Non-metal cation (NMC) pentaborate structures, in which some amino acids (valine, leucine, isoleucine, and threonine) were used as cations, were synthesized. The structural characterization of molecules was carried out by elemental analysis, FT-IR, mass, 11B-NMR, and thermal analysis (TGA/DTA) methods. The hydrogen storage capacity of molecules was also calculated by taking experimental results into consideration. The FT-IR spectra support the similarity of structures. The characteristic peaks attributable to pentaborate rings and amino acids were observed. When thermal analysis data were examined, it was observed that pentaborate salts gave similar degradation steps and degradation products. As a final degradation product of all thermal analysis experiments, a glassy form of B2O3 was observed. The valine pentaborate is the most thermally stable. Also, the amounts of hydrate water outside the coordination sphere of the compounds were determined by thermal analysis curves. The peaks of boric acid, triborate, and pentaborate structures were obtained in ppm with the 11B-NMR results of synthesized pentaborate compounds. With powder X-ray spectroscopy, all structures were found to be crystalline but not suitable for single-crystal X-ray analysis. The molecular cavities of the compounds detected by BET were found to be 3.286, 1.873, 2.309, and 1.860 g/cm3, respectively. A low number of molecular cavities can be interpreted in several existing hydrogen bonds in structures. The hydrogen storage capacities of the molecules were found to be in the range of 0.04 to 0.07% by mass.

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The pK a values of cefdinir and cefixime, which are used in the treatment of bacterial infections, have been determined precisely in water and methanol-water binary mixtures (20% v/v) using spectrophotometric titration and LC, respectively. A simple, fast and precise isocratic highperformance liquid chromatographic (LC) procedure has been developed for the determination of cefdinir and cefixime in drug formulations. This method was validated successfully for specificity, precision, linearity, range, accuracy, limit of detection, and limit of quantitation as per the ICH guidelines. The proposed method can be used for routine analysis of studied cephalosporin compounds and as an alternative tool for drug quality control laboratories.

B oron is a chemical element with symbol B and atomic number 5. Because boron is produced entirely by cosmic ray spallation and not by stellar nucleosynthesis, it is a low-abundance element in both the Solar system and the Earth's crust [1]. In biology, borates have low toxicity in mammals (similar to table salt), but are more toxic to arthropods and are used as insecticides. Boric acid is mildly antimicrobial, and a natural boroncontaining organic antibiotic is known [2]. The earliest routes to elemental boron involved reduction of boric oxide with metals such as magnesium or aluminum. However the product is almost always contaminated with metal borides. Pure boron can be prepared by reducing volatile boron halides with hydrogen at high temperatures. Ultrapure boron for use in the semiconductor industry is produced by the decomposition of diborane at high temperatures

Nonmetal cation (NMC) pentaborate structures were synthesized using the amino acid molecules as cations precursors. Chemical composition analysis, infrared spectroscopy, mass analysis, boron nuclear magnetic resonance, and thermal gravimetric analysis (TGA/DTA) methods were used for structural characterization. The hydrogen storage efficiency of molecules was also determined experimentally. The recorded infrared spectra support the structural similarities of the molecules. Stretchings of pentaborate rings and characteristic peaks of amino acids were detected in infrared spectra. When the thermal analysis curves were recorded, it was found that the structures showed similar decomposition steps. Due to the result of thermal decay, glassy boron oxide (B 2 O 3) formation was observed as the final decomposition products of all molecules. Peaks associated with boric acid, triborate, and pentaborate were observed in the 11 B spectra of these salts. Powder X-ray diffraction spectroscopy supports the presence of BO 3 and BO 4 − groups regarding the presence of pentaborate rings. It also indicates the high crystallinity of the structures. The molecular cavities detected by brunauer-emmett-teller analysis were found to be 3.586, 1.922, 1.673, and 1.923 g/cm 3. Low-molecular cavities can be attributed to the high hydrogenbonding capacity of the structures. The hydrogen capture efficiency of the pentaborate salts was found to be in the range of 0.039-0.