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Efficacy of Yiqi Fumai (Freeze-Dried Powder) on Ischemic Diastolic Heart Failure 被引量:1
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作者 Dalin Song Mengfen Hu +3 位作者 Tongliang Han Hua Zhang Yongjun Mao Tao Tian 《Chinese Medicine》 2014年第2期75-86,共12页
Objective: To evaluate the efficacy of Yiqi Fumai freeze-dry powder (YFP) on ischemic diastolic heart failure. Methods: 100 patients diagnosed with unstable angina accompanying ischemic diastolic heart failure (IDHF) ... Objective: To evaluate the efficacy of Yiqi Fumai freeze-dry powder (YFP) on ischemic diastolic heart failure. Methods: 100 patients diagnosed with unstable angina accompanying ischemic diastolic heart failure (IDHF) were selected randomly. 52 patients with TCM syndrome of qi-yin deficiency were divided into Chinese and Western combination therapy group. 48 patients have no TCM syndrome of qi-yin deficiency, and were treated with standard western medicine. After treatment, Seattle Angina Questionnaire Evaluation, ECG, conventional and stress echocardiography (SE) index, NT-proBNP were compared between before and after treatment. Results: The differences of PL, TS, DP between before and after treatment by YFP were statistically significant 展开更多
关键词 Yiqi Fumai (freeze-dried powder) DIASTOLIC Heart Failure Seattle ANGINA QUESTIONNAIRE (SAQ) Evaluation Stress ECHOCARDIOGRAPHY
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Component Analysis of Shuanghuanglian Freeze-dried Powder and Its Effects on Human Hepatocyte Function when Combined with Cefradine
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作者 Junlong YU Dazhi XU +1 位作者 Ruyan WEN Xiangling LI 《Medicinal Plant》 CAS 2022年第6期44-48,共5页
[Objectives]To detect the contents of components in Shuanghuanglian freeze-dried powder and to explore the effects of Shuanghuanglian freeze-dried powder and its components on human hepatocytes(HL-7702)alone or in com... [Objectives]To detect the contents of components in Shuanghuanglian freeze-dried powder and to explore the effects of Shuanghuanglian freeze-dried powder and its components on human hepatocytes(HL-7702)alone or in combination with cefradine.[Methods]High performance liquid chromatography(HPLC)was used to detect the contents of baicalin,wogonin,chlorogenic acid and forsythin,the main components of Shuanghuanglian freeze-dried powder.HL-7702 cells were cultured with Shuanghuanglian freeze-dried powder and the main components of Shuanghuanglian freeze-dried powder alone or in combination with cefradine.Enzyme linked immunosorbent assay(ELISA)was used to detect the contents of alanine aminotransferase(ALT)and aspartate aminotransferase(AST)in the cell supernatant after culture,and HPLC was used to detect the expression level of adenosine diphosphate(ADP)and adenosine triphosphate(ATP);agarose gel electrophoresis was used to detect the expression of cyclooxygenase 2(COX-2)and heme oxygenase-1(HO-1)in HL-7702 cells.[Results]In Shuanghuanglian freeze-dried powder for injection,the content of baicalin was the highest,and the content of wogonin was the lowest.Compared with the control group,the expressions of AST and ALT in human hepatocytes(HL-7702)in high-dose baicalin group,forsythin group and wogonin group decreased(P<0.05,P<0.01),while the expression of ALT in chlorogenic acid+cefradine group(0.046 mg/mL)and forsythin+cefradine group(0.046 mg/mL)increased(P<0.05,P<0.01),and the expression of AST had no significant difference(P>0.05);the results in the low-dose group were similar to those in the high-dose group.Compared with the control group,ATP expression in chlorogenic acid group,chlorogenic acid+cefradine group(0.046 mg/mL)and forsythin+cefradine group(0.046 mg/mL)in the high-dose group decreased(P<0.05,P<0.01),and ADP expression was not significantly different(P>0.05);in the low-dose group,the expression of ATP and ADP increased in baicalin group(P<0.05),but decreased in wogonin group,baicalin+cefradine group(0.046 mg/mL)and wogonin group+cefradine group(0.046 mg/mL)(P<0.05,P<0.01).Compared with the control group,the expressions of COX-2 and HO-1 in HL-7702 cells in the cefradine group showed no significant difference(P>0.05).The expression of HO-1 and COX-2 in the different dose groups of Shuanghuanglian and the group combined with cefradine increased,and the difference was significant(P<0.05,P<0.01).[Conclusions]The components of Shuanghuanglian freeze-dried powder for injection had effects on hepatocytes,of which baicalin had a significant effect,and the effect of cefradine on hepatocytes was increased when used in combination with cefradine. 展开更多
关键词 Shuanghuanglian freeze-dried powder CEFRADINE HL-7702 Alanine aminotransferase Aspartate aminotransferase Adenosine diphosphate Adenosine triphosphate Cyclooxygenase 2 Heme oxygenase-1
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Technological Study on Instant Date Powder in Natural Ziziphus jujuba through Vacuum Freeze-drying 被引量:1
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作者 ZHANG Jun-he GAO Hai-yan SHI Rui Henan 《Agricultural Science & Technology》 CAS 2010年第7期69-71,175,共4页
[Objective] The aim was to get optimized conditions for date powder with good color and taste.[Method] The pectinase enzymolysis and vacuum freeze-drying technology were used in the extract process of date powder.[Res... [Objective] The aim was to get optimized conditions for date powder with good color and taste.[Method] The pectinase enzymolysis and vacuum freeze-drying technology were used in the extract process of date powder.[Result] The production boasts of superior quality were with rich fragrance and uniform particle under certain process conditions.The optimized conditions for pectinase enzymolysis were:the amount of pectinase reached to 0.1% of that of date syrup,enzymolysis temperature and time were 50 ℃ and 50 min respectively,the pH value was 4.0.The optimized conditions for vaccum freeze-drying were:10% altodextrin,three times volumn of water with the thickness of 7 mm.[Conclusion] The optimized conditions were obtained in this study to produce instant date powder from Ziziphus jujuba. 展开更多
关键词 真空冷冻干燥技术 金丝小枣 即时 最佳工艺条件 天然 粉末 酶解温度 最佳条件
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Various Temperature of Vacuum and Conventional Roasting on Color Alteration and Polyphenols Content of Cocoa Powder
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作者 Tamrin narijono +2 位作者 Sudarminto Setvo Yuwono: Teti Estiasih Umar Santoso 《Journal of Food Science and Engineering》 2012年第11期642-651,共10页
关键词 茶多酚含量 焙烧温度 焙烧时间 真空烘烤 颜色变化 可可粉 酚类物质含量 烘烤系统
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导流管参数对真空紧耦合气雾化法制备Fe-Cr合金粉末的影响 被引量:1
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作者 苏才津 孙耀宁 +3 位作者 董开基 尹燕 张瑞华 姜立恒 《粉末冶金技术》 CAS CSCD 北大核心 2024年第1期68-74,共7页
采用真空紧耦合气雾化法制备Fe–Cr合金粉末,研究了导流管直径与导流管伸出长度对Fe–Cr合金粉末粒度分布、收得率、中位粒径(D_(50))的影响。结果表明,在其他工艺参数不变的情况下,当导流管直径从4.5 mm增大到6.0 mm时,Fe–Cr合金粉末... 采用真空紧耦合气雾化法制备Fe–Cr合金粉末,研究了导流管直径与导流管伸出长度对Fe–Cr合金粉末粒度分布、收得率、中位粒径(D_(50))的影响。结果表明,在其他工艺参数不变的情况下,当导流管直径从4.5 mm增大到6.0 mm时,Fe–Cr合金粉末累积粒度分布曲线右移,中位粒径增大,细粉收得率减小,粉末流动性减小,松装密度减小;当导流管伸出长度由2.0 mm增加到2.5 mm时,Fe–Cr合金粉末累积粒度分布曲线左移,中位粒径减小,细粉收得率增加,粉末流动性增加,松装密度升高。综上所述,雾化压力3.8 MPa,过热度250℃,导流管直径4.5 mm,导流管伸出长度2.5 mm,制备得到的Fe–Cr合金粉末综合性能最优。 展开更多
关键词 真空紧耦合气雾化法 Fe–Cr金属粉末 导流管 粉末性能
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干燥方式对毛竹笋全粉理化特性及结构的影响
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作者 李艳艳 史早 +4 位作者 冉莎 杨金来 李彬 吴良如 郑炯 《食品工业科技》 CAS 北大核心 2024年第14期89-96,共8页
为探究干燥方式对毛竹笋全粉(Phyllostachys pubescens shoot powder,PPSP)理化特性及结构的影响,该实验以毛竹笋为原料,采用喷雾干燥(Spray drying,SD)、热风干燥(Hot air drying,HAD)和低温真空干燥(Low-temperature vacuum drying,LV... 为探究干燥方式对毛竹笋全粉(Phyllostachys pubescens shoot powder,PPSP)理化特性及结构的影响,该实验以毛竹笋为原料,采用喷雾干燥(Spray drying,SD)、热风干燥(Hot air drying,HAD)和低温真空干燥(Low-temperature vacuum drying,LVD)3种方式制备PPSP,比较3种PPSP的营养成分、持水力、持油力、膨胀力、色泽等理化特性,并通过红外光谱、X-射线衍射、扫描电镜分析其结构。结果表明,不同干燥方式制备的PPSP营养成分差异显著(P<0.05),LVD组的蛋白质、不溶性膳食纤维、灰分、总糖含量均显著高于其他2组(P<0.05),而水分、可溶性膳食纤维含量最低;HAD组中可溶性膳食纤维含量最高,达5.79%;HAD组样品的持水力和持油力分别为4.10、1.91 g/g,显著高于SD组和LVD组(P<0.05);SD样品的膨胀力最高,达到3.85 mL/g;3组PPSP的滑角和休止角差异显著(P<0.05),其中,SD>LVD>HAD;3组PPSP的L*值、a*值、b*值均有显著差异(P<0.05),LVD样品的L*值为77.32,显著高于SD和HAD样品(P<0.05),且其a*值和b*值最低,分别为3.74、14.50;SD和LVD显著降低了样品的热稳定性(P<0.05)。干燥方式未改变PPSP的基本结构和官能团以及晶体结构。扫描电镜观察到SD制备的PPSP颗粒尺寸明显减小,分布更为均匀。综上所述,LVD制备的毛竹笋干制品营养、理化特性及结构整体最佳,其次是SD。研究结果可为高品质PPSP的制备提供理论参考。 展开更多
关键词 毛竹笋全粉 喷雾干燥 热风干燥 低温真空干燥 理化特性
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亚微米球形Y_(2)O_(3)粉体及其透明陶瓷的制备
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作者 刘焱 覃显鹏 +4 位作者 甘霖 周国红 章天金 王士维 陈鹤拓 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2024年第6期691-696,共6页
Y_(2)O_(3)以其优良的物理化学性质和在280 nm~8μm宽频段内的高透明性,而广泛应用于激光介质或光学窗口等领域。制备高透明的Y_(2)O_(3)陶瓷是目前的研究热点和难点,而高质量的粉体是制备高透明Y_(2)O_(3)陶瓷的关键,尿素均相沉淀法以... Y_(2)O_(3)以其优良的物理化学性质和在280 nm~8μm宽频段内的高透明性,而广泛应用于激光介质或光学窗口等领域。制备高透明的Y_(2)O_(3)陶瓷是目前的研究热点和难点,而高质量的粉体是制备高透明Y_(2)O_(3)陶瓷的关键,尿素均相沉淀法以其爆发成核和均匀可控的阴离子释放机制成为制备单分散颗粒的主要方法。本工作以硝酸钇和尿素为原料,采用尿素均相沉淀法制备了单分散、亚微米级的球形Y_(2)O_(3)粉体。采用不同方法研究了Y_(2)O_(3)前驱体和煅烧后粉体的结构、物相演变和形貌。前驱体的颗粒尺寸约为330 nm,800℃煅烧2 h得到的Y_(2)O_(3)粉体尺寸约为260 nm。在800℃煅烧后即可得到纯相的Y_(2)O_(3)粉体,粉体呈球形,分散性好,且粒径均匀。以该Y_(2)O_(3)粉体为原料,添加原子分数0.3%的Nb_(2)O_(5)为烧结助剂,在1780℃通过真空无压烧结成功制备了透明Y_(2)O_(3)陶瓷。材料的光学性质优良,即样品(厚度1 mm)的直线透过率在1100 nm处达到76.9%,在400 nm处达到65.6%。本工作为制备性能优良的Y_(2)O_(3)透明陶瓷提供了一种新的方法。 展开更多
关键词 尿素均相沉淀法 亚微米球形Y_(2)O_(3)粉体 透明Y_(2)O_(3)陶瓷 Nb_(2)O_(5) 真空烧结
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真空气雾化法制备AlSi10Mg粉末参数优化及打印态组织性能研究
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作者 蒋保林 蒋崴 +5 位作者 许荣玉 陈烜 吕复强 赵永柱 付珂 陈正 《精密成形工程》 北大核心 2024年第2期96-103,共8页
目的探究利用真空气雾化法制备AlSi10Mg球形粉末过程中各参数对粉末质量的影响,以得到最佳的制粉工艺参数。以制备的粉末进行增材制造,研究块体组织及其力学性能。方法针对制备的球形粉末,采用扫描电镜(SEM)观察粉末的球形度及其内部组... 目的探究利用真空气雾化法制备AlSi10Mg球形粉末过程中各参数对粉末质量的影响,以得到最佳的制粉工艺参数。以制备的粉末进行增材制造,研究块体组织及其力学性能。方法针对制备的球形粉末,采用扫描电镜(SEM)观察粉末的球形度及其内部组织。通过分析球形粉末的平均粒径与粒度分布区间总结最优制粉参数。针对以球形粉末增材制造出的沉积态样品,采用X射线衍射仪(XRD)、扫描电镜(SEM)研究其微观组织形貌并通过拉伸试验研究其力学性能。结果真空气雾化法制备出的粉末表面光洁且球形度良好,同时粉末平均粒径随雾化压力的增大呈现先减小后增大的趋势并在4.0 MPa时粒径最小,且与环孔喷嘴相比,环缝喷嘴制备出的粉末粒径更小。粉末内部组织由胞状晶与树枝晶构成。通过SLM制备的沉积态样品组织以沿沉积方向的枝晶为主,该样品的力学性能较优异,断裂方式主要为沿晶断裂。结论在使用真空气雾化法制备增材制造用球形粉末时,应选择4.0 MPa的气雾化压力并选择环缝喷嘴,方能得到质量最佳的球形粉末。 展开更多
关键词 增材制造 球形粉末 真空气雾化法 工艺参数 AlSi10Mg合金
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m(ZnO)/m(B_(2)O_(3))质量比对低熔点封接玻璃Bi_(2)O_(3)-B_(2)O_(3)-ZnO结构、性能与润湿性的影响
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作者 康涛 熊春荣 +4 位作者 符有杰 蔡邦辉 魏曙光 李军葛 姜宏 《硅酸盐通报》 CAS 北大核心 2024年第4期1341-1349,共9页
针对真空玻璃封接的性能要求,本文采用高温熔融法制备了一种针对真空玻璃封接的铋系非晶无铅玻璃粉,通过高温X射线衍射、粉末X射线衍射、拉曼光谱、差式扫描量热仪、热膨胀测试和扫描电子显微镜等测试方法,研究了m(ZnO)/m(B_(2)O_(3))... 针对真空玻璃封接的性能要求,本文采用高温熔融法制备了一种针对真空玻璃封接的铋系非晶无铅玻璃粉,通过高温X射线衍射、粉末X射线衍射、拉曼光谱、差式扫描量热仪、热膨胀测试和扫描电子显微镜等测试方法,研究了m(ZnO)/m(B_(2)O_(3))质量比对Bi_(2)O_(3)-B_(2)O_(3)-ZnO玻璃的网络结构、特征温度、热膨胀系数和封接温度的影响。结果表明,增加m(ZnO)/m(B_(2)O_(3))质量比可促进锌氧多面体由[ZnO_(4)]向[ZnO_(6)]转变,导致热膨胀系数降低,特征温度升高。当m(Bi_(2)O_(3))∶m(B_(2)O_(3))∶m(ZnO)质量比为80∶7∶13,玻璃具有较低的玻璃化转变温度T_(g)(371℃)和膨胀软化温度T_(f)(401℃),热膨胀系数为9.3×10^(-6)℃^(-1),封接温度为450℃,可满足真空玻璃封接对低熔点封接玻璃粉的要求。 展开更多
关键词 m(ZnO)/m(B_(2)O_(3))质量比 特征温度 Bi_(2)O_(3)-B_(2)O_(3)-ZnO玻璃 真空玻璃 封接温度 封接玻璃粉
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火龙果粉冷冻-真空微波干燥工艺优化及贮藏品质
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作者 靳学远 黄丽萍 张培旗 《食品研究与开发》 CAS 2024年第6期136-141,166,共7页
为优化火龙果粉的冷冻干燥结合真空微波干燥工艺并研究其贮藏品质,以火龙果为原料,以复水比和维生素C保留率加权转化的综合评分为指标,通过单因素和响应面试验优化火龙果粉的工艺条件并分析其贮藏品质。结果表明,优化后的工艺条件为采... 为优化火龙果粉的冷冻干燥结合真空微波干燥工艺并研究其贮藏品质,以火龙果为原料,以复水比和维生素C保留率加权转化的综合评分为指标,通过单因素和响应面试验优化火龙果粉的工艺条件并分析其贮藏品质。结果表明,优化后的工艺条件为采用冷冻干燥将火龙果干燥到水分含量35%后,再采用真空度40 Pa、微波功率1 500 W的真空微波干燥继续将其干燥至水分含量3.5%。该条件下,产品实际综合评分为85.17,与理论预测值基本吻合。联合干燥技术的产品在25℃、相对湿度65%的条件下贮藏30 d时,火龙果粉中的VC保留率为(83.36±0.65)%,感官评分65.6,VC的保留率和感官评分均较高,具有较好的贮藏品质。 展开更多
关键词 火龙果粉 冷冻干燥 真空微波干燥 工艺 贮藏特性
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铸造/烧结钴铬镍合金组织演变规律的对比研究
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作者 李光宇 石增敏 +4 位作者 邓李辰贵 王珂胜 朱哲 戴雷 赵光伟 《材料工程》 EI CAS CSCD 北大核心 2024年第5期127-137,共11页
采用亚快速凝固和真空烧结两种工艺方法制备了钴铬镍合金,详细研究了工艺方法及Cr,Ni含量对合金组织演变规律的影响。结果表明,亚快速凝固工艺所获得的钴铬镍合金组织组成不受成分变化的影响,凝固组织为γ-fcc+ε-hcp两相组织的胞状枝晶... 采用亚快速凝固和真空烧结两种工艺方法制备了钴铬镍合金,详细研究了工艺方法及Cr,Ni含量对合金组织演变规律的影响。结果表明,亚快速凝固工艺所获得的钴铬镍合金组织组成不受成分变化的影响,凝固组织为γ-fcc+ε-hcp两相组织的胞状枝晶,枝晶干为γ-fcc相,枝晶间为ε-hcp相,二次枝晶间距随结晶速率增大而减小,主要溶质元素Cr,Ni在两相间产生偏析,Cr元素富集在枝晶间,Ni元素在枝晶干富集。真空烧结工艺所制备钴铬镍合金组织构成由成分组成决定,低镍含量合金烧结体为单相ε-hcp组织,晶粒随烧结温度的升高呈现急剧粗化特征;高镍含量合金烧结体为γ-fcc+ε-hcp双相组织,晶粒细小且γ-fcc相呈现明显的孪晶和层错结构。烧结合金较铸造合金呈现明显的塑性增长,位错是烧结低镍ε-hcp单相合金性能提升的主要因素,孪晶和层错则是高镍γ-fcc+ε-hcp两相合金组织性能提升的主要因素。 展开更多
关键词 钴铬镍合金 粉末冶金 真空烧结 亚快速凝固 组织演变
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气体温度对VIGA制备GH4169合金粉末的影响
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作者 蒋保林 魏放 +1 位作者 陆雪雯 丁西安 《现代制造技术与装备》 2024年第5期148-151,共4页
研究采用真空感应气雾化(Vacuum Induction Gas Atomization,VIGA)技术制备GH4169合金粉末,系统探究气体温度对粉末特性的影响规律。结果表明,随着气体温度从100℃升高到600℃,粉末的粒度分布明显向左移动,D50由75μm减小到42μm。扫描... 研究采用真空感应气雾化(Vacuum Induction Gas Atomization,VIGA)技术制备GH4169合金粉末,系统探究气体温度对粉末特性的影响规律。结果表明,随着气体温度从100℃升高到600℃,粉末的粒度分布明显向左移动,D50由75μm减小到42μm。扫描电子显微镜(Scanning Electron Microscope,SEM)分析表明,较高气体温度有助于提高粉末的球形度,减少卫星粉的生成。X射线衍射(X-Ray Diffraction,XRD)分析揭示,气体温度对粉末的物相组成影响不大,但是较高温度下粉末具有更高的结晶度和更大的晶粒尺寸。此外,粉末的流动性随气体温度的升高而显著改善。 展开更多
关键词 真空感应气雾化 GH4169合金粉末 真空感应气雾化(VIGA)技术 气体温度 粒度分布
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紫薯复合营养餐粉的研制及冲调性能研究
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作者 韩晓宇 黄利华 +1 位作者 吕佳豪 胡荣柳 《江苏调味副食品》 2024年第2期18-23,共6页
以采用真空冷冻干燥技术制备的紫薯全粉为主要原料,添加燕麦粉、魔芋粉、脱脂奶粉及木糖醇等制备紫薯复合营养餐粉。紫薯复合营养餐粉的最佳配方为紫薯粉2.8 g(26.4%)、魔芋粉0.6 g(5.7%)、燕麦粉2.8 g(26.4%)、脱脂奶粉2.4 g(22.6%)、... 以采用真空冷冻干燥技术制备的紫薯全粉为主要原料,添加燕麦粉、魔芋粉、脱脂奶粉及木糖醇等制备紫薯复合营养餐粉。紫薯复合营养餐粉的最佳配方为紫薯粉2.8 g(26.4%)、魔芋粉0.6 g(5.7%)、燕麦粉2.8 g(26.4%)、脱脂奶粉2.4 g(22.6%)、木糖醇2.0 g(18.9%)。紫薯复合营养餐粉的最佳冲调温度为75℃,最佳冲调水量(营养餐粉质量/冲调用水量)为1∶8,结块率为0.53%,润湿下沉性及速溶性较好。 展开更多
关键词 紫薯营养餐粉 真空冷冻干燥技术 冲调性能
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Physical Modeling of the Vacuum Circulation Refining Process of Molten Steel 被引量:5
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作者 魏季和 《Journal of Shanghai University(English Edition)》 CAS 2003年第1期1-17,共17页
The available studies in the literature on physical modeling of the vacuum circulation (RH, i.e. Ruhrstahl Heraeus) refining process of molten steel have briefly been reviewed. The latest advances made by the author ... The available studies in the literature on physical modeling of the vacuum circulation (RH, i.e. Ruhrstahl Heraeus) refining process of molten steel have briefly been reviewed. The latest advances made by the author with his research group have been summarized. Water modeling was employed to investigate the flow and mixing characteristics of molten steel under the RH and RH KTB (Kawasaki top blowing) conditions and the mass transfer features between molten steel and powder particles in the RH PTB (powder top blowing) refining. The geometric similarity ratio between the model and its prototype (a multifunction RH degasser of 90 t capacity) was 1:5. The effects of the related technological and structural factors were considered. These latest studies have revealed the flow and mixing characteristics of molten steel and the mass transfer features between molten steel and powder particles in these processes, and have provided a better understanding of the refining processes of molten steel. 展开更多
关键词 vacuum circulation refining RH process RH KTB (Kawasaki top blowing) process RH PTB (powder top blowing) process flow mixing mass transfer characteristics between molten steel and particles water modeling
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Mathematical Modeling of the Vacuum Circulation Refining Process of Molten Steel 被引量:1
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作者 魏季和 《Journal of Shanghai University(English Edition)》 CAS 2003年第2期97-117,共21页
The available studies in the literature on mathematical modeling of the vacuum circulation (RH) refining process of molten steel have briefly been reviewed. The latest advances obtained by the author with his research... The available studies in the literature on mathematical modeling of the vacuum circulation (RH) refining process of molten steel have briefly been reviewed. The latest advances obtained by the author with his research group have been summarized. On the basis of the mass and momentum balances in the system, a new mathematical model for decarburization and degassing during the RH and RH KTB refining processes of molten steel was proposed and developed. The refining roles of the three reaction sites, i.e. the up snorkel zone, the droplet group and steel bath in the vacuum vessel, were considered in the model. It was assumed that the mass transfer of reactive components in the molten steel is the rate control step of the refining reactions. And the friction losses and drags of flows in the snorkels and vacuum vessel were all counted. The model was applied to the refining of molten steel in a multifunction RH degasser of 90 t capacity. The decarburization and degassing processes in the degasser under the RH and RH KTB operating conditions were modeled and analyzed using this model. Besides, proceeded from the two resistance mass transfer theory and the mass balance of sulphur in the system, a kinetic model for the desulphurization by powder injection and blowing in the RH refining of molten steel was developed. Modeling and predictions of the process of injecting and blowing the lime based powder flux under assumed operating modes with the different initial contents of sulphur and amounts of powder injected and blown in a RH degasser of 300 t capacity were carried out using the model. It was demonstrated that for the RH and RH KTB refining processes, and the desulphurization by powder injection and blowing in the RH refining, the results predicted by the models were all in good agreement respectively with data from industrial experiments and practice. These models may be expected to offer some useful information and a reliable basis for determining and optimizing the technologies of the RH and RH KTB refining and desulphurization by powder injection and blowing in the RH refining and for controlling the processes. 展开更多
关键词 vacuum circulation refining RH process RH KTB (Kawasaki top blowing) process RH PTB (powder top blowing) process decarburization degassing desulphurization by powder injection and blowing mathematical modeling
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Preparation of Garlic Powder with High Allicin Content 被引量:3
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作者 LI Yu XU Shi-ying 《Agricultural Sciences in China》 CAS CSCD 2007年第7期890-898,共9页
Garlic powder with high allicin content was prepared using microwave-vacuum and vacuum drying as well as microencapsulation to protect alliinase activity throughout the stomach and improve the ratio of alliin transfor... Garlic powder with high allicin content was prepared using microwave-vacuum and vacuum drying as well as microencapsulation to protect alliinase activity throughout the stomach and improve the ratio of alliin transforming into allicin. The results showed that the optimal drying condition was 376.1 W for 3 min, 282.1 W for 3 min, 188 W for 9 min, and 94 W for 3 min. The thiosulfinates retention after drying was 90.2%. Following drying, the garlic powder was microencapsulated by modified fluidized bed technique. Scanning electron microscope revealed good integrity and core materials that were embedded in the microcapsules. Studies on the release kinetics of microencapsulated garlic granulates in vitro using simulated intestinal fluid indicated that release of garlic powder could be controlled in the intestine by passing stomach conditions. 展开更多
关键词 ALLICIN thiosulfinates microwave-vacuum drying garlic powder MICROENCAPSULATION
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ON ZrO_2-NiCr COMPOSITE POWDER FOR SPRAYING
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作者 邱凤襄 罗志平 +1 位作者 邵刚勤 潘牧 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1995年第4期42-47,共6页
Composite powder prepared of calcium oxide stabilzed ZrO2(CSZ) and NiCr by vacuum sintering is studied,and the effect of additive TiO2 on its properties is discussed. The morphology and phases of the powder were measu... Composite powder prepared of calcium oxide stabilzed ZrO2(CSZ) and NiCr by vacuum sintering is studied,and the effect of additive TiO2 on its properties is discussed. The morphology and phases of the powder were measured and determined by SEM. EPMA, XRD methods and the testing of flowability, bulk density and microhard-ness. The results show that the metallic components in the powder are in homogeneous distribution , the flowability, bulk density and microhardness are superior to the ZrO2-NiCr powder prepared by mechanically mixing. All components in the coating made of the composite powder are well-distributed because of avoiding segregation in the middle of mixing. It proves that the composite powder is an excellent material for plasma spraying. 展开更多
关键词 composite powder ZRO2 vacuum sin-tering plasma spraying
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Interface microstructure and diffusion of vacuum annealed ceramic coating on superalloy GH202
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作者 古一 夏长清 +1 位作者 邱冠周 王志法 《中国有色金属学会会刊:英文版》 CSCD 2009年第S3期701-705,共5页
In order to improve the wear resistance and high-temperature oxidation resistance of superalloy GH202, the ultrafine-grain ceramic coating containing nano-size nickel particles was obtained by flow coat method on the ... In order to improve the wear resistance and high-temperature oxidation resistance of superalloy GH202, the ultrafine-grain ceramic coating containing nano-size nickel particles was obtained by flow coat method on the surface of GH202. The interface microstructure between ceramic coating and superalloy GH202 substrate during vacuum diffusion was studied. It is shown that Al2O3 oxide layer and (Ti, N) compound exist in the alloy substrate close to interface. During long time diffusion, nano-size nickel powders gradually congregate and grow up, and the confluent interface appears, which shows that the nano-size nickel powders have the effect of restraining the coating from failure. 展开更多
关键词 GH202 SUPERALLOY NANO-SIZE nickel powder ceramic coating vacuum annealing MICROSTRUCTURE
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Room-Temperature Ferromagnetism in Fe/Sn-Codoped In_(2)O_(3)Powders and Thin Films
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作者 江凤仙 席识博 +5 位作者 马荣荣 秦秀芳 樊晓晨 张敏刚 周俊琪 许小红 《Chinese Physics Letters》 SCIE CAS CSCD 2013年第4期181-184,共4页
Fe/Sn-codoped In_(2)O_(3)powders and films are prepared by a vacuum annealing process and a pulsed laser deposition technique,respectively.The structural and magnetic properties of the samples are investigated.The obv... Fe/Sn-codoped In_(2)O_(3)powders and films are prepared by a vacuum annealing process and a pulsed laser deposition technique,respectively.The structural and magnetic properties of the samples are investigated.The obvious room-temperature ferromagnetism is observed in both(In_(0.92)Fe_(0.05)Sn_(0.03))_(2)O_(3)powders and films,but their magnetic behaviors are very different.The ferromagnetism of the vacuum-annealed powders is partially due to precipitated Fe_(3)O_(4)impurity.By contrast,the ferromagnetism of the films is intrinsic and does not originate from any magnetic impurity,as confirmed by the extensive x-ray absorption spectroscopy and magnetization studies. 展开更多
关键词 powderS vacuum FILMS
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真空冷冻干燥猕猴桃粉工艺的研究 被引量:1
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作者 彭润玲 王威 +3 位作者 韦妍 屈安娜 翟浩楠 刘锦悦 《真空》 CAS 2023年第2期20-25,共6页
针对猕猴桃常规干燥保存过程中不易成粉且化学添加剂过多等问题,本文比较了热风干燥、喷雾干燥、冷冻干燥3种干燥方式下猕猴桃粉的品质,并研究了冷冻干燥法制备猕猴桃粉过程中,预冻方式、浆体比例、助干剂种类、猕猴桃新鲜度等因素对猕... 针对猕猴桃常规干燥保存过程中不易成粉且化学添加剂过多等问题,本文比较了热风干燥、喷雾干燥、冷冻干燥3种干燥方式下猕猴桃粉的品质,并研究了冷冻干燥法制备猕猴桃粉过程中,预冻方式、浆体比例、助干剂种类、猕猴桃新鲜度等因素对猕猴桃粉品质的影响。结果表明:相比热风和喷雾干燥,冷冻干燥法制备的猕猴桃粉综合品质较好、速溶性好、产率较高;采用冻干法制备猕猴桃粉的较优工艺为选取九成熟(盛花后约175天)的猕猴桃去皮打浆,以体积比(猕猴桃浆:酸奶)1∶1添加酸奶,铺料厚度4mm,经-20℃预冻后,在真空环境下干燥10h。 展开更多
关键词 冷冻干燥 猕猴桃粉 真空 冻干工艺
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