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Ni-based catalysts have been widely used for the CO[sub.2] reforming of methane (CRM) process, but deactivation is their main problem. This study created an alternative electronic Ni-NiO-CeO[sub.2] interaction on the surface of 5 wt% Ni-5 wt% CeO[sub.2]/Al[sub.2]O[sub.3]-MgO (5Ni5Ce(xh)/MA) catalysts to enhance catalytic potential simultaneously with coke resistance for the CRM process. The Ni-NiO-CeO[sub.2] network was developed on Al[sub.2]O[sub.3]-MgO through layered double hydroxide synthesis via our ammonia vapor diffusion impregnation method. The physical properties of the fresh catalysts were analyzed employing FESEM, N[sub.2] physisorption, and XRD. The chemical properties on the catalyst surface were analyzed employing H[sub.2]-TPR, XPS, H[sub.2]-TPD, CO[sub.2]-TPD, and O[sub.2]-TPD. The CRM performances of reduced catalysts were evaluated at 600 °C under ambient pressure. Carbon deposits on spent catalysts were determined quantitatively and qualitatively by TPO, FESEM, and XRD. Compared to 5 wt% Ni-5 wt% CeO[sub.2]/Al[sub.2]O[sub.3]-MgO prepared by the traditional impregnation method, the electronic interaction of the Ni-NiO-CeO[sub.2] network with the Al[sub.2]O[sub.3]-MgO support was constructed along the time of ammonia diffusion treatment. The electronic interaction in the Ni-NiO-CeO[sub.2] nanostructure of the treated catalyst develops surface hydroxyl sites with an efficient pathway of OH* and O* transfer that improves catalytic activities and coke oxidation.

Atmospheric levels of ammonia (NH.sub.3) have substantially increased during the last century, posing a hazard to both human health and environmental quality. The atmospheric budget of NH.sub.3, however, is still highly uncertain due to an overall lack of observations. Satellite observations of atmospheric NH.sub.3 may help us in the current observational and knowledge gaps. Recent observations of the Cross-track Infrared Sounder (CrIS) provide us with daily, global distributions of NH.sub.3 . In this study, the CrIS NH.sub.3 product is assimilated into the LOTOS-EUROS chemistry transport model using two different methods aimed at improving the modeled spatiotemporal NH.sub.3 distributions. In the first method NH.sub.3 surface concentrations from CrIS are used to fit spatially varying NH.sub.3 emission time factors to redistribute model input NH.sub.3 emissions over the year. The second method uses the CrIS NH.sub.3 profile to adjust the NH.sub.3 emissions using a local ensemble transform Kalman filter (LETKF) in a top-down approach. The two methods are tested separately and combined, focusing on a region in western Europe (Germany, Belgium and the Netherlands). In this region, the mean CrIS NH.sub.3 total columns were up to a factor 2 higher than the simulated NH.sub.3 columns between 2014 and 2018, which, after assimilating the CrIS NH.sub.3 columns using the LETKF algorithm, led to an increase in the total NH.sub.3 emissions of up to approximately 30 %. Our results illustrate that CrIS NH.sub.3 observations can be used successfully to estimate spatially variable NH.sub.3 time factors and improve NH.sub.3 emission distributions temporally, especially in spring (March to May). Moreover, the use of the CrIS-based NH.sub.3 time factors resulted in an improved comparison with the onset and duration of the NH.sub.3 spring peak observed at observation sites at hourly resolution in the Netherlands. Assimilation of the CrIS NH.sub.3 columns with the LETKF algorithm is mainly advantageous for improving the spatial concentration distribution of the modeled NH.sub.3 fields. Compared to in situ observations, a combination of both methods led to the most significant improvements in modeled monthly NH.sub.3 surface concentration and NH4+ wet deposition fields, illustrating the usefulness of the CrIS NH.sub.3 products to improve the temporal representativity of the model and better constrain the budget in agricultural areas.

In the salt lake industry, large amounts of steamed ammonia liquid waste are discharged as byproducts. The conversion of the residues into high value-added vaterite-phase calcium carbonate products for industrial applications is highly desirable. In this research, the feasibility of preparing vaterite-phase CaCO[sub.3] in different CaCl[sub.2]-CO[sub.2]-MOH-H[sub.2]O systems using steamed ammonia liquid waste was studied in the absence of additives. The effects of initial CaCl[sub.2] concentration, stirring speed and CO[sub.2] flow rate on the composition of the CaCO[sub.3] crystal phase were investigated. The contents of vaterite were researched by the use of steamed ammonia liquid waste as a calcium source and pure calcium chloride as a contrast. The influence of the concentration of C[sub.NH3·H2O]/C[sub.Ca2+] on the carbonation ratio and crystal phase composition was studied. The reaction conditions on the content, particle size and morphology of vaterite influence were discussed. It was observed that single vaterite-phase CaCO[sub.3] was favored in the CaCl[sub.2]-CO[sub.2]-NH[sub.4]OH-H[sub.2]O system. Additionally, the impurity ions in steamed ammonia liquid waste play a key role in the nucleation and crystallization of vaterite, which could affect the formation of single-phase vaterite. The obtained results provided a novel method for the preparation of single vaterite particles with the utilization of CO[sub.2] and offered a selective method for the extensive utilization of steamed ammonia liquid waste.

BACKGROUND:Hepatic encephalopathy (HE) is a neuropsychiatric syndrome, a major complication of chronic liver disease (CLD/cirrhosis). The primary cause of hospital admissions for cirrhotic patients is an overt episode of HE. Precipitating factors of HE frequently lead to an increase in blood ammonia. Patients who have experienced multiple episodes of HE are associated with persisting neurological complications post-liver transplantation. Currently, the impact of HE episodes on neurological integrity is unknown. We hypothesize that multiple episodes of HE will accelerate and/or intensify neurological deterioration. To date, an animal model of episodic HE is lacking. Therefore, our goal was to characterize an animal model of episodic HE (precipitated with ammonia) and to evaluate the impact of cumulative episodes on neurological status in cirrhotic rats.METHODS:Animal model of CLD and HE: 6-week bile-duct ligation (BDL) rats, and Sham-operated controls were used. BDL and Sham rats were divided in two groups, episodic and non-episodic. Injection (i.p) of ammonium acetate was used to induce episodes of overt HE (pre-coma; loss of righting reflex) every 4 days starting 3-weeks post-BDL surgery (total 5 episodes). Saline was injected as vehicle for non-episodic groups. Two days following the last HE episode, we assessed motor-coordination (RotaRod), anxiety (elevated plus maze, EPMT), as well as short-term and long-term memory (novel object recognition) in all groups. Upon sacrifice, plasma ammonia was measured.RESULTS:The concentration of ammonia required to induce an episode of overt HE in BDL rats lessened with each subsequent episode, ranging from 7 to 4.5 mmol/kg. Short-term memory (P < 0.05) and motor-coordination (P < 0.05) were impaired in both non-episodic and episodic BDL groups compared to respective Sham-operated controls. Long-term memory impairment (P = 0.06) and increased anxiety (+60.0%, P < 0.05) were exclusively found in episodic BDL rats compared to non-episodic BDL rats. Moreover, there was an increase in blood ammonia (+30.4%, P = 0.06) in episodic compared to non-episodic BDL rats, suggesting that although episodic-BDL rats recover from each HE episode, baseline (pre-episode) ammonia remain higher than non-episodic BDL rats.CONCLUSIONS:Cumulative HE episodes escalate neurological impairments in cirrhotic-BDL rats. Thus, this new episodic HE model represents a good approach to explore the pathological mechanism arising from multiple episodes, as well as further investigate whether higher hyperammonemia and/or increased brain sensitivity to ammonia is responsible for more complex neurological manifestations in episodic-BDL rats. Moreover, this model is an excellent platform to investigate novel therapies to prevent/treat episodic HE.

The activated carbons (ACs) derived from okara powder waste with high surface areas were modified with ammonia aqueous solution impregnation in an autoclave to enhance their CO[sub.2] adsorption properties. The impregnated ACs were characterized, where the chemical composition and properties of the ACs were analyzed by SEM-EDX and FTIR. Activated carbons were functionalized with ammonia aqueous solution (25%) through a hydrothermal process within 24, 48, and 72 h. The adsorption performance of CO[sub.2] onto carbon samples was experimentally evaluated through a TPD CO[sub.2] measurement. FTIR spectra confirm the N-containing in N-modified activated carbons and the presence of the –C=O stretch and N-H groups. CO[sub.2] uptakes of activated carbons are 0.24; 1.78; 2.24; and 1.26 mmol/g, which are relatively comparable with those of activated carbons studied in the literature.

Ammonia (NH[sub.3]), which has a 17.7 wt% gravimetric hydrogen density, has been considered as a potential hydrogen storage material. This study looked at the thermocatalytic decomposition of NH[sub.3] using a bulk Mo[sub.2]N catalyst that was boosted by alkali metals (AM: 5 wt% Li, K, Cs). The K-Mo[sub.2]N catalyst outperformed all other catalysts in this experiment in terms of catalytic performance. At 6000 h[sup.−1] GHSV, 100% conversion of NH[sub.3] was accomplished using the K-Mo[sub.2]N, Cs-Mo[sub.2]N, and Mo[sub.2]N catalysts. However, when compared to other catalysts, K-Mo[sub.2]N had the highest activity, or 80% NH[sub.3] conversion, at a lower temperature, or 550 °C. The catalytic activity exhibited the following trend for the rate of hydrogen production per unit surface area: K-Mo[sub.2]N > Cs-Mo[sub.2]N > Li-Mo[sub.2]N > Mo[sub.2]N. Up to 20 h of testing the K-Mo[sub.2]N catalyst at 600 °C revealed no considerable deactivation.

The development of Ni/Zr-doped Al.sub.2O.sub.3 was achieved to reduce the reaction temperatures in ammonia decomposition by doping Zr into Al.sub.2O.sub.3 framework. The Ni/Zr-doped Al.sub.2O.sub.3 exhibits higher H.sub.2 yield and NH.sub.3 conversion than Ni/[gamma]-Al.sub.2O.sub.3 in a continuous operation. Partial doping of Zr in Al.sub.2O.sub.3 framework can increase Ni dispersion, Ni surface area and basic sites of the Ni catalyst. These effects can promote in both dehydrogenation of NH.sub.3 and recombination of nitrogen adsorbates in an NH.sub.3 decomposition mechanism. The comparison between roles of Zr as a dopant and a promoter for Ni catalyst was also discussed.

The aim of the study was to evaluate the effect of grazing Lolium perenne (Lp) and Bromus valdivianus (Bv) on the average daily weight gain (ADG) and nitrogen use efficiency (NUE) of Holstein Friesian heifers. Thirty heifers strip-grazed two pasture treatments (Lp and Bv) under a randomized complete block design (n = 3). Nutrient concentration and pasture intake were determined. Urine samples were taken, and the total volume of urine and microbial growth were estimated. Retained nitrogen (N), N intake, N excreted in feces and urine and the nitrogen use efficiency (NUE) were calculated. Lolium perenne showed greater WSC and ME but lower NDF than Bv, whereas crude and soluble protein were unaffected. There were no effects of species on ADG or feed conversion, and DMI was not affected by grass species, or the synthesis of microbial protein and purine derivatives. Ammonia in the rumen, urinary N and total N excreted were greater for heifers grazing Bv. In conclusion, the consumption of forage species did not alter the ADG or NUE of grazing heifers, but N partitioning was modified for heifers grazing Bv, due to the lower WSC/CP ratio compared with Lp.