超声波辅助酶法提取骨明胶研究

以脱脂脱矿骨粉为原料,利用超声波辅助胃蛋白酶法提取骨明胶。比较了骨素酶解前、酶解中以及酶解后经不同超声时间和功率处理对明胶得率的影响,单因素实验结果表明:骨素酶解前和酶解中经超声处理,明胶得率显著提高。在骨素酶解前和酶解中分别经250 W、20 min和250 W、10 min的超声处理,明胶的得率分别为81.35%和83.32%,与未经超声处理组相比,明胶得率分别提高了9.96%和11.93%,而骨素酶解后在300 W超声功率下处理10 min,明胶得率仅为71.59%,与未超声处理组71.39%接近。SEM图片显示,酶解前和酶解中经超声处理,会使骨素表面出现孔隙,而酶解后超声处理则会使骨素表面更加光滑,表明酶解前和酶解中超声处理对骨素具有疏松作用。SDS-PAGE结果显示,超声波辅助酶法提取明胶,对明胶分子量分布没有影响。超声波辅助酶法提取,提高了骨明胶的得率,可为工业上骨明胶的生产提供有益的参考和借鉴。      

饮食文化下的陶瓷餐具设计

<正>在饮食文化中,陶瓷餐具作为重要的食器,承担着承托食物和展示交流的重要角色。设计陶瓷餐具时既要符合实用性和美观性的要求,还要体现各国、各地区文化的独特魅力。本文将探讨饮食文化下的陶瓷餐具设计原则,并提出具体的运用策略。     

Investigation on gain characteristics in non-degenerate cascaded phase sensitive parametric amplifiers

We theoretically and experimentally show the impact of the ratio between the signal and idler generated from the PIA part on the gain characteristics in the continuous wave (CW) pump non-degenerate cascaded phase-sensitive fiber optical parametric amplifier (PS-FOPA). The results show that the length of highly nonlinear fiber (HNLF) used for generating the idler can cause the variation of power ratio between the idler and signal, which significantly affects the gain characteristics of the PS-FOPA under the small signal gain condition. To obtain high gain, it is better to choose long HNLF to generate idler. In our experiment, 5.5 dB gain and 18 nm bandwidth (on/off gain>10 dBm) in PS-FOPA can be achieved when 300 m-long HNLF instead of 200 m-long HNLF is used in PIA.