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List of Chemical Substances
Published in T.S.S. Dikshith, and Safety, 2016
Exposures to methylene chloride cause adverse health effects and poisoning to users. Methylene chloride harms the human CNS. The symptoms of poisoning include, but are not limited to, dizziness, nausea, tingling, and numbness in the fingers and toes. Laboratory animals exposed to very high levels of methylene chloride suffer unconsciousness and fatal injury/death. Occupational workers who are exposed to direct skin contact with methylene chloride indicate symptoms of intense burning and mild redness of the skin, damage to the eyes and cornea.
Toxic Substances and Hazardous Wastes
Published in Frank R. Spellman, Kathern Welsh, Safe Work Practices for Wastewater Treatment Plants, 2018
Frank R. Spellman, Kathern Welsh
Methylene chloride—Employees exposed to methylene chloride are at increased risk of developing cancer; they may also suffer adverse effects on the heart, central nervous system, and liver, as well as skin or eye irritation. Exposure can occur through inhalation, by absorption through the skin, or through contact with the skin. Methylene chloride is a solvent used in many diverse types of work activities, such as paint stripping, polyurethane foam manufacturing, cleaning, and degreasing.
Toxicity of Solvents
Published in Lorris G. Cockerham, Barbara S. Shane, Basic Environmental Toxicology, 2019
Methylene chloride is used as a solvent for oils, fats, and waxes and is also widely used as an aerosol propellant, paint remover, and degreaser. NIOSH estimates that 70,000 workers are exposed to methylene chloride annually, and it is classified by the EPA as a potential carcinogen, hazardous waste, and priority pollutant (Settig, 1985).
Stacking interactions in cavity-containing molecular structures built from acylphloroglucinols: a computational study
Published in Molecular Physics, 2021
Another aspect of the geometry description of these structures is the angle of the methylene bridge between monomers. Table S4 reports the changes in the values of this angle prompted by the introduction of the Grimme correction into the calculations. For bowls with Cnv symmetry, the angle decrease slightly, mostly by 0.5−0.7o. For esa-bowls, the decrease is greater for the angles close to the narrower parts of the bowls (mostly ≈1.4o for C3A−C9 A−C5B and 1.3−1.7 for C3C−C9 C−C5D) and smaller (≈0.3o) for the angles in the middle region of the longer side of the bowl (C3B−C9 B−C5C). For tt-tetra-A, tt-tetra-B, tt-tetra-C and tt-tetra-D tubes, the angle decreases by 1.0−1.3o; for esa-tubes, it mostly decreases (by 1.0−1.9o), but it increases slightly for tt-esa-A-1, tt-esa-B1 and tt-esa-D1.
Synthesis, characterization, and catalytic activity of a new series of Ni(II), Cu(II), and Zn(II) complexes of N,N-O,O mixed-bidentate ligands for C–C cross-coupling reactions
Published in Journal of Coordination Chemistry, 2018
Govindasamy Vinoth, Sekar Indira, Madheswaran Bharathi, Arumugam Nandhakumar, Kannappan Sathishkumar, Kuppannan Shanmuga Bharathi
Infrared spectra of the complexes show several bands from 400 to 4000 cm−1. The spectrum of the uncoordinated ligand shows the phenolic O–H stretch at 3316 cm−1 and phenolic C–O stretch at 1279 cm−1; the ligand also displays a band at 1486 cm−1 corresponding to the ArCH2 stretch, indicating the formation of bisphenol through a CH2 linkage. The coordination of metal ion through bisphenolic oxygens is affirmed by the disappearance of phenolic O–H band [41] with an increase in C–O stretching frequency from 1279 to 1282 cm−1 for the Ni(II) complex (1). There is a band at 1487 cm−1 corresponding to methylene (CH2) stretch consistent with the methylene bridge [45]. The same trend is observed in 2–6. The appearance of N–H stretch at 3217 cm−1 indicates the non-deprotonation of the piperazine protons in 4–6 [46]. All the complexes show strong bands at 400–450 and 500–550 cm−1 corresponding to M–N and M–O, respectively [47, 48].
Oil-in-gold nanoparticle solution emulsion stabilized with amphiphilic polymers and its stability under NIR irradiation
Published in Journal of Dispersion Science and Technology, 2018
Figure 2 shows the 1H NMR spectrum of P(HEA/PMA)(100/0) and P(HEA/PMA)(90/10). According to the 1H NMR spectrum of P(HEA/PMA)(100/0), the vinyl methylene group was found at 1.764 ppm (a), the vinyl methine group was found at 2.396 ppm (b), the methylene group next to the hydroxyl group was found at 3.749 ppm (d), and the methylene group adjacent to the ester bond was found at 4.154 ppm (c). According to the 1H NMR spectrum of P(HEA/PMA)(90/10), the methyl group of PMA was found at 1.050 ppm (f) and 0.919 ppm (i), the vinyl methylene group was found at 1.856 ppm (e) and 1.617 ppm (a), the methylene group next to the methyl group of PMA was found at 1.950 ppm (h), the vinyl methine group of HEA was found at 2.397 ppm (b), the methylene group next to the hydroxyl group of HEA was found at 3.737 ppm (d), and the methylene group adjacent to the ester bond was found at 4.139 ppm (c) and 4.130 ppm (g). Using the signal area of the methylene group next to the methine group of HEA (b) and that of the methyl group of PMA (f, i), the HEA to PMA molar ratio was calculated to be 100:9.4. The signals on the 1H NMR spectra of the other P(HEA/PMA)s were in almost the same position as those observed on the spectrum of P(HEA/PMA)(90/10). The HEA to PMA molar ratio of P(HEA/PMA)(97/3), P(HEA/PMA)(95/5), and P(HEA/PMA)(93/7) was calculated to be 100:3, 100:3.4, and 100:6.5, respectively.