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Masao Gen, Dandan Huang, Chak Keung Chan
Reactions between dissolved ammonia and carbonyls, which form light-absorbing species in atmospheric particles, can be accelerated by actively removing water from the reaction system. Here, we examine the effects of relative humidity (RH) on the reactive uptake of glyoxal (Gly) by aqueous particles of ammonium sulfate (AS), ammonium bisulfate, sodium sulfate, magnesium sulfate, ammonium nitrate (AN), and sodium nitrate. In-situ Raman analysis was used to quantify particle-phase Gly and a colored product, 2,2'-biimidazole (BI) as a function of uptake time...
May 18, 2018: Environmental Science & Technology
Wei Jin, Yin Li, Yanfen Cheng, Shengyong Mao, Weiyun Zhu
The cecum plays an important role in the feed fermentation of ruminants. However, information is very limited regarding the cecal microbiota and their methane production. In the present study, the cecal content from twelve local Chinese goats, fed with either a hay diet (0% grain) or a high-grain diet (71.5% grain), were used to investigate the bacterial and archaeal community and their methanogenic potential. Microbial community analysis was determined using high-throughput sequencing of 16S rRNA genes and real-time PCR, and the methanogenesis potential was assessed by in vitro fermentation with ground corn or hay as substrates...
May 17, 2018: Antonie Van Leeuwenhoek
Alexander J Schmithausen, Inga Schiefler, Manfred Trimborn, Katrin Gerlach, Karl-Heinz Südekum, Martin Pries, Wolfgang Büscher
Extensive experimentation on individual animals in respiration chambers has already been carried out to evaluate the potential of dietary changes and opportunities to mitigate CH₄ emissions from ruminants. Although it is difficult to determine the air exchange rate of open barn spaces, measurements at the herd level should provide similarly reliable and robust results. The primary objective of this study was (1) to define a validity range (data classification criteria (DCC)) for the variables of wind velocity and wind direction during long-term measurements at barn level; and (2) to apply this validity range to a feeding trial in a naturally cross-flow ventilated dairy barn...
May 16, 2018: Animals: An Open Access Journal From MDPI
Lee M Margolis, Lisa Ceglia, Donato A Rivas, Bess Dawson-Hughes, Roger A Fielding
With aging there is a chronic low-grade metabolic-acidosis that may exacerbate negative protein balance during weight loss. The objective of this randomized pilot study was to assess the impact of 90 mmol∙day-1 potassium bicarbonate (KHCO₃) versus a placebo (PLA) on 24-h urinary net acid excretion (NAE), nitrogen balance (NBAL), and whole-body ammonia and urea turnover following short-term diet-induced weight loss. Sixteen (KHCO₃; n = 8, PLA; n = 8) older (64 ± 4 years) overweight (BMI: 28.5 ± 2.1 kg∙day-1 ) men completed a 35-day controlled feeding study, with a 7-day weight-maintenance phase followed by a 28-day 30% energy-restriction phase...
May 16, 2018: Nutrients
J Philipp Wagner, David C McDonald Ii, Michael A Duncan
Protonated ethylenediamine monomer, dimer and trimer were produced in the gas phase by an electrical discharge/supersonic expansion of argon seeded with ethylenediamine (C2H8N2, en) vapor. Infrared spectra of these ions were measured in the region from 1000 to 4000 cm-1 using laser photodissociation and argon tagging. Computations at the CBS-QB3 level were performed to explore possible isomers and understand the infrared spectra. The protonated monomer exhibits a gauche conformation and an intramolecular hydrogen bond...
May 17, 2018: Journal of Physical Chemistry. A
Jason M Montgomery, David A Mazziotti
FeMoco, MoFe7 S9 C, has been shown to be the active catalytic site for the reduction of nitrogen to ammonia in the nitrogenase protein. An understanding of its electronic structure including strong electron correlation is key to designing mimic catalysts capable of ambient nitrogen fixation. Active spaces ranging from [54, 54] to [65, 57] have been predicted for a quantitative description of FeMoco's electronic structure. However, a wave function approach for a singlet state using a [54, 54] active space would require 1029 variables...
May 17, 2018: Journal of Physical Chemistry. A
Zitong Liu, Guanxin Zhang, Deqing Zhang
Organic semiconductors have received increasing attentions in recent years because of their promising applications in various optoelectronic devices. The key performance metric for organic semiconductors is charge carrier mobility, which is governed by the electronic structures of conjugated backbones and intermolecular/interchain π-π interactions and packing in both microscopic and macroscopic levels. For this reason, more efforts have been paid to the design and synthesis of conjugated frameworks for organic semiconductors with high charge mobilities...
May 17, 2018: Accounts of Chemical Research
Luz Alejo, John Atkinson, Víctor Guzmán-Fierro, Marlene Roeckel
Computational self-adapting methods (Support Vector Machines, SVM) are compared with an analytical method in effluent composition prediction of a two-stage anaerobic digestion (AD) process. Experimental data for the AD of poultry manure were used. The analytical method considers the protein as the only source of ammonia production in AD after degradation. Total ammonia nitrogen (TAN), total solids (TS), chemical oxygen demand (COD), and total volatile solids (TVS) were measured in the influent and effluent of the process...
May 16, 2018: Environmental Science and Pollution Research International
Ivana Matanovic, Fernando H Garzon
We report herein a density functional theory study of the nitrogen electroreduction and hydrogen evolution reactions on cubic molybdenum carbide (MoC) in order to investigate the viability of using this material as an electro-catalyst for ammonia synthesis. Free energy diagrams for associative and dissociative Heyrovsky mechanisms showed that nitrogen reduction on cubic MoC(111) can proceed via an associative mechanism and that small negative potentials of -0.3 V vs. standard hydrogen electrode can onset the reduction of nitrogen to ammonia...
May 17, 2018: Physical Chemistry Chemical Physics: PCCP
Dohyup Kim, Bushra F Minhas, Hongmei Li-Byarlay, Allison K Hansen
Microbes are known to influence insect-plant interactions; however, it is unclear if host-plant diet influences the regulation of nutritional insect symbioses. The pea aphid, Acyrthosiphon pisum , requires its nutritional endosymbiont, Buchnera , for the production of essential amino acids. We hypothesize that key aphid genes that regulate the nutritional symbioses respond to host-plant diet when aphids feed on a specialized (alfalfa) compared to a universal host-plant diet (fava), which vary in amino acid profiles...
May 16, 2018: G3: Genes—Genomes—Genetics
Shaine Mehta, Sarrah Tayabali, Robin Lachmann
BACKGROUND: Sodium valproate is a commonly used anticonvulsant. It is widely recognized that valproate can cause hyperammonemia, particularly in people with underlying liver disease. Patients with urea cycle disorders are genetically predisposed to this adverse event and can develop severe hyperammonemia if given valproate. This can occur even if liver functions tests and plasma concentration of valproate are normal, highlighting the importance of checking ammonia levels in any patient presenting with encephalopathy...
May 17, 2018: Journal of Medical Case Reports
Yusuke Naraki, Ko Ariga, Hideyuki Oka, Hirokazu Kurashige, Tsuneji Sano
An isomorphously substituted Al-free Fe-BEA zeolite with extremely high Fe content (~7 wt.%) was synthesized by a facile and industrially friendly method using an excess amount of NaOH. The obtained Fe-BEA zeolite was highly crystalline and showed a well-facetted bipyramidal morphology, similarly to beta zeolites synthesized in a fluoride medium. The chemical states of Fe in the above zeolite were investigated by diffuse reflectance ultraviolet-visible (UV-Vis) absorption spectroscopy, electron paramagnetic resonance (EPR) spectroscopy, and X-ray absorption fine structure (XAFS) spectroscopy...
January 1, 2018: Journal of Nanoscience and Nanotechnology
Xin Xie, Jingjun Liu, Tuanfeng Li, Ye Song, Feng Wang
Note that 3d transition metal and nitrogen co-doped carbon materials (TM-N-C) are considered as the most promising next-generation electrocatalysts alternative to precious Pt for oxygen reduction reaction (ORR). Herein, we have fabricated a Cu-N-C catalyst through directly grafting copper-nitrogen complexes composed by cuprous chloride and ammonia water onto the surface of an industrial carbon black at 500℃. In an alkaline environment, the synthesized catalyst exhibits excellent ORR catalytic activity, which is comparable to the state-of-the-art Pt/C catalyst but far exceeding that obtained by the original carbon...
May 16, 2018: Chemistry: a European Journal
Moiz Bakhiet, Aminah M I AlAwadi, Maryam M AlHammadi, Maryam F Ali, Noora Butti
INTRODUCTION: Arginine is an essential amino acid that plays an important role in various body functions including cell division, wound healing, removal of ammonia, immune function, and release of hormones. Hyperargininemia, an autosomal recessive genetic disorder, is considered one of the least common urea cycle disorders. It rarely presents in the neonatal period but rather appears in children at the age between 2 and 4 years. CASE PRESENTATION: Herein, we demonstrate a case of a 14-year-old female who presented to the neurology clinic with several neurological complications, which were found to be a consequence of high levels of arginine discovered after performing a metabolic screening test...
May 2018: Medicine (Baltimore)
Tirta Rona Mayangsari, Jae-Min Park, Luchana Lamierza Yusup, Jiyeon Gu, Jin-Hyuk Yoo, Heon-Do Kim, Won-Jun Lee
We report the catalyzed atomic layer deposition (ALD) of silicon oxide using Si2 Cl6 , H2 O, and various alkylamines. The density functional theory (DFT) calculations using periodic slab model of the SiO2 surface were performed for the selection of alternative Lewis-base catalysts with high catalytic activities. During the first half-reaction, the catalysts with less steric hindrance such as pyridine would be more effective than bulky alkylamines despite lower nucleophilicity. On the other hand, during the second half-reaction, the catalysts with a high nucleophilicity such as triethylamine (Et3 N) would be more efficient because the steric hindrance is less critical...
May 16, 2018: Langmuir: the ACS Journal of Surfaces and Colloids
Xiangyu He, Weiwei Sun, Ting Ge, Chunlong Mu, Weiyun Zhu
High-protein diet could cause an increase in protein fermentation in the large intestine, leading to an increased production of potentially detrimental metabolites. We hypothesized that an increase in corn resistant starch content may attenuate the protein fermentation. The aim of this study was to evaluate the effect of resistant starch on protein fermentation by inocula from large intestine of pigs using in vitro cultivation. Fermentation patterns were analyzed during a 24-h incubation of cecal and colonic digesta with varying corn resistant starch contents, using casein protein as sole nitrogen source...
September 2017: Animal nutrition
Elham Karimizadeh, Morteza Chaji, Tahereh Mohammadabadi
This study was conducted to compare effects of 3 physical forms of feed including mash (diet 1), pellet (diet 2) and complete feed block (CFB; diet 3) on digestion, fermentation and performance of lambs. Twenty-one lambs with an initial average body weight of 26 ± 2.5 kg and 6 ± 1.5 months of age were assigned through a completely randomized design to 3 treatments and 7 replicates. The experimental treatments had the same formulation. The results of present experiment showed that CFB significantly increased feed intake and nutrient digestibility ( P  < 0...
June 2017: Animal nutrition
Yoshiaki Sato, Wanna Angthong, Patima Butcha, Motoharu Takeda, Kazato Oishi, Hiroyuki Hirooka, Hajime Kumagai
Four Thai native cattle were used in a 4 × 4 Latin square design experiment to evaluate the availability of desalted mother liquor (DML) as replacement of salt in concentrate. Each cattle was assigned to one of the following concentrate feeding treatments: C1, 1% NaCl was added as salt; C2, 2% NaCl was added as salt; D1, 1% NaCl was replaced by DML; D2, 2% NaCl was replaced by DML, on a dry matter (DM) basis. The animals were fed rice straw and experimental concentrates (40:60) at 1.9% of body weight on a DM basis, daily...
May 16, 2018: Animal Science Journal, Nihon Chikusan Gakkaihō
Bin Xie, Yong-Wen Ma, Jin-Quan Wan, Yan Wang, Zhi-Cheng Yan, Lin Liu, Ze-Yu Guan
Anaerobic ammonium oxidation (ANAMMOX) has been regarded as an efficient process to treat nitrogen-containing wastewater. However, the treatment process is not fully understood in terms of reaction mechanisms, process simulation, and control. In this paper, a multi-objective control strategy mixed soft-sensing model (MCSSM) is developed to systematically design the operating variations for multi-objective control by integrating the developed model, a least square support vector machine optimized with principal component analysis (PCA-LSSVM) and non-dominated sorting genetic algorithm-II (NSGA-II)...
May 15, 2018: Environmental Science and Pollution Research International
Mengmeng Shao, Yangfan Shao, Wenzhou Chen, Kin Long Ao, Rui Tong, Qing Zhu, Iat Neng Chan, Weng Fai Ip, Xingqiang Shi, Hui Pan
Active catalysts for nitrogen fixation (N2-fixation) have been widely pursued through constant efforts for industrial applications. Here, we report a family of catalysts, MXenes (M2X: M = Mo, Ta, Ti, and W; X = C and N), for application in N2-fixation based on density functional theory calculations. We find that the catalytic performance of MXenes strongly depends on the reaction energy in each reaction step. More exothermic steps lead to higher catalytic performance in the course of N2-fixation. We show that the reaction energy in N2-fixation is strongly affected by the charge transfer: (1) if N atoms gain more electrons in a step, the reaction is exothermic with a larger reaction energy; (2) if N atoms lose electrons in a step, the reaction is endothermic in general...
May 16, 2018: Physical Chemistry Chemical Physics: PCCP
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