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负载陈皮提取物的w/O/w型乳液的制备及其性能评价

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食品工业科技 2024年

作者：王庭雨沈飞赵佳伟吴振强华南理工大学生物科学与工程学院江门市泛亚生物工程与健康研究院益为益生物制造(江门)有限公司

为提高陈皮提取物（Chenpi extract， CPE）中的活性成分的封装稳定性及生物可及性，本研究以柑渣可溶性膳食纤维-明胶（Citrus soluble dietary fiber-gelatin， CSDF-G）复合物和聚蓖麻酸甘油酯作为乳化剂制备了负载CPE的w1/O/w2双重... 详细信息

为提高陈皮提取物（Chenpi extract， CPE）中的活性成分的封装稳定性及生物可及性，本研究以柑渣可溶性膳食纤维-明胶（Citrus soluble dietary fiber-gelatin， CSDF-G）复合物和聚蓖麻酸甘油酯作为乳化剂制备了负载CPE的w1/O/w2双重乳液，并探究了CSDF-G复合物和w1/O/w2双重乳液最佳制备条件、乳液环境耐受性以及体外消化特性。结果显示CSDF和G通过非共价静电作用相互结合，并且在pH 3.5条件下结合效果最佳，形成的复合物乳化能力最强。当CSDF/G比例为3:1（w/w）、CSDF-G复合物总浓度为2%（w/v）、w1/O和w2比例为3:7（v/v）时，制备的w1/O/w2双重乳液分布均匀，粒径最小，粘弹性最强，多酚和黄酮的封装率分别达到96.82%和90.08%。此外，该条件下制备的乳液不仅在pH 3.0-5.0和离子强度0-100 mmol/L的环境下保持了较好的稳定性，同时还对高温和紫外光照环境展现出较强的耐受能力。体外模拟消化结果表明，乳液的双重结构在胃肠道消化过程中被缓慢破坏。经肠道消化后，乳液负载的CPE的多酚生物可及性较游离大豆油负载的CPE提高了33.22%。上述结果表明本研究制备的w1/O/w2双重乳液具有良好的活性成分递送潜力，研究结果为新型陈皮相关功能产品的开发提供了参考。

关键词：陈皮提取物柑渣可溶性膳食纤维-明胶复合物 w /O/w 双重乳液环境耐受性生物可及性

Electronic structures and physical properties of pure Cr,Mo and w

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中国有色金属学会会刊：英文版 2003年第5期13卷 1102-1107页

作者：谢佑卿邓永平刘心笔 School of Materials Science and Engineering Central South University Changsha 410083China

Using the one atom theory, the electronic structures of pure Cr, Mo and w with bcc structure were determined respectively as: [Ar] (3d c) 3.32 (3d n) 2.26 (4s c) 0.25 (4s f) 0.17 , [Kr] (4d c) 4.23 (4d n) 1.48 (5s c) 0.02 (5s f) 0.27 and [Xe](5d c) 5.16 (6s c) 0.25 (6s f) 0.59 .The electronic structures of these metals with hcp and fcc structures and liquid state were also studied. According to their electronic structures, the relationship between the electronic structure and crystalline structure was explained qualitatively and the relationship between the difference of mechanical properties and transport properties of pure Cr, Mo and w with bcc structure and their electronic structures was also explained qualitatively; the lattice constants, binding energy, potential curves, elasticities and the temperature dependence of the linear thermal expansion coefficient of bcc Cr, bcc Mo and bcc w were calculated quantitatively.

关键词： Cr Mo w 铬钼钨电子结构晶体结构结合能机械性能转变特性

Separation of w and Mo from their peroxoacids solutions by thermal decomposition

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Transactions of Nonferrous Metals Society of China 2016年第10期26卷 2731-2737页

作者：张文娟李江涛赵中伟李飞中南大学冶金与环境学院长沙410083 中南大学稀有金属冶金与材料制备湖南省重点实验室长沙410083 稀有金属冶金与材料制备湖南省重点实验室长沙410083

A separation method for w and Mo from peroxoacids solution by thermal decomposition wasstudied. Thermal decomposition of peroxotungstic acid and peroxomolybdic acid was investigated respectively. The results confirmed that peroxomolybdic acid showed a preferable stability compared with peroxotungstic acid. This thermal stability difference was the basic principle of theseparationof w and Mo. Experiments were performed to study the effects of temperature, stirring speed, free acid concentration and Mo concentration on the separation efficiency. The results indicated that peroxotungstic acid decomposed into tungstic acid（H2wO4） and precipitated selectively,while Mo was rejected in aqueous solution,realizing good separation of w and Mo. The separation factorof w and Moreached 112 under the studied conditions, which indicated that this method has potential for use in separating w and Mo.

关键词： w Mo w Mo separation thermal decomposition peroxotungstic acid peroxomolybdic acid

Effect of w addition on phase transformation and microstructure of powder metallurgic Ti-22Al-25Nb alloys during quenching and furnace cooling

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Chinese Journal of Aeronautics 2019年第5期32卷 1343-1351页

作者： Junpeng YANG Qi CAI Zongqing MA Yuan HUANG Liming YU Huijun LI Yongchang LIU State Key Lab of Hydraulic Engineering Simulation and Safety School of Materials Science & Engineering Tianjin University Materials Genome Institute Shanghai University

Powder metallurgic Ti2 AlNb alloys with w addition are sintered at 900, 1000, 1070 °C,and 1150 °C(i.e., in the O + B2, a_2+ B2 + O, a_2+ B2, and single B2 phase regions, respectively)for 12 h, followed by water quenching and furnace cooling. Comparisons of phase and microstructure between quenched and furnace-cooled w-modified alloys are carried out to illustrate the phase transformation and microstructure evolution during the cooling process. Furthermore, a comparison is also made between w-modified and w-free alloys, to reveal the function of the w alloying.w addition accelerates the solutions of a_2 and O phases during the high-temperature holding, and a widmannsta¨tten B2 + O structure, which contributes to the properties, is induced by furnace cooling from all the phase regions. The widmannsta¨tten structure includes a B2 matrix, primary O, and secondary O precipitates. However, w alloying refines the widmannsta¨tten structure only when the alloys are solution-treated and then cooled from the single B2 phase. Although the hardness of the w-modified alloys is lower than that of the w-free alloys sintered in the same phase region, an enhancement of hardness, 489 ± 18 HV, is obtained in the alloy solution-treated in the single B2 phase region for only 0.5 h.

关键词： Hardness Phase formation Ti2AlNb-based alloy w addition widmannsta¨tten microstructure

Devise of a w serpentine shape tube heat exchanger in a hard chromium electroplating process

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Chinese Journal of Chemical Engineering 2019年第1期27卷 218-225页

作者： Surasit Tanthadiloke Paisan Kittisupakorn Pannee Boriboonsri Iqbal M.Mujtaba Department of Chemical Engineering Faculty of EngineeringChulalongkorn University School of Engineering University of Bradford

In a hard chromium electroplating process, a heat exchanger is employed to remove the heat produced from the high current intensity in an electroplating ***, a conventional U shape heat exchanger is installed in the bath, but it provides low heat ***, this study designs a novel w serpentine shape heat exchanger with identical heat transfer area to the conventional one for increasing heat removal *** performance of the heat exchange is tested with various flow velocities in a cross-section in range of 1.6 to 2.4 m·s^(-1).Mathematical models of this process have been formulated in order to simulate and evaluate the heat exchanger *** results show that the developed models give a good prediction of the plating solution and cooling water temperature, and the novel heat exchanger provides better results at any flow *** addition, the w serpentine shape heat exchanger has been implemented in a real hard chromium electroplating *** data collected have shown that the new design gives higher heat removal performance compared with the U shape heat exchanger with identical heat transfer area; it removes more heat out of the process than the conventional one of about 23%.

关键词： w serpentine shape Hard chromium electroplating Mathematical modeling Simulation Heat exchanger

Effects of various rare earth oxides on morphology and size of oxide dispersion strengthening(ODS)-w and ODS-Mo alloy powders

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Transactions of Nonferrous Metals Society of China 2022年第8期32卷 2665-2680页

作者： He ZHANG Zhi-bo LI Xiao-chun DENG Ben CHEN Guo-hua ZHANG Kuo-Chih CHOU State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Green Recovery and Extraction of Rare and Precious Metals University of Science and Technology BeijingBeijing 100083China

Ultrafine oxide dispersion strengthening(ODS)-Mo and ODS-w alloy powders containing different types of oxide nanoparticles were successfully synthesized by spraying method(solid−liquid mixing method)combined with the reductions with carbon black and hydrogen in *** is concluded that the solution concentration and type of rare earth oxide have no effect on the grain size of ODS-Mo alloy powder,but have obvious effect on that of ODS-w alloy *** higher the concentration of rare earth solution is,the smaller the average grain size of ODS-w alloy powder ***,compared with doping with CeO_(2),the grain sizes of reduction products of La_(2)O_(3) and Y_(2)O_(3) doped wO_(3) are relatively *** with the undoped case,there is almost no change for grain size of ODS-Mo alloy powder,while the grain size of ODS-w alloy powder becomes much *** is probably due to the appearance of the composite oxide(such as La_(2)wO_(6))formed by the reaction between tungsten oxide and rare earth oxides,which promotes the heterogeneous nucleation and growth of tungsten grains during the reduction process of ODS-w,while there is no complex oxide composed of molybdenum and rare earth oxides in the reduction process of ODS-Mo.

关键词： grain size rare earth oxide oxide dispersion strengthened alloy w Mo

Sputtering of w Mo alloy under ion bombardment

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中国有色金属学会会刊：英文版 1999年第3期9卷 629-633页

作者： Li Chengming(李成明) Tian Linhai(田林海) Xu Zhong(徐重) Taiyuan Univ Technol Res Inst Surface Engn Taiyuan 030024 Peoples R China

The distribution of plasma density in the vicinity of the w Mo alloy source in the process of double glow discharge plasma surface alloying was diagnosed using the moveable Langmuir probe. The sputtering law, surface composition and morphological variation of the w Mo alloy source was studied. The experimental results show that there exists obvious preferential sputtering on the surface of the w Mo alloy source under the argon ion bombardment; the stable period is reached after a transitional period, and the preferential sputtering occurs in a definite range of composition(mole fraction): 70%～75% Mo, 22%～25% w; there appears segregation on the surface of the w Mo alloy source.

关键词： metallic cementation w Mo alloy preferential sputtering ion bombardment

Microstructural evolution of(TiAl)+Nb+w+B alloy

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Transactions of Nonferrous Metals Society of China 2011年第10期21卷 2192-2198页

作者：黄岚 P.K.LIAw C.T.LIU 刘咏黄劲松 Department of Materials Science and Engineering The University of Tennessee 香港城市大学机械与生物医学工程系中南大学粉末冶金研究院长沙410083

A newly designed TiAl alloy containing w,Nb,and B was produced through magnetic-flotation-melting *** production of this TiAl-based alloy,15 kg ingot size,which is quite different from the 0.05 kg small ingot produced by arc-melting,has a large effect on the metallurgical properties,such as the grain size and the phase structures of the *** treatments were carefully designed in order to reduce the amount of the high-temperature remaining β phase in the alloy,and to obtain optimal microstructures for mechanical behavior studies.A room-temperature ductility of 1.9% was obtained in the cast TiAl-based alloy after the appropriate heat *** mechanical behavior of the large ingot through mass production of the TiAl-based alloy was largely improved by the alloy design and subsequent heat treatments.

关键词： TiAl intermetallics w B tensile ductility microstructural evolution large ingot

30-w supercontinuum generation based on ZBLAN fiber in an all-fiber configuration

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Photonics Research 2019年第9期7卷 1061-1065页

作者： LINYONG YANG YING LI BIN ZHANG TIANYI wU YIJUN ZHAO JING HOU College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha410073China Center for Teaching and Research Service National University of Defense TechnologyChangsha410073China State Key Laboratory of Pulsed Power Laser Technology Changsha410073China Hunan Provincial Key Laboratory of High Energy Laser Technology Changsha410073China

we report an all-fiberized 30-w supercontinuum(SC) generation in a piece of ZrF4-BaF2-LaF3-AlF3-NaF(ZBLAN) fiber. The pump source is a thulium-doped fiber amplifier(TDFA) with broadband output spectrum spanning the 1.9 to 2.6 μm region. The used ZBLAN fiber has a core diameter of 10 μm, and was directly fusion-spliced to the pigtail of the TDFA without using a traditional mode field adapter(MFA) or a piece of transition fiber. Such a low-loss and robust fusion splice joint, together with a robust AlF3-fiber-based endcap,enables efficient and high-power SC generation in the ZBLAN fiber. An SC with an average power up to 30.0 w and a spectral coverage of 1.9–3.35 μm with 20-dB bandwidth of 1.92–3.20 μm was obtained. Moreover, an SC with a broader spectrum was achieved by raising the pump pulse peak power(via reducing the duty ratio of the pump laser pulse). An SC with an output power of 27.4 w and a spectral coverage of 1.9–3.63 μm(with 20-dB bandwidth of 1.92–3.47 μm) was obtained, as well as an SC with output power of 24.8 w and a spectral coverage of 1.9–3.70 μm(with 20-dB bandwidth of 1.93–3.56 μm). The power conversion efficiency was measured as>69%. To the best of the authors’ knowledge, this research demonstrates the record output power of SC lasers based on ZBLAN fibers, paving the way for broadband and efficient multi-tens-of-watts SC generation in softglass fibers.

关键词： TDF MFA w supercontinuum generation based on ZBLAN fiber in an all-fiber configuration