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21.
Study of Metal Distribution in Raw and Screened Swine Manure   总被引:1,自引:0,他引:1  
The growth of industrial swine production over the last few years has led to a growth in concern over effluents generated by the activity. Several elements, mainly toxic metals, can be present in swine wastewater and can have a serious environmental impact. It is important, therefore, to know the metal concentration before the discharge of wastewater. In this work the temporal metal distribution in swine manure and its potential reduction using coarse (2 mm) and fine (<0.45 μm) liquid‐solid separation techniques were investigated. In order to do this, different swine manure sample preparation methods for Al, Ba, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr and Zn determination by Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES) were tested. The acid mixtures used to digest the manure sample significantly affected the metal recovery. Good analyte recoveries were observed with nitric acid/hydrogen peroxide mixtures or nitric acid/perchloric acid mixtures. Sulfuric acid/hydrogen peroxide mixtures produced inconsistent results and poor recoveries, mainly for Ba and Pb. It was observed that metal concentrations in swine manure varied greatly with time, up to one order of magnitude, due to changes in swine production such as feed and animal numbers. Metals concentrations observed in the raw wastewater exceeded Brazilian limits for discharge into water bodies and recommendations for agricultural use. Results obtained from the liquid‐solid separation study showed that metals in the raw swine manure were not removed with coarse screening. However, the major fraction of metals were removed by filtration (0.45 μm), with the exception of Na, K and Sr. Thus, the use of liquid‐solid separation techniques that capture the fine solid fractions (and associated metals) from raw manure can have a favorable impact on the environment and contribute to swine production wastewater treatment.  相似文献   
22.
基于主体功能区约束的大气污染物总量控制目标分配研究   总被引:1,自引:0,他引:1  
考虑经济发展水平、污染物排放现状、污染物治理水平、空气质量,特别是国家主体功能区环境目标约束等因素,构建大气污染物排放总量分配的指标体系,用改进的等比例分配方法对2015年国家SO2,NOx总量控制目标进行区域分配。分配结果表明:SO2和NOx削减量大的省份主要集中在华北平原及其周围地区,这些地区污染物排放量大、空气质量较差;削减比例较大的地区主要集中在西部地区以及北京、天津2个直辖市,这些地区单位GDP能耗高、工业污染物去除率低、空气质量差;削减量相对较小的地区主要集中在西南和南部一些省份;削减比例较小的地区主要集中在中南部和南部几个省份,这些地区污染物排放量相对较少,空气质量好于其他省份。  相似文献   
23.
Du  Yao  Ma  Teng  Deng  Yamin  Shen  Shuai  Lu  Zongjie 《Hydrogeology Journal》2018,26(4):1047-1059
Hydrogeology Journal - Quantifying groundwater/surface-water interactions is essential for managing water resources and revealing contaminant fate. There has been little concern on the exchange...  相似文献   
24.
Huang  Yubing  Zhang  Tiantao  Lu  Wei  Wei  Huayong  Liu  Yue  Xiao  Yuchi  Zeng  Zhaonan 《Geotechnical and Geological Engineering》2021,39(7):5213-5227
Geotechnical and Geological Engineering - In order to solve the difficulties of creep deformation of surrounding rock in super large section tunnel, taking Letuan tunnel of Binlai expressway, a...  相似文献   
25.
一种改进的基于非高斯性最大化的预测反褶积算法   总被引:2,自引:1,他引:2  
The predictive deconvolution algorithm (PD), which is based on second-order statistics, assumes that the primaries and the multiples are implicitly orthogonal. However, the seismic data usually do not satisfy this assumption in practice. Since the seismic data (primaries and multiples) have a non-Gaussian distribution, in this paper we present an improved predictive deconvolution algorithm (IPD) by maximizing the non-Gaussianity of the recovered primaries. Applications of the IPD method on synthetic and real seismic datasets show that the proposed method obtains promising results.  相似文献   
26.
梁馨月  曾璐  葛永刚  杜宇琛  曹晓娟 《地质通报》2021,40(12):2061-2070
鲜水河断裂带炉霍-道孚段泥石流沿断裂带呈线性分布,以中高频泥石流为主,过渡型、稀性居多.断裂带内岩体破碎,次级构造发育且活动性强烈使主河床呈阶梯状,为泥石流灾害发育提供了势能转化、物质补给与水力运输条件.研究区泥石流沟(Ksn约140 m0.9)分布在主河陡峭指数高处(Ksn约66 m0.9),且中下游泥石流沟与其入汇...  相似文献   
27.
Sun  Li  Bi  Shuo-ben  Chen  Chang-chun  Zhao  Feng  Lu  Ying 《Natural Hazards》2020,100(3):1105-1116
Natural Hazards - This study involved the systematic collation of historical data from local records, government records, etc., as well as disaster data compiled by contemporary researchers....  相似文献   
28.
为了改进肿瘤的微波热疗,我们进行915MHz微波亚铁磁共振的实验研究。结果表明915MHz微波象2450MHz一样,有明显而尖锐的亚铁共振升温。实验测量了不同聚集状态,不同饱和磁化强度亚铁磁共振介质的共振升温并用鸡蛋清受热固化来显示共振升温度分布的影响。  相似文献   
29.
Particle size analysis for samples from three last glacial cycle loess-palaeosol profiles along a northwestsoutheast transection on the Chinese Loess Plateau has been carried out. The paleoclimatic significance of grain size indices has been obtained by analyzing the fraction content variations and their comparisons with global ice volume and solar radiation variations. The results show that (i) paleoclimatic significance of the grain size indices of loess-palaeosol deposit is different with grain size fraction content and sampling points in Chinese Loess Plateau; (ii) the sub-coarse grain fraction is a good proxy index of East Asia winter monsoon strength and therefore can be used to detect the global climate changes; (iii) the content of sub-fine and fine grain fractions is influenced by both the input of sub-coarse grain fraction and pedogenesis; (iv) the sub-coarse fraction exhibits a negative relationship with the sub-fine and fine fractlon. Project supported by the 9.5 major project of Chinese Academy of Sciences and the open grant of the State Key Laboratory of Loess and Quaternary Geology, Chinese Academy of Sciences.  相似文献   
30.
Wang  ZhenQi  Zhi  DongMing  Zhang  ChangMin  Xue  XinKe  Zhang  ShangFeng  Li  TianMing  Yang  Fei  Liu  LouJun  Cheng  Liang  Lu  Dong  Zhou  FengJuan  Chen  YuanYong 《中国科学:地球科学(英文版)》2010,52(1):106-114

Well che89, located in the Chepaizi area in the northwest margin of Junggar basin, acquires high production industrial oil flow, which is an important breakthrough in the exploration of the south foreland slope area of Junggar basin. The Chepaizi area is near two hydrocarbon generation depressions of Sikeshu and Shawan, which have sets of hydrocarbon source rock of Carboniferous to Jurassic as well as Upper Tertiary. Geological and geochemical parameters are proper for the accumulation of mixed source crude oil. Carbon isotope, group composition and biomarkers of crude oil in Upper Tertiary of well Che89 show that the features of crude oil in Upper Tertiary Shawan Formation are between that of Permian and Jurassic, some of them are similar to these two, and some are of difference, they should be the mixed source of Permian and Jurassic. Geochemical analysis and geological study show that sand extract of Lower Tertiary Wulunguhe Formation has the same source as the crude oil and sand extract of Upper Tertiary Shawan Formation, but they are not charged in the same period. Oil/gas of Wulunguhe Formation is charged before Upper Tertiary sedimentation, and suffered serious biodegradation and oxidation and rinsing, which provide a proof in another aspect that the crude oil of Upper Tertiary Shawan Formation of well Che89 is not from hydrocarbon source rock of Lower Tertiary.

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