巴州地区一次大降水过程的分析

对2002年6月16～18日、21日巴州地区出现的大范围的降水天气过程，重点从环流形势、物理量场以及数值预报产品的应用等方面作了初步分析，得出了一些有益的结论。     

Primary Product Distribution from the Reaction of Hydroxyl Radicals with Toluene at ppb NOX Mixing Ratios

A study has been conducted to examine the OH-initiated degradation products of toluene in the presence of sub part-per-million levels of NO_X. The experiments were conducted in a dynamic reactor to minimize the conversion of the aromatic compounds while allowing a sufficient mass of products to be collected for analysis. The major primary products detected in the toluene system (with molar yields) include glyoxal (0.238), methylglyoxal (0.167), o-cresol (0.120), benzaldehyde (0.06), 4-oxo-2-pentenal (0.03), and p-cresol (0.03). Six other reaction products, most being ring cleavage products, were measured at yields below 3%. Corrections for secondary OH reactions with the products were made where necessary. The formation of the cresol isomers was found to be invariant to the NO₂ concentrations which indicates that under atmospheric conditions the initial hydroxycyclohexadienyl radical reaction with NO₂ is a minor process and that most of the reaction occurs with O₂. The product yields found in this study are expected to be representative of those that occur in the urban atmosphere at ambient NO₂ concentrations.     

Using Chlorine Dioxide for Drinking Water Disinfection by the Application of the Chlorite/Chlorine Process

Chlorine dioxide stock solutions for the disinfection of drinking water are made by the application of chlorite/chlorine process in many waterworks. In such cases the stock solution is always characterised by a mixture of chlorine and chlorine dioxide. The disinfection of waters of different origin with a mixture of chlorine dioxide and chlorine showed the formation of odours of different intensity. The reasons are the re‐formation of chlorine dioxide and the formation of odorous disinfection by‐products. Applying the chlorine dioxide for disinfection, its re‐formation caused by the reaction of chlorite with chlorine is the dominant reason of odour formation. When chlorine is used, the formation of odorous by‐products becomes more relevant. In order to quantify the sensitivity of water concerning odour, the odour indicator coefficient OI was defined. The decreased demand of chlorine dioxide by applying chlorine and chlorine dioxide in combination is recognised to be the key in order to avoid the formation of odour after the disinfection of drinking water with chlorine dioxide.     

完全预报（PP）方法在广东冬半年海面强风业务预报中的应用

在进行大量普查分析和统计的基础上, 将最近10年历史天气图的地面气压和有关海面强风代表站的风场资料在日本数值预报模式输出报文的1.25°×1.25°格点分布上进行客观分析, 对比传统的以关键区域划分冷空气入侵路径与广东海面强风的关系, 提出了一套与广东冬季海面强风关系更密切、作用更直接的地面关键区气压场分布特征进行客观定量的分型;根据梯度风原理, 用经验加统计的因子挑选方法, 形成了一套应用日本数值预报模式输出、适用于广东海面强风预报的完全预报(PP)方法。检验和业务试用结果均表明:该方法对广东的海面强风具有较强的预报能力;用完全预报方法做沿海海面强风预报是可行的。     

成都市土壤环境质量及优质农产品基地选区地球化学评价

以成都市土壤第一环境832件样品和土壤第二环境3061件样品53个元素的准确定量测试数据为基础,确定了成都市土壤中13种植物必须的营养元素及有益元素和5种对植物有害元素的背景值和过量限值及不足限值,并以此为基础进行成都市土壤环境质量评价和优质农产品基地选区地球化学评价。     

一次大降水天气过程的特征分析

对巴州地区一次大范围的强降水、冰雹天气作了分析，重点从环流形势、不稳定条件、卫星云图等方面阐明了形成大范围降水的有利条件。指出卫星云图可以提供对中小尺度天气系统的识别和监测，直观反映出大降水，尤其是冰雹的落区，最后，通过对比分析，证明T106产品在预报中的准确性较高，有一定的参考价值。     

GIS数字地图质量子幅抽样方案的探讨

在对数字地图产品实行抽样检验的基本原理和抽样方案的基础上,对数字地图提出了一种新的1/m子幅质量抽样检验方法,并对其原理与方法进行了探讨,同时以特征曲线(OC曲线)分析了这种方法的可行性,这种新的1/m子幅抽样检验方法也可以通过调整已有的整幅抽样方案而获得.     

地质调查产品有效供应理论分析

传统公共经济学中关于公共产品有效供应的分析在理论假设和数学模型上都存在问题。这种理论难以指导现实中公共产品的有效提供,尤其是日益重要的地质调查产品的有效供应。利用一般概率模型和信息经济学模型对地质调查产品的供应进行分析后可以得出对中国地质调查产品有效供应的更清晰的认识。     

“21世纪海上丝绸之路”沿线国家水产品贸易网络分析

水产品贸易是海洋经济的重要组成部分,是保证水产品有效供给、维护渔业产业链的重要措施。优化水产品贸易网络对保障中国粮食安全和扩展国际贸易具有重要意义。文章借助联合国商品贸易数据库,选取2000—2019年“21世纪海上丝绸之路”沿线国家水产品贸易数据,利用社会网络分析方法,测度“21世纪海上丝绸之路”沿线国家水产品贸易网络结构特征,进而分析沿线国家水产品贸易市场结构和产品结构。研究发现：1）2000—2019年“21世纪海上丝绸之路”沿线国家的水产品贸易变化可划分为2个阶段,其中第一阶段（2000—2008年）为平稳增长期,第二阶段（2009—2019年）为波动发展期。2）水产品贸易网络密度逐渐增大,空间集聚和网络凝聚力逐渐增强,网络的可达性不断提高,呈现小世界的特性。3）水产品贸易网络的核心—边缘结构较为稳定,核心国家的贸易联系紧密,贸易额占整体的一半以上,多边、双边贸易流存在差异,贸易网络的空间非均质性特征凸显;地理区位及距离对其组团有间接的影响,社团划分呈现层级性和地理临近组团的特点。4）水产品贸易网络的空间分异特性较为明显,重要节点国家主要集中在中国和东南亚国家,中间中心度高的国家和接近中心度排名靠前的国家具有趋同性,非洲东部及红海沿岸国家的网络中心性影响力较弱。5）在核心国家的水产品市场结构中,中国占据较大份额;国家间的关系变化引起市场结构发生调整;中国水产品进出口品种结构比较单一,进口和出口产品分别主要集中在冻鱼和水产品制品。     

Improved NLDAS‐2 Noah‐simulated hydrometeorological products with an interim run

In North American Land Data Assimilation System Phase 2 (NLDAS‐2) Noah simulation, the NLDAS team introduced an intermediate ‘fix’ to constrain the surface exchange coefficient when the atmospheric boundary layer is stable. In the current NLDAS‐2 Noah version, this fix is used for all stable cases including snow‐free grid cells. In this study, we simply apply this fix to the grid cells in which both stable atmospheric boundary layer and snow exist simultaneously, excluding the snow‐free grid cells as we recognize that the fix in NLDAS‐2 is too strong. We conduct a 31‐year (1979–2009) NLDAS‐2 Noah interim (Noah‐I) run and use observed streamflow, evapotranspiration, land surface temperature, soil temperature, and ground heat flux to evaluate the results, including comparisons with the original NLDAS‐2 Noah run. The results show that Noah‐I has the same performance as NLDAS‐2 Noah for snow water equivalent; however, Noah‐I significantly improved the simulation of other hydrometeorological products as noted earlier when compared with NLDAS‐2 Noah and the observations. This simple modification is being included in the next Noah version used in NLDAS. The hydrometeorological products from the improved NLDAS‐2 Noah‐I are being staged on the National Centers for Environmental Prediction public server. Copyright © 2014 John Wiley & Sons, Ltd.