聚亚胺亚胺酮泡沫制备的计算机模拟及其结构表征

以4,4-二-溴二苯甲酮和对苯二胺为单体,在钯催化体系(BINAP/(Pd2(dba)3)作用下得到聚亚胺亚胺酮(PIIK)(Mn=35000,Mw=125000,Mw/Mn=3.57)。通过Materials Studio(MS,version 4.3Accelrys Software Inc.,SanDiego,CA,USA)中的Blends模块对PIIK/Dioxane溶液体系的热致相分离行为进行了计算模拟。模拟结果显示PIIK/Dioxane体系可实现液-液相分离。在理论模拟的支持下,采用热致相分离和冷冻干燥技术成功制备了不同密度的PIIK泡沫,其密度在80～300mg/cm3之间,平均孔径低于5μm。     

冻干轮叶党参脆片加工工艺

目的：以轮叶党参为原料生产冻干轮叶党参脆片。方法：采用清洗、切分、热烘脱皮、填充等预处理后,经预冻结再进行升华干燥。结果：热烘脱皮以100℃、20min 最佳,升华干燥最佳装料量为9.4kg/m2,加热温度为80-65-45℃,真空室压力25-100Pa。结论：按此工艺得到的冻干轮叶党参脆片产品口感酥脆,香气浓郁,营养丰富。     

Comparison study on strategies to prepare nanocrystalline Li2ZrO3-based absorbents for CO2 capture at high temperatures

A comparison study has been conducted on the strategies for synthesizing nanocrystalline Li₂ZrO₃ and K-doped Li₂ZrO₃ absorbents for CO₂ capture at high temperatures, including solid-state and liquid-phase methods, citrate route, and starch-assisted sol-gel method combined with freeze-drying technique. The absorption properties, including uptake rate and absorption capacity, of synthesized absorbents were investigated by thermogravimetric analysis (TGA) at different CO₂ partial pressures. The nanosized Li₂ZrO₃ crystals synthesized by the citrate route exhibit a faster uptake and a higher, nearly stoichiometric absorption capacity than those synthesized by the solid-state and liquid-phase methods. The doping of K into Li₂ZrO₃ can significantly improve the uptake rate of CO₂, especially at low CO₂ partial pressures. For the synthesis of K-doped Li₂ZrO₃, the citrate route has poor reproducibility and scalability, whereas the starch-assisted sol-gel method combined with freeze-drying technique is reproducible and easily scaled up, and the thus synthesized absorbents possess excellent CO₂ capture properties.     

初始非饱和多孔物料对冷冻干燥过程的影响

提出了“初始非饱和多孔物料冷冻干燥”的思想,从实验上验证具有一定初始孔隙的非饱和多孔物料对液体物料冷冻干燥过程的强化作用。设计、加工和组装了一套实验室规模的多功能冷冻干燥装置。采用“液氮制作冰激凌法”,将以甘露醇为主要溶质的液体物料制备成具有不同初始孔隙的冷冻物料。对于相同质量和相同湿含量的非饱和冷冻物料,在相同的操作条件下,进行冷冻干燥实验,并与常规冷冻干燥相比较。结果表明,初始非饱和物料对冷冻干燥过程确实具有显著的强化作用。非饱和冷冻物料(初始饱和度0.28)的干燥时间比常规冷冻物料(初始饱和度1.00)能够节省36.4%。初始饱和度越小,干燥时间越短,干燥产品的含水率越低。     

冷冻干燥工艺程序自动化研究

对冷冻干燥过程中的传热传质进行分析,依据冻干塌陷原理,编制具有自适应性的逻辑公式,设置物料塌陷温度、真空仓压力和过热度等输入参数.在BSNFD05冻干机上进行测试,结果表明,在冷冻干燥过程中,按照PLC中的自适应逻辑,以高精量传感器采集的加热板温度、真空仓压力和冷阱（捕水器）过热度为控制量,通过三通调节阀、真空挡板阀和供液电子膨胀阀等执行机构,实现在冷冻干燥过程中按照逻辑判断、不断修正自动形成工艺程序,最终完成冷冻干燥.     

真空冷冻干燥超细天麻粉体的研制

真空冷冻干燥(简称冻干FD)是发展近代生物医药工程与中药现代化的关键高新技术,近年来,日本将中国名贵中药天麻制成超细粉体胶囊(粉体中心粒径D50～50μm),用来取代西药治疗失眠,取得很好效果,无毒副作用.据近年研究表明,在中药粉体的中心粒径达到10 μm～15 μm的细度以下时,人体对其有效成份的吸收率将会更好.在此研制的鲜天麻真空冷冻干燥超细粉,按粒子分布曲线(用Mastersizer-2000型激光衍射仪检测)与4000倍扫描电子显微镜检测,其粉体中心粒径高达D50=12.996μm,部分还进入亚微米级.本文对其研制方法、技术、设备及检测质量控制等作了阐述.     

Comparative lyophilized platelet-rich plasma wafer and powder for wound-healing enhancement: formulation,in vitro and in vivo studies

Platelet-rich plasma (PRP) accelerates wound healing, as it is an excellent source of growth factors. PRP was separated from whole human blood by centrifugation. PRP powder and wafers were prepared by lyophilization, with the wafers prepared using sodium carboxymethylcellulose (Na CMC). The PRP wafers showed porous structures, as indicated by scanning electron microscopy (SEM) images, and the ability of the wafer to absorb exudates and thus promote wound healing was tested with the hydration capacity test. The platelet count was tested and indicated that the presence of PRP in the wafers had no effect on the platelet count. An antimicrobial activity test was carried out, showing that PRP had antibacterial activity against Gram-negative bacteria. Compared with lyophilized PRP powder and PRP-free wafers, PRP wafers showed the highest percent of wound size reduction on induced wounds in rats. Histopathological examination of rat skin showed that the PRP wafers achieved the shortest healing time, followed by the lyophilized PRP powder and finally the PRP-free wafers. The present study revealed that PRP can be formulated as a wafer, which is a promising pharmaceutical delivery system that can be used for enhanced wound-healing activity and improved the ease of application compared to lyophilized PRP powder.     

黑加仑真空冷冻与微波真空联合干燥工艺研究

以黑加仑为原料,对其进行了真空冷冻与微波真空联合干燥工艺的研究。结果表明：先真空冷冻后微波真空干燥（FDMV）的组合方式是可行的;联合干燥合理工艺参数为：微波功率1．34kW。绝对压力11kPa,转换含水率为20％（wb）;通过试验验证,联合干燥生产的脱水黑加仑的感官品质和营养成分接近真空冷冻干燥,联合干燥方式对节省干燥时间和降低能耗是有效的。     

奶粉微波真空喷雾冷冻干燥技术与设备研究

主要分析了微波真空冷冻干燥的技术特性,以及在应用中容易出现理论、工艺和设备问题,并提出了相应的技术方法和手段。研究开发了集微波技术、喷雾干燥、冷冻干燥为一体的奶粉干燥装置,实现奶粉在-40～-30℃冷冻干燥。     

鹿茸的冻干新工艺及性质

传统的鹿茸干燥工艺中包含煮炸、烘烤、日晒等加热处理步骤,会造成鹿茸中营养物质的流失及其生物活性的破坏。冷冻真空干燥是能够保持鹿茸中营养成分活性的先进干燥工艺。本文详细介绍了鹿茸片和整枝鹿茸的冷冻真空干燥实验。分别用温度电阻法和DSC法测定鹿茸的共晶点约为-15℃。用卤素水分测量仪测定鹿茸整体平均含水量约为70%。文中给出了一个22 h的鹿茸片的冷冻干燥工艺曲线,描述了整枝鹿茸的冻干工艺。为保持鹿茸生物活性及保留营养物质,在冻干工艺中特别控制物料温度不超过45℃。对比了冻干鹿茸与传统干燥鹿茸的性质,列出了两者的显微观察照片和成分分析数据。