Artigos de revistas: "Zn and Sn based promoters"

1

Yang, Chenjun, Mengwei Chen, Jiaqi Wang e Haifei Lu. "Zn-Doped SnO2 Compact Layer for Enhancing Performance of Perovskite Solar Cells". International Journal of Photoenergy 2021 (22 de junho de 2021): 1–10. http://dx.doi.org/10.1155/2021/9920442.

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Perovskite solar cells (PSCs) have been developing rapidly since they were discovered, and their excellent photoelectric properties have attracted wide attention from researchers. The compact layer is an important part of PSCs, which can transport electrons and block holes. SnO2 is an excellent and commonly used electron transport layer (ETL) material, and doping modification is an effective way to improve performance. Here, Zn with a similar radius to Sn has been introduced to the doping of the SnO2 compact layer to achieve the purposes of conductivity enhancement of the compact layer and followed photoelectric performance improvement of the device. Zn-SnO2 compact layers with different doping concentrations were prepared and applied to mesoporous architecture PSCs. When the doping content was 5%, the power conversion efficiency (PCE) of the device based on the Zn-SnO2 compact layer has increased from 9.08% to 10.21%, with an increase of 12.44%. The doping of SnO2 promotes its application in low-cost PSCs.

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Ali, Arshid M., Abdulrahim A. Zahrani, Muhammad A. Daous, Seetharamulu Podila, Majid Khalid Alshehri, Sami-ullah Rather e Usman Saeed. "Sequential and/or Simultaneous Wet-Impregnation Impact on the Mesoporous Pt/Sn/Zn/γ-Al2O3 Catalysts for the Direct Ethane Dehydrogenation". Journal of Nanomaterials 2022 (23 de fevereiro de 2022): 1–17. http://dx.doi.org/10.1155/2022/8739993.

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This study is aimed at investigating the impact of catalyst preparation’s approach (either sequential and/or simultaneous wet impregnation) to a mesoporous series of Pt/A, Sn/A, PtSn/A, SnPt/A, (PtSn)/A, (PtSn)Zn/A, and (PtSnZn)/A catalysts for direct ethane dehydrogenation. The (PtSn)/A and (PtSnZn)/A had shown both higher initial specific activity (s-1) and reaction rate constant K d (h-1) (13063.86 (s-1) and 12489.69 (s-1) and 0.09 (h-1) and 0.06 (h-1)), respectively. The catalyst preparation approach had direct impact to the availability and dispersion of mesoporous particles of either active metal and/or promoter that influences either to hinder the C-C cleavage and/or to promote C-H bond cleavage in the dehydrogenation of ethane to ethene. The active metal component was present in the form of Pt, Pt+2, Al+3, Sn+4, and Zn+2 states. The enhanced catalytic activity is attributed to the Pt4Sn and PtZn formed phases in addition to highly dispersed mesoporous Pt particles. Based on the obtained results, the catalysts prepared by using simultaneous wet impregnation had shown higher catalytic activity and catalyst stability as to that of sequential wet impregnation.

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Shi, Qi, Yongjun Ji, Wenxin Chen, Yongxia Zhu, Jing Li, Hezhi Liu, Zhi Li et al. "Single-atom Sn-Zn pairs in CuO catalyst promote dimethyldichlorosilane synthesis". National Science Review 7, n.º 3 (28 de novembro de 2019): 600–608. http://dx.doi.org/10.1093/nsr/nwz196.

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Abstract Single-atom catalysts are of great interest because they can maximize the atom-utilization efficiency and generate unique catalytic properties; however, much attention has been paid to single-site active components, rarely to catalyst promoters. Promoters can significantly affect the activity and selectivity of a catalyst, even at their low concentrations in catalysts. In this work, we designed and synthesized CuO catalysts with atomically dispersed co-promoters of Sn and Zn. When used as the catalyst in the Rochow reaction for the synthesis of dimethyldichlorosilane, this catalyst exhibited much-enhanced activity, selectivity and stability compared with the conventional CuO catalysts with promoters in the form of nanoparticles. Density functional theory calculations demonstrate that single-atomic Sn substitution in the CuO surface can enrich surface Cu vacancies and promote dispersion of Zn to its atomic levels. Sn and Zn single sites as the co-promoters cooperatively generate electronic interaction with the CuO support, which further facilitates the adsorption of the reactant molecules on the surface, thereby leading to the superior catalytic performance.

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Gong, Nengfeng, Gaolei Qin, Pengfei Li, Xiangjie Zhang, Yan Chen, Yong Yang e Peng He. "Enhanced Stability and Selectivity in Pt@MFI Catalysts for n-Butane Dehydrogenation: The Crucial Role of Sn Promoter". Catalysts 14, n.º 11 (29 de outubro de 2024): 760. http://dx.doi.org/10.3390/catal14110760.

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The dehydrogenation of n-butane to butenes is a crucial process for producing valuable petrochemical intermediates. This study explores the role of oxyphilic metal promoters (Sn, Zn, and Ga) in enhancing the performance and stability of Pt@MFI catalysts for n-butane dehydrogenation. The presence of Sn in the catalyst inhibits the agglomeration of Pt clusters, maintaining their subnanometric particle size. PtSn@MFI exhibits superior stability and selectivity for butenes while suppressing cracking reactions, with selectivity for C1–C3 products as low as 2.1% at 550 °C compared to over 30.5% for Pt@MFI. Using a combination of high-angle annular dark-field scanning transmission electron microscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis, and Raman spectroscopy, we examined the structural and electronic properties of the catalysts. Our findings reveal that Zn tends to consume hydroxyl groups and substitute framework sites, and Ga induces more defective sites in the zeolite structure. In contrast, the interaction between SnOx and the zeolite framework does not depend on reactions with hydroxyl groups. The incorporation of Sn significantly prevents Pt particle agglomeration, maintaining smaller Pt particle sizes and reducing coke formation compared to Zn and Ga promoters. Theoretical calculations showed that Sn increases the positive charge on Pt clusters, enhancing their interaction with the zeolite framework and reducing sintering, albeit with a slight increase in the energy barrier for C-H activation. These results underscore the dual benefits of Sn as a promoter, offering enhanced structural stability and reduced coke formation, thus paving the way for the rational design of more effective and durable catalysts for alkane dehydrogenation and other high-value chemical processes.

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Musa, Sayyidah Amnah, Mohd Arif Anuar Mohd Salleh e Saud Norainiza. "Zn-Sn Based High Temperature Solder - A Short Review". Advanced Materials Research 795 (setembro de 2013): 518–21. http://dx.doi.org/10.4028/www.scientific.net/amr.795.518.

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The developments of lead-free solders have become a major concern to the researchers in electronic industry to replace the lead-containing materials. The concern is not just for low temperature solders but also for high temperature solders. The lead and lead-based compound are highly toxic which is dangerous to human health and environment. The highly suitable lead-free solder candidates for replacing high Pb high temperature solder are Au-Sn, Al-Zn, Zn-Sn, Sn-Sb, and Bi-Ag solders. However, Zn-Sn based solder has highly recommended as the best candidates in replacing high lead high temperature solder. This paper provides a short review of recent research on Zn-Sn based lead free high temperature solders with different additional alloying elements. The new novel alloy of Zn-Sn based for high temperature solder applications will be proposed in this paper.

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Zheng, Xiali, Wei Luo, Yun Yu, Zebin Xue, Yifan Zheng e Zongjian Liu. "Metal Emulsion-Based Synthesis, Characterization, and Properties of Sn-Based Microsphere Phase Change Materials". Molecules 26, n.º 24 (9 de dezembro de 2021): 7449. http://dx.doi.org/10.3390/molecules26247449.

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A comparative study of the metal emulsion-based synthesis of Sn-based materials in two different types of molten salts (namely LiCl–KCl–CsCl and LiNO3-NaNO3-KNO3 eutectics) is presented, and the properties of Sn, Sn-Cu and Sn-Cu-Zn microsphere phase change materials prepared in chloride salts are evaluated by differential scanning calorimetry (DSC) to understand the effect of element doping. Despite a high ultrasonic power (e.g., 600 W or above) being required for dispersing liquid Sn in the chloride system, well-shaped Sn microspheres with a relatively narrow size range, e.g., about 1 to 15 µm or several micrometers to around 30 µm, can be prepared by adjusting the ultrasonic power (840–1080 W), sonication time (5–10 min) and the volume ratio of salts to metal (25:1–200:1). Such a method can be extended to the synthesis of Sn-based alloy microspheres, e.g., Sn-Cu and Sn-Cu-Zn microspheres. In the nitrate system, however, a very low ultrasonic power (e.g., 12 W) can be used to disperse liquid Sn, and the particles obtained are much smaller. At low ultrasonic power (e.g., 12 W), the particle size is generally less than 10 or 4 µm when the sonication time reaches 2 or 5 min, and at high ultrasonic power, it is typically in the range of hundreds of nanometers to 2 µm, regardless of the change in ultrasonic power (480–1080 W), irradiation time (5–10 min), or volume ratio of salts to metal (25:1–1000:1). In addition, the appearance of a SnO phase in the products prepared under different conditions hints at the occurrence of a reaction between Sn droplets and O2 in situ generated by the ultrasound-induced decomposition of nitrates, and such an interfacial reaction is believed to be responsible for these differences observed in two different molten salt systems. A DSC study of Sn, Sn-Cu, and Sn-Cu-Zn microspheres encapsulated in SiO2 reveals that Cu (0.3–0.9 wt.%) or Cu-Zn (0.9 wt.% Cu and 0.6% Zn) doping can raise the onset freezing temperature and thus suppress the undercooling of Sn, but a broad freezing peak observed in these doped microspheres, along with a still much higher undercooling compared to those of reported Sn-Cu or Sn-Cu-Zn solders, suggests the existence of a size effect, and that a low temperature is still needed for totally releasing latent heat. Since the chloride salts can be recycled by means of the evaporation of water and are stable at high temperature, our results indicate that the LiCl–KCl–CsCl salt-based metal emulsion method might also serve as an environmentally friendly method for the synthesis of other metals and their alloy microspheres.

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7

Chen, Kang I., Shou Chang Cheng e Chin Hsiang Cheng. "The Effects of Small Additions Ga and Al on the Microstructure and Tensile Properties of Sn-Zn Based Lead-Free Solders". Advanced Materials Research 800 (setembro de 2013): 265–70. http://dx.doi.org/10.4028/www.scientific.net/amr.800.265.

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The melting temperature, microstructures, and mechanical properties of the Sn-Zn-0.5Ag-0.5Ga, Sn-Zn-0.5Ag-0.45Al and Sn-Zn-0.5Ga-0.45Al lead-free solders were investigated. The results indicate that the addition of 0.5 wt% Ag to the Sn-Zn based alloys destroy the eutectic structure and results in the formation of Ag-Zn compound and hypoeutectic structure. The variation in the microstructure lowers the UTS. By the addition of Al the UTS and elongation of the 0.5Ag-0.45Al alloy can be decreased due to the Al diffused to the interface of the Ag-Zn compound/Sn-Zn eutectic structure to form Al-Zn compound. The 0.5Ga-0.45Al alloy shows a typical eutectic structure with the light contract β-Sn and the darker needle-like phase, as well as a small amount of Al-Zn phase with a near diamond shape. Gallium uniformly distributes in the Sn matrix and Zn rich phases. The 0.5Ga-0.45Al solder had the highest UTS and elongation, while 0.5Ag-0.45Al had the lowest UTS and elongation. The results indicate that Ga and Al exhibits prominent influence on the microstructure as well as the mechanical properties of the solders.

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8

Yang, S. C., C. E. Ho, C. W. Chang e C. R. Kao. "Strong Zn concentration effect on the soldering reactions between Sn-based solders and Cu". Journal of Materials Research 21, n.º 10 (outubro de 2006): 2436–39. http://dx.doi.org/10.1557/jmr.2006.0320.

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The acute Zn concentration sensitivity of the reaction between Sn-based solders and Cu substrate is reported and explained in this article. Three Sn-xZn solders (x = 0.5, 0.7, and 2 wt%) were reacted with Cu substrates at 250 °C for 2–10 min. A slight variation in the Zn concentration changed the reaction product formed at the interface. When the Zn concentration was low (x = 0.5 wt%), the reaction product was Cu6Sn5. When the Zn concentration was slightly increased to 2 wt%, the reaction product became Cu5Zn8. When Zn concentration was in-between (x = 0.7 wt%), Cu6Sn5 and CuZn co-existed. The above findings are explained using the Cu–Sn–Zn phase diagram. The implication is that the type of compound forms at the interface can be controlled by adjusting the Zn concentration of the Sn-based solders.

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9

Yang, Ling Mei, Peng Mei Lv, Zhen Hong Yuan, Wen Luo, Zhong Ming Wang e Hui Wen Li. "Promoting Effect of Metal Promoters on Fe(II)-Zn-Based Double Metal Cyanide Complex Catalysts for Biodiesel Synthesis". Advanced Materials Research 236-238 (maio de 2011): 3041–45. http://dx.doi.org/10.4028/www.scientific.net/amr.236-238.3041.

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Fe(II)-Zn-based double metal cyanide complex catalysts modified with rare earth metal or transition metal promoters(lanthanum, cerium, zirconium, manganese) for the production of biodiesel were prepared, and the effect of the addition of different metal promoters on the characteristics of the catalyst was studied by using X-ray diffraction (XRD), BET, ICP and Infrared techniques .The experiment results show that the Fe(II)-Zn-based catalyst promoted with 1 wt.% of La(NO3)3·nH2O exhibits the highest catalytic activity for the reaction, being as high as 99.3% of the yield of fatty acid methyl esters (FAME). Fe(II)-Zn-based catalysts have a tentative molecular formula: K2Zn3[Fe(CN)6]2·xH2O· (t-BuOH), where x=3-9 determined by using elemental analysis and ICP. It has been shown that the molecular formula of Fe(II)-Zn-based double metal cyanide complex catalysts did not change by adding 1 wt.% of rare earth metal or transition metal promoters. X-ray diffraction and BET results showed that Fe(II)-Zn-based catalysts with 1 wt.% of metal promoters salts exhibit smaller particle size, higher surface area than the Fe(II)-Zn catalyst ,which may be related to the higher activity of the catalysts.

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10

Yamauchi, Akira, e Masashi Kurose. "Effect of Sb and Zn Addition on the Microstructures and Tensile Properties of Sn–Bi-Based Alloys". Materials 15, n.º 3 (24 de janeiro de 2022): 884. http://dx.doi.org/10.3390/ma15030884.

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The tensile behavior of Sn–Bi–Cu and Sn–Bi–Ni alloys has been widely investigated. Reportedly, the addition of small amounts of a third element can refine the microstructures of the eutectic Sn-58mass% Bi solder and improve its ductility. However, the superplasticity mechanism of Sn-based alloys has not been clearly established. Therefore, in this study, the effects of Sb and Zn addition on the microstructures and tensile properties of Sn–Bi-based alloys were investigated. The alloys were subjected to tensile tests under various strain rates and temperatures. We found that Zn- and Sb-added Sn–Bi-based alloys demonstrated superplastic deformation at high temperatures and low strain rates. Sb addition significantly affected the elongation of the Sn–Bi–Sb alloys because the metal dissolves in both the primary Sn phase and the eutectic Sn–Bi matrix. The segregation of Zn and formation of needle-like Zn particles at the eutectic Sn–Bi phase boundary affected the superplastic deformation of the alloys. The deformation of the Sn–40Bi-based alloys at high temperatures and low strain rates led to dynamic recovery, dynamic recrystallization, and/or grain boundary slip because of the accumulation of voids.

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11

Huang, Yu-chih, e Sinn-wen Chen. "Co alloying and size effects on solidification and interfacial reactions in the Sn–Zn–(Co)/Cu couples". Journal of Materials Research 25, n.º 12 (dezembro de 2010): 2430–38. http://dx.doi.org/10.1557/jmr.2010.0314.

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Sn–Zn based alloys are promising as Pb-free solders, and Cu is commonly used in electronic products. Solidification and interfacial reactions of Sn–8.8wt%Zn, Sn–8.8wt%Zn–0.05wt%Co, and Sn–8.8wt%Zn–0.5wt%Co solders on Cu substrates are investigated. Two different masses of solders are used. The degrees of undercooling increase with increasing Co additions in the Sn–8.8wt%Zn alloys. The reaction products evolve with reaction time, and the timing of different reaction stages is influenced by both the minor Co alloying and the mass of solders. In the initial reaction stage, two reaction phases, γ-Cu5Zn8 and ε-CuZn5, are observed in the Sn–8.8wt%Zn/Cu and Sn–8.8wt%Zn-0.05wt%Co/Cu couples, and only the γ-Cu5Zn8 phase is found when the Co addition is up to 0.5 wt%. The reaction layers are thinner with higher Co alloying. The addition of Co into the Sn–Zn alloys consumes Zn, and this depletion of Zn in the Sn–Zn solders is the primary reason for the changes of reaction products and the thinner reaction layers.

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12

Chen, Fang, Yun Fei Du, Rong Chang Zeng, Gui Sheng Gan e Chang Hua Du. "Thermodynamics of Oxidation on Pb-Free Solders at Elevated Temperature". Materials Science Forum 610-613 (janeiro de 2009): 526–30. http://dx.doi.org/10.4028/www.scientific.net/msf.610-613.526.

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Based on the available thermodynamic and phase equilibria data, the thermodynamic criteria for oxidation in tin-based lead-free solders under soldering condition was deduced. The dependence of Gibbs free energy on temperature in Pb-free solder oxidation reaction was calculated by applying MATLAB program. The characteristics of oxidation reaction of a varity of solder alloy systems such as Sn-Ag, Sn-Cu, Sn-Sb, Sn-Zn, Sn-Ag-Cu and Sn-Pb eutectic alloys at elevated temperature were analyzed. The results suggested that zinc preferentially oxidized in Sn-Zn solder alloys in the elevated temperature state, while tin preferentially oxidized in the other alloys. The oxidation potential of the Sn-Zn eutectic alloys was higher than that of the pure tin at elevated temperature, whereas the oxidation potentials of Sn-Ag, Sn-Cu, Sn-Sb and Sn-Ag-Cu eutectic alloys were approxiately equal to that of the pure tin. All tin-based Pb-free solder alloys more easily oxidized than the Sn-Pb solder alloys. Oxidizability of these alloys followed in a decreasing order: Sn-Zn＞Sn-Sb＞Sn-Cu＞Sn-Ag＞Sn-Ag-Cu＞Sn-Pb.

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Tsurusaki, Tatsuya, e Takeshi Ohgai. "Mechanical Properties of Solder-Jointed Copper Rods with Electrodeposited Sn-Zn Alloy Films". Materials 13, n.º 6 (14 de março de 2020): 1330. http://dx.doi.org/10.3390/ma13061330.

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Enforced solid solution type Sn-Zn alloy films were electrochemically synthesized on Cu substrate from an aqueous solution containing citric acid complexes. The electrodeposition behavior of Sn-Zn alloys was classified to a normal co-deposition type, in which electrochemically nobler Sn deposits preferentially compared to Zn. Electrodeposited Sn-Zn alloy films were composed of a non-equilibrium phase, like an enforced solid solution, which was not observed in an equilibrium phase diagram of an Sn-Zn binary alloy system. By applying a thermal annealing process at 150 °C for 10 minutes, a pure Zn phase was precipitated from an electrodeposited Sn-based solid solution phase with excessively dissolved Zn atoms. During the soldering process, intermetallic phases such as Cu3Sn and Cu5Zn8 were formed at the interface between an Sn-Zn alloy and Cu substrate. Tensile strength and fracture elongation of solder-jointed Cu rods with Sn-8 at.%Zn alloy films reached ca. 40 MPa and 12%, respectively.

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Chou, Chin-yi, Sinn-wen Chen e Yee-shyi Chang. "Interfacial reactions in the Sn–9Zn–(xCu)/Cu and Sn–9Zn–(xCu)/Ni couples". Journal of Materials Research 21, n.º 7 (1 de julho de 2006): 1849–56. http://dx.doi.org/10.1557/jmr.2006.0229.

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Sn–Zn-based alloys are promising low melting-point Pb-free solders, and it has been reported that their wetting properties and oxidation resistance can be improved with the addition of Cu. The interfacial reactions in the Sn–9 wt% Zn–xCu/Cu couples at 250 °C and Sn–9 wt% Zn–xCu/Ni at 280 °C were examined in this study. A thick γ–Cu5Zn8 phase layer and a very thin β′–CuZn phase layer were formed in both the Sn–9 wt% Zn/Cu and the Sn–9 wt% Zn–1 wt% Cu/Cu couples. The γ–Ni5Zn21 phase layer was formed in both the Sn–9 wt% Zn/Ni and Sn–9 wt% Zn–1 wt% Cu/Ni couples. With longer reaction time, the δ–Ni3Sn4 phase were formed in the Sn–9 wt% Zn/Ni couple as well. In both the Cu and Ni couples, the Zn-containing γ phases were uniform and planar and were the dominant reaction products. However, when the Cu content of the Sn–9 wt% Zn–xCu solders was 10 wt%, the interfacial reaction product becomes the η–Cu6Sn5 phase in both the Cu and Ni couples.

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Yu, Chi-Yang, e Jenq-Gong Duh. "Stabilization of hexagonal Cu6(Sn,Zn)5 by minor Zn doping of Sn-based solder joints". Scripta Materialia 65, n.º 9 (novembro de 2011): 783–86. http://dx.doi.org/10.1016/j.scriptamat.2011.07.029.

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Katsman, A., e Menachem Bamberger. "Stabilization of Microstructures in Mg-Based Alloys: Modeling and Processing". Advanced Materials Research 95 (janeiro de 2010): 51–54. http://dx.doi.org/10.4028/www.scientific.net/amr.95.51.

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Extensive research work was devoted to Mg-based alloys strengthened by precipitation hardening. In this framework, the Mg-Zn-Sn system was considered a promising candidate for a creep resistant Mg-alloy. Small additions of alloying elements forming high temperature phases (HTP) were used to improve the structural stability of the Mg-Zn-Sn alloy. Phase formation during solidification was analyzed using thermodynamic calculations. The influence of HTP-particles on stabilization of sub-grain boundary structure was found to be of great importance in improving structural stability of the alloys at elevated temperatures. Mechanisms of precipitation hardening were investigated using the modified Langer-Schwartz model calibrated for Mg-Zn-Sn alloys.

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Huang, Chia-Wei, e Kwang-Lung Lin. "Interfacial reactions of lead-free Sn–Zn based solders on Cu and Cu plated electroless Ni–P/Au layer under aging at 150 °C". Journal of Materials Research 19, n.º 12 (1 de dezembro de 2004): 3560–68. http://dx.doi.org/10.1557/jmr.2004.0458.

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The interfacial reactions of Sn–Zn based solder on Cu and Cu/Ni–P/Cu–plating substrates under aging at 150 °C were investigated in this study. The compositions of solders investigated were Sn–9Zn, Sn–8.55Zn–0.45Al, and Sn–8.55Zn–0.45Al–0.5Ag solders in weight percent. The experimental results indicated that the Cu substrate formed Cu5Zn8 with the Sn–9Zn solder and Al–Cu–Zn compound with Al–containing solders. However, it was detected that Cu6Sn5 formed at the Sn–9Zn/Cu interface and Cu5Zn8 formed at the Al–containing solders/Cu interface after aging for 1000 h. When it contacted with the Cu/Ni–P/Au substrate, the Sn–9Zn solder formed Au–Zn compound, and the Al–containing solders formed Al–Cu–Zn compound at the interface. After a long aging time, the intermetallic compounds existing between solders and the Cu/Ni–P/Au metallization layers almost did not grow. It was found that the interdiffusion between solders and Cu/Ni–P/Au was slower than that with Cu under aging. Furthermore, the addition of Ag to Sn–Zn solder resulted in the formation of AgZn3 particles at the interface.

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Jabalameli, Mahin, Yahya Zamani, Sahar Baniyaghoob e Laleh Shirazi. "Study of Iron-Based Catalysts Performance in Fischer – Tropsch Synthesis: Temperature and Promoter Effect". Kataliz v promyshlennosti 23, n.º 1 (17 de janeiro de 2023): 56. http://dx.doi.org/10.18412/1816-0387-2023-1-56.

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The full text of the article will be published in the English version of the journal "Catalysis in Industry" No. 1, 2023.The iron-based catalysts were prepared via wet-impregnation method. The composition of the final iron catalysts, regarding to the weight ratio is as follow 14%Fe/γ-Al2O3, 14%Fe/3%Cu/γ-Al2O3, 14%Fe/3%Sn/γ-Al2O3 and 14%Fe/3%Cu/1%Sn/γ-Al2O3. The catalysts were characterized using XRD, ICP, BET, H2-TPR, FE-SEM and EDX techniques. The catalytic activity was evaluated in a fixed bed reactor under 20 bar of pressure, H2/CO = 1, GHSV = 2 L/(gcat·h), in the temperature range of 270–300 °C. Then, the effect of temperature and promoters (Cu and Sn) on the catalyst performance were investigated. CO conversion and product selectivity were also calculated using the results of GC. The results showed that the Cu and Sn promoters increased the reduction rate of Fe2O3 by providing H2 dissociation sites. Higher temperatures were also shown to change the CO conversion and product selectivity. The selectivity of both methane and C2–C4 hydrocarbons decreased while the selectivity of C5+ increased because of simultaneous use of Cu and Sn for promoting iron catalyst. Sn promoter increased FT and WGS activities.

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Luo, Qingcheng, Songbai Xue e Jie Wu. "Influences of Sn on Properties of Ag-Based and Cu-Based Brazing Filler Metals". Crystals 11, n.º 11 (18 de novembro de 2021): 1403. http://dx.doi.org/10.3390/cryst11111403.

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Ag-based and Cu-based brazing filler metals, which are the most widely used brazing materials in industrial manufacturing, have excellent gap-filling properties and can braze almost all the metallic materials and their alloys, except for the low-melting-point metals such as Al and Mg. Therefore, Ag-based and Cu-based brazing filler metals have attracted great attention. In this review, three series of typical Ag-based filler metals: the Ag-Cu, Ag-Cu-Zn, and Ag-Cu-Zn-Sn alloys; and three series of Cu-based filler metals: the crystalline and amorphous Cu-P filler metals, as well as the Cu-Zn filler metals, were chosen as the representatives. The latest research progress on Sn-containing Ag-based and Cu-based brazing filler metals is summarized, and the influences of Sn on the melting characteristics, wettability, microstructure, and mechanical properties of the selected filler metals are analyzed. Based on these, the problems and corresponding solutions in the investigation and application of the Sn-containing Ag-based and Cu-based filler metals are put forward, and the research and development trends of these filler metals are proposed.

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Fathy, N. "Interfacial Microstructure and Bonding Area of Sn-based Alloy-GG25 Gray Iron Bimetallic Material Using Flux, Sn, and Sn-Zn Interlayer Compound Casting". Engineering, Technology & Applied Science Research 12, n.º 2 (9 de abril de 2022): 8416–20. http://dx.doi.org/10.48084/etasr.4804.

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A bimetallic casting consisting of GG25 gray iron substrate and Sn-based alloy using the liquid-solid technique has been studied in this paper. Three different pretreatment processes of gray iron surface substrates including flux only, flux and Sn powder, and flux and Sn-8.8% Zn powder eutectic alloy surface treatment were adopted for the aim of improving the quality of tinning, the interfacial structure, and the bonding area of the Sn-based alloy/gray iron bimetallic composite in order to promote the bonding quality of bimetallic castings. Microstructure characterization on the bonding interface was conducted. The novel tinning material for gray cast iron substrate comprising of Sn-8.8% Zn eutectic alloy powder in combination with flux interlayer improved the bonding area, the interfacial bimetal structure, and the shear stress. This improvement is due to the higher interface reaction of Zn with Fe that leads to the formation of a very thin layer of Fe-Zn and Fe-Sn intermetallic phases.

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Wang, Fengyi, Xinjie Wang, Ziwen Lv, Chunjin Hang, Hongtao Chen e Mingyu Li. "A novel antioxidant and low-temperature Sn-Zn solder paste based on Zn@Sn core-shell structure". Materials Today Communications 31 (junho de 2022): 103356. http://dx.doi.org/10.1016/j.mtcomm.2022.103356.

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Azizan, Farihan M., Hadi Purwanto e Mohd Yusry Mustafa. "Effect of Sn Addition on Mechanical Properties of Zinc-Based Alloy". Advanced Materials Research 576 (outubro de 2012): 378–81. http://dx.doi.org/10.4028/www.scientific.net/amr.576.378.

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Zinc-based alloy is developed as an alternative alloy for giftware material. However, zinc alloy has limitation such as its mechanical properties. Therefore, modifying the properties of zinc based alloy is needed to use it for giftware material. The effect of adding Sn on the mechanical properties and fractography of Zn alloys are investigated. The results indicate that adding 15 wt. % of Sn has significant effect on the improving of tensile strength and elongation of the zinc based alloy due to the formation of AgSn phase. The fracture surface of the tensile test specimen showed a mixed mode of fracture exhibiting ductile failure and brittle failure. Alloy with Sn content up to 15 % tends to have more ductile failure then the brittle one. The alloys of Zn-0.50Ag-15Sn have very good tensile strength and elongation, which are better than Zn-0.50Ag-1Sn and Zn-0.50Ag-7Sn alloys.

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Yamaguchi, Masahiko, Tetsu Ichitsubo, Eiichiro Matsubara, Hisamichi Kimura, Kenichiro Sasamori, Hisao Irie, Seishi Kumamoto e Takaaki Anada. "Atomizing Effect on Sn-Zn Based Solder Alloy". Journal of the Japan Institute of Metals 70, n.º 2 (2006): 162–65. http://dx.doi.org/10.2320/jinstmet.70.162.

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Odusote, Yisau A., Adewumi I. Popoola, Kayode D. Adedayo e Samuel T. Ogunjo. "Thermodynamic properties of Al in ternary lead-free solder Al-Sn-Zn alloys". Materials Science-Poland 35, n.º 3 (20 de outubro de 2017): 583–93. http://dx.doi.org/10.1515/msp-2017-0080.

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AbstractThermodynamic properties of Al were calculated using the molecular interaction volume model (MIVM) by analyzing the activities of components in the constitutive binary Al-Sn, Al-Zn and Sn-Zn subsystems of the ternary lead-free solder Al-Sn-Zn systems. The activities of Al content in the ternary system at three cross-sections with constant molar ratios of Sn:Zn = 2:1, 1:1 and 1:2, respectively, were calculated and compared with available experimental data at 973 K. Based on the agreement between the calculated activity values and corresponding literature data for Al-Sn-Zn alloys and their subsystems, the activity of Al content in the ternary Al-Sn-Zn system was estimated at the same cross-sections and mole ratios in the temperature range of 1073 K to 1373 K, respectively. It has been observed through the computed activity values of Al that the thermodynamic properties of the ternary Al-Sn-Zn systems do not change appreciably with temperature across the molar sections.

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Ervina, Efzan M. N., e S. Y. Tan. "Wettability of Molten Sn-Zn-Bi Solder on Cu Substrate Ervina Efzan". Applied Mechanics and Materials 315 (abril de 2013): 675–80. http://dx.doi.org/10.4028/www.scientific.net/amm.315.675.

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This work presents the studies of wettability Sn-6Zn-4Bi lead-free solder alloy in electronic applications. A reference solder Sn-3.1Ag-0.9 Cu lead-free solder alloy is used to compare the properties of both solders. Differential Scanning Calorimeter (DSC) profile, wettability and the microstructure of the solder were investigated. The melting temperature of Sn-Zn-Bi (Tm=194.97°C) is lower than Sn-Ag-Cu (Tm=220.40°C). Further, the wettability between molten solder and copper substrate was measured at different reflow temperature. The contact angle for Sn-Ag-Cu was decreasing from 28.23º to 24.97º and for Sn-Zn-Bi solder alloys were decreasing from 48.92º to 29.78º as the temperature increased from 230°C to 250°C. A significant increment of contact angle for Sn-Zn-Bi at 270°C and the contact angle did not change at 270°C for Sn-Ag-Cu. The result of spreading area is inversed with the contact angle. The layers of intermetallic compound were examined by energy-dispersive X-ray. The Sn-Zn-Bi solder exhibits a mixture of Cu-Sn+Cu-Zn phase and ϒ-Cu5Zn8phase. The Sn-Ag-Cu solder exhibits Cu6Sn5 (η-phase) and Cu3Sn (ε-phase). As a conclusion, Sn-Zn-Bi is a potential lead-free solder to develop based on its wettability properties than previous available solder materials.

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Alam, S. N., Prerna Mishra e Rajnish Kumar. "Effect of Ag on Sn–Cu and Sn–Zn lead free solders". Materials Science-Poland 33, n.º 2 (1 de junho de 2015): 317–30. http://dx.doi.org/10.1515/msp-2015-0048.

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AbstractLead and lead-containing compounds are considered as toxic substances due to their detrimental effect on the environment. Sn-based soldering systems, like Sn-Cu and Sn-Zn are considered as the most promising candidates to replace the eutectic Sn-Pb solder compared to other solders because of their low melting temperature and favorable properties. Eutectic Sn-0.7 wt.% Cu and near eutectic composition Sn-8 wt.% Zn solders have been considered here for study. For the Sn-Cu system, besides the eutectic Sn-0.7 wt.% Cu composition, Sn-1Cu and Sn-2Cu were studied. Three compositions containing Ag: Sn-2Ag-0.7Cu, Sn-2.5Ag-0.7Cu and Sn-4.5Ag-0.7Cu were also developed. Ag was added to the eutectic Sn-0.7 wt.% Cu composition in order to reduce the melting temperature of the eutectic alloy and to enhance the mechanical properties. For the Sn-Zn system, besides the Sn-8 wt.% Zn near eutectic composition, Sn-8Zn-0.05Ag, Sn-8Zn-0.1Ag and Sn-8Zn-0.2Ag solder alloys were developed. The structure and morphology of the solder alloys were analyzed using a scanning electron microscope (SEM), filed emission scanning electron microscope (FESEM), electron diffraction X-ray spectroscopy (EDX) and X-ray diffraction (XRD). Thermal analysis of the alloys was also done using a differential scanning calorimeter (DSC). Trace additions of Ag have been found to significantly reduce the melting temperature of the Sn-0.7 wt.% Cu and Sn-8 wt.% Zn alloys.

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Kania, Henryk. "Corrosion Rate of Steel in Liquid Zn, Zn-Bi and Zn-Sn Baths". Coatings 13, n.º 6 (26 de maio de 2023): 993. http://dx.doi.org/10.3390/coatings13060993.

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In the hot dip galvanizing process, steel products are immersed in a liquid zinc bath. The contact of steel with liquid zinc causes the corrosion of the steel as a result of Fe dissolution processes in the liquid. If the dissolution process is carried out in a controlled manner, it results in the formation of a coating. Uncontrolled dissolution leads to the degradation of the steel surface. This article presents the results of research into the influence of Bi and Sn additions to zinc baths on the corrosion of steel in liquid zinc. Corrosion tests were carried out under conditions of kinetic dissolution using the rotating disc method. The kinetic dissolution constants of steel with different Si contents in Zn, Zn-0.5Bi and Zn-2Sn baths were determined. It was found that the addition of Bi and Sn lowers the value of the dissolution constant and may act as an inhibitor of Fe dissolution in liquid zinc. Based on the measurements and the determined value of the dissolution constant, the activation energy of kinetic dissolution was determined. It was found that in the temperature range of 440–480 °C, the addition of Bi and Sn increases the value of dissolution activation energy, which reduces the intensity of Fe transfer to the zinc bath.

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Li, Sijin, Junxian Zhu, Huiling Zhou, Mingqing Liao, Fengjiang Wang e Jian Chen. "Effects of Minor Zn Dopants in Sn-10Bi Solder on Interfacial Reaction and Shear Properties of Solder on Ni/Au Surface Finish". Materials 17, n.º 17 (3 de setembro de 2024): 4364. http://dx.doi.org/10.3390/ma17174364.

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Sn-10Bi low-bismuth-content solder alloy provides a potential alternative to the currently used Sn-Ag-Cu series due to its lower cost, excellent ductility, and strengthening resulting from the Bi solid solution and precipitation. This study primarily investigates the interfacial evolution and shear strength characteristics of Sn-10Bi joints on a Ni/Au surface finish during the as-soldered and subsequent isothermal aging processes. To improve the joint performance, a 0.2 or 0.5 wt.% dopant of Zn was incorporated into Sn-10Bi solder. The findings demonstrated that a 0.2 or 0.5 wt.% Zn dopant altered the composition of the intermetallic compound (IMC) formed at the interface between the solder and Ni/Au surface finish from Ni3Sn4 to Ni3(Sn, Zn)4. The occurrence of this transformation is attributed to the diffusion of Zn atoms into the Ni3Sn4 lattice, resulting in the substitution of a portion of the Sn atoms by Zn atoms, thereby forming the Ni3(Sn, Zn)4 IMC during the soldering process, which was also verified by calculations based on first principles. Furthermore, a 0.2 or 0.5 wt.% Zn dopant in Sn-10Bi significantly inhibited the Ni3(Sn, Zn)4 growth after both the soldering and thermal aging processes. Zn addition can enhance the shear strength of solder joints irrespective of the as-soldered or aging condition. The fracture mode was determined by the aging durations—with the brittle mode occurring for as-soldered joints, the ductile mode occurring for aged joints after 10 days, and again the brittle mode for joints after 40 days of aging.

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Yin, Li Meng, Jian Wei Xian e Zong Xiang Yao. "Comparison of Wettability for Sn-Based Solders on Copper and Aluminum Substrates". Materials Science Forum 687 (junho de 2011): 15–20. http://dx.doi.org/10.4028/www.scientific.net/msf.687.15.

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The wetting properties of four typical Sn-based solders, i.e., Sn-37Pb, Sn-3.0Ag-0.5Cu, Sn-0.7Cu and Sn-9Zn, on copper (Cu) and aluminum (Al) substrates at 250 °C, 260 °C and 270 °C were evaluated and compared by wetting balance method. The experimental results show that the wetting time of all solders on Cu substrate is shorter than that on Al substrate, but the wetting force of the solders with Cu substrate is bigger than that with Al substrate except Sn-9Zn solder. In addition, the wettability of the solders on Al substrate increases with increasing soldering temperature, and the wetting force of Sn-9Zn increases most obviously among four solders and reach 3.68 mN at 270 °C. The results also show that the wettability of the solders on Cu substrate mainly depends on surface tension of solder alloy, however, it depends on both surface tension and interaction with Al on Al substrate. Due to the active element Zn riches on the surface of Sn-9Zn solder, and Zn solid solutes into Al more easily, the wettability of Sn-9Zn solder on Al substrate is better than other three solders.

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Gorny, Anton, e Alexander Katsman. "Precipitation- and stress-influenced coarsening in Mg-based Mg–Zn–Sn–Y and Mg–Zn–Sn–Sb alloys". Journal of Materials Research 23, n.º 5 (maio de 2008): 1228–36. http://dx.doi.org/10.1557/jmr.2008.0166.

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Extensive experimental research work has been carried out to investigate precipitation peculiarities in Mg–Zn–Sn-based alloys during aging at different temperatures. This in-depth research was conducted on Mg–4.4wt%Zn–4.0wt%Sn–0.6wt%Y and Mg–4.4wt%Zn–4.4wt%Sn–1.1wt%Sb using x-ray diffraction (XRD), transmission electron microscopy (TEM) including high-resolution TEM, and scanning electron microscopy (SEM) equipped with an energy-dispersive x-ray spectrometer (EDS). It was found that, first, a hexagonal close-packed (hcp)-MgZn2 phase nucleates and grows in the form of needles having coherent interphase boundaries with α-Mg matrix. Then the face-centered cubic (fcc)-Mg2Sn-phase nucleates heterogeneously, mainly at the tips of MgZn2 needles. A very certain mutual orientation of crystal lattices of MgZn2, Mg2Sn, and α-Mg matrix was revealed. The orientation of Mg2Sn precipitates is perpendicular to that of MgZn2 needles. They grow in the form of plates parallel to the basal planes of α-Mg matrix. Two-phase T-like particles are very typical of alloys aged for 1 to 16 days at 175 to 225 °C. The width/length ratio of MgZn2 needles inside T-like particles differs substantially from that found in single needles. The elastic/surface energy balance of needles and its influence on the morphology and coarsening behavior has been analyzed.

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Isa, M. C., M. Y. Ahmad, Abdul Razak Daud e M. Daud. "The Effect of Sn on the Impedance Behaviour of Al-Zn Alloys in Natural Chloride Solution". Key Engineering Materials 442 (junho de 2010): 322–29. http://dx.doi.org/10.4028/www.scientific.net/kem.442.322.

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Electrochemical behaviour of cast Al-Zn alloys in natural chloride solution were investigated by potentiodynamic measurements and electrochemical impedance spectroscopy (EIS). Results from open circuit potential (OCP) measurement against immersion time showed a stable free corrosion process was achieved after 15 kiloseconds and alloys with more Sn contents had shifted OCP value towards more negative direction. Potentiodynamic polarisation curves showed that the corrosion potential (Ecorr) of aluminium alloys with Sn addition were much active compared to alloy without Sn. The anodic curves were characterized by no sign of passive current due active dissolution on the surface of the Al-Zn-Sn alloy. SEM images show that the presence of Sn in Al-Zn alloys produces better and uniform dissolution morphology. EIS results confirm that the presence of Sn is beneficial in improving anodic dissolution of Al-Zn alloys by reducing resistance to polarization (Rp). The presence of 0.1%wt. Sn in Al-Zn alloy has been found to be useful in activating electrochemical reaction at alloy-solution interface based on inductive loop in EIS diagram.

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Зерница, Денис Александрович. "CRYSTALLIZATION OF LEAD-FREE BINARY TIN-ZINC ALLOYS PRODUCED BY THE METHOD OF RAPIDLY SOLIDIFICATION FROM THE MELT". Physical and Chemical Aspects of the Study of Clusters, Nanostructures and Nanomaterials, n.º 14 (15 de dezembro de 2022): 92–100. http://dx.doi.org/10.26456/pcascnn/2022.14.092.

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Представлены результаты исследований структур быстрозатвердевших фольг сплавов системы Sn - Zn с низким содержанием легирующих элементов (до ~ 1,5 мас.%), сплавы околоэвтектических составов, а также сплавы, содержание легирующих элементов которых составляет 20-95 мас.%. В быстрозатвердевших сплавах, содержащих 1,5 мас.% Sn и 1,2 мас.% Zn, образуются пересыщенные твёрдые растворы, распадающиеся по механизму образования и роста зародышей новой фазы при комнатной температуре. Сплавы составами 4,4 - 15 мас.% Zn после высокоскоростного охлаждения являются переохлаждёнными и пересыщенными обоими компонентами, и испытывают спинодальный распад с последующим образованием пересыщенных твёрдых растворов на основе Sn и Zn, распадающиеся при комнатной температуре. Во всех остальных сплавах формируется двухфазная структура из твёрдых растворов на основе Sn и Zn. Выявлено, что по мере перемещения фронта кристаллизации от поверхности контактирующего слоя фольги с поверхностью кристаллизатора происходит укрупнение частиц Sn и уменьшение удельной поверхности межфазной границы. Установлено, что быстрозатвердевшие фольги имеют микрокристаллическую структуру зёрен, и при увеличении концентрации легирующих элементов наблюдается тенденция уменьшения размера зерна. The results of studies of the structures of rapidly solidified foils of alloys of the Sn - Zn system with a low content of alloying elements (up to ~1,5 wt.%), alloys of near-eutectic compositions, as well as alloys with an alloying element content of 20 - 95 wt.% are presented. In rapidly solidified alloys containing 1,5 wt. % Sn and 1,2 wt. % Zn, supersaturated solid solutions are formed, which decompose according to the mechanism of formation and growth of nuclei of a new phase at room temperature. Alloys (4,4 - 15 wt.% Zn) after rapidly solidification are supercooled and supersaturated with both components, and experience spinodal decomposition followed by the formation of supersaturated solid solutions based on Sn and Zn, which decompose at room temperature. In all other alloys, a two-phase structure is formed from solid solutions based on Sn and Zn. It was found that as the crystallization front moves from the surface of the contacting foil layer with the surface of the mold, the Sn particles coarsen and the specific surface of the interface decreases. It has been established that rapidly solidified foils have a microcrystalline grain structure, with an increase in the concentration of alloying elements, a tendency to a decrease in grain size is observed.

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Kim, Yong-Ho, Hyo-Sang Yoo e Hyeon-Taek Son. "Effects of Trace Elements on Thermal and Mechanical Properties of Al–Zn–Cu Based Alloys Using Extrusion". Journal of Nanoscience and Nanotechnology 20, n.º 7 (1 de julho de 2020): 4216–20. http://dx.doi.org/10.1166/jnn.2020.17543.

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Thermal properties and microstructure of Al-4 wt.% Zn-2 wt.% Cu–x (x = 2 wt%. Mg, 2 wt%. Sn, 0.7 wt.% Mg-0.7 wt.% Sn-0.7 wt.% Ca) alloys on cast and extrusion have been investigated with extrusion temperature of 400 °C. Al-4 wt.% Zn-2 wt.% Cu alloy was composed of Al and Al2Cu phases. By adding Mg contents, Al2Mg3Zn3 phase was increased and Al2Cu phase was decreased respectively. During hot extrusion, elongated in the extrusion direction because of severe deformation. The thermal conductivity with temperature and composition of as-extruded Al-4 wt.% Zn-2 wt.% Cu–x alloys decreases with adding 2 wt.% Mg, 2 wt.% Sn contents from 190.925 and 196.451 W/mK but thermal properties of addition of 0.7 wt.% Mg-0.7 wt.% Sn-0.7 wt.% Ca element slightly reduced from 222.32 to 180.775 W/mK. The ultimate tensile strength (UTS) for Al-4 wt.% Zn- 2 wt.% Cu alloy was 121.67 MPa. By adding 2 wt.% Mg contents, tensile strength was dramatically increased with 350.5 MPa.

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Wu, Jie, Songbai Xue, Zhen Yao e Weimin Long. "Study on Microstructure and Properties of 12Ag–Cu–Zn–Sn Cadmium-Free Filler Metals with Trace In Addition". Crystals 11, n.º 5 (16 de maio de 2021): 557. http://dx.doi.org/10.3390/cryst11050557.

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The effect of different In contents on the melting characteristics, mechanical properties, and microstructure of 12Ag–Cu–Zn–Sn filler metal was investigated in this paper, and flame brazing of 304 stainless steel and copper plates was done using the 12Ag–Cu–Zn–Sn–xIn filler metal. The results indicate that adding appropriate amount of In can evidently decrease the solidus and liquidus temperatures and improve the wettability of the low silver based filler metals. In addition, the shear strength of 304 stainless steel and copper plates joint brazed by 12Ag–Cu–Zn–Sn–1In are satisfactory due to the solution strength effect, and scanning electron microscopy examination of the braze-zone revealed that more relatively sound joints were obtained when brazing was done with 12Ag–Cu–Zn–Sn–xIn filler metal than with Indium free one; its performance is comparable to that of the joint brazed with the 20Ag–Cu–Zn–Sn filler metal, having a remarkable silver-saving effect.

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Kuo, Dong-Hau, e Bo-Jie Chang. "Growth Behaviors of ZnO Nanorods Grown with the Sn-Based Bilayer Catalyst-Covered Substrates". Journal of Nanomaterials 2011 (2011): 1–9. http://dx.doi.org/10.1155/2011/603098.

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The growth of ZnO nanorods performed at 700°C with the mixture of Zn and ZnO as the Zn source was investigated by having the catalysts in bilayer configurations of Sn (top)/Au (bottom), Sn/Al, Sn/Ni, and Sn/In. These catalyst layers were preannealed at 700°C or 850°C in a gas mixture of argon and hydrogen. The variations in the process parameters are to give the modulations in growing ZnO rods for the purpose of investigating the growth behaviors. The results show that the different compositions and configurations of bilayer catalysts can lead to different reactions and interdiffusions or in different kinetic performance, which will produce different sizes and states of catalyst templates for growing different sizes of the ZnO rods. The small-diameter ZnO nanorods with a hexagonal cross-section at the size of 70–150 nm were obtained from the Sn/Ni catalyst systems preannealed at 850°C.

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Ren, Xiaoyan, Huimin Chen, Yuan Chang, Ningning Chen, Zhenghua Shi, Yougui Zhang, Zhiming Guo e Jinzhi Hu. "Effect of Zn on Microstructure and Wear Resistance of Sn-Based Babbitt Alloy". Crystals 14, n.º 10 (19 de outubro de 2024): 907. http://dx.doi.org/10.3390/cryst14100907.

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Tin-based Babbitt alloys are a widely used bearing bushing material which have good comprehensive properties. However, problems such as high-temperature softening and insufficient bearing capacity occur during their use, so the optimization of tin-based Babbitt alloys has become a research hotspot. In this paper, ZChSnSb11-6 alloy was mainly prepared by the gravity casting method, and different amounts of Zn were added to the alloy (the mass fraction values were 0 wt.%, 0.05 wt.%, 0.1 wt.%, 0.15 wt.%, and 0.2 wt.%, respectively). Through the hardness test, the tensile test, the friction and wear test, and the microstructure observation of the prepared alloy, the influence of Zn on the organization and properties of the ZChSnSb11-6 alloy was analyzed. The results show that the size of the SnSb hard phase changed with the increasing content of Zn. The size of the hard phase of the SnSb tended to increase first and then decrease, and the number of phase particles increased first and then decreased, resulting in changes in performance. Through comparison, it was learned that the addition of Zn can effectively improve the hardness, tensile strength, yield strength, and wear resistance of the alloy, but the elongation rate was reduced. When the Zn content was 0.1 wt.%, the hardness value of the alloy reached the maximum value, 25.82 HB, which increased by 7.3% when compared with the sample without Zn. The hardness of the Zn, 0.15 wt.%, is close to that of the Zn, 0.1 wt.%. Compared to the sample without Zn, the tensile strength and elongation of the alloy were maximized at a Zn content of 0.15 wt.%. Compared to the sample without the Zn, the tensile strength was increased by 21.29%, and the elongation rate was increased by 46%. An analysis showed that the alloy has good comprehensive mechanical properties when the Zn content is 0.15 wt.%.

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Cheng, Ting, Jing Zhong e Lijun Zhang. "An Effective Strategy to Maintain the CALPHAD Atomic Mobility Database of Multicomponent Systems and Its Application to Hcp Mg–Al–Zn–Sn Alloys". Materials 15, n.º 1 (31 de dezembro de 2021): 283. http://dx.doi.org/10.3390/ma15010283.

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In this paper, a general and effective strategy was first developed to maintain the CALPHAD atomic mobility database of multicomponent systems, based on the pragmatic numerical method and freely accessible HitDIC software, and then applied to update the atomic mobility descriptions of the hcp Mg–Al–Zn, Mg–Al–Sn, and Mg–Al–Zn–Sn systems. A set of the self-consistent atomic mobility database of the hcp Mg–Al–Zn–Sn system was established following the new strategy presented. A comprehensive comparison between the model-predicted composition–distance profiles/inter-diffusivities in the hcp Mg–Al–Zn, Mg–Al–Sn, and Mg–Al–Zn–Sn systems from the presently updated atomic mobilities and those from the previous ones that used the traditional method indicated that significant improvement can be achieved utilizing the new strategy, especially in the cases with sufficient experimental composition–distance profiles and/or in higher-order systems. Furthermore, it is anticipated that the proposed strategy can serve as a standard for maintaining the CALPHAD atomic mobility database in different multicomponent systems.

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Phuong, Phan Que. "SYNTHESIS GLYCEROL CARBONATE FROM GLYCEROL AND URE USED SOLID ACID-BASE CATALYSTS BASED ON Zn-Al". Vietnam Journal of Science and Technology 56, n.º 3B (13 de setembro de 2018): 235. http://dx.doi.org/10.15625/2525-2518/56/3b/12897.

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In this study, we successfully synthesized Zn/Sn and Al/Sn catalysts by the combination of co-precipitation and hydrothermal methods.. These catalysts were prepared by hydrothermal method using zinc chloride ZnCl2, tin chloride SnCl4 and aluminium chloride AlCl3 precursors. Structure and physical properties of catalysts material were characterized by XRD, SEM. The products of glycerol conversion product was also tested by gas chromatography. The catalytic activity depends on reaction conditions (temperature and catalysts). The main product formed after the carbonylation reaction was glycerol carbonate. The selectivity of the main product was highest when using the Zn/Sn catalyst 5 % at a 145 °C during 5 hours with the yield was 77 %, the conversion degree was 88.5% and the selectivity was 86.91 %. For Al/Sn catalysts under the same reaction conditions, the efficiency was 61.3 % and the product selectivity achieved up to 74.05 % .

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Gogola, Peter, Zuzana Gabalcová, Martin Kusý e Henrich Suchánek. "The Effect of Sn Addition on Zn-Al-Mg Alloy; Part I: Microstructure and Phase Composition". Materials 14, n.º 18 (18 de setembro de 2021): 5404. http://dx.doi.org/10.3390/ma14185404.

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In this study, the addition of Sn on the microstructure of Zn 1.6 wt.% Al 1.6 wt.% Mg alloy was studied. Currently, the addition of Sn into Zn-Al-Mg based systems has not been investigated in detail. Both as-cast and annealed states were investigated. Phase transformation temperatures and phase composition was investigated via DSC, SEM and XRD techniques. The main phases identified in the studied alloys were η(Zn) and α(Al) solid solutions as well as Mg2Zn11, MgZn2 and Mg2Sn intermetallic phases. Addition of Sn enabled the formation of Mg2Sn phase at the expense of MgxZny phases, while the overall volume content of intermetallic phases is decreasing. Annealing did not change the phase composition in a significant way, but higher Sn content allowed more effective spheroidization and agglomeration of individual phase particles.

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Shan, Niu, Sun Chuan, Tang Bo-Wen, Yan Junjie, Sun Yu e Wang Shu. "Preparation and Superhydrophobicity of Sn Thin Film Based Zn Substrate". Integrated Ferroelectrics 199, n.º 1 (13 de junho de 2019): 52–57. http://dx.doi.org/10.1080/10584587.2019.1592597.

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Murashov, Vladimir, Boris B. Straumal e Pavel Protsenko. "Grain Boundary Wetting in Zn Bicrystals by a Sn-Based Melt". Defect and Diffusion Forum 249 (janeiro de 2006): 235–38. http://dx.doi.org/10.4028/www.scientific.net/ddf.249.235.

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The kinetics and morphology of the grain boundary grooving of Zn bicrystals with 16° <1010> tilt GB by Sn(Zn) melt has been studied at 325°C in equilibrium conditions in vacuum. It is shown that grooving process is interface controlled at least on the first stage. Groove walls mobility is evaluated. Changing of GB grove shape from “faceted walls” corner for annealing time < 78 h to concave “Mullins type” groove for annealing time > 78 h at the same experimental temperature was observed for the first time.

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Cheredova, T. V., S. G. Doroshkevich e S. V. Bartanova. "BEHAVIOR OF HEAVY METALS IN SOIL-CONDENSATE-PLANTS SYSTEM IN THE ULAN-UDE LANDFILLS". Геоэкология. Инженерная геология. Гидрогеология. Геокриология, n.º 1 (1 de janeiro de 2023): 50–58. http://dx.doi.org/10.31857/s0869780923010022.

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The impact of waste dumps on environmental components, i.e., soil, evaporating soil water (condensate) and plants is studied. It has been revealed that industrial and municipal waste dumps continue to affect significantly the environment after their closure. The behavior of heavy metals (Pb, Cu, Zn, Ni, Cd, Co, Sb, Sn, Bi, Hg, and Cr) in soils, plants, and condensate in landfill areas and beyond them (the background) has been studied in detail. It has been found out that soils, plants and condensate at landfills are enriched in heavy metals as compared to the background sites. The degree of soil contamination at waste dumps depends on the reclamation stage of the latter. The landfill soils exceed the norms of maximum permissible concentrations for heavy metals by 1.1–90 times. Concentrations of heavy metals in plants exceed the background values from 1.1 to 104 times at all dumps. The maximum level of heavy metals in plants is exceeded for Zn, Cd, Cr. In the condensate sampled at the dumps, MPC is exceeded for Cu, Zn, and Hg. Based on the analysis results, the geochemical rows of heavy metal distribution in different landfill environments were compiled: in plants – Zn Cu Cr Ni Pb Cd Co Hg Sn Bi; in condensate – Zn Cu Ni Cr Pb Sn Co Hg Sb Cd Bi; in the soil – Zn Cr Cu Ni Pb Co Sb = Sn Cd. The distribution of heavy metals in the condensate and plants is similar. In these environments, contribution of Zn and Cu is more than 80%, contribution of Cr, Ni, Pb varies from 1 to 10%; contribution of Cd, Co, Sb, Sn, Bi, Hg is less than 1%. Heavy metals are distributed in soil according to a different pattern: the main contributors are Zn and Cr (their input is more than 50%), then go Ni, Cu, Co, and Pb (their content in soil varies from 1 to 50%), followed by Sb, Sn, and Cd (their content is less than 1%). Total pollution indices (Zc) of the soil, condensate and plants have been calculated for each landfill. Based on Zc, the landfills were grouped in a ranking series, which can form the basis for assigning the sequence of landfill reclamation measures.

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Hernández, Daryl, Nicolás Jara, Mauricio Araya, Roberto E. Durán e Carlos Buil-Aranda. "PromoterLCNN: A Light CNN-Based Promoter Prediction and Classification Model". Genes 13, n.º 7 (23 de junho de 2022): 1126. http://dx.doi.org/10.3390/genes13071126.

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Promoter identification is a fundamental step in understanding bacterial gene regulation mechanisms. However, accurate and fast classification of bacterial promoters continues to be challenging. New methods based on deep convolutional networks have been applied to identify and classify bacterial promoters recognized by sigma (σ) factors and RNA polymerase subunits which increase affinity to specific DNA sequences to modulate transcription and respond to nutritional or environmental changes. This work presents a new multiclass promoter prediction model by using convolutional neural networks (CNNs), denoted as PromoterLCNN, which classifies Escherichia coli promoters into subclasses σ70, σ24, σ32, σ38, σ28, and σ54. We present a light, fast, and simple two-stage multiclass CNN architecture for promoter identification and classification. Training and testing were performed on a benchmark dataset, part of RegulonDB. Comparative performance of PromoterLCNN against other CNN-based classifiers using four parameters (Acc, Sn, Sp, MCC) resulted in similar or better performance than those that commonly use cascade architecture, reducing time by approximately 30–90% for training, prediction, and hyperparameter optimization without compromising classification quality.

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Shee, Nirmal Kumar, Min Kyoung Kim e Hee-Joon Kim. "Supramolecular Porphyrin Nanostructures Based on Coordination-Driven Self-Assembly and Their Visible Light Catalytic Degradation of Methylene Blue Dye". Nanomaterials 10, n.º 11 (22 de novembro de 2020): 2314. http://dx.doi.org/10.3390/nano10112314.

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A series of porphyrin triads (1–4), in which each triad is composed of a Sn(IV) porphyrin and two free-base (or Zn(II)) porphyrins, was synthesized and their self-assembled nanostructures were studied. Depending on the substituent on porphyrin moieties, each triad was self-assembled into a different nanostructure. In particular, the cooperative coordination of 3-pyridyl groups in the Sn(IV) porphyrin with the axial Zn(II) porphyrins in triad 4 leads to forming uniform nanofibers with an average width of 10–22 nm. Other triads without the coordinating interaction between the central Sn(IV) porphyrin and the axial porphyrins formed irregularly shaped aggregates in contrast. The morphologies of nanofiber changed drastically upon the addition of pyrrolidine, in which pyrrolidine molecules break down the self-assembly process by coordinating with the axial Zn(II) porphyrins. All porphyrin aggregates exhibited efficient photocatalytic performances on the degradation of methylene blue dye under visible light irradiation. The degradation efficiencies after 2 h were observed to be between 70% and 95% for the aggregates derived from the four triads.

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Bobkova, T. I., A. N. Beliakov, D. A. Gerashchenkov, E. Yu Gerashchenkova, A. F. Vasiliev e B. V. Farmakovsky. "Powdered composites of Al–Zn–Sn alloys for functional coatings". Voprosy Materialovedeniya, n.º 1(97) (10 de agosto de 2019): 79–84. http://dx.doi.org/10.22349/1994-6716-2019-97-1-79-84.

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The features of the process of obtaining a powder composition from an alloy based on the Al–Zn– Sn system are studied. A technology has been developed for obtaining powders of optimal composition, including Al; 6–11% Zn; 6–11% Sn; 2–4% Si; 0.6–0.8% Ce. Functional wear-resistant coatings recommended for practical use in products of precision and power engineering were made by supersonic cold gas dynamic spraying.

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Kumar, Vijay Bhooshan, Giora Kimmel, Ze'ev Porat e Aharon Gedanken. "Formation of particles of bismuth-based binary alloys and intermetallic compounds by ultrasonic cavitation". New Journal of Chemistry 39, n.º 7 (2015): 5374–81. http://dx.doi.org/10.1039/c5nj00781j.

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Xu, Xiao Yan, Guo Tong Qian, Jian Zhou, Yao Yao e Xu Chen. "Wettability of Sn-Zn Lead-Free Solder on Aluminum Substrate". Advanced Materials Research 815 (outubro de 2013): 48–54. http://dx.doi.org/10.4028/www.scientific.net/amr.815.48.

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The effects of flux components and compositions of solder alloys on the wettability of the Sn-Zn alloys on aluminum surface was investigated. The results show that the wettability of the Sn-9Zn solder on aluminum substrate improved with flux of double solvents composed of diethanolamine and triethanolamine, which is better than single solvent. When flux is composed of 3% zinc fluoborate as activator and 30% triethanolamine plus 67% diethanolamine as double solvents, the spreading area of the Sn-9Zn solder reaches to 75%. Trace addition (0.002%-0.005%) of Al results in significant improvement of the wettability of the Sn-9Zn based solder. However, additions of Bi or Sb are not beneficial to the wettability of the solder on aluminum substrate.

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Mayappan, Ramani, Nur Nadiah Zainal Abidin, Noor Asikin Ab Ghani, Iziana Yahya e Norlin Shuhaime. "Intermetallic Study on the Modified Sn-3.5Ag-1.0Cu-1.0Zn Lead Free Solder". Materials Science Forum 857 (maio de 2016): 3–7. http://dx.doi.org/10.4028/www.scientific.net/msf.857.3.

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Due to environmental concerns, lead-free solders were introduced to replace the lead-based solders in microelectronics devices technology. Although there are many lead-free solders available, the Sn-Ag-Cu solders are considered the best replacement due to their good wettability and joint strength. Although the Sn-Ag-Cu solders are accepted widely, but there are still some room for improvement. In this study, 1wt% Zn, which can be considered high percentage for a dopant, was added into the solder via powder metallurgy route. The effects of adding this dopant into the Sn-3.5Ag-1.0Cu solder on the interface intermetallic and thickness were investigated. The intermetallics phases formed were observed under Scanning Electron Microscope (SEM) and their thicknesses were measured. The SEM results showed the presence of Cu6Sn5, Cu3Sn and (Cu,Zn)6Sn5 intermetallics. It can be concluded that Zn behaved as retarding agent and significantly retarded the growth of Cu-Sn intermetallics.

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Mohd Rasid, Zarrul Azwan, Mohd Hafiz Zainol, Mohd Firdaus Omar, Mohd Nazree Derman e Muhammad Firdaus Mohd Nazeri. "Corrosion Performance of Sn-9Zn and Sn-0.7Cuin 3.5% NaCl Solution". Solid State Phenomena 273 (abril de 2018): 56–60. http://dx.doi.org/10.4028/www.scientific.net/ssp.273.56.

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Corrosion properties of Sn-9Zn and Sn-0.7Cu solder were investigated in 3.5 wt.% NaCl. The scanning rates used were fixed at 1.0mVs-1to study the effect of diffferent adding element which is Cu and Zn into the corrrosion properties of Sn-based solder. The morphological and structural properties of the samples were compared before and after the corrosion. The morphological analysis observed two types of corrosion product which is compacted and loosely-compacted corrosion product after the samples was polarized in 3.5% NaCl solution.

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Wang, Xiaotian, Mengxin Wu, Tie Yang e Rabah Khenata. "Effect of Zn doping on phase transition and electronic structures of Heusler-type Pd2Cr-based alloys: from normal to all-d-metal Heusler". RSC Advances 10, n.º 30 (2020): 17829–35. http://dx.doi.org/10.1039/d0ra02951c.

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By first-principles calculations, for Heusler alloys Pd₂CrZ (Z = Al, Ga, In, Tl, Si, Sn, P, As, Sb, Bi, Se, Te, Zn), the effect of Zn doping on their phase transition and electronic structure has been studied in this work.

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