Reanalysis of voyager 2 UVS occultations at Uranus: Hydrocarbon mixing ratios in the equatorial stratosphere

This paper studied the method for converting the aerosol extinction to the mass concentration of particulate matter (PM) and obtained the spatio-temporal distribution and transportation of aerosol, nitrogen dioxide (NO2), sulfur dioxide (SO2), and formaldehyde (HCHO) based on multi-axis differential optical absorption spectroscopy (MAX-DOAS) observations in Dalian (38.85°N, 121.36°E), Qingdao (36.35°N, 120.69°E), and Shanghai (31.60°N, 121.80°E) from 2019 to 2020. The PM2.5 measured by the in situ instrument and the PM2.5 simulated by the conversion formula showed a good correlation. The correlation coefficients R were 0.93 (Dalian), 0.90 (Qingdao), and 0.88 (Shanghai). A regular seasonality of the three trace gases is found, but not for aerosols. Considerable amplitudes in the weekly cycles were determined for NO2 and aerosols, but not for SO2 and HCHO. The aerosol profiles were nearly Gaussian, and the shapes of the trace gas profiles were nearly exponential, except for SO2 in Shanghai and HCHO in Qingdao. PM2.5 presented the largest transport flux, followed by NO2 and SO2. The main transport flux was the output flux from inland to sea in spring and winter. The MAX-DOAS and the Copernicus Atmosphere Monitoring Service (CAMS) models’ results were compared. The overestimation of NO2 and SO2 by CAMS is due to its overestimation of near-surface gas volume mixing ratios.

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Effect of pH and mixing ratios on the synergistic enhancement of Bambara groundnut-whey protein gels

Food Hydrocolloids ◽

10.1016/j.foodhyd.2021.106702 ◽

2021 ◽

pp. 106702

Author(s):

Claudine F. Diedericks ◽

Vanessa Stolten ◽

Victoria A. Jideani ◽

Paul Venema ◽

Erik van der Linden

Keyword(s):

Whey Protein ◽

Bambara Groundnut ◽

Effect Of Ph ◽

Mixing Ratios ◽

Synergistic Enhancement ◽

Protein Gels

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Assessment of Tropospheric Concentrations of NO2 from the TROPOMI/Sentinel-5 Precursor for the Estimation of Long-Term Exposure to Surface NO2 over South Korea

Remote Sensing ◽

10.3390/rs13101877 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1877

Author(s):

Ukkyo Jeong ◽

Hyunkee Hong

Keyword(s):

South Korea ◽

Spatial Resolution ◽

Atmospheric Composition ◽

Mixing Ratio ◽

Mean Values ◽

Mixing Ratios ◽

Tropospheric No2 ◽

Korean Ministry ◽

Surface Mixing ◽

Rural Sites

Since April 2018, the TROPOspheric Monitoring Instrument (TROPOMI) has provided data on tropospheric NO2 column concentrations (CTROPOMI) with unprecedented spatial resolution. This study aims to assess the capability of TROPOMI to acquire high spatial resolution data regarding surface NO2 mixing ratios. In general, the instrument effectively detected major and moderate sources of NO2 over South Korea with a clear weekday–weekend distinction. We compared the CTROPOMI with surface NO2 mixing ratio measurements from an extensive ground-based network over South Korea operated by the Korean Ministry of Environment (SKME; more than 570 sites), for 2019. Spatiotemporally collocated CTROPOMI and SKME showed a moderate correlation (correlation coefficient, r = 0.67), whereas their annual mean values at each site showed a higher correlation (r = 0.84). The CTROPOMI and SKME were well correlated around the Seoul metropolitan area, where significant amounts of NO2 prevailed throughout the year, whereas they showed lower correlation at rural sites. We converted the tropospheric NO2 from TROPOMI to the surface mixing ratio (STROPOMI) using the EAC4 (ECMWF Atmospheric Composition Reanalysis 4) profile shape, for quantitative comparison with the SKME. The estimated STROPOMI generally underestimated the in-situ value obtained, SKME (slope = 0.64), as reported in previous studies.

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Performance Optimisation of Fuel Pellets Comprising Pepper Stem and Coffee Grounds through Mixing Ratios and Torrefaction

Energies ◽

10.3390/en14154667 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4667

Author(s):

Sunyong Park ◽

Hui-Rim Jeong ◽

Yun-A Shin ◽

Seok-Jun Kim ◽

Young-Min Ju ◽

...

Keyword(s):

Calorific Value ◽

Basic Information ◽

Spent Coffee Grounds ◽

Mixing Ratios ◽

Moisture Contents ◽

Fuel Pellets ◽

Coffee Grounds ◽

Coffee Ground ◽

Fuel Characteristics ◽

By Products

Agricultural by-products have several disadvantages as fuel, such as low calorific values and high ash contents. To address these disadvantages, this study examined the mixing of agricultural by-products and spent coffee grounds, for use as a solid fuel, and the improvement of fuel characteristics through torrefaction. Pepper stems and spent coffee grounds were first dried to moisture contents of <15% and then combined, with mixing ratios varying from 9:1 to 6:4. Fuel pellets were produced from these mixtures using a commercial pelletiser, evaluated against various standards, and classified as grade A, B, or Bio-SRF. The optimal ratio of pepper stems to spent coffee grounds was determined to be 8:2. The pellets were torrefied to improve their fuel characteristics. Different torrefaction temperatures improved the mass yields of the pellets to between 50.87% and 88.27%. The calorific value increased from 19.9% to 26.8% at 290 °C. The optimal torrefaction temperature for coffee ground pellets was 230 °C, while for other pellets, it was 250 °C. This study provides basic information on the potential enhancement of agricultural by-products for fuel applications.

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