Dissipation of Contaminants of Emerging Concern in Biosolids Applied to Nonirrigated Farmland in Eastern Colorado

In 2007, a 1.5‐year field‐scale study was initiated by the U.S. Geological Survey to evaluate the dissipation of contaminants of emerging concern (CECs) following a first agronomic biosolids application to nonirrigated farmland. CECs with the greatest decrease in concentration in the surface biosolids at 180 days post‐application included indole, d‐limonene, p‐cresol, phenol, and skatol. CECs that were present in the largest concentration in 180‐day‐weathered biosolids included stanols, nonylphenols, bisphenol A, bis(2‐ethylhexyl) phthalate, hexahydrohexamethyl cyclopenta‐benzopyran (HHCB), and triclosan. CECs that were detected in pre‐application soil were 3‐beta coprostanol, skatol, acetophenone, beta‐sitosterol, beta‐stigmastanol, cholesterol, indole, p‐cresol, and phenol, most of which are biogenic sterols or fragrances that have natural plant sources in addition to anthropogenic sources, yet their concentrations increased (in some cases, substantially) following biosolids application. Preliminary data indicate the nonylphenols (including NPEO1, NPEO2), OPEO1, benzo[a]pyrene, diethyl phthalate, d‐limonene, HHCB, triclosan, and possibly 3‐beta coprostanol, skatol, beta‐sitosterol, cholesterol, indole, and p‐cresol, migrated downward through the soil by 468 days post‐application, but indicated little uptake by mature wheat plants. This study indicates that some CECs are sufficiently persistent and mobile to be vertically transported into the soil column following biosolids applications to the land surface, even in semiarid regions.     

南京、新沂地震台地电地磁同场观测对地磁干扰的改善

根据南京地震台一系列地电地磁同场观测时对地磁干扰的研究试验结果,南京地震台在新地电场地建设和新沂地震台在地电外线路的改造中,都注意使供电线路的“单线段”远离地磁观测室,使地电对地磁的干扰得到了明显的改善。     

中国国土空间规划法律体系：问题检视与框架重构

通过对现行空间规划法律规范的体系性检视,发现由于立法策略、部门立法以及规划立法依附性等原因,其存在顶层立法付之阙如、外部结构冗杂扁平、内部规范碎片冲突等问题。遵循领域法、发展法以及体系化逻辑,国土空间规划立法应以现实问题与治理现代化为导向,在突破部门法壁垒的同时注重法制发展的接续性,力求实现国土空间规划法律体系的形式协调与价值融贯。构建国土空间规划法律体系,对内应确立国土空间规划法的基本法地位并辅之以配套立法,对外应注重与国土空间开发保护法等相关立法、国土空间政策与技术标准的衔接,最终构架起一个主轴明确、层次严密、差序有别的圆锥状国土空间规划法律体系。     

交变电场-铁改性生物质强化城市污泥深度脱水

为了实现城市污泥的深度脱水,采用铁改性生物质作为骨架构建体联合交变电场电渗透技术处理污泥,以单因素实验为基础,探究了该联合技术对污泥脱水性能的影响,并通过表面响应法优化了污泥脱水的工艺参数.将玉米秸秆使用浓度为0.03g/mL的FeCl₃溶改性后与污泥混合,当采用不等占空比为4.33:1的交变电场,电压为17.22V/cm,改性生物质投加量为96.81mg/g DS,改性生物质含水率为61.91%,生物质粒径为1.05mm,阴阳极间距为2.10cm时,可以得到含水率为58.21%的脱水污泥,脱水能耗为0.0148kW·h/kg RW (脱除水分).脱水污泥的扫描电镜表征结果显示,铁改性生物质可以在污泥中起到良好的骨架支撑作用,有利于提高污泥的机械强度和可渗透性;热重分析显示,脱水后污泥的上、下层燃烧过程可划分为析出自由水和束缚水阶段,析出和燃烧挥发分阶段、分解无机盐阶段,添加铁改性生物质的脱水污泥有机质含量更高,燃烧得更快.     

Thermodynamic coupling characteristics in hybrid (dry/wet) cooling system

A hybrid cooling system consisting of both a dry section and wet section is proposed in this paper as a means to conserving energy and water by combining the benefits of both dry and wet cooling modes. A new thermodynamic coupling characteristics computing model was established to identify the best combination of dry and wet cooling subsystems in the hybrid tower throughout year-round operation based on its air thermodynamic state under the “no plume” principle. A hybrid cooling tower in Inner Mongolia, China, consisting of an elliptical tube heat exchanger with rectangular fins and counter-flow wet packing, was designed as an example under the no plume principle. The minimum number of heat exchanger units in service and the corresponding thermodynamic operating parameters were obtained under a year-round operation. The tower exhibited notable advantages in regards to water conservation compared to the traditional evaporative cooling tower at an estimated yearly savings of 3.74 × 10⁷ kg water.     

轴向单缝偏心药柱爆破效应模型试验研究

为了探究轴向单缝偏心药柱在掏槽爆破中爆炸应力波传播规律和裂纹扩展情况，采用水泥砂浆模型试块开展模型爆破试验，采用超动态应变测试系统对爆炸应力场进行测量。结果表明:在相同爆心距下，背对切缝侧A测点仅为正对切缝侧B测点峰值应力的73.82%；一定角度范围内，峰值应力随偏转角度的增大而减小，偏转角度为0°时峰值应力最大，偏转角度为60°处峰值应力是偏转角度为30°处的74.39%，峰值应力在0°到60°范围内最大衰减达到32.74%；正对切缝方向产生一条贯通炮孔的主裂纹，裂纹发育优于其他方向，且切缝方向没有明显的细小裂纹，这表明轴向单缝偏心药柱具有良好的定向断裂能力。     

两种方法测定地表水总氮结果的探讨

本文使用碱性过硫酸钾消解紫外分光光度法(HJ636-2012)和流动注射-盐酸萘乙二胺分光光度法(HJ668-2013)2种方法对地表水总氮进行对比分析测试,结果显示:流动注射-盐酸萘乙二胺分光光度法测定结果小于碱性过硫酸钾消解紫外分光光度法的测定值。同时对该结果进行了原因分析,为地表水总氮测定方法的选择具有参考价值。     

火源位置对腔室火流动特性影响的实验研究

腔室火流动特性是影响腔室火灾蔓延与通风状况的重要因素。通过一系列小尺度腔室火实验,研究了火源位置变化对腔室火流动特性的影响。实验结果表明,随着火源沿腔室底部从壁面向开口方向移动,在开口中性面以上,同一高度处压差与流速增大,中性面高度和烟气层高度均降低,并导致开口质量流率增大。与火源强度相比,火源位置变化对烟气层高度的影响更为显著。火源位置对中性面高度及烟气层高度的影响在壁面处及开口处更为显著,腔室中部位置变化的影响相对较小。火源由壁面向开口移动,会造成火焰高度降低和水平伸长量增加。基于实验数据,给出了考虑耦合火源位置的腔室内火焰水平伸长量的表达式。研究结果可为相关场景下的腔室火灾理论模型提供实验结果支撑。     

基于叠加-触发原理的铁路危险品运输系统风险场形成机理研究

引入风险场理论研究铁路危险品运输系统风险形成机理，基于系统风险因素识别，建立铁路危险品运输系统风险势函数及对应的风险场强模型，采用触发器原理分析了风险场叠加后的风险形成机理。研究结果表明:内部风险场承受体风险势和风险场强均为代数加和叠加；外部风险场分为单一和多风险源2类，风险势均表现为代数加和叠加，风险场强叠加均满足平行四边形法则。风险状态的变化直接作用于内、外风险场承受体，内部风险场承受体全部或部分崩溃，将导致铁路危险品运输系统失效，其释放的风险场能量将会对外部风险场承受体系统进行攻击，导致外部风险场承受体的部分或整体失效，进而产生风险级联效应。     

固体废物中氰化物的浸出特性研究

采用零顶空提取器,对固体废物中氰化物做浸出试验,浸出液用流动注射法测定,并探讨固体废物中影响氰化物浸出的因素。对浸提时间和浸提次数的试验考察可知,冲刷、溶解、吸附、解吸等多种机制作用于浸出的不同阶段。试验表明,当浸提时间为18 h、浸提次数为2次时能将氰化物基本浸提出来;固体废物经稳固化处理后可明显降低氰化物的浸出量,固体废物本身所含的吸附性组分可不同程度地降低氰化物的浸出量。