鱼皮胶原蛋白的纯化及酶解性质的研究

分别对鲨鱼、鲢鱼、草鱼、罗非鱼鱼皮的胶原蛋白进行提取、纯化并进行SDS PAGE电泳分析,对它们的酶解性质进行研究.结果表明,提取的胶原蛋白有较高纯度,是典型的I型胶原蛋白.4种鱼皮胶原蛋白均能被胰蛋白酶和蛋白酶K水解,两种酶酶切位点有差异.不同鱼种鱼皮胶原蛋白的一级结构不同.本实验的酶解条件是适宜的

The Circuit Design of Piezoelectric Jetting Dispensing Control System

基于新型压电式点胶头采用的双压电陶瓷的推挽驱动作为胶体喷射的作用机制,设计并搭建了压电式喷射点胶控制系统,完成了硬件与软件模块的组装调试,实现对下压电陶瓷信号的频率、占空比、幅值、上压电陶瓷信号幅值的连续可调,具备人机交互、清洗、喷射点数可调等功能。经测试,系统各参数达到预定指标,频率显示误差:±1.2 Hz;占空比显示误差:±1%;幅值显示误差:±8 MV。在驱动方波电压200 V、频率65 Hz、占空比20%、喷嘴直径250μM、供料压力4 bAr、喷射高度3.5 MM的条件下,得到平均直径为1.07 MM左右的喷射胶滴,一致性误差为±2%。According to the working principle of newly piezoelectric dispensing head,which using the pushed driving of double piezoelectric ceramic for colloform jetting,we design and establish this piezoelectric jetting dispensing control system.Meanwhile,package the hardware and debug the software,achieve the goal that frequency,duty cycle and amplitude of the lower piezoelectric ceramic signal,amplitude of the upper piezoelectric ceramic signal can be continuously adjusted.The system has the function of man-machine interaction,cleaning,regulating injection points,and so on.After tested,all of the system parameters can meet the presupposed index,with the frequency display error: ±1.2 Hz,duty cycle display error: ±1%,amplitude display error: ±8 mV.Under the condition that voltage of the driving squarewave 200 V,frequency 65 Hz,duty cycle 20%,diameter of nozzle 250 μm,pressure 4 bar,height of jetting 3.5 mm,we get the jetting drops with an average diameter of 1.07 mm,and its conformity error ±2%.中央高校基金科研业务费专项资金资助项目(2010121039

Study on Low-temperature Si-Si Bonding Based on Combination of Dry and Wet Activation Methods

针对传统的硅片低温键合方法,提出了一种将湿法活化与等离子体干法活化相结合的硅片直接键合方法.通过工艺参数实验得到了在等离子体活化时间为90S、预键合施加负载为1 500n时可以实现较好的键合.之后进行了此法与干法活化和湿法活化的对比实验,结果表明此法在获得较高键合强度的同时可以明显减少采用干法时在退火后空洞的产生,满足后续工艺的使用要求.最后用干湿结合的方法实现了带腔体硅片的键合,弥补了湿法活化在硅片键合上的运用限制.Aimed at the traditional low-temperature silicon bonding methods,this article proposed another silicon direct bonding method combining the wet processes of activation with plasma dry of activation.A fine bonding quality can be achieved using the parameters of 90 s plasma activation time and 1 500 N prebonding pressure acquired by the process parameter experiment.Then a comparison experiment between this method and both the only dry and wet activation methods was presented.The consequence shows that this combination method can effectively avoid cavities that can be produced while using dry activation method after annealing,and a high bonding strength can be achieved at the same time.Subsequence application requirement can be meted in this way.At last,based on this combination of dry and wet activation method,the bonding of silicon and silicon with the hermetic cavity was realized making up for the limitation of wet activation method′s application.航空科学基金项目(20110868001); 惯性技术航空科技重点实验室资助项

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies