Total ozone column from Ozone Mapping and Profiler Suite Nadir Mapper (OMPS-NM) measurements using the broadband weighting function fitting approach (WFFA)

A scientific total ozone column product from Ozone Mapping and Profiler Suite Nadir Mapper (OMPS-NM) observations and the retrieval algorithm are presented. The retrieval employs the weighting function fitting approach (WFFA), a modification of the weighting function differential optical absorption spectroscopy (WFDOAS) technique. The total ozone columns retrieved with WFFA are in very good agreement with other datasets. A mean difference of 0.3 % with respect to ground-based Brewer and Dobson measurements is observed. Seasonal and latitudinal variations are well represented and in agreement with other satellite datasets. The comparison of our product with the operational product of OMPS-NM indicates a mean bias of around zero. The comparison with the Tropospheric Monitoring Instrument products (S5P/TROPOMI) OFFL and WFDOAS shows a persistent negative bias of about −0.6 % for OFFL and −2.5 % for WFDOAS. Larger differences are only observed in the polar regions. This data product is intended to be used for trend analysis and the retrieval of tropospheric ozone combined with the OMPS limb profiler data.

Total ozone column retrieval from OMPS-NM measurements

A scientific total ozone column product from the Ozone Mapping and Profiler Suite Nadir Mapper (OMPS-NM) observations and its retrieval algorithm are presented. The retrieval employs the Weighting Function Fitting Approach (WFFA), a modification of the Weighting Function Differential Optical Absorption Spectroscopy (WFDOAS) technique. The total ozone columns retrieved with WFFA are in very good agreement with other datasets. A mean difference of 0.6 % with respect to ground-based Brewer and Dobson measurements is observed. Seasonal and latitudinal variations are well represented and in agreement with other satellite datasets. The comparison of our product with the scientific product of OMPS-NM indicate a mean bias of around 0.1 %. The comparison with the Tropospheric Monitoring Instrument products (S5P/TROPOMI) OFFL and WFDOAS, shows a persistent negative bias of about −0.5 % for OFFL and –2 % for WFDOAS. Larger differences are only observed in the polar regions. This data product is intended to be used for trend analysis and the retrieval of tropospheric ozone combined with the OMPS limb profiler data.

Harvesting Marine Microalgae Nannochloropsis sp. using Dissolved Air Flotation (DAF) Technique

The production of high-value bioproducts from microalgae biomass has been widely investigated. However, their production is hindered by the expensive harvesting process. To date, flocculation followed by DAF process has been accepted as one of the affordable harvesting approaches. In this study, the use of DAF technique was attempted to harvest marine microalgae Nannochloropsis sp. Batch DAF harvesting was carried out using fabricated DAF unit equipped with several compartments including separation column, product collecting vessel and rotary skimmer. Tannin-based biopolymer flocculant, AFlok-BP1 at pH 5 with a concentration of 160 mg/L was used to facilitate the flocculation of particles. The effects of different saturator pressure at 1.8, 2, and 2.2 bar were then evaluated at a constant volume of 6 L microalgae culture. The effects of different microalgae culture volumes (6, 8 and 10 L) were also evaluated at a fixed saturator pressure of 2.2 bar. The highest pressure at 2.2 bar yielded the best result with the highest total solid of 3.19 ± 0.01% and a maximum yield of 1.70 ± 0.05 g/g (wet basis). The microalgae concentration was the lowest (0.027 g/L) when 6 L of culture volume was used. However, the values were significantly higher when the culture volume was increased to 8 and 10 L to approximately 0.035 and 0.050 g/L, respectively. As a conclusion, the study provided evidence for the feasibility of DAF technique in harvesting marine microalgae Nannochloropsis sp.

Technique for Evaluation of Gravity-Assisted Esophageal Transit Characteristics in Dogs with Megaesophagus

ABSTRACT Movement of food material in the esophagus during upright feeding in dogs with megaesophagus (ME) is poorly characterized. A standardized contrast videofluoroscopy technique was used to evaluate esophageal transit characteristics in dogs with ME while in an upright position. Twelve dogs with ME (congenital, acquired idiopathic, or secondary to myasthenia gravis) were placed in an upright position using Bailey chairs and given liquid barium, canned food meatballs, and their normal diet consistency if different than meatballs. Passage of ingesta was videofluoroscopically evaluated by direct observation and change in ingesta area as determined by manual tracing or barium column product calculations. Significant individual variation was seen. Complete esophageal clearance of liquid was seen in four dogs, and complete clearance of meatballs in three dogs, with a median time of 5 min for both. Two of seven dogs fed a slurry diet had complete clearance by 10 min. No significant difference was found between area calculated via tracing or barium column product. Based on imaging results, alterations in food consistency, duration upright, or medication were recommended for nine dogs. In dogs with ME accustomed to a Bailey chair, contrast videofluoroscopy was technically straightforward and allowed for more specific physician-guided management recommendations.

The Calculus of the Operation Parameters at Pressure of the Primary Separation Column of the 15N Production Plant

The relations for calculus of: 10M HNO3 solution flow, isotopic transport, 15N molar fraction at the bottom of the separation column, product flow, interphasic transfer velocity, height equivalent to the theoretical plate and sulfur dioxide flows in both stages of the product refluxer are presented for 15N separation column with different diameters and 10M HNO3 feeding flow rates, operated at pressure up to 1.5 atm. In order to produce the isotope 15N at 99 at. % 15N by isotopic exchange in Nitrox system it is desirable to operate the production plant at biggest flow of 10M HNO3 solution, which allows the 15N production at that concentration on a given plant. That will be possible by operating the plant at pressure as it is shown in this work. At 0.8 atm pressure (1.8 atm absolute) the isotopic separation at higher flow rates would be practically equal with that obtained at lower flow rates and atmospheric pressure. For constant: HETP = 10.85 cm, 15N molar fraction of the feeding 10M HNO3, Nf = 0.00365, and of the product, Np = 0.12, the variation of the primary separation column product and of the 15N production plant, as a function of the feeding flow with 10M HNO3 solution, are also presented.

Studies on Citronellal Extract Column Reflux Ratio and Theoretical Plate Number Design

In this paper, the batch rectification operation is adopted to keep distillate constituting constant high vacuum, in the operation process, the operation of variable reflux ratio is carries out. Through studying the relational system of reflux ratio, column top product composition, rectification time and theoretical plate number, when the concentration of citronellal extract column product is 99%, the appropriate reflux ratio is 0.8-15, and the graphic method is used to design13 pieces of theoretical plate number of citronellal extract column, providing powerful data support for the process design of citronellal extract column.

High Performance Unconstrained Word Recognition System Combining HMMs and Markov Random Fields

In this paper we present a system for the recognition of handwritten words on literal check amounts which advantageously combine HMMs and Markov random fields (MRFs). It operates at pixel level, in a holistic manner, on height normalized word images which are viewed as random field realizations. The HMM analyzes the image along the horizontal writing direction, in a specific state observation probability given by the column product of causal MRF-like pixel conditional probabilities. Aspects concerning definition, training and recognition via this type of model are developed throughout the paper. We report a 90.08% average word recognition rate on 2378 words and a 79.52% amount rate on 579 amounts of the SRTP* French postal check database (7031 words, 1779 amounts, different scriptors).

Gas Chromatography of Uracil Herbicides by On-Column Methylation with Trimethylanilinium Hydroxide

Substituted uracil herbicides injected into a gas chromatograph react with trimethylanilinium hydroxide to give iV-methyl derivatives with good gas chromatographic properties. Maximum methylation is obtained when the molar ratio of methylating reagent to herbicide is ca 4:1. This technique for preparing derivatives provides rapid qualitative and quantitative chromatography of the substances examined. Chromatographic response was linear with increased concentration for the synthetic standard and the on-column product of uracil herbicide. The proposed derivatization method was used to analyze herbicides in formulations. The methyl derivatives were identified spectroscopically

STUDIES ON PLASMINOGEN: I. FURTHER PURIFICATION OF BOVINE PLASMINOGEN

Crude bovine plasminogen, prepared from bovine serum by 30% saturation with ammonium sulphate, was partially purified by isoelectric precipitation at pH 5.3, then purified by chromatography on columns of diethylaminoethyl-cellulose. Additional purification of the column product was obtained by precipitation of plasminogen from solution with potassium phosphate. The most highly purified bovine plasminogen preparation, assaying 187 esterase units per mg nitrogen, represents a 28-fold purification of crude plasminogen. The over-all recovery from crude plasminogen was 15–20%. Sodium chloride inhibited crude plasminogen but had no effect on the activation of the most highly purified bovine plasminogen preparations. Bovine plasminogen could be spontaneously activated in 50% glycerol solution, but the degree of activation and the time required for maximum activation was also dependent on the purity of the preparation. Free boundary electrophoresis of purified preparations indicated that bovine plasminogen is associated with the major, faster-migrating component.