Search results
Results From The WOW.Com Content Network
In positive ion mode, DART produces predominantly protonated molecules [M+H] + and in negative-ion mode deprotonated molecules [M-H] −. Both negative and positive modes of DART provides relatively simple mass spectra. Depending on the type of analyte, other species may be formed, such as multiple charged adducts. DART is categorized as a soft ...
Software by NIST for compression of structure with mass spectra. The program seeks to find mechanisms and their rates for all fragmentation types (EI, Tandem positive and negative mode) and correlates mass spectral peaks to a probable origin structure. It contains an isotope calculator and other features and on-line help.
In the negative mode, [M−H] − ions are produced by either proton abstraction, or [M+X] − ions are produced by anion attachment. Most work on the APCI-MS analysis has been in positive mode. In the positive mode, when the discharge current of corona discharge is 1-5 μA on the nebulized solvent, N 2 gas molecules are excited and ionized ...
Chemical ionization for gas phase analysis is either positive or negative. [12] Almost all neutral analytes can form positive ions through the reactions described above. In order to see a response by negative chemical ionization (NCI, also NICI), the analyte must be capable of producing a negative ion (stabilize a negative charge) for example ...
The mass range is the range of m/z amenable to analysis by a given analyzer. The linear dynamic range is the range over which ion signal is linear with analyte concentration. Speed refers to the time frame of the experiment and ultimately is used to determine the number of spectra per unit time that can be generated.
A nickel–hydrogen battery (NiH 2 or Ni–H 2) is a rechargeable electrochemical power source based on nickel and hydrogen. [5] It differs from a nickel–metal hydride (NiMH) battery by the use of hydrogen in gaseous form, stored in a pressurized cell at up to 1200 psi (82.7 bar ) pressure. [ 6 ]
It is also less prone to ion suppression and matrix effects compared to ESI and APCI and typically has a wide linear dynamic range. The application of APPI with LC/MS is commonly used for analysis of petroleum compounds, pesticides, steroids, and drug metabolites lacking polar functional groups and is being extensively deployed for ambient ...
Indeed, both the negative (lithium metal) and the positive (air or oxygen) electrodes are the reasons why, respectively, rechargeable lithium-metal batteries failed to reach the market in the 1970s (the lithium-ion battery in a mobile device uses a LiC 6-graphite compound on the negative electrode, not a lithium metal).