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1.
水中竞争性阴离子对Fe0除砷效率的影响研究   总被引:5,自引:0,他引:5  
本文研究水中几种无机阴离子H2PO3^-、SiO3^3-、NO3^-、SO4^2-、HCO3^-对零价铁(Fe^0)除砷效率的影响,实验结果显示:H2PO3^-、SiO3^3-的存在会由于竞争性吸附显著降低Fe^0的除砷效率,而高浓度的NO3^-与SO4^2-可以促进Fe^0对砷的去除,HCO3^-对Fe^0的除砷效率影响不大.  相似文献   

2.
等离子色谱法测定矿泉水中F^—,Cl^—,NO3^—,SO4^2—   总被引:1,自引:0,他引:1  
郭岩 《汕头科技》2001,(2):62-63
本文应用离子色谱法测定了矿泉水、纯净水中F^-,Cl^-,NO3^-,SO4^2-等阴离子,结果表明,利用该法测定以上阴离子,速度快,方法简便,能一次同时测定多种离子,获得准确可靠的定性和定量结果。  相似文献   

3.
论述离子色谱分析条件优选的数学模型及其在分析近地下水模拟样品中的应用问题。求解由指数函数和对数函数构成的特征方程可知,由等浓度的Na2CO和NaHCO3组成的淋洗液,最佳量浓度为0.00385mol.L^-1。当使用8053A分离柱,最佳量浓度流动相流速为2mL.min^-1时,样品中七种阴离子(F^-、CL^-、NO2^-、PO4^3-、SO3^2-及SO4^2-)的背景抑制电导波峰分辩率均可达到1.50以上。  相似文献   

4.
重庆缙云山降水化学组成的季节变化特征分析   总被引:2,自引:1,他引:2  
对重庆缙云山自然保护区1998-1999年126个降水雨样的主要化学组成成分特征和季节变化特点进行了分析研究,结果表明,缙云山降水pH平均值为5.23,电导率为33.90μs/cm,降水的酸化与污染程度低于重庆市市区,降水pH值和各主要离子表现出明显的季节变化特征,总体表现为冬、春季污染程度高于夏秋季,这可能与降水量的季节分布等有关,降水中NH4^-和Ca^2+的大量存在极大地中和了酸根离子(SO4^-、NO3^-、Cl^-)对雨水的酸化作用,提高了降水pH,降低了酸雨发生频率,降水pH与各主要离子在冬季表现出显著的负相关关系,碱性阳离子(K^+、Na^+、Ca^2+、Mg^2+、NH4^-)与SO4^2-的相关性在冬季极为显著,在夏季则较弱,电导率与SO4^2-的相关性表现出同样的季节变化特点。  相似文献   

5.
研究了不同浓度的NaCl、MgCl2、AlCl3、NaNO3、Na2SO4和NaBr等电解质对解脂假丝酵母吸附铬的盐效应.吸附动力学表明,阴离子相同时,低浓度的Na^+、Mg^2+对吸附有促进作用,而Al^3+在实验设定的浓度范围内对吸附均有抑制作用,盐效应顺序为Al^3+〉Mg^2+〉Na^+.阳离子相同时,低浓度的α—对吸附有促进作用,而Br^-、NO3^-、SO4^2-对吸附均有抑制作用,盐效应顺序为Br^-〉NO3^-〉SO4^2-〉Cl^-.生物吸附过程的盐效应可能与阳离子的半径以及与配位体所形成的配合物的稳定性有关,也可能与菌体表面带正电荷的官能团与阴离子之间的静电作用有关。  相似文献   

6.
于2009年10月至2010年8月间采集郑州市大气颗粒物PM2.5与PM10样品,对其质量浓度及水溶性离子进行分析研究.结果表明:PM2.5在秋、冬、春、夏四季的质量浓度的平均值分别为134.9、121.6、77.9和102.0μg/m^3,PM10在秋、冬、春、夏四季的质量浓度的平均值分别为193.2、184.0、140.9和140.5μg/m^3,日均值超标率分别达77.8%和59%.PM2.5和PM10质量浓度呈现很好的相关性,春季粗粒子在PM10中的比例相对较高,而秋、冬和夏季细粒子是PM10的主要组成部分.主要的水溶性离子是SO4^2-、NO3^-和NH4^+,大部分以(NH4)2SO4和NH4NO3形式存在;NO3^-和SO4^2-质量比小于1,说明采样期间郑州市大气以固定排放源污染为主.  相似文献   

7.
广州市酸雨状况及其化学组成对比分析   总被引:3,自引:0,他引:3  
1993年~2006年广州市降水监测结果表明,广州市降水pH年均值范围为4.31~4.78,酸雨频率70.2%~82.0%。降水中化学组分以SO4^2-、NO3^-为主要阴离子,Ca^2+、NH4^+为主要阳离子,酸雨类型转变为硫酸型和硝酸型并重。广州市酸雨污染状况依然严重。  相似文献   

8.
离子色谱法同时测定饮用水中7种阴离子研究   总被引:2,自引:0,他引:2  
研究化学抑制电导-离子色谱法同时测定饮用水中7种阴离子的分析方法.将水样经0.45μm微孔滤膜过滤,经过RP柱处理后连续进样,利用离子色谱仪ICS-3000同时测定F^-、Cl^-、NO2^-、Br^-、NO3^-、SO4^2-、PO4^3- 7种阴离子的浓度.试验采用IonPac AS11A分离拄和IonPac AG11A保护柱,淋洗液由淋洗液自动发生器产生,流速为1.2mL/min.保留时间的RSD为0.06%~0.59%,峰面积的RSD为1.06%~2.36%,各离子加标回收率为87.6%~105.7%,标准曲线的相关系数为0.9959~0.9998.该方法具有灵敏、准确、简便等优点,可用于饮用水中7中阴离子的同时分析.  相似文献   

9.
离子色谱法测定矿泉水中F^-、Cl^-等阴离子   总被引:1,自引:0,他引:1  
建立了矿泉水中F^-、Cl^-,NO3^-、SO4^2-四种阴离子的离子色谱测定方法.方法采用ICS-1000型离子色谱仪.Lonpac AS14A色谱柱,ASRS ULTRA Ⅱ抑制器,8.0mmol·L^-1碳酸钠-1.0mmol·L^-1碳酸氢钠混合液为淋洗液,流速为1.0mL·min^-1.方法的线性范围广、线性相关性好(r=0.9992—0.9999),相对标准差(RSD)为0.28%~0.91%,平均加标回收率为98.97%-103.4%,最低检测限为0.0111-0.0522mg·L^-1.该法测定矿泉水中F^-、Cl^-、NO3^-、SO4^2-等阴离子,不需外加试剂对抑制器进行再生.具有操作简便、灵敏度高、准确、快速等优点.  相似文献   

10.
离子交换树脂分离测定硒中硫   总被引:2,自引:0,他引:2  
研究了硒中硫的分离方法,利用阴离子交换树脂分离SeO3^2和SO4^2-,研究了分离条件,采用二苯卡巴肼分光光度法测定SO4^2-。加标回收率97%-104%。方法用于粗硒,亚硒酸钠中硫的分离测定,结果满意。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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