scholarly journals Effect of nanosecond electropulse effects on the properties of the alloy Cu-1.75% Cr

2019 ◽  
Vol 58 (5) ◽  
pp. 133-140
Author(s):  
Igor E. Ignatiev ◽  
◽  
Pavel V. Kotenkov ◽  
Elena V. Ignatieva ◽  
Eduard Yu. Goyda ◽  
...  

The hardness, electrical resistance, deformation resistance of the Cu-1.75%Cr alloy obtained by irradiating its melt at a temperature of one thousand three hundred and fifty degrees Celsius by nanosecond unipolar electrical pulses of one thousand Hertz, a single signal duration of one nanosecond and ten kilowatts were experimentally determined. The dependences of the determined properties of the metal on the duration of the electric pulse irradiation are established. A comparison was made between irradiated and unirradiated, but obtained under the same thermal and temporal conditions, alloy samples. An improvement was observed in both mechanical (increase in hardness up to eight percent) and electrical (decrease in electrical resistance to fourteen and a half percent) characteristics due to electric pulse effect on the melt. It was found that the best time for electropulse treatment is from five to ten minutes. It is shown that the effect of irradiation of the Cu-1.75%Cr melt on the electrical resistance of the resulting alloy and its hardness differs from the results of irradiation of the Cu-1%Cr melt, but retains the same tendencies in changing properties. A significant difference was found in the hardness values of unirradiated samples of Cu-1.75%Cr and Cu-1%Cr alloys. A model of the connection of electrical resistance and hardness of Cu-Cr alloys with the redistribution of chromium in their volume is proposed. The results of melt processing by nanosecond unipolar electric pulses are presented in the form of microstructure snapshots, tables, and mathematical formulas. On the basis of the obtained results, it was concluded that the proposed model is useful for assessing the quality of Cu-Cr system alloys from the standpoint of increasing their hardness and decreasing electrical resistance, including after electropulse treatment of the corresponding melts.

2013 ◽  
Vol 25 (1) ◽  
pp. 220
Author(s):  
R. Li ◽  
Y. Liu ◽  
H. Pedersen ◽  
P. Kragh ◽  
P. Hyttel ◽  
...  

During in-vitro handling, oocytes and embryos are always exposed to light. This has been shown to affect embryonic development and quality in different species, i.e. hamster and mouse (Takenaka et al. 2007 PNAS, 104, 14 289–14 293) and human (Tatsuo et al. 2010 J. Assist. Reprod. Genet. 27, 93–96). However, similar experiments have not been made on porcine embryos, so our aim was to test effects of different types of light on the development and quality of porcine parthenote embryos. Cumulus–oocyte complexes from slaughterhouse-derived sow ovaries were aspirated and matured (38.5°C, 5% CO2, maximum humidity, 42 h). Parthenogenetic activation was made (Day 0) first by an electric pulse (1.26 kV cm–1, 80 µs) and then by incubation with 5 µg mL–1 cytochalasin B and 10 µg mL–1 cycloheximide in porcine zygote medium-3 (PZM-3) for 4 h. During these processes, the oocytes would be exposed to ~30 min of light. After activation, the oocytes were either directly cultured in incubator (0 h), or experimentally exposed to two types of light (DAY: near window, no direct sunlight; LAB: app. 40 cm from warm white lamps (12 V, 40 W) in PZM-3 while placed on a heating plate (38.5°C) with the culture dish covered by a crystal plastic foil filled with the appropriate gas (5% O2, 5% CO2) for different periods (1 h, 4 h, 24 h), and then cultured in PZM-3 in incubator. On Day 6, total and good blastocysts were counted. Good blastocysts were defined as blastocysts having expanded to 1.5 times the oocytes’ size, having cells of uniform color and distribution, and having formed a regular blastocyst cavity. The total number of cells and the apoptotic cells were detected on Day 6 blastocysts with TUNEL assay to evaluate embryonic quality. All statistics analysis were performed by ANOVA test (R). The results are summarized in Table 1. The developmental rates were decreased with both types of light: the decrease appeared earlier for good blastocyst rates, only after 1 h exposure; however, a clear adverse effect was also found on total blastocyst rates after 24 h exposure. The total cell number decreased after 4 h light exposure for both types of light. The rate of apoptotic cells tended to increase with both types of light (from approximately 7 to 9.5%) when embryos were exposed during 24 h, but no significant difference was found between groups. We conclude that the blastocyst morphology would be altered already after 1 h extra exposure to both light types, and their quality would further decrease after 4 h exposure. However, under normal working conditions, this should not represent a real problem. Table 1.Effect of light exposure on development of porcine parthenote embryos


2019 ◽  
Vol 57 (1) ◽  
pp. 127-135
Author(s):  
Igor E. Ignatiev ◽  
◽  
Pavel V. Kotenkov ◽  
Eduard Yu. Goyda ◽  
Elena V. Ignatieva ◽  
...  

The effect of treatment of copper melt with chromium additives in the amount of 1% by weight is considered nanosecond unipolar electric pulses with a frequency of 1000 Hz, a single signal duration of one nanosecond and a power of 10 kW on the electrical resistivity and hardness of the resulting alloy. A study was made of the macro and microstructure of alloy samples created using electropulse effects and comparison samples obtained under the same thermal conditions, but without it. The samples were aged for 2 hours at 4500C. It has been found that electropulse treatment of the melt leads to an increase in hardness and decrease in the electrical resistance of the alloy as well as during aging, and the influence of this effect remains noticeable even after the aging process. Hardness and electrical resistance in all alloy samples are described mathematically as a function of chromium content in the copper lattice and in secondary precipitates. The role of nanosecond unipolar electroimpulsive effects on the Cu-1% Cr melt in improving the above characteristics of the resulting alloy compared with the thermo-time treatment without the electropulse effect is revealed. An explanation of the mechanism of the electropulse effect on the melt, leading to the separation of chromium atoms in the liquid state and the subsequent decrease in its solubility in the copper lattice, is proposed. The results of the study are presented in the form of drawings of macro- and microstructure of samples of the alloy Cu-1% Cr, tables, graphs and mathematical formulas. It was concluded that it is advisable to use a nanosecond unipolar electropulse effect with a frequency of 1000 Hz, a single signal duration of one nanosecond and a power of 10 kW per Cu-1% Cr melt to produce the corresponding alloy with improved hardness and electrical resistance.


2020 ◽  
Vol 50 (1) ◽  
pp. 106-114
Author(s):  
Ivan Shorstkii

Introduction. One of the most important tasks of the modern oil and cake industry is to develop advanced technologies that could increase the yield of high quality oil and related target components from oilseeds. Study objects and methods. The present research featured sunflower oilseeds. The main method of electrical treatment processing was high-voltage electrical pulses of microsecond duration: electric field strength = 13.3 kV/cm, frequency = 30 Hz. To assess the effects of electric pulses, we used disintegration index, i.e. a method of determining the number of destroyed cells according to the electrical conductivity of the material. To assess the effect of the treatment, the sunflower meal was pressed in a hydraulic press. The procedure was followed by extraction using hydrocarbon solvent. As an additional assessment, we analyzed the biomass impedance before and after treatment with high-voltage discharges with the determination of the disintegration index. To assess the quality of the resulting oil, we determined the acid and peroxide values. IR spectroscopy provided a more thorough assessment of the quality of the oil. Results and discussion. After the sunflower meal was treated with high-voltage pulses, the yield of pressed oil increased by 1.9%. The residual oil content in the meal fell down to 0.61% compared with 1.19% in the control samples. Oil quality indicators showed that treatment with high-voltage pulses did not significantly affect the acid value. The sudden change in the peroxide number was probably caused by the prolonged heating during the experiment. Conclusion. The obtained experimental data made it possible to forecast the prospects of using the high-voltage electric pulse for oilseed processing and assess the effectiveness of the technology together with its prospective industrial use. The alternative technology can replace the stage of crushing and pre-heating.


2014 ◽  
Vol 6 (1) ◽  
pp. 1032-1035 ◽  
Author(s):  
Ramzi Suleiman

The research on quasi-luminal neutrinos has sparked several experimental studies for testing the "speed of light limit" hypothesis. Until today, the overall evidence favors the "null" hypothesis, stating that there is no significant difference between the observed velocities of light and neutrinos. Despite numerous theoretical models proposed to explain the neutrinos behavior, no attempt has been undertaken to predict the experimentally produced results. This paper presents a simple novel extension of Newton's mechanics to the domain of relativistic velocities. For a typical neutrino-velocity experiment, the proposed model is utilized to derive a general expression for . Comparison of the model's prediction with results of six neutrino-velocity experiments, conducted by five collaborations, reveals that the model predicts all the reported results with striking accuracy. Because in the proposed model, the direction of the neutrino flight matters, the model's impressive success in accounting for all the tested data, indicates a complete collapse of the Lorentz symmetry principle in situation involving quasi-luminal particles, moving in two opposite directions. This conclusion is support by previous findings, showing that an identical Sagnac effect to the one documented for radial motion, occurs also in linear motion.


2019 ◽  
Vol 118 (7) ◽  
pp. 1-19
Author(s):  
Geethanjali N ◽  
Parveen Roja M ◽  
Lavanya D

Quality of work life is the major factor to be considered in working environment of any organization. The performance of employees and the organization lies on the ability of the employees based on working environment. The QWL leads to better working environment which improves the performance of organization. The present study has made an attempt to find the level of factors causing QWL and the impact of outcome of QWL in banks. Since the profile of the banks may be associated with the level of outcomes of QWL, the present study has made an attempt to examine it with the help of one way analysis of variance and t-test. The included outcomes of QWL are job satisfaction, job stress, organizational climate, organizational commitment, employees retention behaviour, service quality employees and service productivity of employees. The highly associated determinants of QWL and the significant difference among the PUSBs and PRSBs have been noticed. The significantly associating important profiles of the banks regarding the existence of outcome of QWL are identified.


Author(s):  
A. V. Ponomarev

Introduction: Large-scale human-computer systems involving people of various skills and motivation into the information processing process are currently used in a wide spectrum of applications. An acute problem in such systems is assessing the expected quality of each contributor; for example, in order to penalize incompetent or inaccurate ones and to promote diligent ones.Purpose: To develop a method of assessing the expected contributor’s quality in community tagging systems. This method should only use generally unreliable and incomplete information provided by contributors (with ground truth tags unknown).Results:A mathematical model is proposed for community image tagging (including the model of a contributor), along with a method of assessing the expected contributor’s quality. The method is based on comparing tag sets provided by different contributors for the same images, being a modification of pairwise comparison method with preference relation replaced by a special domination characteristic. Expected contributors’ quality is evaluated as a positive eigenvector of a pairwise domination characteristic matrix. Community tagging simulation has confirmed that the proposed method allows you to adequately estimate the expected quality of community tagging system contributors (provided that the contributors' behavior fits the proposed model).Practical relevance: The obtained results can be used in the development of systems based on coordinated efforts of community (primarily, community tagging systems). 


2018 ◽  
Vol 8 (6) ◽  
pp. 76-81
Author(s):  
Chu Cao Minh ◽  
Thang Vo Van ◽  
Dat Nguyen Tan ◽  
Hung Vo Thanh

Background: The criteria set of assessing hospital quality in Vietnam in 2016 was revied from the criteria set in 2013 by the Ministry of Health in order to help hospitals to self-assess towards improvinge quality of hospitals in the international integration context. The study aimed to assess the quality of public hospitals in Can Tho City according to the revised criteria set of the Ministry of Health in 2016 and compare the quality among three hospital ranks (including grade I, grade II, and grade III) via to 5 groups of quality criteria. Methods: A cross-sectional study, using secondary data analysis was applied to assess the service quality of 7 general public hospitals in Can Tho City. Results: The average total score of 7 hospitals is 245 and the average for the criteria of 7 hospitals is 2.99, which is just satisfactory. In the criterion of quality, criterion D and E had the lowest scores compared to the other three groups. There was no statistically significant difference (p = 0.076) among the mean scores for the three hospital categories. Conclusion: The quality of public hospitals in Can Tho city in 2016 only reached moderately good level (2.99). Interventions should be developed to improve the quality of hospitals, with particular emphasis on improving the quality of criteria groups D and E. Key words: Quality, hospital, medicine, health, public, Can Tho


2008 ◽  
Vol 47 (01) ◽  
pp. 37-42 ◽  
Author(s):  
T. Pfluger ◽  
V. Schneider ◽  
M. Hacker ◽  
N. Bröckel ◽  
D. Morhard ◽  
...  

SummaryAim: Assessment of the clinical benefit of i.v. contrast enhanced diagnostic CT (CE-CT) compared to low dose CT with 20 mAs (LD-CT) without contrast medium in combined [18F]-FDG PET/CT examinations in restaging of patients with lymphoma. Patients, methods: 45 patients with non-Hodgkin lymphoma (n = 35) and Hodgkin's disease (n = 10) were included into this study. PET, LD-CT and CECT were analyzed separately as well as side-by-side. Lymphoma involvement was evaluated separately for seven regions. Indeterminate diagnoses were accepted whenever there was a discrepancy between PET and CT findings. Results for combined reading were calculated by rating indeterminate diagnoses according the suggestions of either CT or PET. Each patient had a clinical follow-up evaluation for >6 months. Results: Region-based evaluation suggested a sensitivity/specificity of 66/93% for LD-CT, 87%/91% for CE-CT, 95%/96% for PET, 94%/99% for PET/LD-CT and 96%/99% for PET/CE-CT. The data for PET/CT were obtained by rating indeterminate results according to the suggestions of PET, which turned out to be superior to CT. Lymphoma staging was changed in two patients using PET/ CE-CT as compared to PET/LD-CT. Conclusion: Overall, there was no significant difference between PET/LD-CT and PET/CE-CT. However, PET/CE-CT yielded a more precise lesion delineation than PET/LD-CT. This was due to the improved image quality of CE-CT and might lead to a more accurate investigation of lymphoma.


2017 ◽  
Vol 3 (1) ◽  
Author(s):  
Tri Nurhudi Sasono

Abstract : Indicator of the health welfare through Sustanable Development Goals (SDGs) is to reduce the incidence of HIV-AIDS, decrease the rate of the epidemic and maintain the quality of life of people living with HIV-AIDS (PLWHA). Trend cases of HIV-AIDS is the most recent spread among people, especially housewives. In Malang until 2015 found 278 Housewife of 409 cases of AIDS. The prevalence of HIV-AIDS in Malang Regency is ranked second after Surabaya city in East Java. For the importance of public participation and citizen care AIDS Cahaya Care Turen take responsibility for the condition. Determination Rule Goverment number 2 2015 year on the Participation of the community response to HIV-AIDS in Malang as a legal rule. Concerned Citizens activities AIDS (WPA). WPA Cahaya Care Turen is increases HIV risk and quality of life PLWHA. The purpose of this study was to determine the role of Citizens AIDS Cahaya Care Quality of Care Turen against people living with HIV in Puskesmas Turen Malang. The study design using a quasi-experimental, with purposive sampling using a sampling technique. Total number of research subjects 23. Based on test results obtained with the Wilcoxon p value <0.005, which means that there is a significant difference before and after PLWHA joining participated in the WPA Cahaya Care Turen. The conclusion of this study is WPA activities involving people living with HIV and at risk groups can optimize compliance with antiretroviral drugs that have an impact on improving the quality of life of PLHIV. Suggestions in this research is done WPA Program activities are structured and ongoing cross-sector in order to improve the quality of life and empower PLWHA.Keywords : WPA Cahaya Care Turen, Quality of life, PLWHA Abstrak : Salah satu indikator kesejahteraan kesehatan melalui Sustanable Development Goals (SDGs) adalah menekan angka kejadian HIV-AIDS, menurunkan laju epidemik dan mempertahankan kualitas hidup Orang dengan HIV-AIDS (ODHA). Trend kasus HIV-AIDS terkini terbanyak adalah menjangkit dikalangan masyarakat khususnya pada ibu rumah tangga. Kabupaten Malang sampai dengan tahun 2015 ditemukan 278 Ibu Rumah Tangga dari 409 kasus AIDS. Prevalensi HIV-AIDS di Kabupaten Malang ini merupakan peringkat kedua di Jawa Timur setelah Kota Surabaya. Untuk itu pentingnya peran serta masyarakat dan warga peduli AIDS Cahaya Care Turen ikut bertanggung jawab terhadap kondisi tersebut. Penetapan Peraturan Bupati Malang no.2 th.2015 tentang Peran serta masyarakat penanggulangan HIV-AIDS di Kabupaten Malang diharapkan dapat mengurangi risiko penularan HIV dan meningkatkan kualitas hidup ODHA. Tujuan dari penelitian ini adalah untuk mengetahui Peran Warga Peduli AIDS Cahaya Care Turen terhadap Kualitas ODHA Di Wilayah Kerja Puskesmas Turen Kabupaten Malang. Desain penelitian menggunakan quasi eksperimen, dengan teknik sampling menggunakan purposive sampling. Jumlah subyek penelitian sejumlah 23. Berdasarkan hasil uji dengan Wilcoxon didapatkan nilai p value < 0.005 yang berarti bahwa terdapat perbedaan bermakna sebelum dan sesudah ODHA bergabung mengikuti kegiatan WPA Cahaya Care Turen. Kesimpulan dalam penelitian ini adalah kegiatan WPA dengan melibatkan ODHA dan kelompok beresiko dapat mengoptimalkan kepatuhan obat ART sehingga berdampak terhadap peningkatan kualitas hidup ODHA. Saran dalam penelitian ini adalah dilakukannya Program kegiatan WPA yang terstruktur dan berkesinambungan lintas sektor guna meningkatkan kualitas hidup dan memberdayakan ODHA.     Kata kunci : WPA Cahaya Care Turen, kualitas hidup, ODHA


This article presents the results of studying the impact of housing and feeding conditions on broiler chickens of Hubbard RedBro cross, as well as the quality of products obtained when using floor and cage content, in a farm. It established that when receiving a mixed feed of own production using feed raw materials grown on a farm without the use of pesticides, a statistically significant decrease in potentially dangerous substances for animal health is recorded. Compared with factory feed, it has reduced the content of pesticides by 14 times, and mercury and arsenic by 24 times, cadmium by five times, and lead by ten times. The results of the study of economic indicators of growing Hubbard RedBro cross broiler chickens, as well as the chemical composition and quality of carcasses, indicated that there was no significant difference between the floor and cell conditions of keeping. Still, the use of a diet based on eco-feeds contributed to a statistically significant decrease in the concentration of toxic metals in the muscles of the poultry of the experimental groups. As a result, it found that the use of the studied compound feed in the diets of broiler chickens increased the indicators of Biosafety and ensured the production of environmentally safe ("organic") poultry meat products.


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