Improved detection limits for electrospray ionization on a magnetic sector mass spectrometer by using an array detector

Array detection was compared with point detection for solutions of hen egg-white lysozyme, equine myoglobin, and ubiquitin analyzed by electrospray ionization with a magnetic sector mass spectrometer. The detection limits for samples analyzed by using the array detector system were at least 10 times lower than could be achieved by using a point detector on the same mass spectrometer. The minimum detectable quantity of protein corresponded to a signal-to-background ratio of approximately 2∶1 for a 500 amol/μL solution of hen egg-white lysozyme. However, the ultimate practical sample concentrations appeared to be in the 10–100 fmol/μL range for the analysis of dilute solutions of relatively pure proteins or simple mixtures.     

Small visible energy scalar top iterative discriminant analysis

Light scalar top quarks with a small mass difference with respect to the neutralino mass are of particular cosmological interest. This study uses an iterative discriminant analysis method to optimize the expected selection efficiency at the international linear collider (ILC).      

Measurement of flow visualized on surface of bubble blown in air

Bubbles blown in surfactant (frother) solution reveal surface flows attributed to gravity drainage and opposing Marangoni Effect. A technique is introduced to visualize the flows and estimate trajectory velocity. The flow pattern and velocity depend on frother type (pentanol vs. a polyglycol) and concentration but no correlation with surface tension was found. The relevance of the observations to the action of frother in flotation is briefly discussed.     

Gamma gamma technology group

The results presented at this conference in the γγ technology group are described.      

An excellent reagent for the removal of the t-butyldimethylsilyl protecting group

Aqueous hydrofluoric acid is an excellent reagent for the removal of $\text{t}$-butyldimethylsilyl protecting groups.     

A differential scanning calorimetric study of cysteine hydrochloride monohydrate

An irreversible phase change, ΔH (transition) = 5.44 ± 0.11 kcal mol^?1 at 337.1 ± 0.3 K has been confirmed in L-(+)-cysteine hydrochloride monohydrate. Phase transitions resulting from thermal pretreatment are also reported and discussed.     

Ultrasonic flaw detection in model railway wheels

Rayleigh and Lamb waves have been excited in $\text{1}\text{4}$ scale model railway wheels by an ultrasonic source located on the wheel tread. Simulated flaws in treads and plates have been located.