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1.
pH对油酸钠在钛铁矿与钛辉石表面吸附的影响   总被引:2,自引:0,他引:2  
通过热力学计算、X线光电子能谱及红外光谱测试,研究pH对油酸钠在钛铁矿与钛辉石表面吸附的影响。研究结果表明:钛铁矿在pH>5.5时都保持了较好的可浮性,钛辉石在pH为6~9和pH>10的条件下具有一定的可浮性;在酸性条件下,钛铁矿表面的Fe3+,Ca2+,Mg2+和Ti4+以及钛辉石表面的Fe3+,Ca2+,Mg2+和Al3+均能与油酸钠发生化学作用,其中钛铁矿表面的Fe2+在浮选过程中可以被氧化为Fe3+,成为矿物表面主要的活性吸附点,继而油酸根离子取代羟基生成油酸铁而吸附于矿物表面;钛辉石表面则以Ca2+和Mg2+与油酸根的化学作用为主。在碱性条件下,钛铁矿与钛辉石表面均主要以Ca2+和Mg2+为主与油酸钠作用。  相似文献   

2.
采用化学分析方法探索了盐湖环境的Na+,K+,Mg2 +,SO42 - 和Cl- 离子在混凝土和钢筋混凝土结构中的扩散规律 ,并用XRD ,DTA TG和SEM EDAX方法研究了侵蚀性离子与混凝土之间的相互作用机理 .结果表明 ,Mg2 +和SO42 - 离子在混凝土中呈现出不同的分布规律 ,Na+,K+和Cl- 离子的扩散速度大小顺序为 :VCl- >VNa+ ≈VK+ .盐湖侵蚀性离子渗入混凝土后 ,一部分吸附于孔隙内表面 ,结晶成食盐NaCl和光卤石KCl·MgCl2 ·6H2 O ;另一部分与水化产物发生化学腐蚀 ,形成石膏CaSO4·2H2 O ,南极石CaCl2 ·6H2 O和氢氧化镁Mg(OH) 2 ;还有一部分与CSH凝胶发生 3种相互作用 :吸附于凝胶粒子表面 ,进入凝胶结构形成含水硅酸钙镁 (C1 -xMx) 1 .1 5- 1 .70 SH(x =0 .2 2~ 0 .39)和碱硅凝胶 (C1 -xNx) 1 .85- 1 .60SH(x=0 .39~ 0 .63) .  相似文献   

3.
铝电解中的电极过程——Ⅰ.阳极过程   总被引:1,自引:0,他引:1  
研究了铝电解中的阳极反应、阳极过电压、电解质对炭电极的湿润性、双电层电容、交流阻抗、阳极效应等阳极过程,得出了可以相互证明的结论·①在阳极区可发生5个电化学反应,阳极产物分别是CO,CO2,COF2,CF4和F2;②在电流密度为002~12A/cm2范围内符合Tafel方程·反应控制步骤为化学反应CxO·O分解反应的迟滞,反应级数为05级;③测量了冰晶石氧化铝熔体在石墨电极上的湿润性和双电层电容·发现在10V左右,湿润角有一最大值,双电层电容有一最小值,因此认为此电位为零电荷电位;④提出了发生阳极效应的新机理·认为当电解质中Al2O3...  相似文献   

4.
采用高温固相法合成了Ga8Mg(SiO4)4Cl2:Dy3+和Ca8Mg(SiO4)4Cl2:Eu2+,De3+荧光粉.Dy3+激发的Ca8Mg(SiO4)4Cl2荧光粉发射光谱在蓝光区和黄光区有两个发射带,分别对应4F9/2→6H15/2和4F9/2→6H13/2的跃迁发射,蓝光和黄光混合成白光,通过Dy3+浓度改变可以调节白光的色温和色坐标.Eu2+,Dy3+共激发Ca8Mg(SiO4)4Cl2的发光强度明显比单掺Eu2+荧光粉的高,这是由于Dy3+→Eu2+之间存在共振能量传递.  相似文献   

5.
乌鲁木齐城市表层土壤盐分特征分析   总被引:1,自引:0,他引:1  
以乌鲁木齐城市表层土壤为研究对象,对建成区和郊区不同用地类型土壤全盐量、可溶性离子等指标进行测定,采用相关性分析以及主成分分析方法分析土壤盐分特征.结果表明:在研究区,郊区未利用地、郊区农用地、建成区土壤全盐量均值依次增高.不同土壤类型全盐量变异系数范围为0.691~0.715,属于强变异强度,离散程度较大.Cl-,Na+,Ca2+,SO2-4含量较高,尤其是SO2-4;在0.01水平上,土壤全盐与Cl-,SO2-4,Ca2+,Mg2+,Na+呈显著正相关,与HCO-3呈显著负相关;通过主成分分析可以看出,Mg2+,SO2-4,Ca2+3个离子是表征研究区土壤盐渍化的主要特征因子,经土壤盐渍化程度的等级划分标准评价,确定研究区土壤为非盐渍化土.  相似文献   

6.
采用高温固相法制备了Sr3Al2O6:Eu2+, Dy3+红色长余辉发光材料,研究了H3BO3掺杂量对其性能的影响.利用X射线衍射仪对材料的物相进行了分析,结果表明,1 200℃下制备的不同H3BO3掺杂量样品的物相为Sr3Al2O6 ;采用荧光分光光度计、照度计测定了样品的发光特性,结果表明Sr3Al2O6:Eu2+,Dy3+的激发峰位于472 nm的宽带谱,发射峰为位于612 nm的宽带谱,对应于Eu2+的4f65d1→4f7的跃迁;H3BO3的加入在促进产物晶化的同时,还可改变进入晶格中的Eu、Dy离子的浓度,从而改善余辉特性.余辉测试表明,Sr2.95Al1.8O6:0.02Eu2+,0.03Dy3+,0.2B3+的余辉时间最长,可达620 s(≥1 mcd/m2).  相似文献   

7.
Ca2+对钛铁矿与钛辉石浮选行为的影响   总被引:1,自引:0,他引:1  
以油酸钠为捕收剂,研究钛铁矿与钛辉石表面离子的溶出行为,并考察加入与脱除Ca2+对钛铁矿和钛辉石浮选行为的影响.研究结果表明:在浮选体系中加入Ca2+,对钛铁矿的浮选影响不大,但在碱性条件下活化了钛辉石的浮选;在浮选过程中,钛铁矿与钛辉石表面均有大量Ca2+溶解于矿浆中;脱除溶解离子后,钛铁矿的可浮性在弱酸性pH区间变化不大,在碱性pH区间明显变差,钛辉石在整个pH区间可浮性均变差;在脱除溶解离子后的矿浆体系中加入Ca2+,2种矿物在碱性矿浆环境下的可浮性都有所恢复;在碱性条件下,呈羧基络合物和氢氧化物沉淀形式存在的Ca2+吸附在钛辉石表面,使钛辉石表面油酸根离子的吸附活性质点增加,是Ca2+起活化作用的主要原因.  相似文献   

8.
基于硫化矿物浮选过程中,尽管硫化矿物与石英的可浮性差异很大,但二氧化硅仍是硫化矿精矿中含量最高的杂质组分,是影响硫化矿物精矿质量的主要因素,对硫化矿物浮选体系中常见金属离子存在条件下戊基黄药浮选石英的行为规律进行了研究。研究结果表明:导致硫化矿精矿中石英含量高的主要原因之一是硫化矿浮选体系中存在的某些金属对石英具有活化浮选作用;Fe3+,Pb2+和Cu2+在合适的pH区间可以活化石英的浮选,而Ca2+,Mg2+和Fe2+对其可浮性没有明显影响;在浮选体系中,Fe3+,Pb2+,Cu2+,Ca2+,Mg2+和Fe2+这6种金属离子均可在石英表面吸附,但只有Fe3+,Pb2+和Cu2+作用后的石英表面可以吸附戊基钾黄药,从而活化石英浮选;溶液化学计算表明:金属离子的羟基络合物和氢氧化物是离子起活化作用的有效组分。  相似文献   

9.
采用生态安全型火山渣净化石油类污染地下水,考察该过程中与水化学因子(Fe2+,Fe3+,Mn2+,SO2-4,NH+4,Ca2+,Mg2+,NO-3,NO-2等)间的响应关系.结果表明:在火山渣吸附水体总石油烃(TPH)过程中,与Mn2+,SO2-4,Ca2+,NH+4的质量浓度无关,与Fe2+,Fe3+,Mg2+,NO-2的质量浓度呈负相关,与NO-3的质量浓度呈正相关;对Ca2+的去除率为42%~56%,对SO2-4,Mg2+,NH+4的去除率为60%~80%,对Fe2+,NO-3的去除率大于80%,对Fe3+,Mn2+,NO-2的去除率均大于95%.  相似文献   

10.
用Quin 2法测得大鼠脑突触体内静息游离Ca2+浓度([Ca2+]i)为85±13μmol/g protein.地西泮0.1,1和10 mmol/L对静息突触体[Ca2+]i无明显影响,但能以剂量依赖方式增高65 mmol/LKCl所致突触体[Ca2+]i升高,从105±23μmol/g protein分别达到185±28,267±49和291±48μmol/gprotein.地西泮1和10 mmol/L分别使突触体Ca2+,Mg2+-ATP酶活性降低28.7%和42.5%;使Mg2+-ATP酶活性分别降低12.6%和32.8%,提示地西泮可能是通过抑制钙调素,进而抑制Ca2+,Mg2+-ATP酶活性,使突触体[Ca2+]1升高,促进神经末梢释放递质.  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.
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   

15.
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   

16.
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   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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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