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1.
J Opt Soc Am A Opt Image Sci Vis ; 41(6): 1089-1097, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38856421

RESUMEN

In hyperspectral images, every pixel encompasses continuous spectral information. Compared with traditional colorimeters, using hyperspectral imaging systems (HIS) for fabric color measurement can result in obtaining richer color information. However, measuring fabric colors with liquid crystal tunable filter HIS can lead to challenges related to light consistency. In this paper, we adopted an innovative approach, integrating gradient boosted decision trees with a sliding window algorithm to develop a uniformity calibration model addressing the illumination uniformity issue. To address the consistency issues across various light sources, we further adopted a deep neural network (DNN) model to correct the reflectance measurements under different light sources. Subsequently, this model was merged with the uniformity calibration model to form a light-consistency correction model. Through calibration, we successfully reduced the color difference of the corrected samples from 3.636 to 0.854, an enhancement of 76.51%. This means that after calibration we can achieve consistency in fabric color measurements under nonuniform lighting and different light sources.

2.
Environ Res ; 239(Pt 1): 117198, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37776943

RESUMEN

Fish, as top predators in aquatic ecosystems, play an important role in maintaining the structure and functioning of these ecosystems, making their diversity a topic of great interest. This study focused on the Yangtze River Basin to investigate the fish community structure and diversity using environmental DNA (eDNA) technology. The results showed that a total of 71616 fish operational taxonomic units (OTUs) and 90 fish belonging to 23 families were detected, with the Cyprinidae family being the dominant group, followed by the Cobitidae, Amblycipitidae, etc. Compared to historical traditional morphological fish surveys, the quantity of fish detected using eDNA was relatively low, but the overall distribution pattern of fish communities was generally consistent. The highest fish Shannon-Wiener diversity index in the Yangtze River Basin sites reaches 2.60 with an average value of 1.25. The fish diversity index was higher in the downstream compared to the middle and upstream regions, and there were significant differences among different sampling sites. Significant environmental factors influencing α-diversity included chlorophyll-a, chemical oxygen demand, dissolved oxygen, total nitrogen, and elevation. Non-metric multidimensional scaling (NMDS) analysis revealed significant differences in fish community composition between the upstream and middle/lower reaches of the Yangtze River, while the composition of fish communities in the middle and lower reaches was more similar. Redundancy analysis (RDA) indicated that total organic carbon (TOC) was positively correlated with fish community distribution in the upstream, while water temperature and NO3-N were negatively correlated with fish distribution in the upstream. NH3-N and CODMn were negatively correlated with fish distribution in the middle and downstream regions, indicating a relatively severe water pollution in these areas. Additionally, fish communities in the Yangtze River displayed a typical distance decay pattern.


Asunto(s)
Cyprinidae , ADN Ambiental , Humanos , Animales , Ecosistema , Cyprinidae/genética , Contaminación del Agua , Ríos , Monitoreo del Ambiente , China
3.
Biochem Biophys Res Commun ; 598: 40-46, 2022 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-35151202

RESUMEN

Hepatocytes injury caused by cytolethal distending toxin (CDT) are major events during helicobacter hepaticus (H.hepaticus) infection. Recent study showed that pre-survival autophagy was promoted against CdtB subunit induced DNA damage. In the present study, we demonstrated that inflammatory cytokines IL-6, IL-1ß, TNF-α, IFN-α, IFN-γ expression and STAT phosphorylation were promoted by CdtB. Besides, CdtB decreased cell viability while promote apoptosis in mouse liver (AML12) cells. Especially, apoptotic protein caspase-9, caspase-3 and PARP were activated while the ratio of Bcl-2/Bax was decreased after CdtB treatment. Moreover, apoptosis induced by CdtB was inhibited due to Erk/p38 MAPK signaling pathway suppression performed with SB203580 or U0126. Meanwhile, we found that CdtB increased autophagic marker levels accompanied by Akt/mTOR/P70S6K signaling pathway in a dose dependent manner. To assess the correlation between autophagy and apoptosis induced by H.hepaticus, chloroquine (CQ, 50 µM) was employed to inhibit autophagy. The result showed that inhibition of autophagy with CQ treatment promoted apoptosis induced by CdtB. Altogether, all these results suggest that CdtB triggers apoptosis via MAPK/Erk/p38 signaling pathway in caspase dependent manner, which was prevented by autophagy in AML12 cells. Collectively, our findings provide new insights into the virulence potential of CdtB on the molecular pathogenesis throughout H.hepaticus infection.


Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Toxinas Bacterianas/toxicidad , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Animales , Apoptosis/fisiología , Autofagia/fisiología , Caspasas/genética , Caspasas/metabolismo , Línea Celular , Citocinas/genética , Regulación de la Expresión Génica/efectos de los fármacos , Helicobacter hepaticus/patogenicidad , Hepatocitos/fisiología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/fisiología , Ratones
4.
Dev Sci ; 25(3): e13191, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34775669

RESUMEN

The goal of the present research was to assess whether children's first interaction with a single outgroup member can significantly impact their general attitudes toward the outgroup as a whole. In two preregistered studies, 5- to 6-year-old Chinese children (total N = 147) encountered a Black adult from another country for the very first time, and they played a game together. General attitudes toward the outgroup were assessed using both implicit and explicit measures. In both studies, the interaction resulted in less negative explicit attitudes toward Black people, but more negative implicit attitudes. The results demonstrate for the first time that one encounter with a single outgroup member can impact children's general attitudes toward that group, and that it can have differential effects on implicit and explicit attitudes.


Asunto(s)
Actitud , Población Negra , Adulto , Pueblo Asiatico , Niño , Preescolar , Humanos
5.
Dev Sci ; 25(4): e13221, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34942036

RESUMEN

Current understanding of how culture relates to the development of children's gender-related peer preferences is limited. To investigate the role of societal acceptance of gender nonconformity, this study compared children from China and Thailand. Unlike China and other cultures where the conceptualization of gender as binary is broadly accepted, individuals who identify as a nonbinary "third" sex/gender have been highly visible and tolerated in Thai society for at least several decades. Chinese and Thai 4- to 9-year-olds (N = 458) viewed vignettes of four hypothetical peers who varied on gender (i.e., boy vs. girl) and gender-typed toy play behavior (i.e., masculine vs. feminine), and were asked to give a friendship preference rating for each peer. Chinese, compared with Thai, children evidenced gender-related peer preferences that emerged earlier, remained more stable across age groups, and were relatively more biased against gender-nonconforming behavior. The only cultural similarity was in children's preference for peers who were of the same gender and/or displayed same-gender-typed behavior. Thus, while preference for peers who are of the same gender and/or display same-gender-typed behavior is common among children across cultures, the developmental onset and course of these preferences vary by culture. Moreover, societal acceptance of gender nonconformity might be key to limiting children's bias against gender-nonconforming peers.


Asunto(s)
Identidad de Género , Grupo Paritario , Niño , China , Femenino , Humanos , Masculino , Tailandia
6.
Arch Sex Behav ; 50(3): 807-820, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33169294

RESUMEN

From a young age, children's peer appraisals are influenced by the social categories to which peers belong based on factors such as race and gender. To date, research regarding the manner in which race- and gender-related factors might interact to influence these appraisals has been limited. The present study employed an experimental vignette paradigm to investigate the relative influences of target peers' race, gender, and gender-typed behavior toward 4- to 6-year-old Chinese children's (N = 119, 62 girls, 57 boys) peer appraisals. Appraisals were assessed via (1) a rating scale measuring children's interest in being friends with a range of hypothetical target peers varying in race, gender, and gender-typed behavior, and (2) a forced-choice rank-order task in which children indicated their preferences for four hypothetical target peers who varied from themselves on either race, gender, or gender-typed behavior, or were similar to themselves on all three traits. There was little evidence to suggest children's rank-ordered peer preferences in relation to race were influenced by whether the other-race presented was White (preferred relatively more) or Black (preferred relatively less). In contrast, gender-related factors (i.e., rater gender, target gender, target gender-typed behavior) had more robust influences on peer preferences for both outcome measures. Gender-conforming peers were preferred over gender-nonconforming peers, and target boys displaying feminine behavior were less preferred than target girls displaying masculine behavior. The results help characterize cross-cultural (in)consistencies in children's social preferences in relation to peers' race and gender.


Asunto(s)
Amigos/psicología , Grupos Raciales/psicología , Conducta Social , Niño , Preescolar , Femenino , Identidad de Género , Humanos , Masculino
7.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(6): 593-598, 2021 Jun.
Artículo en Zh | MEDLINE | ID: mdl-34130781

RESUMEN

OBJECTIVE: To evaluate the clinical features of preterm infants with a birth weight less than 1 500 g undergoing different intensities of resuscitation. METHODS: A retrospective analysis was performed for the preterm infants with a birth weight less than 1 500 g and a gestational age less than 32 weeks who were treated in the neonatal intensive care unit of 20 hospitals in Jiangsu, China from January 2018 to December 2019. According to the intensity of resuscitation in the delivery room, the infants were divided into three groups:non-tracheal intubation (n=1 184), tracheal intubation (n=166), and extensive cardiopulmonary resuscitation (ECPR; n=116). The three groups were compared in terms of general information and clinical outcomes. RESULTS: Compared with the non-tracheal intubation group, the tracheal intubation and ECPR groups had significantly lower rates of cesarean section and use of antenatal corticosteroid (P < 0.05). As the intensity of resuscitation increased, the Apgar scores at 1 minute and 5 minutes gradually decreased (P < 0.05), and the proportion of infants with Apgar scores of 0 to 3 at 1 minute and 5 minutes gradually increased (P < 0.05). Compared with the non-tracheal intubation group, the tracheal intubation and ECPR groups had significantly higher mortality rate and incidence rates of moderate-severe bronchopulmonary dysplasia and serious complications (P < 0.05). The incidence rates of grade Ⅲ-Ⅳ intracranial hemorrhage and retinopathy of prematurity (stage Ⅲ or above) in the tracheal intubation group were significantly higher than those in the non-tracheal intubation group (P < 0.05). CONCLUSIONS: For preterm infants with a birth weight less than 1 500 g, the higher intensity of resuscitation in the delivery room is related to lower rate of antenatal corticosteroid therapy, lower gestational age, and lower birth weight. The infants undergoing tracheal intubation or ECRP in the delivery room have an increased incidence rate of adverse clinical outcomes. This suggests that it is important to improve the quality of perinatal management and delivery room resuscitation to improve the prognosis of the infants.


Asunto(s)
Cesárea , Recien Nacido Prematuro , Peso al Nacer , China , Femenino , Edad Gestacional , Humanos , Lactante , Recién Nacido , Embarazo , Estudios Retrospectivos
8.
J Exp Child Psychol ; 198: 104884, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32645522

RESUMEN

The early emergence of racial biases points to the urgent need to understand how interpersonal experiences might shape them. We examined whether interpersonal movement shapes racial biases among 4- to 6-year-old Chinese children who had no prior contact with Black people. In Experiment 1 (N = 134), children played a musical game, moving either in or out of synchrony with a Chinese or Black adult. In Experiment 2 (N = 30), children were merely exposed to a Black adult. Across the two experiments, we found that synchronous movement increased children's feeling of social closeness toward their movement partner to a greater extent than asynchronous movement regardless of the partner's race. After moving in or out of synchrony with the Chinese adult, synchrony selectively increased children's explicit positive pro-own-race bias. However, after moving in or out of synchrony with the Black adult, both movement styles reduced explicit anti-other-race bias. Experiment 2 ruled out mere exposure to an other-race person as a driving factor for these effects. Our results suggest that musical engagement may be a promising intervention for reducing negative intergroup biases.


Asunto(s)
Desarrollo Infantil , Música , Racismo , Interacción Social , Percepción Social , Niño , Preescolar , Femenino , Humanos , Masculino , Factores de Tiempo
9.
Child Dev ; 90(3): e290-e305, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-29023649

RESUMEN

This study tracked the long-term effect of perceptual individuation training on reducing 5-year-old Chinese children's (N = 95, Mage  = 5.64 years) implicit pro-Asian/anti-Black racial bias. Initial training to individuate other-race Black faces, followed by supplementary training occurring 1 week later, resulted in a long-term reduction of pro-Asian/anti-Black bias (70 days). In contrast, training Chinese children to recognize White or Asian faces had no effect on pro-Asian/anti-Black bias. Theoretically, the finding that individuation training can have a long-term effect on reducing implicit racial bias in preschoolers suggests that a developmentally early causal linkage between perceptual and social processing of faces is not a transitory phenomenon. Practically, the data point to an effective intervention method for reducing implicit racism in young children.


Asunto(s)
Individualismo , Racismo/etnología , Negro o Afroamericano , Pueblo Asiatico , Preescolar , China/etnología , Discriminación en Psicología/fisiología , Reconocimiento Facial , Femenino , Humanos , Masculino , Satisfacción Personal , Racismo/psicología , Percepción Social , Población Blanca
10.
Child Dev ; 90(1): 162-179, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-28605007

RESUMEN

This research investigated the relation between racial categorization and implicit racial bias in majority and minority children. Chinese and Indian 3- to 7-year-olds from Singapore (N = 158) categorized Chinese and Indian faces by race and had their implicit and explicit racial biases measured. Majority Chinese children, but not minority Indian children, showed implicit bias favoring own race. Regardless of ethnicity, children's racial categorization performance correlated positively with implicit racial bias. Also, Chinese children, but not Indian children, displayed explicit bias favoring own race. Furthermore, children's explicit bias was unrelated to racial categorization performance and implicit bias. The findings support a perceptual-social linkage in the emergence of implicit racial bias and have implications for designing programs to promote interracial harmony.


Asunto(s)
Etnicidad , Grupos Minoritarios , Racismo/etnología , Percepción Social , Niño , Preescolar , China/etnología , Femenino , Humanos , India/etnología , Masculino , Singapur/etnología
11.
Cancer Cell Int ; 18: 200, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30534001

RESUMEN

BACKGROUND: Apoptosis and autophagy are known to play important roles in cancer development. It has been reported that HVJ-E induces apoptosis in cancer cells, thereby inhibiting the development of tumors. To define the mechanism by which HVJ-E induces cell death, we examined whether HVJ-E activates autophagic and apoptotic signaling pathways in HeLa cells. METHODS: Cells were treated with chloroquine (CQ) and rapamycin to determine whether autophagy is involved in HVJ-E-induced apoptosis. Treatment with the ERK inhibitor, U0126, was used to determine whether autophagy and apoptosis are mediated by the ERK pathway. Activators of the PI3K/Akt/mTOR/p70S6K pathway, 740 Y-P and SC79, were used to characterize its role in HVJ-E-induced autophagy. siRNA against Atg3 was used to knock down the protein and determine whether it plays a role in HVJ-E-induced apoptosis in HeLa cells. RESULTS: We found that HVJ-E infection inhibited cell viability and induced apoptosis through the mitochondrial pathway, as evidenced by the expression of caspase proteins. This process was promoted by rapamycin treatment and inhibited by CQ treatment. HVJ-E-induced autophagy was further blocked by 740 Y-P, SC79, and U0126, indicating that both the ERK- and the PI3K/Akt/mTOR/p70S6K-pathways were involved. Finally, autophagy-mediated apoptosis induced by HVJ-E was inhibited by siRNA-mediated Atg3 knockdown. CONCLUSION: In HeLa cells, HVJ-E infection triggered autophagy through the PI3K/Akt/mTOR/p70S6K pathway in an ERK1/2-dependent manner, and the induction of autophagy promoted apoptosis in an Atg3-dependent manner.

12.
Med Sci Monit ; 24: 8583-8591, 2018 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-30481165

RESUMEN

BACKGROUND UV-related skin disease such as actinic keratosis is a major concern in public health. In view of the cell injury induced by UVB, Klotho protein it is an ideal therapy to eliminate UVB-induced cell damages and the associated signaling pathways. MATERIAL AND METHODS To gain insights into the potential role of Klotho and the underlying molecular mechanism, we constructed a Klotho-overexpress HaCaT cell line and assessed the protection against UVB insults. The effects of exposure to UVB radiation on the human keratinocyte HaCaT cells, including cell growth, apoptosis, and changes of selected biomarkers, were measured by CCK-8, flow cytometry, Quantitative real-time PCR, and Western blot analysis. RESULTS We found that enhanced NF-κB activity was accompanied by decreased expression of the anti-aging protein Klotho upon UVB stimulation, which was further confirmed with in vivo experiments. Overexpression of Klotho was able to considerably alleviate the UVB-induced damages to cells and reversed the UVB-caused biomarker changes to a great extent, which was comparable to the effects of administration of NF-κB inhibitor PDTC, suggesting the inhibition of nuclear translocation and DNA-binding activity of NF-κB. Furthermore, Klotho overexpression was proved to decrease the nuclear expression of NF-κB as much as the treatment with PDTC, which provides support for the direct regulation of NF-κB by Klotho. CONCLUSIONS Collectively, our work provides new insight into the potential role of Klotho in the context of UVB-induced injuries in human keratinocytes, as well as providing the basis for future study of new therapies against UV-related skin disease.


Asunto(s)
Glucuronidasa/metabolismo , Queratinocitos/metabolismo , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Humanos , Queratinocitos/fisiología , Proteínas Klotho , FN-kappa B/metabolismo , FN-kappa B/efectos de la radiación , Sustancias Protectoras/farmacología , Protectores contra Radiación/farmacología , Transducción de Señal/efectos de los fármacos , Rayos Ultravioleta/efectos adversos
13.
Biomed Environ Sci ; 31(4): 280-289, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29773091

RESUMEN

OBJECTIVE: The current study aims to investigate the effect of Hemagglutinating virus of Japan envelope (HVJ-E) on induction of apoptosis and autophagy in human prostate cancer PC3 cells, and the underlying mechanisms. METHODS: PC3 cells were treated with HVJ-E at various multiplicity of infection (MOI), and the generated reactive oxygen species (ROS), cell viability, apoptosis, and autophagy were detected, respectively. Next, the role of ROS played in the regulation of HVJ-E-induced apoptosis and autuphagy in PC3 cells were analysed. In the end, the relationship between HVJ-E-induced apoptosis and autuophagy was investigated by using rapamycin and chloroquine. RESULTS: Flow cytometry assay revealed that HVJ-E treatment induced dose-dependent apoptosis and that the JNK and p38 MAPK signaling pathways were involved in HVJ-E-induced apoptosis in PC3 cells. In addition, HVJ-E was able to induce autophagy in PC3 cells via the class III PI3K/beclin-1 pathway. The data also implyed that HVJ-E-triggered autophagy and apoptosis were ROS dependent. When ROS was blocked with N-acetylcysteine (NAC), HVJ-E-induced LC3-II conversion and apoptosis were reversed. Interestingly, HVJ-E-induced apoptosis was significantly increased by an inducer of autophagy, rapamycin pretreatment, both in vitro and in vivo. CONCLUSION: HVJ-E exerts anticancer effects via autophagic cell death in prostate cancer cells.


Asunto(s)
Apoptosis/fisiología , Autofagia/fisiología , Neoplasias de la Próstata/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Virus Sendai/inmunología , Inactivación de Virus , Línea Celular Tumoral , Supervivencia Celular , Humanos , Masculino , Viroterapia Oncolítica , Virus Sendai/fisiología
14.
Zhongguo Dang Dai Er Ke Za Zhi ; 19(7): 812-815, 2017 Jul.
Artículo en Zh | MEDLINE | ID: mdl-28697837

RESUMEN

The study reports a female neonate with a gestational age of 29+2 weeks and a birth weight of 1 210 g. Ten minutes after birth, the neonate was admitted to the hospital due to shortness of breath. Several days after birth, the neonate presented with hyperglycemia, polyuria, and poor weight gain, accompanied by azotemia, hypochloremic metabolic alkalosis, hypokalemia, and hyponatremia. Laboratory examinations showed elevated levels of aldosterone, renin, and angiotensin II. Gene detection revealed SLC12A1 gene mutation. Neonatal Bartter syndrome was thus confirmed. The neonate was treated with sodium and potassium supplements, and was followed up for 8 months. During the follow-up, the mental and neural development of the neonate was almost normal at the corrected age, and regular reexaminations showed slight metabolic alkalosis and almost normal electrolyte levels. For the neonates who have the symptoms of unexplainable polyurine and electrolyte disorders, it is important to examine the levels of aldosterone, renin and angiotensin. A definite diagnosis of neonatal Bartter syndrome can be made based on the presence of SLC12A1 gene mutation.


Asunto(s)
Acidosis/etiología , Síndrome de Bartter/etiología , Hipopotasemia/etiología , Aumento de Peso , Síndrome de Bartter/terapia , Femenino , Humanos , Recién Nacido , Recurrencia
15.
Dev Sci ; 19(2): 275-83, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25872952

RESUMEN

The present study examined whether having a positive reputation to maintain makes young children less likely to cheat. Cheating was assessed through a temptation resistance paradigm in which participants were instructed not to cheat in a guessing game. Across three studies (total N = 361), preschool-aged participants were randomly assigned to either a reputation condition, in which an experimenter told them that she had learned of their positive reputation from classmates, or to a control condition in which they received no such information. By age 5, children in the reputation condition cheated less often than those in the control condition even though nobody was watching and choosing not to cheat conflicted with their personal interest. These findings are the first to show that informing children that they have a positive reputation to maintain can influence their moral behavior.


Asunto(s)
Fraude/psicología , Deseabilidad Social , Niño , Desarrollo Infantil , Preescolar , Femenino , Humanos , Masculino , Distribución Aleatoria , Conducta Social
17.
Child Dev ; 87(1): 285-96, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26435128

RESUMEN

This research used an Implicit Racial Bias Test to investigate implicit racial biases among 3- to 5-year-olds and adult participants in China (N = 213) and Cameroon (N = 257). In both cultures, participants displayed high levels of racial biases that remained stable between 3 and 5 years of age. Unlike adults, young children's implicit racial biases were unaffected by the social status of the other-race groups. Also, unlike adults, young children displayed overt explicit racial biases, and these biases were dissociated from their implicit biases. The results provide strong evidence for the early emergence of implicit racial biases and point to the need to reduce them in early childhood.


Asunto(s)
Desarrollo Infantil , Racismo/etnología , Adolescente , Adulto , Camerún/etnología , Preescolar , China/etnología , Femenino , Humanos , Masculino , Adulto Joven
18.
J Exp Child Psychol ; 139: 242-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26074407

RESUMEN

Widespread cheating can undermine rules that are necessary for maintaining social order. Preventing cheating can be a challenge, especially with regard to children, who as a result of their limited executive function skills may have particular difficulty with resisting temptation to cheat. We examined one approach designed to help children resist this temptation: eliciting a verbal commitment to not cheat. We tested 4- to 7-year-olds (total N = 330) and found that starting at 5 years of age, a verbal commitment to not cheat led to a substantial reduction in cheating. The results suggest that verbal commitments can be used to help children overcome temptations and comply with rules.


Asunto(s)
Control de la Conducta/psicología , Decepción , Motivación/fisiología , Niño , Preescolar , Función Ejecutiva/fisiología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas
19.
Materials (Basel) ; 16(16)2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37629825

RESUMEN

Rolling treatments have been identified as a promising fabrication and deformation processing technique for graphene/metal composites with high performance. However, it is still a challenge to choose appropriate rolling parameters to achieve high strength, ductility and electrical conductivity of the composite simultaneously. In this study, graphene/Cu composites were prepared with an in situ growth method and rolling treatment. The effects of rolling deformation and temperature on the microstructural evolution of graphene and Cu grains, interface bonding between graphene and the matrix, mechanical and electrical properties were systemically investigated. The cold-rolled composite with 85% deformation displayed a maximum ultimate strength of 548 MPa, a high elongation of 8.8% and a good electrical conductivity of 86.2% IACS. This is attributed to oriented graphene arrangement and matrix grain refinement. Our research provides a comprehensive understanding for the rolling behavior of graphene/Cu composites, and can promote the development of graphene-based composites with high performance.

20.
Materials (Basel) ; 16(13)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37445192

RESUMEN

Three-dimensional porous network encapsulation strategy is an effective means to obtain composite phase-change materials (PCMs) with high heat storage capacity and enhanced thermal conductivity. Herein, macroporous reduced graphene oxide (rGO) aerogels with adjustable pore size are prepared by the emulsion template method and hydrothermal reduction process. Further, the shape-stabilized rGO-aerogel-based composite PCMs are constructed after the combination of 3D porous rGO supports and paraffin wax (PW) through vacuum melting infiltration. By regulating the pore structure of the rGO aerogel network, the rGO-based composite PCMs achieve excellent energy storage properties with a phase-change enthalpy of 179.94 J/g for the loading amount of 95.61 wt% and an obvious enhancement in thermal conductivity of 0.412 W/m-1·K-1, which is 54.89% higher than pristine PW and enduring thermal cycling stability. The obtained macroporous rGO-aerogel-based composite PCMs with high thermal storage and heat transfer performance effectively broaden the application of PCMs in the field of thermal energy storage.

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