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Other than using infinite basis sets, two methods exist to eliminate the BSSE. In the chemical Hamiltonian approach (CHA), [ 4 ] [ 5 ] basis set mixing is prevented a priori , by replacing the conventional Hamiltonian with one in which all the projector -containing terms that would allow mixing have been removed.
Endomicroscopy is a technique for obtaining histology-like images from inside the human body in real-time, [1] [2] [3] a process known as ‘optical biopsy’. [ 4 ] [ 5 ] It generally refers to fluorescence confocal microscopy , although multi-photon microscopy and optical coherence tomography have also been adapted for endoscopic use.
This is a list of unsolved problems in chemistry. Problems in chemistry are considered unsolved when an expert in the field considers it unsolved or when several experts in the field disagree about a solution to a problem.
Confocal endoscopy, or confocal laser endomicroscopy (CLE), is a modern imaging technique that allows the examination of real-time microscopic and histological features inside the body. In the word "endomicroscopy", endo- means "within" and -skopein means "to view or observe".
This is the same phenomenon used in two-photon microscopy (TPM), but there are two key features that distinguish pump–probe microscopy from TPM. First, since the molecule is not necessarily fluorescent, a photodetector measures the probe intensity. Therefore, the signal decreases as two-photon absorption occurs, the reverse of TPM. [3]
The analysis of results is performed by determining the ratio of elements from within the sample and working out a chemical formula that fits with those results. This process is useful as it helps determine if a sample sent is the desired compound and confirms the purity of a compound.
This has led to informal use the two terms as interchangeable, especially because optical purity was the traditional way of measuring enantiomeric excess. However, other methods such as chiral column chromatography and NMR spectroscopy can now be used for measuring the amount of each enantiomer individually.
Erythrose is a tetrose saccharide with the chemical formula C 4 H 8 O 4. It has one aldehyde group, and is thus part of the aldose family. The natural isomer is D-erythrose; it is a diastereomer of D-threose. [3] Fischer projections depicting the two enantiomers of erythrose