Mass spectrometry is widely used in flavour research to quantify compounds by using isotopically labelled internal standards. However, equimolar amounts of different molecules do not give equal instrumental responses. Therefore, calibration of the mass spectrometer is needed prior to any sample quantification. If the mass of the internal standard differs from that of the analyte by more than 3 ...

We describe the utilization of indocyanine green (ICG) dye to facilitate combined/en bloc removal of epiretinal membranes (ERM) along with internal limiting membranes (ILM). The method utilizes a highly diluted preparation of ICG in dextrose water solvent (D5W). Elimination of fluid air exchange step facilitating staining in the fluid phase and low intensity lighting help minimize potential ICG...

We present the performances of Li-based compounds used as scintillating bolometer for rare decay studies such as double-beta decay and direct dark matter investigations. The compounds are tested in a dilution refrigerator installed in the underground laboratory of Laboratori Nazionali del Gran Sasso (Italy). Low temperature scintillating properties are investigated by means of different radioac...

Commercial zein was base-hydrolyzed and purified extracts were subjected to gas chromatography-selected ion monitoring-mass spectrometry analysis. Indoleacetic acid (IAA) was shown to be released from this storage protein of corn (Zea mays). Isotope dilution using [(13)C(6)]IAA as an internal standard revealed a conservative ratio of 1 mole IAA to 175 moles zein. Immunoelectron micrographs of i...

An internal standard, [(13)C][indole-2]-indole-3-butyric acid, was synthesized from indole-2[(13)C] and was shown to be effective for the quantitative determination of indole-3-butyric acid from plant tissue. When this standard was used along with [(13)C(6)]indole-3-acetic acid, both indolic auxins could be quantified from the same tobacco (Nicotiana tabacam) leaf sample by isotope dilution ana...

The study of the gas nitriding method, which allows obtaining high-quality diffuse layers in high-speed steel P6M5 on basis an internal nitrogen hardening zone with no brittle nitride zone, has been viewed. Research results phase composition nitrided a change potential atmosphere during dilution ammonia are presented. Nitrided tool increased resistance drilling constructional and titanium alloy...

We propose that stress can decrease the internal friction of amorphous solids, either by increasing the potential barriers of defects, thus reducing their tunneling and thermal activation that produce loss, or by decreasing the coupling between defects and phonons. This stress can be from impurities, atomic bonding constraints, or externally applied stress. Externally applied stress also reduce...

The volatile components of Hallabong ([C. unshiu Marcov x C. sinensis Osbeck] x C. reticulata Blanco) cold-pressed peel oil were quantitatively and qualitatively determined by use of two internal standards with GC, GC-MS, and GC-olfactometry. According to instrumental analysis by GC and GC-MS, limonene (90.68%) was the most abundant compound, followed by sabinene (2.15%), myrcene (1.86%), and g...

Bilateral Jugular Venous Blood Flow by Thermal Dilution • Measurements of internal jugular venous flow were made in 12 patients with severe cerebral vascular disease. Flow rates were determined by the thermal dilution method, using room temperature physiological (heparinized) saline as an indicator infused at a constant rate. The major sources of error (indicator mixing) were studied under high...

A dilution method using MnO(2) for the manganese nodule standard, JMn1, has been newly adopted to obtain accurate calibration lines. Moreover, an internal standard correction method was applied to correct changes in the sample introduction efficiency for the prime purpose of laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analysis. Using the dilution method and the cor...