Phase equilibrium analyzer

Rapid, Automated Solubility and Phase Behavior Studies
Thar's Phase Equilibrium Analyzer is likely the most automated and sophisticated in the world. The system includes a cutting edge PC controlled vessel system that allows the user to control pressure, temperature and density. Simple to use and install, the motorized variable volume vessel combines with a PC-controlled high pressure syringe pump, camera system, heating bath, TV/VCR and PC with Thar software to create a turnkey solution. Many scientists and managers are curious as to how products react, crystallize, mix, disperse and dissolve in supercritical media. For them, the solution is the Thar PEA.
Advantages:
■ Rapid generation of solubility data
■ Ideal for process development
■ No extraction efficiency issues
■ No collection issues
■ New insights into the mechanism
■ Data logging during the process
■ Only H.P. Viewing Instrument with automated, moving plunger with an attached agitator
Benefits:
■ Helpful for studying GAS (Gas Anti-Solvent Precipitation Technique
■ SAS simulations possible (Supercritical Anti-Solvent)
■ Useful in studying how surfactants and solvents behave under pressure
■ Viewing reactions, dissolutions, crystallization
■ Rapidly saves time on process scale-up



http://www.thartech.com/

Magnetic Tunnel Junction

A magnetic tunnel junction (MTJ) consists of two layers of magnetic metal, such as cobalt-iron, separated by an ultrathin layer of insulator, typically aluminum oxide with a thickness of about 1 nm. The insulating layer is so thin that electrons can tunnel through the barrier if a bias voltage is applied between the two metal electrodes. In MTJs the tunneling current depends on the relative orientation of magnetizations of the two ferromagnetic layers, which can be changed by an applied magnetic field. This phenomenon is called tunneling magnetoresistance (TMR).

Nowadays MTJs that are based on transition-metal ferromagnets and Al₂O₃ barriers can be fabricated with reproducible characteristics and with TMR values up to 50% at room temperature. Recently large values of TMR observed in crystalline MTJs with MgO barriers further boosted interest in spin dependent tunneling. MTJs are promising for applications in magnetic storage and sensor industry.

http://physics.unl.edu/~tsymbal/tsymbal_files/TMR/sdt_files/page0001.html

Bio-functionalized of Monodisperse Magnetic Nanoparticles and Their Use as Biomolecular Lables in a Magnetic Tunnel Junction Based Sensor

Stephanine G. Grancharov, Hao Zeng, Shouheng Sun, Shan X. Wang, Stephen O'Brien, C. B. Murray, J. R. Kirtley, and G. A. Held
J. Phys. Chem. B
2005, 109, 13030-13035
Abstract : NPs(monodisperse magnetic nanoparticles)能以超靈敏磁性來偵測生物分析物，然而要使這些粒子有生物相容性是一個挑戰。我們報導12nm錳鐵NPs的生物功能性及偵測，能在卵白素二氧化矽基材及互補DNA二氧化矽基材上獲得有位置特異性鍵結的維生素H功能性NPs。利用掃描式SQUID顯微鏡，顯示那些與基材結合的NPs仍具有磁性，示範了一種在室溫使用NPs及適用於垂直磁場的磁性穿隧接點生物感測器(magnetic tunnel-junction-based biosensor)來檢測蛋白質鍵結或DNA雜交的新方法。

SQUID－大倫學長整理

SQUID2a.JPG

SQUID2b.JPG







Gmix.JPG

Gzero.JPG





Dear 筱沁,
附件是重新處理過的 SQUID 數據 並且將結果與千惠的結果比對
圖2b 的結果合理，說明此次量測儀器應無異常, 隨溫度增加其飽和磁量會下降 ( 2.3 -> 0.7~0.3)
比對千惠的之雜交後之結果，飽和磁量下降頗多，有幾個可能：
(1) 取出之樣品中MNP的濃度偏低
(2) 雜交之結果顯著抑制了飽和磁量
(3) 系統性偏差
屏除第三點暫且不論，假設(2)成立則殘磁量亦應隨之增加
比對圖2b則殘磁反倒下降一個數量級 (~6e-3)
這個結果則印證假設一比較可能成立。
結論：妳跟我說你的步驟，妳在旁邊看我有沒有重覆錯誤，我來重作一次，之後重新送一次分析，連同空白
若有任何想法，煩請與我連絡
大倫

Density Measurement of Polymer/CO2 Single-Phase Solution at High Temperature and Pressure using a Gravimetric Method

Euta Funami, Kentaro Taki, Masahiro Ohshima

Department of chemical Engineering, Kyoto University Japan, Kyoto, Japan 615-8510

Journal of Applied Polymer Science, Vol. 105, 3060-3068(2007)

ABSTRACT:
在高於聚合物熔點的溫度以及CO2壓力範圍0~15MPa，使用新提出的重力測量法量測聚合物/CO2單相溶液的密度。在高壓CO2下，使用磁懸浮天平(magnetic suspension balance, MSB)量測密度：一薄盤狀鉑板被浸入盛有聚合物/CO2單相溶液的MSB高壓室。將吸收室保持CO2壓力及溫度下測板重，因為聚合物/CO2單相溶液對板子施浮力而使板子重量減輕，即可從板子重量的差值算出聚合物/CO2單相溶液的密度。實驗結果顯示，PE/CP2溶液的密度隨CO2壓力上升而增加，而PEG/CO2溶液的密度則隨CO2壓力上升而減少。為了將CO2溶解於聚合物的效應以及機械壓力的效應區別開來，比較聚合物/CO2溶液的密度與承受機械壓力的純聚合物密度(以Sanchez-Lacombe 狀態方程式以及聚合物的壓力-體積-溫度資料來計算)。比較結果可以說明CO2溶解於聚合物會減少PEG/CO2及PE/CO2系統的密度，但兩者減少的程度不同。

重力測量法

重力測量法(力學測量法)：利用自由落體公式(S=1/2 G T2 其中G為重力加速度，大約為9.8 公尺/秒平方；T為物體自由落下所需時間，單位為秒)，在高處自由投下一物體，利用其落下花費時間，估算出所在處高度。
http://www.ied.edu.hk/apfslt/v5_issue2/chencc/chencc4.htm