ammonia concentration
Recently Published Documents


TOTAL DOCUMENTS

929
(FIVE YEARS 219)

H-INDEX

52
(FIVE YEARS 5)

2022 ◽  
Vol 9 ◽  
Author(s):  
Yicen Zhang ◽  
Yang Du ◽  
Xiaochen Lu ◽  
Pan Zhao ◽  
Yiping Dai

The wide utilization of solar energy is beneficial for the emission reduction of carbon dioxide. This paper proposes a novel power cycle system driven by solar energy, which consists of a recompression supercritical carbon dioxide cycle (RSCO2) and an ammonia-water cooling-power cycle (ACPC). The power system operates in a “self-production and self-sale” mode, which means that the refrigeration capacity produced by the ACPC is utilized to cool the main compressor inlet fluid of the RSCO2. The comprehensive energy and exergy analyses of the proposed novel system are presented. The effects of the six parameters on the system thermodynamic performance are evaluated, which are direct normal irradiation, the ammonia concentration of a basic solution, the pinch point temperature difference of an evaporator, the effectiveness of a recuperator, the pressure ratio of the RSCO2 and the molten salt outlet temperature. The results show that compared with the stand-alone RSCO2, the net power and energy efficiency of the proposed system are improved by 15.94 and 10.61%, respectively. In addition, the increasing ammonia concentration of the basic solution leads to the rise of the ACPC refrigeration output, and the inlet temperature of the main compressor can be declined to 32.97°C with the ammonia concentration of the basic solution of 0.88. Moreover, when the effectiveness of the recuperator in RSCO2 rises up to 0.98, the system energy and exergy efficiencies can reach their maximum value of 30.68 and 33.10%, respectively.


2022 ◽  
Vol 956 (1) ◽  
pp. 012014
Author(s):  
S Siddiq ◽  
Saiful ◽  
N Arahman

Abstract The 2004 earthquake off the west coast of Aceh caused a catastrophic tsunami. The massive influx of seawater into the land affected the environment, especially groundwater. Kuta Alam was one of the sub-districts worst affected by the tsunami. In 2005 and 2006, the quality of groundwater degraded due to, among others, the content of ammonia compounds. Increasing the population density after city reconstruction became a problem for the environment as domestic waste also pollutes the groundwater. This study proved that while 2 of the 3 research samples showed a decrease in the level of ammonia compounds in groundwater. One sampling in a densely populated area showed an increase of ammonia concentration. In areas that are not densely populated, ammonia compounds have diluted to an acceptable level, but an increase was found in densely populated areas. This indicated that the pollution was most likely occur around high population area. Proofing through a simple linear regression analysis showed a strong correlation between the content of ammonia compounds and population density.


2022 ◽  
Vol 951 (1) ◽  
pp. 012004
Author(s):  
S Nayohan ◽  
K G Wiryawan ◽  
A Jayanegara

Abstract The aim of this study was to determine the effect of coating urea by chitosan at graded levels on ammonia concentration and rumen fermentation in vitro. This study used Factorial Randomized Complete Block Design (RCBD) to test ammonia parameter and Randomized Complete Block Design (RCBD) for pH, microbial protein synthesis, dry matter and organic matter digestibility, and Volatile Fatty Acid (VFA). The treatments tested were: P0 = addition non coating urea 1%; P1 = coating urea by chitosan 1%; P2 = coating urea by chitosan 2%; P3 = coating urea by chitosan 3%. The data obtained were analysed by using ANOVA and continued with Tukey HSD test with SPSS version 25. The results of this study showed that the coating of urea chitosan had no significant effect on pH, dry matter and organic matter digestibility, microbial protein synthesis, and amonia concentration in the rumen. However, it significantly reduced (P <0.05) total VFA concentration. It can be concluded that the application of urea coating by chitosan does not affect on the degradation of urea in the rumen.


2021 ◽  
Author(s):  
Yosra Ahmed Soltan ◽  
Amlan Kumar Patra

The rumen is an integrated dynamic microbial ecosystem composed of enormous populations of bacteria, protozoa, fungi, archaea, and bacteriophages. These microbes ferment feed organic matter consumed by ruminants to produce beneficial products such as microbial biomass and short-chain fatty acids, which form the major metabolic fuels for ruminants. The fermentation process also involves inefficient end product formation for both host animals and the environment, such as ammonia, methane, and carbon dioxide production. In typical conditions of ruminal fermentation, microbiota does not produce an optimal mixture of enzymes to maximize plant cell wall degradation or synthesize maximum microbial protein. Well-functioning rumen can be achieved through microbial manipulation by alteration of rumen microbiome composition to enhance specific beneficial fermentation pathways while minimizing or altering inefficient fermentation pathways. Therefore, manipulating ruminal fermentation is useful to improve feed conversion efficiency, animal productivity, and product quality. Understanding rumen microbial diversity and dynamics is crucial to maximize animal production efficiency and mitigate the emission of greenhouse gases from ruminants. This chapter discusses genetic and nongenetic rumen manipulation methods to achieve better rumen microbial fermentation including improvement of fibrolytic activity, inhibition of methanogenesis, prevention of acidosis, and balancing rumen ammonia concentration for optimal microbial protein synthesis.


Author(s):  
Abdalmajeed Khalid Rasheed, Muthanna Ahmed Mohammed Abdalmajeed Khalid Rasheed, Muthanna Ahmed Mohammed

This study was conducted to find out the effect of using different percentages of wild thyme, Thymus serpyllum in the diets of Awassi lambs, and its effect on growth, carcass characteristics, blood traits and some properties of rumen fluid. This experiment was conducted in field of the Department of Animal Production of College of Agriculture and Forestry at University of Mosul. In this experiment, 24 twenty four male Awassi lambs were used, their ages ranged between 5-6 months, lambs were randomly distributed to 4 four treatments and each treatment included 6 six replicates of lambs. The lambs were raised and fed for a period of 90 days From date of (11/11/2020) the beginning of the experiment to date of slaughtering animals for sampling for research purposes on (9/2/2021). And lambs of first treatment (control) were fed on a standard diet only. Free from any additives consisting of barley, wheat bran, wheat straw, soybean meal, limestone and salt, a second treatment was added wild thyme 10 gm/kg feed/head daily, third treatment was 20 gm/kg feed/head daily and fourth treatment was 30 g/kg of feed/head per day. The results of experiment did not show significant differences in daily and total weight gain and carcass characteristics. The results of pH of rumen fluid before feeding or after feeding two hours, nor concentration of rumen liquid ammonia two hours after feeding did not show significant differences between the four treatments. As for the ammonia concentration of the rumen fluid before feeding, it indicated a significant superiority (P≤ 0.05) in treatment. Fourth compared to other transactions. Also, no significant differences were observed in blood characteristics.


Processes ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 2275
Author(s):  
Rubayyi T. Alqahtani ◽  
Abdelhamid Ajbar ◽  
Samir Kumar Bhowmik ◽  
Rabab Ali Alghamdi

The paper investigates the stability and bifurcation phenomena that can occur in membrane reactors for the production of hydrogen by ammonia decomposition. A simplified mixed model of the membrane reactor is studied and two expressions of hydrogen permeation are investigated. The effect of the model design and operating parameters on the existence of steady state multiplicity is discussed. In this regard, it is shown that the adsorption-inhibition effect caused by the competitive adsorption of ammonia can lead to the occurrence of multiple steady states in the model. The steady state multiplicity exists for a wide range of feed ammonia concentration and reactor residence time. The effect of the adsorption constant, the membrane surface area and its permeability on the steady state multiplicity is delineated. The analysis also shows that no Hopf bifurcation can occur in the studied model.


2021 ◽  
Vol 8 ◽  
Author(s):  
Amanda M. Spillane ◽  
Jenica L. Haraschak ◽  
Maureen A. McMichael

A 5-month-old male intact Great Pyrenees was presented for an acute onset of severe neurologic signs (stupor, absent menace, intermittent head turn to the left). The patient's history included possible naproxen ingestion with a maximum ingested dose of 59 mg/kg, exceeding the reported dose of &gt;50 mg/kg known to cause neurologic signs. Blood sampling for baseline bloodwork was performed, and intravenous lipid emulsion (ILE) was subsequently administered, for treatment of the suspected toxicosis. Due to severe and life-threatening neurologic signs, other methods of decontamination were contraindicated and unlikely to be effective; extracorporeal therapy was also unavailable. Complete resolution of neurologic signs occurred 30 min after completion of ILE therapy. At this time, the owners found the missing naproxen tablets after returning home and the bloodwork results returned revealing findings consistent with hepatic encephalopathy. The fasted blood ammonia concentration immediately prior to ILE administration was 702.1 μg/dL (reference interval, RI: 24–36 μg/dL) and decreased to 194.1 μg/dL 24 h later. In the first 24 h, the patient also received three doses of lactulose, N-acetylcysteine, and intravenous fluids. The patient was subsequently diagnosed with a single, large intrahepatic portosystemic shunt via computed tomography and underwent an endovascular coil embolization procedure. Given the rapid and dramatic improvement in severe neurologic signs after ILE therapy alone, it is strongly suspected that this treatment resulted in improvement of hepatic encephalopathy.


Atmosphere ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1607
Author(s):  
Rahul Singh ◽  
Kyunghoon Kim ◽  
Gyutae Park ◽  
Seokwon Kang ◽  
Taehyun Park ◽  
...  

Atmospheric ammonia is a significant pollutant throughout the year, necessitating standardized measurement and identification of emission factors. We performed a quantized evaluation of ammonia concentrations at various locations in and around Seoul, South Korea. The established testing methods of the Radiello Passive Sampler were used for ammonia sampling, and the method was validated using annular denuder sampling. Urban and suburban areas were studied to gain a deeper understanding of the factors responsible for ammonia pollution. This study aimed to establish the fluctuations in concentration over one year, by analyzing the seasonal and regional variation in ammonia concentration. Livestock and agricultural areas recorded the highest concentration of ammonia among all sites, with the highest concentration recorded in autumn. However, at most of the other studied sites, the highest and lowest ammonia concentrations were recorded during summer and winter, respectively. This study attempted to establish a correlation between ammonia concentration and temperature, as well as ammonia concentration and altitude.


Author(s):  
Ikha Rasti Julia Sari ◽  
Januar Arif Fatkhurrahman ◽  
Yose Andriani

Ammonia known as harmful gas that could impact on health and environment. Typically, ammonia gas emitted by fertilizer industry, rubber factory, etc. There are many options for advance industry to control ammonia gas pollution, absorption tower using water scrubber and using activated carbon as adsorption reaction could be an option. But for middle- and lower-class industry, it is common in Indonesia, as seen on many rubber factories, ammonia gas pollution is serious problem to control, actually they have used wet scrubber but eficiency is lower about 47%. This study measure performance for ammonia elimination as gas pollutant using absorption tower and adsorption tower in laboratory scale. Using electrochemical gas sensor, we measure both ammonia concentration for inlet and outlet simultaneously to settle saturation point of these two types of ammonia emission control. In conclusion, Ammonia absorbed in water proportional to saturation time and absorbent volume. Highest absorbed ammonia concentration 1.538 mg/L on 4000 mL absorbent. For Adsorption system, saturation time proportional and correlated to adsorbent weight and Adsorption capacity reverse correlated to adsorbent weight. Optimum adsorption point can be achieved from intersection curve between saturation time and adsorption capacity which is 1200 grams adsorbent


Sign in / Sign up

Export Citation Format

Share Document