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Developing a novel radial ultrasonic vibration-assisted grinding device and evaluating its performance in machining PTMCs

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Chinese Journal of Aeronautics 2023年第7期36卷 244-256页

作者： Biao ZHAO bangfu wu Yansong YUE Wenfeng DING Jiuhua XU Guoqiang GUO National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China Shanghai Spaceflight Precision Machinery Institute Shanghai 201600China

Particle-reinforcing titanium matrix composites(PTMCs)exhibit the sharp raising applications in modern industries owing to its extraordinary physical and mechanical ***,the poor grindability and unstable grinding processes due to the existence of TiC particles and TiB short fibres inside PTMCs,leading to the sudden grinding burn and low material removal *** this work,a novel radial ultrasonic vibration-assisted grinding(RUVAG)device with a special cross structure was developed to improve machining efficiency and avoid grinding ***,the resonant modal and transient dynamic characteristics of radial ultrasonic vibration system were *** grinding performance experiments were then conducted under the conventional grinding(CG)and RUVAG using mono-layer cubic boron nitride abrasive wheels,in views of the grinding forces and force ratio,grinding temperature,and ground surface *** show that the ultrasonic vibration direction can be transformed effectively using the special cross structure of vibration converter,and better vibration homogeneity can be *** has a smaller tangential grinding force by 5.0%–17.2%than that of CG,but a higher normal grinding force of 6.5%–14.9%,owing to the periodic impact of grinding *** addition,RUVAG possesses a remarkable lower grinding temperature in range of 24.2%–51.8%and a higher material removal rate by 2.8 times compared with CG,resulting from the intermittent cutting behavior between the grinding wheel and *** this case,the sudden burn can be avoided during high-speed grinding ***,the proportion of micro-fracture defects on machined surface is slightly increased once the ultrasonic vibration mode is employed because of the periodic impact on reinforced particles,whereas the pull-out defects of reinforced particles are reduced significantly.

关键词： Grinding force Grinding temperature Ground surface morphology Particle-reinforcing titanium matrix composites Radial ultrasonic vibrationassisted grinding

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Molecular adsorbent recirculating system in dealing with maternal Amanita poisoning during the second pregnancy trimester: a case report

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Hepatobiliary & Pancreatic Diseases International 2004年第1期3卷 152-154页

作者： bangfu wu MinMin Wang Department of Gastroenterology Guangzhou 12th Municipal People's Hospital China.

BACKGROUND:A 27-year-old woman in her 20th week of pregnancy was hospitalized because of food poisoning caused by Amanita phalloides.;METHODS:Previously extracorporeal purification treatments with 2 times of hemodialysis plus hemoperfusion and a high volume therapeutic plasma exchange (PE) in addition to intensive medication during the first 8 days failed to improve hepatic encephalopathy (HE) and liver function but developed deep coma with severe blood chemistry and signs of threatened abortion.;RESULTS:Treatments with intermittent molecular adsorbent recirculating system (MARS) for 3 times resulted in an immediate improvement of liver function and clinical symptoms including HE and threatened abortion until her fully recovery. When the life-threatening maternal illness was cured gestation went on until premature birth at the 36th week of pregnancy, and the infant underwent an undisturbed development.;CONCLUSIONS:MARS method appears to be an optimal therapy for patients with acute liver failure secondary to cytoxic mushroom poisoning during pregnancy.

关键词： molecular adsorbent recirculating system Amanita mushroom poisoning pregnancy

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Grinding Characteristics of MoS_(2)-Coated Brazed CBN Grinding Wheels in Dry Grinding of Titanium Alloy

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 43-55页

作者： Junshuai Zhao Biao Zhao Wenfeng Ding bangfu wu Ming Han Jiuhua Xu Guoliang Liu National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing 210016China AECC Zhongchuan Transmission Machinery Co. LtdChangsha 410200China

As an important green manufacturing process,dry grinding has problems such as high grinding temperature and insufficient cooling *** at the problems of sticking and burns in dry grinding of titanium alloys,grinding performance evaluation of molybdenum disulfide(MoS_(2))solid lubricant coated brazed cubic boron carbide(CBN)grinding wheel(MoS_(2)-coated CBN wheel)in dry grinding titanium alloys was carried *** lubrication mechanism of MoS_(2)in the grinding process is analyzed,and the MoS_(2)-coated CBN wheel is *** results show that the MoS_(2)solid lubricant can form a lubricating film on the ground surface and reduce the friction coefficient and grinding *** the experimental parameters,normal grinding force decreased by 42.5%,and tangential grinding force decreased by 28.1%.MoS_(2)lubricant can effectively improve the heat dissipation effect of titanium alloy grinding arc *** with common CBN grinding wheel,MoS_(2)-coated CBN wheel has lower grinding *** the grinding depth reaches 20μm,the grinding temperature decreased by 30.5%.The wear of CBN grains of grinding wheel were analyzed by mathematical statistical ***_(2)lubricating coating can essentially decrease the wear of grains,reduce the adhesion of titanium alloy chip,prolong the service life of grinding wheel,and help to enhance the surface quality of *** research provides high-quality and efficient technical support for titanium alloy grinding.

关键词： Titanium alloy Dry grinding MoS_(2)-coated CBN wheel Grinding wheel wear

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Shotgun lipidomic analysis of simple lipids in rapeseed oil by electrospray ionization tandem mass spectrometry

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Oil Crop Science 2018年第4期3卷 247-257页

作者： Xin Lv Fang Wei Shuling Xu Ya Xie bangfu wu Zongyuan wu Xuyan Dong Hong Chen Oil Crops Research Institute Chinese Academy of Agricultural Sciences Key Laboratory of Oil seeds processing Ministry of Agriculture-Hubei Key Laboratory of Lipid Chemistry and Nutrition

Rapeseed is widely grown in China as an important oil crop. In this study, Shotgun lipidomic methodology based on tandem mass spectrometry but without liquid chromatography was established for simple lipids analysis such as mono-, di-and triacylglycerols(MAGs, DAGs and TAGs) and the derivatives such as free fatty acids(FFAs). Six varieties of rapeseeds belonging to 3 types(B. juncea, B. campestris and B. oleracea) from different areas of China were investigated, with 59 TAG species, 10 DAG species, 5 MAG species and 6 FFA species identified. It was found that erucic acid was mainly present in the form of TAG 62:4(22:1/18:2/22:1), TAG 62:3(22:1/18:1/22:1), and TAG 62:5(22:1/18:3/22:1) in high erucic acid rapeseed oils, while oleic acid was mainly present in the form of TAG 54:2(18:0/18:1/18:1), and TAG 54:4(18:1/18:2/18:1) in high oleic acid rapeseed oils. It was difficult for DAG, MAG and FFA quantification due to their low content with high background content of TAGs. Results showed that the main differences in lipids were not derived from the types of rapeseed, but directly related to varieties.

关键词： shotgun lipidomic TAGs DAGs MAGs FFAs rapeseed oil

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Importance of quality control in lipidomics profiling based on mass spectrometry

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Oil Crop Science 2017年第4期2卷 217-224页

作者： Ya Xie Huifang Ma Fang Wei Xin Lyu Zongyuan wu bangfu wu Shuling Xu Xuyan Dong Hong Chen Fenghong Huang Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences Key Laboratory of Oilseeds Processing of Ministry of Agriculture Key Laboratory of Biology and Genetic Improvement of Oil Crops of Ministry of Agriculture P. R.China Hubei Key Laboratory of Lipid Chemistry and Nutrit

As a current analytical instrument for lipidomics profiling with high sensitivity, selectivity, and throughput, mass spectrometry (MS) has been widely used in the field of clinical medicine, nutrition, bromatology, botany and etc. During the routine use of shotgun- MS and high performance liquid chromatography-MS (HPLC-MS) in lipid analysis, an important problem to be solved is the defective repeatability and stability resulting from signal attenuation or drifts in LC-peak shape and retention time of MS platform. To remove or minimize the influence, extensively accepted and applied QC (quality control) samples must be performed. In this review, we emphasize the importance of the application of QC samples, which could 1) provide the ability to equilibrate the analytical platform at the beginning; 2) act as a quality assurance (QA) procedure during the analytical process; 3) perform signal correction in the data handling with the purpose of reducing analytical variation and improving the precision of quantitative analysis; 4) the data between different laboratories can be compared through the incorporation of particular QC samples-Standard Reference Material (SRM) 1950. In addition, we display 4 types and requirements of QC samples during quality control in lipidomics profiling. Lipidomics profiling based on MS strongly requires commonly accepted guidelines for quality control to perform routine, large-scale researches, so as to integrate data from different scientists for more information.

关键词： quality control lipidomics mass spectrometry correction standardization

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Impact of feeding flaxseed and microalgal residue on omega-3 fatty acids enrichment in hen eggs

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Oil Crop Science 2017年第4期2卷 265-271页

作者： bangfu wu Xuyan Dong Fang Wei Jiqian Xiang Siew Young Quek Xin Lyu Lin Zhu Hong Chen Institute of Oil Crops Research Chinese Academy of Agricultural Sciences Key Laboratory of Oilseeds processing Ministry of Agriculture - Hubei Key Laboratory of Lipid Chemistry and Nutrition Wuhan China Enshi Autonomous Prefecture Academy of Agricultural Sciences Enshi China School of Chemical Sciences University of Auckland Auckland 1142 New Zealand

To investigate the impact of dietary supplementation of different omega-3 polyunsaturated fatty acids (n-3 PUFAs) resources on PUFAs enrichment in hen eggs, two supplemental materials, flaxseed and oil-extracted microalgal residue of heterotrophic Schizochytrium, were added to the diet of laying hens in 3 groups. Results showed that supplementation with flaxseed and Schizochytrium residue gave rise to the increased, but different n-3 PUFAs levels in egg yolk, mainly α-linolenic acid (ALA) and docosahexaenoic acid (DHA). The ratio of n-6/n-3 PUFAs was reduced in all groups. After 14 days feeding of supplied PUFAs resources, n-3 PUFAs contents reached a plateau, and then remained constant during further supplementation in 3 experimental groups. Both the highest ALA level and DHA level were achieved in flaxseed group and microalgae group, reaching up to 353.69 (±68.15) mg/egg and 301.41 (± 26.76) mg/egg respectively. Moreover, the n-3 PUFAs enrichment efficiency was relatively low in flaxseed group when compared to other 2 groups. Laying rates of hens before entering peak production period could be improved by adding flaxseed but was not obviously affected by Schizochytrium residue. The egg weight, on the other hand, had no relationship with dietary supplementation. Thus, supplementation of flaxseed or Schizochytrium residue into standard feed offers an alternative choice for the production of n-3 PUFAs enriched eggs.

关键词： n-3 PUFAs enrichment hen eggs flaxseed microalgal residue

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Microencapsulation of nutmeg essential oil by spray-drying with different wall materials

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Oil Crop Science 2018年第4期3卷 258-269页

作者： Xuyan Dong bangfu wu Qianchun Deng Fang Wei Hong Chen Chen Yang Renhuai Cong Chayan Wan Xin Lv Fenghong Huang Key Laboratory of Oilseeds processing Ministry of Agriculture-Hubei Key Laboratory of Lipid Chemistry and Nutrition Oil Crops Research Institute Chinese Academy of Agricultural Sciences Infinitus China Ltd.Co.

Nutmeg essential oil with volatile components is sensitive to oxygen, light, water and high temperature. Spray-drying is widely used as an encapsulation technique for improving compound stability during processing and storage. In this study, influence of encapsulated matrix on spray-dried nutmeg essential oil microcapsule was investigated using blends of maltodextrin and either gum Arabic(GA-MD), or octenyl succinic acid modified starch(OSA-MD) as wall materials. Characteristics of spray-dried powders from these 2 wall materials were evaluated and compared. Powder property analysis indicated that GA-MD microcapsules presented larger size, higher moisture and poorer flowability compared with OSA-MD microcapsules. Fourier transforms infrared spectroscopy and thermogravimetric analysis showed that both GA-MD and OSA-MD microcapsules improved the stability of nutmeg essential oil. However, GA-MD microcapsules exhibited higher storage stability than OSA-MD microcapsules. This research provided theoretical foundation for wall material choice of microcapsule and nutmeg essential oil utilization in food industry.

关键词： nutmeg essential oil microcapsule spray-drying powder property storage stability

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颗粒增强钛基复材轴向超声振动辅助磨削试验研究

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航空制造技术 2021年第11期64卷 96-102页

作者：吴帮福丁文锋曹洋南京航空航天大学南京210016

针对颗粒增强钛基复合材料(PTMCs)磨削加工过程中磨削温度高、表面质量差、加工效率低及砂轮使用寿命短等问题,在传统磨削加工的基础上引入了超声复合加工技术。开展了普通磨削和超声磨削PTMCs材料对比试验,研究了磨削工艺参数对磨削力... 详细信息

针对颗粒增强钛基复合材料(PTMCs)磨削加工过程中磨削温度高、表面质量差、加工效率低及砂轮使用寿命短等问题,在传统磨削加工的基础上引入了超声复合加工技术。开展了普通磨削和超声磨削PTMCs材料对比试验,研究了磨削工艺参数对磨削力、表面粗糙度以及显微硬度的影响规律,并深入地分析了超声振动的影响机制。结果表明,超声振动可显著地降低磨削力,法向磨削力降低了11.7%~20.1%,切向磨削力降低了9%~19%。随着材料去除率的增大,加工表面质量逐渐变差,但超声磨削表面粗糙度小于普通磨削,主要是与超声振动改变了砂轮的自锐性能和磨粒运动轨迹有关。此外,由于超声振动降低了磨削力和磨削温度,因此使得超声磨削在一定程度上可抑制磨削烧伤,降低加工表面显微硬度,改善加工表面裂纹缺陷。

关键词：颗粒增强钛基复合材料超声磨削最大未变形切屑厚度磨削力表面粗糙度

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