Multilayer thick-film structures based on spinel ceramics

2014 ◽  
Vol 92 (7/8) ◽  
pp. 822-826 ◽  
Author(s):  
Halyna Klym ◽  
Ivan Hadzaman ◽  
Adam Ingram ◽  
Oleh Shpotyuk

Temperature-sensitive thick films based on spinel-type semiconducting ceramics of different chemical composition Cu0.1Ni0.1Co1.6Mn1.2O4 (with p+-types of electrical conductivity), Cu0.1Ni0.8Co0.2Mn1.9O4 (with p-types of electrical conductivity), and their multilayers of p+-p and p-p+-p structures were fabricated and studied. These thick-film elements possess good electrophysical characteristics before and after long-term ageing test at 170 °C. It is shown that degradation processes connected with diffusion of metallic Ag into grain boundaries occur in one-layer p- and p+-conductive thick films. The p+-p structures were of high stability, the relative electrical drift being no more than 1%. Positron trapping processes in so-called “free” thick-film structures based on spinel-type Cu0.1Ni0.8Co0.2Mn1.9O4 ceramics are studied. It is shown that two-state positron trapping model is appropriate for an adequate description of changes caused by additional glass phase in these materials. The observed behaviour of defect-related component in the fit of the experimentally measured positron lifetime spectra for thick films in comparison with bulk ceramics testifies in favour of agglomeration of free volume entities during technological process.

2013 ◽  
Vol 200 ◽  
pp. 156-161 ◽  
Author(s):  
Halyna Klym ◽  
I. Hadzaman ◽  
O. Shpotyuk ◽  
Q. Fu ◽  
W. Luo ◽  
...  

Multilayered temperature/humidity sensitive thick-film p-i-p+ structures based on spinel-type semiconducting ceramics of different chemical composition Cu0.1Ni0.1Co1.6Mn1.2O4 (with p+-type of electrical conductivity), Cu0.1Ni0.8Co0.2Mn1.9O4 (with p-type of electrical conductivity) and magnesium aluminate i-type MgAl2O4 ceramics, as well as p-p+ and p-p+-p structures were fabricated and studied. Temperature-sensitive thick-film structures possess good electrophysical characteristics before and after long-term ageing test at 170 оС, the relative electrical drift being no more than 1 %. Increase of number of thick-film layers from two to three results in the improvement temperature sensitivity of thick-film structures. It is shown, that just prepared humidity-sensitive thick films in one-layered performance posses good linear dependence of electrical resistance from relative humidity without hysteresis in the range of 40-99 %. Losses of the sensitivity of these elements in time at the normal physical condition are connected with degradation process on contact area. The integrated spinel-type p-i-p+ thick-film structures show humidity-sensitivity within one-order change of electrical resistance and are stable in time. These structures are shown to be successfully applied for integrated environmental sensors.


2010 ◽  
Vol 117 (1) ◽  
pp. 234-237 ◽  
Author(s):  
I. Hadzaman ◽  
H. Klym ◽  
O. Shpotuyk ◽  
M. Brunner

2018 ◽  
Vol 31 (3) ◽  
pp. 20
Author(s):  
Sarmad M. M. Ali ◽  
Alia A.A. Shehab ◽  
Samir A. Maki

In this study, the ZnTe thin films were deposited on a glass substrate at a thickness of 400nm using vacuum evaporation technique (2×10-5mbar) at RT. Electrical conductivity and Hall effect measurements have been investigated as a function of variation of the doping ratios (3,5,7%) of the Cu element on the thin ZnTe films. The temperature range of (25-200°C) is to record the electrical conductivity values. The results of the films have two types of transport mechanisms of free carriers with two values of activation energy (Ea1, Ea2), expect 3% Cu. The activation energy (Ea1) increased from 29meV to 157meV before and after doping (Cu at 5%) respectively. The results of Hall effect measurements of ZnTe , ZnTe:Cu films show that all films were (p-type), the carrier concentration (1.1×1020 m-3) , Hall mobility (0.464m2/V.s) for pure ZnTe film, increases the carrier concentration (6.3×1021m-3) Hall mobility (2m2/V.s) for doping (Cu at 3%) film, but  decreases by increasing Cu concentration.


2020 ◽  
Vol 25 (4) ◽  
pp. 323-330
Author(s):  
E. S. Ovcharenko ◽  
V. V. Erichev ◽  
S. I. Risovannij ◽  
T. V. Aksenova ◽  
S. V. Melekhov ◽  
...  

Relevance. A long-term inflammation in the oral cavity, unreasonable treatment of periodontal patients with antibiotics cause imbalance between certain types of fungal-bacterial associations accompanied by oral dysbiosis and change of local immune status. So, development and application of new comprehensive diagnosis and treatment techniques in periodontal patients, use of products for correction of microbiota and local immunity are a current and a long-term task. Purpose is to optimize the comprehensive treatment protocol of inflammatory periodontal diseases by introducing probiotics and evaluation of oral microbiome and cytokine profile.Materials and methods. 140 patients were examined. Of these 60 patients had chronic generalized plaque-induced gingivitis and 60 patients suffered from moderate chronic generalized periodontitis. Bacterial and fungal microbiome was assessed and the host immune response was evaluated in all patients before and after the treatment. Half of the patients were treated conventionally and the other half were treated according to a modified scheme: probiotic “Bifidumbacterin Forte” was added.Results. A large number of yeast-like fungi Candida and commensal bacteria were detected in periodontal pockets of patients with chronic generalized plaque-induced gingivitis and moderate chronic generalized periodontitis. That correlates with a significant increase of pro-inflammatory cytokines (TNF-α, IL—8), decrease of concentration of INF-γ and increase of antiinflammatory cytokine IL-4.Conclusion. Changes in clinical, microbiological and immunological values during a modified combination therapy with a probiotic and during a conventional treatment demonstrated that effectiveness of treatment of chronic gingivitis and chronic periodontitis increased by 40% and 37% respectively.


2020 ◽  
Vol 54 (5) ◽  
pp. 15-22
Author(s):  
I.M. Larina ◽  
◽  
D.N. Kashirina ◽  
K.S. Kireev ◽  
A.I. Grigoriev ◽  
...  

We performed the first ever comparative analysis of modifications in the proteome, ionogram and some other blood plasma biochemical indices of 18 male cosmonauts (44 ± 6 years of age) before and after maiden or repeated long-term missions to the Russian segment of the International space station (ISS RS). Levels of proteins, substrates and ions as well as chemical components were measured using the LC-MS-based proteomics and routine biochemical techniques. A total of 256 to 281 indices were investigated with the methods of descriptive statistic, regression analysis, and access to bioinformatics resources. It was shown that blood indices recovery from the maiden and repeated missions reflects changes in the body systems and goes at a various speed. The results of measurements made prior to launch and on day 7 after landing are dependent on the number of missions. The bioinformatics techniques showed that after maiden missions both the mediator proteins of alkaline phosphatase (AP) and blood proteins with reliably changing concentrations are associated with the bio-processes including stress, metabolism and DNA reparation, apoptosis, catabolism and proteolysis. During early re-adaptation from repeated missions the AP level was affected by bone remodeling, phosphorylation, angiogenesis and coagulation cascade suggesting a distinct and urgent trigger of the processes of bone structure and mineralization.


2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 559-559
Author(s):  
Sara Freed ◽  
Briana Sprague ◽  
Lesley Ross

Abstract Interventions using exercise video games, or exergames, have shown short-term cognitive and physical benefits to older adults, though long-term effects are less promising. Enjoyment of exergames may promote exergame use after the intervention period, though little work has examined older adults’ views of exergames before and after gameplay experience. We invited 20 older adults between 65 and 84 years of age (M=73.30, SD=5.95) to play two Xbox Kinect games, Just Dance and Kinect Sports Rivals, for twenty minutes. In our presentation, we will present qualitative and quantitative findings of this pilot study, including findings that older adults reported that they were not likely to play similar exergames in the future and that they did not find the exergames to be more fun compared to other ways of exercising. We will discuss implications for game design and research relevant to game developers, manufacturers, and researchers. Part of a symposium sponsored by Technology and Aging Interest Group.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Xiaorong Yan ◽  
Huiqing Wang ◽  
Cai Li ◽  
Yuanxiang Lin ◽  
Lin Lin ◽  
...  

Abstract Background To present a surgical technique for the treatment of intradural extramedullary (IDEM) tumors by using endoscopically controlled surgery with open hemilaminectomy technique. Methods In this study, 20 patients with 22 IDEM tumors were enrolled. An endoscopically controlled surgery with open hemilaminectomy was employed to remove the tumors. Data related to clinical symptoms and medical images before and after surgery were collected for perioperative evaluation and follow-up analysis. Results All the tumors in 20 patients were well removed. The clinical symptoms were significantly reduced in all the patients as well. The short-term follow-up data showed that there was no tumor recurrence or spinal deformity. Conclusion The endoscopically controlled surgery with open hemilaminectomy technique provided favorable exposure and satisfactory resection to the IDEM tumors. It may be an effective surgical method for treating IDEM tumors. Larger samples and longer follow-up data are needed to verify its long-term effectiveness.


2021 ◽  
Vol 13 (15) ◽  
pp. 8316
Author(s):  
Camelia Mirela Baba ◽  
Constantin Duguleană ◽  
Marius Sorin Dincă ◽  
Liliana Duguleană ◽  
Gheorghița Dincă

The Covid-19 induced economic crisis has significantly affected almost all businesses from nearly every sector, causing severe financial problems, lack of cash assets, and decrease of revenues. In this context, the economic entities were forced to look for adjustment and rescue solutions of their activities. One possible solution for the recovery and reorganization of economic entities’ activities is demerger. This paper evaluates the impact of demerger upon the sustainable development of economic entities in terms of economic efficiency and financial performances. To achieve this goal, a statistical analysis of profitability ratios before and after the demerger, as well as a structural analysis of 268 demerger projects for the April 2012–April 2021 period, were performed. The results attest there are no significant differences between the ex-ante and ex-post financial performances. However, demerger seems to have a positive effect upon analyzed companies helping them to overcome economic hardships, rethink their business strategies, and continue their activity in the medium and long-term time horizon.


2021 ◽  
pp. jnnp-2021-326043
Author(s):  
Alis Heshmatollah ◽  
Lisanne J. Dommershuijsen ◽  
Lana Fani ◽  
Peter J. Koudstaal ◽  
M. Arfan Ikram ◽  
...  

ObjectiveAlthough knowledge on poststroke cognitive and functional decline is increasing, little is known about the possible decline of these functions before stroke. We determined the long-term trajectories of cognition and daily functioning before and after stroke.MethodsBetween 1990 and 2016, we repeatedly assessed cognition (Mini-Mental State Examination (MMSE), 15-Word Learning, Letter–Digit Substitution, Stroop, Verbal Fluency, Purdue Pegboard) and basic and instrumental activities of daily living (BADL and IADL) in 14 712 participants within the population-based Rotterdam Study. Incident stroke was assessed through continuous monitoring of medical records until 2018. We matched participants with incident stroke to stroke-free participants (1:3) based on sex and birth year. Trajectories of cognition and daily functioning of patients who had a stroke 10 years before and 10 years after stroke and the corresponding trajectories of stroke-free individuals were constructed using adjusted linear mixed effects models.ResultsDuring a mean follow-up of 12.5±6.8 years, a total of 1662 participants suffered a first-ever stroke. Patients who had a stroke deviated from stroke-free controls up to 10 years before stroke diagnosis in cognition and daily functioning. Significant deviations before stroke were seen in scores of MMSE (6.4 years), Stroop (5.7 years), Purdue Pegboard (3.8 years) and BADL and IADL (2.2 and 3.0 years, respectively).ConclusionPatients who had a stroke have steeper declines in cognition and daily functioning up to 10 years before their first-ever stroke compared with stroke-free individuals. Our findings suggest that accumulating intracerebral pathology already has a clinical impact before stroke.


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