In internet service industries, such as competitive industries, it costs more to attract new consumers to become customers of the company than saving the consumers who already are customers. Therefore, detecting the running off customers and finding a way to keep the customers from leaving is extremely important. This study addresses the problem of customer attrition in the internet service industry by choosing the best-performing model to detect the customers who are going to run off in advance. To select the most suitable model for accurately detecting customer churn, this study performs preprocessing, including data cleaning, feature engineering, and feature selection. The dataset is then split into training, testing, and validation sets. Various models are built and evaluated based on their performance, measured by calculating the mean and standardized values of the detection rate. The result is that the Light Gradient Boosting Machine (LGBM) model has superior performance in detection rate scoring.
This paper employs the super-efficiency slack-based measure (SBM) model with undesirable outputs to measure the green development efficiency of the agricultural product circulation industry (APCI) across 26 provinces of China from 2013 to 2022, and applies the kernel density estimation method to reveal its spatio-temporal evolution characteristics. Furthermore, the Tobit model is utilized to analyze the factors influencing the green development efficiency of the APCI. The research reveals that: (1)The green development efficiency of China's APCI is at a medium level. In 2019, a significant spatial demarcation emerged in the green development efficiency of China's agricultural product circulation industry, with the efficiency highland shifting from North/Northeast China to Southern regions, thereby manifesting a new ''high-south, low-north'' efficiency configuration. (2) Interprovincial disparities initially narrowed and subsequently widened. Furthermore, the six major regions exhibited heterogeneous dynamic characteristics, while the green development efficiency of the APCI demonstrated spatial imbalance across provinces. (3) The openness to international market (OIM) exerts a statistically significant positive effect on the green development efficiency of the APCI. Conversely, industrial structure (IS) and agricultural pollution level (API) demonstrate inhibitory effects on APCI's green development efficiency. This study deepens the understanding of APCI's green development efficiency, constructs a systematic measurement framework, expands research perspectives, and provides tools for governments, industries, and enterprises to evaluate efficiency accurately.
This study shows an alkaline activated cement (AAC), also known as geopolymer, made from red brick waste with partial addition of Ordinary Portland Cement (OPC). This is a sustainable material since incorporates waste from the brick industry to make cements, therefore increasing the materials circularity and this reducing pollution. The material was cured at room temperature. The brick residue was activated with sodium hydroxide and sodium silicate in aqueous solution to form the hybrid cement. Several mixtures were made with different amounts of waste and proportions of alkaline activator. The mechanical properties of the materials were studied to determine their feasibility to be used in the construction sector. Three contents of OPC were used: 10, 20, and 30 wt%, which were added to improve the mechanical behavior and post-curing time. The activated hybrid cement was analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), compression, and flexural tests. The main results show that the addition of OPC to the brick derived AAC produces an increased compressive strength of 106 MPa when 30 wt% OPC was added, a very significant result since the control sample found was 33 MPa in compression strength, an improvement for more than 3 times. The data were corroborated by statistical analysis.
Sasirangan is a typical cloth from the South Kalimantan which is produced by the Banjarist people in home industries. The production of sasirangan has a very positive impact on the welfare of Banjarist people. However, the processing and liquid waste resulting from the production process can have a negative impact on workers' health and the environment because it contains synthetic dyes and heavy metals. This is caused by poor worker behavior in processing and disposing of liquid waste from sasirangan cloth. Worker behavior can be related to worker education and knowledge. This research aims to analyze the relationship between education, knowledge and the behavior of sasirangan workers in processing and disposing of waste in the home-based sasirangan industry in Banjarmasin. This research is an analytical observational study with a cross sectional approach, carried out at 3 (three) sasirangan production locations: Sungai Jingah, Seberang Masjid Village and Surgi Mufti subdistricts. Sampling used a purposive sampling technique with a sample size of 30 workers. Data analysis was carried out using descriptive and statistical analysis using the Chi Square test with the alternative Fisher Exact Test. The results of data analysis show the p value of the education variables (p=0.032) and knowledge (p=0.049). There is a significant relationship between education and knowledge and worker behavior in processing and disposing of waste in the sasirangan home industry in Banjarmasin. This is in accordance with Lawrence Green's theory, the better the worker's education and knowledge, the better the worker's behavior. The existence of a significant relationship between education and knowledge and workers' behavior in processing and disposing of waste in the sasirangan home industry in Banjarmasin requires follow-up in the form of efforts to increase education and knowledge regarding the processing and disposal of sasirangan waste for workers in the sasirangan home industry in Banjarmasin.
Dana Alshwayat, Hamzah Elrehail, Esam Shehadeh
et al.
The banking industry has undergone significant shifts as innovations have enabled new banking services and created new customer requirements. While banks strive to incorporate innovation and change systems, they also face various obstacles. The primary aim of this qualitative exploratory case study is to determine the key perceived barriers to change and innovation in a Jordanian commercial case bank from the perspective of senior management. Nuanced interpretations were investigated, resulting in new insights that have not been previously obtained from research in this field. The analysis used a qualitative systematic approach to grounded theory articulation that inductively generated new concepts while adhering to highly rigorous standards. The methodology was based on interviews with eight senior managers. The emergent findings revealed that high bureaucracy, lack of communication, lack of employee involvement, middle managers' resistance, and risk aversion were major barriers to innovation and change. Overall, this study contributes to developing a thorough understanding of top managers' perceptions of barriers to innovation and change and offers managers and practitioners guidance on improving organizational conditions to support innovation and change in the banking industry. Finally, this study provides avenues for future research in this area.
Pablo López-Porfiri, Sebastián Ramos-Paredes, Patricio Núñez
et al.
Abstract Membrane distillation (MD) is constantly acknowledged in the research literature as a promising technology for the future of desalination, with an increasing number of studies reported year after year. However, real MD applications still lag behind with only a few pilot-plant tests worldwide. The lack of technology transfer from academia to industry is caused by important gaps between its fundamental basis and the process design. Herein, we explore critical disconnections by conducting coupled mass and heat transfer modeling and MD simulations; we use well-known MD mass and heat transfer equations to model and simulate flux over a typical MD membrane for different geometries, areas, and operational conditions in direct contact configuration. From the analysis of the results, we propose research guidelines and process development strategies, and construct an MD module performance curve. From this graph, permeate flow rate, thermal energy consumption and outlet temperatures can be determined for given feed inlet conditions (temperature and concentration). Comprehensive tools such as this MD module curve and good communication between membrane developers and process engineers are required to accelerate the process of bringing the MD technology from a still-emerging status to a maturity level.
Work accidents have the ability to cause the formation of every work activity. Aspects of work accidents can be caused by machines or aspects of worker negligence. The comfort of workers is highly dependent on the situation and the industrial area. One of the markers that need to be observed is occupational safety and health. So that the industry applies the K3 listed on PT Swadaya Graha which is currently still in a non-HIRARC condition as a basis for mitigation. The HIRARC procedure finds a procedure that starts to ensure the activity after which the source of the hazard is identified, risk assessment, and control over that exists and has the aim of remembering the level of risk associated with a place. From that case, the author thinks it is necessary to carry out an OHS risk assessment using the HIRARC procedure by carrying out research that aims to find out how to analyze the capabilities of hazards that can be carried out and their control on a cnc lathe machine at PT Swadaya Graha . The procedure used is the HIRARC (Hazard Identification Risk Assessment and Risk control) approach. The results of this research are that there are 5 work disaster hazard capabilities in the Ministry of CNC BUBUT. After that this research shows there is no. 1. extreme type of hazard. risk, and 1 high risk and 3 medium risk. The most common hazard abilities occur because of the lack of PPE and the undisciplined workers and not exploring work SOPs. Therefore, it is necessary to try socialization and continue to emphasize through daily safety briefings and safety signs.
The porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most important pathogens causing substantial economic losses to the Chinese swine industry. In this study, we analyzed the complete genome sequences of four PRRSV isolates (PRRSV2/CN/SS0/2020, PRRSV2/CN/SS1/2021, PRRSV2/CN/L3/2021, and PRRSV2/CN/L4/2020) isolated from a single pig farm from 2020 to 2021. The genomes of the four isolates were 14,962–15,023 nt long, excluding the poly (A) tails. Comparative analysis of the genome sequences showed that the four isolates shared 93.2–98.1% homology and they had no close PRRSV relatives registered in the GenBank (<92%). Furthermore, PRRSV2/CN/SS0/2020 and PRRSV2/CN/SS1/2021 had characteristic 150-aa deletions (aa481+aa537-566 +aa628–747) that were identical to the live attenuated virus vaccine strain TJM-F92 (derived from the HP-PRRSV TJ). Further analysis of the full-length sequences suggests that the four isolates were natural recombinant strains between lineages 1 (NADC30-like), 3 (QYYZ-like), and 8.7 (JXA1-like). Animal experiments revealed discrepancies in virulence between PRRSV2/CN/SS0/2020 and PRRSV2/CN/L3/2021. The strain with high homology to HP-PRRSV demonstrates higher pathogenicity for pigs than the other isolate with low homology to HP-PRRSV. Taken together, our findings suggest that PRRSVs have undergone genome evolution by recombination among field strains/MLV-like strains of different lineages.
Christopher Thron, Vianney Mbazumutima, Luis V. Tamayo
et al.
Abstract In epidemiology, the effective reproduction number R e $R_{e}$ is used to characterize the growth rate of an epidemic outbreak. If R e > 1 $R_{e} >1$ , the epidemic worsens, and if R e < 1 $R_{e}< 1$ , then it subsides and eventually dies out. In this paper, we investigate properties of R e $R_{e}$ for a modified SEIR model of COVID-19 in the city of Houston, TX USA, in which the population is divided into low-risk and high-risk subpopulations. The response of R e $R_{e}$ to two types of control measures (testing and distancing) applied to the two different subpopulations is characterized. A nonlinear cost model is used for control measures, to include the effects of diminishing returns. Lowest-cost control combinations for reducing instantaneous R e $R_{e}$ to a given value are computed. We propose three types of heuristic strategies for mitigating COVID-19 that are targeted at reducing R e $R_{e}$ , and we exhibit the tradeoffs between strategy implementation costs and number of deaths. We also consider two variants of each type of strategy: basic strategies, which consider only the effects of controls on R e $R_{e}$ , without regard to subpopulation; and high-risk prioritizing strategies, which maximize control of the high-risk subpopulation. Results showed that of the three heuristic strategy types, the most cost-effective involved setting a target value for R e $R_{e}$ and applying sufficient controls to attain that target value. This heuristic led to strategies that begin with strict distancing of the entire population, later followed by increased testing. Strategies that maximize control on high-risk individuals were less cost-effective than basic strategies that emphasize reduction of the rate of spreading of the disease. The model shows that delaying the start of control measures past a certain point greatly worsens strategy outcomes. We conclude that the effective reproduction can be a valuable real-time indicator in determining cost-effective control strategies.
The relevance of the study is that a comparative analysis of the conditions of readiness for neo-industrialization of economic systems (states, regions, industrial complexes, industrial enterprises), taking into account the totality of obstacles and risks, makes it possible to establish competitive advantages and weaknesses of objects, strategic and operational directions, effective tools for achieving goals in a new technological order. The aim of the study is to carry out a comparative analysis of the conditions for the readiness of the industry in Russia and Ukraine for neo-industrialization based on digitalization. The methodological basis of the research is made up of general and general scientific methods of cognition, as well as the concrete historical method, the comparative historical method, the method of the unity of the historical and the logical, the method of comparative analysis, etc.
Considering that Russia and Ukraine had equal starting conditions for the beginning of neo-industrialization after the collapse of the USSR, and in the post-Soviet period there were a number of general tendencies in de-industrialization, then the modern experience of Russia should be considered as a standard for a number of post-Soviet countries. The article presents the main results of a comparative analysis of obstacles (institutional, technological, socio-economic) to neo-industrialization in Russia and Ukraine. It has been substantiated that synergistic and multiplier effects from neo-industrialization can be obtained through complex solutions in the spheres of institutions, technologies and economics. The study also presents a classification of risks (by levels of formation: global, supra-organizational, including sectoral, organizational; by areas: social, environmental, cyber-physical, etc.) of neo-industrialization and assessed them.
It has been established that against the background of the continuing «active» processes of de-industrialization in the Ukrainian industry, the Russian industry has a much higher degree of readiness for neo-industrialization, including due to the digitalization of the manufacturing industry. The process of de-industrialization in Ukraine can be stopped only with economic integration with Russia. Having a sufficiently high scientific and educational potential, states should transform it as actively as possible into fundamental innovations: technological, institutional, managerial, product innovations.
The practical significance of the obtained research results lies in the fact that the developed scientific and methodological approaches allow assessing the level of readiness of economic systems for neo-industrialization and comparative analysis with the standard, diagnosing competitive advantages and weaknesses, which should be further taken into account when justifying and implementing strategic and operational decisions. In subsequent publications, the results will be presented, reflecting the developed applied directions and proposed measures to accelerate the neoindustrialization of the two countries, taking into account the spatial and industrial, technological, institutional, organizational and managerial, financial and economic and quantitative (economic and mathematical modeling of the «digital factor» of production) aspects.
Onaiwu Oduwa David, Usiosefe Ikponmwosa, Okon Samuel
Generating pressure transient response for an interpretation model to describe essential features of a reservoir system accurately is often difficult. It is generally due to the inaccessibility of standard pressure transient analysis tools due to the cost, and even when accessible, they are constrained to its workflow and limitations. This study presents an alternative to standard industry tools to determine transient pressure response for a given rate history. A reservoir model for a single well with constant skin and wellbore storage producing a varying step rate in a semi-infinite acting reservoir with a sealing fault was used as a case study. The well is also assumed to be producing above saturation pressure from a reservoir saturated with slightly compressible fluid hence having constant fluid properties. The method discussed in this study can be applied to well-test interpretation models with an analytical constant terminal rate solution producing at variable step rates from a reservoir having constant rock and fluid properties. The results show conformance with that of standard industry software, and diagnostic plots of the simulated data set can help engineers plan well-test jobs and study the behavior of different reservoir models. Moreover, the program can be modified and used to regress observed pressure response with a selected model. The approach suggested by this study is a perfect alternative where time and cost are constraints.
Extruded polystyrene (XPS) and its excellent thermal insulation properties have been known for over 60 years. Due to its thermal, mechanical, but also deformation properties, XPS has a universal application, not only in the construction industry. This paper presents the results of the first series of experimental measurements of the deformation resistance of the sub-ballast layers with a built-in XPS thermal insulation layer and the sub-ballast layers with a standard structure (crushed aggregate sub-ballast layer). The aim of the first series of experimental measurements was to determine the impact of placing the XPS layer at the subgrade surface level (deformation resistance of subgrade surface E0 = approx. 10MPa or 30MPa) on the deformation resistance of the sub-ballast layers and then to determine the necessary thickness of the sub-ballast layer in relation to the required deformation resistance at the sub-ballast upper surface. Experimental measurements carried out so far show that the application of XPS boards in the sub-ballast layers has almost no or minimal effect on its deformation resistance. Since XPS boards have significantly better thermal technical properties compared to crushed aggregate, considerable savings of this material can be achieved in areas with unfavorable climatic conditions (high values of air frost index).
Mpho. S. Mafa, Samkelo Malgas, Abhishek Bhattacharya
et al.
Sweet sorghum bagasse (SSB) and corncob (CC) have been identified as promising feedstocks for the production of second-generation biofuels and other value-added chemicals. In this study, lime (Ca(OH)<sub>2</sub>) and NaOH pretreatment efficacy for decreasing recalcitrance from SSB and CC was investigated, and subsequently, the pretreated biomass was subjected to the hydrolytic action of an in-house formulated holocellulolytic enzyme cocktail (HEC-H). Compositional analysis revealed that SSB contained 29.34% lignin, 17.75% cellulose and 16.28% hemicellulose, while CC consisted of 22.51% lignin, 23.58% cellulose and 33.34% hemicellulose. Alkaline pretreatment was more effective in pretreating CC biomass compared to the SSB biomass. Both Ca(OH)<sub>2</sub> and NaOH pretreatment removed lignin from the CC biomass, while only NaOH removed lignin from the SSB biomass. Biomass compositional analysis revealed that these agricultural feedstocks differed in their chemical composition because the CC biomass contained mainly hemicellulose (33–35%), while SSB biomass consisted mainly of cellulose (17–24%). The alkaline pretreated SSB and CC samples were subjected to the hydrolytic action of the holocellulolytic enzyme cocktail, formulated with termite derived multifunctional enzymes (referred to as MFE-5E, MFE-5H and MFE-45) and exoglucanase (Exg-D). The HEC-H hydrolysed NaOH pretreated SSB and CC more effectively than Ca(OH)<sub>2</sub> pretreated feedstocks, revealing that NaOH was a more effective pretreatment. In conclusion, the HEC-H cocktail efficiently hydrolysed alkaline pretreated agricultural feedstocks, particularly those which are hemicellulose- and amorphous cellulose-rich, such as CC, making it attractive for use in the bioconversion process in the biorefinery industry.
AbstractSildenafil is known to reduce cardiac hypertrophy through cGMP-dependent protein kinase (cGK) activation. Studies have demonstrated that cGK has a central switching role in modulating vascular smooth muscle cell (VSMC) phenotype in response to vascular injury. Here, we aimed to examine the effects of cGK activation by sildenafil on neointimal formation and platelet aggregation. After vascular injury, neointimal hyperplasia in rat carotid arteries was significantly reduced in the sildenafil-treated group. This effect of sildenafil was accompanied by the reduction of viability and migration of VSMCs. Further experiments showed that the increased cGK activity by sildenafil inhibited platelet-derived growth factor-induced phenotype change of VSMCs from a contractile form to a synthetic one. Conversely, the use of cGK inhibitor or gene transfer of dominant-negative cGK reversed the effects of sildenafil, increasing viability of VSMCs and neointimal formation. Interestingly, sildenafil significantly inhibited platelet aggregation induced by ADP or thrombin. This effect was reversed by cGK inhibitor, suggesting that sildenafil inhibits platelet aggregation via cGK pathway. This study demonstrated that sildenafil inhibited neointimal formation and platelet aggregation via cGK pathway. These results suggest that sildenafil could be a promising candidate for drug-eluting stents for the prevention of both restenosis and stent thrombosis.
AbstractA lack of information regarding whether genetic polymorphisms of SLCO1B1 and ABCG2 affect the pharmacokinetics (PKs)/pharmacodynamics (PDs) of rosuvastatin in elderly subjects prevents optimal individualized pharmacotherapy of rosuvastatin in clinical settings. This study aimed to investigate the effect of age and genetic polymorphisms and possible differences in genetic effects on the PKs/PDs of rosuvastatin between elderly and young subjects. Two separate clinical studies designed as open-label, one-sequence studies with multiple-dose administration for elderly (n = 20) and young (n = 32) subjects were conducted. All subjects received 20 mg of rosuvastatin once daily for 21 days. The exposure to rosuvastatin, characterized by the area under the time curve (AUC), increased by 23% in the elderly subjects compared with that of young subjects, which was not significant. When compared to the subjects with breast cancer resistance protein (BCRP) normal function, the exposure to rosuvastatin increased by 44% in young subjects (p = 0.0021) with BCRP intermediate function (IF) and by 35% and 59% (p > 0.05 for both) in elderly subjects with BCRP IF and low function, respectively. SLCO1B1 521T > C was also partially associated with a higher AUC of rosuvastatin in young subjects and a less pronounced increasing trend in elderly subjects (p > 0.05 for both). The lipid-lowering effect of rosuvastatin was less pronounced in the elderly subjects than in the young subjects, and genetic polymorphisms of neither SLCO1B1 nor ABCG2 significantly affected the PDs of rosuvastatin. The ABCG2 421C > A polymorphism was associated with the PKs of rosuvastatin and was identified as a more important determinant than the SLCO1B1 521T > C polymorphism in both elderly and young subjects.
Penelitian ini bertujuan untuk mengetahui fungsi lain dari makanan dan tradisi makan dari gastronomi menjadi gastrodiplomasi dalam masyarakat, dengan memahami misi dan visi dari dibuatnya tradisi Megibung sebagai sarana pengendalian sosial di masyarakat baik di masa lampau maupun sekarang dan yang akan datang, serta peran dari Pemda setempat dalam membangun citra kuliner setempat menjadi ekonomi kreatif. Metode penelitian yang digunakan memecahkan atau menjawab seluruh masalah yang ada dalam penelitian ini adalah metode kualitatif.
Hasil penelitian menunjukkan bahwa tradisi Megibung sejak awal sejarahnya sudah diciptakan sebagai sarana diplomasi bagi masyarakat petani di sawah, kemudian berkembang menjadi sarana diplomasi untuk konsolidasi pasukan/laskar perang oleh raja Karangasem dalam merebut Sasak. Pada pasca perang dimanfaatkan untuk sarana rekonsiliasi antar etnis (Sasak dan Bali) dan umat (Islam dan Hindu) dalam mendukung eksistensi kekuatan kerajaan Karangasem. Kemudian di masa damai ini menjadi sarana budaya membangun solidaritas persatuan dan kesatuan masyarakat dari lapisan bawah sampai atas, serta sarana diplomasi antar bangsa dengan konsep glokal (globalisasi lokalitas) tanpa sekat kelas sosial dan materi.
Mengingat tingginya nilai budaya Megibung, yang di masa global ini mulai mendapat tantangan karena adanya catering (prasmanan) yang lebih simpel dan praktis. Untuk itu dibutuhkan program penyelamatan agar tidak punah ditelan zaman. Warisan tradisi ini harus terus dijaga dan direvitalisasi agar dapat diwariskan kepada generasi mendatang dengan menjadikan tradisi Megibung sebagai sarana pembangunan ekonomi kreatif di Karangasem. Melalui tradisi Megibung generasi muda dapat belajar magang dalam mengolah berbagai jenis masakan tradisional Bali yang dapat dijadikan bekal untuk modal keahlian dalam bisnis ekonomi kreatif di bidang pariwisata, yang secara bersamaan otomatis juga telah ikut melestarikan keberlanjutan dari tradisi budaya Megibung itu sendiri. Oleh karena itu, Pemda Karangasem harus bisa mendorong pengembangan pariwisata budaya berkelanjutan menuju ekonomi kreatif yang mengutamakan kepuasan wisata kuliner atau gastronomi khususnya.
Hospitality industry. Hotels, clubs, restaurants, etc. Food service
Hsien-Chin Chiu, Chia-Hao Liu, Yi-Sheng Chang
et al.
The surface morphology optimization of ohmic contacts and the Mg out-diffusion suppression of normally off p-GaN gate high-electron-mobility transistors (HEMTs) continue to be challenges in the power electronics industry in terms of the high-frequency switching efficiency. In this study, better current density and reliable dynamic behaviors of p-GaN gate HEMTs were obtained simultaneously by adopting low-temperature microwave annealing (MWA) for the first time. Moreover, HEMTs fabricated using MWA have a higher ION/IOF ratio and lower gate leakage current than the HEMTs fabricated using rapid thermal annealing. Due to the local heating effect, a direct path for electron flow can be formed between the two-dimensional electron gas and the ohmic metals with low bulges surface. Moreover, the Mg out-diffusion of p-GaN gate layer was also suppressed to maintain good current density and low interface traps.
Agung Wahyono, Elly Kurniawati, Kasutjianingati
et al.
Yellow pumpkin (Cucurbita moscata) is a popular plant in Indonesia, but its utilization is limited. It has been reported that the antioxidant activity of the yellow pumpkin increased by increasing the drying tempe-rature and immersing the pumpkin in bisulfite solution during processing. The aim of this study was to opti-mize the processing conditions for the manufacturing of pumpkin flour using Response Surface Methodo-logy (RSM) to enhance its antioxidant activities. The optimization process was done using a Box-Behnken construction. The factorial treatments consisted of immersion in metabisulfite solution, drying temperature, and drying time. The results showed that the scavenging activity as measured by DPPH and ABTS corres-ponded well to the independent variables based on the multiple regression analysis particularly the multi-variate quadratic regression (MQR). Based on the MQR, the determination coefficients (R2) of DPPH and ABTS were 0.97 and 0.96, respectively. Based on that model, the optimum conditions of pumpkin flour manufacturing were immersion in metabisulfite solution for 23.05 min, drying temperature of 85°C, and drying time of 11.40 h. This optimum condition was predicted to yield pumpkin flour having DPPH and ABTS scavenging activities of 90.12% and 94.38%, respectively. Based on the validation data, the optimum condition resulted in flour with antioxidant activities of 80.23 (DPPH) and 86.67% (ABTS). The quadratic models developed were powerful in predicting the actual values of the antioxidant activity by DPPH and ABTS. The accuracy of the models in predicting the antioxidant activity by DPPH and ABTS were 89.02 and 91.83%, respectively.
This paper focuses on iron-based soft magnetic composites which were synthesized by utilizing the sol-gel method prepared Ni-Zn ferrite particles as insulating compound to coat iron powder, and the influence of NiZnFe<sub>2</sub>O<sub>4</sub> content and molding pressure on the magnetic properties was studied. The morphology, magnetic properties and density of Ni-Zn ferrite insulated compacts were investigated. Scanning electron microscope,line-scan EDX analysis and distribution maps show that the iron particle surface is covered with a thin layer of uniform Ni-Zn ferrites. The existing of the insulating layer can effectively improve the electrical resistivity of soft magnetic composites. Magnetic measurements show that the real part of permeability decreases with the increase of the Ni-Zn ferrite content, and the sample with 3%(mass fraction, the same below) Ni-Zn ferrite has an acceptable real part and minimum imaginary part of permeability in comparison with other samples. Results show that the addition of NiZnFe<sub>2</sub>O<sub>4</sub> can dramatically decrease the internal magnetic loss, the magnetic loss of coated samples decreases by 83.8% as compared with that of uncoated samples at 100kHz. The density of the Fe-3%NiZnFe<sub>2</sub>O<sub>4</sub> compacts reaches 7.14g/cm<sup>3</sup> and the saturation magnetization is 1.47T when the molding pressure is 1000MPa.
Materials of engineering and construction. Mechanics of materials