透水混凝土路面对径流水量削减试验

透水混凝土路面作为低影响开发技术之一,对雨洪的管理与控制具有重要作用。对透水混凝土路面对径流的控制作用进行试验,结果表明:基于设计路面和北京降雨参数,降雨历时分别为30,60,120 min时,透水混凝土路面对径流总量的削减率分别达到60%、55%和40%以上,对洪峰流量的削减率分别达到65%、63%和40%以上;降雨重现期从1年增到100年,产流延迟时间从13 min降至5 min。试验表明,透水混凝土路面的雨量径流系数在0.18~0.54,远小于普通混凝土路面的雨量径流系数0.91。结果表明,透水混凝土路面对延迟产流时间、削减径流水量、削减洪峰流量以及降低径流系数具有很好的作用,可以为该低影响开发技术在国内的应用设计提供参考。     

海河流域水质变化与水量的关系研究

采用曼-肯德尔和森方法,对海河流域省界断面水质达标比例和主要指标的超标比例及降雨量进行分析,探讨水质的演变特征及与降雨量的关系.结果表明:近10年非汛期达标比例和全年期COD超标比例呈现显著的变化趋势.氨氮的断面超标比例较高.汛期水质达标比例与汛期降雨量存在显著负相关,汛期降雨量增加降低了水质达标比例.DO、高锰酸盐指数、BOD和氨氮的超标比例年内变化存在差异,其主要与指标自身特性、气温以及与水文循环有关.     

AERMOD模式应用于集中供热削减污染面源参数选取探讨

本文根据阳高县城2012年、2013年采暖季SO2、NO2监测浓度,结合2013年集中供热所替代土小采暖炉灶减排的污染物排放量,采用AERMOD模式进行预测验证,并对模式参数取值进行了探讨,以期对模型的同类型应用提供参考。     

Gasification of Inferior Coal with High Ash Content under CO2 and O2/H2O Atmospheres

The gasification reaction of Nantong inferior coal was investigated in a laboratory fixed-bed reactor under CO₂ and O₂/H₂O atmospheres. The effects of the bed temperature and inlet-gas concentration on the yields of CO, H₂, and CH₄ were studied. The effects of coal ash and particle size on the fixed-carbon conversion were also investigated, and kinetic analysis was conducted with a homogeneous model. The product-gas-heating value and fixed-carbon conversion increased when the temperature was increased from 950 °C to 1100 °C under CO₂ atmosphere. When the inlet-CO₂ concentration was increased from 50 to 100 vol.%, the low heating value of the product gas and carbon conversion ratio slightly increased. During the gasification of inferior coal under the O₂/H₂O atmosphere, the CO concentration increased rapidly with increasing temperature. The H₂ and CH₄ concentrations increased initially and then decreased. The maximum gas heating value of 7934 kJ/m³ was obtained under the O₂ concentration of 70 vol.% at a bed temperature of 1050 °C. The cold-gas efficiency increased with increasing temperature and became 40.6% and 86.4% at 1100 °C under the CO₂ and O₂/H₂O atmospheres, respectively. The gasification reaction of the Nantong inferior coal strongly depended on the content of inherent inorganic matter. The gasification rates for both the CO₂ and O₂/H₂O atmospheres were independent of the particle size. The activation energy for the CO₂ and O₂/H₂O gasification reactions were 137 and 81 kJ/mol, respectively. The gasification reactions of the Nantong coal, which was performed under two different atmospheres, were compared and the reaction activity of the gasification reaction under CO₂ atmosphere was found to be much lower than that under the O₂/H₂O atmosphere.     

The study of wintertime heat preservation measures constructed wetland in northern China subsurface flow

人工湿地作为一种造价较省,运行成本低的污水处理技术,目前已经得到了广泛的应用.但是在北方地区,人工湿地受到冬季气候影响,无法正常运行,降低了它的使用效率.试验针对北方冬季低温环境下,人工湿地无法正常运行的问题,对3种不同的保温措施进行历时两年的对比试验,通过对TP、TN、NH4＋-N和COD等4种主要污染物和人工湿地出水水温的跟踪监测,检验了不同保温措施的效果.试验结果表明：在冬季,使用薄膜法保温措施的处理系统中,COD、TN和NH4＋-N的去除率分别为30%～45%、40%～60%和35%～60%,比温棚法和冰封法的出水中污染物去除率高10%～20%.TP在出水中含量波动较大,去除率为19%～70%,伴有磷释放现象,但是在薄膜保温下TP的去除效果也要好于温棚和冰封.经过SPSS16.0分析,薄膜保温的人工湿地出水水质与冰封和温棚法相比具有显著性差异.在对人工湿地曝气槽和出水口的污水水温进行监测发现,利用薄膜保温的人工湿地出水口水温高于冰封和温棚的水温,进一步证明薄膜保温可以有效提高人工湿地内的温度,为人工湿地正常运行提供了保证.而且薄膜保温措施的操作简便、造价低,适合推广应用.     

基于AWTP指数的浙江省干旱规律时空分析

利用浙江省51个气象站1960-2009年的50 a逐日降水资料,基于降水的平均等待时间(AWTP)指数,采用小波分析和克里金空间插值方法对浙江省干旱时空特性进行分析。结果表明,浙江省的干旱随时间增加有加剧趋势。在50 a中,1979年干旱程度最强,相当干期值最大,达到52 d。在趋势变化上还同时叠加着明显的年际和年代际变化。浙江省干旱存在3 a左右的主周期;另外浙江省的干旱具有明显的区域性,干旱程度由南向北递增。嘉兴的平湖市及浙西金华周围内陆丘陵盆地发生干旱比其他地区更明显,其次是杭州市西部、温州市及台州市温岭等东南沿海山地丘陵地区,中东部的宁波市和绍兴市、西北部的湖州市以及浙江西南部等地区发生干旱程度较轻。     

近20年江苏省气温和降水资源变化对稻麦生产的影响

利用数理统计及非线性回归模型等方法,探求江苏省近20 a气温和降水资源变化对稻麦生产的影响。结果表明:近20 a平均温度(Tavg)、最高温度(Tmax)和最低温度(Tmin)年增加趋势为0.050℃、0.056℃和0.061℃,降水量(Prec)变化不明显。在近年气候变暖下,冬小麦全生育期和营养生长期呈显著缩短趋势(p<0.05),分别年缩短0.41 d和0.70 d,而生殖生长期年显著延长0.32d(p<0.05)。冬小麦营养生长期和全生育期长短与该时段Tavg、Tmax和Tmin呈显著负相关(p<0.05)。水稻生育期长短变化不大,呈现整体向后推移趋势。2000s与1990s相比,冬小麦生育期缩短,而冬小麦和水稻播期均推迟,因此麦-稻换茬时间延长5 d,稻-麦换茬时间减少3 d。近20 a稻麦产量均呈增加趋势,稻麦周年产量每年极显著增加85.5 kg/hm²(p<0.01)。利用非线性模型分析表明,Tavg、Tmax和Tmin每增加1℃稻麦周年单产分别增产0.47%、0.10%和1.92%,主要是因为冬小麦产量增加幅度大于水稻减产幅度。为合理利用气候资源,可考虑推迟冬小麦播种,防止其冬前旺长。选育晚熟耐高温水稻品种,促进水稻生殖生长,提高产量。     

Magnetic molecularly imprinted polymer prepared by microwave heating for confirmatory determination of chloramphenicol in chicken feed using high-performance liquid chromatography-tandem mass spectrometry

Abstract

A magnetic molecularly imprinted polymer (MMIP) for chloramphenicol was prepared using a surface-imprinted and microwave-heating-induced polymerization method. The surfaces of the magnetic particles were first double-bond functionalized with 3-(trimethoxysilyl)propyl methacrylate (γ-MPS), followed by the copolymerization of 4-vinyl pyridine (4-VP) and trimethylolpropane trimethacrylate (TRIM) in the presence of chloramphenicol as a template and 1,1-azobis(cyclohexane-carbonitrile) (ABCN) as an initiator in a mixture of dimethyl sulfoxide and water with microwave heating at 80°C. The magnetic polymer possesses supraparamagnetic properties and was used to concentrate and cleanup chicken feed extract, followed by chromatographic separation using a Lichrospher®100 RP C8 column and detection with two multi-reaction monitoring transitions at m/z 321→ 152 and m/z 321→ 257. The mean recoveries obtained at two spiking levels were in the range of 94.6–100% The relative intra- and inter-day standard deviations were in the range of 1.4–2.6% and 5.1–5.7%, respectively. The detection limit of the method was 0.12 µg kg^?1. This confirmatory method was successfully applied to determine chloramphenicol in chicken feed samples.     

Reproductive trade-offs from mating with a successful male: the case of the tephritid fly Anastrepha obliqua

In lekking species, females may become sperm-limited when mating with sexually successful males, and this may be exacerbated by a poor male diet. Polygynous males may also be limited by the amount of accessory gland products (AGPs) they can transmit to females, which in turn may influence the females’ refractory period and longevity. Here, we tested the effect of male mating history, larval and adult diet on copula duration, mating intervals, female fecundity, fertilisation success, life span and likelihood to remate using sexually successful males of the lekking tephritid fly Anastrepha obliqua. Flies originated from either a native or exotic host fruit and were protein-fed or deprived. Male diet and larval host influenced copula duration, while the time elapsed between matings was affected by the interaction of mating order and male adult diet. Female fecundity was not influenced by female position in mating order or protein inclusion into the male diet. However, mating order and male larval diet influenced female fertilisation success. Importantly, as males mated successively they were less able to induce a refractory period on females, as the last females to mate with a male were more likely to remate and had slightly longer life spans than the first females to mate with males. These results might be attributed to a decrease in male AGPs with increasing male mating frequency. We discuss the role of conditional expression of male mating frequency with respect to A. obliqua’s life history, the trade-off that females face when mating with a successful male, the effect of larval diet on adult sexual performance and the possibility for sexual conflict to occur due to high male mating rates and fitness costs to females.     

西安南郊采暖期大气颗粒物PM_（2.5）的污染特征分析

为研究西安市南郊地区采暖期大气颗粒物PM2.5的污染浓度及水溶性成分,使用颗粒物采样器于2009年1月6日-2009年2月15日进行PM2.5采样。将24 h分为8个阶段,每天3 h定时采样。结果表明,西安市南郊地区采暖期PM2.5明显污染,24 h中PM2.5污染状况最严重的时段为21：00-23：59;PM2.5中NH4^＋、NO3^-和SO42^-是其最主要的水溶性组分,在PM2.5中的平均质量混合比分别为10.225%、13.698%和15.650%,三者在PM2.5中质量混合比最高的时段分别为06：00-08：59、03：00-05：59和18：00-20：59。