• Title/Summary/Keyword: Sphericity

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Peeling Operations of Root Vegetables: Potato, Sweet Potato and Carrot (근채류(감자, 고구마, 당근)의 탈피조작)

  • Lee, Cherl-Ho;Lee, Soon-Woo
    • Korean Journal of Food Science and Technology
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    • v.16 no.3
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    • pp.329-335
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    • 1984
  • The effect of peeling methods, spherecity and weight of potatoes and carrots on the peeling efficiency were investigated. The changes in the surface texture by peeling were estimated by Rheometer and were related to the changes in the microstructure. The optimum mechanical peeling conditions using abrasion type rotary peeler were 90 sec. at 300 rpm for potatoes, 70 sec. at 300 rpm for sweet potatoes and 60 sec. at 300 rpm for carrots. The peeling loss was influenced by the sphericity and weight of the sample. The optimum conditions for alkali peeling were 90 sec. immersion in boiling 10% NaOH solution for potatoes, 300 sec. in boiling 10% NaOH solution for sweet potatoes and 60 sec. in boiling 6% NaOH solution for carrots. Severe damage of surface structure was noticed by alkali peeling, demonstrated by denaturation of starch granules in the cell. The structural damage observed by microscope was related to the reduction of cutting force after peeling.

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Influences of heating processes on properties and microstructure of porous CeO2 beads as a surrogate for nuclear fuels fabricated by a microfluidic sol-gel process

  • Song, Tong;Guo, Lin;Chen, Ming;Chang, Zhen-Qi
    • Nuclear Engineering and Technology
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    • v.51 no.1
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    • pp.257-262
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    • 2019
  • The control of microstructure is critical for the porous fuel particles used for infiltrating actinide nuclides. This study concerns the effect of heating processes on properties and microstructure of the fuel particles. The uniform gel precursor beads were synthesized by a microfluidic sol-gel process and then the porous $CeO_2$ microspheres, as a surrogate for the ceramic nuclear fuel particles, were obtained by heating treatment of the gel precursors. The fabricated $CeO_2$ microspheres have a narrow size distribution and good sphericity due to the feature of microfluidics. The effects of heating processes parameters, such as heating mode and peak temperatures on the properties of microspheres were studied in detail. An optimized heating mode and the peak temperature of $650^{\circ}C$ were selected to produce porous $CeO_2$ microspheres. The optimized heating mode can avoid the appearance of broken or crack microspheres in the heating process, and as-prepared porous microspheres were of suitable pore size distribution and pore volume for loading minor actinide (MA) solution by an infiltration method that is used for fabrication of MA-bearing nuclear fuel beads. After the infiltration process, $1000^{\circ}C$ was selected as the final temperature to improve the compressive strength of microspheres.

Study on the Fabrication of Porous Uranium Oxide Granule Using a Rotary Voloxidizer (회전형 휘발성 산화장치 이용 다공성 우라늄산화물 그래뉼 제조 연구)

  • Lee, Jae-Won;Yun, Yeo-Wan;Shin, Jin-Myeong;Lee, Jung-Won;Park, Guen-IL;Park, Jang-Jin
    • Applied Chemistry for Engineering
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    • v.22 no.6
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    • pp.642-647
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    • 2011
  • The fabrication characteristics of porous uranium oxide granules from $U_3O_8$ powder was investigated in terms of initial particle bed motions such as slumping and rolling, thermal treatment conditions, and rotational velocities in slumping motion using a rotary voloxidizer. With respect to the initial particle bed motion the recovery rate of granule of above 1 mm in slumping motion was higher than that in the rolling motion. Rolling motion was changed into slumping motion with high slumping frequency by formation of granules from fine particles. Recovery rate of granule significantly increased with the increas in thermal treatment temperature and time of upto 10 h. As the rotational velocity of voloxidizer in the case of the initial particle bed showing slumping motion increased, the recovery rate of granule increased from 81.5 to 88.7%. However, the rotational velocity of 2 rpm provided an effective density, crushing strength and sphericity of granules.

Preparation by the double extraction process with preliminary neutron irradiation of yttria or calcia stabilised cubic zirconium dioxide microspheres

  • Brykala, Marcin;Walczak, Rafal;Wawszczak, Danuta;Kilim, Stanislaw;Rogowski, Marcin;Strugalska-Gola, Elzbieta;Olczak, Tadeusz;Smolinski, Tomasz;Szuta, Marcin
    • Nuclear Engineering and Technology
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    • v.53 no.1
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    • pp.188-198
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    • 2021
  • A modern approach to nuclear energy involves reprocessing like transmutations of spent nuclear fuel products to reduce their radiotoxicity and time needed for their storage. For this purpose, they are immobilized in inert matrices made of zirconia and can be "burned" in fast neutron reactor or Accelerator Driven System. These matrices in spherical form can be obtained by sol-gel process. The paper presents a method of microspheres fabrication based on the combined Complex Sol-Gel Process and double extraction process consisting in the preparation of zirconium-ascorbate sol and simultaneous extraction of water and nitrates. The procedure allows obtaining gel microspheres with a diameter of 50 ㎛, which after heat treatment are processed into the final product. The synthesis of zirconia microspheres with Yttrium by internal gelation process is well known for over a decade now. However, the explanation and characterization of synthesis of such material by extraction of water process is rarely found. Parameters such as: pH, viscosity, shape, sphericity and crystal structure have been determined for synthesized products and semi-products. In addition, preliminary research consisting in irradiation of the obtained materials in fast and thermal neutron flux was carried out. The obtained results are presented and described in this work.

Optimization of VIGA Process Parameters for Power Characteristics of Fe-Si-Al-P Soft Magnetic Alloy using Machine Learning

  • Sung-Min, Kim;Eun-Ji, Cha;Do-Hun, Kwon;Sung-Uk, Hong;Yeon-Joo, Lee;Seok-Jae, Lee;Kee-Ahn, Lee;Hwi-Jun, Kim
    • Journal of Powder Materials
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    • v.29 no.6
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    • pp.459-467
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    • 2022
  • Soft magnetic powder materials are used throughout industries such as motors and power converters. When manufacturing Fe-based soft magnetic composites, the size and shape of the soft magnetic powder and the microstructure in the powder are closely related to the magnetic properties. In this study, Fe-Si-Al-P alloy powders were manufactured using various manufacturing process parameter sets, and the process parameters of the vacuum induction melt gas atomization process were set as melt temperature, atomization gas pressure, and gas flow rate. Process variable data that records are converted into 6 types of data for each powder recovery section. Process variable data that recorded minute changes were converted into 6 types of data and used as input variables. As output variables, a total of 6 types were designated by measuring the particle size, flowability, apparent density, and sphericity of the manufactured powders according to the process variable conditions. The sensitivity of the input and output variables was analyzed through the Pearson correlation coefficient, and a total of 6 powder characteristics were analyzed by artificial neural network model. The prediction results were compared with the results through linear regression analysis and response surface methodology, respectively.

Li4SiO4 slurry conditions and sintering temperature for fabricating Li4SiO4 pebbles as tritium breeders for nuclear-fusion reactors

  • Young Ah Park;Ji Won Yoo;Yi-Hyun Park;Young Soo Yoon
    • Nuclear Engineering and Technology
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    • v.55 no.8
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    • pp.2966-2976
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    • 2023
  • A tritium breeder is a lithium-based material capable of producing tritium. Many researchers designing nuclear-fusion energy are studying tritium production using pebbles, which are solid-type breeders. The sphericity and size of the pebbles are critical in obtaining pebbles with good tritium-breeding efficiency. Furthermore, tritium-release efficiency can be increased by using pebbles with appropriate porosities. Promising raw materials for tritium-breeding materials include Li4SiO4 and Li2TiO3. Li4SiO4 has a higher lithium density than Li2TiO3 and exhibits excellent tritium-breeding efficiency. However, it has the disadvantage of being easily decomposed during the Li4SiO4-green-pebble sintering process because of its low structural stability at high temperatures and high lithium density. In this study, we attempted to determine the optimal conditions for manufacturing Li4SiO4 pebbles using the droplet-freeze-drying method. The optimal Li4SiO4 slurry conditions and sintering temperatures were determined. The optimal Li4SiO4 slurry-fabrication conditions were 3 wt% polyvinyl alcohol and 75 wt% Li4SiO4 based on the deionized-water weight content. The sintering temperature at which Li4SiO4 did not decompose and exhibited the optimum porosity of 10.8% was 900 ℃.

A comparative study of the physical and cooking characteristics of common types of rice collected from the market by quantitative statistical analysis

  • Evan Butrus Ilia;Mahmood Fadhil Saleem;Hamed Hassanzadeh
    • Food Science and Preservation
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    • v.30 no.4
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    • pp.602-616
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    • 2023
  • Fifteen types of rice collected from Kurdistan region-Iraq were investigated by principal component analysis (PCA) in terms of physical properties and cooking characteristics. The dimensions of evaluated grains correspond to 5.05-8.75 mm for length, 1.54-2.47 mm for width, and 1.37-1.95 for thickness. The equivalent diameter was in the range of 5.23-10.03 mm, and the area took 13.30-28.25 mm2. The sphericity analysis values varied from 0.32 to 0.56, the aspect ratio from 0.17 to 0.39, and the volume of the grain was measured in the range from 4.48 to 17.74 mm3, hectoliter weight values were 730-820 kg/m3, and true density from 0.6 to 0.96 g/cm3. The broken grain ratio was 1.5-18.3%, thousand kernel weight corresponded to 15.88 to 22.42 g. The water uptake ratios for 30 min of soaking were increased at 60℃ compared to 30 and 45℃. The PCA was used to study the correlation of the most effective factors. Results of PCA showed that the first (PC1) and second (PC2) components retained 63.4% and 34.8% of the total variance, which PC1 was mostly related to hectoliter, broken ratio, and moisture content characteristics while PC2 was mostly concerned with hardness and true density. For cooking properties, the PC1 and PC2 retained 88.5% and 9.3% of the total variance, respectively. PC1 was mostly related to viscosity, spring value, and hardness after cooking, while PC2 was mostly concerned with spring value, hardness before cooking, and hardness after cooking.

Prediction of Venous Trans-Stenotic Pressure Gradient Using Shape Features Derived From Magnetic Resonance Venography in Idiopathic Intracranial Hypertension Patients

  • Chao Ma;Haoyu Zhu;Shikai Liang;Yuzhou Chang;Dapeng Mo;Chuhan Jiang;Yupeng Zhang
    • Korean Journal of Radiology
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    • v.25 no.1
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    • pp.74-85
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    • 2024
  • Objective: Idiopathic intracranial hypertension (IIH) is a condition of unknown etiology associated with venous sinus stenosis. This study aimed to develop a magnetic resonance venography (MRV)-based radiomics model for predicting a high trans-stenotic pressure gradient (TPG) in IIH patients diagnosed with venous sinus stenosis. Materials and Methods: This retrospective study included 105 IIH patients (median age [interquartile range], 35 years [27-42 years]; female:male, 82:23) who underwent MRV and catheter venography complemented by venous manometry. Contrast enhanced-MRV was conducted under 1.5 Tesla system, and the images were reconstructed using a standard algorithm. Shape features were derived from MRV images via the PyRadiomics package and selected by utilizing the least absolute shrinkage and selection operator (LASSO) method. A radiomics score for predicting high TPG (≥ 8 mmHg) in IIH patients was formulated using multivariable logistic regression; its discrimination performance was assessed using the area under the receiver operating characteristic curve (AUROC). A nomogram was constructed by incorporating the radiomics scores and clinical features. Results: Data from 105 patients were randomly divided into two distinct datasets for model training (n = 73; 50 and 23 with and without high TPG, respectively) and testing (n = 32; 22 and 10 with and without high TPG, respectively). Three informative shape features were identified in the training datasets: least axis length, sphericity, and maximum three-dimensional diameter. The radiomics score for predicting high TPG in IIH patients demonstrated an AUROC of 0.906 (95% confidence interval, 0.836-0.976) in the training dataset and 0.877 (95% confidence interval, 0.755-0.999) in the test dataset. The nomogram showed good calibration. Conclusion: Our study presents the feasibility of a novel model for predicting high TPG in IIH patients using radiomics analysis of noninvasive MRV-based shape features. This information may aid clinicians in identifying patients who may benefit from stenting.

Psychometric testing of the Chinese version of the Perinatal Infant Care Social Support tool: a methodological study

  • Feiyan Yi;Sukhee Ahn;Miyeon Park
    • Women's Health Nursing
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    • v.30 no.2
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    • pp.128-139
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    • 2024
  • Purpose: This study aimed to translate the Perinatal Infant Care Social Support (PICSS) instrument into Chinese and to verify the reliability and validity of the translated version. Methods: This study used a cross-sectional design to examine the reliability and validity of the Chinese version of the PICSS (C-PICSS). A cohort of 150 first-time mothers in China participated, attending hospital follow-up care at 6 weeks postpartum. Data were collected after obtaining informed consent from the mothers. Results: The majority of mothers were aged between 20 and 29 years, with a mean age of 26.25 (±3.90) years. An item analysis of the 19 items in the C-PICSS showed that all items had an item-total score correlation above 0.2. This resulted in a Kaiser-Meyer-Olkin value of 0.92 and a significant Bartlett's test of sphericity (χ2=1,778.65, p<.001), confirming the suitability of the data for factor analysis. Correlation analyses revealed a strong positive relationship between infant care social support and general social support (r=.62, p<.001), and a negative relationship between infant care social support and postpartum depression (r=-. 38, p<.001). Higher scores for infant care social support were associated with reporting positive relationships with their husbands (t=3.72, p<.001) and high levels of spousal involvement (t=4.09, p<.001). In terms of structural support, spouses were identified as the primary source. Conclusion: The research results indicate that C-PICSS is reliable and valid as an indicator of social support for infant care among Chinese mothers.

A Study on Nursing Needs of Patients in the Recovery Room (회복실 환자의 간호요구도에 관한 연구 - 일 종합병원을 중심으로 -)

  • Kim Eun-Kyoung;Chae Soon-Ok;Kwon Kun-Sook;Kim Yun-Jeung;Hong Mun-He;Kim Me-Hee;Kim Nam-Sun;Lee Kyu-Eun
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.9 no.1
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    • pp.86-100
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    • 2002
  • Purpose: The purpose of the study was done to identify the nursing care needs of patients in the recovery room. Method: The subjects in this study were 127 patients in a recovery room between 6/9/2001 and 24/9/2001. The instrument used for this study was the descriptive questionnaire developed by Shin Hyun-Jin (1999). The data was analysed by frequency, percentage, mean, standard deviation, t-test, ANOVA, and factor analysis using the SPSS program. Result: 1) Kaiser - Meyer -O1kin sample appropriateness was 799 and Bartlett's test of sphericity significant probability was .000. 2) The mean score for nursing care need of patients in the recovery room was $4.17{\pm}.51$ of a total possible score of 5. The score of nursing need for different parameters was as follows : Educational need ($4.31{\pm}.49$), physical need ($4.27{\pm}.47$), emotional need ($4.11{\pm}.52$), environmental need ($3.99{\pm}.56$). 3) Differences in the needs for nursing care according to the demographics were significant for gender, marital status, operation experience, and departments consulted. General characteristic variables significantly related to nursing need were as follows: Physical need significantly related to the departments consulted (F=2.23, p=.036). Educational need significantly related to the marital status (F=2.55. p=.012), departments consulted (F=2.30, p= 031). Emotional need significantly related to the marital status (F=2.22, p=.028). Environmental need significantly related to the gender (t=-2.44, p= .016), marital status (F=2.01, p= .046). operation experience (t=-1.99. p= .048). Conclusion: Nursing care needs of patients in the recovery room are significantly related to educational need, physical need, emotional need and environmental need. Intervention plans and program need to be developed to improve strategies to meet nursing needs of patients in the recovery room.

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