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91.
92.
Dehydration kinetics of salmon and trout fillets using ultrasonic vacuum drying as a novel technique
In this study, a novel ultrasonic vacuum (USV) drying technique was used to shorten the drying time of fish fillets. For this purpose, ultrasonic treatment and vacuum-drying were simultaneously performed to dehydrate salmon and trout fillets at 55 °C, 65 °C, and 75 °C. In addition, the USV technique was compared with vacuum-drying and oven-drying techniques. The dehydration kinetics of the fillets was successfully described by seven thin-layer drying models with R2 range between 0.944 and 1.000. Depending on drying temperatures and fish species, the drying times could be shortened using the USV technique between 7.4% and 27.4% compared with vacuum-drying. The highest effective moisture diffusivity was determined in the fillets dried with the USV technique and they increased with increasing drying temperatures. Ultrasonic treatment accelerated the vacuum drying process for the fillets; therefore, this technique could be used to improve the efficiency of vacuum-drying for the fillets. 相似文献
93.
基于微波水热法和微乳液法合成SnO2/TiO2纳米管复合光催化剂.通过X射线衍射(XRD)、配有能量色散X射线光谱仪(EDX)的透射电镜(TEM)和电化学手段对光催化剂进行表征.以甲苯为模型污染物,考察光催化剂在紫外光(UV)和真空远紫外光(VUV)下的性能及失活再生.结果表明,SnO2/TiO2纳米管复合光催化剂形成三元异质结(锐钛矿相TiO2(A-TiO2)/金红石相TiO2(R-TiO2)、A-TiO2/SnO2和R-TiO2/SnO2异质结),促使光生电子-空穴对的有效分离,提高光催化活性.SnO2/TiO2表现出最佳的光催化性能,UV和VUV条件下的甲苯降解率均达100%,CO2生成速率(k2)均为P25的3倍左右.但由于UV光照矿化能力不足,中间产物易在催化剂表面累积.随着UV光照时间的增加,SnO2/TiO2逐渐失活,20 h后k2由138.5 mg·m-3·h-1下降到76.1 mg·m-3·h-1.利用VUV再生失活的SnO2/TiO2,过程中产生的·OH、O2-·、O(1D)、O(3P)、O3等活性物质可氧化吸附于催化剂活性位的难降解中间产物,使催化剂得以再生,12 h后k2恢复到143.6 mg·m-3·h-1.UV和VUV的协同效应使UV降解耦合VUV再生成为一种可持续的光催化降解污染物模式. 相似文献
94.
建立了测定白酒中6种邻苯二甲酸酯类增塑剂的真空离心浓缩/气相色谱-质谱联用(GC-MS)分析方法。样品经真空离心浓缩,正己烷提取,取上层正己烷,4000r/min离心5min,采用GC-MS测定,外标法定量。在0.10~5.00μg/mL范围内,相关系数r20.992,样品在0.10~2.00 mg/kg范围内加标,平均回收率在88.83%~111.67%之间,相对标准偏差(RSD)为4.85%~11.35%,检出限(LOD)在0.02~0.05 mg/kg之间。采用该方法对16个白酒样品进行测定,结果表明该法简便、快速、结果准确可靠、灵敏度高,能够满足白酒中6种邻苯二甲酸酯增塑剂检测需求。 相似文献
95.
In this study, thermal and mechanical properties of novel nanocomposite, epoxy resin reinforced with octadecylamine functionalized graphene oxide (GO-ODA) and Sasobit, prepared via creative vacuum shock technique, were investigated. By introducing 1, 3 and 5 wt% Sasobit to the neat epoxy resin, the tensile strength increased remarkably by 104%, 315% and 266%, respectively due to the unique stiff and crystalline structure of Sasobit. In addition, considerable enhancement of 125% in Young's modulus, 351% in toughness, 562% in impact resistance, ~19 °C in thermal stability and ~7 °C in glass transition temperature of epoxy resin with 3 wt% Sasobit loading was demonstrated. The composite containing 3 wt% Sasobit alone, were found to have even superior properties than GO-ODA/epoxy nanocomposite, as surprisingly 3, 2.9, 2.2 and 2 times more improvement, respectively in tensile strength, toughness, impact strength and thermal stability of epoxy resin compared to reinforcement with GO-ODA were obtained. 相似文献
96.
Felix Burkhardt Carl G. Schirmeister Christian Wesemann Massimo Nutini Stefano Pieralli Erik H. Licht Marc Metzger Frederik Wenz Rolf Mülhaupt Benedikt C. Spies 《Molecules (Basel, Switzerland)》2020,25(24)
A polyolefin with certified biocompatibility according to USP class VI was used by our group as feedstock for filament-based 3D printing to meet the highest medical standards in order to print personal protective equipment for our university hospital during the ongoing pandemic. Besides the chemical resistance and durability, as well as the ability to withstand steam sterilization, this polypropylene (PP) copolymer is characterized by its high purity, as achieved by highly efficient and selective catalytic polymerization. As the PP copolymer is suited to be printed with all common printers in fused filament fabrication (FFF), it offers an eco-friendly cost–benefit ratio, even for large-scale production. In addition, a digital workflow was established focusing on common desktop FFF printers in the medical sector. It comprises the simulation-based optimization of personalized print objects, considering the inherent material properties such as warping tendency, through to validation of the process chain by 3D scanning, sterilization, and biocompatibility analysis of the printed part. This combination of digital data processing and 3D printing with a sustainable and medically certified material showed great promise in establishing decentralized additive manufacturing in everyday hospital life to meet peaks in demand, supply bottlenecks, and enhanced personalized patient treatment. 相似文献
97.
98.
本文从认证方式,测试标准,测试项目,测试限值,符合性标签的使用等方面叙述了美国、加拿大、欧盟、澳洲和新西兰对信息技术设备的EMC要求. 相似文献
100.
本文主要介绍了YY0505—2005《医用电气设备第1-2部分:安全通用要求-并列标准:电磁兼容-要求和试验方法》中医用电气设备的电磁抗扰度测试要求。 相似文献