1.In vitro evaluation of the bond strength between various ceramics and cobalt-chromium alloy fabricated by selective laser sintering.
Eun Jeong BAE ; Hae Young KIM ; Woong Chul KIM ; Ji Hwan KIM
The Journal of Advanced Prosthodontics 2015;7(4):312-316
PURPOSE: This study aimed to present the clinical applicability of restorations fabricated by a new method, by comparing the bond strength of between ceramic powder with different coefficient of thermal expansion and alloys fabricated by Selective laser sintering (SLS). MATERIALS AND METHODS: Fifty Co-Cr alloy specimens (25.0 x 3.0 x 0.5 mm) were prepared by SLS and fired with the ceramic (8.0 x 3.0 x 0.5 mm) (ISO 9693:1999). For comparison, ceramics with different coefficient of thermal expansion were used. The bond strength was measured by three-point bending testing and surfaces were observed with FE-SEM. Results were analyzed with a one-way ANOVA (alpha=.05). RESULTS: The mean values of Duceram Kiss (61.18 +/- 6.86 MPa), Vita VM13 (60.30 +/- 7.14 MPa), Ceramco 3 (58.87 +/- 5.33 MPa), Noritake EX-3 (55.86 +/- 7.53 MPa), and Vintage MP (55.15 +/- 7.53 MPa) were found. No significant difference was observed between the bond strengths of the various metal-ceramics. The surfaces of the specimens possessed minute gaps between the additive manufactured layers. CONCLUSION: All the five powders have bond strengths higher than the required 25 MPa minimum (ISO 9693); therefore, various powders can be applied to metal structures fabricated by SLS.
Alloys*
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Ceramics*
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Fires
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Powders
2.Preliminary results of nutritional intervention by digestive ferments of seed germ powder in combining with available local food on children of the age of combined feeding in Thanh Hoa
Journal of Practical Medicine 2003;439(1):3-4
Malnutrition status of children from 0 to 60 months of age in two agricultural communes in Thanh Hoa province from July 20 to October 20/2000 was investigated. The indicatior of weigh/age shows a rate of 54% of malnutrition. In graphic this rate increases dramatically in the period of 23-34 months of age, the highest is in 25-36 months of age. Digestive ferment Aplaza, a functional food, in combining with local available source of food improved significantly the nutritional state and prevented this malnutritional condition. This is an eligible way of high efficacy to strengthen the awareness and the practice of nutrition, aiding the poor population in rural area
Nutrition Therapy
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Powders
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Child
3.A COMPARATIVE STUDY OF THE PHYSICOCHEMICAL PROPER TIES AND BOND STRENGTH TO METAL BETWEEN THE REGULAR OPAQUE POWDER AND CORE POWDER.
Jang Seop LIM ; Chang Mo CHUNG ; Young Chan JEON
The Journal of Korean Academy of Prosthodontics 1997;35(1):144-164
The purpose of this study were to investigate the chemical composition, mean particle size, linear thermal expansion coefficient and metal-bonding strength of the regular opaque powder and core powder. In this study, 4 types of ceramic powders, namely Duceram Jacket Opaque powder, Duceram Opaque powder, Vita Hi-Ceram powder, Vita VMK Paint On-88 powder were used. Chemical composition was evaluated by EDS(Energy Dispersive X-ray Spectrophotometer, Oxford QX-2000, England), particle size was measured by MALVERN Instruments(MALVERN Instruments SB. OC., U.S.A.) ad linear thermal expansion coefficient was measured by dilatometer(Motoyama, Japan). Bond strength was measured by the Universal tsting machine(Istron Co., Ltd., U.S.A.). The Results were as follows : 1. Through recognition of the relative difference in chemical composition between the core powder and the regular opaque powder, the difference in the proportion of Al2O3 in each type of material is demonstrated ; Duceram Jaket Opaque powder : 30.16%, Duceram Opaque powder : 16.60%, Vita Hi-Ceram : 63.64%, Vita VMK Paint-On 88 : 16.16%. 2. There was no significant difference in the proportion of metal-bonding materials between the core powder and the regular opaque powder. 3. In the regular opaque powder, alkaline materials were incoporated in order to increase the coefficient of thermal expansion. 4. In the particle size analysis, there was no significant difference in mean particle size or in the particle size distribution between the core powder and the regular opaque powder. 5. In the thermal expansion test for temperature range of 25~600degrees C, the regular opaque powder had higher coefficient of thermal expansion than that of core powder. 6. In the 4 point flexural bending test, there was no statistically significant difference in the mean bond strength between the core powder and the opaque powder among the Duceram products.
Ceramics
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Paint
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Particle Size
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Powders
4.Application of design technology for preparing Lingzhu Powder particles based on solvent evaporation method.
Xiao ZHOU ; Liang FENG ; Xiao-Fei ZHANG ; Yan-Jun YANG ; Xiao-Bin JIA ; Jun-Bo ZOU ; Ya-Jun SHI
China Journal of Chinese Materia Medica 2021;46(23):6028-6034
Targeting the deficiencies of Lingzhu Powder, this study introduced the particle design technology to improve its quality. Based on the mechanism of particle design for powder and the characteristics of solvent evaporation method, composite particles consisting of Succinum, Cinnabaris, and artificial Bovis Calculus were prepared. And the powder properties of composite particles and physical mixtures as well as the content uniformity of toxic components were investigated for exploring the technological advantages of particle design in improving the quality of Lingzhu Powder. The results showed that the composite particles prepared using solvent evaporation method and particle design technology were micro-particles, and the stable agglomerate structure could be observed under SEM. Composite particles exhibited better fluidity and compliance in oral intake than physical mixtures. The differences in chromatism, bulk density, and content uniformity of the composite particles were smaller than those of physical mixtures, and the corresponding RSD values \[4.8%, 1.8%, 3.4%(bilirubin), and 0.63%(HgS), respectively\] were smaller. The solvent evaporation combined with particle design technology can be utilized to significantly improve the quality of Lingzhu Powder, which has provided new ideas for the optimization of the quality of traditional Chinese medicinal powder.
Particle Size
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Powders
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Solvents
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Technology
5.The effect of powder A2/powder A3 mixing ratio on color and translucency parameters of dental porcelain.
Wan Sun LEE ; So Yeon KIM ; Ji Hwan KIM ; Woong Chul KIM ; Hae Young KIM
The Journal of Advanced Prosthodontics 2015;7(5):400-405
PURPOSE: The purpose of this study is to mix dental ceramic powder in varying ratios and evaluate the effect of the mixing ratio on color and translucency. MATERIALS AND METHODS: The ceramic powder of shade A3 of the same product was mixed with the shade A2 of three products: IPS e.max Ceram (Ivoclar Vivadent, Schaan, Liechtenstein), Vintage Halo (SHOFU Inc., Kyoto, Japan), and Ceramco 3 (Ceramco-Dentsply, Burlington, NJ, USA) in the following fixed ratios (0 wt%, 25 wt%, 50 wt%, 75 wt%, and 100 wt%) and then fired. A total of 150 specimen of ceramic fired were manufactured in a regular size (W: 8.5 mm, L: 10.5 mm, and H: 1.5 mm). For color and translucency, L*, a*, and b* were measured and Two-way analysis of variance (ANOVA) and One-way analysis of variance (ANOVA) were used for data analysis (alpha=0.05). RESULTS: The higher the mixing ratio was, L*, a*, and b* of IPS e.max Ceram were all increased, and L* of Vintage Halo was reduced and a* and b* were increased. L* and a* of Ceramco3 were reduced and b* of Ceramco3 was increased. Color difference (DeltaE*ab) was increased in all three products as the mixing ratio got higher. Increased mixing ratios resulted in decreased translucency parameter (TP) values for IPS e.max Ceram but increased TP values for Vintage Halo and Ceramco3. CONCLUSION: In this limited study, CIE L*, a*, and b* were influenced by the mixing ratio of the A3 powders and porcelain powder mixtures represented a various color and translucency.
Ceramics
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Dental Porcelain*
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Fires
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Powders
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Statistics as Topic
6.Study on benchmark preparation technology of boiled and powdered classical prescriptions by taking Houpo Wenzhong Decoction as an example.
Ju-Yuan LUO ; Gong-Sen CHEN ; Dong-Han LIU ; Yu-Jia MO ; Xiang-Long YU ; Shou-Ying DU ; Jie BAI ; Yang LU ; Yu-Ming WANG ; Cun LIU
China Journal of Chinese Materia Medica 2019;44(18):3994-3999
In recent years,the development and application of classical famous prescriptions have attracted much attention. However,the differences between ancient and modern conditions lead to difficulties in carrying out practical work. In this paper,with Houpu Wenzhong Decoction as an example,the key technologies of boiling granularity,water addition,boiling time and sample pretreatment methods were investigated on the basis of sufficient literature research. The experimental results showed that there was no significant difference in the concentration of index components between those with different granularity( 2 mm and 3-5 mm) and different decocting time( 30 min and 60 min),but the extraction rate of index components was relatively high when the granularity of powder was 2 mm and decocting time was 30 min. With the increase of water content,the concentration of index components and the extraction rate were increased in varying degrees. A certain proportion of methanol aqueous solution was used as the resolvent before content determination of the reference sample of Houpu Wenzhong Decoction,which could take into account both the spectral information of water-soluble components and fat-soluble components in the prescription,and help to display the overall information of the prescription' s chemical components more comprehensively. At the same time,the boiling and dispersing classical prescriptions in the Catalogue of Ancient Classical Prescriptions( the first batch) were collected and summarized in this study; the key influencing factors of decocting process were analyzed from different angles,and preliminary research suggestions were put forward,so as to provide a certain direction and reference for the establishment of quality standard of Houpu Wenzhong Decoction,as well as for the development,research and clinical application of boiling and dispersing classical prescriptions.
Drugs, Chinese Herbal/standards*
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Powders
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Prescriptions
7.Discrete element simulation study of mixing process of Guizhi Fuling Capsules: parameter calibration.
Huan-Zheng LI ; Xue-Fang TANG ; Yu LIN ; Fang-Fang XU ; Xin ZHANG ; Hui-Qing YE ; Wei XIAO ; Zhen-Zhong WANG ; Bing XU
China Journal of Chinese Materia Medica 2023;48(15):4007-4014
The mixing process is a critical link in the formation of oral solid preparations of traditional Chinese medicine. This paper took the extract powder of Guizhi Fuling Capsules and Paeonol powder as research objects. The angle of repose, loose packing density, and particle size of the two powders were measured to calibrate discrete element simulation parameters for the mixing process. The discrete element method was used to calibrate the simulated solid density of Paeonol powder and extract powder of Guizhi Fuling Capsules based on the Hertz-Mindlin with JKR V2 contact model and particle scaling. The Plackett-Burman experimental design was used to screen out the critical contact parameters that had a significant effect on the simulation of the angle of repose. The regression model between the critical contact parameters and the simulated angle of repose was established by the Box-Behnken experimental design, and the critical contact parameters of each powder were optimized based on the regression model. The best combination of critical contact parameters of the extract powder of Guizhi Fuling Capsules was found to be 0.51 for particle-particle static friction coefficient, 0.31 for particle-particle rolling friction coefficient, and 0.64 for particle-stainless steel static friction coefficient. For Paeonol powder, the best combination of critical contact parameters was 0.4 for particle-particle static friction coefficient and 0.19 for particle-particle rolling friction coefficient. The best combination of contact parameters between Paeonol powder and extract powder of Guizhi Fuling Capsules was 0.27 for collision recovery coefficient, 0.49 for static friction coefficient, and 0.38 for rolling friction coefficient. The verification results show that the relative error between the simulated value and the measured value of the angle of repose of the two single powders is less than 1%, while the relative error between the simulated value and the measured value of the angle of repose of the mixed powder with a mass ratio of 1∶1 is less than 4%. These research results provide reliable physical property simulation data for the mixed simulation experiment of extract powder of Guizhi Fuling Capsules and Paeonol powder.
Wolfiporia
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Calibration
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Powders
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Medicine, Chinese Traditional
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Capsules
8.Quality value transmitting of volatile components in personalized preparations:a case study of Menthae Haplocalycis Herba.
Yi-Ping LI ; Yan-Long HONG ; Lan SHEN ; Yi FENG ; Xiao LIN ; You-Jie WANG
China Journal of Chinese Materia Medica 2021;46(15):3780-3788
Considering the characteristic chromatograms and quality value transmitting of three volatile components, this study investigated the changes in volatile components of Menthae Haplocalycis Herba in each heating process of personalized preparations and identified the critical control points for the application of volatile components from traditional Chinese medicine in such preparations. The characteristic chromatograms of volatile components in Menthae Haplocalycis Herba were established by gas chromatography, followed by the quantitative determination of three volatile components menthone, menthol, and piperitone and the comparison of retention rates of volatile components during the crushing, extraction, concentration and drying of preparation products and their change rules in characteristic peaks. The results showed that the volatile components of Menthae Haplocalycis Herba were reduced in each process. The loss rate was low in the crushing process when the volatile component peaks were present, but high in the extraction and concentration processes, manifested as the absence of partial component peaks and the presence of new component peaks. The changes in volatile components of Chuanxiong Chatiao Granule in the drying process were compared with those in Chuanxiong Chatiao Pill, both of which were prepared from the raw Menthae Haplocalycis Herba powder, and the findings demonstrated that Chuanxiong Chatiao Pill was superior to Chuanxiong Chatiao Granule. This study confirmed that the retention rates of volatile components in Menthae Haplocalycis Herba were mostly affected by the extraction and concentration processes, and the packing of preparations helped to reduce the loss of volatile components in Menthae Haplocalycis Herba powder, which has provided reference for the application of Chinese medicinal materials containing volatile components in the personalized preparations.
Drugs, Chinese Herbal
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Medicine, Chinese Traditional
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Powders
9.Development of Intelligent Multifunctional Knee Joint Functional Exercise Equipment.
Haoyu CHEN ; Dongliang ZHAO ; Na LI
Chinese Journal of Medical Instrumentation 2022;46(5):503-508
OBJECTIVE:
Develop an intelligent equipment that can perform multiple modes of functional exercise on the knee joint, and can accurately measure and control strength, angle, angular velocity, time, frequency and so on.
METHODS:
Using geared motors, magnetic powder brakes and synchronous belt wheel sets and other mechanical structure and transmission technology combined with sophisticated mechanical design methods, the knee joint multiple functional exercise methods are cleverly integrated; a highly reliable PLC is used as the control core; the resistance torque out-put by the equipment is accurately controlled by adjusting the size of the exciting current; the angle sensor is used to accurately measure the rotation angle around the axis; and the error of each parameter index and the actual measured value is controlled within 5%.
RESULTS:
The developed prototype has a compact structure and a simple and convenient method of use. Based on the control of joint parameters such as resistance, the expected goal is achieved.
CONCLUSIONS
The equipment can carry out diversified, accurate and automatic rehabilitation treatment for knee joint diseases, and has certain social and economic benefits.
Biomechanical Phenomena
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Knee Joint
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Powders
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Rotation
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Torque
10.Particle design for improving content uniformity of Hewei Jiangni Capsules.
Wei MEI ; Liang FENG ; Ya-Jun SHI ; Jun-Bo ZOU ; Xiao-Fei ZHANG ; Zong-Ping ZHAO ; Dong-Yan GUO ; Xiao-Bin JIA
China Journal of Chinese Materia Medica 2021;46(23):6045-6052
Targeting the poor powder characteristics of the contents in Hewei Jiangni Capsules, this study characterized the powder properties of the contents and employed particle design technique for improving the content quality. The content composite particles of Hewei Jiangni Capsules prepared by the particle design technique were evaluated by scanning electron microscopy(SEM), followed by infrared ray(IR), content uniformity, and in vitro dissolution detection. It was found that there was a good correlation between the crushed particle size of slices and the crushing time, and the calcined Haematitum was responsible for the poor content uniformity. After the fine powder of calcined Haematitum was super-finely ground for 8.5 min and those of the other contents in the capsule for 1 min, they were prepared into the composite particles, whose property characterizations were compared with those of the physical mixtures. The content uniformity of the prepared composite particles was significantly improved, and the preparation process was stable and reliable. The adoption of particle design technology to correct the poor uniformity of the physical mixture, solve the pharmaceutical defects of Hewei Jiangni Capsules, and improve the quality of prescriptions has provided important reference for the clinical application and development of Chinese medicinal preparations.
Capsules
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Microscopy, Electron, Scanning
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Particle Size
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Powders