A wind tunnel study of aeolian sand transport on a wetted sand surface using sands from tropical humid coastal southern China     

Qingjie Han  Jianjun Qu  Kongtai Liao  Shujuan Zhu  Kecun Zhang  Ruiping Zu  Qinghe Niu 《Environmental Earth Sciences》2011,64(5):1375-1385

This article reported a wind tunnel test of sediment transport related to surface moisture content and wind velocity using sands from tropical humid coastal area. A 1 mm-thick portion of surface sand was scraped using a self-made sediment sampler, and the gravimetric moisture content was determined. Sand transport was measured via a standard vertical sand trap with a 60 cm height. The result shows that the sand transport profile above the wet surface can be expressed with an exponential equation. In general, the influence of moisture content on sand transport profile mainly focuses on the bottom of the blowing sand cloud. Meanwhile, with moisture content increased, total sand transport dropped, and a relatively larger proportion is transported at greater heights. The vertical movement of particles on higher moisture surface (0.587% < M < 1.448%) is more sensitive to moisture content variation as compared to those on low wet surface (M < 0.587%), total sand transport rate tends to be rather low (0.99 g cm⁻¹ s⁻¹) when M > 1.448%. The total sand transport rate varying with moisture content is divided into three regions of differing gradient at the moisture contents of 0.587 and 1.448%. The gradient of the curve reflected the different influences of the various water forms in surface sediments. The higher moisture surface (M > 1.448%) merely functions as a transport plain for the saltation material. Surface moisture content was the dominant control factor for saltation activity between the moisture contents of 0.587 and 1.448%, wind velocity could resume control saltation after the surface dried to the extent (M < 0.587%).  相似文献   

江苏省煤炭资源保障程度及勘查研究   总被引：1，自引：0，他引：1  

邱增果  孟运平  廖家隆  王可新  丁磊 《中国煤炭地质》2011,(10):75-76

通过对江苏省煤炭需求和资源保障程度的分析,对省内资源潜力进行了预测评价,提出了煤炭资源勘查近期和中长期勘查部署方案。建议将赋有优等资源的徐沛区作为下一步工作重点区域,尤其是资源量较多的区域,更应优先考虑;苏南区预测储量有限,且分布零散,含煤性差,近期可不考虑投入工作,已有的工作成果可作为中长期远景规划的依据。  相似文献   

新型PTH-Ⅵ型气象参数测量仪的研制     

欧同庚  项大鹏  邓涛  廖成旺 《大地测量与地球动力学》2011,31(Z1):165-167

介绍一种新型气象参数测量仪的主要技术指标和功能特点.该仪器使用了高准确度的HD9008TR温湿度传感器、MS5534C气压传感器,采用先进的电子线路设计,具有准确度高、稳定性好、可扩展性强、性能价格比高等特点,满足常规气象监测.  相似文献   

沈阳地区大雾天气的UPS订正预报方法     

路爽  董秋婷  孟鹏  李大为  廖国进  赵凤 《气象科技》2013,41(5):878-882

选用2005-2009年沈阳地区5个气象站点的气象资料,总结了沈阳地区雾天的时空分布规律.沈阳地区一年中近一半的时间出现轻雾,大雾年平均16.4天;轻雾和大雾的季节分布都呈夏、秋季多,春季少的态势;大雾多发时段在清晨.在数值预报的基础上,利用UPS预报方法,进一步做出大雾天气订正预报,建立沈阳地区大雾天气UPS订正预报方法.当数值预报有大雾时,如T-Txover（最高气温出现时段温度露点差）≤5℃则可预报有大雾,当-4℃＜T-Txover≤5℃时可预报未来会出现能见度小于等于500 m的浓雾;如T-Txover≤-4℃则预报未来会出现能见度小于等于200m的强浓雾.如T-Txover＞5℃则有暖湿平流时预报有大雾,无暖湿平流时预报不会出现大雾.  相似文献   

北方土地利用变化对中国夏季气候可能影响的敏感性试验   总被引：1，自引：0，他引：1  

李建云  陈军  李华  屈述军  廖海强 《气象与减灾研究》2013,(1):10-17

为考察中国北方地区当代土地利用变化对中国夏季气候的可能影响,以区域气候模式RegCM3为模拟工具,利用1992年和1999年的土地利用资料,进行了中国地区植被覆盖变化的敏感性试验。结果表明,中国北方地区土地利用/植被覆盖的改变,将通过影响大气环流和改变陆地—大气或植被—大气之间的能量平衡状态等,对降水和气温等产生较大影响。  相似文献   

Treatment of Cr(VI) contaminated water with Pannonibacter phragmitetus BB     

Yangyang Wang  Bing Peng  Zhihui Yang  Chongjian Tang  Yuehui Chen  Qi Liao  Yingping Liao 《Environmental Earth Sciences》2014,71(10):4333-4339

Pannonibacter phragmitetus BB was utilized to treat hexavalent chromium [Cr(VI)] contaminated water. Cr(VI) concentration of the contaminated water (pH 10.85) was 534 mg/L. With the inoculum size ranging from 1 to 20 %, P. phragmitetus BB completely reduced Cr(VI) within 27 h when the initial medium concentration exceeded 20 g/L. The lag time of bio-reduction by Cr(VI)-induced cells was 24 h, which was longer than the non-Cr(VI)-induced cells. Under the agitation condition, an obvious bio-reduction lag phase existed and Cr(VI) was completely reduced within 24 h. However, the lag phase was not observed under the static condition, Cr(VI) was reduced continuously after inoculation and Cr(VI) was completely reduced after 27 h incubation. The main chromium components after Cr(VI) reduction were Cr(OH)₃, Cr₂O₃ and CrCl₃. The results of this study are fundamentally significant to the application of P. phragmitetus BB in the treatment of Cr(VI) contaminated water.  相似文献   

Seasonal and regional differences in long-term changes in large mesozooplankton (>505 μm) biomass and abundance in a semi-enclosed subtropical bay     

Du  Ping  Jiang  Zhibing  Zhu  Yuanli  Liao  Yibo  Chen  Quanzhen  Zeng  Jiangning  Shou  Lu 《中国海洋湖沼学报》2021,39(6):2281-2294

Journal of Oceanology and Limnology - Obvious spatiotemporal heterogeneity is a distinct characteristic of ecosystems in subtropical bays. To aid targeted management and ecological restoration in...  相似文献   

广东省市际边界城镇发展的空间类型划分     

廖开怀  陈姝卉 《热带地理》2022,42(3):431-443

利用中国县域统计年鉴（乡镇卷）和中国GDP空间分布公里网格数据集等各类数据,采用因子分析、莫兰指数和GIS分组分析法,对广东省市际边界城镇发展的空间类型进行定量的实证研究。结果表明,广东省市际边界城镇空间结构由公共服务设施与旅游资源类、企业与人口集聚类、生态本底资源类、人民生活水平类以及边缘艰苦类5个主成分因子构成,不同主因子的空间关联性存在差异,其中生态本底资源类和企业与人口集聚类主因子的空间关联性最强,而边缘艰苦类主因子的空间关联性最弱。市际边界城镇的空间发展类型可以划分为高生活水平型发展强镇、产业与人口集聚型发展强镇、产业与公服配套型发展强镇、公服滞后型发展强镇、生态发展型一般镇、生态与旅游型发展一般镇、边缘山区型发展弱镇7类。自然资源禀赋与区位、社会经济发展水平和产业结构、历史基础、政府政策和文化差异为影响市际边界城镇发展空间类型的5大因素。  相似文献   

The spatial pattern and governance of Zhongyuan Urban-Rural System in its development trajectory     

Fu  Haiyue  Wang  Yan  Mao  Liang  Hong  Nana  Wang  Zhaoya  Zhao  Shuchang  Liao  Chuan 《地理学报(英文版)》2022,32(7):1261-1280

Journal of Geographical Sciences - It remains unclear on how transportation network interacts with economic network in an urban-rural agglomeration, while such knowledge is crucial for urban-rural...  相似文献   

新疆卡拉麦里上-中泥盆统间角度不整合和346.8 Ma后碰撞火山岩的意义   总被引：2，自引：0，他引：2       下载免费PDF全文

王富明  廖群安  樊光明  程雯娟  田健  陈帅  吴魏伟  胡朝斌 《地球科学》2014,39(9):1243-1257

在东准噶尔卡拉麦里地区的五彩湾一带出露一套具磨拉石特征的火山沉积建造, 下部为具磨拉石特征的砾岩、砂岩, 上部为一套中基性的火山熔岩夹中酸性的火山凝灰岩.1:20万卡拉麦里山幅将其归入下石炭统松喀尔苏组.通过1:5万地质调查研究发现, 该火山沉积建造底部以一套粗砾岩高角度不整合于下-中泥盆统卡拉麦里组之上, 含晚泥盆世植物化石Prelepidodendron sp.(先鳞木), 中上部火山岩LA-ICP-MS锆石U-Pb年龄为346.8±3.3 Ma, 且被年龄为341.1±4.0 Ma~340.9±5.1 Ma后碰撞花岗岩侵入, 表明其形成时代为晚泥盆世-早石炭世, 时代上对应于北准噶尔地层分区的上泥盆统克安库都克组.该套地层中上部的火山岩的岩石组合为玄武岩、玄武安山岩、夹少量的流纹质凝灰岩, 岩石化学特征上属钙碱性-高钾钙碱性系列, (La/Yb)_N=2.97~6.66, Nb、Ta亏损, 部分样品Zr、Ti弱显亏损, Nb/U、Ce/Pb比值分别为7.43~20.88、3.17~12.45.地球化学特征表明其兼具板内火山岩和弧火山岩的某些特点, 形成于后碰撞伸展环境, 是卡拉麦里洋盆于晚泥盆世之前闭合后后碰撞岩浆活动的产物.这一研究成果对广为关注的卡拉麦里洋盆的闭合时间进行了很好的限定.   相似文献