Insight on to Mechanical, Thermal, Long-Term, Hydrothermal, and Chemical Stability of PSf Based Membrane Systems for Separation of O2 /N2

2021 ◽  
Author(s):  
SUCHHANDA SWAIN ◽  
Lakshmi Unnikrishnan ◽  
Smita Mohanty ◽  
Sanjay K. Nayak
Keyword(s):  
Real Life ◽  
Gas Permeation ◽  
Separation Performance ◽  
Separation And Purification ◽  
Membrane Systems ◽  
The Stability ◽  
First Time ◽  
Selection Of ◽  
Optimum Separation

Abstract MMMs have been opened up a new window in gas separation and purification applications, but the actual viability can be reckoned on the basis of performance achieved in realistic feed conditions. This research highlights the selection of silica decorated graphene for the first time to prepare nanocomposite membranes. In the study, XRD, Raman, and UV validated the existence of the different fillers within the host Polysulfone (PSf), while TEM authenticated their distribution. The burst strength and thermal properties were also investigated. Besides, it covered a prudent step towards resolving the dominant ingredients, which routinely appraise the stability and durability of the membranes. These indexes are long-term gas permeation up to 120 hours coupled with sustainability against hydrothermal and chemical resistance under various conditions similar to real-life separation applications. Finally, the report demonstrated that the nanohybrid integrated membrane systems displayed optimum separation performance and stability than their parent counterparts: PSf/mSiO2, PSf/GO.

scholarly journals A SLR Pre-Processing Algorithm Based on Satellite Signature Effect

2021 ◽  
Vol 11 (19) ◽  
pp. 8880
Author(s):  
Bowen Guan ◽  
Cunbo Fan ◽  
Ning An ◽  
Ricardo Cesar Podesta ◽  
Dra Ana Pacheco ◽  
...  
Keyword(s):  
Mean Value ◽  
Observation Data ◽  
Short Term ◽  
Error Sources ◽  
Effect Model ◽  
The Mean ◽  
The Stability ◽  
First Time ◽  
Satellite Signature Effect

As one of the major error sources, satellite signature effect should be reduced or even erased from the distribution of the post-fit residuals to improve the ranging precision. A simulation of satellite signature effect removal process for normal point algorithm is conducted based on a revised model of satellite response, which fully considers the structural and distribution characteristics of retroreflectors. In order to eliminate both long-term and short-term satellite signature effect, a clipping method for SLR data processing is proposed by defining the clipping location as 5.6 mm away from the mean value of the long-term fit residuals to select effective returns for normal points. The results indicate that, compared to normal points algorithm, the RMS per NP of LAGEOS-1 observation data processed by the clipping method is reduced from 62.90 ± 9.9 mm to 56.07 ± 4.69 mm, and the stability of RMS is improved 53%. This study improves the satellite signature effect model and simulates the fluctuation of normal points caused by satellite signature effect for the first time. The new method based on the simulation of satellite signature effect has stronger robustness and applicability, which can further minimize the influence of satellite signature effect on the SLR production and significantly improve the data property.

scholarly journals Ectoparasites of the bats from karst caves of the nature reserve «Ichalkovsky Bor» (Nizhny Novgorod Region)

2018 ◽  
Vol 7 (4) ◽  
pp. 122-126
Author(s):  
Galina Anatolievna Fadeeva ◽  
Elena Evgenievna Boryakova
Keyword(s):  
Natural Habitats ◽  
Karst Caves ◽  
Central Russia ◽  
The Family ◽  
Volga Upland ◽  
The Stability ◽  
The One ◽  
Parasitic Mites ◽  
First Time

The fauna of parasitic mites of bats from the karst caves in the region of the Volga Upland was studied in 2004-2005. Six species of bats such as Daubentons water bat, Brandts bat, whiskered bat, pond bat, northern bat and long-eared bat were examined. 18 species of arthropods were detected, among them there are gamasid mites (10 species) and harvest mites (2 species). Leptotrombidium russicum (Oud., 1902) and Myotrombicula sp. were found for the first time in Central Russia. Spinturnix acuminatus (Koch, 1836), Steatonyssus spinosus (Willmann, 1936), Steatonyssus periblepharus (Kolenati, 1858), Macronyssus flavus (Kolenati, 1856) turned out to be the main group of parasites in this study. As for the insects flies of the family Nycteribiidae and fleas of the family Ischnopsyllidae were found. The cluster analysis of ectoparasite fauna has showed that they are more or less evenly distributed among all members of mixed colonies of bats, while there is no violation of specificity in the choice of hosts. Low values of the Berger-Parker index marked a lack of competition between species, which indicates the stability of parasitic communities formed on bats in mixed colonies and in natural habitats. This fact indicates a complex relationship between the parasites in the community on the one hand, and long-term existence of the community on the other hand. This, in its turn, shows that in long-evolving communities competitive relationships between parasites are obliterated, which gives them stability. Herewith the bat colony is used as an integral whole, although some parasitic species prefer certain types of hosts.

scholarly journals A Revised Surgical Strategy for the Distal Tibiofibular Interosseous Osteochondroma

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Huarui Yang ◽  
Kangquan Shou ◽  
Shijun Wei ◽  
Zhi Fang ◽  
Qiwen Hu ◽  
...  
Keyword(s):  
Clinical Outcome ◽  
Ankle Joint ◽  
Tibial Osteotomy ◽  
Term Outcome ◽  
Long Term Outcome ◽  
Potential Damage ◽  
The Stability ◽  
And Function ◽  
First Time

Osteochondroma is one of the most common benign bone tumor; however, the surgical treatment still remains a challenge for those that occur at the distal tibiofibular interosseous location. Previously, the transfibular approach has been successfully described, but the potential damage of the syndesmosis would give rise to the instability of the ankle joint and thus may result in the unfavorable long-term outcome. Here, a revised strategy which can protect the syndesmotic complex is introduced. From 2010 to 2017, eleven patients with the distal tibiofibular interosseous osteochondroma who underwent the revised surgery were collected. The distal fibular osteotomy and posterior tibial osteotomy were performed to keep the inferior syndesmosis intact for better stability of the ankle joint. Both the anterior tibiofibular ligaments (AITFL) and posterior tibiofibular ligaments (PITFL) have been preserved successfully, and thus, the stability of the ankle joint has been maintained due to our strategy. The VAS and AOFAS scores were utilized to assess the clinical outcome and function. Postoperatively, all the patients were pain-free and were able to wear the appropriate shoes at the last follow-up. Preoperative and postoperative AOFAS scores were 93.63±6.91 and 47.27±5.27 (P<0.05), respectively. Moreover, the average VAS score was 1.73±0.27 (compared with preoperative as 7.45±2.15, P<0.05), demonstrating obvious improvement after the operation. To our best knowledge, this is the first time to perform the resection of the distal tibial interosseous osteochondroma involving the fibula without interrupting the inferior syndesmotic complex especially the AITFL and PITFL. We believe that this strategy may pave a new way for optimized clinical outcome for these patients with distal tibiofibular interosseous osteochondroma. This clinical trial study is registered with number ChiCTR1900024690.

scholarly journals Selection Effects on Dishonest Behavior

2020 ◽  
Author(s):  
Petr Houdek ◽  
Štěpán Bahník ◽  
Marek Hudik ◽  
Marek Albert Vranka
Keyword(s):  
Laboratory Experiments ◽  
Opposite Effect ◽  
Experimental Studies ◽  
Real Life ◽  
Selection Effects ◽  
Random Assignment ◽  
Factors Influencing ◽  
Social Proof ◽  
First Time ◽  
Selection Of

Many experimental studies use random assignment to identify factors influencing dishonesty. However, in real-life, people deliberately choose dishonesty-enabling environments. In two laboratory experiments, we let participants self-select in two tasks, one of which enabled them to cheat. We found that participants low in the honesty-humility were more likely to choose the cheating-enabling task. Furthermore, after choosing it, they cheated even more than when they were randomly assigned to it for the first time. When choosing the cheating-enabling task was costly, the interest in it decreased, but those who chose the task anyway cheated even more. An intervention based on social proof aimed to discourage self-selection into the cheating-enabling environment had the opposite effect. The results suggest that immoral individuals are likely to dominate cheating-enabling environments, where they cheat extensively. Interventions trying to limit the choice of these environments may backfire and lead to the selection of the worst fraudsters.

Multi-gene Genetic Programming for Structure Selection of Polynomial NARMAX models

2020 ◽  
Author(s):  
Henrique Carvalho de Castro ◽  
Bruno Henrique Groenner Barbosa
Keyword(s):  
Real Life ◽  
Search Space ◽  
Average Performance ◽  
Structure Selection ◽  
Pumping System ◽  
One Step ◽  
Simulation Error ◽  
High Degree ◽  
Selection Of

In the area of black-box identication, NARMAX models are of great interest. The main diculty faced when working with such models is the selection of the correct structure to represent the underlying system in the data. Orthogonal Least Squares (OLS) methods are widely used for this task, however, there are systems with a high degree of non-linearity and long term dependencies, which makes the use of traditional OLS methods computationally impracticable. In this sense, this paper studies the use of Multi-Gene Genetic Programing (MGGP) together with the traditional OLS method to increase the search space and turn the structure selection practicable for average performance computer. It is shown that, in real-life problem data, the algorithm can nd better models than previous works' models. The MGGP found a model for a hydraulic pumping system with a better one-step-ahead prediction error (0:058 mlc2 against 0:070 mlc2) using PEM technique and better free-run simulation error (0:997 mlc2 against 1:120 mlc2) using SEM technique. The MGGP found a model with such a degree of non-linearity and maximum input-output lags that totalizes 142505 candidate terms for traditional OLS analysis, which is impracticable for average performance computers.

scholarly journals When to start and when to stop antifibrotic therapies

2017 ◽  
Vol 26 (145) ◽  
pp. 170053 ◽  
Author(s):  
Sebastiano Emanuele Torrisi ◽  
Mauro Pavone ◽  
Ada Vancheri ◽  
Carlo Vancheri
Keyword(s):  
Early Stage ◽  
Real Life ◽  
Preliminary Evidence ◽  
Scientific Data ◽  
Safety Issues ◽  
Safety Studies ◽  
Lung Failure ◽  
Post Hoc ◽  
First Time

Idiopathic pulmonary fibrosis (IPF) is characterised by progressive changes of the lung architecture causing cough and dyspnoea and ultimately leading to lung failure and death. Today, for the first time, two drugs that may reduce the inexorable progression of the disease are available, suggesting that treatment with specific drugs for IPF should be started as soon as diagnosis is made. This applies to any disease and particularly to IPF, which is marked by a 5-year survival comparable or even worse than many cancers. However, despite common sense and even worse, in spite of scientific data coming from clinical trials, post hoc analysis, long-term safety studies and real-life experiences, the question of when to start and when to stop treatment with antifibrotics is still debated. In IPF, particularly when the disease is diagnosed at an early stage, “wait and watch” behaviour is not rare to observe. This is largely due to the lack of awareness of both patients and clinicians regarding the progression of the disease and its prognosis. Another important issue is when treatment should be stopped. In general, there are two main reasons to stop a therapy: unbearable side-effects and/or lack of efficacy. According to current (although preliminary) evidence, antifibrotic drugs should not be discontinued except for safety issues.

scholarly journals Solving a Real-Life Distributor’s Pallet Loading Problem

2021 ◽  
Vol 26 (3) ◽  
pp. 53
Author(s):  
Mauro Dell’Amico ◽  
Matteo Magnani
Keyword(s):  
Bin Packing ◽  
Real Life ◽  
Second Phase ◽  
Pallet Loading ◽  
Minimum Number ◽  
Loading Problem ◽  
The Difference ◽  
Two Phases ◽  
The Stability ◽  
Selection Of

We consider the distributor’s pallet loading problem where a set of different boxes are packed on the smallest number of pallets by satisfying a given set of constraints. In particular, we refer to a real-life environment where each pallet is loaded with a set of layers made of boxes, and both a stability constraint and a compression constraint must be respected. The stability requirement imposes the following: (a) to load at level k+1 a layer with total area (i.e., the sum of the bottom faces’ area of the boxes present in the layer) not exceeding α times the area of the layer of level k (where α≥1), and (b) to limit with a given threshold the difference between the highest and the lowest box of a layer. The compression constraint defines the maximum weight that each layer k can sustain; hence, the total weight of the layers loaded over k must not exceed that value. Some stability and compression constraints are considered in other works, but to our knowledge, none are defined as faced in a real-life problem. We present a matheuristic approach which works in two phases. In the first, a number of layers are defined using classical 2D bin packing algorithms, applied to a smart selection of boxes. In the second phase, the layers are packed on the minimum number of pallets by means of a specialized MILP model solved with Gurobi. Computational experiments on real-life instances are used to assess the effectiveness of the algorithm.

scholarly journals Long-term retainment of some chromosomal inversions in a local population of Belgica antarctica Jacobs (Diptera, Chironomidae)

2021 ◽  
Vol 11 (1) ◽  
pp. 16-24
Author(s):  
Paraskeva Michailova ◽  
Julia Ilkova ◽  
Pavlo Kovalenko ◽  
Artem Dzhulai ◽  
Iryna Kozeretska
Keyword(s):  
Classical Method ◽  
Local Population ◽  
Preparation Technique ◽  
Squash Preparation ◽  
Belgica Antarctica ◽  
Chromosome Iii ◽  
The Stability ◽  
Chromosome I ◽  
First Time

Genome of antarctic endemic Belgica antarctica Jacobs has been sequenced. However, no set of inversion diagnostic markers has ever been assigned for the species. Using the classical method of polytene chromosome squash preparation, we found three heterozygous inversions located on the second (two heterozygous inversions) and third chromosomes (one heterozygous inversion) in the Belgica antarctica population of a cape of Wiencke Island, 500 m to SW from Port Lockroy. The chromosome set and chromosome variability did not differ from those described in the literature (Atchley and Davis 1979). Every salivary gland chromosome had its own markers by which it can be determined. However, we did not find a sex-linked inversion on chromosome III and heterozygous inversion on chromosome I, reported in earlier studies. For the first time, we observed a strong heterochromatin band in chromosome III at the telomere of one arm. Our data show not only the stability of the described inversions in the population but also the usefulness of the squash preparation technique in the studies of genetic variability of Belgica antarctica in present time.

scholarly journals Long-term evaluation of scientific-echosounder performance

2009 ◽  
Vol 66 (6) ◽  
pp. 1335-1340 ◽  
Author(s):  
Hans Petter Knudsen
Keyword(s):  
Resource Assessment ◽  
Long Term Stability ◽  
Quantitative Measurements ◽  
Acoustic Instruments ◽  
Term Evaluation ◽  
Degree Of Confidence ◽  
The Stability ◽  
Calibration Time ◽  
First Time

Abstract Knudsen, H. P. 2009. Long-term evaluation of scientific-echosounder performance. – ICES Journal of Marine Science, 66: 1335–1340. When scientific acoustic instruments are utilized for quantitative measurements of underwater biological resources, it is extremely important to know their overall performance, and it is imperative to measure their stability over time. Echosounders mounted on research vessels are therefore routinely calibrated several times annually, often immediately before, during, and after important resource-assessment surveys. In recent years, multifrequency systems for acoustic surveys requiring species identification and categorization based on the frequency response of targets have been introduced, further emphasizing the importance of monitoring instrument performance. In the 1970s, hydrophones and steel spheres were used as alternative references for calibrations. Substantial variations of system performance were observed, however, and gradually it was accepted that the use of hydrophones was inappropriate, because their performance varied more than that of the instruments being calibrated. Not until optimized reference targets were introduced in ca. 1980, was it possible to monitor the stability of acoustic-survey equipment with an acceptable degree of confidence. For the first time, the true, long-term stability of transducers, including ageing effects, could be accurately measured. This paper gives examples of calibration time-series for several Norwegian research vessels operating in various regions from Arctic to tropical waters.

scholarly journals The Gaia-ESO Survey: open clusters in Gaia-DR1

2018 ◽  
Vol 612 ◽  
pp. A99 ◽  
Author(s):  
S. Randich ◽  
E. Tognelli ◽  
R. Jackson ◽  
R. D. Jeffries ◽  
S. Degl’Innocenti ◽  
...  
Keyword(s):  
Bayesian Analysis ◽  
Open Clusters ◽  
Evolutionary Models ◽  
Cluster Membership ◽  
Open Star ◽  
Bona Fide ◽  
First Time ◽  
Open Star Cluster ◽  
Selection Of

Context. Determination and calibration of the ages of stars, which heavily rely on stellar evolutionary models, are very challenging, while representing a crucial aspect in many astrophysical areas. Aims. We describe the methodologies that, taking advantage of Gaia-DR1 and the Gaia-ESO Survey data, enable the comparison of observed open star cluster sequences with stellar evolutionary models. The final, long-term goal is the exploitation of open clusters as age calibrators. Methods. We perform a homogeneous analysis of eight open clusters using the Gaia-DR1 TGAS catalogue for bright members and information from the Gaia-ESO Survey for fainter stars. Cluster membership probabilities for the Gaia-ESO Survey targets are derived based on several spectroscopic tracers. The Gaia-ESO Survey also provides the cluster chemical composition. We obtain cluster parallaxes using two methods. The first one relies on the astrometric selection of a sample of bona fide members, while the other one fits the parallax distribution of a larger sample of TGAS sources. Ages and reddening values are recovered through a Bayesian analysis using the 2MASS magnitudes and three sets of standard models. Lithium depletion boundary (LDB) ages are also determined using literature observations and the same models employed for the Bayesian analysis. Results. For all but one cluster, parallaxes derived by us agree with those presented in Gaia Collaboration (2017, A&A, 601, A19), while a discrepancy is found for NGC 2516; we provide evidence supporting our own determination. Inferred cluster ages are robust against models and are generally consistent with literature values. Conclusions. The systematic parallax errors inherent in the Gaia DR1 data presently limit the precision of our results. Nevertheless, we have been able to place these eight clusters onto the same age scale for the first time, with good agreement between isochronal and LDB ages where there is overlap. Our approach appears promising and demonstrates the potential of combining Gaia and ground-based spectroscopic datasets.

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