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1.
<正> 引言利用双变量氧化物%-二氧化硅%图(Ha-rker,1909)、氧化物%-拉森指数(Larsen,1938)或氧化物%-分异指数(Thornton 和Tuttle,1960)对花岗岩进行了许多主量元素研究,以证明和检验岩石成因假说。数据点的直线性排列或分组曾被解释为同源(descent)的液相线,从而证明了分异趋势的存在,或表明  相似文献   

2.
本文改进了以往用亚甲蓝光度法测定洗涤剂的不足,改用甲基绿光度法测定。改用的方法检出限(3σ)为1.5mg·L~(-1),相对标准偏差小于6%,加标回收率在92.7%-103%范围,方法简便快速。  相似文献   

3.
建立了固相萃取(SPE)-红外分光光度测定水中总油的方法,并对固相萃取条件进行了优化,实验表明,对于1L添加2mg标准油的水样,其总油的回收率为86%-93%,多次重复实验测定的相对标准偏差为2.9%(n=6)。  相似文献   

4.
建立了高效液相色谱与电感耦合等离子体质谱联用技术测定河流底泥中甲基汞的方法。对高效液相色谱和电感耦合等离子体质谱的实验条件进行了优化。在优化条件下,甲基汞的检出限为0.5ng/kg,相对标准偏差为4.7%-9.8%(n=6),加标回收率在84.0%-103.2%之间。该方法灵敏度高,实用性强。  相似文献   

5.
Concentrations of atmospheric PM10 and chemical components (including twenty-one elements, nine ions, organic carbon (OC) and elemental carbon (EC)) were measured at five sites in a heavily industrial region of Shenzhen, China in 2005. Results showed that PM10 concentrations exhibited the highest values at 264 μg/m3 at the site near a harbor with the influence of harbor activities. Sulfur exhibited the highest concentrations (from 2419 to 3995 ng/m3) of all the studied elements, which may be related to the influence of coal used as fuel in this area for industrial plants. This was verified by the high mass percentages of SO42-, which accounted for 34.3%-39.7% of the total ions. NO3-/SO42- ratios varied from 0.64-0.71, which implies coal combustion was predominant compared with vehicle emission. The anion/cation ratios range was close to 0.95, indicating anion deficiency in this region. The harbor site showed the highest OC and EC concentrations, with the influence of emission from vessels. Secondary organic carbon accounted for about 22.6%-38.7% of OC, with the highest percentage occurring at the site adjacent to a coal-fired power plant and wood plant. The mass closure model performed well in this heavily industrial region, with significant correlation obtained between chemically determined and gravimetrically measured PM10 mass. The main constituents of PM10 were found to be organic materials (30.9%-69.5%), followed by secondary inorganic aerosol (7.9%-25.0%), crustal materials (6.7%-13.8%), elemental carbon (3.5%-10.8%), sea salt (2.4%-6.2%) and trace elements (2.0%-4.9%) in this heavily industrialized region. Principal component analysis indicated that the main sources for particulate matter in this industrial region were crustal materials and coal/wood combustion, oil combustion, secondary aerosols, industrial processes and vehicle emission.  相似文献   

6.
建立了顶空/气相色谱-质谱法同时测定固体废物浸出液中35种挥发性卤代烃的方法,系统地研究了顶空条件对测定结果的影响,优化了色谱分离条件。结果表明,各挥发性卤代烃可以实现良好的分离;标准曲线相关系数均大于0.99,检出限为0.6-1.4μg/L,不同浓度的相对标准偏差分别为7.2%-19%,4.3%-15%和4.2%-9.9%,样品加标回收率为71.0%-124%。该方法灵敏度高,具有良好的精密度和准确度,适用于固体废物浸出液中挥发性卤代烃的测定。  相似文献   

7.
<正>2014年8月22日,天津市环保局举行新闻发布会,介绍了天津大气细颗粒物(PM2.5)来源的最新解析结果。天津市环境空气中PM10来源中本地排放占85%-90%,区域传输占10%-15%。在本地污染贡献中,扬尘、燃煤、机动车、工业生产为主要来源,分别占42%、23%、14%、14%,餐饮、汽车修理、畜禽养殖、建筑涂装及海盐粒子等其他排放对PM10的贡献约为7%。  相似文献   

8.
建立了吹扫捕集/气相色谱-质谱法同时测定固体废物浸出液中35种挥发性卤代烃的方法,系统地研究了吹扫捕集条件,优化了色谱分离条件。结果表明,各挥发性卤代烃可以实现良好的分离;标准曲线相关系数均大于0.990,检出限为0.1μg/L-0.3μg/L,不同浓度的相对标准偏差分别为7.6%-16%,2.2%-18%和1.2%-11%,样品加标回收率为73.4%-119%。该方法缩短了分析周期,实现了一次进样多组分同时分析,灵敏度高,具有良好的精密度和准确度,适用于固体废物浸出液中挥发性卤代烃的测定。  相似文献   

9.
建立了微波消解-电感耦舍等离子体质谱(ICP-MS)法,同时测定大气PM_(10)中的钾、钠、钙、镁、铝、硅、铁、锰、铜、锌、铅、镉等12种金属元素的分析方法,样品用HNO_3+H_2O_2经微波系统进行前处理。该法操作简单,酸用量少,罐体封闭,对环境污染小。经多次试验,在确定仪器最佳操作条件后测定。结果表明,方法的检出限在0.4-7.9ng/m~3之间,相对标准偏差为0.5%-6.3%之间,加标回收率在89.1%-108.7%之间,该方法能够快速准确的同时对多种元素测定,检测线性范围宽,测定结果准确可靠,可以用于大气颗粒物中多种金属元素的测定。  相似文献   

10.
采用土壤培养实验,研究添加堆肥和赤泥对土壤中Zn和Cd生物有效性的影响。结果表明,单独添加堆肥或赤泥以及赤泥和堆肥一起添加到土壤,均可以降低土壤中的交换态Cd和Zn含量以及生物有效态Zn和Cd含量。与对照相比,培养1-3个月后,单独添加堆肥、单独添加赤泥和同时添加赤泥与堆肥导致土壤交换态Cd含量分别降低14%-18%、33.3%-46.1%和44.2%-57.7%;土壤交换态Zn含量分别降低54.4%-59%、100%和100%;土壤生物有效态Cd含量分别降低11.8%-14.7%、25.1%-33.7%和32.6%-43.9%;土壤生物有效态Zn含量分别降低14.1%-15.8%、59.7%-72.2%和43.2%-58.4%。  相似文献   

11.
The drainage of peatland areas for peat extraction,agriculture or bioenergy requires affordable,simple and reliable treatment methods that can purify waters rich in particulates and dissolved organic carbon.This work focused on the optimisation of chemical purification process for the direct dosage of solid metal salt coagulants.It investigated process requirements of solid coagulants and the influence of water quality,temperature and process parameters on their performance.This is the first attempt to provide information on specific process requirements of solid coagulants.Three solid inorganic coagulants were evaluated:aluminium sulphate,ferric sulphate and ferric aluminium sulphate.Pre-dissolved aluminium and ferric sulphate were also tested with the objective of identifying the effects of in-line coagulant dissolution on purification performance.It was determined that the pre-dissolution of the coagulants had a significant effect on coagulant performance and process requirements.Highest purification levels achieved by solid coagulants,even at 30% higher dosages,were generally lower(5%-30%) than those achieved by pre-dissolved coagulants.Furthermore,the mixing requirements of coagulants pre-dissolved prior to addition differed substantially from those of solid coagulants.The pH of the water samples being purified had a major influence on coagulant dosage and purification efficiency.Ferric sulphate(70 mg/L) was found to be the best performing solid coagulant achieving the following load removals:suspended solids(59%-88%),total organic carbon(56%-62%),total phosphorus(87%-90%),phosphate phosphorus(85%-92%) and total nitrogen(33%-44%).The results show that the use of solid coagulants is a viable option for the treatment of peatland-derived runoff water if solid coagulant-specific process requirements,such as mixing and settling time,are considered.  相似文献   

12.
AS法制浆废液改性减水剂实验研究   总被引:1,自引:0,他引:1  
通过实验,对AS法麦草、芦苇造纸制浆废液加入Ba(OH)2溶液和吐温-80进行化学改性,制成木素磺酸盐为主要成份的混凝土减水剂,制得的减水剂的3项主要性能指标均达到以国家标准,它们在掺量3‰时净浆减水率为6%-8%,砂浆减水率为15%-16%,掺麦草、芦苇浆废液减水剂的砂浆3d抗压强度分别提高28%和30%,7d抗压强度分别提高18.6和26.4%。  相似文献   

13.
用湿式消解法对淡水鱼的肌肉组织进行消解,处理后用原子荧光光度计测定其砷元素的含量,最低检出质量浓度为0.002mg/kg,测定样品砷含量0.056 mg/kg-0.084 mg/kg,相对标准偏差(RSD)2.21%,回收率93.0%-103%。  相似文献   

14.
长沙市城市固体废弃物处理场渗滤液处理厂采用水质均衡+外置式MBR+NF/RO工艺处理垃圾渗滤液,最终外排清液出水水质达到《生活垃圾填埋场污染控制标准》(GB16889—2008)表2的要求。本文通过统计分析连续稳定运行工况数据,相比一级生化出水,二级生化对COD的去除率提高了16.7%-30%%;氨氮去除率提高了60%-80%;硝酸盐氮去除率在一级生化出水指标的基础上提高了25%-37.5%。通过上述数据,总结出经过二级生化后对相关污染物的深度处理,确保了后续工艺出水稳定达标,也为类似工艺运行项目提供借鉴。  相似文献   

15.
本文采用改进的Ruttenberg萃取方法对黄河下游表层沉积物钙-磷进行分析测定。结果表明:总磷(TP)含量在672.24μg/g1365.37μg/g,其中主要成分为无机磷(IP),平均占TP的比例为95.85%。自生矿和生物所产生的磷灰石和碳酸钙键合磷,岩屑磷灰石和任何其它剩余的无机相磷含量最高,占TP的89.41%-96.11%,探讨了Ca-P对河流和海洋产生的可能影响。  相似文献   

16.
Two plant populations of Phragmites australis and Typha orientalis grown in gravel and sediment substrate were studied to assess their capabilities for purifying polluted water in Taihu Lake, China. The substrate displayed most significant effects on the suspended matter (P < 0.01), with the reduction of 76%-87% and 52%-63% for P. australis, and 83%-86% and 45%-62% for T. orientalis in gravel substrate and sediment substrate, respectively. Both species and substrates significantly decreased the N and P conc...  相似文献   

17.
Sensitivity of green and blue-green algae to methyl tert-butyl ether   总被引:1,自引:0,他引:1  
The toxicity of methyl tert-butyl ether (MTBE) to Chlorella ellipsoidea and Aphanizomenon flos-aquae was tested and assessed for a 15-d incubation with concentrations of MTBE from high (2.00×104 mg/L) to low (2 mg/L). The results showed that the toxicity was low when the concentration of MTBE was in the range 1.00×104-2.00×104 mg/L (the greatest inhibition of growth-rate was 70%-71%, occurred during the day 1-5). Low concentrations (2-500 mg/L) stimulated algal growth up to the greatest effect of 85%-200% w...  相似文献   

18.
A multi-isotope approach and mixing model were combined to identify spatial and seasonal variations of sources,and their proportional contribution to nitrate in the Hutuo River alluvial-pluvial fan region.The results showed that the NO_3~- concentration was significantly higher in the Hutuo River valley plain(178.7 mg/L) region than that in the upper and central pluvial fans of the Hutuo River(82.1 mg/L and 71.0 mg/L,respectively)and in the river(17.0 mg/L).Different land use types had no significant effect on the groundwater nitrate concentration.Based on a multi-isotope approach,we confirmed that the main sources of groundwater nitrate in different land use areas were domestic sewage and manure,followed by soil nitrogen,ammonia fertilizer,nitrate fertilizer and rainwater,and there were no significant spatial or seasonal variations.Combining δ~(15)N-NO_3,δ~(18)O-NO_3~- and δ~(37)Cl results can increase the accuracy of traceability.Nitrification could be the most important nitrogen migration and transformation process,and denitrification did not significantly affected the isotopic composition of the nitrate.The SIAR model outputs revealed that the main nitrate pollution sources in groundwater and river water were domestic sewage and manure,accounting for 55.9%-61.0% and 22.6%(dry season),50.3%-60.4% and 34.1%(transition season),42.7%-47.6% and 35.6%(wet season 2016) and 45.9%-46.7% and 38.4%(wet season 2017),respectively.This work suggests that the random discharge and disposal of domestic sewage and manure should be the first target for control in order to prevent further nitrate contamination of the water environment.  相似文献   

19.
为了持续改善环境空气质量,判断PM_(2.5)的来源是控制和治理的关键。该文应用WRF-CAMx模式,对福州地区2013年1、4、7、10月污染物的传输过程进行模拟。结果显示,工业源对PM_(2.5)浓度的贡献率最大,为45.9%~62.3%,其次交通源为17.2%~26.7%,民用源为13.6%~17.7%;本地源排放是福州地区污染物主要来源,本地源对PM_(2.5)的贡献率为83.8%~89.1%,外界传输贡献率为10.9%~16.2%;福州地区一次PM对PM_(2.5)的贡献最大,贡献率为64.6%~82.9%,SO2的贡献率为9.1%~12.1%,NOx贡献率为0.5%-12.5%。  相似文献   

20.
取大辽河人海口柱状沉积物,通过寡核苷酸荧光探针原位杂交(FISH)方法分析了沉积物中微生物数量及种群的垂直分布特征,并考察了沉积物理化特性对微生物丰度的影响.结果表明,用5-(4,6-二氯三嗪基)氨基荧光素(简称DTAF)染料染色及EUB338探针杂交检测出的微生物细胞总数及细菌数量随沉积物深度呈现相同变化趋势.在沉积物表层(0-5cm)和中间层(23.5-29.5 cm)数量相对较高.细胞总数为7.9×108-20.1×108cell·cm-3,细菌数量为5.1×108-14.4×108个·cm-3,细菌检出率平均值为75.4%.用ALF1b、BET42a和GAM42a探针检测出α-、β和γ-变形杆菌在柱状沉积物中的普遍存在,α-、β和γ-变形杆菌检出量占细胞总数的25.O%-65.6%,其中以γ-变形杆菌为优势菌,其检出率为9.8%-40.8%.用ARCH915探针检测出的古细菌数量占细胞总量的1.0%-11.8%.总体看来,沉积物中微生物数量与沉积物的粘土含量呈正相关,在一定程度上受总有机碳影响,但与汞含量关系不明显.  相似文献   

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