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Perovskite solar cells (PSCs) employing formamidinium lead iodide (FAPbI3) have shown high efficiency. However, operational stability has been issued due to phase instability of α phase FAPbI3 at ambient temperature. Excess precursors in the perovskite precursor solution has been proposed to improve not only power conversion efficiency (PCE) but also device stability. Nevertheless, there is a controversial issue on the beneficial effect on PCE and/or stability between excess FAI and excess PbI2. We report here extended X-ray absorption fine structure (EXAFS) of FAPbI3 to study local structural change and explain the effect of excess precursors on photovoltaic performance and stability. Perovskite films prepared from the precursor solution with excess PbI2 shows better stability than those from the one with excess FAI, despite similar PCE. A rapid phase transition from α phase to non-perovskite δ phase is observed from the perovskite film formed by excess FAI. Furthermore, the (Pb-I) bond distance evaluated by the Pb LIII-edge EXAFS study is increased by excess FAI, which is responsible for the phase transition and poor device stability. This work can provide important insight into local structure-stability relation in the FAPbI3-based PSCs.

The development of highly stable and efficient oxide-based red phosphors is urgently required for next-generation lighting devices. Herein, we report the micro/crystal structures and luminescent properties of single-phase Eu2(WO4)3 and Eu3+-doped WO3-Eu2(WO4)3 composite phosphors prepared by a one-step conventional solid-state reaction method in air atmosphere. As increasing Eu contents in the mixtures of WO3 and Eu2O3, the intensities of the X-ray diffraction peaks of Eu2(WO4)3 increased while that of WO3 decreased. The photoluminescence intensity of the synthesized phosphors increased with increase in the Eu content when calcined at 900 °C, while it degraded at a higher temperature. Red-emitting single-phase Eu2(WO4)3 powders were successfully obtained when the WO3 and Eu2O3 powders were calcined in the ratio of 3:1. The intensity of the red emission spectra of the Eu2(WO4)3 phosphor was higher than those of the 6, 12, and 24 at.% Eu-added WO3 composites at excitation wavelengths of 394 and 465 nm. On the other hand, the intensity of emission from the single-phase phosphor was lower than that of the Eu-doped WO3-Eu2(WO4)3 composites under excitation of UV light at 254 nm. Thus, we propose two prospective phosphors for application as red phosphors at various wavelengths.

Ribosomal protein S3 (rpS3), a member of 40S small ribosomal subunit, is a multifunctional protein with various extra-ribosomal functions including DNA repair endonuclease activity and is secreted from cancer cells. Therefore, antibodies with high specificity against rpS3 protein could be useful cancer biomarkers. In this study, polyclonal antibody (pAb) and monoclonal antibodies (mAbs) were raised against rpS3 protein and epitope mapping was performed for each antibody; the amino acid residues of rpS3 were scanned from amino acid 185 to 243 through peptide scanning to reveal the epitopes of each mAb. Results showed that pAb R2 has an epitope from amino acid 203 to 230, mAb M7 has an epitope from amino acid 213 to 221, and mAb M8 has an epitope from amino acid 197 to 219. Taken together, novel mAbs and pAb against rpS3 were raised and mapped against rpS3 with different specific epitopes.

DNA double-strand breaks (DSBs) are one of the most serious types of DNA damage. However, multiple repair pathways are present in cells to ensure rapid and appropriate repair of DSBs. Pathway selection depends on several factors including cell type, cell cycle phase, and damage severity. Ribosomal protein S3 (rpS3), a component of the 40S small ribosomal subunit, is a multi-functional protein primarily involved in protein synthesis. rpS3 is also involved in the mediation of various extra-ribosomal pathways, including DNA damage processing and the stress response. Here, we report that rpS3 is a novel negative regulator of non-homologous end joining (NHEJ)-mediated repair of DSBs. We found that rpS3 interacts with the Ku heterodimers of the DNA-dependent protein kinase (DNA-PK) complex and slows down NHEJ ligation reactions, ultimately triggering p53-dependent cell death following treatment with high-dose ionizing radiation. After DSB formation, DNA-PK phosphorylates rpS3, which consequently reduces the binding of rpS3 to the Ku complex. We hypothesized that rpS3 may play a role in DSB repair by repressing NHEJ, while inducing other repair pathways, and by initiating DSB-induced cell death in response to severe DNA damage.

Purpose: The low rate of recurrent appendicitis after initial nonsurgical management of complicated appendicitis supports the recently implemented strategy of omitting routine interval appendectomy. However, several reports have suggested an increased incidence rate of neoplasms in these patients. We aimed to identify the risk of neoplasms in the population undergoing interval appendectomy.Methods: This study retrospectively analyzed consecutive cases of appendicitis that were treated surgically between January 2014 and December 2018 at a single tertiary referral center. Patients were divided into 2 groups depending on whether they underwent immediate or interval appendectomy. Demographics and perioperative clinical and pathologic parameters were analyzed.Results: All 2,013 adults included in the study underwent surgical treatment because of an initial diagnosis of acute appendicitis. Of these, 5.5% (111 of 2,013) underwent interval appendectomy. Appendiceal neoplasm was identified on pathologic analysis in 36 cases (1.8%). The incidence of neoplasm in the interval group was 12.6% (14 of 111), which was significantly higher than that of the immediate group (1.2% [22 of 1,902], P < 0.001). Conclusion: The incidence rate of neoplasms was significantly higher in patients undergoing interval appendectomy.These findings should be considered when choosing treatment options after successful nonsurgical management of complicated appendicitis.

The reversibly stable formation and rupture processes of electrical percolative pathways in organic and inorganic insulating materials are essential prerequisites for operating non-volatile resistive memory devices. However, such resistive switching has not yet been reported for dynamically cross-linked polymers capable of intrinsic stretchability and self-healing. This is attributable to the uncontrollable interplay between the conducting filler and the polymer. Herein, we present the development of the self-healing, stretchable, and reconfigurable resistive random-access memory. The device was fabricated via the self-assembly of a silver-gradient nanocomposite bilayer which is capable of easily forming the metal-insulator-metal structure. To realize stable resistive switching in dynamic molecular networks, our device features the following properties: i) self-reconstruction of nanoscale conducting fillers in dynamic hydrogen bonding for self-healing and reconfiguration and ii) stronger interaction among the conducting fillers than with polymers for the formation of robust percolation paths. Based on these unique features, we successfully demonstrated stable data storage of cardiac signals, damage-reliable memory triggering system using a triboelectric energy-harvesting device, and touch sensing via pressure-induced resistive switching.

Translation is a costly, but inevitable, cell maintenance process. To reduce unnecessary ATP consumption in cells, a fine-tuning mechanism is needed for both ribosome biogenesis and translation. Previous studies have suggested that the ribosome functions as a hub for many cellular signals such as ribotoxic stress response, mammalian target of rapamycin (mTOR), and ribosomal S6 kinase (RSK) signaling. Therefore, we investigated the relationship between ribosomes and mitogen-activated protein kinase (MAPK) activation under ribotoxic stress conditions and found that the activation of c-Jun N-terminal kinases (JNKs) was suppressed by ribosomal protein knockdown but that of p38 was not. In addition, we found that JNK activation is driven by the association of inactive JNK in the 80S monosomes rather than the polysomes. Overall, these data suggest that the activation of JNKs by ribotoxic stress is attributable to 80S monosomes. These 80S monosomes are active ribosomes that are ready to initiate protein translation, rather than polysomes that are already acting ribosomes involved in translation elongation. [BMB Reports 2019; 52(8): 502-507]

The aim of this research is to evaluate the protecting performance of hybrid fiber-reinforced concrete against lateral forces such as explosives or flying objects. The objective of this research is to better prepare this concrete for use in the ready-mix concrete industry. Even though the fiber addition gives it strong mechanical properties, it also decreases workability due to the inefficient dispersion of fibers. Therefore, it has been difficult to apply to the ready-mix concrete plant’s mixing, delivery and on-site placement. The authors have developed a combined steel and polyaramid fiber that gives the favorable protection needed against high-impact forces and provides a suitable workability for the ready-mix concrete system. To evaluate the required performance, the hybrid fiber-reinforced concrete specimen was subjected to high-speed projectiles and had its workability and performance tested on a construction site of an established ready-mix concrete company. The hybrid fiber-reinforced concrete successfully provided the protection capabilities sought for the finished product and provided a workable-ready mix applicability.

Organic-inorganic halide perovskites receive great attention due to their superb optoelectronic properties such as high efficiency over 25% demonstrated on a glass-based solar cell. Since flexible optoelectronics are considered to be more beneficial to territorial and space applications than the rigid counterparts due to lightweight and bendable characteristics, flexible perovskite optoelectronics need to be developed. However, mechanical properties of perovskite films depending on compositions has not been studied. We report here on bending fracture behavior of the flexible perovskite films depending on the substitution ratio (x) in four different compositions of (FAPbI3)1-x(CsPbBr3)x, (FAPbI3)1-x(MAPbBr3)x, FA1-xCsxPbI3, and FA1-xMAxPbI3 (FA = formaminidinium). The spin-coated perovskite films on the indium-tin-oxide (ITO)-coated polyethylene naphthalate (PEN) substrates show different morphology depending on x and composition. At certain values of x, that is mixed cation and/or mixed anion, a wrinkled morphology is obtained with different amplitude and wavelength in the sinusoidal surface structure. Based on applied and critical strains, fracture energy and fracture toughness are estimated, where the mixed compositions with enhanced wrinkled morphology show an improved bending fracture behavior as compared to the pure FAPbI3 or MAPbBr3. The highest fracture energy of 186.2 J/m2 along with fracture toughness of 3.559 GPa∙(m1/2) is obtained from (FAPbI3)0.75(CsPbBr3)0.25 due to highly enhanced wrinkled morphology.

Eu3+-activated WO3-Eu2(WO4)3 luminescent composite thin films are grown on low-cost slide glass substrates by radio frequency sputtering and then annealing in an air atmosphere furnace. The films obtained by sputtering 12 at.% of Eu-added WO3 target afforded a two-phase composite structure comprising Eu-doped WO3 and Eu2(WO4)3 after annealing. The composite thin films annealed at 600 °C exhibited strong red emission after growing at room temperature compared to those annealed at 500 °C under the excitation of 254, 394, and 465 nm corresponding to ultraviolet, near-ultraviolet, and blue light, respectively. The thin films grown at low temperatures without annealing did not emit under ultraviolet light. The crystalline structure, surface morphology, and optical properties, such as transmittance and photoluminescence, of the films grown at 500 °C were almost similar to those of the thin films grown at room temperature when they were annealed at the same temperature. Pure WO3 thin films without Eu doping showed similar crystallization behavior under the same annealing conditions as Eu-added composite films; however, they did not exhibit photoluminescence properties. Our report on the integration of thin-film red phosphors on glass substrates is promising for the development of low-cost and large-area optical devices activated at various excitation wavelengths.

In this study, optical and structural properties of the thin films prepared using glancing angle deposition (GLAD) are investigated. Various glancing angles and substrate rotations are employed to control the columnar microstructure of the films. The results show that as the glancing angle increases, the column angle and the porosity of TiO2 films increase and the refractive index decreases, due to shadow effects. The optical anisotropy of tilted and zigzag microstructure TiO2 films have a large anisotropy and reaches a maximum at a glancing angle of 60°, while that of helical microstructure TiO2 film deposited at 60° with substrate rotation shows a very small anisotropy due to the symmetric structure. It is found that the optical anisotropy of TiO2 films deposited by GLAD can be controlled by modification of microstructure.

The fabrication of composites consisting of ferromagnetic and ferroelectric complex oxides is important for the development of versatile multifunctional electronic devices. Herein, 0–3 type ceramic (BiFeO3)1-x-(Y3Fe5O12)x (0 ≤ x ≤ 0.3) composites, comprising Y3Fe5O12 particles randomly dispersed in a BiFeO3 matrix, were synthesized via a solid-state reaction. Two phases, BiFeO3 and Y3Fe5O12, were observed without the formation of any secondary phases. With increasing Y3Fe5O12 content in the composites, the leakage current dramatically decreased while the magnetic moment increased. A sputter deposition technique was introduced to grow BiFeO3-Y3Fe5O12 composite thin films on (0 0 1)-oriented SrTiO3 substrates. The BiFeO3-Y3Fe5O12 thin films grown at 650 °C exhibited isotropic magnetic behavior with low magnetization, whereas the magnetic hysteresis loops of the annealed films revealed two distinct slopes. The portion of the steeper slope near the zero field originated from the soft magnetic Y3Fe5O12 and increased with higher annealing temperature. This new fabrication of BiFeO3-Y3Fe5O12 composite thin films is promising to the design of new electronic devices with multifunctional properties.

Helidecks are vital structures that act as a last exit in an emergency. They transport people and goods to and from ships and offshore plants. When designing the structure of a helideck, it is necessary to comply with loading conditions and design parameters specified in existing professional design standards and regulations. In the present study, finite element analysis (FEA) was conducted with regard to a steel helideck mounted on the upper deck of a ship considering the emergency landing of the helicopter. The superstructure and substructure were designed, and the influence of various design parameters was analyzed on the basis of the FEA results.

The experimental observation of the transformation of nanosized SAC (Sn3.0Ag0.5Cu) into bulk-sized SAC during the melting process involving a large melting-point depression, using DSC (differential scanning calorimetry) and the reflow test is documented. They manufactured the nanosized SAC in dielectric benzyl alcohol using the modified direct-current arc method. The nanoparticles were spherical in shape with a size distribution of 5–10 nm. Using DSC, the endothermic peaks were continuously measured twice without changing the nanosized SAC. During the initial measurement, they observed peaks at 133, 162 and 217°C. However, in the second cycle, they observed only one peak at 217°C, which indicates the SAC nanoparticles have been completely melted and changed into bulk-sized SAC in the first cycle. They first conducted a reflow test of the SAC nanoparticles suspended in benzyl alcohol including flux on a printed circuit board and a hot plate which are 170°C. It was observed that SAC nanoparticles were transformed into bulk-sized SAC during the melting process at 170°C in less than 3 min. After the melting process, they also observed the formation of thin-layer geometry of SAC with 100 nm and intermetallic Cu6Sn5 between the SAC thin layer and a copper plate on PCB.

Today, the online market is showing an increasing growth. Considering the online market is dependent on the visual aspect on screen, the appearance is more influential to the consumer than any other design elements. With a global connection of online market, it is possible to buy a product across different countries. However, considering the different characteristics of consumers, it may not be ideal to sell products in one form. Therefore, the study aims to identify what form is most preferred and how consumer characteristics are related to the preference. First, types of form were defined for the study: stereotypical form, pure metaphorical form and story-driven metaphorical form. An online experimental tool, called paired comparison was developed. Through a mechanical Turk platform, we recruited 177 respondents: 50 from Germany, 50 from the United States, and 77 from South Korea. The results indicate context-driven metaphorical form was most preferred. And no significant difference was identified between three types of form in terms of demographical variables such as age and gender.

Many studies have shown that organizational justice (OJ) is related to psychological determinants of employees&rsquo, physical and mental health in the workplace, and these health outcomes also lead to the psychological well-being (PW) of employees. Additionally, physical activity is one of the most important issues related to health in the workplace. This study compared the level of perceived OJ according to sociodemographic and lifestyle factors and examined the association between OJ and PW by regular exercise (hours per week) in Korean employees. This study used cross-sectional data obtained from 494 subjects in South Korea. Self-administered questionnaires comprising OJ, PW, and lifestyle factors (e.g., smoking, drinking, sleeping, and exercise) were completed by employees in April 2017. Multiple logistic regression analyses were conducted to estimate the association of procedural justice (PJ) and interactional justice (IJ) with the prevalence odds ratios and 95% confidence intervals of the high risk to PW. After the adjustment of sociodemographic characteristics and lifestyle factors, the main effects of PJ and IJ on the high risk to PW were significantly observed, and when these values were stratified by a regular exercise category, the lowest odds ratio was observed in a group that exercised for 1&ndash, 2 h (hours per week). Organizations must encourage trust and consideration between employees and supervisors and carry out efforts to improve their environment, such as making the decision-making process fairer and encouraging employees to exercise regularly. This intervention may help prevent a high risk to PW.

Objectives: The aim of this study was to examine the effects of home-based cognitive physico-occupational therapy(HBCPOT) on cognitive function, depression, and quality of life in dementia patients, using a cognitive impairment model. Methods: The data was analysed for Mini-Mental State Examination-Korean version (MMSE-KC) for assessing cognitive function, Quality of life-Alzheimer’s Disease (QOL-AD) and Geriatric Depression Scale (GDS) in 31 dementia patients who received home-based cognitive physico-occupational therapy for one hour once a week for 12 weeks by a trained occupational therapist at the Dementia Prevention and Management Center of Y-city during 20111-2013. Results: Among these 31 patients, 18(58.1%) were female, and 25(80.6%) had Alzheimer’s Disease. After HBCPOT, the mean scores of MMSE-KC and QOL-AD were significantly improved, but GDS score was not significantly decreased. Conclusions: It was suggested that HBCPOT was effective in improving cognitive function and quality of life. Key words: dementia, home-based cognitive occupational therapy program, cognitive function, quality of life, depression

Objectives: The aim of this study was to evaluate the relationship of occupational stress and psychosocial stress to health promotion behaviors depending on characteristics of female office workers and emotional labor workers for sales. Methods: A survey of 207 female service workers engaging in sales of cosmetics in major department stores and 149 females working in the offices of cosmetics companies was carried out using a self-administered questionnaire. Results: It showed a significant difference in job demand and insufficient job control which are sub-domains of stress. The percentage of emotional laborers exposed to a high risk of psychosocial stress was higher than office workers. In office workers, occupational stress stemmed from insufficient job control and low reward of work was significantly related to psychosocial stress. But in emotional labor workers, stress from job insecurity, and organizational system were added. The relevant factors that affect health promotion behaviors were type of occupational stress, psychosocial stress, marital status, educational level and working career. Conclusions: Occupational stress and psychosocial stress were closely associated with health promotion behaviors. It was suggested that the development of health promotion programs which reduce the stress in female office and emotional labor workers.

Background Many studies show that organizational justice (OJ) is related to psychological determinants of employee health. To prevent health problems related to OJ in Korean workplaces and to accurately measure OJ, we developed the Korean version of the Organizational Justice Questionnaire (K-OJQ) and assessed its validity and reliability. Methods A questionnaire draft of the K-OJQ was developed using back-translation methods, which was preliminary tested by 32 employees in Korea. Feedback was received and the K-OJQ was finalized. This study used data from 303 workers (172 males, 131 females) in Korea using the K-OJQ, job stress, and lifestyle questionnaires. Results Cronbach’s α coefficients of the internal consistency reliability was 0.92 for procedural justice and 0.94 for interactional justice. Factor analyses using SPSS 24 and Amos 23 extracted two expected factors, named procedural justice (7 items; range, 1.0–5.0) and interactional justice (6 items; range, 1.0–5.0) and showed a reliable fit (χ2 = 182; p = .000; GFI = .912; AGFI = .877; CFI = .965; RMSEA = .077). Furthermore, higher procedural justice and interactional justice levels were correlated with lower job demand (− 0.33; − 0.36), insufficient job control (− 0.36; − 0.41), interpersonal conflict (− 0.45; − 0.51), job insecurity (− 0.33; − 0.34), organizational system (− 0.64; − 0.64), and lack of reward (− 0.55; − 0.63). Conclusions The K-OJQ was objectively validated through statistical methods. Electronic supplementary material The online version of this article (10.1186/s40557-018-0238-8) contains supplementary material, which is available to authorized users.

To analyze the trends in molecular interaction between bovine α-LA (BLA) and oleic acid, we investigated the effects of pH and protein conformation on oleate binding to BLA and compared the order-of-magnitude differences in binding behavior. Both isothermal titration calorimetry (ITC) and surface plasmon resonance (SPR) were used. For the ITC experiments, a solution of holo- or apo-BLA was titrated with sodium oleate at pH 4.0 and 10.0 to look for protein surface charge effects. In the SPR experiments, BLA was immobilized on the chip surface and sodium oleate solutions at various pHs (4.0, 5.5, 7.0, 8.5 and 10.0) were injected. Binding stoichiometry of ca. 5.2 molecules of oleate per unit molecule of BLA was observed. apo-BLA at a lower pH (lower than the pI of α-LA) yielded stronger binding avidity and affinity, which indicated that electrostatic interactions between the basic residues and the negatively charged carboxyl groups may play a major role in the complexation, in addition to hydrophobic interactions. The complexes formed at pH 4.0 and 5.5 were relatively unstable and rapidly dissociated when exposed to pH 7.0. In summary, we propose that the complexation can be regarded as a very weak (or, transient) and multivalent binding, requiring both electrostatic and hydrophobic interactions, probably in series and also in a dynamic equilibrium.

We developed a rapid quantification method of Pu, Am, and Cm in low- and intermediate-level radioactive waste using TRU resin, alpha spectrometry, and thermal ionization mass spectrometry for radioactive waste disposal. In particular, we focused on the optimization of sample preparation methods for alpha spectrometry and mass spectrometry to reduce the analysis time. The optimized method used Am and Pu stripping solutions for micro-coprecipitation and showed good recovery and alpha spectrum resolution for alpha counting. In addition, appropriate selection of Pu elution solution decreased the sample preparation time for thermal ionization mass spectrometry measurements.

The perfect (111)-oriented PZT/CFO (CFO=CoFe2O4, Co0.8Fe2.2O4 and Co0.6Mn0.2Fe2.2O4) bilayer multiferroic thin films were grown on Pt(111)/Si substrate at 600 °C using pulsed laser deposition technique. The precision X-ray diffraction analysis (avoiding the shift of peak due to the sample misalignment) revealed that the CFO films on Pt(111)/Si substrate were under an out-of-plane contraction and deposition of PZT top layer led to more increase in the out-of-plane contraction, i.e. increase in the residual stresses. The PZT and CFO layers have significant effects on magnetic and ferroelectric properties of PZT/CFO bilayer films, respectively, leading to an enhanced in-plane magnetic anisotropy as well as increased and asymmetric polarization. The effect of composition of CFO layer on magnetic field-dependent polarization of PZT/CFO bilayer films was investigated by applying the magnetic field during P-E measurement. The polarization of PZT films were increased by applying the magnetic field as a result of strain transferred from magnetostrictive CFO underlayer. This increase in polarization for PZT/Co0.6Mn0.2Fe2.2O4 was higher than that for PZT/Co0.8Fe2.2O4 and both of them were significantly higher than that for PZT/CoFe2O4 bilayer film, which was discussed based on their magnetostriction properties.

Software Reliability Growth Models (SRGMs) are useful for determining the software release date or additional testing efforts by using software failure data. It is not appropriate for a SRGM to apply to all software. And besides a large number of SRGMs have already been proposed to estimate software reliability measures. Therefore selection of an optimal SRGM for use in a particular case has been an important issue. The existing methods for selecting a SRGM use the entire collected failure data. However, initial failure data may not affect the future failure occurrence and, in some cases, it results in the distorted result when evaluating the future failure. In this paper, we suggest a method for selecting a SRGM based on the evaluation goodness-of-fit using partial data. Our approach uses partial data except for inordinately unstable failure data in the entire failure data. We will find a portion of data used to select a SRGM through the comparison between the entire failure data and the partial failure data excluded the initial failure data with respect to the predictive ability of future failures. To justify our approach this paper shows that the predictive ability of future failures using partial data is more accurate than using the entire failure data with the real collected failure data.Keywords:Software Reliability, Software Reliability Growth Model, Model Selection Criteria, T-point

This study investigates the effects of nanoparticle size and temperature on the thermal conductivity enhancement ofwater-based alumina (Al 2 O 3 ) nanofluids, using the centrifuging method and relative centrifugal forces of differing magni-tude to produce nanofluids of three different particles without involving any dispersants or surfactants. We determined thecoupling dependency in thermal conductivity enhancement relative to nanoparticle size and temperature of the aluminananofluids and also experimentally showed that the effect of temperature on thermal conductivity is strongly dependenton nanoparticle size. Also, our experimental data presented that the effective medium theory models such as the Maxwellmodel and Hasselman and Johnson model are not sufficient to explain the thermal conductivity of nanofluids since theycannot account for the temperature- and size-dependent nature of water-based alumina nanofluids. Nomenclature a K : Kapitza radius [m]a p : Radius of particle [m]d : Mean particle diameter [m]d

The perfect (111)-oriented Co 0.8 Fe 2.2 O 4 thin films are grown on Pt(111)/Si substrate using pulsed laser deposition technique at substrate temperature of 600 °C and laser pulse rate of 5 and 10 Hz. The Fe K -edge X-ray absorption near edge structure analyses revealed that Fe in Co 0.8 Fe 2.2 O 4 films deposited at both 5 and 10 Hz exists in Fe 3 + state leading to the actual composition of Co 0.8 Fe 2.2 O 4 +δ . In order to study the effect of film thickness on the magnetic properties, the film thickness was increased by increase in the pulse rate as well as the time of deposition during pulsed laser deposition process. It was found that by increase of the film thickness, the saturation magnetization and squareness will be generally increased. In the films with same thickness, those which deposited at higher pulse rate have a higher coercivity. In the films deposited at same pulse rate (10 Hz) and different time of deposition, the saturation magnetization, coercivity, and squareness were increased by increasing the thickness, but the coercivity will be decreased with further increasing the thickness due to the relaxation of residual stresses.

\(\text {Co}_{\mathrm {0.8}_{-{x}}}\text {Mn}_{x} \text {Fe}_{\mathrm {2.2}}\text {O}_{\mathrm {4}} (\textit {x}~=~0-0.3)\) thin films were grown on Pt(111)/Si substrate by pulsed laser deposition technique at an oxygen pressure of 10 mTorr and substrate temperature of 600 °C. The films have a perfect (111) orientation and compacted nano-sized grain-feature surface morphology (50–80 nm). Mn substitution leads to an increase in lattice constant indicating the presence of Mn in Mn2+ state rather than Mn3+. The observed increase in magnetization with increasing Mn content could be attributed to the higher magnetic moment of Mn2+ than that of Co2+. In addition, the coercivity of the films decreased with increasing Mn content.