Reflective optical imaging for scattering medium using chaotic laser.

Significance: Optical imaging is a non-invasive imaging technology that utilizes near-infrared light, allows for the image reconstruction of optical properties like diffuse and absorption coefficients within the tissue. A recent trend is to use signal processing techniques or new light sources and expanding its application. Aim: We aim to develop the reflective optical imaging using the chaotic correlation technology with chaotic laser and optimize the quality and spatial resolution of reflective optical imaging. Approach: Scattering medium was measured using reflective configuration in different inhomogeneous regions to evaluate the performance of the imaging system. The accuracy of the recovered optical properties was investigated. The reconstruction errors of absorption coefficients and geometric centers were analyzed, and the feature metrics of the reconstructed images were evaluated. Results: We showed how chaotic correlation technology can be utilized for information extraction and image reconstruction. This means that a higher signal-to-noise ratio and image reconstruction of inhomogeneous phantoms under different scenarios successfully were achieved. Conclusions: This work highlights that the peak values of correlation of chaotic exhibit smaller reconstruction error and better reconstruction performance in optical imaging compared with reflective optical imaging with the continuous wave laser.

Two new CdII and ZnII coordination polymers incorporating 1-aminobenzene-3,4,5-tricarboxylic acid: synthesis, crystal structure and characterization.

Aminobenzoic acid derivatives are widely used in the preparation of new coordination polymers since they contain O-atom donors, as well as N-atom donors, and have a rich variety of coordination modes which can lead to polymers with intriguing structures and interesting properties. Two new coordination polymers incorporating 1-aminobenzene-3,4,5-tricarboxylic acid (H3abtc), namely, poly[(µ3-1-amino-5-carboxybenzene-3,4-dicarboxylato)diaquacadmium(II)], [Cd(C9H5NO6)(H2O)2]n, (I), and poly[[bis(µ5-1-aminobenzene-3,4,5-tricarboxylato)triaquatrizinc(II)] dihydrate], {[Zn3(C9H4NO6)2(H2O)3]·2H2O}n, (II), have been prepared and structurally characterized by single-crystal X-ray diffraction. In polymer (I), each tridentate 1-amino-5-carboxybenzene-3,4-dicarboxylate (Habtc2-) ligand coordinates to three CdII ions to form a two-dimensional network structure, in which all of the CdII ions and Habtc2- ligands are equivalent, respectively. Polymer (II) also exhibits a two-dimensional network structure, in which three crystallographically independent ZnII ions are bridged by two crystallographically independent pentadentate 1-aminobenzene-3,4,5-tricarboxylate (abtc3-) ligands. This indicates that changing the metal ion can influence the coordination mode of the H3abtc-derived ligand and further influence the detailed architecture of the polymer. Moreover, the IR spectra, thermogravimetric analyses and fluorescence properties were investigated.

Effect of pH on the construction of CdII coordination polymers involving the 1,1'-[1,4-phenylenebis(methylene)]bis(3,5-dicarboxylatopyridinium) ligand.

Changing the pH value of a reaction system can result in polymers with very different compositions and architectures. Two new coordination polymers based on 1,1'-[1,4-phenylenebis(methylene)]bis(3,5-dicarboxylatopyridinium) (L2-), namely catena-poly[[[tetraaquacadmium(II)]-µ2-1,1'-[1,4-phenylenebis(methylene)]bis(3,5-dicarboxylatopyridinium)] 1.66-hydrate], {[Cd(C22H14N2O8)(H2O)4]·1.66H2O}n, (I), and poly[{µ6-1,1'-[1,4-phenylenebis(methylene)]bis(3,5-dicarboxylatopyridinium)}cadmium(II)], [Cd(C22H14N2O8)]n, (II), have been prepared in the presence of NaOH or HNO3 and structurally characterized by single-crystal X-ray diffraction. In polymer (I), each CdII ion is coordinated by two halves of independent L2- ligands, forming a one-dimensional chain structure. In the crystal, these chains are further connected through O-H...O hydrogen bonds, leading to a three-dimensional hydrogen-bonded network. In polymer (II), each hexadentate L2- ligand coordinates to six CdII ions, resulting in a three-dimensional network structure, in which all of the CdII ions and L2- ligands are equivalent, respectively. The IR spectra, thermogravimetric analyses and fluorescence properties of both reported compounds were investigated.