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1.
在260℃高压溶出黄铁矿制备高硫高铁的铝酸钠溶液,研究溶液温度、保温时间、苛性比(αk)以及Na_2CO_3,Na_2SO_4和Na_2C_2O_4等杂质对溶出液中铁质量浓度的影响。研究结果表明:溶液温度为50℃和60℃时,随着保温时间的延长,溶液中铁质量浓度略有降低;苛性比为3.0左右时,随着Na_2CO_3质量浓度的升高,溶液中铁质量浓度略有升高,而Na_2SO_4和Na_2C_2O_4质量浓度的升高则能显著提高溶液中的铁质量浓度;随着溶液苛性比的升高,溶液中铁质量浓度在苛性比为2.0~2.5之间有1个急剧升高的区间,然后逐渐趋于稳定。  相似文献   

2.
苛性比对铝酸钠溶液结构和性质的影响   总被引:4,自引:0,他引:4  
用红外光谱和粘度测定手段考察了苛性比对铝酸钠溶液结构和性质的影响·发现在中等浓度以上的铝酸钠溶液中,当ρAl2O3不变时,随着苛性比的增加Al O Al峰减弱至消失;Al(OH)-4的峰减弱·温度在70℃以下,铝酸钠溶液的粘度随苛性比增加而大幅度增加,高于70℃增加较小·用铝酸钠溶液中铝酸根阴离子与OH-形成缔合物解释铝酸钠溶液的红外光谱和粘度随苛性比的变化·  相似文献   

3.
提高氧化铝种分率的研究   总被引:1,自引:1,他引:0  
对影响拜耳法种分分解率的各主要因素,精液苛性比αk溶液Al2O3浓度CA、晶种系数及加入方法,分解温度和降温制度进行了分析论证,并提出改善这些 有效途径。  相似文献   

4.
研究了1,6-二磷酸果糖溶液在不同酒精浓度和pH下的溶解度以及不同1,6-二磷酸果糖溶液的浓度、温度及pH下的粘度,并给出了浓度对粘度的关联式.实验发现,溶液的温度和pH对溶液的粘度有很大的影响,因此升高溶液的温度和降低溶液的pH有利于改善溶液的传质状况和结晶条件,为1,6-二磷酸果糖的结晶新体系的研究提供依据.  相似文献   

5.
铝酸钠溶液中二氧化硅的平衡浓度   总被引:9,自引:0,他引:9  
基于组成类似的化合物热力学数据与组成存在的线性关系,计算了4种钠硅渣的热力学数据,并计算了在铝酸钠溶液中形成钠硅渣后二氧化硅平衡浓度与温度或苛性比的关系·计算结果表明,二氧化硅平衡浓度计算值与实验值相符;同时,随着温度的升高或苛性比的增大,铝酸钠溶液中二氧化硅平衡浓度也随之增大  相似文献   

6.
通过合成高活性氢氧化铝净化铝酸钠溶液中的锂,考察不同反应条件对沉锂效果的影响,并对除锂反应机理进行研究。通过XRD和SEM分析,对沉锂产物进行表征。基于不同条件下沉锂率与反应时间的关系,构建Avrami动力学方程。研究结果表明:在苛性比α_k(即溶液中Na_2O_k与Al_2O_3物质的量比)为1.45的铝酸钠溶液中,控制温度为353 K,高活性氢氧化铝添加量为1.3 g/L,反应时间为120 min,沉锂率可达80.04%;高活性氢氧化铝与溶液中锂离子发生沉淀反应,其沉锂产物为Li_2Al_4(CO_3)(OH)_(12)·3H_2O;在348~363 K温度范围内,沉锂过程的表观活化能E_a=16.474 kJ/mol,指前因子A=160.355 min~(-1),速率常数k可以表示为k=160.355×e~((-16.474)/(RT))。  相似文献   

7.
在热力学计算的基础上,研究CaCO3在铝酸钠溶液体系中发生反苛化反应的规律.热力学计算表明,低温条件下,CaCO3与游离苛性碱形成Ca(OH)2的反苛化程度较小,而其与Al(OH)4-形成3CaO·Al2Oy6H2O(C3AH6)的反苛化反应显著.CaCO3在纯NaOH溶液中反苛化反应的反应率小于5%,而在铝酸钠溶液中其反苛化率可达50%以上,说明Al(OH)4-对CaCO3的反苛化具有显著的促进作用;CaCO3的反苛化率随温度的升高而升高,随铝酸钠溶液苛性比αk的升高呈先升高后降低的规律,当αk为3时,出现极大值;常压条件下,CaCO3在铝酸钠溶液中发生反苛化反应形成C3AH6,而造成氧化铝损失.  相似文献   

8.
魔芋胶的流变性研究   总被引:4,自引:0,他引:4  
对魔芋胶的流变性进行了研究.结果表明:浓度、剪切力、溶解温度、加热时间、pH值、冻融等变化与魔芋胶的粘度有较大关系;魔芋胶溶液具有较高的粘度,当浓度达到1%时,其粘度为428mPa/s;魔芋胶溶液为"非牛顿流体";加热时间与温度对魔芋胶粘度影响较大;魔芋胶溶液在酸性和碱性条件下都较为稳定;冻融处理后魔芋胶粘度下降.魔芋胶与黄原胶、卡拉胶有强烈的协效性,与皂荚胶的协效性较低.  相似文献   

9.
果胶溶液粘度的研究   总被引:1,自引:0,他引:1  
本文研究了浓度、温度、酸度、Ca2+、糖等因素对果胶溶液粘度的影响,在酸度为0.9gHCl/10Oml下来胶容液的粘度最低、而Ca2+,糖在研究的范围内对果胶溶液粘度的影响不大。  相似文献   

10.
以母液苛性比和结晶率为考察指标,对高铝粉煤灰水热法浸出液结晶铝酸钠的行为进行了研究。主要考察了Na_2O浓度、结晶时间、结晶温度和晶种添加量对铝酸钠结晶的影响。结果表明,铝酸钠溶液中氧化钠浓度的升高和结晶时间的延长,有利于提高铝酸钠结晶率。但升高温度,会导致铝酸钠结晶率小幅下降。其次,研究还发现添加晶种能显著提高铝酸钠的结晶率,但晶种添加量对铝酸钠结晶影响不大。水合铝酸钠结晶工序优化的操作条件为:Na_2O浓度600 g/L、结晶温度60℃、晶种添加量20g/L、结晶时间16h。在此条件下,铝酸钠结晶率达到66.67%,结晶母液苛性比超过了25,能够满足循环溶出的要求。结晶获得的固相主要是水合铝酸钠,分子式为4NaAlO_2·5H_2O。  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.
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   

18.
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   

19.
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   

20.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

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