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51.
In this study, the superparamagnetic adsorbent as Fe@Mg‐Al LDH was synthesised by different methods with two steps for the removal of heavy metal ions from water samples. An easy, practical, economical, and replicable method was introduced to remove water contaminants, including heavy ions from aquatic environments. Moreover, the structure of superparamagnetic adsorbent was investigated by various methods including Fourier transform infrared spectroscopy, field emission scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and vibrating sample magnetometer. For better separation, ethylenediaminetetraacetic acid ligand was used, forming a complex with antimony ions to create suitable conditions for the removal of these ions. Cadmium and antimony ions were studied by floatation in aqueous environments with this superparamagnetic adsorbent owing to effective factors such as pH, amount of superparamagnetic adsorbent, contact time, sample temperature, volume, and ligand concentration. The model of Freundlich, Langmuir, and Temkin isotherms was studied to qualitatively evaluate the adsorption of antimony ions by the superparamagnetic adsorbent. The value of loaded antimony metal ions with Fe@Mg‐Al LDH was resulted at 160.15 mg/g. The standard deviation value in this procedure was found at 7.92%. The desorption volume of antimony metal ions by the adsorbent was found to be 25 ml. The thermodynamic parameters as well as the effect of interfering ions were investigated by graphite furnace atomic absorption spectrometry.  相似文献   
52.
Jaiki Lee 《辐射防护》2020,40(6):625-630
In May 2018,the primetime news casted a shocking report saying that radon concentration on a certain model of bed mattress found to be as high as 2 200 Bq/m3.After a humble,the Nuclear Safety and Security Commission(NSSC) of Korea confirmed that significant amount of thoron gas is emanated from several mattress models marketed by a company claiming beneficial health effects of negative ions.Laboratory analysis showed that some internal fabric sheets of those mattresses contain high co...  相似文献   
53.
The sputtering yield of Mo honeycomb walls was compared with the yield of fiat walls in a d.c. Ar glow discharge. Under the experimental condition where the mean energy is approximately 1 keV and the angle of incidence of primary ions strongly distributed around normal, the yield is reduced by a factor of 20 to 30. Before and after the bombardment, the surface topography of the honeycomb targets was observed by a scanning electron microscope.  相似文献   
54.
侯明东  孙文声 《核技术》1995,18(3):129-133
用扫描电子显微镜观测研究了室温下195keVAr+辐照非晶态合金Co(60)Fe(12)Ni(10)Si6B(12)和Fe(39)Ni(39)V2Si(12)B8在各剂量阶段的表面损伤形貌。结果表明,表面损伤是发泡和溅射相互竞争的过程。低剂量下,表面损伤以发泡为主;而在高剂量时,表面发泡消失,溅射造成的多孔粗糙表面损伤结构形成。对高剂量时表面发泡消失的可能机制作了探讨。  相似文献   
55.
循环冷却水中氯离子对板换材料选择的影响   总被引:1,自引:0,他引:1  
对板式换热器腐蚀进行了分析,结合不同氯离子含量、不同温度对不同材料的腐蚀界限,对以循环水为冷却介质的板式换热器由于冷却水氯离子含量对材料选择的影响进行了分析。  相似文献   
56.
New oxide compounds with α-PbO2 structure have been synthesized by solid-state reactions. These are derived from ZrTiO4 and HfTiO4 by a different kind of ionic substitution. The thermal expansion behavior of these phases was investigated by means of a dilatometer and an X-ray heating diffractometer. These measurements revealed rather low expansion for some of the Zr(Me3+/Me5+)O4, solid solutions. This behavior is attributed to their high expansion anisotropy, which leads to extended formation of microcracks.  相似文献   
57.
A new chelating fabrics are synthesized by radiation induced grafting of acrylonitrile (AN) onto polypropylene nonwoven fabrics (PP fabrics) and subsequent conversion of cyano to an imine by reaction with ethylene diimine (EDA). Influence of various parameters such as initial concentration, pH and adsorption time on the adsorption amount for palladium ions was investigated. It was found that adsorbent achieved excellent adsorption performance in palladium ion removal in the pH range of 1.88–5.70. The adsorption amount of ions increased with shaking time and initial concentration of palladium ions. The grafted and aminated fabrics were characterized by FT‐IR, TGA and SEM. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
58.
郭效军  李岱 《硅酸盐通报》2017,36(1):345-351
采用化学沉淀法,在模拟体液环境中制备了Na、Mg、F三元素共掺杂的羟基磷灰石( HA)粉体,利用XRD、FT-IR、SEM、EDS等技术对其物相结构、微观形貌、化学组成和热稳定性进行了分析和表征。结果表明:Na/Mg/F对HA进行掺杂引起HA晶格发生畸变。 F元素的掺杂量对HA的形貌具有一定的影响;随着F掺杂量的增加,球形的HA颗粒逐渐转变成棒状结构。 F/P=0.25时,可以制得小而均匀的HA颗粒。抑菌环实验表明Na/Mg/F共掺杂HA对金黄色葡萄球菌的生长具有一定的抑制作用。 F/P=0.25时,抗菌性最强。煅烧温度在1000℃时HA的物相未发生变化,说明样品具有良好的热稳定性。  相似文献   
59.
The electrochemical behaviour of Al, Al—In and Al–Ga–In alloys in 0.6 m NaCl solutions with and without Zn2+ was investigated. The study was performed by means of open circuit potential, potentiodynamic polarization, potentiostatic current-time and electrochemical impedance spectroscopy measurements as well as by SEM-EDAX examination. It was found that the Al—In alloy exhibits the highest negative open circuit potential in 0.6 m NaCl and the corrosion resistance of the tested electrodes decreases in the following order: Al > Al–Ga–In > Al—In. The greater activity of the Al—In alloy was interpreted on the basis of the autocatalytic attack by indium. The potentiostatic current–time measurements in Zn2+ containing electrolyte at potentials above the pitting potential revealed that Zn2+ has an insignificant influence on the Al electrode, while it enhances the corrosion of the Al–Ga–In alloy and improves the attack morphology of the Al—In alloy. Furthermore, the impedance spectra recorded under open circuit conditions showed a decrease in the polarization resistance of Al—In and Al–Ga–In alloys in presence of Zn2+ indicating the activating effect of Zn2+ ions.  相似文献   
60.
李杰  马凤国  谭惠民 《化工进展》2004,23(5):532-535
用化学改性羧甲基纤维素接枝聚丙烯酰胺(CMC-g-PAM)树脂制备了羧甲基纤维素接枝聚磺甲基化丙烯酰胺(CMC-g-SPAM)吸水树脂。采用静态法测定该强阴离子性吸水树脂对重金属离子的去除条件和去除效果。实验结果表明,该树脂对铅离子有很好的吸附脱除性能,脱除率可达95%,1g树脂可吸附2.7mg铅。X射线光电子能谱(XPS)等微观结构测试表明,吸附后重金属铅离子在吸水树脂上聚集存在,为非晶态。  相似文献   
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