China
Africa
Explore chapters and articles related to this topic
Chemical Analysis in Environmental and Toxicological Chemistry
Published in Stanley E. Manahan, Environmental Chemistry, 2022
This chapter is designed to provide an overview of analytical chemistry as it applies to environmental chemistry. Whereas classical analytical chemistry involves measurements of mass (gravimetry) and of volumes (volumetric analysis), the current practice of analytical chemistry is largely based on the use of instruments (instrumental analysis). Modern analytical instruments are computer controlled and analytical data are processed by computer. Given the enormous number of pollutants and other substances that need to be determined in the hydrosphere, atmosphere, geosphere, biosphere, and anthrosphere, the literature of analytical chemistry fills many volumes. For those users who may become directly involved in doing chemical analyses, more detailed coverage of the topic and specific analytical procedures are discussed in reference works listed at the end of the chapter.
Ventilation of the Sealed Mining Excavation
Published in Ryszard Kłos, Ventilation of Normobaric and Hyperbaric Objects, 2021
The carbon dioxide content was measured with analytical heads of the POLYTRON IR CO2, which utilize IR7 spectroscopy. Infrared spectroscopy is a recognized and valued method of instrumental analysis, used for qualitative marking of organic compounds. The infrared spectra in the gas phase show only a slight widening of the absorption bands. This method can be used to detect trace amounts of organic compounds. Gases such as CO2 and CO give clear and well-distinguishable absorption bands, only partially overlapping. In the range of wavenumbers from 800–2000 cm−1, the spectrum is clear. This is called the range of fingerprint in which characteristic absorption bands of many organic compounds occur. Just as fingerprints differentiate people, bands in this range make it possible to distinguish chemical compounds as long as they can be properly interpreted. Similarly, in the range close to the wavelengths of approx. 3000 cm−1, the spectrum is clear. In this range, there are hydrocarbon absorption bands. Organic compounds that may be present in the breathing atmosphere, as products of metabolism, show high absorption activity in the ranges of wavenumbers 800–2000 cm−1 and approx. 3000 cm−1. In this way, they can be marked together with typical pollutants such as carbon dioxide and oxide.
Calibration, Verification, Quantification, Statistical Treatment of Analytical Data, Detection Limits, and Quality Assurance/Quality Control
Published in Paul R. Loconto, Trace Environmental Quantitative Analysis, 2020
Before samples are prepared and analytes quantitatively determined by instrumental analysis, the laboratory must demonstrate that the sample preparation bench-top area instrument itself and all reagents and solvents used are essentially free of traces of the targeted analyte of interest. This is accomplished by preparing method blanks using either distilled or deionized water or solvents of ultrahigh purity. This is particularly important for ultratrace analysis (i.e., concentration levels that are down to the low ppb or high ppt range). The use of pesticide residue analysis-grade solvents for conducting trace organics analysis and the use of ultratrace nitric and hydrochloric acids for trace metals analysis are strongly recommended. This author believes that there is a considerable number of organics in organic solvents at concentrations in the low ppt level! Nonzero blanks prevent true IDLs from ever being obtained. Nonzero blanks even affect analyte percent recoveries!
Desulfurization and De-ashing of Coal Through Catalytic Oxidation Using Fe (III) and Cu(II) Catalysts Loaded in Different Forms
Published in International Journal of Coal Preparation and Utilization, 2023
Waqas Ahmad, Imtiaz Ahmad, Ishraq Ahmad, Amjad Ali Shah
The instrumental analysis of the coal was carried out by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and X- Ray diffractometry (XRD). The surface morphology of the coal samples was investigated by scanning electron microscope (Model JEOL-JSM-5910; Japan), whereas the elemental analysis of the coal samples was investigated by using X-ray detector equipped with SEM (Srivastava, Jain, and Srivastava 2009). For recording the micrographs and elemental analysis, the powdered sample was mounted on carbon tape on steel stub and placed vacuum chamber below the radiation source. Mineral materials in coal sample were investigated by XRD analysis through X-ray Diffractometer, Model JDX-9C, JOEL. For X-ray diffraction analysis, the powdered sample on a slide was placed in the sample holder, the radiation source used was CuKα with k = 1.54178 Ao, and the diffraction pattern was recorded between 10 to 80 degrees 2 θ. The FTIR analysis was carried out using FTIR spectrophotometer (Model Schimadzu FTIR-820.1 PC), the sample was placed on ATR diamond, and an average of multiple scans was recorded between wave number of 400 to 4000 cm−1.
Sustainable biological system for the removal of high strength ammoniacal nitrogen and organic pollutants in poultry waste processing industrial effluent
Published in Journal of the Air & Waste Management Association, 2020
Thanmaya Mohan, Noorul Shaheen Sheik Farid, Swathi K.V., Sowmya A., Ramani K.
The initial physico-chemical parameters of the PWPI effluent such as COD and ammoniacal nitrogen content were estimated according to standard protocol as mentioned in American public health association (APHA) (APHA 1998). The protein and lipid concentration were estimated using Lowry’s method (Lowry et al. 1951) and Park et al. (2016), respectively. Instrumental analysis such as gas chromatography-mass spectroscopy (GC-MS), Fourier Transform Infrared Spectroscopy (FT-IR), and High-Performance Liquid Chromatography (HPLC) were performed to detect the presence of long chain fatty acids, functional groups, and amino acid compositions, respectively.