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Objective To investigate the combined effects of chronic obstructive pulmonary disease (COPD) and depression on spatial memory in old rats, aiming to better understand the comorbidity of the two diseases in geriatric patients. Methods The SD rats were assigned into five groups: adult control group (n=6), elderly control group (n=6), elderly COPD group (n=6), elderly depression group (n=6) and elderly COPD with depression group (n=6). Smoking and chronic unpredictable mild stress (CUMS) with solitary support were used to induce COPD model, depression model, respectively, and the both were applied for the comorbidity model. Learning and memory deficits were assessed by Morris water maze (MWM) test. The activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) in serum and hippocampus tissue were determined by Xanthinoxidase method and Thiobarbituric acid reaction (TBAR) method, respectively. Results The results of pulmonary histology, lung function, open-field test and sucrose consumption demonstrated the comorbidity models of COPD and depression in elderly rats were successfully established using smoking and CUMS with solitary support. Compared with the elderly control group, the group of COPD with depression had obviously longer time of latency and longer travel distance to reach the platform in MWM test (LSD-t=-10.116, P=0.000; LSD-t=-6.448, P=0.000). The SOD activity in serum and hippocampus decreased significantly (LSD-t=2.629, P=0.014; LSD-t=2.215, P=0.044) and the MDA content in serum and hippocampus increased significantly (LSD-t=-2.140, P=0.042; LSD-t=-2.070, P=0.049) in elderly COPD with depression group. Conclusions COPD in comorbidity of depression could induce spatial memory deficit in old rats. The mechanisms might be related to the overloaded and free radical metabolic imbalance. These results suggest a potential therapeutic target for comorbidity of COPD and depression in geriatric patients.

CsNO3/SiO2 catalysts were prepared using an impregnation method, and were applied in the vapor phase catalytic synthesis of vinylidene chloride (VDC) from 1,1,2trichloroethane (TCE). The influence of reaction temperature on the deactivation of CsNO3/SiO2 catalysts was investigated in detail. It was found that low reaction temperatures ( 400 ° C) result in a high and stable catalytic activity. During the dehydrochlorination process, CsNO3 species were transformed into CsCl, and coke was formed and deposited on the catalyst surface. However, the chemical change of the Cs species and deposited coke were not the main reason for the deactivation of CsNO3/SiO2 catalyst. Some chlorine-containing species (organic products or HCl) were formed during the reaction and were difficult to desorb from the catalyst surface, which accounts for the 510 靳燕霞等:气相法合成偏二氯乙烯的高稳定CsNO3/SiO2催化剂 No.2 1 引 言 偏二氯乙烯 (VDC)主要用于聚偏二氯乙烯 (PVDC)树脂和乳胶的合成单体 -。PVDC具有优 良的隔氧性和保味性,非常适合熟食保鲜冷藏和 微波炉直接加热的覆盖,保鲜效果远高于聚乙烯 (PE)等同类产品,在西方发达国家被誉为“绿色” 包装材料 。随着人们越来越重视食品安全,国内 PVDC市场发展前景非常广阔。目前工业上生产 VDC主要采用浓碱溶液对 1,1,2-三氯乙烷(TCE)脱 HCl的皂化工艺路线 -,但皂化工艺会产生大量 高盐有机废水,面临巨大环保压力,迫切需要开 发新工艺路线以取代皂化工艺。采用TCE气相催 化裂解制备VDC路线,可以有效避免高盐有机废 水等问题,是绿色生产VDC的发展方向 -。 实现 TCE气相催化裂解制 VDC的关键是研 发高效催化剂,目前主要有碱性有机物催化剂和 碱金属催化剂。Mochida等 利用硅胶负载有机胺 1,8-二氮杂双环[5.4.0]十一碳-7-烯(DBU)气相催化 TCE脱HCl,得到VDC选择性 90%,但TCE稳态 转化率非常低(5%)。Fujitsu等 用硅胶负载二苯并18-冠醚-6(B18)和KCl的配合物(KCl-B18)作为催化 剂,进行TCE气相脱HCl反应,得到VDC选择性 为90%左右,TCE稳态转化率小于25%,并指出脱 氯反应中产生的HCl难以脱附,是造成催化剂失活 的主要原因。Serhuchev等 将负载在活性炭上的 苯并咪唑作为催化剂进行TCE气相催化脱HCl,得 到VDC收率为30%-50%。 在碱金属气相催化 TCE脱 HCl制 VDC研究 中,Zoltanski与其合作者 -比较了不同种类的 碱金属盐催化剂,发现采用硅胶负载铯盐具有较 好的催化性能。袁向前 ,王越 及金海龙 在气 固相催化裂解TCE方面也取得了一些成果。蒋鹏 13 利用氧化铝负载碱金属Cs催化裂解TCE时,得到 VDC的选择性为 89%,TCE的转化率为 12%,指 出催化剂表面结焦(炭)是失活主要原因。王越 对 氯化钡、果壳活性炭、石墨三种催化剂的性能进 行了比较研究,发现石墨催化剂表现出良好活 性,TCE稳态转化率可达11%。 在负载型碱金属气相催化TCE脱HCl制VDC 研究中,Mochida与其合作者 -取得了一系列成 果。Mochida等 用硅胶负载CsCl气相催化TCE脱 HCl时,得到TCE的转化率为 26%和VDC选择性 90%。Mochida等 发现 CsCl/SiO2气相催化裂解 TCE反应时,350 °C脉冲反应可以获得TCE转化 率和VDC选择性均为 90%,但在连续反应中TCE 转化率迅速降低,认为HCl难以脱附是CsCl/SiO2 催化剂失活的主要原因。Mochida等 比较了硅胶 负载不同 Cs盐催化裂解 TCE制 VDC反应,如 CsCl、CsNO3、CH3COOCs、Cs2CO3、Cs2SO4等, 发现CsNO3具有较好的催化活性,CsNO3在脱氯化 氢反应中变成CsCl,但没有说明CsCl的作用是促 进催化活性或降低催化活性。Mochida等 利用Cs 交换的ZSM-5沸石分子筛催化剂进行TCE气相裂 解反应,得到CsOH和Si羟基为催化活性中心,当 CsOH转变为CsCl后就失去了催化活性。 国内外至今没有气相催化裂解TCE工业化生 产VDC的报道,其中一个重要原因是气相裂解 TCE催化剂存在严重的失活问题。根据前述文献 可知,气相裂解TCE催化剂失活的可能原因有三 种:一是反应后产生CsCl物种 ,二是催化剂表面 积炭 ,三是反应中产生的HCl难以脱附 。为了 探讨碱金属催化剂失活的本质原因,以期得到一 种高稳定的碱金属催化剂,本文以CsNO3为前驱体 制备了CsNO3/SiO2催化剂,重点考察反应温度等 对气相裂解TCE脱HCl反应影响,结合热重分析 (TGA)、X射线衍射(XRD)和O2程序升温脱附(O2TPD)等物理化学表征手段,探索导致CsNO3/SiO2 催化剂失活的关键因素。 2 实验部分 2.1 催化剂制备 主 要 化 学 试 剂 : 1,1,2三 氯 乙 烷 (TCE, deactivation of CsNO3/SiO2 catalysts at low reaction temperatures. High temperature treatment (550 °C) in a non-oxidizing atmosphere could remove the contaminants and regenerate the catalysts completely. The life test of CsNO3/SiO2 catalyst was carried out at 400 °C for 100 h. The TCE conversion and the selectivity to VDC remained stable at 98% and 78%, respectively, showing good prospect for industrial applications.

Drought is a major disturbance that greatly influences the structure,composition,dynamics and primary production of a forest.Since drought frequency and strength are predicted to increase in the future,understanding the response of natural forests to drought is crucial for predicting the performance of forests under global climate change.In late 2009 and early 2010,a severe drought(rainfall anomaly) occurred in Southwest(SW) China.This severe drought event had a large impact on the regional agriculture and economy of this region,and attracted great attentions of scientists and the public.It has also been recognized as the most severe drought of a century.However,the impacts of this severe rainfall anomaly on natural ecosystems were not well assessed.The objectives of our study were(1) to evaluate the impacts of this rainfall anomaly on forest canopy and litterfall of natural forests in this region,and(2) to establish the relationship between climatic factors and litterfall for natural forests in this region.In the present study,we compared the litterfall and its different components,as well as the leaf area index of different forest layers of an evergreen broadleaf forest onAilao Mountain between the 2010 unusual drought and the previous year drought with normal rainfall amounts.We also analyzed the relationship between litterfall and climatic factors,including annual mean temperature,annual rainfall,and annual number of rainy days.No significant difference was found in annual litterfall between 2010 and the previous years.However,annual leaf fall,dry season litterfall,and dry season leaf fall in 2010,were higher than those in any previous year.Dry season leaf fall in 2010 was 35.2%(0.81 t/hm2)higher than the average during normal years.Notably,the annual fall of epiphytic mosses in 2010 was a historical minimum.No difference was found in leaf area index of the overstorey and understoreylayers between 2010 dry season and 2005 dry season(a year with a normal rainfall amount).However,leaf area index of the herbaceous layer in 2010 dry season was significantly lower than that of the 2005 dry season.Therefore,although the regional rainfall anomaly in early 2010 increased leaf fall in the dry season,it did not significantly influence the canopy leaf area index.The growth of the herbaceous layer and the epiphytic mosses,howeverwere significantly affected.A significant positive relationship between annual litterfall and annual rainfall,as well as a negative relationship between dry season litterfall and dry season rainfall were found.There was no relationship between annual litterfall(or its components: leaf,stem,epiphytic mosses) and mean annual temperature.Therefore,the primary production and litterfall of this subtropical forest is determined by rainfall rather than by temperature.This pattern is different from the result from a previous study in Northeast China,showing that forest litterfall is mainly determined by mean annual temperature.This could be because subtropical forests are relatively warmer than the temperate forests in Northeast China,and temperature is not a major limiting factor on the forest primary production and litterfall of subtropical forests.This relationship could be further tested in other subtropical forests to reveal more general patterns.

Mn-doped ZnS nanoparticles were prepared by the Sol-Gel process in this paper,and the influence of doping ion concentration on crystal structures and luminescent properties of ZnS:Mn nanoparticles was discussed.The structures of the samples were characterized by an X-ray diffractometer(XRD).The results show that the as-prepared ZnS:Mn nanoparticles belong to the cubic sphalerite structure.The parvafacies do not occur when Mn2+-doping concentration reaches 6% and the average particle sizes of nanoparticles decrease with the increase of doping concentration.Photoluminescence(PL) spectroscopy and fluorescence spectrum results show that the emission wavelengths of ZnS:Mn nanoparticles around 590 nm can be adjusted by changing the concentration of the ions.In addition,the influence of temperature on morphology and luminescent properties of nanoparticles was studied.The result observed from a high resolution transmission electron microscopy(HRTEM) shows that the average particle sizes of ZnS∶Mn samples increase to about 20 nm after ageing for 1 h at the temperature of 50 ℃.The heating ageing is beneficial to Mn2+ fluorescence produced at 590 nm for ZnS∶Mn nanoparticles.

A nonimaging optical design method is proposed based on edge ray principle and ellipse flow-line theory.And a Fresnel reflector for uniform lighting LED tubes is designed through three steps: energy equipartition of LED source,target-source foci map and optimization of optical simulation.The complex relationship among the LED source,reflector and target surface is analyzed,which is helpful to optimization of the design of LED illumination.Results show that the uniform of irradiance on LED tube surface is more than 0.93,and the glare is decreased obviously.

Water-use efficiency(WUE) is crucial to plant survival,yield and vegetation dynamics.Many researches trended to reduce water use by more crop per drop.Althoughmuch progresses have been achieved in determining the physiological mechanisms of WUE,there is few report on the genetic controls of WUE.The first gene ERECTA,which t promotes WUE,was shown to decrease stomatal density and be involved in the positive regulation of photosynthetic capacity. The EPIDERMAL PATTERNING FACTOR 1(EPF1) gene identified in Arabidopsis is expressed specifically in stomatal cells and precursors.EPF1 controls stomatal patterning through the regulation of asymmetric cell division,its activity depends on the TOO MANY MOUTHS receptor-like protein and ERECTA family receptor kinases,suggesting that EPF1 provides a positional cue interpreted by these receptors.A mutation of EPF1 results in increased stomatal density and violation of the one-cell-spacing rule(clustering of stomata).However,there is no report on the relationship between AtEPF1 and WUE. The cottonwood poplar,Populus deltoides×Populus nigra,is one of the most important species in large-scale forestation in China.However,its high water consumption is a key factor limiting its growth in arid and semiarid regions.Identifcation of genes increasing WUE in this species is important for understanding stress responses and improvement of this species. In this study,microarray analysis between poplar genotypes NE-19(P.nigra×(P.deltoides×P.nigra)) with the higher WUE and DN-2(P.deltoides×P.nigra) with a lower WUE,was performed.PdEPF1 from NE-19,one of the WUE-related genes,was identified,strongly expressed in immature leaves and roots,but not in senescent leaves,functional leaves and the stem.This gene is strongly induced by drought,abscisic acid and high salt levels,and enhanced by gibberellic acid.To unvarel the mechanism responsible for the inducible expression of PdEPF1 by different stresses,a 1090-bp PdEPF1 promoter fragment was isolated by the adaptor PCR with reference to the transcriptional start site determined from the PdEPF1 cDNA sequence.The PdEPF1 promoter contains CAAT and TATA motifs located at nucleotides-204 and-35 relative to the transcriptional start site,respectively.Each of these motifs has characteristics of eukaryotic gene promoters.Interestingly,,the 1090-bp promoter region contained several motifs based on the computer prediction,such as a W-box(a GA-responsive element),an MYC binding site,an early response to dehydration binding site,and a controlling guard cell-specific gene expression binding site.This indicate,that the stress-inducible expression of PdEPF1 is regulated at the level of transcription.

Southwest China experienced the most severe drought in 100 years in the late 2009 and early 2010.The effects of this severe drought event on forest ecosystems in this region were un-assessed.The aims of this study were(1) to assess if the evergreen broadleaf forest in Ailao Mountain,Southwest China,experienced water deficits in the 2010 rainfall anomaly event;(2) to understand the contribution of forest water storages in mitigating the effects of rainfall anomaly events;and(3) to assess the effects of logging on the water-holding capacity of an ecosystem.Water status of soils and major tree species from a primary evergreen broadleaf forest in Ailao Mountain were monitored in the 2010 dry season.Soil and litter water-holding capacities of a primary forest and a secondary Yushania-Pteridium shrub-land formed after logging and burn were compared.Inter-annual and seasonal variations in soil groundwater table and relative water content of the forest and the Yushania-Pteridium shrub-land were also analyzed.Trees in the evergreen broadleaf forest did not experience water deficits even in the driest month(predawn leaf water potential was higher than-0.5 MPa),and the photosynthetic performance of the trees did not show symptom of long-term depression(predawn maximum quantum efficiency of Photosystem II was higher than 0.80).Soil water content and groundwater table depth of the forest reached an historical minimum during the 2010 Southwest China rainfall anomaly event,however enough soil water was still available for plants during the driest month of 2010(water potential of the soil layer where the roots were growing was still higher than-0.5 MPa).The soil water potential of the evergreen broadleaf forest was higher than the Yushania-Pteridium shrub-land,suggesting better water availability for plants in the primary forest compared to the secondary Yushania-Pteridium shrub-land.The relatively high soil water availability of the primary evergreen broadleaf forest during the rainfall anomaly event is because of its good water-holding capacity,which allows sufficient rainfall in the wet season to be stored in the soil,and to be available to plants in the dry season.The soil water-holding capacity,especially noncapillary water-holding capacity of the evergreen broadleaf forest soils in Ailao Mountain was higher than that of the Yushania-Pteridium shrub-land soils,and higher than those of some other secondary forests in this region.In addition,the abundant litters in the forest floor also contribute to the water storage function of the forest through holding water,preventing evaporation,and decreasing surface runoff.The seasonal dynamics in ground water table and soil relative water content also suggest a larger soil water-storage-pool size of the forest than that of the Yushania-Pteridium shrub-land.In conclusion,the evergreen broadleaf forests in Ailao Mountain possess a strong water storage function,and the sufficient ground water and soil water storages mitigated the shortage of rainfall in dry seasons and in severe rainfall anomaly events.Therefore,our study suggests the irreplaceable role of primary forests in mitigating the effects of rainfall anomaly events,and the importance of protecting primary forests in enhancing the capacity of this region in coping with rainfall anomaly events.

The CdSe/ZnS-quantum-dot doped fiber(QDF) in an ultraviolet(UV) curable adhesive background is manufactured in this study.The photoluminescence spectra are measured in different fiber lengths and with different doping concentrations,and absorption coefficient of the QD in such a background is also determined.There is evidence to show that the PL-peak intensity depends on both the doping concentration and the fiber length.The UV curable adhesive can be a desirable choice for preparing the QDF in laboratories due to small absorption,low shrinkage factor,matching fiber-cladding refractive index,and steady optical property.