species in broad leaf forests in Kumaun Himalaya,India

The study focuses on the dynamics and biomass production （g·m-2） of understory （herbaceous） plant community under broad-leaf forests consisting of Quercus leucotrichophora （Banj-oak）, Quercus floribunda （Tilonj-oak） and Quercus semicarpifolia （Kharsu-oak）, respectively in central Himalaya, India. With increasing altitudes, the den-sity and biomass decreased significantly across the three types of forests. Banj-oak forest harboured the maximum density and biomass among the other sampling sites. The mean density of herb species in two contrasting orientation differed significantly （p0.05）, showing relatively higher density on slope orientation （west）. Across the sites, total production declined significantly with increasing altitude of the sites （p0.05）, and Banj-oak forest presented the highest production.

Toward development of the 4Dvar data assimilation system in the Bering Sea:reconstruction of the mean dynamic ocean topography

The Bering Sea circulation is derived as a variational inverse of hydrographic profiles（ temperature and salinity） , atmospheric climatologies and historical observation of ocean curents. The important result of this study is estimate of the mean climatological sea surface height （SSH） that can be used as a reference for satellite altimetry sea level anomaly data in the Bering Sea region. Numerical experiments reveal that, when combined with satellite altimetry, the obtained reference SSH effectively constrains a realistic reconstruction of the Amukta Pass circulation.

青藏高原那曲河流域降水及河流水体中氧稳定同位素研究

根据青藏高原中部那曲河流域 1 998年夏季测得的上下游中稳定同位素的日变化 ,并与同期观测的流域降水中稳定同位素比较 ,分析了河水中δ18O的变化特征 ,初步研究了该流域的稳定同位素水文循环过程。河水中δ18O的变化幅度远小于降水 ,它是降水中δ18O、降水量以及地表蒸发过程共同作用的结果。研究发现湖水对于稳定同位素变化起着显著的调节作用。

青藏高原中部水蒸发过程中的氧稳定同位素变化

作为青藏高原稳定同位素水文循环的一个重部分 ,1 998年夏首次在青藏高原中部的那曲和安多两地同时进行了水蒸发过程中氧稳定同位素变化观测研究 .模拟和实验结果都显示出了大气相对湿度对水蒸发过程中氧稳定同位素变化的显著影响 .模拟结果还显示剩余水中δ18O与剩余水比率呈指数关系 ,但实验分析结果表明 ,蒸发过程中剩余水中δ18O与剩余水比率更接近于线性关系 ,这种关系可以定量地表示出来 .从理论上与实验中都可以计算出不同相对湿度下蒸发分馏因子的大小 .并且实验结果与理论模拟结果较一致 .

青藏高原中部降水稳定同位素变化与季风活动

根据1998年夏季中日GAME/Tibet项目在青藏高原中部进行的降水中稳定同位素研究结果以及相关的气象观测资料,分析了青藏高原中部夏季降水中δ18O的变化规律。研究结果发现,青藏高原中部夏季降水中δ18O的波动与大规模天气活动有关,而不是地方性的气象条件。该地区降水中δ18O对水汽来源的变化以及水汽的输送过程十分敏感。夏季伴随西南季风进入高原南部的水汽形成的降水中δ18O较低,而且季风活动越强,降水中δ18O也越低。从青藏高原北部而来的水汽或地方蒸发水汽形成的降水,其δ18O值较高。

亲水单分散聚合物基质阳离子色谱柱的制备及其应用

以自制5.0μm单分散大孔亲水交联聚甲基丙烯酸环氧丙酯微球为基质,合成一种新型弱酸性阳离子色谱填料。选用甲烷磺酸作淋洗液,在流速为1.0mL/min时,对6种无机阳离子(Li+,Na+,NH4+,K+,Mg2+,Ca2+)和有机胺进行了良好分离。考察了淋洗液种类、浓度以及流速对6种无机阳离子分离的影响,选择了合适的色谱分离条件。测得6种离子在一定浓度范围内具有良好的线性关系和低的检出限。将其用于决明茶中阳离子的分析,4种离子在20min内完全分离,各离子标准加入回收率在96%～107%之间。此色谱柱的分离效果与DionexIonPac(CS12A商品柱接近,但分析时间缩短了44min。

单分散亲水两性离子交换树脂的制备及其在生物大分子分离中的应用

采用分散聚合与溶胀聚合相结合的方法及高分子溶液致孔技术,成功地制备了粒径为5.0μm大孔和超大孔结构的单分散亲水性交联聚甲基丙烯酸环氧丙酯树脂,并进行了结构表征.将该树脂经胺化后再与1,3-丙磺酸内酯反应,得到一种新型的两性离子交换(强阳-强阴型)高效液相色谱填料.研究了该填料对标准蛋白分离性能及流动相中有机溶剂、流速和pH值对蛋白保留的影响.实验结果表明,在流速为3mL/min时,采用线性梯度洗脱,在4.0min内可同时快速基线分离3种酸性和2种碱性蛋白.

多孔单分散交联聚苯乙烯-二乙烯苯离子对色谱固定相分离8种阴离子

以一步种子溶胀聚合法制备的粒径为8μm的多孔单分散交联聚苯乙烯-二乙烯苯(PSt-DVB)树脂为离子对色谱固定相,2mmol/L氢氧化四丁基铵(TBAOH)、10%(V/V)乙腈和1.5mmol/LNa2CO3的混合液为流动相,在流速为1.0mL/min下,成功实现了8种阴离子(F-,Ac-,Cl-,NO2-,Br-,NO3-,SO42-和HPO24-)的分离。考察了淋洗液的配比对8种无机阴离子分离的影响。在最优条件下,8种离子表现出良好的重现性及较好的线性关系,色谱柱具有良好稳定性及较好的分离能力。将其用于雪水中阴离子的分析,6种离子在15min内完全分离,各离子加标回收率在93.6%～110.4%之间。此固定相也可用于IO3-,HCOO-,ClO3-,BrO3-,ClCH2COO-和H2C2O4混合样的分离。

A spectral response approach for detecting dominant phytoplankton size class from satellite remote sensing

An important goal in ocean colour remote sensing is to accurately detect different phytoplankton groups with the potential uses including the validation of multi-phytoplankton carbon cycle models; synoptically monitoring the health of our oceans, and improving our understanding of the bio-geochemical interactions between phytoplankton and their environment. In this paper a new algorithm is developed for detecting three dominant phytoplankton size classes based on distinct differences in their optical signatures. The technique is validated against an independent coupled satellite reflectance and in situ pigment dataset and run on the 10-year NASA Sea viewing Wide Field of view Sensor （SeaWiFS） data series. Results indicate that on average 3.6% of the global oceanic surface layer is dominated by microplankton, 18.0% by nanoplankton and 78.4% by pieoplankton. Results, however, are seen to vary depending on season and ocean basin.

Decadal Variability Shown by the Arctic Ocean Hydrochemical Data and Reproduced by an Ice-Ocean Model

The Arctic is experiencing a significant warming trend as well as a decadal oscillation. The atmospheric circulation represented by the Polar Vortex and the sea ice cover show decadal variabilities, while it has been difficult to reveal the decadal oscillation from the ocean interior. The recent distribution of Russian hydrochemical data collected from the Arctic Basin provides useful information on ocean interior variabilities. Silicate is used to provide the most valuable data for showing the boundary between the silicate-rich Pacific Water and the opposite Atlantic Water. Here, it is assumed that the silicate distribution receives minor influence from seasonal biological productivity and Siberian Rivers outflow. It shows a clear maximum around 100m depth in the Canada Basin, along with a vertical gradient below 100 m, which provides information on the vertical motion of the upper boundary of the Atlantic Water at a decadal time scale. The boundary shifts upward (downward), as realized by the silicate reduction (increase) at a fixed depth, responding to a more intense (weaker) Polar Vortex or a positive (negative) phase of the Arctic Oscillation. A coupled ice-ocean model is employed to reconstruct this decadal oscillation.

A three-dimensional ocean general circulation model for mesoscale eddies——Ⅱ Diagnostic analysis

A three-dimensional density field associated with mesoscaie unstable waves generated by the 3-D, primitive-equation model (Wang and Ikeda, 1996) is provided to the quasi-geostrophic pressure tendency and ω-equations, and to the (ageostrophic) Q-vector equation. Diagnostic analyses, analogous to the approaches in meteorology: ω-equation and Q-vector method, are for the first time developed to examine the mesoscaie dynamical processes and mechanisms of the unstable waves propagating in the mid-latitude ocean. The weaknesses and strengths of these two diagnostic approaches are evaluated and compared to the model results. The Q-vector method is then recommended to diagnose the vertical motion associated with the mesoscaie dynamics from a hydrographic CTD (conductivity-temperature-depth) array, while the quasi-geostrophic equations produce some small-scale features (errors) in the diagnosed fields.

A 60 000-year loess-paleosol record of millennial-scale summer monsoon instability from Lanzhou, China

The 28-m high-resolution Shajinping loess section in Lanzhou on the Chinese western Loess Plateau records a detailed history of millennial Asian summer monsoon change since the earlier last glaciation. Summer monsoon proxies of soil magnetic susceptibility, carbonate content and soil color show that Asian summer monsoon experienced a series of rapid

A short note on seed dispersal by colobines:the case of the proboscis monkey

Although the role of primates in seed dispersal is generally well recognized,this is not the case for colobines,which are widely distributed in Asian and African tropical forests.Colobines consume leaves,seeds and fruits,usually unripe.A group of proboscis monkeys(Colobinae,Nasalis larvatus)consisting of 1 alpha-male,6 adult females and several immatures,was observed from May 2005 to May 2006.A total of 400 fecal samples from focal group members covering 13 months were examined,with over 3500 h of focal observation data on the group members in a forest along the Menanggul River,Sabah,Malaysia.Intact small seeds were only found in 23 of 71 samples in Nov 2005,15 of 38 in Dec 2005 and 5 of 21 in Mar 2006.Seeds of Ficus(all<1.5 mm in length)were found in all 3 months and seeds from Antidesma thwaitesianum(all<3 mm)and Nauclea subdita(all<2 mm)only in Nov and Dec,which was consistent with members of the study group consuming fruits of these species mostly at these times.To our knowledge,these are the fi rst records of seeds in the fecal samples of colobines.Even if colobines pass relatively few seeds intact,their high abundance and biomass could make them quantitatively significant in seed dispersal.The potential role of colobines as seed dispersers should be considered by colobine researchers.

Role of Salix reinii patches in spatio-temporal patterns of cohabitants on a Japanese volcano

Shrub patches often support the colonizers particularly under stressful and/or disturbed environments.The intensities of stresses and disturbances on mountains are often related to an elevation gradient and are decreased by shrub patches(canopy and litter).We aim to clarify these relationships by using shrub patches at different elevations on a volcano.We monitored all shoots in plots established inside and outside of patches of Salix reinii(Salicaceae)and their related environments,such as temperature,light,moisture and chemistry,at three elevations on Mount Koma(1131 m a.s.l.),northern Japan,from early spring in 2005 to summer in 2006.The patch structures were evaluated by area,branch density and litter thickness.The structures of shrub patches did not differ among the elevations.The patches increased the diversity of rare species,by an overall increase in plant species richness.The moisture,nitrogen and phosphate contents in the patches were higher than outside of patches.The effects of shrub patches on the cohabitants were overall positive,although the effects were negative on seedling abundance,shoot survival and flowering.These results suggest that the growth patterns of shrub patches determine the plant community structures and facilitate plant diversity.

青藏高原南部季风降水中稳定同位素波动与水汽输送过程

利用NCEP气象数据建立模型来追踪青藏高原南部降水的水汽输送过程,并与实测降水中氧稳定同位素数据进行对比分析,讨论了青藏高原南部降水中δ^(18)O波动与水汽输送过程的关系.研究发现降水中极低的δ^(18)O都与低层洋面蒸发水汽输送有关,远距离水汽输送时,水汽输送过程中的降水使得稳定同位素的贫化作用加强,结果实测降水中δ^(18)O很低;降水中低的δ^(18)O值往往伴随着厚层水汽输送,而且高层大气水汽的凝结作用强烈,这一过程也加剧了稳定同位素的贫化,使得实测降水中δ^(18)O很低.而降水中高的δ^(18)O值无论是在季风降雨期的前后还是在季风活动阶段,水汽输送都与高原面上蒸发的水汽有关,而缺乏低海拔洋面蒸发的水汽输送,并且水汽主要来源于北方或西方.模型计算结果与稳定同位素的分馏机理相一致.

Contrasting magnetic properties from two loess/paleosol sections in Gansu Province, west China

We made comparison of magnetic property between two loess/paleosol sediments from theBeiyuan section, Linxia and the Shajinping section, Lanzhou. The two sections apart only 100 km inNE-SW direction. At the Beiyuan section, enhancement of the low-field magnetic susceptibility, ARMsusceptibility and SIRM are observed in paleosols. The positive correlations among these threeparameters suggest the presence of two magnetic components, i.e. the background component and theenhanced component. The unblocking curves of low-temperature IRM give strong evidence for the ideaof the two components. On the contrary, the magnetic parameters are almost constant throughout theShajinping section. The enhanced component is not found in the Shajinping section. The magneticproperties of the background component are indistinguishable between the two sections. Contrastingmagnetic properties imply the difference of soil formation process between the two sections.