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Molecules ◽  
2022 ◽  
Vol 27 (1) ◽  
pp. 316
Author(s):  
Zhongqi He ◽  
Sunghyun Nam ◽  
Hailin Zhang ◽  
Ocen Modesto Olanya

Common “glanded” (Gd) cottonseeds contain the toxic compound gossypol that restricts human consumption of the derived products. The “glandless” (Gl) cottonseeds of a new cotton variety, in contrast, show a trace gossypol content, indicating the great potential of cottonseed for agro-food applications. This work comparatively evaluated the chemical composition and thermogravimetric behaviors of the two types of cottonseed kernels. In contrast to the high gossypol content (3.75 g kg−1) observed in Gd kernels, the gossypol level detected in Gl kernels was only 0.06 g kg−1, meeting the FDA’s criteria as human food. While the gossypol gland dots in Gd kernels were visually observed, scanning electron microcopy was not able to distinguish the microstructural difference between ground Gd and Gl samples. Chemical analysis and Fourier transform infrared (FTIR) spectroscopy showed that Gl kernels and Gd kernels had similar chemical components and mineral contents, but the former was slightly higher in protein, starch, and phosphorus contents. Thermogravimetric (TG) processes of both kernels and their residues after hexane and ethanol extraction were based on three stages of drying, de-volatilization, and char formation. TG-FTIR analysis revealed apparent spectral differences between Gd and Gl samples, as well as between raw and extracted cottonseed kernel samples, indicating that some components in Gd kernels were more susceptible to thermal decomposition than Gl kernels. The TG and TG-FTIR observations suggested that the Gl kernels could be heat treated (e.g., frying and roasting) at an optimal temperature of 140–150 °C for food applications. On the other hand, optimal pyrolysis temperatures would be much higher (350–500 °C) for Gd cottonseed and its defatted residues for non-food bio-oil and biochar production. The findings from this research enhance the potential utilization of Gd and Gl cottonseed kernels for food applications.


2022 ◽  
Vol 32 (1) ◽  
pp. 41-48
Author(s):  
I. A. Ekimova

A new species of the family Coryphellidae, Coryphella alexanderi sp. nov. is described based on specimens collected in the Kuril Islands, NorthWest Pacific, from the upper sublittoral to 200 m depth. An integrative analysis was conducted, including a molecular phylogenetic analysis based on four markers (COI, 16S, H3, 28S), an automatic species delimitation method ABGD, and an analysis of the external and internal morphology using light and scanning electron microcopy. The distinctiveness of Coryphella alexanderi sp. nov. is well established both morphologically and genetically, and it differs from externally similar species in radular characters. Phylogenetically Coryphella alexanderi sp. nov. is closely related to Coryphella trophina, which occurs sympatrically in the same geographic and bathymetric ranges. Coryphella alexanderi sp. nov. appears to be restricted to the middle and northern Kuril Islands, which is consistent with the high numbers of endemic taxa in this area.


Author(s):  
Alberto Sensini ◽  
Michael H. Santare ◽  
Emily Eichenlaub ◽  
Ellen Bloom ◽  
Carlo Gotti ◽  
...  

Tendon and ligament injuries are triggered by mechanical loading, but the specific mechanisms are not yet clearly identified. It is well established however, that the inflection and transition points in tendon stress-strain curves represent thresholds that may signal the onset of irreversible fibrillar sliding. This phenomenon often results in a progressive macroscopic failure of these tissues. With the aim to simulate and replace tendons, electrospinning has been demonstrated to be a suitable technology to produce nanofibers similar to the collagen fibrils in a mat form. These nanofibrous mats can be easily assembled in higher hierarchical levels to reproduce the whole tissue structure. Despite the fact that several groups have developed electrospun tendon-inspired structures, an investigation of the inflection and transition point mechanics is missing. Comparing their behavior with that of the natural counterpart is important to adequately replicate their behavior at physiological strain levels. To fill this gap, in this work fascicle-inspired electrospun nylon 6,6 bundles were produced with different collector peripheral speeds (i.e., 19.7 m s–1; 13.7 m s–1; 7.9 m s–1), obtaining different patterns of nanofibers alignment. The scanning electron microcopy revealed a fibril-inspired structure of the nanofibers with an orientation at the higher speed similar to those in tendons and ligaments (T/L). A tensile mechanical characterization was carried out showing an elastic-brittle biomimetic behavior for the higher speed bundles with a progressively more ductile behavior at slower speeds. Moreover, for each sample category the transition and the inflection points were defined to study how these points can shift with the nanofiber arrangement and to compare their values with those of tendons. The results of this study will be of extreme interest for the material scientists working in the field, to model and improve the design of their electrospun structures and scaffolds and enable building a new generation of artificial tendons and ligaments.


2020 ◽  
Vol 307 ◽  
pp. 113-118
Author(s):  
Nor Syamilah Syamimi Mohd Abdillih ◽  
Norlida Kamarulzaman ◽  
Kelimah Elong ◽  
Mohd Sufri Mastuli

The effect of Cr and Ni substitution on electrochemical performance of layered LiCo0.9M0.1O2 (M=Cr and Ni) has been investigated. Partial substituted of LiCo0.9Cr0.1O2 and LiCo0.9Ni0.1O2 has been synthesized using a self-propagating combustion (SPC) method with annealing temperature of 700 ̊ C for 24 h. The starting materials used were metal nitrates and citric acid act as a combustion agent. The phase and crystalinity of the materials were characterized using X-Ray Diffraction (XRD) and results showed that the single phase and pure materials were obtained with no impurity peaks were detected. The morphology and particle sizes of samples also analyzed using Field Emission Scanning Electron Microcopy (FESEM). The electrochemical performances of the materials were measured by its charge-discharge cycling which carried out in the voltage range of 2.5 V to 4.5 V. The results from charge-discharge studies found that LiCo0.9Ni0.1O2 has better specific discharge capacity compared with LiCo0.9Cr0.1O2.


2020 ◽  
Vol 301 ◽  
pp. 195-201
Author(s):  
Nor Syamilah Syamimi Mohd Abdillih ◽  
Norlida Kamarulzaman ◽  
Kelimah Elong ◽  
Nurhanna Badar ◽  
Mohd Sufri Mastuli

LiCo0.9X0.1O2 (where X=Mn and Fe) were synthesized using self-propagating combustion (SPC) method using citric acid as a combustion agent. The precursors of LiCo0.9X0.1O2 were annealed at a temperature of 800 °C at 24 h. The phase and crystalinity of the materials were characterized using X-Ray Diffraction (XRD). All the materials were observed to be single and pure phase with no impurity peaks detected. The morphology and particle sizes of the materials were also analyzed using Field Emission Scanning Electron Microcopy (FESEM). Finally, the electrochemical performance of the materials was studied using charge-discharge cycling in the voltage range of 2.5 to 4.3 V. Based on the results from charge-discharge studies, Mn substituted cathode materials exhibit better specific discharge capacity compared with Fe substituted cathode materials.


Polymers ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1331 ◽  
Author(s):  
Maria Jorda ◽  
Sergi Montava-Jorda ◽  
Rafael Balart ◽  
Diego Lascano ◽  
Nestor Montanes ◽  
...  

This work shows the potential of binary blends composed of partially bio-based poly(ethyelene terephthalate) (bioPET) and fully bio-based poly(amide) 10,10 (bioPA1010). These blends are manufactured by extrusion and subsequent injection moulding and characterized in terms of mechanical, thermal and thermomechanical properties. To overcome or minimize the immiscibility, a glycidyl methacrylate copolymer, namely poly(styrene-ran-glycidyl methacrylate) (PS-GMA; Xibond™ 920) was used. The addition of 30 wt % bioPA provides increased renewable content up to 50 wt %, but the most interesting aspect is that bioPA contributes to improved toughness and other ductile properties such as elongation at yield. The morphology study revealed a typical immiscible droplet-like structure and the effectiveness of the PS-GMA copolymer was assessed by field emission scanning electron microcopy (FESEM) with a clear decrease in the droplet size due to compatibilization. It is possible to conclude that bioPA1010 can positively contribute to reduce the intrinsic stiffness of bioPET and, in addition, it increases the renewable content of the developed materials.


Materials ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 2010 ◽  
Author(s):  
Guangyu Zhang ◽  
Dao Wang ◽  
Jiawei Yan ◽  
Yao Xiao ◽  
Wenyan Gu ◽  
...  

Herein, the amino-capped TiO2 nanoparticles were synthesized using tetrabutyl titanate and amino polymers by a two-step sol-gel and hydrothermal method technique for the fabrication of functional cotton fabric. The prepared TiO2 nanoparticles and the treated cotton fabric were characterized by transmission electron microscope (TEM), X-ray diffraction (XRD), field emission scanning electron microcopy (FE-SEM) photocatalytic and antibacterial measurement. The results indicate the typical characteristic anatase form of the amino-capped TiO2 NPs with an average crystallite size of 14.9 nm. The treated cotton fabrics exhibit excellent antibacterial property and good photocatalytic degradation of methylene blue.


2018 ◽  
Vol 773 ◽  
pp. 123-127
Author(s):  
Yun Gao Cai ◽  
Xin Qi Li

SiO2colloidal particles at the size range of 270-910 nm were synthesized by hydrolysis of ethyl silicate (TEOS) in the mixed solvents of TEOS and water under the catalysis of ammonium water solution; the effect of the addition manner of the mixed solution of TEOS and ethanol through immediateness and drop by drop were discussed; besides, two dimentional (2-D) SiO2photonic crystals (PCs) with hexagonal arrangement structure were successfully prepared by the gravity sedimentation method. The X-ray diffraction (XRD) and scanning electron microcopy (SEM) were employed to analyze the crystallinity and morphology of the synthesized SiO2colloidal particles and the 2-D SiO2photonic crystals, the results show that during the progress of the synthesized SiO2colloidal particles by the Stöber method, the addition manner of the mixed solution of TEOS and ethanol through drop by drop instead of immediateness could avoid the double-sized SiO2colloidal particles in a certain extent effectively. The reasons for the experimental results in this investigation have been discussed.


2017 ◽  
Vol 8 ◽  
pp. 1932-1938 ◽  
Author(s):  
Şeyma Özcan ◽  
Aslıhan Güler ◽  
Tugrul Cetinkaya ◽  
Mehmet O Guler ◽  
Hatem Akbulut

Different polymorphs of MnO2 (α-, β-, and γ-) were produced by microwave hydrothermal synthesis, and graphene oxide (GO) nanosheets were prepared by oxidation of graphite using a modified Hummers’ method. Freestanding graphene/MnO2 cathodes were manufactured through a vacuum filtration process. The structure of the graphene/MnO2 nanocomposites was characterized using X-ray diffraction (XRD) and Raman spectroscopy. The surface and cross-sectional morphologies of freestanding cathodes were investigated by scanning electron microcopy (SEM). The charge–discharge profile of the cathodes was tested between 1.5 V and 4.5 V at a constant current of 0.1 mA cm−2 using CR2016 coin cells. The initial specific capacity of graphene/α-, β-, and γ-MnO2 freestanding cathodes was found to be 321 mAhg−1, 198 mAhg−1, and 251 mAhg−1, respectively. Finally, the graphene/α-MnO2 cathode displayed the best cycling performance due to the low charge transfer resistance and higher electrochemical reaction behavior. Graphene/α-MnO2 freestanding cathodes exhibited a specific capacity of 229 mAhg−1 after 200 cycles with 72% capacity retention.


2017 ◽  
Vol 748 ◽  
pp. 7-11
Author(s):  
Xiao Zhen Liu ◽  
Wei Ren Rong ◽  
Xiao Zhou Liu ◽  
Xiao Hui Ren ◽  
Jie Chen ◽  
...  

The cerium dioxide films were prepared with cerium foils as raw materials by anodization in Na2C2O4-NH3∙H2O-H2O-(CH2OH)2 electrolyte. The anodic cerium oxide film was heat treated at 550°C. The cerium dioxide films were characterized with X-ray diffraction (XRD), energy-dispersive analyses of X-ray (EDAX), Fourier transform infrared (FTIR) techniques and scanning electron microcopy (SEM), respectively. The anodic cerium oxide film is semi crystalline film. The heat treated anodic cerium oxide film at 550°C is the fluorite-structured cerium dioxide film, and the crystal structure of the cerium dioxide film becomes more complete than that of the anodic cerium oxide film. The cerium dioxide film is porous film. The water, ethylene glycol and CO2 are adsorbed in the anodic cerium oxide film. The adsorbing water, ethylene glycol and CO2 in the anodic cerium oxide film are removed at 550°C. The cerium dioxide film has strong absorption in the range of 1400~4000cm-1.


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