基于城市腹地的乡镇通达性的时空格局及其演化——以湖北荆州市112个乡镇为例

行政边界对路网的分割效应和以出行方向机会均等为前提是当前通达性研究中的两大问题。基于2000~2011年荆州市城乡道路网空间数据库,自下而上揭示了2000~2011年荆州市乡镇通达性的时空格局及其演化特征:(1)基于城市腹地范围的乡镇通达性评价较好的模拟了乡镇的出行意愿,且实现了区内通达性与区际通达性的综合。十多年间,交通网络建设带来的城市腹地时空压缩效应显著:荆州市乡镇地域所属地级市腹地格局由荆州"一城主宰"演变为荆州和岳阳"两城瓜分",所属县级市腹地格局也经历了由"荆州独享"到"周边共享"的发展历程;(2)十多年间,荆州市乡镇通达性空间分布基本遵循距离衰减律,呈现以荆州城区为中心的环状分布格局,且时序上表现出微观动态性和宏观稳定性特征:一是,通达性空间分布呈现由低水平集聚向优化均衡的动态性发展趋势。二是,乡镇通达性空间分布结构由核心-边缘向等级圈层结构的演进。三是,乡镇通达性发育具有时空惯性,呈现显著的快速干道指向性;(3)十多年间,荆州市乡镇通达性发育呈现出"单核单轴弱扩散"→"单核多轴强扩散"→"双核多轴全扩散"的空间演化模式。     

滇池流域主要农业产品水足迹空间格局及其环境影响测度

科学合理的评估农业产品水资源消耗及其环境影响对保护区域农业生产安全和水资源合理配置具有重要意义.本文以滇池流域为例,耦合水足迹和生命周期评价方法,对流域内2005—2011年主要农业产品水足迹空间格局进行分析,并对其环境影响进行测度.结果显示:滇池流域主要农作物和动物产品年平均水足迹分别为4.88×108m3·a-1和8.97×108m3·a-1,动物产品总水资源消耗大于农作物产品.动物产品水足迹的人类健康和生态系统质量总环境影响高于农作物,但资源消耗总环境影响要低于农作物,各区县产品水足迹环境影响值最大的为猪肉、水稻和玉米.各区县主要产品水足迹及其环境影响空间差异显著,嵩明县和晋宁县的产品水足迹环境影响最高,城区则较低.本文最后提出:评价一种产品对区域水资源的可持续性影响时,不仅要考虑产品耗水量也应考虑产品对水资源产生的潜在环境影响大小,应从水资源管理和生命周期角度综合考虑.水资源量少的地区,应侧重选择水资源消耗量小的产品,水量充沛地区则应选择对人类和生态产生影响小的产品.     

Gas–Liquid Two-Phase Flow in a Mini-Channel with Water Infiltration Continuously Along the Flow Direction

Characteristics of air–water two-phase flow pattern in a square-mini-channel were investigated experimentally. One sidewall of the flow channel was made of a permeable porous media. Air was fed into the channel from its inlet, while liquid water was injected uniformly into the channel along the permeable sidewall. Based on the results of visualization, the typical flow patterns encountered in the conventional co-current gas–liquid two-phase flow were not observed in the present work. Flow patterns of this special gas–liquid two-phase flow were catalogued, and the influence of gas flow rate and liquid infiltration rate on flow patterns was also analyzed. The results also indicate that the channel differential pressure on both sides brings obvious fluctuations when the liquid is infiltrated. The frequency of this fluctuation depends not only on the amount of liquid infiltration but also relies on the gas flow rate significantly. However, the amount of liquid infiltration barely affects the fluctuation in the amplitude of the pressure differential.     

关于建立藻类自动检测、分类与存储系统的方法的研究

基于计算机视觉和模式识别理论,研究自动和便捷的的藻类检测分类系统,实现提高检测的准确性和工作效率,实现水生生物的自动检测、分类与存储。     

BIOFOR处理混装制剂类制药废水工程实例

介绍了BIOFOR反应器在江西某医药集团混装制剂废水处理中的工程应用。采用自然挂膜和接种挂膜相结合的方式快速启动BIOFOR池。BIOFOR池处理混装制剂废水具有良好的效果、较高的耐冲击负荷能力、运行稳定。COD平均去除率达72.45%,NH3-N平均去除率达56.8%。BIOFOR池出水可稳定达GB 21908—2008《混装制剂类制药工业水污染物排放标准》。BIOFOR池处理混装制剂废水的最佳运行气水比为5∶1。反冲洗宜采用水气联合反冲洗。     

华北平原灰霾天气下大气气溶胶的单颗粒分析

为分析灰霾期间单颗粒气溶胶化学组成和混合状态,于2014年12月9日—2015年1月10日,使用单颗粒气溶胶质谱仪（SPAMS）表征华北平原郑州市中牟县的气溶胶颗粒.结果表明:灰霾期（H1:20141213T19:00—20141215T10:00;H2:20150102T10:00—20150106T03:00）和清洁期（C1:20141215T18:00—20141217T18:00;C2:20141231T16:00—20150101T20:00）大气颗粒物种类相同,主要分为有机碳（OC）、元素碳（EC）、生物质燃烧颗粒（BB）、元素碳有机碳（ECOC）、钾二次颗粒（K-Secondary）、矿尘（Dust）以及重金属颗粒（HM）7类.C1时间段,ECOC颗粒占比最高,占总颗粒数的49.8%;其次是OC和EC颗粒物,二者分别占总颗粒数的16.5%和10.8%.H1时间段,K-Secondary颗粒的占比（31.3%）最高;其次是OC和EC颗粒,二者分别占总颗粒数的23.1%和20.2%.清洁期与灰霾期质谱差分结果表明,清洁期颗粒物中含有C₃H+、C₄H₃+、C₅H₃+等有机碳碎片峰,而灰霾期颗粒物中NO₃-、HSO₄-、NO₂-等组分的信号强度显著大于清洁期.混合状态分析表明,从清洁期到灰霾期的过程中,主要颗粒物与NO₃-和HSO₄-的混合程度显著增强.清洁期与灰霾期单颗粒化学组成与混合状态的对比分析表明,清洁期新鲜排放的含碳气溶胶在灰霾期不断老化,单颗粒中二次无机组分增加,气溶胶整体老化严重.此外,灰霾期（H2）EC颗粒占总颗粒数的比例增至18.1%,并且与NO₃-、HSO₄-二次组分的混合状态增强,使平均能见度降低为4.0 km.研究显示,郑州大气能见度主要受化学组分、颗粒物混合状态和污染物质量浓度的影响.      

基于标量场协同的柴油机油气混合特性研究

目的研究过量空气系数对柴油机缸内油气混合特性的影响情况。方法基于柴油机缸内燃油混合气浓度和湍流混合速率两个微观物理场的耦合作用,定义混合协同效率和混合协同度对缸内混合特性进行定量描述。结果随着过量空气系数的升高,燃油混合气浓度场和湍流混合场相互作用的持续时间增长。在过量空气系数1.3~1.6范围内,随着过量空气系数的增加,混合协同效率的峰值逐渐降低。在过量空气系数1.6~2.2范围内,随着过量空气系数的增加,混合协同效率的峰值整体呈上升趋势。结论过量空气系数1.7前后混合协同度的变化规律不同。过量空气系数达到1.7后,随着进气量的增加油气混合质量改善的空间减小。     

水泥土深层搅拌桩在某工程中的设计与应用

结合实际工程介绍了水泥土深层搅拌桩在复杂软弱场地中的设计及应用。     

资源型城市转型效率时空格局及影响因素探析：以陕甘宁能源富集区为例

基于数据包络分析、标准差椭圆和地理探测器方法，引入产业多样化指数和产业专业化指数，综合探讨陕甘宁资源型城市的转型效率、时空格局及其影响因素，得到2011—2020年陕甘宁资源型城市转型绩效综合得分及分布、不同发展阶段资源型城市转型绩效以及三省区各自资源型城市的转型绩效。结果表明：（1）2011—2020年陕甘宁资源型城市转型效率具有显著的时间和空间差异。（2）研究期内陕甘宁资源型城市转型效率空间分布格局基本保持稳定，仍以东西方向为主导。（3）地方财政一般预算内支出、城市建设用地面积、地区生产总值是影响资源型城市转型效率空间分异的主导因子。揭示了研究区资源型城市转型效率的发展演变态势及驱动因素，可为其持续优化转型提供决策依据。     

Impacts of climate change on lakes and reservoirs dynamics and restoration policies

Meteorological-driven processes exert large and diverse impacts on lakes and their water quality; these impacts can be hydrologic, thermal, hydraulic, chemical, biochemical, or ecological. The impact of climate change on Lake Tahoe (California–Nevada) was investigated here as a case study of climate change effects on the physical processes occurring within lakes. The already published trends of meteorological variables were used to assess the effects of global warming on Lake Tahoe dynamics. Records from the period 1969–2002 show that Lake Tahoe has became warmer and more stable. A series of simulation years into the future (i.e., 2000–2040) was established using flows, loads, and meteorology data sets for the period 1994–2004. Results of 40-year simulations show that the lake continues to become warmer and more stable, and mixing is reduced. Possible changes in water quality because of global warming are discussed through inference, although these are not specifically simulated. Many existing problems may be exacerbated due to climate change, yet extreme uncertainty depends on the rate and magnitude of climate change. Therefore, shifts in water quality and quantity due to climate change should be integrated into contemporary planning and management in an adaptive manner, and the research and development of impact assessment methodology should focus on approaches that can handle extreme uncertainty. The general alternatives for lake management due to climate change are discussed. Depending on the specific case, further intensive research is suggested to restore lake water quality.