The current knowledge of Mercury’s orbit has mainly been gained by direct radar ranging obtained from the 60s to 1998 and by five Mercury flybys made with Mariner 10 in the 70s, and with MESSENGER ...made in 2008 and 2009. On March 18, 2011, MESSENGER became the first spacecraft to orbit Mercury. The radioscience observations acquired during the orbital phase of MESSENGER drastically improved our knowledge of the orbit of Mercury. An accurate MESSENGER orbit is obtained by fitting one-and-half years of tracking data using GINS orbit determination software. The systematic error in the Earth-Mercury geometric positions, also called range bias, obtained from GINS are then used to fit the INPOP dynamical modeling of the planet motions. An improved ephemeris of the planets is then obtained, INPOP13a, and used to perform general relativity tests of the parametrized post-Newtonian (PPN) formalism. Our estimations of PPN parameters (γ and β) are more stringent than previous results.
Water quality parameters like temperature, pH, total dissolved solids (TDS), total suspended solids (TSS), dissolved oxygen (DO), oil and grease, etc., are calculated from the field while parameters ...like biological oxygen demand (BOD) and chemical oxygen demand (COD) are interpreted through the laboratory tests. On one hand parameters like temperature, pH, DO, etc., can be accurately measured with the exceeding simplicity, whereas on the other hand calculation of BOD and COD is not only cumbersome but also inaccurate many times. A number of previous researchers have tried to use different empirical methods to predict BOD and COD but these empirical methods have their limitations due to their less versatile application. In this paper, an attempt has been made to calculate BOD and COD from simple field parameters like temperature, pH, DO, TSS, etc., using Artificial Neural Network (ANN) method. Datasets have been obtained from analysis of mine water discharge of one of the mines in Jharia coalfield, Jharkhand, India. 73 data sets were used to establish ANN architecture out of which 58 datasets were used to train the network while 15 datasets for testing the network. The results show encouraging similarity between experimental and predicted values. The RMSE values obtained for the BOD and COD are 0.114 and 0.983 %, respectively.
Biofloc is a conglomeric aggregation of microbial communities such as phytoplankton, bacteria, and living and dead particulate organic matter. Biofloc technology involves manipulation of C/N ratio to ...convert toxic nitrogenous wastes into the useful microbial protein and helps in improving water quality under a zero water exchange system. It may act as a complete source of nutrition for aquatic organisms, along with some bioactive compounds that will enhance growth, survival, and defense mechanisms, and acts as a novel approach for health management in aquaculture by stimulating innate immune system of animals. Nutritionally, the floc biomass provides a complete source of nutrition as well as various bioactive compounds that are useful for improving the overall welfare indicators of aquatic organisms. Beneficial microbial bacterial floc and its derivative compounds such as organic acids, polyhydroxy acetate and polyhydroxy butyrate, could resist the growth of other pathogens, thus serves as a natural probiotic and immunostimulant. The technology is useful in maintaining optimum water quality parameters under a zero water exchange system, thus prevents eutrophication and effluent discharge into the surrounding environment. Moreover, the technology will be useful to ensure biosecurity, as there is no water exchange except sludge removal. The technology is economically viable, environmentally sustainable, and socially acceptable.
Antibiotics, often supplemented in feed, used as a growth promoter, may cause their residual effect in animal produce and also trigger antibiotic resistance in bacteria, which is of serious concern ...among swine farming entrepreneurs. As an alternative, supplementing probiotics gained interest in recent years. Lactobacillus being the most commonly used probiotic agent improves growth performance, feed conversion efficiency, nutrient utilization, intestinal microbiota, gut health and regulates immune system in pigs. The characteristics of Lactobacillus spp. and their probiotic effects in swine production are reviewed here under.
We use the Herschel/PACS spectrometer to study the global and spatially resolved far-infrared (FIR) fine-structure line emission in a sample of 52 galaxies that constitute the SHINING survey. These ...galaxies include star-forming, active-galactic nuclei (AGNs), and luminous infrared galaxies (LIRGs). We find an increasing number of galaxies (and kiloparsec-size regions within galaxies) with low line-to-FIR continuum ratios as a function of increasing FIR luminosity (LFIR), dust infrared color, LFIR to molecular gas mass ratio (LFIR/Mmol), and FIR surface brightness ( FIR). The correlations between the C ii/FIR or O i/FIR ratios with FIR are remarkably tight (∼0.3 dex scatter over almost four orders of magnitude in FIR). We observe that galaxies with and FIR 1011 L kpc−2 tend to have weak fine-structure line-to-FIR continuum ratios, and that LIRGs with infrared sizes 1 kpc have line-to-FIR ratios comparable to those observed in typical star-forming galaxies. We analyze the physical mechanisms driving these trends in Paper II. The combined analysis of the C ii, N ii 122 m, and O iii 88 m lines reveals that the fraction of the C ii line emission that arises from neutral gas increases from 60% to 90% in the most active star-forming regions and that the emission originating in the ionized gas is associated with low-ionization, diffuse gas rather than with dense gas in H ii regions. Finally, we report the global and spatially resolved line fluxes of the SHINING galaxies to enable the comparison and planning of future local and high-z studies.
Operando X‐ray absorption experiments and density functional theory (DFT) calculations are reported that elucidate the role of copper redox chemistry in the selective catalytic reduction (SCR) of NO ...over Cu‐exchanged SSZ‐13. Catalysts prepared to contain only isolated, exchanged CuII ions evidence both CuII and CuI ions under standard SCR conditions at 473 K. Reactant cutoff experiments show that NO and NH3 together are necessary for CuII reduction to CuI. DFT calculations show that NO‐assisted NH3 dissociation is both energetically favorable and accounts for the observed CuII reduction. The calculations predict in situ generation of Brønsted sites proximal to CuI upon reduction, which we quantify in separate titration experiments. Both NO and O2 are necessary for oxidation of CuI to CuII, which DFT suggests to occur by a NO2 intermediate. Reaction of Cu‐bound NO2 with proximal NH4+ completes the catalytic cycle. N2 is produced in both reduction and oxidation half‐cycles.
Copper redox catalysis: Operando spectroscopy and density functional calculations isolate copper oxidation and reduction half‐cycles during the selective reduction of NOx over a Cu‐exchanged SSZ‐13 zeolite catalyst containing only isolated CuII sites. NH3 and NO together reduce CuII to CuI ions, and each reduction event generates a CuI/H+ pair (see picture).
Biofloc technology (BFT) is an aquaculture technology that uses microbial communities to produce a balanced aquatic environment for fish and crustaceans. This study evaluated the global research ...trends and measured the performance of researchers, organizations or research centers, countries, and funding agencies participating in BFT research in the last decade. Scientific knowledge mapping was also performed to understand the social and conceptual structure of the research publications. The study was conducted based on journal article publications indexed in the Scopus database between 2013 and 2022. The analysis showed that BFT research was increasing steadily, with a total of 911 documents published in the past 10 years. Brazil, China, and India were the three most productive countries in the field. The most productive journals were Aquaculture, Aquaculture Research, and Aquaculture International. Regarding research topics, the largest share of documents was related to bioflocs and their technologies, followed by
Litopenaeus vannamei
, water quality, growth performance, shrimp, Nile tilapia,
Oreochromis niloticus
, etc. Co-authorship network analysis revealed that the largest cluster comprised researchers from Brazil, China, and India. Moreover, the study of societal attention revealed that the BFT research needs more public attention as the research was discussed and mentioned only a few social media platforms. However, the BFT research had significant readers on Mendeley. This study provides a comprehensive overview of the current state of BFT research and the research performance of scientific actors. It can serve as a valuable reference for researchers and policymakers.
Pyrolysis products, such as aqueous phase of bio-oil, bio-oil, and biochar, prepared from biomass sugarcane leaves, wheat straw, rice husk, and pine needles were evaluated for wheat seed germination. ...It was observed that the seeds exposed to pure bio-oil and aqueous phase of bio-oil had acquired inhibitory growth properties, whereas the seeds treated with biochar showed enhanced growth characteristics. When comparing wheat biochar to other biochars, the maximum number of roots was observed at 2 mg/mL biochar concentration. Biochemical evaluation of wheat seeds treated with 2 mg/mL wheat biochar revealed higher GA
3
, β-amylase, reducing sugar, and total dehydrogenase activities, while there was a reduction in α-amylase activity and starch in the first 20 h after seed imbibitions. The GC–MS of wheat straw biochar extract detected karrikin-like compounds 2,3-Dihydro-benzofuran, Oxirane (hexadecyloxy) methyl-Propane, and beta-sitosterol. Some other compounds supposed of having growth inhibitory activity were also found. In silico analysis revealed that beta-sitosterol present in wheat straw biochar had lower ΔG value with karrikins receptor of
Arabidopsis
may be responsible for enhanced growth of wheat seeds.
Aquaponics is an integrated fish and crop production system that includes aquaculture and hydroponics. The purpose of this study was to assess aquaponic research and social media attention in light ...of the exponential growth of aquaponics systems. This article condenses numerous studies into a single paper, which provides insights into the worldwide growth and advancement of the study field and establishes a future research agenda. A thorough scientometric study of the worldwide scientific output on aquaponics from 2004 to 2021 was conducted using the Scopus database. Altmetric data for individual articles were collected from Altmetric.com. The analysis tools, MS Excel, Tableau, Biblioshiny, and VOSviewer, were used in this study. The results show that aquaponics research has been growing significantly over the years. In recent years, aquaponics research primarily focused on the optimization of system performance (component ratio, hydraulic loading rate, hydroponic component, etc.), wastewater treatment, nutrient management, system production, technology adoption, and varieties of plants and fishes. The study identified the most prolific authors, journals, and affiliations in the field of aquaponics. The USA, Europe, and some Asian countries, especially China and India, are the most innovative regions with significant research in this area. Altmetric analysis found that aquaponics research has not received impressive online social attention and needs further social media promotion. However, publications have a considerable readership on Mendeley.
Variation in the local current density along a polymer electrolyte membrane (PEM) fuel cell often causes sharp temperature and stress gradients that affect the membrane durability and service life of ...fuel cells. Towards minimizing the variation in local current density, and potentially improving fuel cell reliability, this paper explores the use of functionally graded porosity in the gas diffusion electrode layers along the flow direction. A computational model for fuel cell is used together with a numerical optimization method to determine the optimum porosity distribution along the length of the channel, with the objective of maximizing power density while limiting the current density variation. The optimum porosity distribution and the corresponding local current density distribution are compared and discussed in detail for different operating conditions. Experimental studies are conducted to measure the local current density distribution in a fuel cell with a segmented current collector and to evaluate the effects of graded porosity distribution in the gas diffusion layer. It is shown that use of an optimally graded porosity distribution improves the uniformity in current density along the length of the channel by up to a factor of 10, while maximizing the power density.
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