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1.
采用共沉淀法制备了四元体系ZnO-Fe2O3-Na2O-P2O5作为太阳热反射材料.用紫外-可见光-近红外分光光度计、XRD对产物进行表征.结果表明:当Zn/Fe摩尔比为9.00、在700℃下煅烧时,产物的物相组成随Zn/P摩尔比(1.52、1.02、0.76、0.61)而变化,其中Zn/P摩尔比为0.61的产物为空间群P21/n的单相NaZnPO4结构,其余Zn/P摩尔比下的产物为多相结构;当Zn/P摩尔比为0.61、在700℃下煅烧时,不同Zn/Fe摩尔比(19.00、9.00、5.67、4.00)的产物均为单相NaZnPO4结构,且随Zn/Fe摩尔比降低,产物颜色加深,反射比降低;当Zn/P摩尔比为0.61、Zn/Fe摩尔比为9.00时,500~800℃煅烧温度范围内的产物均为单相NaZnPO4结构,且随煅烧温度增加,产物颜色加深,反射比降低,其中,600℃煅烧产物呈橘红色且近红外波段反射比为80.7%,700℃煅烧产物呈红色且近红外波段反射比为72.2%.  相似文献   

2.
新型无机高分子复合絮凝剂聚合硅酸铝铁混凝效果研究   总被引:1,自引:0,他引:1  
以AlCl3·6H2 O ,FeCl3·6H2 O ,硅酸钠和盐酸为原料 ,以无水碳酸钠为碱化聚合剂 ,制备出了一系列聚合硅酸铝铁 (PAFSC)复合无机高分子絮凝剂 ;通过烧杯实验 ,比较了PAFSC和PAC对各种水样的混凝效果 .结果表明 :PAFSC较PAC具有更好的混凝效果 ;其制备工艺、Al Fe Si摩尔比对PAFSC的混凝效果有一定的影响 ,在Al Fe Si摩尔比一定的情况下 ,共聚法制备的PAFSC(共 )的混凝效果优于复合法制备的PAFSC(复 )的混凝效果 ;在制备工艺一定的情况下 ,随着Al Fe Si摩尔比中Fe和Si摩尔数增加 ,PAFSC絮凝剂的混凝效果变好 .此外 ,pH值对PAFSC的混凝效果也有一定的影响 .  相似文献   

3.
通过酸浸法对粉煤灰进行改性,并适量的补加SiO2、Al3+、Fe3+,从而制得集物理吸附和化学混凝为一体的粉煤灰基混凝剂,用这种混凝剂处理水基切削液废液,研究了不同因素对废液CODCr去除率的影响,并通过正交实验得出最佳的工艺处理条件:废液处理前稀释3倍,混凝剂投加量为6mL/L,SiO2添加量为0.05 mol/L,Al3++Fe3+添加量为0.04mol/L,Al3+:Fe3+摩尔比为4:1,在此条件下废液CODCr去除率大于98%.  相似文献   

4.
以氯化铝、硫酸铁为主要原料制备了系列聚合氯化硫酸铝铁(PAFCS)絮凝剂.探讨了不同A1/Fe摩尔比、碱化度B、稳定剂用量、投加量等因素对混凝效果的影响,并考察了PAFCS预处理垃圾渗滤液的混凝效果.结果表明:在pH=6-8、A1/Fe摩尔比为4∶1、B=1.0、[A l] [Fe]=0.08 mol/L时混凝效果最佳,各项混凝性能都明显优于PAC和PFS.  相似文献   

5.
采用铝酸钠种子分解法制备超细Al(OH)_3。用X射线衍射仪(XRD)表征了样品的晶相组成,用扫描电子显微镜(SEM)观察了样品的形貌,用激光粒度分析仪测定样品的粒度分布。研究了NaOH浓度、NaOH/Al(OH),摩尔比,分解温度,分解时间、晶种率和搅拌速率等因素对AL(OH)_3的粒度的影响。结果表明:NaOH浓度越高,分解温度越低,NaOH/Al(OH),摩尔比越小,得到的Al(OH),颗粒的粒度越小。试验条件为:NaOH浓度180 g/L,NaOH/Al(OH),摩尔比1.15,分解温度40℃,分解时间26 h,晶种率8%,搅拌速率200 rpm时,氢氧化铝颗粒的平均粒度为2.89μm。  相似文献   

6.
采用铝酸钠种子分解法制备超细Al(OH)_3。用X射线衍射仪(XRD)表征了样品的晶相组成,用扫描电子显微镜(SEM)观察了样品的形貌,用激光粒度分析仪测定样品的粒度分布。研究了NaOH浓度、NaOH/Al(OH),摩尔比,分解温度,分解时间、晶种率和搅拌速率等因素对AL(OH)_3的粒度的影响。结果表明:NaOH浓度越高,分解温度越低,NaOH/Al(OH),摩尔比越小,得到的Al(OH),颗粒的粒度越小。试验条件为:NaOH浓度180 g/L,NaOH/Al(OH),摩尔比1.15,分解温度40℃,分解时间26 h,晶种率8%,搅拌速率200 rpm时,氢氧化铝颗粒的平均粒度为2.89μm。  相似文献   

7.
以Ca(OH)_2和Al(OH)_3为原料清洁制备焙烧态水铝钙石,采用CO_2程序升温吸脱附法表征其碱强度和碱量,并将其应用于酯交换合成单硬脂酸甘油酯(glycerol monostearate,GMS)。考察了焙烧态水铝钙石的制备条件与酯交换反应条件对合成GMS的影响。结果表明,当原料中Ca/Al摩尔比为2∶1,焙烧温度600℃时,制备的焙烧态水铝钙石的催化性能最优。在优化反应条件下,粗产物中GMS的含量高达80.4%。  相似文献   

8.
强化混凝去除腐殖酸的试验研究(英文)   总被引:1,自引:0,他引:1  
选用Al2(SO4)3、FeCl3混凝剂对腐殖酸的强化混凝试验表明,强化混凝对腐殖酸有很好的去除效果。pH值和混凝剂投加量是影响腐殖酸处理效率的主要因素,其中调整pH值更有效。Al2(SO4)3混凝的最佳pH值在5左右,FeCl3在4左右。Al2(SO4)3投加量为4mg/L时,DOC、CODMn及UV254去除率可分别达到69.7%、84.8%和96.9%。FeCl3投加量为5mg/L时,DOC、CODMn及UV254去除率可分别达到78.1%、89.3%和97.8%。  相似文献   

9.
聚硅酸铝的絮凝性及稳定性研究   总被引:3,自引:0,他引:3  
在制备聚硅酸氯化铝(PSAC)和聚硅酸硫酸铝(PSAS)的基础上,考察了水玻璃浓度,Al/Si摩尔比对聚硅酸氯化铝稳定性的影响,研究了水玻璃浓度;Al/Si摩尔比,铝盐种类,放置时间和搅拌强度对聚硅酸铝絮凝沉降效果的影响规律,结果表明,聚硅酸铝的稳定性随水玻璃浓度增加而降低;PSAS与PSAC絮凝性能的差异和Al/Si摩尔比密切相关,PSAC在Al/Si摩尔比为0.75-1时絮凝效果较好,而PSAS在Al/Si摩尔比较低时絮凝效果好,搅拌强度和放置时间也明显影响药剂的絮凝效果。  相似文献   

10.
粉煤灰制备聚硅硫酸铝及絮凝性能研究   总被引:1,自引:0,他引:1  
以粉煤灰为主要原料制备了具有不同铝硅摩尔比的聚硅硫酸铝(PASS)混凝剂,研究表明制备PASS的最佳铝硅摩尔比为1:1;模拟废水混凝实验表明,PASS具有用药量少、絮体沉降性能好、适用范围广等优点;利用粉煤灰制备高效无机高分子混凝剂聚硅硫酸铝,工艺较简单、生产成本低,而且使粉煤灰中的主要成分硅、铝同时得到了充分利用,是粉煤灰综合利用的一条新途径.  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.
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   

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 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   

15.
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   

16.
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   

17.
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   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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