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1.
用热重法研究了在CO和O2共同存在下氧化锌脱硫的微观动力学行为.研究结果表明CO对氧化锌脱除H2S反应有显著影响。φ(CO)≤10%,在有氧及无氧条件下,CO均会促进反应进行;φ(CO)≥15%会抑制反应进行,或引起严重积炭;氧的存在可抵消一部分由歧化积炭而引起的负作用.氧化锌脱硫动力学行为可用改良收缩核模型进行描述,给出了动力学参数估值.  相似文献   

2.
以Zn(Ac)2.2H2O和H2C2O4.2H2O为材料,固相合成氧化锌纳米材料.以原子吸收分光光度法(AAS)为手段检测了纳米氧化锌对Cu(Ⅱ),Co(Ⅱ),Fe(Ⅲ)的吸附洗脱性能.结果表明:在碱性条件下纳米氧化锌的吸附效果较酸性条件下好.因此,选择在酸性条件下对金属离子进行洗脱.实验测得氧化锌对上述金属离子的静态吸附容量分别为:15.3、19.1和19.5mg/g.  相似文献   

3.
针对现行的湿法炼锌渣中提取锗的研究现状,采用新型萃取剂HBL101从锌置换渣的高酸浸出液中直接萃取锗,考察了料液酸度、萃取剂体积分数、萃取温度、萃取时间和相比对萃取的影响以及氢氧化钠质量浓度、反萃温度、反萃时间和反萃相比对反萃的影响,并对萃取剂转型条件进行了研究.实验表明:有机相组成为30% HBL101+70%磺化煤油(体积分数)作为萃取剂,料液酸度为113.2 g·L-1 H2 SO4,其最佳萃取条件为萃取温度25℃,萃取时间20 min,相比O/A=1:4.经过五级逆流萃取,锗萃取率达到98.57%.负载有机相用150 g·L-1 NaOH溶液可选择性反萃锗得到高纯度锗酸钠溶液,其最佳反萃条件为反萃温度25℃,反萃时间25 min,相比O/A=4:1.经过五级逆流反萃,反萃率可达到98.1%.反萃锗后负载有机相再用200 g·L-1硫酸溶液反萃共萃的铜并转型,控制反萃温度25℃,反萃时间20 min,O/A=2:1.经过五级逆流反萃,铜反萃率可达到99.5%并完成转型,萃取剂返回使用.  相似文献   

4.
研究了用正-丁基辛基亚砜萃取、S-丁基异硫脲盐反萃金(Ⅲ)的行为.实验结果表明萃合物的组成为H_3O(n-BOSO)_3AuCl_4,反萃金(Ⅲ)是离子交换机理,金(Ⅲ)萃合物用元素分析、热分析、摩尔电导、UV和IR光谱进行了表征。  相似文献   

5.
对锗烟尘中氧化锌酸浸的动力学和反应机制进行了研究。结果表明,锗烟尘中氧化锌酸浸属于生成固体产物层的“未反应核缩减型”模型,动力学方程遵从1—2α/3-(1-α)^2/3=kt,锗烟尘中氧化锌酸浸的反应为一级反应,其表现活化能11.442kJ/mol,浸出过程为扩散步骤所控制。提高酸的浓度、温度、搅拌强度均可加快锌浸出速度,提高浸出率。  相似文献   

6.
以Ce(NO3)3.6H2O为铈源,(NH4)2 CO3.H2O为沉淀剂,加入少量PEG4000作为分散剂,采用化学沉淀法并经水洗、超声波醇洗,70℃干燥后得到CeO2的前驱体Ce2(CO3)3.H2 O。对Ce2(CO3)3.H2 O样品运用差示/热重分析(DSC/TG)和X射线衍射(XRD)方法进行其热分解过程研究,并通过多重速率扫描法记录样品在不同升温速率下的DSC/TG曲线,采用Kissinger-Akahira-Sunose(KAS)法和Coats-Redfern法进一步研究Ce2(CO3)3.H2 O的热分解动力学。研究结果表明:Ce2(CO3)3.H2 O热分解反应过程分2步进行,主要反应阶段的反应动力学参数是:反应活化能为105.51 kJ/mol,反应级数为2,频率因子为3.61;由此推断出可能的Ce2(CO3)3.H2 O热分解机理函数为Anti-Jander方程,受三维扩散机制控制。  相似文献   

7.
用放射性同位素198Au示踪法研究了乙二醇(GLY)、二羟乙基硫醚(DGTE)等对季铵盐载金有机相的反萃,考察了反萃剂的浓度、有机相与反萃剂的体积比(R)、加入乙醇等对反萃率(S)的影响.讨论了有机相反萃后继续萃取的问题.结果表明,GLY,DGTE在较高体积分数时都是很好的反萃剂.当GLY体积分数大于90%、DGTE体积分数大于70%时,其反萃能力均可达到90%.反萃剂中不含乙醇时,反萃后有机相具备连续萃取的能力.实验还发现,NaClO4和NH4SCN也有很好的反萃作用.  相似文献   

8.
在实验室模拟条件下,以粉煤灰改性污泥为垃圾填埋场生物覆盖材料,分析了初始甲烷浓度、初始氧气浓度对甲烷氧化效率的影响,并测定了甲烷氧化动力学方程及动力学参数,旨在为材料实际工程应用提供理论依据.结果表明:初始CH4、O2浓度制约生物覆盖材料的甲烷氧化效率,初始CH4、O2浓度越高,材料甲烷氧化能力越强;甲烷氧化过程符合2级动力学方程-dV(CH4)/dt=kV(CH4)V(O2);利用Michaelis-Menten模型得出覆盖层材料的最大氧化速率Vmax为2.54 μmol g-1h-1,半速常数Km为0.49 μmol.  相似文献   

9.
基于田口方法,提出了采用萃取剂LIX984N从高铁生物浸出液中萃铜工艺的优化方法,对萃取率及反萃率进行信噪比分析和方差分析.结果表明,萃取过程中,萃取剂体积分数和相比对萃取率的贡献率较大,分别达到32744%,34180%,时间为较重要因素,pH值对信噪比影响较小.优化后的工艺参数:萃取剂体积分数为30%,相比(V(O)/V(A))为2∶1,时间为600s,pH值为15;反萃过程中,相比及时间为显著因子,温度为不显著因子.优化后的工艺参数:相比(V(O)/V(A))为1∶2,时间为600s,反萃温度为30℃.在优化后的条件下进行萃取—反萃—电积实验,萃取率达到9991%,反萃率达到9856%,电流效率达到92594%.  相似文献   

10.
为了研究纳米γFe2O3催化剂选择性催化还原法(SCR)脱硝反应机理,采用微分反应器测量了纳米γFe2O3催化剂上SCR反应的动力学参数,并构建了SCR反应动力学模型.实验数据分析结果表明,NH3,NO和O2的反应级数分别为0,0.78~0.93和0.09~0.11,反应活化能为57.3 k J/mol.原位红外漫反射光谱(DRIFTS)实验结果表明:NH3能够强吸附到催化剂表面并达到饱和,进一步增加NH3的浓度并不能增加NO的转化速率;NO在有氧条件下能吸附到催化剂表面生成吸附态NO2和亚硝酸盐;在低于270℃的情况下SCR反应遵循Langmuir-Hinshelw ood(L-H)反应机理,在高于270℃的情况下则主要遵循Eley-Rideal(E-R)反应机理.  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.
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   

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

18.
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   

19.
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   

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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