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1.
利用XRD考察了固溶或吸附Na+离子和Al3+离子的C-S-H在压蒸条件下形成沸石的可能性并对C-S-H中沸石形成条件进行了讨论,沸石形成的难易程度与C-S-H的稳定程度有关,也可能与形成沸石所需要的各种氧化物可供给的比例有关.  相似文献   

2.
研究了Al3+离子的固溶对C-S-H表面吸附Na+离子量的影响.实验结果表明,Al3+离子固溶于C-S-H结构中将使C-S-H表面所带的负电量增大,因而也就增大了C-S-H表面对Na+离子的吸附能力.  相似文献   

3.
应用表面物理化学理论,分析了C-S-H在不同浓度、不同种类氯化物溶液中浸泡后ζ电位发生变化的原因,并在此基础上推测了被吸附的C1-离子在C-S-H表面上的分布状态。C1-离子似乎是C-S-H的特性吸附离子,只要C-S-H浸泡于氯化物溶液中,C1-离子将优先进入吸附层。吸附于C-S-H表面的C1-离子的总量包括吸附层中的C1-离子量和扩散层中的C1-离子量。随浸泡液中C1-离子浓度的增大,C1-离子不断进入吸附层,但吸附层的空间是有限的,吸附层中C1-离子增加的速度逐渐减慢。扩散层的C1-离子量取决于ζ电位的大小。在较高浓度的A lC l3溶液中浸泡的C-S-H对C1-离子的吸附量显著增大,由于此时双电层已显著变薄,因而不能忽略C-S-H表面长程范氏力对C1-离子的吸引作用。  相似文献   

4.
采用热力学离子交换平衡的实验方法测试了K型白庙子斜发沸石上2K^+(z)→←Cu^2+(s)交换体系在不同温度,不同Cu^2+初始浓度时的Cu^2+平衡交换量Q∞交换效率η离子校正选择离子K,分离系数α以及△rGm,△rSm等热力学数据,实验结果表明,该矿样上Q∞,η,Kc,α等均受交换温度和溶液Cu^2+初妈浓度的影响,其中,浓度的影响与电解质溶液的熵效应,溶液的非理想程度均有关。并且,随着交换  相似文献   

5.
应用表面物理化学理论,分析了C-S-H在不同浓度、不同种类氯化物溶液中浸泡后ζ电位发生变化的原因,并在此基础上推测了被吸附的C1-离子在C-S-H表面上的分布状态.C1-离子似乎是C-S-H的特性吸附离子,只要C-S-H浸泡于氯化物溶液中,C1-离子将优先进入吸附层.吸附于C-S-H表面的C1-离子的总量包括吸附层中的C1-离子量和扩散层中的C1-离子量.随浸泡液中C1-离子浓度的增大,C1-离子不断进入吸附层,但吸附层的空间是有限的,吸附层中C1-离子增加的速度逐渐减慢.扩散层的C1-离子量取决于ζ电位的大小.在较高浓度的AlCl3溶液中浸泡的C-S-H对C1-离子的吸附量显著增大,由于此时双电层已显著变薄,因而不能忽略C-S-H表面长程范氏力对C1-离子的吸引作用.  相似文献   

6.
测定了所合成纳型丝光沸石在碱金属离子混合溶液中的分配系数、饱和度换容量及对K^+、Na^+的pH滴定曲线。结果表明该沸石对K^+选择性大于其它碱金属离子。  相似文献   

7.
干湿循环法制备抗菌性 5A 沸石   总被引:10,自引:2,他引:8  
本文探索了制备抗菌性沸石的新方法———干湿循环处理法,采用5A沸石分别与抗菌性离子Zn2+、Ag+、Cu2+的溶液进行干湿循环处理,制备抗菌性5A沸石。研究了反应条件,如温度、浓度、循环次数对沸石中抗菌性离子含量的影响,找出了最佳反应条件。测试了抗菌性5A沸石的耐洗涤性能和抗菌性5A沸石对黑曲霉菌、大肠杆菌及嗜热脂肪芽胞杆菌的抗菌效果。研究结果表明,干湿循环法制备抗菌性沸石,具有抗菌性离子含量多,抗菌性能好,方法简便,反应时间短,节约原料等优点。  相似文献   

8.
本文用XRD,XPS,IR能谱研究载钴沸石试佯Co/ZSM-5(Imp-x)的物种和预处理条件对载钴沸石还原性的影响。观察到运用浸渍法时,有部分Co~(2+)进入孔道内与H~+进行交换.形成类Co(OH)_2的物种,而内部的Co~(2+)不易被还原。试样焙烧时,大部分钴离子以Co_3O_4形式存在于沸石的外表面。载钴沸石经高温焙烧后,表面富铝,並随载钴量的增加而增加。在高温焙烧过程中,随载钴量增加,Co~(2+)和Al_2O_3相互作用形成CoAl_2O_4的可能性增大,而CoAl_2O_4即使在高温下也不易被还原,这导致载钴沸石还原度减小。载钴沸石还原度的大小,与焙烧温度,钴载量,还原条件(还原温度、时间等因素)有关。  相似文献   

9.
铜型抗菌沸石的合成与应用   总被引:9,自引:1,他引:8  
介绍液固,固相离子交换法将沸石与具有抗菌性能的铜离子合成抗菌沸石,用正交法确定了两种方法的较佳条件,并进行比较,尝试利用微波加热法合成的抗菌沸石,此外探讨了自制铜型抗菌沸石作为毒料的船底防污漆的可行性。  相似文献   

10.
采用3-氨基丙基三甲氧基硅烷对天然斜发沸石进行改性,利用傅里叶变换红外光谱仪、X射线衍射仪、比表面积及孔隙度分析仪和综合热分析仪等对材料进行表征,采用饱和水蒸气吸附法评价材料的表面疏水性,采用重铬酸根离子、甲基橙和亚甲基蓝染料分别评价材料的吸附性.结果表明,氨基硅烷偶联剂改性显著提高了沸石的疏水性;偶联剂改性量为1.5∶5时,改性沸石的水蒸气吸附量为26.7mg/g,显著低于沸石的66mg/g.由于氨基基团在酸性条件下荷正电,制备的氨基功能化沸石对重铬酸根离子的去除率较沸石显著提高;相同条件下,改性沸石对重铬酸根离子溶液的脱色率达到92.9%,而未改性沸石仅为1.59%.由于偶联剂改性提高了沸石的疏水性,降低了沸石的比表面积和孔径,导致制备的氨基功能化沸石对甲基橙和亚甲基蓝的去除率较沸石有所降低;相同条件下,改性沸石对甲基橙和亚甲基蓝溶液的脱色率分别为70.88%和97.14%,均低于沸石的100%.  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.
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   

18.
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   

19.
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   

20.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

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