Principal Parameters Research Articles

RETRACTED: Interval-based LQR strategy for optimal control of proton exchange membrane fuel cell system with interval uncertainties

Proton exchange membrane fuel cells (PEMFC) are a type of the increasingly developed sustainable energy systems which have been turned into one of the most popular of them in the last decade. The performance of these types of fuel cells is the best among the others; however, they can be better by an authentic control to maintain in the maximum efficiency in the operative points during the current ripples. To do this and also to improve the value of the output voltage, the two-phase interleaved boost converter is utilized. Since boost converter has uncertain parameters and disturbances in their essence, using the ordinary methods for the control of them can ignore some of the principal parameters. In this study, a new technique is utilized for optimal control of the proton exchange membrane fuel cells with interval uncertain parameters. Here, we consider the uncertainties in the converter inherent. Because of considering the uncertainties in the system, controllability of the system is first testified based on interval arithmetic. Then, an extended version of the linear quadratic regulator strategy using interval analysis is employed for achieving a reliable and optimal solution. Chebyshev inclusion method is utilized for solving the Pontryagins problem of the LQR problem. Eventually, by solving the interval version of the Riccati equations, the robust range for optimal control of the PEMFC is obtained. The results of the proposed system are finally compared with Monte Carlo method for showing the efficiency of the presented technique.

Biomagnification of methylmercury in a marine food web in Laizhou Bay (North China) and associated potential risks to public health

The concentrations of total mercury (THg) and methylmercury (MeHg) were assessed in water, sediment and biota (54 species) samples from the coast of Laizhou Bay, to evaluate MeHg biomagnification in Laizhou Bay food web. The trophic web structure was determined with stable isotope ratios. The MeHg concentrations were highly variable among species ranged from 4.8 ng g−1 in primary producers to 411.2 ng g−1 in spotted sea bass. Weight and ecotype were the principal parameters related to the mercury concentrations for most species. The trophic magnification factors (TMFs) for MeHg and THg were 2.09 and 1.69, respectively, indicating that mercury biomagnification is occurring in this marine food web. The estimated weekly intake (EWI) and target hazard quotient (THQ) values demonstrated that consuming predatory fishes from the bay could cause potential health risks to humans.

New General Maximum Entropy Model for Flow Through Porous Media

New experimental and numerical techniques constitute the major recent advancements in the study of flow through porous media. However, a model that duly links the micro- and macroscales of this phenomenon is still lacking. Therefore, the present work describes a new, analytical model suitable for both Darcian and post-Darcian flow. Unlike its predecessors, most of which are based on empirical assessments or on some derivation of the Navier–Stokes equations, the presented model employed the principle of maximum entropy, along with a reduced number of premises. Nevertheless, it is compatible with classic expressions, such as Darcy’s and Forchheimer’s laws. Also, great adherence to previously published experimental results was observed. Moreover, the developed model allows for the delimitation of Darcian and post-Darcian regimes. It enabled the determination of a probabilistic distribution function of flow velocities within the pore space. Further, it bestowed richer interpretations of the physical meanings of principal flow parameters. Finally, through a new quantity called the entropy parameter, the proposed model may serve as a bridge between experimental and numerical findings both at the micro- and macroscales. Therefore, the present research yielded an analytical, entropy-based model for flow through porous media that is sufficiently general and robust to be applied in several fields of knowledge.

Fabrication of the alginate-combusted coal gangue composite for simultaneous and effective adsorption of Zn(II) and Mn(II)

A combusted coal gangue is an inorganic waste utilized for removal of heavy metal from aqueous mixtures; however, the individual adsorption capacity of this adsorbent is not high individually. Therefore, a natural polysaccharide such as alginate is utilized to make bio- inorganic composite to increase the heavy metals’ adsorption capacity. In this study, the alginate-combusted coal gangue (ACCG) composite was prepared and used as an adsorbent for Zn(II) and Mn(II) removal in batch experiments. The mineralogy, structure, and morphology of the ACCG composite were characterized. The principal parameters have been optimized, which in optimum condition, the maximum uptake of zinc and manganese was obtained 77.68 and 64.29 mg/g, respectively. To catch the mechanism of zinc and manganese adsorption, the equilibrium studies were investigated using nonlinear isotherm models in single and binary systems. The studies indicate that the adsorption process in both systems was carried out in a homogeneous and single layer surface. The amount of Zn(II) and Mn(II) adsorbed in competitive conditions were 65.4 and 53.8 mg/g, respectively. Kinetic studies indicate that intra-particle diffusion is the rate-limiting step of the adsorption process. Furthermore, thermodynamic studies demonstrated that the adsorption of zinc and manganese onto the ACCG composite was spontaneous.

Label-Free Proteomics of the Fetal Pancreas Identifies Deficits in the Peroxisome in Rats with Intrauterine Growth Restriction.

Aim The objective of the present study was to identify differentially expressed proteins (DEPs) in the pancreas of a fetus with intrauterine growth restriction (IUGR) and to investigate the molecular mechanisms leading to adulthood diabetes in IUGR. Methods The IUGR rat model was induced by maternal protein malnutrition. The fetal pancreas was collected at embryonic day 20 (E20). Protein was extracted, pooled, and subjected to label-free quantitative proteomic analysis. Bioinformatics analysis (GO and IPA) was performed to define the pathways and networks associated with DEPs. LC-MS results were confirmed by western blotting and/or quantitative PCR (q-PCR). The principal parameters of oxidative stress-superoxide dismutase (Sod) were determined in blood samples of fetal rats. Results A total of 57 DEPs (27 upregulated, 30 downregulated) were identified with a 1.5-fold change threshold and a p value ≤ 0.05 between the IUGR and the control pancreas. Bioinformatics analysis revealed that these proteins play important roles in peroxisome biogenesis and fission, fatty acid beta-oxidation (FAO), mitotic cell cycle, and histone modification. The peroxin Pex14 was downregulated in the IUGR pancreas as confirmed by western blotting and q-PCR. Pmp70, a peroxisomal membrane protein involved in the transport of fatty acids, was upregulated. Hsd17b4 and Acox1/2, which catalyze different steps of peroxisomal FAO, were dysregulated. Sod plasma concentrations in the IUGR fetus were higher than those in the control, suggesting partial compensation for oxidative stress. Multiple DEPs were related to the regulation of the cell cycle, including reduced Cdk1, Mcm2, and Brd4. The histone acetylation regulators Hdac1/2 were downregulated, whereas Sirt1/3 and acetylated H3K56 were increased in the IUGR fetal pancreas. Conclusion The present study identified DEPs in the fetal pancreas of IUGR rats by proteomic analysis. Downregulation of pancreas peroxins and dysregulation of enzymes involved in peroxisomal FAO may impair the biogenesis and function of the peroxisome and may underlie the development of T2 diabetes mellitus in adult IUGR rats. Disorders of cell cycle regulators may induce cell division arrest and lead to smaller islets. The present data provide new insight into the role of the peroxisome in the development of the pancreas and may be valuable in furthering our understanding of the pathogenesis of IUGR-induced diabetes.

Velocity of a large bubble rising in a stagnant liquid inside an inclined rectangular channel

The velocity of large air bubbles rising in an inclined rectangular channel filled up with stagnant water is investigated within the inertial flow regime. The experiments based on bubble observation by means of a high-speed camera are carried-out in a versatile channel with easily adaptable geometry over a wide range of inclination angles. The results obtained in vertical channels of various aspect ratios are confronted with the previous analytical predictions to confirm bubble velocity scaling based on the channel perimeter. The extrapolation of velocity measurements done at very low inclinations then provides the translation velocities of large bubbles corresponding to horizontal channel placements. These velocities agree well with the results of previous channel emptying experiments and suggest velocity scaling based on the channel height. Markedly different dependences of the bubble rise velocity on the channel inclination are observed in flat and tall channels. The analysis of our experimental data provides a simple model for the prediction of the bubble rise velocity in inclined rectangular channels. The effects of leveling and buoyancy, which are jointly acting on bubbles in inclined channels, are incorporated into the model through two principal parameters: the limiting bubble velocities achieved at the horizontal and vertical channel placement. Considering the inertial regime of large Taylor bubbles, these limiting velocities are predictable with a sufficient accuracy.

Optimization of marine vessels on the basis of tests on model series

The towing-tank resistance data for 20 series of ship models have been collated and processed in a unified manner. These data are presented here in a summarized manner showing the influence of the principal geometric parameters. The most significant parameter is the slenderness ratio which generally should be as large as possible in order to minimize the total resistance at full scale. It is demonstrated that the well-known DTMB Series 64 hulls possess the most promising geometry for the purpose of resistance minimization. It is further shown that the displacement of the prototype plays only a minor role. Thus, the general conclusions apply to any practical size of ship.

In-vivo imaging of methionine metabolism in patients with suspected malignant pleural mesothelioma

In-vivo characterization of malignant pleural mesothelioma (MPM) with C-methionine PET/computed tomography (MET PET). Between September 2014 and February 2016, 30 consecutive patients with clinical suspicion of MPM were prospectively recruited. The study was approved and registered at www.clinicaltrials.gov (NCT02519049). Patients were evaluated at baseline with MET PET (experimental) and fluorine-18 fluorodeoxyglucose PET/computed tomography (FDG PET) (standard). Principal parameters analyzed were SUVmax, SUVmean, metabolic tumor volume (MTV), and metabolic tumor burden (MTB = MTV ×SUVmean). The reference standard for diagnostic performance was based on histology. The presence of malignancy was confirmed in 29/30 patients: 23 (76.6%) with MPM (20 epithelioid, two biphasic, and one sarcomatoid), five (16.6%) with adenocarcinoma of the lung, and one (3.3%) with an undifferentiated carcinoma. In one case, diagnosis was benign pleural inflammation. All tumors showed increased uptake of C-methionine: median SUVmax, SUVmean, MTV, and MTB were, respectively, 5.70 [95% confidence interval (CI): 4.51-6.79], 3.15 (95% CI: 2.71-3.40), 33.85 (95% CI: 14.08-66.64), and 105.25 (95% CI: 41.77-215.25). Pathology data revealed MTV and MTB to be significantly higher in nonepithelioid histology (P < 0.05). The other parameters showed a homogeneous distribution across the tumor types. Overall, MET PET identified 49 lymph nodes, compared with 34 nodes on FDG PET, demonstrating a sensitivity of 91% (95% CI: 80-96%), a positive predictive value of 92% (95% CI: 82- 97%), and an accuracy of 85% (P = 0.0042). MET PET is able to characterize MPM lesions regardless of histology. This technique shows higher sensitivity than FDG PET for the identification of secondary lymph nodes.

Performance of geosynthetic-encased stone column-improved soft clay under vertical cyclic loading

This paper presents the results of a laboratory investigation into the performance of geosynthetic-encased stone column-improved (GESC-improved) soft clay under vertical cyclic loading. A reduced-scale model is adopted to perform a series of tests considering the principal parameters, such as the cyclic loading characteristics, including the loading frequency and amplitude, and the encasement length. The results indicate that, among other things, the overall benefit of the geosynthetic encasement of stone columns installed in soft clay is greater under cyclic loading than under static loading, and that the cyclic effect tends to lead to a stress concentration ratio that is smaller than that under static loading. The effectiveness of this encasement in improving the performance of GESCs becomes greater when subjected to cyclic loading with a lower loading frequency and/or a smaller amplitude. The settlement and pore pressure variations with the encasement length, together with the exhumed GESCs taken after the tests, suggest that full encasement is necessary to maximize the performance of GESCs under cyclic loading.

Relationships between the anisotropy parameters for transversely isotropic mudrocks

Studying the empirical relations between seismic anisotropy parameters is important for the simplification and practical applications of seismic anisotropy. The elastic properties of mudrocks are often described by transverse isotropy. Knowing the elastic properties in the vertical and horizontal directions, a sole oblique anisotropy parameter determines the pattern of variation of the elastic properties of a transversely isotropic (TI) medium in all of the other directions. The oblique seismic anisotropy parameter [Formula: see text], which determines seismic reflection moveout behavior, is important in anisotropic seismic data processing and interpretation. Compared to the other anisotropy parameters, the oblique anisotropy parameter is more sensitive to the measurement error. Although, theoretically, only one oblique velocity is needed to determine the oblique anisotropy parameter, the uncertainty can be greatly reduced if multiple oblique velocities in different directions are measured. If a mudrock is not a perfect TI medium but it is expediently treated as one, then multiple oblique velocity measurements in different directions should lead to a more representative approximation of [Formula: see text] or [Formula: see text] because the directional bias can be reduced. Based on a data quality analysis of the laboratory seismic anisotropy measurement data from the literature, we found that there are strong correlations between the oblique anisotropy parameter and the principal anisotropy parameters when data points of more uncertainty are excluded. Examples of potential applications of these empirical relations are discussed.

Correction to: The volume-based properties for dimensional analysis of micro heat exchanger

In the original publication of the article, under the heading, “Dimensional analysis of volumetric Properties” the dimensions of five principal parameters were incompletely published.

Postoperative discomfort after implant placement according to the All-on-4 concept with or without Zygoma implants: A prospective clinical study.

The purpose of the study was to assess patients' postoperative discomfort after implantations according to the All-on-4 concept with and without using Zygoma implants. Three treatment groups were formed for this prospective study: All-on-4 rehabilitation in the maxilla (group 1, N=25), All-on-4 rehabilitation in the maxilla using at least two Zygoma implants (group 2, N=25), and All-on-4 rehabilitation in the mandible (group 3, N=20). Principal outcome parameters were postoperative pain (100mm VAS) and perceived swelling (100mm VAS). Also, the use of analgesics was documented. The worst postoperative pain of 21.3 (SD 18.9) VAS was observed in group 2, but there was no statistically significant difference between the groups (mixed ANOVA p=.791). The postoperative total intake of painkillers was significantly higher in group 2 than in the other groups (p<.001). On postoperative day 28, the mean pain scores in all groups declined to values below 5 VAS. Postoperative perceived swelling in group 2 was significantly more severe than it was in group 1 and 3 (p<.001). The use of Zygoma implants in All-on-4 surgical interventions had an essential effect on postoperative swelling, but less so on postoperative pain. The slightly increased, but statistically not significantly different postoperative pain in group 2 was compensated by an overall higher postoperative intake of painkillers compared to the other groups.

Reproduction and recruitment of the brown shrimp Crangon crangon in the inner German Bight (North Sea): An interannual study and critical reappraisal

AbstractThe brown shrimp, Crangon crangon, is the most important target of the coastal crustacean fisheries in the German Bight. In order to evaluate the relation between the abundance of ovigerous females and larvae in spring and the recruitment success in autumn, we first analysed the seasonal appearance of ovigerous females and larvae from weekly samples throughout 2012. The spawning season in the German Bight extends over several months comprising multiple unsynchronized spawning events. The minimum shares of ovigerous females appeared in early autumn, and the highest shares in late winter bearing mostly early egg stages. We defined the putative start of the reproductive cycle for November when the frequency of ovigerous females started to increase. There was no distinct separation between winter and summer eggs, but a continuous transition between large eggs spawned in winter (the early spawning season) and batches of smaller eggs in spring and summer. Larval densities peaked in April/May. Consequently, regular annual larval surveys from 2013 to 2016 were scheduled for April/May and extended to six transects covering the inner German Bight. Ovigerous females were most abundant in shallow waters above the 20‐m isobaths, which also explained regional differences in abundance between the regions off North Frisia and East Frisia. No relation was obvious between the number of larvae in spring and recruited stock in autumn. Due to the short lifespan of C. crangon, the combination of various abiotic factors and predator presence seems to be the principal parameters controlling stock size.

Evaluation of cytochrome P450 3A4‑mediated drug‑drug interaction potential between P2Y12 inhibitors and statins.

Ticagrelor and prasugrel are widely used in the treatment of acute coronary syndrome. The co‑administration of ticagrelor or prasugrel with statins in the clinic has already drawn a great deal of attention. The aims of the present study were to evaluate the safety and effectiveness, and guide the rational clinical use of, co‑administration of ticagrelor or prasugrel with statins by exploring potential drug interactions. The activity of cytochrome P450 family 3 subfamily A member 4 (CYP3A4) was detected, and its protein and mRNA expression levels were measured in a rat model and liver microsomes to evaluate the effect of the drug combinations on CYP3A4. High performance liquid chromatography, western blotting and reverse transcription‑quantitative PCR were used to perform these investigations. The invitro experiments suggested that ticagrelor inhibited CYP3A4 activity, with IC50 and inhibitor constant (Ki) values of 68.74 and 26.47µM, respectively; prasugrel also inhibited CYP3A4, activity with IC50 and Ki values of 16.24 and 10.84µM, respectively. When different dosages of the antagonists were combined with simvastatin or atorvastatin, the metabolic rate was reduced more effectively at higher dosages when compared with lower dosages. An invivo pharmacokinetic study demonstrated that the co‑administration of ticagrelor or prasugrel with simvastatin caused an increase in the principal pharmacokinetic parameters of the probe drug dapsone [area under the concentration/time curve (AUC)0‑t, AUC0‑∞ and t1/2] and a decrease in clearance compared with ticagrelor, prasugrel or simvastatin alone. Additional studies confirmed that the two investigated P2Y12 inhibitors were able to decrease the protein level of CYP3A4 by promoting protein degradation through the proteasomal pathway, and combination with statins such as simvastatin had a synergistic inhibitory effect on CYP3A4 activity. These results demonstrated that the co‑administration of P2Y12 inhibitors with simvastatin could markedly inhibit the activity of CYP3A4, and these findings will further influence the assessment of the clinical effectiveness (reduced or enhanced efficacy) and safety (bleeding and rhabdomyolysis) in the clinic.

Pulse Plating of Ni-W-B Coating and Study of Its Corrosion and Wear Resistance

The aim of the current study is to optimize some of the principal parameters to achieve smooth Ni-W-B alloys with high corrosion resistance and wear properties. The pulse plating method was used for preparing Ni-W-B coatings, and the effects of the pulse duty cycle and applied current density on the electrochemical and mechanical properties of the coatings were evaluated. Field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) and the Vickers microhardness (HV) tester were applied to investigate the morphology, roughness and hardness of the prepared coatings. The composition and phases of coatings were analyzed by energy dispersive spectroscopy (EDS), an inductively coupled plasma-optical emission spectrometer (ICP-OES) and X-ray diffraction (XRD). For exploring the corrosion behavior of the coatings, the open circuit potential (OCP), potentiodynamic polarization (Tafel) and electrochemical impedance spectroscopy (EIS) were used. Wear behavior of coatings was studied with the pin-on-disk method. The coating grain size was increased from 17 up to 29 nm by raising the average current density from 10 to 70 mA/cm2 because of the decreasing boron content. At the pulse duty cycle of 20 pct, the high hardness of 905 HV was displayed at the current density of 10 mA/cm2, which contains the maximum amount of boron (12.9 at. pct). In addition, raising the current density (from 10 to 70 mA/cm2) and reducing the duty cycle from 80 down to 20 pct gave rise to the reduction of surface roughness and the addition of tungsten content from 29.3 to 40.4 wt pct in the matrix. These effects improve corrosion resistances of coatings so that at the pulse duty cycle of 20 pct, by increasing the average current density from 10 to 70 mA/cm2, the corrosion current density declines from 9.8 to 2.1 µA/cm2 and the charge transfer raises from 3.1 to 20.4 KΩ cm2. Improvement of wear resistance observed by raising the plating current density could be related to the smoother surface and less brittle nature of coatings. The coating wear resistance improves with increasing plating current density up to 70 mA/cm2, seen in the reduction of the wear weight loss (from 1.1 to 0.41 mg/cm2) and friction coefficient (from 0.71 to 0.42).

Genetic Demography of the Population of St. Petersburg: Migration Processes

The principal genetic demographic parameters that describe migration processes affecting the structure of the St. Petersburg population gene pool were determined on the basis of the demographic statistics obtained from the Petrostat Agency, All-Russian population censuses, and a sample survey of St. Petersburg residents. The migration coefficient was 0.36 according to the survey data, 0.42 according to the 2002 census, 0.44 according to the 2010 census, and 0.69 according to the 1897 census. The estimated average migration distance was 1746 km from the survey data, 1526 km according to the 2002 census, and 1652 km according to the 2010 census. The sources of the St. Petersburg population gene pool in different periods are discussed: in the 18th and 19th centuries, the main source was the population of the Upper Volga and Northwestern provinces of the Russian Empire, as well as foreign immigrants, whereas currently three quarters of the population gene pool originates from the Northwestern Federal District, 10% comes from natives of foreign countries, and only 6–9% is due to the population of the Central Federal District of the Russian Federation. An analysis of the Rosstat migration statistics showed that the composition of migrants by countries of exit varied over time. For instance, the share of migrants who arrived in St. Petersburg from Russia in the last five years ranged from 74 to 87%. In 2013–2014, most international migrants came from Uzbekistan (10% of all arrivals) and Tajikistan (3–4%), while in 2017, the countries with the highest number of migrants ranked as follows: Kyrgyzstan (almost 4%), Ukraine (about 2%), Belarus (1.5%), Kazakhstan (1.25%), and Armenia (1%). Migration processes determine the dynamics of the ethnic composition of the population. Gender differences in migration flows are manifested in different age structure and in unequal sex ratio within particular ethnic groups (e.g., predominance of men in the “young” ethnic diasporas: Armenians, Azerbaijani, and Uzbeks). The described features of migration processes in St. Petersburg should be taken into account when forming genetic marker databases for the purposes of DNA-based identification. The areas of migration attraction of St. Petersburg and Moscow overlap only partially, which predetermines the need to create separate databases for each megacity.

RADIOGRAPHIC EVALUATION OF EARLY OUTCOME AFTER TWO TYPES OF CEMENTLESS HIP ARTHROPLASTY

Introduction Total Hip Arthroplasty is one of the most common orthopaedic procedures. Its outcome is assessed by radiographic evaluation. Two principal radiographic parameters are cup inclination and stem position angle. Aim The study aimed to compare radiological outcomes of two total hip arthroplasty techniques: Alloclassic Zweymüller versus Corail Pinnacle endoprostheses. Material and methods Medical histories of 345 patients who had a hip replacement between 2007 and 2017 were reviewed. Patients with primary total hip arthroplasty with both of mentioned systems were included in the research. Seven observers individually evaluated the radiological images of the 67 endoprostheses (39 Alloclassic Zweymüller and 26 Corail Pinnacle). The cup inclination and the stem position angle were measured using MB-Ruler programme. Results There was no statistical difference (p &gt; 0.338) in cup inclination angle between Alloclassic Zweymüller and Pinnacle cups, with the angle ranging from 31.01° to 58.80° (45.20° on average) and from 30.61° to 59.1° (43.60° on average), respectively. Femoral stem position did not differ between both types of endoprosthesis (p &gt; 0.932), ranging from −1.05° to 7.87° (3.09° on average) for Alloclassic Zweymüller and 0.35° to 7.79° (3.06° on average) for Corail Pinnacle stem. ICC (Intraclass Coefficient Correlation) was estimated and their 95% confident intervals were calculated for cup inclination and stem position showing good reliability of cup inclination measurements. Conclusions Both types of endoprostheses presented similar radiological outcomes. Cup inclination can be used by non-experienced medical staff to reliably assess the postoperative radiograms. Keywords: cementless hip replacement, radiological outcomes, imaging.

A New Framework for Pit Growth Stability and Its Experimental Validation

A new framework has been developed in recent works to describe pit growth stability 1-4. In this framework, the concept of maximum pit dissolution current density, i diss,max, was proposed to consider the competition between the dissolution and diffusion processes within a pit 2, 3, an issue that has not been satisfactorily addressed previously. The quantity i diss,max is the rate of dissolution in a pit in the absence of a salt film. According to this new framework, the pit stability and salt film formation can be defined by the critical conditions of i diss,max = i diff,crit and i diss,max = i lim, respectively, where i diff,crit and i lim are diffusion current densities related to maintain critical and saturated pit concentration 3. Unifying sets of principal parameters for pit stability and salt film formation were developed based on these critical conditions: (T crit, E crit, r crit) and (T sat, E sat, r sat), respectively 3. This talk described experiments using 1D artificial pit electrodes that validate this new framework for pit stability. According to the model prediction, the critical potential for salt film formation (E sat) should decrease with the log of pit depth. The results from experiments on 1D pits followed this relationship exactly, which provides strong support of the validity of the new model. Additionally, a critical pit concentration equal to 43% of the saturation concentration, C sat, was determined, which is much lower than the critical concentration determined by others. Furthermore, i diss,max values at fixed pit surface solution concentrations (100%C sat and 70%C sat) were determined using pits of varying depth. The Tafel slope was found to be about 116 mV in both environments. This is the first ever determination of pit dissolution kinetics in pit solutions of fixed concentration. This new framework provides an opportunity to revisit several key topics of this field and generates new insights to interpret previous observations in a self-consistent way, such as to understand the effects of alloy composition, bulk chloride concentration, ohmic potential drop of the solution, etc. Acknowledgments: This work was supported as part of the Center for Performance and Design of Nuclear Waste Forms and Containers, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award # DE-SC0016584. Reference G. S. Frankel, T. Li and J. R. Scully, Journal of the Electrochemical Society 164, C180-C181 (2017).T. Li, J. R. Scully and G. S. Frankel, Journal of The Electrochemical Society 165, C484-C491 (2018).T. Li, J. R. Scully and G. S. Frankel, Journal of The Electrochemical Society 165, C762-C770 (2018).T. Li, J. R. Scully and G. S. Frankel, Journal of The Electrochemical Society 166, C115-C124 (2019).

Preparation and characterization of metal organic framework-derived nanoporous carbons for highly efficient removal of vanadium from aqueous solution

The highly nanoporous carbon (NPC) materials were synthesized by carbonizing highly crystalline MOF-199 with addition carbon precursors and without any carbon precursors. In addition, a novel NPC@CNT was fabricated by the use of multi-walled carbon nanotubes (CNT) as carbon precursors and MOF-199 as the template. The morphology, structure, and surface properties of the synthesized NPC samples were characterized in detail. The NPC materials were employed as adsorbents for the removal of vanadium (V) from aqueous media by batch process. The effects of principal operational parameters on the adsorption of V ions are investigated, and the reaction mechanism for this treatment technology is also proposed. In order to determine the controlling mechanism of the adsorption process, the adsorption isotherms, kinetics and thermodynamics parameters were examined. The V adsorption onto NPC adsorbents can be best described with Langmuir isotherm points out the homogeneous surface sites of NPCs and also the monolayer formation of V ions on the adsorbent outer surface. The kinetic batch experiments revealed that more than the V ions were absorbed onto the synthesized NPCs within 15 min, and the pseudo-second-order kinetic model could explain the adsorption process. The thermodynamic study indicated that the adsorption process was exothermic and spontaneous and the system disorder increased during the adsorption process. The adsorbents showed preferential V ions adsorption with the existence of co-existing cation (Ni2+) and anions (SO42− and NO3−). The V adsorbed NPCs were regenerated with an efficiency of greater than 95% using 0.5 M sodium hydroxide.

A Metagenomic-Based Approach for the Characterization of Bacterial Diversity Associated with Spontaneous Malolactic Fermentations in Wine.

This study reports the first application of a next generation sequencing (NGS) analysis. The analysis was designed to monitor the effect of the management of microbial resources associated with alcoholic fermentation on spontaneous malolactic consortium. Together with the analysis of 16S rRNA genes from the metagenome, we monitored the principal parameters linked to MLF (e.g., malic and lactic acid concentration, pH). We encompass seven dissimilar concrete practices to manage microorganisms associated with alcoholic fermentation: Un-inoculated must (UM), pied-de-cuve (PdC), Saccharomyces cerevisiae (SC), S. cerevisiae and Torulaspora delbrueckii co-inoculated and sequentially inoculated, as well as S. cerevisiae and Metschnikowia pulcherrima co-inoculated and sequentially inoculated. Surprisingly, each experimental modes led to different taxonomic composition of the bacterial communities of the malolactic consortia, in terms of prokaryotic phyla and genera. Our findings indicated that, uncontrolled AF (UM, PdC) led to heterogeneous consortia associated with MLF (with a relevant presence of the genera Acetobacter and Gluconobacter), when compared with controlled AF (SC) (showing a clear dominance of the genus Oenococcus). Effectively, the SC trial malic acid was completely degraded in about two weeks after the end of AF, while, on the contrary, malic acid decarboxylation remained uncomplete after 7 weeks in the case of UM and PdC. In addition, for the first time, we demonstrated that both (i) the inoculation of different non-Saccharomyces (T. delbrueckii and M. pulcherrima) and, (ii) the inoculation time of the non-Saccharomyces with respect to S. cerevisiae resources (co-inoculated and sequentially inoculated) influence the composition of the connected MLF consortia, modulating MLF performance. Finally, we demonstrated the first findings of delayed and inhibited MLF when M. pulcherrima, and T. delbrueckii were inoculated, respectively. In addition, as a further control test, we also assessed the effect of the inoculation with Oenococcus oeni and Lactobacillus plantarum at the end of alcoholic fermentation, as MLF starter cultures. Our study suggests the potential interest in the application of NGS analysis, to monitor the effect of alcoholic fermentation on the spontaneous malolactic consortium, in relation to wine.