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Analyzer Sampling—Process Samples
Published in Béla G. Lipták, Analytical Instrumentation, 2018
W. M. Barrows, A. P. Foundos, B. G. Lipták
Processes are controlled by the application of automatic controls to produce higher quality, more uniform products; increase throughput; and protect the safety of personnel and property. An analyzer system enhances process control by providing specific measurement of physical or compositional data of a process or ambient conditions. With the advent of computer technology, the need for such analysis has increased substantially to provide on-line data that the computers can use to optimize process control.
Effect of sulfide on the nitrogen removal performance and microbial community of low-substrate Anammox process
Published in Environmental Technology, 2023
Na Chen, Xiao-jing Zhang, Deng-hui Wei, Yong-peng Ma, Nan Liu, Bing-bing Ma, Han Zhang, Hao-jie Yang
Ammonia was determined by Nessler's reagent spectrophotometry method, nitrite was determined using N-(1-naphthyl)-ethylenediamine spectrophotometry method, and nitrate using ultraviolet spectrophotometry method. Sulfide was detected using methylene blue spectrophotometry method. pH, DO, and temperature were determined by water quality analyzer (WTW, Germany). The total nitrogen removal efficiency (TNRE) was calculated as Equation (1): EPS and SMP were determined as follows: 7 mL mixed sludge was centrifuged at 8000 r/min for 15 min, then the supernatant was used to determine SMP. The residual sludge was diluted to the original volume with phosphate buffer solution (pH 7.0). After ultrasonic treatment for 3 min, the sample was heated for 30 min in a water bath at 80°C, and shaken evenly every 10 min. After cooling, it was centrifuged at 8000 r/min for 15 min and the supernatant was used for the determination of EPS. Subsequently, the contents of protein and polysaccharide in SMP and EPS were determined by Folin–phenol method and anthrone method [10].
Efficient crystallization process of dodecanedioic acid by a pneumatically agitated crystallizer
Published in Preparative Biochemistry & Biotechnology, 2023
Jiulong Duan, Li Chen, Rui Hong, Yanjun Li, Jin Huang
The CSD of crystal samples was determined by Malvern Mastersizer 3000 (Malvern Panalytical, UK) with laser diffraction. Parameters of laser crystal size analyzer were performed as follows: the refractive index was 1.392, the absorption rate was 0.01, and the shading degree was 0.5% ∼ 15%. The median crystal diameter was expressed as Dv50 and the product yield was calculated as following equation: in which m1 and m0 are the final crystal weight and the initial crude DC12 weight, respectively. P1 and P0 are the final crystal purity and initial crude DC12 purity, respectively. All experiments were performed in triplicate, and the results were presented as the mean ± SD.
Degradation of antimicrobial resistance genes within stockpiled beef cattle feedlot manure
Published in Journal of Environmental Science and Health, Part A, 2021
Shanwei Xu, Tim Schwinghamer, Srinivas Sura, Allan J. Cessna, Francis Zvomuya, Rahat Zaheer, Francis J. Larney, Tim A. McAllister
Fresh manure on d 0, as well as sub-samples from mesh bags retrieved from stockpiles on d 7, 26, 56 and 102 (150 g) were placed into 500-mL Whirl-Pak® bags, weighed, and stored at −25 °C. Before analysis, samples were freeze-dried for 7 d and weighed to determine moisture content. For each sample, wet manure (10 g) was added to 200 mL of deionized water and thoroughly mixed for 1 h, and pH of the mixture was measured using a pH meter (Model Multi 340i, WTW). Subsequently, samples were centrifuged at 10,000 × g for 15 min and the extract was used to measure electrical conductivity (Model 125; Orion, Beverly, MA). Mineral N (NH4-N and NO3-N) of the extract was measured using an auto analyzer (AutoAnalyzer III, Bran + Luebbe GmbH, Norderstedt, Germany). For total carbon (TC) and total nitrogen (TN), the freeze-dried samples used for moisture content determination were ground to pass through a 2-mm screen using a Model 4 Wiley Mill (GMI Inc.). A subsample was further ground to <150 μm using a ball mill (model MM2000, Retsch GmbH, Haan, Germany). Subsamples were used to determine TC and TN by dry combustion using a CNS analyzer (NA-1500, CE Instruments).