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2022 ◽  
Vol 9 ◽  
Author(s):  
Soni Tiwari ◽  
Janardan Yadav ◽  
Rajeeva Gaur ◽  
Ranjan Singh ◽  
Tuhina Verma ◽  
...  

The enzymatic saccharification of sugarcane bagasse was significantly increased by alkali pretreatment under mild conditions. The effectiveness of different concentrations of alkali and acid pretreatment of sugarcane bagasse for improving the enzymatic saccharification of lignocellulose has been evaluated. The sugarcane bagasse was characterized to contain 39.52% celluloses, 25.63% hemicelluloses, and 30.36% lignin. After that, sugarcane bagasse was pretreated with 5 and 10% of H2SO4 and NaOH at 121°C for 60 min. FTIR, XRD, and SEM analyses also showed significant molecular and surface structure changes of the sugarcane bagasse with 10% NaOH. Maximum saccharification was 489.5 mg/g from 10% NaOH pretreatment followed by 322.75, 301.25, and 276.6 mg/g from 10% H2SO4, 5% NaOH, and 5% H2SO4, respectively, which were 55.1, 32.0, 27.1, and 20.6 times higher than the that of the control. Cellulase and xylanase produced by Pseudomonas sp. CVB-10 (MK443365) and Bacillus paramycoides T4 (MN370035) were used to hydrolyze the pretreated bagasse, and the optimal condition was determined to be 30 h of the enzymatic reaction with the 3:1 ratio of enzymes under the temperature of 55°C, pH 5.0, and substrate concentration of 3%, leading to celluloses and hemicelluloses conversion in the enzymatic hydrolysis/saccharification that is more proficient.


PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0262076
Author(s):  
Michal Granot ◽  
Einav Srulovici ◽  
Yelena Granovsky ◽  
David Yarnitsky ◽  
Pora Kuperman

Pain variability can be partially attributed to psycho-cognitive features involved in its processing. However, accumulating research suggests that simple linear correlation between situational and dispositional factors may not be sufficiently explanatory, with some positing a role for mediating influences. In addition, acute pain processing studies generally focus on a post-operative model with less attention provided to post-traumatic injury. As such, this study aimed to investigate a more comprehensive pain processing model that included direct and indirect associations between acute pain intensity in the head and neck, pain catastrophizing (using pain catastrophizing scale (PCS)), and pain sensitivity (using the pain sensitivity questionnaire (PSQ)), among 239 patients with post-motor vehicle collision pain. The effect of personality traits (using Ten Items Personality Inventory (TIPI)) and emotional status (using Hospital Anxiety and Depression Scale (HADS) and Perceived Stress Scale (PSS)) on that model was examined as well. To this end, three Structural Equation Modeling (SEM) analyses were conducted. Overall, the data had good fit to all the models, with only PSQ found to have a direct correlation with acute pain intensity. The SEM analyses conversely revealed several mediations. Specifically, that: first, PSQ fully mediated the relationship between PCS and pain intensity; second, PCS and PSQ together fully mediated the relationship between conscientiousness (personality trait) and pain intensity; and finally, emotional status had direct and indirect links with PSQ and pain intensity. In conclusion, these models suggest that during the acute post-collision phase, pain sensitivity intermediates between emotional states and personality traits, partially via elevated pain catastrophizing thoughts.


Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7646
Author(s):  
Marek Grabowy ◽  
Kamil Wojteczko ◽  
Agnieszka Wojteczko ◽  
Grzegorz Wiązania ◽  
Maciej Łuszcz ◽  
...  

An alumina-toughened zirconia (ATZ) material, fabricated using a procedure consisting of the common sintering of two different zirconia powders, was tested using the ball-on-disc method in a temperature range between room temperature and 500 °C. Corundum balls were used as a counterpart. The ATZ composite behaviour during tests was compared with that of commonly used α-alumina and tetragonal zirconia sintered samples. At temperatures over 350 °C, a drastic decrease in the wear rate of the material was detected. SEM analyses proved that, in such conditions, nearly the whole surface of the sliding material was covered with a layer of deformed submicrometric grains, which limited contact with the part of material that was not deformed. The mentioned layer was relatively strongly connected with the material, increased its resistance, and decreased its coefficient of friction. As a reference, commonly used materials, namely commercial alumina and tetragonal zirconia, were tested. The wear parameters of the composite were significantly better than those registered for the materials prepared of commercial powders.


Entropy ◽  
2021 ◽  
Vol 23 (12) ◽  
pp. 1632
Author(s):  
Bin Zhang ◽  
Yu Tang ◽  
Shun Li ◽  
Yicong Ye ◽  
Li’an Zhu ◽  
...  

To determine the effects of Ti and mixing entropy (ΔSmix) on the structure and mechanical proper-ties of Zr-Ta alloys and then find a new potential energetic structural material with good me-chanical properties and more reactive elements, TixZr2.5−xTa (x = 0, 0.5, 1.0, 1.5, 2.0) alloys were investigated. The XRD experimental results showed that the phase transformation of TixZr2.5−xTa nonequal-ratio ternary alloys depended not on the value of ΔSmix, but on the amount of Ti atoms. With the addition of Ti, the content of the HCP phase decreased gradually. SEM analyses revealed that dendrite morphology and component segregation increasingly developed and then weakened gradually. When x increases to 2.0, TixZr2.5−xTa with the best mechanical properties can be ob-tained. The yield strength, compressive strength and fracture strain of Ti2.0Zr0.5Ta reached 883 MPa, 1568 MPa and 34.58%, respectively. The dependence of the phase transformation and me-chanical properties confirms that improving the properties of Zr-Ta alloys by doping Ti is feasible.


Phytotaxa ◽  
2021 ◽  
Vol 527 (2) ◽  
pp. 97-106
Author(s):  
İSMAİL EKER ◽  
MEHMET SAĞIROĞLU

Gladiolus izzet-baysalii is described and illustrated as a new species from Karaman province in Southern Anatolia. Gladiolus izzet-baysalii is not morphologically close to any of the species of Gladiolus in Turkey. Although it has some similarities with G. illyricus and G. hamzaoglui in terms of habitus, G. izzet-baysalii differs significantly in tunic structure, number of leaves, inflorescence, perianth, anther, style, capsule and seed features. In this study, the diagnostic morphological features, distribution, conservation status, habitat and ecological characteristics of the new species are discussed. Micromorphological characteristics of G. izzet-baysalii, G. illyricus and G. hamzaoglui seeds are also examined and compared using stereomicroscope and SEM analyses.


2021 ◽  
Vol 9 ◽  
Author(s):  
Malihe Zeraati ◽  
Ali Mohammadi ◽  
Somayeh Vafaei ◽  
Narendra Pal Singh Chauhan ◽  
Ghasem Sargazi

In this paper, we have reported an innovative greener method for developing copper-metal organic frameworks (Cu-MOFs) using caffeic acid (CA) as a linker extracted from Satureja hortensis using ultrasonic bath. The density functional theory is used to discuss the Cu-MOF-binding reaction mechanism. In order to achieve a discrepancy between the energy levels of the interactive precursor orbitals, the molecules have been optimized using the B3LYP/6–31G method. The Taguchi method was used to optimize the key parameters for the synthesis of Cu-MOF. FT-IR, XRD, nitrogen adsorption, and SEM analyses are used to characterize it. The adsorption/desorption and SEM analyses suggested that Cu-MOF has a larger surface area of 284.94 m2/g with high porosity. Cu-MOF has shown anticancer activities against the human breast cancer (MDA-MB-468) cell lines, and it could be a potent candidate for clinical applications.


Author(s):  
Einar M. Skaalvik ◽  
Sidsel Skaalvik

AbstractOne purpose of this study was to analyze relations between four possible indicators of a collective teacher culture by means of confirmatory factor analyses. The indicators were termed “shared goals values”, “value consonance”, “collective teacher efficacy”, and “supportive colleagues”. A second purpose was to explore relations between collective teacher culture and teachers’ experiences of autonomy, belonging, and job satisfaction. Participants were 760 Norwegian teachers in elementary school and middle school. The data were analyzed by means of confirmatory factor analyses and SEM analyses. The correlations between the four indicators of a collective culture ranged from .44 to .63 and both a model with first order factors and a model with a second order collective culture variable had good fit to the data. The analysis showed that a second order collective teacher culture variable was strongly and positively associated with the teachers’ experiences of autonomy, belonging, and job satisfaction.


Biotecnia ◽  
2021 ◽  
Vol 23 (3) ◽  
Author(s):  
Héctor Manuel Guzmán Grijalva ◽  
Juana Alvarado Ibarra ◽  
Martín Francisco Zamarrón Pulé ◽  
Javier Esquer Peralta

A composite material was prepared using chitosan and chabazite for the removal of Eriochrome T black dye from water. Scanning electron microscopy (SEM) analyses showed chabazite particles embedded in the chitosan matrix. Thermogravimetric analyses indicated that chitosan degrades chemically at temperatures above 225 °C; chabazite only experiences weight decrease due to moisture loss. Fourier transform infrared spectroscopy (FTIR) analyses on chitosan detected the presence of O-H, N-H, C-H, C-N and C-O bonds, protonated amino groups and saccharides. In chabazite, H2O molecules, T-O and O-T-O groups, where “T” corresponds to Si or Al atoms, isolated H-bonded O-H groups, and Si-O-Si groups were detected. In kinetic experiments, an 86 % decrease of the dye concentration in solution was achieved in approximately 500 minutes. The linearization method was used to evaluate the fit of the experimental data with the pseudo-first-order, pseudo-second order, Elovich and intra-particle diffusion adsorption kinetic models. The kinetic experiments showed that the sorption mechanism corresponds to a pseudo-second order model.


2021 ◽  
Author(s):  
Zhe Zhu ◽  
Si Zhang ◽  
Chao Song ◽  
Ligong Wang ◽  
Fanfan Cai ◽  
...  

Abstract A large amount of eggplant straw (ES) is incinerated after harvesting of eggplant every year, which aggravates environmental pollution and waste of resources. Converting ES into methane through anaerobic digestion (AD) technology may be a potential treatment method, considering the low environmental impact and high energy recovery. Firstly, this study explored the effects of organic loading (OL) and feed to inoculum ratio (F/I ratio) on the AD of ES by response surface methodology (RSM). In order to achieve higher AD efficiency, various pretreatments (acid, alkali, alkaline hydrogen peroxide (AHP), microwave and ultrasound) were introduced and comprehensively assessed with regard to methane production performance, organic matter destruction and kinetic parameters. Results showed that OL had a more significant impact on AD process compared to F/I ratio and methane production was enhanced remarkably when the OL and F/I ratio were 35.0 g VS/L and 3.0, respectively. XRD, FTIR, and SEM analyses of pretreated ES showed that alkali and AHP pretreatments performed better in delignification. Under optimal conditions, the ES pretreated with 1.5% AHP (adjusted by KOH) performed the maximum methane production of 262.2 mL/g VS with a Bd of 95.0%, which increased by 334.1% than untreated ES. This paper not only provides the theoretical data about methane production performance of ES but also gives practical guidance for efficient utilization of similar vegetable straw biowastes, which is also promising for large-scale industrial applications in the future.


2021 ◽  
Vol 63 (9) ◽  
pp. 19-24
Author(s):  
Hong Quang Bui ◽  
◽  

This paper uses scanning electron microscopy (SEM) analyses and light microscopy (LM) to study pollen grains of species of the family Oleaceae Hoffmanns. & Link distributed in Vietnam, including 23 species belonging to 6 genera of the family (Oleaceae). Pollen grains of all species (Oleaceae) in Vietnam are isopolar, radial, 3- prolate pollen grains small size, with two types: subprolate type (Jasminum and Olea) and prolate spheroidal type (Jasminum, Fraxinus, Ligustrum, Osmanthus, and Chengiodendron). The surface of the pollen grains in most species is reticulate. These are important morphological features to classify the Nhai family through pollen morphology


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