基于井口涌水量变化类型判断岩溶含水层厚度

针对含水相对均匀的溶洞-裂隙水含水岩组,为判断岩溶含水层厚度,通过对空气潜孔锤钻进工艺施工钻孔井口涌水量变化进行分析,结果发现:利用该工艺施工的钻孔井口涌水量一般会出现稳定型、降低型和增长型三种变化类型;井口涌水量变化类型反映了岩溶含水层是空间尺度上发育的垂向地下水系统,具有分层特征,其厚度与碳酸盐岩岩溶化程度的不均一性耦合,体现了碳酸盐岩岩体内不同空隙的发育规模、密度及其相互间的联系程度;明确了地下水埋深状况以及含水层的构成条件。故采用空气潜孔锤钻进工艺施工的钻孔,在非干孔情形下,可以利用井口涌水量的变化类型判断岩溶含水层厚度。     

微波在废树脂中的穿透厚度研究

通过对不同功率微波在不同规格钢桶中对不同含水率的树脂中的穿透厚度的研究可知,微波在树脂中的穿透厚度主要与树脂自身含水率有关,与钢桶的规格尺寸也有一定的关系,而微波功率的影响则可基本忽略不计;对于含水率50％左右的树脂,微波在12L钢桶中的穿透厚度是130 mm;在200L钢桶中的穿透厚度是70mm.该研究成果对微波干燥工艺的具体参数的选取和扩大规模台架装置的设计研究等有重要意义.     

城市土地利用类型与PM2.5浓度相关性研究——以武汉市为例

随着我国工业化的不断发展,在我国的主要经济发展地区的雾霾天气不断爆发,使我国的大气环境日益恶化,严重影响了人们的日常生活和身体健康。PM2.5作为雾霾的重要组成成分,也日渐成为环境领域的研究热点问题。随着全球性变化研究领域逐渐加强了对土地利用与生态环境的相关研究,因此无论从法律和社会经济发展的角度,还是从生态资源保护与环境可持续发展的角度,土地利用与PM2.5的相关研究都显得相当重要。研究目的:分析武汉市各类用地类型与PM2.5浓度的相关性程度。研究方法:使用ENVI与ArcGIS对武汉市2013年MODIS气溶胶产品进行空间分析与插值处理,再应用SPSS将其与武汉市2013年10个观测点的PM2.5浓度数据作相关性分析,以证实MODIS气溶胶厚度与PM2.5浓度的相关性,并建立两者的线性回归方程,然后利用计算后的武汉市整体PM2.5浓度分布与各土地利用类型进行相关性研究。研究结果:武汉市PM2.5浓度有明显的空间分布特征,绿化面积比例与PM2.5浓度呈显著负相关,建设用地面积比例与PM2.5浓度呈显著正相关,未利用地面积比例虽然与PM2.5浓度呈正相关,但相关性较低,而耕地与水体对PM2.5浓度没有显著影响。研究结论:土地利用类型对武汉市PM2.5浓度的分布有显著的影响,其与搭载MODIS传感器的遥感卫星监测方式的结合能成为研究大范围特定区域PM2.5浓度空间格局的新方法,并且增加城市绿化面积,控制建设用地规模能有效减少PM2.5浓度。     

滁州地区覆盖层厚度对场地地震动参数的影响

以滁州地区近百个钻孔资料为原型建立土层模型,采用一维频域等效线性化波动方法进行了土层地震反应分析,重点分析了覆盖层厚度对场地地震动参数的影响。研究结果表明,随着覆盖层厚度的增加,地表峰值加速度及土层放大系数逐渐增大,当覆盖层厚度超过一定值时,地表峰值加速度及土层放大系数呈逐渐缓慢减小的趋势;而反应谱特征周期总体上随着覆盖层厚度的增加而逐渐增大。     

Influence of sewage culvert cover plate thickness on dynamic response and damage of the cover plate under gas explosion

In order to address the risk of combustible gas explosions in sewage culverts, a numerical model was established using ANSYS/LS-DYNA software. The model consisted of a culvert and a cover plate, and was used to study the effect of cover plate thickness (ranging from 0.08 m to 0.12 m) on the dynamic response and damage of the structure under explosive loads. The results indicated that, during the loading negative pressure stage, the equivalent stress peak value of the central monitoring unit of the cover plate first increased and then decreased with increasing cover plate thickness. Additionally, the maximum principal stress peak value first decreased and then increased, while the maximum shear stress peak value first increased and then decreased. During the loading positive pressure stage, the maximum principal strain peak value of the monitoring unit decreased overall with increasing cover plate thickness. However, the equivalent plastic strain peak value initially increased and then decreased gradually. The equivalent strain indicated that plastic damage occurred in the cover plate. Beyond a thickness of 0.11 m, increasing the cover thickness did not appear to enhance its resistance to plastic damage. The damage analysis revealed that as cover plate thickness increased, the peak displacement and velocity of the monitoring unit continued to decrease, while the overall stability and explosive resistance of the cover plate increased. Additionally, the number of damaged fragments decreased. However, once the cover plate thickness reached 0.11 m, the bonding performance of the reinforced concrete structure had been fully developed, increasing the thickness of the cover plate no longer had a significant impact on the explosive resistance of the cover plate.     

焙烧炉筒体结构强度有限元分析

对焙烧炉筒体结构进行有限元建模仿真,考虑热应力、压力和重力对筒体结构受力的影响,计算了焙烧炉关键部位的蠕变疲劳寿命,同时探究进气温度、保温层及对流系数等参数的影响。结果表明:热应力是影响结构强度的关键因素;焙烧炉筒体在许用蠕变变形量为5%的情况下,其使用寿命超过设计寿命;在筒体加热过渡段铺设保温层,降低与外界空气对流和提高进气温度,有利于降低筒体应力。     

城区与郊区PM2.5污染及传输特征差异性

基于云高仪激光雷达、飞机AMDAR数据和常规站点等多源观测数据,并与数值模拟（CAMx-PSAT模型）相结合,以京津冀典型城市——北京城区与郊区（密云）和石家庄城区与郊区（平山）为案例研究区域,对城区和郊区边界层高度差异（ΔPBLH）、地面PM_2.5浓度差异（ΔSurf_PM_2.5）、高空PM_2.5浓度差异（ΔVert_PM_2.5）和传输通量强度及高度分布特征差异进行分析.结果表明,由于人为热源、短波辐射和热力湍流等因素,导致城区年均边界层高度（PBLH）较郊区高8%~29%,且不同季节下城区PBLH月均较郊区高2%（石家庄4月）~47%（北京7月）.由于人为排放、逆温和大气湍流等共同作用,在0~1260 m之间等高度城区年均ρ（PM_2.5）较郊区高0.1（石家庄）~29.7（北京）μg ·m^-3,随高度增加而减小.城区年均总净通量强度远大于郊区,城区表现为流出,郊区表现为流入,是由于城区低压和郊区高压,形成城郊热力环流.北京城区和郊区与周边的年均总净通量强度之和（44.77 t ·d^-1）大于石家庄（34.44 t ·d^-1）.受风速和PM_2.5浓度的影响,在0~1260 m之间,城区和郊区与周边的净通量随离地高度的增加通量强度呈现明显增大趋势,其中1月城区和4月郊区与周边的传输交换对环境影响最为明显.不同季节下城区和郊区最大净通量的强度差异明显,两者相差2.23~4.48倍;但最大净通量强度的高度特征差异较小,主要位于611~1260 m.     

气浮过滤法处理印染废水

高效气浮工艺是处理印染废水的有效方法，通过在溶气罐中使用高效填料、优化设计溶气释放器及使用双层快滤，可大大提高处理效果。     

Enrichment and Isolation of a Mixed Bacterial Culture for Complete Mineralization of Endosulfan

In the present study, we isolated three novel bacterial species, namely, Staphylococcus sp., Bacillus circulans–I, and Bacillus circulans–II, from contaminated soil collected from the premises of a pesticide manufacturing industry. Batch experiments were conducted using both mixed and pure cultures to assess their potential for the degradation of aqueous endosulfan in aerobic and facultative anaerobic condition. The influence of supplementary carbon (dextrose) source on endosulfan degradation was also examined. After four weeks of incubation, mixed bacterial culture was able to degrade 71.82 ± 0.2% and 76.04 ± 0.2% of endosulfan in aerobic and facultative anaerobic conditions, respectively, with an initial endosulfan concentration of 50 mg l^?1. Addition of dextrose to the system amplified the endosulfan degradation efficiency by 13.36 ± 0.6% in aerobic system and 12.33 ± 0.6% in facultative anaerobic system. Pure culture studies were carried out to quantify the degradation potential of these individual species. Among the three species, Staphylococcus sp. utilized more beta endosulfan compared to alpha endosulfan in facultative anaerobic system, whereas Bacillus circulans–I and Bacillus circulans–II utilized more alpha endosulfan compared to beta endosulfan in aerobic system. In any of these degradation studies no known intermediate metabolites of endosulfan were observed.     

Review of advances in the thin layer chromatography of pesticides: 2004–2006

Applications of thin layer chromatography and high performance thin layer chromatography for the separation, detection, and qualitative and quantitative determination of pesticides, other agrochemicals, and related compounds are reviewed for the period from July 1, 2004 to November 1, 2006. Analyses are covered for a variety of samples, such as food, crops, biological, environmental, pharmaceuticals, and formulations, and for residues of pesticides of various types, including insecticides, herbicides, and fungicides, belonging to different chemical classes. In addition to references on residue analysis, studies such as pesticide-structure relationships, metabolism, degradation, and lipophilicity are covered, many of which make use of thin layer radiochromatography.