9.4.8 Iron group metals

Author(s):  
G. V. Kidson
Keyword(s):  
1996 ◽  
Vol 451 ◽  
Author(s):  
T. P. Moffat

ABSTRACTA variety of Cu/(Ni, Co) multilayers have been grown on Cu single crystals by pulse plating from an alloy electroplating bath. Copper is deposited under mass transport control while the iron group metal is deposited under interfacial charge transfer control. The structural evolution of these films is influenced by the morphological instability of the mass transport limited copper deposition reaction and the development of growth twins during iron-group metal deposition. Specular films have been obtained for growth on Cu(100) while rough, defective films were typically obtained for growth on Cu(111) and Cu(110).


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Min Suk Chae ◽  
Mihyun Lee ◽  
Min Ho Choi ◽  
Je Uk Park ◽  
Misun Park ◽  
...  

Abstract Background Previous studies have reported the efficacy and safety of intravenous (IV) iron therapy during the perioperative period as an alternative and adjunct to allogeneic blood transfusion. Preemptive IV iron therapy provides noninferior hemoglobin levels on postoperative day (POD) 1 compared to autologous whole blood therapy (AWBT) in healthy patients who had undergone bimaxillary orthognathic surgery. Methods This was a prospective, patient-randomized, noninferiority trial. After excluding 2 patients, 64 patients were divided into two groups: the IV iron therapy group (patients received IV iron infusion 4 weeks before surgery; n = 32) and the AWBT group (2 units of autologous whole blood were collected 4 and 2 weeks before surgery; n = 32). The primary outcome was hemoglobin level on POD 1 and the prespecified noninferiority limit was − 1 g/dL. Results Baseline data were comparable, including hemoglobin and iron levels, between the two groups. Immediately before surgery, the levels of hemoglobin, iron, and ferritin were higher in the IV iron group than in the AWBT group. The mean treatment difference (iron group—whole blood group) in hemoglobin level on POD 1 between the two groups was 0.09 (95% CI = − 0.83 to 1.0). As the lower limit of the 95% CI (− 0.83) was higher than the prespecified noninferiority margin (δ = − 1), noninferiority was established. On POD 2, the hemoglobin level became lower in the iron group, which eventually led to greater requirement of allogeneic blood transfusion compared to the whole blood group. However, the iron group did not require allogeneic blood transfusion during or early after surgery, and the whole blood group showed continuously higher incidence of overt iron deficiency compared to the iron group. Conclusion As collection of autologous whole blood caused overt iron loss and anemia before surgery and intraoperative transfusion of whole blood was not able to prevent the occurrence of persistent iron deficiency after surgery, IV iron therapy was found to have potential benefits for iron homeostasis and subsequent erythropoiesis in healthy patients early after bimaxillary orthognathic surgery. Trial registration: Clinical Research Information Service, Republic of Korea, approval number: KCT0003680 on March 27, 2019. https://cris.nih.go.kr/cris/search/search_result_st01_kren.jsp?seq=15769&sLeft=2&ltype=my&rtype=my.


2003 ◽  
Vol 48 (7) ◽  
pp. 819-830 ◽  
Author(s):  
Daheum Kim ◽  
D.-Y. Park ◽  
B.Y. Yoo ◽  
P.T.A. Sumodjo ◽  
N.V. Myung

1965 ◽  
Vol 20 (12) ◽  
pp. 1648-1654 ◽  
Author(s):  
I. Broser ◽  
H.-E. Gumlich ◽  
R. Moser

The kinetics of holes in electroluminescence has been calculated by means of simple two- and three-level-models. As a result an equation is given which describes the ratio of intensity of different emission bands and the degree of luminescence quenching by iron group elements as a function of field frequency and temperature. The calculated curves are in good agreement with the values observed in ZnS containing Cu, Mn, Fe, Co, Ni respectively. The kinetics has been used to calculate the energetic separation of acceptor levels from the valence band and other constants.


1997 ◽  
Vol 491 ◽  
Author(s):  
Alexander Bratkovsky

ABSTRACTIn the present paper different tunneling mechanisms in conventional and half-metallic ferromagnetic tunnel junctions are analyzed within the same general method. Theoretically calculated direct tunneling in iron group systems leads to about a 30% change in resistance, which is close but lower than experimentally observed values. It is shown that the larger observed values of the TMR might be a result of tunneling involving surface polarized states. We find that tunneling via resonant defect states in the barrier radically decreases the TMR (down to 4% with Fe-based electrodes), and a resonant tunnel diode structure would give a TMR of about 8%. With regards to inelastic tunneling, magnons and phonons exhibit opposite effects: one-magnon emission generally results in spin mixing and, consequently, reduces the TMR, whereas phonons are shown to enhance the TMR. The inclusion of both magnons and phonons reasonably explains an unusual bias dependence of the TMR.The model presented here is applied qualitatively to half-metallics with 100% spin polarization, where one-magnon processes are suppressed and the change in resistance in the absence of spin-mixing on impurities may be arbitrarily large. Even in the case of imperfect magnetic configurations, the resistance change can be a few 1000 percent. Examples of half-metallic systems are CrO2/TiO2 and CrO2/RuO2, and an account of their peculiar band structures is presented. The implications and relation of these systems to CMR materials, which are nearly half-metallic, are discussed.


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