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1.
J Sci Food Agric ; 104(5): 3039-3046, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38057148

RESUMO

BACKGROUND: Postmortem muscle moisture loss leads to a decrease in carcass weight and can adversely impact overall meat quality. Therefore, it is critical to investigate water holding capacity (WHC) to enhance meat quality. Current research has primarily focused on examining the correlation between signaling molecules and meat quality in relation to the glycolysis effect on muscle WHC. But there exists a significant knowledge gap regarding the mechanism of WHC in Jersey cattle-yak meat. RESULTS: Jersey cattle-yak meat pH decreased and then increased during postmortem aging. Lactate content, cooking loss, pressing loss, drip loss and centrifuging loss of Jersey cattle-yak meat increased and then decreased during postmortem aging. The glycogen content of Jersey cattle-yak meat was significantly higher than that of yak meat at 6-120 h, being 8.40% higher than that of yak meat at 120 h. The activity of key glycolytic enzymes hexokinase (HK), pyruvate kinase (PK), phosphofructokinase (PFK) and lactate dehydrogenase (LDH) in Jersey cattle-yak meat was lower than that in yak meat. Correlation analysis showed that Jersey cattle-yak meat WHC was positively correlated with the activity of HK, PK, PFK and LDH. CONCLUSIONS: The WHC of Jersey cattle-yak meat was higher than that of Gannan yak meat, and it was significantly positively correlated with the activity of key enzymes of the glycolytic signaling pathway. Therefore, the glycolysis rate can be reduced by inhibiting enzyme activity to improve Jersey cattle-yak meat WHC and meat quality. © 2023 Society of Chemical Industry.


Assuntos
Culinária , Água , Animais , Bovinos , Água/análise , Carne/análise , Glicólise , Músculo Esquelético/química
2.
Opt Express ; 31(2): 2373-2385, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785252

RESUMO

Wide bandwidth THz pulses can be used to record the distinctive spectral fingerprints related to the vibrational or rotational modes of polycrystalline biomolecules, and can be used to resolve the time-dependent dynamics of such systems. Waveguides, owing to their tight spatial confinement of the electromagnetic fields and the longer interaction distance, are promising platforms with which to study small volumes of such systems. The efficient input of sub-ps THz pulses into waveguides is challenging owing to the wide bandwidth of the THz signal. Here, we propose a sensing chip comprised of a pair of back-to-back Vivaldi antennas feeding into, and out from, a 90° bent slotline waveguide to overcome this problem. The effective operating bandwidth of the sensing chip ranges from 0.2 to 1.15 THz, and the free-space to on-chip coupling efficiency is as high as 51% at 0.44 THz. Over the entire band, the THz signal is ∼42 dB above the noise level at room temperature, with a peak of ∼73 dB above the noise. In order to demonstrate the use of the chip, we have measured the characteristic fingerprint of α-lactose monohydrate, and its sharp absorption peak at ∼0.53 THz was successfully observed, demonstrating the promise of our technique. The chip has the merits of efficient in-plane coupling, ultra-wide bandwidth, ease-of-integration, and simple fabrication. It has the potential for large-scale manufacture, and can be a strong candidate for integration into other THz light-matter interaction platforms.

3.
J Am Chem Soc ; 143(43): 18091-18102, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34664933

RESUMO

The increasing demand to efficiently store and utilize the electricity from renewable energy resources in a sustainable way has boosted the request for sodium-ion battery technology due to the high abundance of sodium sources worldwide. Na superionic conductor (NASICON) structured cathodes with a robust polyanionic framework have been intriguing because of their open 3D structure and superior thermal stability. The ever-increasing demand for higher energy densities with NASICON-structured cathodes motivates us to activate multielectron reactions, thus utilizing the third sodium ion toward higher voltage and larger capacity, both of which have been the bottlenecks for commercializing sodium-ion batteries. A doping strategy with Cr inspired by first-principles calculations enables the activation of multielectron redox reactions of the redox couples V2+/V3+, V3+/V4+, and V4+/V5+, resulting in remarkably improved energy density even in comparison to the layer structured oxides and Prussian blue analogues. This work also comprehensively clarifies the role of the Cr dopant during sodium storage and the valence electron transition process of both V and Cr. Our findings highlight the importance of a broadly applicable doping strategy for achieving multielectron reactions of NASICON-type cathodes with higher energy densities in sodium-ion batteries.

4.
Angew Chem Int Ed Engl ; 60(34): 18519-18526, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34096153

RESUMO

Manganese-based Prussian Blue, Na2-δ Mn[Fe(CN)6 ] (MnPB), is a good candidate for sodium-ion battery cathode materials due to its high capacity. However, it suffers from severe capacity decay during battery cycling due to the destabilizing Jahn-Teller distortions it undergoes as Mn2+ is oxidized to Mn3+ . Herein, the structure is stabilized by a thin epitaxial surface layer of nickel-based Prussian Blue (Na2-δ Ni[Fe(CN)6 ]). The one-pot synthesis relies on a chelating agent with an unequal affinity for Mn2+ and Ni2+ ions, which prevents Ni2+ from reacting until the Mn2+ is consumed. This is a new and simpler synthesis of core-shell materials, which usually needs several steps. The material has an electrochemical capacity of 93 mA h g-1 , of which it retains 96 % after 500 charge-discharge cycles (vs. 37 % for MnPB). Its rate capability is also remarkable: at 4 A g-1 (ca. 55 C) it can reversibly store 70 mA h g-1 , which is also reflected in its diffusion coefficient of ca. 10-8  cm2 s-1 . The epitaxial outer layer appears to exert an anisotropic strain on the inner layer, preventing the Jahn-Teller distortions it normally undergoes during de-sodiation.

5.
Angew Chem Int Ed Engl ; 59(29): 12076-12083, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32249496

RESUMO

Titanium-based polyanions have been intensively investigated for sodium-ion batteries owing to their superior structural stability and thermal safety. However, their low working potential hindered further applications. Now, a cation and anion dual doping strategy is used to boost the redox potential of Ti-based cathodes of Na3 Ti0.5 V0.5 (PO3 )3 N as a new cathode material for sodium ion batteries. Both the Ti3+ /Ti4+ and V3+ /V4+ redox couples are reversibly accessed, leading to two distinctive voltage platforms at ca. 3.3 V and ca. 3.8 V, respectively. The remarkably improved cycling stability (86.3 %, 3000 cycles) can be ascribed to the near-zero volume strain in this unusual cubic symmetry, which has been demonstrated by in situ synchrotron-based X-ray diffraction. First-principles calculations reveal its well-interconnected 3D Na diffusion pathways with low energy barriers, and the two-sodium-extracted intermediate NaTi0.5 V0.5 (PO3 )3 N is also a stable phase according to formation energy calculations.

6.
Macromol Rapid Commun ; 36(19): 1722-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26178692

RESUMO

Thermoresponsive photonic materials having hierarchical structures are created by combining a template of Morpho butterfly wings with poly(N-isopropylacrylamide) (PNIPAM) through a chemical bonding and polymerization route. These materials show temperature-induced color tunability. Through reacting with both NIPAM monomers and the amino groups of chitosan in wing scales, glutaraldehyde workes as a bridge by creating chemical bonding between the biotemplate and the PNIPAM. The corresponding reflection peaks red-shift with increase in temperature-an opposite phenomenon to previous studies, demonstrating a thermoresponsive photonic property. This unique phenomenon is caused by the refractive index change due to the volume change of PNIPAM during the temperature rising. This work sets up an efficient strategy for the fabrication of stimuli-responsive photonic materials with hierarchical structures toward extensive applications in science and technology.


Assuntos
Polímeros/química , Resinas Acrílicas/química , Quitosana/química , Glutaral/química , Microscopia Eletrônica de Varredura , Polímeros/síntese química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
7.
Int J Mol Sci ; 16(9): 21873-96, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26378520

RESUMO

The rice leaf roller (Cnaphalocrocis medinalis) is one of the most destructive agricultural pests. Due to its migratory behavior, it is difficult to control worldwide. To date, little is known about major genes of C. medinalis involved in chitin metabolism and insecticide detoxification. In order to obtain a comprehensive genome dataset of C. medinalis, we conducted de novo transcriptome sequencing which focused on the major feeding stage of fourth-instar larvae, and our work revealed useful information on chitin metabolism and insecticide detoxification and target genes of C. medinalis. We acquired 29,367,797 Illumina reads and assembled these reads into 63,174 unigenes with an average length of 753 bp. Among these unigenes, 31,810 were annotated against the National Center for Biotechnology Information non-redundant (NCBI nr) protein database, resulting in 24,246, 8669 and 18,176 assigned to Swiss-Prot, clusters of orthologous group (COG), and gene ontology (GO), respectively. We were able to map 10,043 unigenes into 285 pathways using the Kyoto Encyclopedia of Genes and Genomes Pathway database (KEGG). Specifically, 16 genes, including five chitin deacetylases, two chitin synthases, five chitinases and four other related enzymes, were identified to be putatively involved in chitin biosynthesis and degradation, whereas 360 genes, including cytochrome P450s, glutathione S-transferases, esterases, and acetylcholinesterases, were found to be potentially involved in insecticide detoxification or as insecticide targets. The reliability of the transcriptome data was determined by reverse transcription quantitative PCR (RT-qPCR) for the selected genes. Our data serves as a new and valuable sequence resource for genomic studies on C. medinalis. The findings should improve our understanding of C. medinalis genetics and contribute to management of this important agricultural pest.


Assuntos
Quitina/metabolismo , Genes de Insetos , Inativação Metabólica/genética , Inseticidas/metabolismo , Mariposas/genética , Mariposas/metabolismo , Transcriptoma , Animais , Análise por Conglomerados , Biologia Computacional/métodos , Resistência a Medicamentos/efeitos dos fármacos , Resistência a Medicamentos/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Redes Reguladoras de Genes , Sequenciamento de Nucleotídeos em Larga Escala , Larva , Repetições de Microssatélites , Anotação de Sequência Molecular , Mariposas/efeitos dos fármacos , Fases de Leitura Aberta , Reprodutibilidade dos Testes
8.
Opt Lett ; 39(14): 4208-11, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25121688

RESUMO

Butterflies routinely produce nanostructured surfaces with useful properties. Here, we report a disordered nano-hole structure with ridges inspired by Papilio ulysses that produce omnidirectional light absorption compared with the common ordered structure. The result shows that the omnidirectional light absorption is affected by polarization, the incident angle, and the wavelength. Using the finite-difference time-domain (FDTD) method, the stable omnidirectional light absorption is achieved in the structure inspired from the Papilio ulysses over a wide incident angle range and with various wavelengths. This explains some of the mysteries of the structure of the Papilio ulysses butterfly. These conclusions can guide the design of omnidirectional absorption materials.


Assuntos
Absorção de Radiação , Materiais Biomiméticos/síntese química , Borboletas/ultraestrutura , Luz , Nanoporos/ultraestrutura , Nanoestruturas/ultraestrutura , Asas de Animais/ultraestrutura , Animais , Teste de Materiais
9.
Materials (Basel) ; 17(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38541589

RESUMO

The slag entrapment defect has become a big issue for the IF steel casting process. In this study, the mechanism of mold flux entrapment in deep oscillation mark of an IF steel shell was studied by a high-temperature mold simulator. Results show that both temperature and heat flux in a copper mold become lower when mold flux B with lower melting and viscosity is used, compared with these when mold flux A with higher melting and viscosity is used. The average thickness of the slag film for mold fluxes A and B is 1.31 mm and 1.63 mm, and the consumption of them is 0.33 kg/m2 and 0.35 kg/m2, respectively. The shell for mold flux A exhibits sharper oscillation marks, while the shell for mold flux B has shallower oscillation marks. These deeper oscillation marks capture the mold flux by overflow of molten steel at the meniscus, which finally produces the slag entrapment defect in the shell.

10.
Food Chem X ; 22: 101327, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38590633

RESUMO

To investigate the effect of gelatin peptide on the inhibition of quality deterioration in stored pudding, gelatin peptide with antioxidant properties was added to pudding products. For this purpose, a pudding recipe containing gelatin peptides was created. The gelatin peptides were characterized based on their antioxidant activity and protein structure. It was found that gelatin peptides had better antioxidant properties, lower thermal stability and crystallinity, higher hydrophobic amino acid content, and greater surface hydrogen bond exposure than commercially available peptides. Properties such as the pH, colony growth, and sensory characteristics of the pudding were characterized at 4 °C and 25 °C. The results showed that the addition of 0.5-1.0 % gelatin peptide to pudding was capable of significantly (P< 0.05) slowing down the decline in pH and sensory scores of the pudding and significantly inhibiting colony growth. It could prolong its storage life by five days at 4 °C and three days at 25 °C.

11.
J Immunother Precis Oncol ; 7(1): 7-17, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38327755

RESUMO

Introduction: Genomic profiling is performed in patients with advanced or metastatic cancer, in order to direct cancer treatment, often sequencing tumor-only, without a matched germline comparator. However, because many of the genes analyzed on tumor profiling overlap with those known to be associated with hereditary cancer predisposition syndromes (HCPS), tumor-only profiling can unknowingly uncover germline pathogenic (P) and likely pathogenic variants (LPV). In this study, we evaluated the number of patients with P/LPVs identified in BRCA1 and BRCA2 (BRCA1/2) via tumor-only profiling, then determined the germline testing outcomes for those patients. Methods: A retrospective chart review was performed to identify patients with BRCA1/2 variants on tumor-only genomic profiling, and whether they had germline testing. Results: This study found that of 2923 patients with 36 tumor types who underwent tumor-only testing, 554 had a variant in BRCA1/2 (19.0%); 119 of the 554 patients (21.5%) had a P/LP BRCA1/2 variant, representing 4.1% of the overall population who underwent genomic profiling. Seventy-three (61.3%) of 119 patients with BRCA1/2 P/LPV on tumor-only testing did not undergo germline testing, 34 (28.6%) had already had germline testing before tumor-only testing, and 12 (10.1%) underwent germline testing after tumor-only testing. Twenty-eight germline BRCA1/2 P/LPVs were detected, 24 in those who had prior germline testing, and 4 among the 12 patients who had germline testing after tumor-only testing. Conclusion: Tumor-only testing is likely to identify P/LPVs in BRCA1/2. Efforts to improve follow-up germline testing is needed to improve identification of germline BRCA1/2 alterations.

12.
Opt Lett ; 38(2): 169-71, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23454951

RESUMO

The wide angular range of the treelike structure in Morpho butterfly scales was investigated by finite-difference time-domain (FDTD)/particle-swarm-optimization (PSO) analysis. Using the FDTD method, different parameters in the Morpho butterflies' treelike structure were studied and their contributions to the angular dependence were analyzed. Then a wide angular range was realized by the PSO method from quantitatively designing the lamellae deviation (Δy), which was a crucial parameter with angular range. The field map of the wide-range reflection in a large area was given to confirm the wide angular range. The tristimulus values and corresponding color coordinates for various viewing directions were calculated to confirm the blue color in different observation angles. The wide angular range realized by the FDTD/PSO method will assist us in understanding the scientific principles involved and also in designing artificial optical materials.


Assuntos
Borboletas/fisiologia , Cor , Óptica e Fotônica , Asas de Animais/química , Animais , Simulação por Computador , Luz , Teste de Materiais , Modelos Biológicos , Modelos Estatísticos , Processos Estocásticos
13.
Adv Sci (Weinh) ; 10(35): e2303452, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37888858

RESUMO

The multispectral compatible infrared camouflage technology is implemented these days to counter the developing infrared detectors and detectors of other bands. However, the conflict between delicate optical structures and scalable procedures has significantly impeded the development and application of multispectral-compatible camouflage technology. Therefore, a semi-open Fabry-Perot structure is introduced, and the color and infrared emissivity by structural parameters for color-matched visible-infrared compatible camouflage are modulated. The prepared compatible camouflage film exhibits visible camouflage by the minimum color difference of 1.6 L*a*b* (under desert background) and infrared camouflage by low emission (ε3-5 µm ≈ 0.17 and ε8-14 µm ≈ 0.143). Due to its flexibility and scalability, the compatible camouflage film can be applied in practical applications and exhibits desirable visible and infrared camouflage performance in different battlefield backgrounds.

14.
Front Surg ; 10: 1121292, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36911613

RESUMO

Introduction: Gasless unilateral trans-axillary approach (GUA) thyroidectomy has witnessed rapid development in technologies and applications. However, the existence of surgical retractors and limited space would increase the difficulty of guaranteeing the visual field and disturb safe surgical manipulation. We aimed to develop a novel zero-line method for incision design to access optimal surgical manipulation and outcomes. Methods: A total of 217 patients with thyroid cancer who underwent GUA were enrolled in the study. Patients were randomly classified into two groups (classical incision and zero-line incision), and their operative data were collected and reviewed. Results: 216 enrolled patients underwent and completed GUA; among them, 111 patients were classified into the classical group, and 105 patients were classified into the zero-line group, respectively. Demographic data, including age, gender, and the primary tumor side, were similar between the two groups. The duration of surgery in the classical group was longer (2.66 ± 0.68 h) than in the zero-line group (1.40 ± 0.47 h) (p < 0.001). The counts of central compartment lymph node dissection were higher in the zero-line group (5.03 ± 3.02 nodes) than that in the classical group (3.05 ± 2.68 nodes) (p < 0.001). The score of postoperative neck pain was lower in the zero-line group (1.0 ± 0.36) than that in the classical group (3.3 ± 0.54) (p < 0.05). The difference in cosmetic achievement was not statistically significant (p > 0.05). Conclusion: The "zero-line" method for GUA surgery incision design was simple but effective for GUA surgery manipulation and worth promoting.

15.
Polymers (Basel) ; 14(16)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-36015617

RESUMO

As one of the main methods for fabricating microstructured surfaces, micro-injection molding has the advantages of short cycle time, high production efficiency, and the potential for batch manufacturing. However, non-negligible residual stresses inside the molded part could affect the replication quality, dimensions, and physical properties of the microstructure. Therefore, studying the effects of processing parameters on residual stresses is a necessary prerequisite to ensure the successful fabrication of microstructured parts. In this paper, an injection molding simulation model of micro-pillar arrays was developed using molecular dynamics software, and a series of injection molding experiments were conducted. It was found that increasing the mold temperature and melt temperature can reduce the thermal residual stresses and molecular orientation stresses, and effectively improve the uniformity of residual stress distribution. The increase in the packing pressure can make the shear field of flow more intense and increase the molecular orientation stresses, thus making the residual stresses more severe.

16.
PeerJ ; 10: e14118, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262408

RESUMO

Wheat powdery mildew, caused by Blumeria graminis f. sp. tritici (an obligate biotrophic pathogen) is a worldwide threat to wheat production that occurs over a wide geographic area in China. For monitoring genetic variation and virulence structure of Blumeria graminis f. sp. tritici in Liaoning, Heilongjiang, and Sichuan in 2015, 31 wheat lines with known Powdery mildew resistance genes and 2 EST-SSR markers were used to characterize the virulence and genetic diversity. Results indicated that 90% of all isolates were virulent on Pm3c, Pm3e, Pm3f, Pm4a, Pm5, Pm6 (Timgalen), Pm7, Pm16, Pm19, and Pm1 + 2 + 9 and 62.6% to 89.9% of isolates were virulent on Pm3a, Pm3b, Pm3d, Pm4b, Pm6 (Coker747), Pm8, Pm17, Pm20, Pm23, Pm30, Pm4 + 8, Pm5 + 6, Pm4b + mli, Pm2 + mld, Pm4 + 2X, Pm2 + 6. The Pm13 and PmXBD genes were effective against most collected isolates from Liaoning and Heilongjiang Provinces. Only Pm21 exhibited an immune infection response to all isolates. Furthermore, closely related isolates within each region were distinguished by cluster analyses using EST-SSR representing some gene exchanges and genetic relationships between the flora in Northeast China (Liaoning, Heilongjiang) and Sichuan. Only 45% of the isolates tested show a clear correlation between EST-SSR genetic polymorphisms and the frequency of virulence gene data. However, the EST-SSR polymorphism of isolated genes did not correspond to the virulence diversity of isolates in the single-gene lineage identification of hosts.


Assuntos
Ascomicetos , Ascomicetos/genética , Erysiphe/genética , Variação Genética/genética , Virulência/genética , Polimorfismo Genético
17.
JCO Precis Oncol ; 6: e2100267, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35108036

RESUMO

PURPOSE: DNA polymerase epsilon is critical to DNA proofreading and replication. Mutations in POLE have been associated with hypermutated tumors and antitumor response to immune checkpoint inhibitor (ICI) therapy. We present a clinicopathologic analysis of patients with advanced cancers harboring POLE mutations, the pattern of co-occurring mutations, and their response to ICI therapy within the context of mutation pathogenicity. METHODS: We conducted a retrospective analysis of next-generation sequencing data at MD Anderson Cancer Center to identify patient tumors with POLE mutations and their co-occurring mutations. The pathogenicity of each mutation was annotated using InterVar and ClinVar. Differences in therapeutic response to ICI, survival, and co-occurring mutations were reported by POLE pathogenicity status. RESULTS: Four hundred fifty-eight patient tumors with POLE mutations were identified from 14,229 next-generation sequencing reports; 15.0% of POLE mutations were pathogenic, 15.9% benign, and 69.1% variant of unknown significance. Eighty-two patients received either programmed death 1 or programmed death ligand-1 inhibitors as monotherapy or in combination with cytotoxic T-cell lymphocyte-4 inhibitors. Patients with pathogenic POLE mutations had improved clinical benefit rate (82.4% v 30.0%; P = .013), median progression-free survival (15.1 v 2.2 months; P < .001), overall survival (29.5 v 6.8 months; P < .001), and longer treatment duration (median 15.5 v 2.5 months; P < .001) compared to those with benign variants. Progression-free survival and overall survival remained superior when adjusting for number of co-occurring mutations (≥ 10 v < 10) and/or microsatellite instability status (proficient mismatch repair v deficient mismatch repair). The number of comutations was not associated with response to ICI (clinical benefit v progressive disease: median 13 v 11 comutations; P = .18). CONCLUSION: Pathogenic POLE mutations were associated with clinical benefit to ICI therapy. Further studies are warranted to validate POLE mutation as a predictive biomarker of ICI therapy.


Assuntos
DNA Polimerase II/genética , Inibidores de Checkpoint Imunológico , Neoplasias , Proteínas de Ligação a Poli-ADP-Ribose/genética , Biomarcadores , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Mutação , Neoplasias/tratamento farmacológico , Estudos Retrospectivos
18.
Materials (Basel) ; 14(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34576498

RESUMO

A combination of droplet solidification tester and confocal laser scanning microscope was used to simulate subrapid solidification and secondary cooling process pertinent to the strip casting. The IF steel droplet had a delamination structure and the bottom part went through sub-rapid solidification. During secondary cooling, γ/α transformation mechanism belonged to interface-controlled massive transformation and the ferrite grains grew quickly. With the increase of cooling rate, the γ/α transformation temperature decreased and the incubation period and phase transformation duration reduced. The hardness showed a slight increase due to fine-grain strengthening. With coiling temperature increasing from 600 °C to 800 °C, the grain size became larger, precipitates became coarse, and defects in grain were recovered. Consequently, the hardness decreased.

19.
ACS Appl Mater Interfaces ; 13(36): 42813-42821, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34460215

RESUMO

The temperature of outdoor structures, such as automobiles, buildings, and clothing, can be tuned by designing photonic properties. However, particular challenges arise when considering the temperature of an object itself rather than the enclosure in these outdoor structures. We present a double-side photonic thermal (DSPT) system. In the DSPT system, the tunable range of photonic thermal load for heating and cooling functions is calculated by designing the absorption spectra of both sides to adapt to different temperature conditions. These include the proper photonic design of not only the side facing outward but also the inner side and more complex temperature conditions of the object, enclosures, and atmosphere. According to the DSPT mechanisms, we developed a Janus material that can achieve the opposite functions (cooling and heating) with one film by simply flipping the sides of the Janus material, which does not require any additional energy input. The Janus material is designed and fabricated by common materials and a simple multilayer structure, which is attractive for large-scale fabrication. The thermal experiment proved the Janus multilayer could achieve a high temperature in the heating mode and a low temperature in the cooling mode, and the range of the tunable temperature would be wider with stronger sun radiation. The Janus material can passively achieve more efficient temperature control in enclosures while offering both side photonic design comparable to conventional radiative coolers and heaters.

20.
ACS Appl Mater Interfaces ; 13(24): 28369-28377, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34107212

RESUMO

Mn-based layered oxides are very attractive as cathodes for potassium-ion batteries (PIBs) due to their low-cost and environmentally friendly precursors. Their transfer to practical application, however, is inhibited by some issues including consecutive phase transitions, sluggish K+ deintercalation/intercalation, and serious capacity loss. Herein, Mg-Ni co-substituted K1/2Mn5/6Mg1/12Ni1/12O2 is designed as a promising cathode material for PIBs, with suppressed phase transitions that occurred in K1/2MnO2 and improved K+ storage performance. Part of Mg2+ and Ni2+ occupies the K+ layer, playing the role of a "nailed pillar", which restrains metal oxide layer gliding during the K+ (de)intercalation. The "Mg-Ni pinning effect" not only suppresses the phase transitions but also reduces the cell volume variation, leading to the improved cycle performance. Moreover, K1/2Mn5/6Mg1/12Ni1/12O2 has low activation barrier energy for K+ diffusion and high electron conductivity as demonstrated by first-principles calculations, resulting in better rate capability. In addition, K1/2Mn5/6Mg1/12Ni1/12O2 also delivers a higher reversible capacity owing to the participation of the Ni element in electrochemical reactions and the pseudocapacitive contribution. This study provides a basic understanding of structural evolution in layered Mn-based oxides and broadens the strategic design of cathode materials for PIBs.

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