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Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 547
Author(s):  
DaEun Yang ◽  
Kyutae Seo ◽  
Hyo Kang

We synthesized a series of renewable and plant-based isoeugenol-substituted polystyrenes (PIEU#, # = 100, 80, 60, 40, and 20, where # is the molar percent content of isoeugenol moiety), using polymer modification reactions to study their liquid crystal (LC) alignment behavior. In general, the LC cells fabricated using polymer film with a higher molar content of isoeugenol side groups showed vertical LC alignment behavior. This alignment behavior was well related to the surface energy value of the polymer layer. For example, vertical alignments were observed when the polar surface energy value of the polymer was smaller than approximately 3.59 mJ/m2, generated by the nonpolar isoeugenol moiety with long and bulky carbon groups. Good alignment stability at 100 °C and under ultraviolet (UV) irradiation of 15 J/cm2 was observed for the LC cells fabricated using PIEU100 as a LC alignment layer. Therefore, renewable isoeugenol-based materials can be used to produce an eco-friendly vertical LC alignment system.


2021 ◽  
Vol 16 ◽  
pp. 1-7
Author(s):  
J. A. Ibeawuchi ◽  
A. O. Akinsoyinu

Four lactating White Fulani (Zebu) cows fitted with permanent rumen cannular were fed four. diets: (A) Acha hay (Digitaria exilis Stapf, (B) 50% acha hay plus 50% brewers dried grains (BDG), (C) 75% BDG plus 25% hay and (D) 100% BDG in a 4 x 4 latin square design. Analysis of rumen total Volatile Fatty acids (VFAS), individual VFAs, ammonia-N and pH as well as some milk constituents were carried out simultaneously. Mean ruminal pH and total VFA (MM/100ml) were 7.1,6.2; 6.5, 8.0; 5.8,  14.9 and 5.8, 13.1 for A, B, C, and D respectively. The corresponding acetate to propionate (A/P) ratios were 4.97, 4.40, 3.20 and 3.40. The molar percent values of butyrate yielded by A and B were similar and less (P<0.05) than the value for C or D. Ruminal ammonia-N (mg/100ml) ranged from 5.7 for A to 6.8 for D. Total VFA, NH3-N and pH of the rumen fluid were affected by time of feeding (P<0.05). The correlations between ruminal pH and acetate (r = 0.98), pH and total VFA (r = -0.90), and acetate and propionate (r = -0.75) were significanct(P <0.05). Cows on treatment A (acha hay) yielded higher percent milk fat (P<0.05) and lower percent milk protein than those on B, C, or D. Treatment effects on milk pH and percentages of lactose, solids-not-fat (SNF) and ash were not significant. The observed depression in milk fat of cows on treatments B, C and D in comparison with cows on treatment A wasrelated to a decrease in rumen acetate and an increase in propionate. It was observed that the fermentation of BDG yielded acetate within limits required for efficient milk production.


2020 ◽  
Vol 295 (7) ◽  
pp. 2018-2033 ◽  
Author(s):  
Aaron K. Olson ◽  
Bertrand Bouchard ◽  
Wei Zhong Zhu ◽  
John C. Chatham ◽  
Christine Des Rosiers

The hexosamine biosynthesis pathway (HBP) branches from glycolysis and forms UDP-GlcNAc, the moiety for O-linked β-GlcNAc (O-GlcNAc) post-translational modifications. An inability to directly measure HBP flux has hindered our understanding of the factors regulating protein O-GlcNAcylation. Our goals in this study were to (i) validate a LC-MS method that assesses HBP flux as UDP-GlcNAc (13C)-molar percent enrichment (MPE) and concentration and (ii) determine whether glucose availability or workload regulate cardiac HBP flux. For (i), we perfused isolated murine working hearts with [U-13C6]glucosamine (1, 10, 50, or 100 μm), which bypasses the rate-limiting HBP enzyme. We observed a concentration-dependent increase in UDP-GlcNAc levels and MPE, with the latter reaching a plateau of 56.3 ± 2.9%. For (ii), we perfused isolated working hearts with [U-13C6]glucose (5.5 or 25 mm). Glycolytic efflux doubled with 25 mm [U-13C6]glucose; however, the calculated HBP flux was similar among the glucose concentrations at ∼2.5 nmol/g of heart protein/min, representing ∼0.003–0.006% of glycolysis. Reducing cardiac workload in beating and nonbeating Langendorff perfusions had no effect on the calculated HBP flux at ∼2.3 and 2.5 nmol/g of heart protein/min, respectively. To the best of our knowledge, this is the first direct measurement of glucose flux through the HBP in any organ. We anticipate that these methods will enable foundational analyses of the regulation of HBP flux and protein O-GlcNAcylation. Our results suggest that in the healthy ex vivo perfused heart, HBP flux does not respond to acute changes in glucose availability or cardiac workload.


2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Billy N. Cardoso ◽  
Emerson C. Kohlrausch ◽  
Marina T. Laranjo ◽  
Edilson V. Benvenutti ◽  
Naira M. Balzaretti ◽  
...  

TiO2/SiO2 nanoparticles with 3, 5, and 10 molar percent of silica, were synthesized by hydrothermal method and characterized by SEM, TEM, N2 adsorption-desorption isotherms, X-ray diffraction, and Raman and UV-Vis spectroscopy. While pristine TiO2 thermally treated at 500°C presents a surface area of 36 m2 g-1 (±10 m2 g-1), TiO2/SiO2 containing 3, 5, and 10 molar percent of silica present surface areas of 93, 124, and 150 m2 g-1 (±10 m2 g-1), respectively. SiO2 is found to form very small amorphous domains well dispersed in the TiO2 matrix. X-ray diffraction and Raman spectroscopy data show that anatase-to-rutile phase transition temperature is delayed by the presence of SiO2, enabling single-anatase phase photoanodes for DSSCs. According to the I×V measurements, photoanodes with 3% of SiO2 result in improved efficiency, which is mainly related to increased surface area and dye loading. In addition, the results suggest a gain in photocurrent related to the passivation of defects by SiO2.


2015 ◽  
Vol 308 (4) ◽  
pp. E306-E314 ◽  
Author(s):  
Satya S. Houin ◽  
Paul J. Rozance ◽  
Laura D. Brown ◽  
William W. Hay ◽  
Randall B. Wilkening ◽  
...  

Reduced fetal glucose supply, induced experimentally or as a result of placental insufficiency, produces an early activation of fetal glucose production. The mechanisms and substrates used to fuel this increased glucose production rate remain unknown. We hypothesized that in response to hypoglycemia, induced experimentally with maternal insulin infusion, the fetal liver would increase uptake of lactate and amino acids (AA), which would combine with hormonal signals to support hepatic glucose production. To test this hypothesis, metabolic studies were done in six late gestation fetal sheep to measure hepatic glucose and substrate flux before (basal) and after [days (d)1 and 4] the start of hypoglycemia. Maternal and fetal glucose concentrations decreased by 50% on d1 and d4 ( P < 0.05). The liver transitioned from net glucose uptake (basal, 5.1 ± 1.5 μmol/min) to output by d4 (2.8 ± 1.4 μmol/min; P < 0.05 vs. basal). The [U-13C]glucose tracer molar percent excess ratio across the liver decreased over the same period (basal: 0.98 ± 0.01, vs. d4: 0.89 ± 0.01, P < 0.05). Total hepatic AA uptake, but not lactate or pyruvate uptake, increased by threefold on d1 ( P < 0.05) and remained elevated throughout the study. This AA uptake was driven largely by decreased glutamate output and increased glycine uptake. Fetal plasma concentrations of insulin were 50% lower, while cortisol and glucagon concentrations increased 56 and 86% during hypoglycemia ( P < 0.05 for basal vs. d4). Thus increased hepatic AA uptake, rather than pyruvate or lactate uptake, and decreased fetal plasma insulin and increased cortisol and glucagon concentrations occur simultaneously with increased fetal hepatic glucose output in response to fetal hypoglycemia.


2014 ◽  
Vol 804 ◽  
pp. 63-66
Author(s):  
Pei Wu ◽  
Xue Gang Luo ◽  
Xiao Yan Lin ◽  
Ke Li

In this study, room-temperature driven thermocatalyst (Fe/Sr2Bi2O5 powder) with negative temperature coefficient resistor (NTC) characteristics was prepared by conventional solid state method at various temperatures. Fe/Sr2Bi2O5 powder was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy EDS. The results indicate that Fe/Sr2Bi2O5 powder was prepared and the Fe has been doped successfully in Sr2Bi2O5. The thermocatalyst powder obtained a particular and stable crystal style, meanwhile, besides, well distributed size and rough surface were also found in regard to the thermocatalyst above. On the other hand, the thermocatalyst reactions show that Fe/Sr2Bi2O5 powder has highest removal rate of degradation under the 0.75% (molar percent) content of Fe at 750 oC. The total removal rate of degradation arrives at 93.8% after 3h at 50 oC. Hence, Fe/Sr2Bi2O5 powder may be a potential thermocatalyst at room-temperature for wastewater treatment in the future.


Author(s):  
Behzad Mehdikhani ◽  
Gholam Hossein Borhani

The effects of Al2O3 on the crystallization behavior of glass compositions in the Na2O-CaO-SiO2 system were investigated by differential thermal analysis (DTA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Effect of Al2O3 content on the mechanical, density, phase formation and microstructures of Na2O-CaO–P2O5–Al2O3-SiO2 glass ceramics were studied. Thermal parameters of each glass were studied by DTA. The density of the glass ceramic samples was measured by Archimedes’ method. It was found that the glass–ceramic containing 2.0 molar percent Al2O3 had desirable sintering behavior and reached to an acceptable density. Phase investigation and micro structural study were performed by XRD and SEM, respectively.


2013 ◽  
Vol 291-294 ◽  
pp. 249-252
Author(s):  
Ying Liu ◽  
Lu Lin ◽  
Xiao Yu Sui ◽  
Jun Ping Zhuang ◽  
Chun Sheng Pang

Hydrolysis of glucose to produce levulinic acid catalyzed by ZSM-5 loading SO42-/ ZrO2 was studied in this paper. The effects of different factors such as catalyst amount, reaction temperature, reaction time on the yields of levulinic acid and hydroxymethyl furfural were investigated. It was found that the highest yield of levulinic acid was 55.03% (molar percent) under the conditions of catalyst amount 3 g, reaction temperature 180 °C and reaction time 2.5 h. Surface structure of catalyst was analyzed by FT-IR, indicating that crystallinity of catalyst was 0.66.


2012 ◽  
Vol 554-556 ◽  
pp. 1021-1024 ◽  
Author(s):  
Yong Le Liu ◽  
Fa Xiang Wang ◽  
Jian Yu ◽  
Xiang Hong Li ◽  
Jian Hui Wang

Aspergillus niger can produce an acid-stable α-amylase as well as an acid-unstable one, the relation between the structural differences and their acid-resistant capability is of great interest. In this paper, the primary parameters, secondary and tertiary structures of these two types of α-amylases was analyzed and compared, the results shows that they has 67% sequence identity and high homology in secondary and tertiary structure. The acid-stable α-amylase has lower isoelectric point and higher molar percent of acidic amino acid than the acid-unstable one. The four major structural differences of these two types of enzymes is located at residues 132-138, 206-212, 329-335 and 378-382 and formed vary fold pattern.


2012 ◽  
Vol 302 (5) ◽  
pp. H1086-H1093 ◽  
Author(s):  
Aaron K. Olson ◽  
Bertrand Bouchard ◽  
Xue-Han Ning ◽  
Nancy Isern ◽  
Christine Des Rosiers ◽  
...  

Triiodothyronine (T3) supplementation improves clinical outcomes in infants after cardiac surgery using cardiopulmonary bypass by unknown mechanisms. We utilized a translational model of infant cardiopulmonary bypass to test the hypothesis that T3 modulates pyruvate entry into the citric acid cycle (CAC), thereby providing the energy support for improved cardiac function after ischemia-reperfusion (I/R). Neonatal piglets received intracoronary [2-13Carbon(13C)]pyruvate for 40 min (8 mM) during control aerobic conditions (control) or immediately after reperfusion (I/R) from global hypothermic ischemia. A third group (I/R-Tr) received T3 (1.2 μg/kg) during reperfusion. We assessed absolute CAC intermediate levels and flux parameters into the CAC through oxidative pyruvate decarboxylation (PDC) and anaplerotic carboxylation (PC) using [2-13C]pyruvate and isotopomer analysis by gas and liquid chromatography-mass spectrometry and 13C-nuclear magnetic resonance spectroscopy. When compared with I/R, T3 (group I/R-Tr) increased cardiac power and oxygen consumption after I/R while elevating flux of both PDC and PC (∼4-fold). Although neither I/R nor I/R-Tr modified absolute CAC levels, T3 inhibited I/R-induced reductions in their molar percent enrichment. Furthermore, 13C-labeling of CAC intermediates suggests that T3 may decrease entry of unlabeled carbons at the level of oxaloacetate through anaplerosis or exchange reaction with asparate. T3 markedly enhances PC and PDC fluxes, thereby providing potential substrate for elevated cardiac function after reperfusion. This T3-induced increase in pyruvate fluxes occurs with preservation of the CAC intermediate pool. Our labeling data raise the possibility that T3 reduces reliance on amino acids for anaplerosis after reperfusion.


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