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1.
Nat Commun ; 15(1): 5305, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38906873

RESUMEN

Direct hydrogen production from inexhaustible seawater using abundant offshore wind power offers a promising pathway for achieving a sustainable energy industry and fuel economy. Various direct seawater electrolysis methods have been demonstrated to be effective at the laboratory scale. However, larger-scale in situ demonstrations that are completely free of corrosion and side reactions in fluctuating oceans are lacking. Here, fluctuating conditions of the ocean were considered for the first time, and seawater electrolysis in wave motion environment was achieved. We present the successful scaling of a floating seawater electrolysis system that employed wind power in Xinghua Bay and the integration of a 1.2 Nm3 h-1-scale pilot system. Stable electrolysis operation was achieved for over 240 h with an electrolytic energy consumption of 5 kWh Nm-3 H2 and a high purity (>99.9%) of hydrogen under fluctuating ocean conditions (0~0.9 m wave height, 0~15 m s-1 wind speed), which is comparable to that during onshore water electrolysis. The concentration of impurity ions in the electrolyte was low and stable over a long period of time under complex and changing scenarios. We identified the technological challenges and performances of the key system components and examined the future outlook for this emerging technology.

2.
Front Psychol ; 15: 1288644, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38577114

RESUMEN

Whether parental educational expectations for adolescents serve as a source of motivation or stress depends on the extent to which adolescents hold expectations for themselves. Previous research on the discrepancies between parental and adolescent educational expectations and their impact on learning engagement has been limited by traditional statistical tests, and lacking an examination of the internal mediating mechanism of parent-child relational quality from both parental and adolescent perspectives. This cross-sectional study, utilizing a multi-informant design, examined the association between discrepancies in parents' and adolescents' reports of expectations, and adolescents' study engagement, as well as the mediating role of parent-child relational qualities perceived by both parties. The sample for this study consisted of 455 adolescents and their parents from 10 classes in a junior high school in Wuhan, Hubei Province, China. The adolescents had an average age of 12.8 years, and 51.6% of them were boys. Both parents and adolescents reported on their expectations and perceived relational quality, while adolescents also filled out questionnaires assessing their learning engagement. Data were analyzed using polynomial regressions with response surface analysis. The results revealed that when adolescents reported high expectations, regardless of whether their parents reported high or low expectations, adolescents reported satisfied relationships and high learning engagement. In contrast, parents reported satisfied relationships when both parties reported high expectations, or when parents reported higher expectations than adolescents. Lastly, the association between discrepancies in expectations and learning engagement was significantly mediated by adolescent-reported relationships but not parent-reported ones. These findings highlight the importance of considering multiple perspectives when studying the association between expectations and adolescent study engagement. This research advances our comprehension of the dynamics between parent-adolescent educational expectation discrepancies and adolescent learning engagement, offering insights for more nuanced and effective parenting strategies tailored to foster optimal educational outcomes.

3.
Acta Psychol (Amst) ; 240: 104039, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37748326

RESUMEN

Drawing is regarded as a promising strategy for children's learning, which has greatly been supported by research using science texts as learning materials. To shed light on the benefit of drawing on children's text-based learning in humanities, two classes of 86 grade 5 children were required to learn an ancient Chinese poem in an actual classroom setting, either by drawing a visual picture illustrating the poem or by reading repeatedly at their own pace as usual. Data analyses were conducted using (generalized) linear mixed-effects models. The results indicated that children who were allowed to generate a drawing during learning showed better learning performance of the entire poem than children who were allowed to read repeatedly regarding the delayed posttest rather than the immediate posttest. Besides, children in the drawing group reported a higher level of learning motivation than those in the reading group. We argue that the generative drawing effect can be tentatively extended to ancient Chinese poetry education.


Asunto(s)
Aprendizaje , Niño , Humanos , Motivación , Lectura , Poesía como Asunto , Arte
4.
Front Public Health ; 11: 1249742, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37637794

RESUMEN

As the growing population of individuals residing or working in deep underground spaces for prolonged periods, it has become imperative to understand the influence of factors in the deep underground environment (DUGE) on living systems. Heping Xie has conceptualized the concept of deep underground medicine to identify factors in the DUGE that can have either detrimental or beneficial effects on human health. Over the past few years, an increasing number of studies have explored the molecular mechanisms that underlie the biological impacts of factors in the DUGE on model organisms and humans. Here, we present a summary of the present landscape of biological and medical research conducted in deep underground laboratories and propose promising avenues for future investigations in this field. Most research demonstrates that low background radiation can trigger a stress response and affect the growth, organelles, oxidative stress, defense capacity, and metabolism of cells. Studies show that residing and/or working in the DUGE has detrimental effects on human health. Employees working in deep mines suffer from intense discomfort caused by high temperature and humidity, which increase with depth, and experience fatigue and sleep disturbance. The negative impacts of the DUGE on human health may be induced by changes in the metabolism of specific amino acids; however, the cellular pathways remain to be elucidated. Biological and medical research must continue in deep underground laboratories and mines to guarantee the safe probing of uncharted depths as humans utilize the deep underground space.


Asunto(s)
Investigación Biomédica , Estrés Fisiológico , Humanos , Ansiedad , Fatiga , Humedad , Mineros
5.
Plant Physiol ; 193(1): 519-536, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37224514

RESUMEN

Citrus, 1 of the largest fruit crops with global economic and nutritional importance, contains fruit known as hesperidium with unique morphological types. Citrus fruit ripening is accompanied by chlorophyll degradation and carotenoid biosynthesis, which are indispensably linked to color formation and the external appearance of citrus fruits. However, the transcriptional coordination of these metabolites during citrus fruit ripening remains unknown. Here, we identified the MADS-box transcription factor CsMADS3 in Citrus hesperidium that coordinates chlorophyll and carotenoid pools during fruit ripening. CsMADS3 is a nucleus-localized transcriptional activator, and its expression is induced during fruit development and coloration. Overexpression of CsMADS3 in citrus calli, tomato (Solanum lycopersicum), and citrus fruits enhanced carotenoid biosynthesis and upregulated carotenogenic genes while accelerating chlorophyll degradation and upregulating chlorophyll degradation genes. Conversely, the interference of CsMADS3 expression in citrus calli and fruits inhibited carotenoid biosynthesis and chlorophyll degradation and downregulated the transcription of related genes. Further assays confirmed that CsMADS3 directly binds and activates the promoters of phytoene synthase 1 (CsPSY1) and chromoplast-specific lycopene ß-cyclase (CsLCYb2), 2 key genes in the carotenoid biosynthetic pathway, and STAY-GREEN (CsSGR), a critical chlorophyll degradation gene, which explained the expression alterations of CsPSY1, CsLCYb2, and CsSGR in the above transgenic lines. These findings reveal the transcriptional coordination of chlorophyll and carotenoid pools in the unique hesperidium of Citrus and may contribute to citrus crop improvement.


Asunto(s)
Citrus , Solanum lycopersicum , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Citrus/genética , Citrus/metabolismo , Clorofila/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas , Carotenoides/metabolismo , Solanum lycopersicum/genética , Frutas/metabolismo
6.
Nature ; 612(7941): 673-678, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36450987

RESUMEN

Electrochemical saline water electrolysis using renewable energy as input is a highly desirable and sustainable method for the mass production of green hydrogen1-7; however, its practical viability is seriously challenged by insufficient durability because of the electrode side reactions and corrosion issues arising from the complex components of seawater. Although catalyst engineering using polyanion coatings to suppress corrosion by chloride ions or creating highly selective electrocatalysts has been extensively exploited with modest success, it is still far from satisfactory for practical applications8-14. Indirect seawater splitting by using a pre-desalination process can avoid side-reaction and corrosion problems15-21, but it requires additional energy input, making it economically less attractive. In addition, the independent bulky desalination system makes seawater electrolysis systems less flexible in terms of size. Here we propose a direct seawater electrolysis method for hydrogen production that radically addresses the side-reaction and corrosion problems. A demonstration system was stably operated at a current density of 250 milliamperes per square centimetre for over 3,200 hours under practical application conditions without failure. This strategy realizes efficient, size-flexible and scalable direct seawater electrolysis in a way similar to freshwater splitting without a notable increase in operation cost, and has high potential for practical application. Importantly, this configuration and mechanism promises further applications in simultaneous water-based effluent treatment and resource recovery and hydrogen generation in one step.

7.
Appl Bionics Biomech ; 2022: 2693500, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36133746

RESUMEN

Recruitment maneuver (RM) has become a routine supplementary maneuver for clinical rescue of severe ARDS with low tidal volume/pressure-limited mechanical ventilation. Recruitment of patients with ARDS mechanical ventilation can improve the lung compliance, promote the opening of collapsed alveoli, improve the ratio of ventilation to blood flow, reduce dead space, reduce shunt flow, and improve oxygenation function. In this paper, the patients were divided into lung recruitment group and conventional treatment group by the random number permutation table method. When the patient's percutaneous oxygen saturation is less than or equal to 88%, the partial pressure of oxygen in the arterial blood gas is less than or equal to 55 mmHg, or the ventilator tube is disconnected during sputum suction or other accidents, a CPAP × 60 - second lung recruitment maneuver is required. Then adjust the ventilator parameters in the same way. In the process of lung recruitment, the changes in invasive continuous arterial blood pressure will also be observed. If the blood pressure dropped to ≤90/60 mmHg, one recruitment maneuver was terminated in advance. And both groups of patients used the Dräger- or PB840-imported multifunctional ventilator. The treatment of primary disease and predisposing factors, fluid management strategies, antibiotics and glucocorticoids, nutrition, and metabolic support in the two groups of patients in the study were the same. The PaO2/FiO2 value improved by 51% 10 minutes after recruitment, and the median increased from 111 (IQR, 73-265) before recruitment to 170 (IQR, 102-340) (P < 0.01), the improvement of PaO2/FiO2 at 4 hours after recruitment and 12 hours after recruitment was 78% (P < 0.05) and 39% (P < 0.01), respectively, and the median PaO2/FiO2 at 4 hours after recruitment was 198 (IQR, 116-256). The median PaO2/FiO2 became 155 (IQR, 127-235) 12 hours after recruitment. Recruitment can reduce the accumulation of neutrophils in lung tissue, reduce the release of inflammatory factors, reduce pulmonary edema, and reduce pathological damage.

8.
Ann Transl Med ; 10(15): 824, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36035002

RESUMEN

Background: Preliminary research has shown an inhibited growth rate of well-differentiated laryngeal squamous cell carcinoma cells (FD-LSC-1) in below-background radiation (BBR), but how the cells respond to this environmental stress and the potential mechanisms are yet unknown. The current study aimed to reveal the molecular differences in cells grown under BBR conditions and normal radiation at the transcriptional level. Methods: The expression profiles between FD-LSC-1 cells grown in a deep underground laboratory and above ground laboratory collected on day 4 were investigated by whole-transcriptome analysis, including messenger RNAs (mRNAs), long non-coding RNAs (lncRNAs), circular RNAs (circRNAs), and microRNAs (miRNAs). Functional analyses of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were then implemented for differentially expressed (DE) mRNAs and target genes of lncRNAs and circRNAs. Co-expression levels and the Bayesian network of DE genes were subsequently constructed, and the reliability of expression patterns were validated by quantitative real-time polymerase chain reaction (PCR). Results: The study identified a total of 671 mRNAs, 286 lncRNAs, 489 circRNAs, and 6 miRNAs as significantly expressed in response to the environmental stress. The GO annotations regarding the biological processes category were mainly biological regulation, metabolic process, response to stimulus, cell cycle, and modification process. The KEGG enrichment analysis indicated that TGF-ß and Hippo signaling played a crucial role in the transcriptional regulation of FD-LSC-1 cell growth under background radiation. Further network construction suggested that the enriched KEGG pathways affected this process by regulating cell proliferation-related genes including SMAD, SMAD7, CDH1, EGR1, and BMP2. Conclusions: Below-background radiation can lead to transcriptional changes in FD-LSC-1 cells cultured in the deep underground. The inhibitory growth effect is associated with multiple biological processes as well as canonical pathways of proliferation.

9.
Planta ; 255(4): 72, 2022 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-35218440

RESUMEN

MAIN CONCLUSION: Peptide-receptor complexes activate distinct downstream regulatory networks to mediate plant adaptions to abiotic environmental stress. Plants are constantly exposed to various adverse environmental factors; thus they must adjust their growth accordingly. Plants recruit small secretory peptides to adapt to these detrimental environments. These small peptides, which are perceived by their corresponding receptors and/or co-receptors, act as local- or long-distance mobile signaling molecules to establish cell-to-cell regulatory networks, resulting in optimal cellular and physiological outputs. In this review, we highlight recent advances on the regulatory role of small peptides in plant abiotic responses and nutrients signaling.


Asunto(s)
Plantas , Señales de Clasificación de Proteína , Adaptación Fisiológica , Transducción de Señal , Estrés Fisiológico
10.
Front Genet ; 12: 698046, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34603371

RESUMEN

Background: Prior studies have shown that the proliferation of V79 lung fibroblast cells could be inhibited by low background radiation (LBR) in deep underground laboratory (DUGL). In the current study, we revealed further molecular changes by performing whole transcriptome analysis on the expression profiles of long non-coding RNA (lncRNA), messenger RNA (mRNA), circular RNA (circRNA) and microRNA (miRNA) in V79 cells cultured for two days in a DUGL. Methods: Whole transcriptome analysis including lncRNA, mRNAs, circ RNA and miRNA was performed in V79 cells cultured for two days in DUGL and above ground laboratory (AGL), respectively. The differentially expressed (DE) lncRNA, mRNA, circRNA, and miRNA in V79 cells were identified by the comparison between DUGL and AGL groups. Quantitative real-time polymerase chain reaction(qRT-PCR)was conducted to verify the selected RNA sequencings. Then, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway was analyzed for the DE mRNAs which enabled to predict target genes of lncRNA and host genes of circRNA. Results: With |log2(Fold-change)| ≥ 1.0 and p < 0.05, a total of 1257 mRNAs (353 mRNAs up-regulated, 904 mRNAs down-regulated), 866 lncRNAs (145 lncRNAs up-regulated, 721 lncRNAs down-regulated), and 474 circRNAs (247 circRNAs up-regulated, 227 circRNAs down-regulated) were significantly altered between the two groups. There was no significant difference in miRNA between the two groups. The altered RNA profiles were mainly discovered in lncRNAs, mRNAs and circRNAs. DE RNAs were involved in many pathways including ECM-RI, PI3K-Akt signaling, RNA transport and the cell cycle under the LBR stress of the deep underground environment. Conclusion: Taken together, these results suggest that the LBR in the DUGL could induce transcriptional repression, thus reducing metabolic process and reprogramming the overall gene expression profile in V79 cells.

11.
ACS Appl Mater Interfaces ; 13(39): 47081-47089, 2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34565145

RESUMEN

In thermoelectrics, the material's performance stems from a delicate tradeoff between atomic order and disorder. Generally, dopants and thus atomic disorder are indispensable for optimizing the carrier concentration and scatter short-wavelength heat-carrying phonons. However, the strong disorder has been perceived as detrimental to the semiconductor's electrical conductivity owing to the deteriorated carrier mobility. Here, we report the sustainable role of strong atomic disorder in suppressing the detrimental phase transition and enhancing the thermoelectric performance in GeTe. We found that AgSnSe2 and Sb co-alloying eliminates the unfavorable phase transition due to the high configurational entropy and achieve the cubic Ge1-x-ySbyTe1-x(AgSnSe2)x solid solutions with cationic and anionic site disorder. Though AgSnSe2 substitution drives the carrier mean free path toward the Ioffe-Regel limit and minimizes the carrier mobility, the increased carrier concentration could render a decent electrical conductivity, affording enough phase room for further performance optimization. Given the lowermost carrier mean free path, further Sb alloying on Ge sites was implemented to progressively optimize the carrier concentration and enhance the density-of-state effective mass, thereby substantially enhancing the Seebeck coefficient. In addition, the high density of nanoscale strain clusters induced by strong atomic disorders significantly restrains the lattice thermal conductivity. As a result, a state-of-the-art zT ≈ 1.54 at 773 K was attained in cubic Ge0.58Sb0.22Te0.8(AgSnSe2)0.2. These results demonstrate that the strong atomic disorder at the high entropy scale is a previously underheeded but promising approach in thermoelectric material research, especially for the numerous low carrier mobility materials.

12.
Adv Sci (Weinh) ; 8(12): 2100220, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34194947

RESUMEN

The configurational entropy is an emerging descriptor in the functional materials genome. In thermoelectric materials, the configurational entropy helps tune the delicate trade-off between carrier mobility and lattice thermal conductivity, as well as the structural phase transition, if any. Taking GeTe as an example, low-entropy GeTe generally have high carrier mobility and distinguished zT > 2, but the rhombohedral-cubic phase transition restricts the applications. In contrast, despite cubic structure and ultralow lattice thermal conductivity, the degraded carrier mobility leads to a low zT in high-entropy GeTe. Herein, medium-entropy alloying is implemented to suppress the phase transition and achieve the cubic GeTe with ultralow lattice thermal conductivity yet decent carrier mobility. In addition, co-alloying of (Mn, Pb, Sb, Cd) facilitates multivalence bands convergence and band flattening, thereby yielding good Seebeck coefficients and compensating for decreased carrier mobility. For the first time, a state-of-the-art zT of 2.1 at 873 K and average zT ave of 1.3 between 300 and 873 K are attained in cubic phased Ge0.63Mn0.15Pb0.1Sb0.06Cd0.06Te. Moreover, a record-high Vickers hardness of 270 is attained. These results not only promote GeTe materials for practical applications, but also present a breakthrough in the burgeoning field of entropy engineering.

13.
Front Public Health ; 8: 584964, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33194991

RESUMEN

Background: There has been a considerable concern about cancer induction in response to radiation exposure. However, only a limited number of studies have focused on the biological effects of below-background radiation (BBR) in deep underground environments. To improve our understanding of the effects of BBR on cancer, we studied its biological impact on well-differentiated laryngeal squamous cell carcinoma cells (FD-LSC-1) in a deep underground laboratory (DUGL). Methods: The growth curve, morphological, and quantitative proteomic experiments were performed on FD-LSC-1 cells cultured in the DUGL and above-ground laboratory (AGL). Results: The proliferation of FD-LSC-1 cells from the DUGL group was delayed compared to that of cells from the AGL group. Transmission electron microscopy scans of the cells from the DUGL group indicated the presence of hypertrophic endoplasmic reticulum (ER) and a higher number of ER. At a cutoff of absolute fold change ≥ 1.2 and p < 0.05, 807 differentially abundant proteins (DAPs; 536 upregulated proteins and 271 downregulated proteins in the cells cultured in the DUGL) were detected. KEGG pathway analysis of these DAPs revealed that seven pathways were enriched. These included ribosome (p < 0.0001), spliceosome (p = 0.0001), oxidative phosphorylation (p = 0.0001), protein export (p = 0.0001), thermogenesis (p = 0.0003), protein processing in the endoplasmic reticulum (p = 0.0108), and non-alcoholic fatty liver disease (p = 0.0421). Conclusion: The BBR environment inhibited the proliferation of FD-LSC-1 cells. Additionally, it induced changes in protein expression associated with the ribosome, gene spliceosome, RNA transport, and energy metabolism among others. The changes in protein expression might form the molecular basis for proliferation inhibition and enhanced survivability of cells adapting to BBR exposure in a deep underground environment. RPL26, RPS27, ZMAT2, PRPF40A, SNRPD2, SLU7, SRSF5, SRSF3, SNRPF, WFS1, STT3B, CANX, ERP29, HSPA5, COX6B1, UQCRH, and ATP6V1G1 were the core proteins associated with the BBR stress response in cells.


Asunto(s)
Neoplasias de Cabeza y Cuello , Proteómica , Radiación de Fondo , Proliferación Celular , Chaperón BiP del Retículo Endoplásmico , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello
14.
Sci Rep ; 10(1): 14921, 2020 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-32913333

RESUMEN

As resources in the shallow depths of the earth exhausted, people will spend extended periods of time in the deep underground space. However, little is known about the deep underground environment affecting the health of organisms. Hence, we established both deep underground laboratory (DUGL) and above ground laboratory (AGL) to investigate the effect of environmental factors on organisms. Six environmental parameters were monitored in the DUGL and AGL. Growth curves were recorded and tandem mass tag (TMT) proteomics analysis were performed to explore the proliferative ability and differentially abundant proteins (DAPs) in V79 cells (a cell line widely used in biological study in DUGLs) cultured in the DUGL and AGL. Parallel Reaction Monitoring was conducted to verify the TMT results. γ ray dose rate showed the most detectable difference between the two laboratories, whereby γ ray dose rate was significantly lower in the DUGL compared to the AGL. V79 cell proliferation was slower in the DUGL. Quantitative proteomics detected 980 DAPs (absolute fold change ≥ 1.2, p < 0.05) between V79 cells cultured in the DUGL and AGL. Of these, 576 proteins were up-regulated and 404 proteins were down-regulated in V79 cells cultured in the DUGL. KEGG pathway analysis revealed that seven pathways (e.g. ribosome, RNA transport and oxidative phosphorylation) were significantly enriched. These data suggest that proliferation of V79 cells was inhibited in the DUGL, likely because cells were exposed to reduced background radiation. The apparent changes in the proteome profile may have induced cellular changes that delayed proliferation but enhanced survival, rendering V79 cells adaptable to the changing environment.


Asunto(s)
Radiación de Fondo , Proliferación Celular , Ambiente , Regulación de la Expresión Génica/efectos de la radiación , Laboratorios/estadística & datos numéricos , Proteínas/metabolismo , Proteoma/análisis , Animales , Células CHO , Biología Computacional , Cricetinae , Cricetulus , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Laboratorios/clasificación , Proteínas/genética , Proteoma/efectos de la radiación
15.
ACS Appl Mater Interfaces ; 12(40): 44858-44865, 2020 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-32924428

RESUMEN

To achieve high-performance thermoelectric (TE) devices, constructing a good interfacial connection between TE materials and electrodes is as important as having high figure-of-merit TE materials. Although CoSb3-based TE devices have received great attention for power generation recently, the limited long-term service stability is the main obstruct for their applications. In this work, we have prepared two kinds of Ti-based alloys (Ti83.7Al10.7Si5.6 and Ti74Ni26) as the diffusion barrier layer of CoSb3-based TE joints by the spark plasma sintering method and have systematically investigated their interfacial behaviors during the aging process. The performances of contact resistivity and mechanical strength for Ti74Ni26/Yb0.4Co3.8Fe0.2Sb12 TE joints are good before aging treatment but gradually deteriorate during the aging process, which should be ascribed to the phase-transition-induced negative thermal expansion in Ti-Ni alloys. On the other hand, Ti83.7Al10.7Si5.6/Yb0.4Co3.8Fe0.2Sb12 TE joints show both low contact resistivity (<10 µΩ·cm2) and high mechanical strength (>20 MPa) before and after 16-day aging at 500 °C, which is originated from the matching of the coefficient of thermal expansion (CTE) and the formation of network structures in Ti-Al-Si alloys. We have also prepared an eight-couple TE module of p-Ge0.9Sb0.1TeB0.01/n-Yb0.4Co3.8Fe0.2Sb12 and have measured its corresponding device performance. Our work has demonstrated that the matched CTE and network structures in the Ti-Al-Si alloy are key to obtain high-performance CoSb3-based TE joints for long-term service.

16.
ACS Appl Mater Interfaces ; 12(28): 31619-31627, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32539321

RESUMEN

For decades, the V2VI3 compounds, specifically p-type Bi2-xSbxTe3 and n-type Bi2Te3-xSex, have remained the cornerstone of commercial thermoelectric solid-state cooling and power generation near room temperature. However, a long-standing problem in V2VI3 thermoelectrics is that n-type Bi2Te3-xSex is inferior in performance to p-type Bi2-xSbxTe3 near room temperature, restricting the device efficiency. In this work, we developed high-performance n-type Bi2-xSbxTe3, a composition long thought to only make good p-type thermoelectrics, to replace the mainstream n-type Bi2Te3-xSex. The success arises from the synergy of the following mechanisms: (i) the donorlike effect, which produces excessive conduction electrons in Bi2Te3, is compensated by the antisite defects regulated by Sb alloying; (ii) the conduction band degeneracy increases from 2 for Bi2Te3 and Bi2Te3-xSex to 6 for Bi2-xSbxTe3, favoring high Seebeck coefficients; and (iii) the larger mass fluctuation yet smaller electronegativity difference and smaller atomic radius difference between Bi and Sb effectively suppresses the lattice thermal conductivity and retains decent carrier mobility. A state-of-the-art zT of 1.0 near room temperature was attained in hot deformed Bi1.5Sb0.5Te3, which is higher than those for most known n-type thermoelectric materials, including commercial Bi2Te3-xSex ingots and the popular Mg3Sb2. Technically, building both the n-leg and p-leg of a thermoelectric module using similar chemical compositions has key advantages in the mechanical strength and the durability of devices. These results attested to the promise of n-type Bi2-xSbxTe3 as a replacement of the mainstream n-type Bi2Te3-xSex near room temperature.

17.
Addict Behav ; 108: 106363, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32434104

RESUMEN

The present study aims to provide electrophysiological evidence for deficient inhibitory control in problematic mobile phone use and to investigate whether reduced inhibition is more pronounced during exposure to a mobile phone related background cue. A screen scale of smartphone addiction was completed by 227 college students, and finally an experimental group and a control group consisting of 20 problematic mobile phone users and 19 controls were included in the study. Event-related potentials were recorded during a backgrounded Go/NoGo task performed by those two groups, in which either a frequent Go signal (letter "M") or a rare NoGo signal (letter "W") was superimposed on three different background cues: neutral, mobile phone application-related and mobile phone using-related pictures. Results showed that problematic mobile phone users performed more commission errors than controls following mobile phone application background. Furthermore, problematic mobile phone users displayed a weaker NoGo P3 amplitude than controls on the mobile phone application background. The result might suggest that there is no general impairment of inhibitory control in problematic mobile phone use. The deficient inhibitory control on behavioral and psychophysiological level appeared merely in the mobile phone-related background. Such deficient stimuli-specific inhibitory control appears at the late stage of inhibitory control. Prevention programs should be designed to curtail exposure to the mobile phone-related stimulus and enhance cognitive control of potential problematic mobile phone users.


Asunto(s)
Uso del Teléfono Celular , Teléfono Celular , Señales (Psicología) , Potenciales Evocados , Humanos , Inhibición Psicológica
18.
ACS Appl Mater Interfaces ; 12(16): 18562-18569, 2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32227879

RESUMEN

To build high-performance thermoelectric (TE) devices for power generation, a suitable diffusion-barrier layer between the electrodes and the TE materials in a TE device is generally required for achieving good interfacial connection with high reliability, high mechanical strength but low electrical and thermal contact resistivities. GeTe-based materials have attracted great attention recently due to their high TE performance in the mid-temperature range, but studies on their TE devices are still limited. Here, we selected the Al66Si34 alloy as a diffusion barrier for GeTe-based TE legs based on the matching test of the coefficient of thermal expansion. The good connection between Al66Si34 and Ge0.9Sb0.1TeB0.01 is realized by the interfacial reaction, where the randomly distributed Al2Te3 and Ge precipitates are formed at the interface of the joint. The as-prepared interfacial electrical contact resistivity can be as low as 20.7 µΩ·cm2 and only slightly increases to 26.1 µΩ·cm2 after 16 days of aging at 500 °C. Moreover, the shear strength of the joints can be as high as 26.6 MPa and unexpectedly increases to 41.7 MPa after 16 days of aging. The thickness of the reaction layer tends to be stabilized after 8 days of aging and nearly does not change after further aging to 16 days, which may be ascribed to the drag effect from Si and the secondary Ge phases. These results demonstrate the great potential of the Al-Si alloy as a diffusion barrier for GeTe-based TE devices with high performance.

19.
Medicine (Baltimore) ; 99(9): e19294, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32118742

RESUMEN

The aim of the present study was to reveal the physical symptom changes and their correlations with mental health status in deep underground miners.A total of 286 deep underground miners completed a cross-sectional questionnaire study at China Pingmei Shenma mine complex. The questionnaire included sociodemographics, self-reported physical symptoms, underground adverse environmental factors, and the Symptom Checklist-90-Revised (SCL-90-R). Five environmental parameters of 1 deep mine were also measured.Data from 266 valid questionnaires were analyzed. The 3 most frequent complaints about underground adverse conditions were moisture [62.03% (165/266)], dim light [45.86% (122/266)], and high temperature [42.11% (112/266)]. Fatigue [40.22% (107/266)], hearing loss [34.96% (93/266)], and tinnitus [31.58% (84/266)] were reported to be the three most common physical symptoms. Insomnia was reported in 204 participants (76.69%) mainly due to the difficulty of falling asleep [42.35% (84/204)] and dreams [39.70% (81/204)]. Mean scores of SCL-90-R subscales including somatization, anxiety, phobic anxiety, psychoticism, and paranoid ideation were elevated compared to Chinese norms, while there was diminished interpersonal sensitivity. Univariate analyses indicated that the 3 most common physical symptoms were associated with poorer SCL-90-R scores. With increasing depth below ground, air pressure, relative humidity, CO2 concentration and temperature rose, while total gamma radiation dose-rate decreased.The physical and mental health status of deep underground miners was poorer than the general Chinese male population. Some adverse environmental factors were identified that may have influenced health status. Measures are suggested to improve the deep underground working environment.


Asunto(s)
Salud Mental/normas , Síndrome , Lugar de Trabajo/psicología , Adulto , China , Correlación de Datos , Estudios Transversales , Humanos , Masculino , Salud Mental/estadística & datos numéricos , Persona de Mediana Edad , Mineros , Psicometría/instrumentación , Psicometría/métodos , Encuestas y Cuestionarios , Factores de Tiempo , Lugar de Trabajo/normas
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