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Search Results: 1 - 10 of 300223 matches for " <br>胡梦瑶 "
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Variations in leaf functional traits of Stipa purpurea along a rainfall gradient in Xizang,China
西藏紫花针茅叶功能性状沿降水梯度的变化

HU Meng-Yao,ZHANG Lin,LUO Tian-Xiang,SHEN Wei,<br>,张林,罗天祥,沈维
植物生态学报 , 2012,
Abstract: Aims Stipa purpurea is the dominant species in alpine arid and semi-arid grasslands on the Tibetan Plateau. Our objectives are to determine if this species exhibits a strategy shift in its specific leaf area (SLA) to nitrogen (N) concentration relationship along a rainfall gradient and to detect possible effects of environmental factors on related leaf traits. Methods We investigated variations in leaf traits of S. purpurea associated with climatic and soil factors along an east-west transect with a rainfall gradient (69–479 mm) but similar altitudes (4 300–4 700 m). Five locations from east to west are Damxung, Namco, Gêrzê, Mount Qomolangma and Rutog. We measured SLA, mass- and area-based leaf N concentration (Nmass, Narea), leaf density and thickness and soil total N along the transect. Important findings In pooled data, SLA and Nmass varied little with the growing season mean temperature and precipitation and the soil total N concentration. The SLA-Nmass relationship in S. purpurea did not shift between the semi-humid areas (ratio of rainfall to evaporation > 0.11) and the arid and semi-arid areas (ratio < 0.11), although there was a positive correlation between SLA and Nmass across the five locations. Variation in SLA was mainly determined by leaf density in the semi-humid areas and by leaf thickness in the arid and semi-arid areas; both were negatively correlated with SLA. With increasing temperature or declining precipitation, leaf density decreased and leaf thickness increased, leading to non-significant relationships between SLA and climatic factors. The increase of leaf density in the semi-humid areas was correlated with the increase of Narea, but the increase of leaf thickness in the arid and semi-arid areas did not lead to change of Narea, resulting in unchanged Narea along the rainfall gradient. A positive correlation was detected between aboveground biomass and Narea in S. purpurea, indicating that increased Narea may increase plant productivity. Our findings suggest that alpine plants in arid and semi-arid areas may maintain a constant Narea by increased leaf thickness in order to achieve a similar photosynthetic productivity and water use efficiency compared to the relatively humid areas. The relative impacts of leaf density and leaf thickness on SLA shifted between the semi-humid areas and the arid and semi-arid areas, which may provide insight in detecting the threshold of water limitation in alpine grasslands.
脱硫废水中重金属离子去除研究进展
Research Progress of Heavy Metal Ions Removal in Desulfurization Wastewater
 [PDF]

, 许佩, 汪黎东, 刘永春
Water pollution and treatment (WPT) , 2016, DOI: 10.12677/WPT.2016.43013
Abstract:
本文结合脱硫废水水质特征,对脱硫废水中重金属离子去除技术的研究进行了综合评述。介绍了化学沉淀法、螯合沉淀法、流化床法、吸附法处理重金属废水的研究进展,比较了几种方法的优缺点,并对脱硫废水中重金属离子去除技术的发展方向进行了展望。
In this paper, in combination with characteristics of the desulfurization wastewater quality, the tech- nology of desulfurization wastewater removing heavy metal ions from the study conducted a comprehensive review. The article introduces the chemical precipitation, chelating precipitation, fluidized bed method and adsorption method in the research progress of heavy metal wastewater treatment and compares the advantages and disadvantages of several methods. The technology of desulfurization wastewater removing heavy metal ions from the development direction is prospected.
西藏紫花针茅叶功能性状沿降水梯度的变化
, 张林, 罗天祥, 沈维
植物生态学报 植物生态学报 , 2012, DOI: 10.3724/SP.J.1258.2012.00136
Abstract: ?植物叶功能性状与环境因子的关系是近10年来植物生态学的研究热点。该文以广泛分布于青藏高原干旱、半干旱草地的优势植物种紫花针茅(Stipapurpurea)为研究对象,沿降水梯度(69–479mm)系统测定了日土、改则、珠峰、当雄和纳木错5个调查地点紫花针茅比叶面积(SLA)、单位重量和单位面积叶氮含量(Nmass,Narea)、叶密度和厚度等叶功能性状以及土壤全氮含量等因子,试图验证干旱胁迫地区同一物种内SLA-Nmass关系沿降水梯度的策略位移现象是否具有普遍性,并对是否出现策略位移现象提出可能的解释。研究结果表明:1)SLA和Nmass与生长季温度和降水以及土壤全氮含量均没有显著关系,SLA与Nmass的关系在干旱半干旱区(年降水/蒸发比<0.11)与半湿润区(年降水/蒸发比>0.11)之间并没有出现典型的位移现象;2)叶密度是决定半湿润区SLA变化的主导因子,而叶厚度则是干旱半干旱区SLA变化的控制因子,两者与SLA均呈负相关,随着温度增加或降水减少,叶厚度增加而叶密度降低,导致SLA随温度和降水变化不明显;3)半湿润区的叶密度增加引起Narea增加,而干旱半干旱区的叶厚度增加并没有造成Narea的显著变化,导致Narea沿降水梯度没有显著变化;4)紫花针茅地上生物量与Narea具有显著正相关关系,表明Narea的增加有助于提高植被生产力。结果表明,在干旱胁迫下,植物通过增加叶厚度来维持不变的Narea可能有助于保持与较湿润地区相似的光合生产和水分利用效率。叶厚度和叶密度对比叶面积的相对影响在干旱半干旱区与半湿润区之间发生转变,这为进一步检测高寒草地植被的水分限制阈值提供了新思路。
流动-差热吸附量热系统ⅱ.氢型丝光沸石吸附热的研究
,冯福盛,
物理化学学报 , 1987,
Abstract:
流动-差热吸附量热系统ⅰ.装置考察与氢型丝光沸石(hm)-苯体系吸附热的测定
,冯福盛,村*
物理化学学报 , 1986,
Abstract:
基于ARIMA模型的广州市生态足迹动态变化过程
Dynamic changes of ecological footprint based on ARIMA Model for Guangzhou City

付开 徐颂军 马娇娇
- , 2017,
Abstract: 为了解广州市生态可持续问题,运用生态足迹模型对广州市2003—2013年的人均生态承载力和人均生态足迹进行了模拟和分析,在此基础上运用ARIMA模型预测了2014—2020年的生态足迹变化趋势. 结果表明:2003—2013年人均生态足迹呈上升趋势,增幅达到6.7%,人均生态承载力呈下降趋势,人均生态承载力远远小于人均生态足迹,导致生态赤字状态,广州市处于严重不可持续发展状态;2014—2020年人均生态足迹呈上升趋势,2020年达到4.201 8 hm2/人,是2013年的1.02倍,人均生态承载力基本保持不变,人均生态赤字不断增大. 针对广州市严重不可持续发展的现状,提出加大环境生态保护力度、控制人口规模、优化产业结构和转变经济发展方式等实现广州市可持续发展的建议.
:In order to understand the ecological sustainability of Guangzhou, the ecological carrying capacity per capita and the ecological footprint per capita municipality from 2003 to 2013 in Guangzhou is calculated by applying the ecological footprint model. Based on the computed result, the development trend from 2014 to 2020 is also predicted by using ARIMA model. The results show that:the ecological footprint per capita on the rising from 2003 to 2013,an anual rate of 6.7% the ecological carrying capacity per capita is always bigger the ecological footprint per capita,which means the ecological deficit,and Guangzhou city is in serious unsustainable development state.The predicted results show the ecological footprint per capita has been rising from 2013 to 2020 with increasing to 4.066 2 hm2/cap in 2020,which would be 1.02 times than that of 2013,the ecological carrying capacity per capita remained unchanged. Considering the unstable development in Guangzhou, several policy recommendations is proposed to reduce eco-footprint,including optimizing the industrial structure,improving the efficiency of resource utilization,and changing the mode of economic development. Improving the ecological carrying capacity of resources is an effective way to promote environmental and socioeconomic sustainable development
狗肾细胞培养条件优化
Optimization of culture condition for MDCK cell culture

马萍,,李欣?h,
- , 2017,
Abstract: 目的 探讨狗肾细胞培养影响因素,优化狗肾细胞培养条件。方法 将狗肾细胞以1×104的密度接种到96孔板上,改变狗肾细胞的培养条件:不同的温度(35℃、36℃、37℃)、不同的培养基(MEM、DMEM、1640)、不同pH值(pH = 6.4、6.7、7.0、7.2、7.5)、不同浓度的牛血清(0%、2.5%、5%、10%、15%)、不同浓度的L -谷氨酰胺(0、1、2 、4 mmol/L)、不同浓度的4-羟乙基哌嗪乙磺酸 (0、50、100、150 mmol/L)、不同浓度的CO2(0%、5%),每日观察细胞形态变化,并在24、48、72、96、120、144 h加入CCK - 8测450 mm下的OD值,用OD值的倍数绘制MDCK细胞的增长曲线,比较不同生长条件对MDCK细胞增殖的影响。结果 狗肾细胞的最优培养条件为:37℃、5%浓度的CO2、DMEM培养基、pH值6.7~7.2、5%~10%胎牛血清、4 mmol/L - 谷氨酰胺、50~100 mmol/L的4 - 羟乙基哌嗪乙磺酸。结论 可以根据工作需要,调节牛血清浓度和温度高低,来加速或减慢MDCK细胞的增殖速度。
锌K-Alpha X射线组态互相作用计算
Relativistic Configuration Interaction Calculations for the K-Alpha X-Ray of Zinc
 [PDF]

,
Applied Physics (APP) , 2014, DOI: 10.12677/APP.2014.41001
Abstract:
采用结合包含Breit相互作用、量子动力学效应和有限核质量修正的相对论的组态相互作用的方法以及多组态Dirac-Fock方法的能级优化法来计算锌离子的波长、电偶极跃迁速率以及振子强度。利用活动空间扩大法,计算出的类氦和类铍的数据与实验数据符合很好。在此基础上本文给出了准确的锌离子类氦到类氖的跃迁特性。这些数据可以给锌等离子体的能级寿命、布居分布以及平均电荷提供参考。
Relativistic configuration interaction calculations with the inclusion of Breit interaction, quantum electrodynamics and finite nuclear mass corrections have been carried out in the extended optimal level scheme using multi- configuration Dirac-Fock wavefunctions on the wavelengths, electric dipole transition rates and oscillator strengths of Zinc. Through the use of the active space method, the calculated values are compared with the other available data on He-like and Be-like zinc and are found to be in very good agreement with them. In this paper, we give accurate transition properties from Zn XXI through Zn XXIX. These data provide reference value for level lifetime, charge state distribution and average charge of zinc plasmas.
大学生自我概念对社会适应的影响:自我调控的中介作用
Mediation Role of Self-Regulatory between College Students’ Self-Concept and Social Adjustment
 [PDF]

, 陈功香
Advances in Psychology (AP) , 2012, DOI: 10.12677/AP.2012.24034
Abstract: 目的:探讨大学生的自我调控在自我概念和社会适应之间的中介作用。方法:采用田纳西自我概念量表,自我调控问卷和大学生社会适应问卷对320名大学生施测。结果:1) 自我概念、自我调控与社会适应呈显著正相关,大学生自我概念和自我调控能够显著预测社会适应;2) 自我调控在自我概念和社会适应之间的部分中介效应显著。结论:自我概念可以预测社会适应的倾向,自我概念较高者更容易适应社会,自我调控在自我概念与社会适应之间起部分中介作用。
To investigate Self-regulatory fully or partially mediates the relationship between Self- concept and social adjustment. Methods: A total of 320 college students were investigated by Self-regulatory Questionnaires, Self-concept Questionnaires and social adjustment Questionnaires. Results: 1) Self-concept and Self-regulatory was significantly positively related to social adjustment and Self-concept could predict social adjustment positively; 2) The mediatory effect between social adjustment and Self-concept was sig- nificant. Conclusion: Self-concept could predict social adjustment positively and colleges of high Self-con- cept were more easily to adapt social; Self-regulatory mediated the relationship between Self-concept and so- cial adjustment.
汉语方言里的“挑”
Verbs for “Shoulder” in Chinese Dialects
 [PDF]

陈稚,
Modern Linguistics (ML) , 2014, DOI: 10.12677/ML.2014.23014
Abstract:
本文以《汉语方言地图集?词汇卷》133图为依据,讨论930个汉语方言点挑的说法。“担”和“挑”是通行最广的两种优势词形,分别见于510个方言点(453 + 57)和393个方言点(343 + 50)。“挑”主要分布在长江流域以及华北平原和东北地区,“担”则分布在长江流域的南北两翼,两者构成了所谓的“中心—外围”分布。这种地理分布格局是由于南宋以后兴起的“挑”打破了“担”的连续分布格局而造成的。此外值得注意的是客家话的“荷”以及浙西南、赣东北部分吴语的“揭”,分别见于 60 个方言点(56 + 4)和12个方言点(9 + 3)。本文认为吴语的“揭”本字也是“荷”。客家话的“荷”大概是古河洛方言的继承形式,而浙西南、赣东北部分吴语的“荷”则为古江东方言“荷”的残存。
According to the Map 133 in the vocabulary volume of Linguistic Atlas of Chinese Dialects (LACD), this paper discusses the word forms of tiao (shoulder v.) in 930 Chinese dialects locations. The categories dan and tiao, which are most widely distributed, are used in 510 locations (453 + 57) and 393 locations (343 + 50) respectively. Tiao is mainly located in the Yangtze River Basin, the North China Plain and the Northeast China, while dan is located in both sides of the north and the south of the Yangtze River Basin. The two constitute a Center-Periphery Distribution. This particular geographical distribution pattern resulted from the rising tiao breaking the continuous distribution pattern of dan after the Southern Song Dynasty. What is also worth noting is that he from Hakka and jie from the Wu dialects in the southwest Zhejiang and the northeast Jiangxi, are used in 60 locations (56 + 4) and 12 locations (9 + 3). The original character of jie which refers to shoulder is he. He from Hakka may be a form of inheritance of the ancient He-Luo dialect, while he from the Wu dialects in the southwest Zhejiang and the northeast Jiangxi is the remnant of the ancient Jiangdong dialect.

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