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1.
Sci Rep ; 14(1): 6988, 2024 03 24.
Article in English | MEDLINE | ID: mdl-38523175

ABSTRACT

Habitat fragmentation has led to a reduction in the geographic distribution of species, making small populations vulnerable to extinction due to environmental, demographic, and genetic factors. The wild plant Chieniodendron hainanense, a species with extremely small populations, is currently facing endangerment and thus requires urgent conservation efforts. Understanding its genetic diversity is essential for uncovering the underlying mechanisms of its vulnerability and for developing effective conservation strategies. In our study, we analyzed 35 specimens from six different populations of C. hainanense using genotyping-by-sequencing (GBS) and single nucleotide polymorphism (SNP) methodologies. Our findings indicate that C. hainanense has limited genetic diversity. The observed heterozygosity across the populations ranged from 10.79 to 14.55%, with an average of 13.15%. We categorized the six populations of C. hainanense into two distinct groups: (1) Diaoluoshan and Baishaling, and (2) Wuzhishan, Huishan, Bawangling, and Jianfengling. The genetic differentiation among these populations was found to be relatively weak. The observed loss of diversity is likely a result of the effects of natural selection.


Subject(s)
Endangered Species , Genetics, Population , Animals , Genetic Drift , Ecosystem , Polymorphism, Single Nucleotide , Genetic Variation
2.
Chem Commun (Camb) ; 60(30): 4104-4107, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38516856

ABSTRACT

By constructing a Ag2O/Bi4O5I2 p-n heterojunction and applying a heat-localization microreactor, efficient photocatalysis enhanced by both photoinduced carrier separation and the photothermal effect was realized. This work focuses on the utilization of near-infrared light to broaden the absorption spectrum and accelerate the transportation of carriers. Through the production and localization of heat, it provides a novel thought for full-spectrum photocatalysis.

3.
J Phys Chem Lett ; 15(5): 1412-1419, 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38290430

ABSTRACT

Owing to its unique layered structure, BiOCl demonstrates high photocatalytic activity. However, its wide bandgap hinders the absorption of visible light. Doping modification is an effective method to expand the light absorption edge of photocatalysts by creating a doping energy level within the bandgap. Herein, Co as a variable valence element was used to dope the BiOCl nanosheets through a simple hydrothermal approach. As a result, the absorption edge of Co-BiOCl extends to the visible light region, and the photocatalytic performance was enhanced by 3.02 times. To overcome the shortcoming of photons being consumed easily in the bulk reactor, a planar microreactor was introduced to reduce the attenuation of light and accelerate the mass transfer. By comparison to the bulk reactor, a maximum of 15.3-fold additional activity promotion emerged. This work combines doping modification and reactor improvement to realize highly efficient photocatalysis in practical application.

4.
Biochem Pharmacol ; 220: 115938, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38086488

ABSTRACT

The stimulator of interferon genes (STING) is a crucial signaling hub in the immune system's antiviral and antimicrobial defense by detecting exogenous and endogenous DNA. The multifaceted functions of STING have been uncovered gradually during past decades, including homeostasis maintenance and overfull immunity or inflammation induction. However, the subcellular regulation of STING and mitochondria is poorly understood. The main functions of STING are outlined in this review. Moreover, we discuss how mitochondria and STING interact through multiple mechanisms, including the release of mitochondrial DNA (mtDNA), modulation of mitochondria-associated membrane (MAM) and mitochondrial dynamics, alterations in mitochondrial metabolism, regulation of reactive oxygen species (ROS) production, and mitochondria-related cell death. Finally, we discuss how STING is crucial to disease development, providing a novel perspective on its role in cellular physiology and pathology.


Subject(s)
DNA, Mitochondrial , Mitochondria , Humans , DNA, Mitochondrial/genetics , DNA, Mitochondrial/metabolism , Homeostasis , Immunity, Innate , Inflammation/metabolism , Mitochondria/metabolism , Signal Transduction
5.
Sci Rep ; 13(1): 22438, 2023 12 17.
Article in English | MEDLINE | ID: mdl-38105276

ABSTRACT

This study explored the influence of climatic oscillations on the striped, blue, and silver marlin catch rates in the Indian Ocean by using logbook data from Taiwanese large-scale fishing vessels and climate records from 1994 to 2016. Only the Madden-Julian oscillation (MJO) and the subtropical Indian Ocean dipole (SIOD) had immediate effects on the striped and silver marlin catch rates. The positive and negative phases of the IOD at the lags of 7 and 3 years corresponded to increased and decreased catch rates, respectively, for both the striped and blue marlin, contrasting to the reverse pattern for the silver marlin. Similarly, all three marlin species experienced decreased and increased catch rates respectively during the positive and negative phases of the Pacific decadal oscillation. The striped and blue marlin catch rates decreased and increased during the positive and negative phases, respectively, of the SIOD and MJO with various lags. Our results suggest that the impacts of climatic oscillations on fish species are crucial for policymakers and coastal communities for managing marine resources, forecasting changes in marine ecosystems, and developing strategies to adapt to and mitigate the effects of climate variability.


Subject(s)
Ecosystem , Silver , Animals , Indian Ocean
6.
J Colloid Interface Sci ; 652(Pt A): 963-970, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37634369

ABSTRACT

Hindering the recombination of photoinduced electron-hole pairs is of significance for enhancing photocatalytic performance. Applying a voltage to separate carriers offers an option to realize it. Thermoelectric materials own the ability to continuously sustain a voltage when a temperature difference exists between its two sides. However, maintaining the thermoelectric effect without wasting additional energy remains a challenge. Herein, a C3N4/Polyaniline/Poly(vinylidene fluoride) cilia array was fabricated to reach efficient photocatalysis through thermoelectric effect and photothermal effect. The cilia array structure offers more than 40% of light absorbance compared to the film. Hence, the infrared light in sunlight, which was usually omitted in photocatalysis, was transformed into heat. Through the unique design which draws upon the huge difference in thermal conductivity of air and water, a temperature gap was formed between the top and bottom sides of the cilia array by half-submerging it in water. Therefore, the photocatalytic efficiency was improved by 84.4%. This work achieves an energy-saving method to enhance photocatalytic performance by activating thermoelectric effect through infrared light, shedding light on the application of multi-modes enhanced photocatalysis.

7.
Phys Med Biol ; 68(10)2023 05 11.
Article in English | MEDLINE | ID: mdl-37171071

ABSTRACT

Purpose. Accurate image registration is an important step in online image-guided adaptive radiotherapy. The aim of this study was to investigate the effects of different factors on registration accuracy in a magnetic resonance (MR)-guided adaptive radiotherapy workflow.Materials and Methods. A thorax motion phantom was used to obtain computed tomography (CT) simulations in 8 different motion modes and to generate 8 reference plans. Daily pretreatment online MR images were obtained at 5 different positions in each reference plan. Online MR and CT simulations were separately registered using bone structures and the gross tumor volume (GTV) as ROIs, and the image shift distance was recorded by the online treatment planning system. The difference between the shift distance and the real isocentric distance was the registration error. The registration error was analyzed, and the effects of the setup position, motion mode and ROI selection on the registration error were investigated by multivariate analysis of variance.Result. The minimum values of registration error (ΔX, ΔY, ΔZ) were -1.90 mm, -2.70 mm and -2.40 mm, respectively, and the maximum values were 1.70 mm, 4.30 mm and -0.90 mm. ΔY showed the maximum mean standard deviation of 1.25 mm, and ΔZshowed the minimum mean standard deviation of 0.27 mm. The standard deviation of the registration error is largest in the inferior/superior direction. The motion mode of the phantom and ROI selection were significantly correlated with ΔX, ΔY, and ΔZ(p< 0.05).Conclusion. The registration result with the spine as the selected ROI was better than that with the GTV as the ROI. In 1.5 T MR-linac clinical treatment, more attention should be given to patient movement repeatability and to controlling the intrafractional motion as much as possible. It is not recommended to make the GTV-PTV margin expansion less than 2 mm for MR-linac.


Subject(s)
Radiotherapy Planning, Computer-Assisted , Radiotherapy, Image-Guided , Humans , Radiotherapy Planning, Computer-Assisted/methods , Magnetic Resonance Imaging/methods , Radiotherapy, Image-Guided/methods , Particle Accelerators , Tomography, X-Ray Computed , Radiotherapy Dosage
8.
J Contemp Brachytherapy ; 15(2): 134-140, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37215613

ABSTRACT

Purpose: The purpose of this study was to investigate the precision of deep learning (DL)-based auto-reconstruction in localizing interstitial needles in post-operative cervical cancer brachytherapy (BT) using three-dimensional (3D) computed tomography (CT) images. Material and methods: A convolutional neural network (CNN) was developed and presented for automatic reconstruction of interstitial needles. Data of 70 post-operative cervical cancer patients who received CT-based BT were used to train and test this DL model. All patients were treated with three metallic needles. Dice similarity coefficient (DSC), 95% Hausdorff distance (95% HD), and Jaccard coefficient (JC) were applied to evaluate the geometric accuracy of auto-reconstruction for each needle. Dose-volume indexes (DVI) between manual and automatic methods were used to analyze the dosimetric difference. Correlation between geometric metrics and dosimetric difference was evaluated using Spearman correlation analysis. Results: The mean DSC values of DL-based model were 0.88, 0.89, and 0.90 for three metallic needles. Wilcoxon signed-rank test indicated no significant dosimetric differences in all BT planning structures between manual and automatic reconstruction methods (p > 0.05). Spearman correlation analysis demonstrated weak link between geometric metrics and dosimetry differences. Conclusions: DL-based reconstruction method can be used to precisely localize the interstitial needles in 3D-CT images. The proposed automatic approach could improve the consistency of treatment planning for post-operative cervical cancer brachytherapy.

9.
Front Plant Sci ; 14: 1121759, 2023.
Article in English | MEDLINE | ID: mdl-36875604

ABSTRACT

[This corrects the article DOI: 10.3389/fpls.2022.1075102.].

10.
PeerJ ; 11: e14990, 2023.
Article in English | MEDLINE | ID: mdl-36919168

ABSTRACT

The location, effort, number of captures, and time of fishing were all used in this study to assess the geographic distribution of Parastromateus niger in the Taiwan Strait. Other species distribution models performed worse than generalized linear models (GLMs) based on six oceanographic parameters. The sea surface temperature (SST) was between 26.5 °C and 29.5 °C, the sea surface chlorophyll (SSC) level was between 0.3-0.44 mg/m3, the sea surface salinity (SSS) was between 33.4 °C and 34.4 °C, the mixed layer depth was between 10 °C and 14 °C, the sea surface height was between 0.57 °C and 0.77 °C, and the eddy kinetic energy (EKE) was between 0.603 °C. According to the statistical findings, SST is merely a small effect compared to SSS, SSC level, and EKE in terms of impacting species distribution. By combining four effective single-algorithm models with no obvious bias, an ensemble habitat model was created. The ranges of 117°E-119°E and 22°N-24°N have the highest annual distributions of S.CPUE and nominal CPUE.


Subject(s)
Chlorophyll , Ecosystem , Animals , Niger , Taiwan , Fishes
11.
Phys Med Biol ; 68(5)2023 02 23.
Article in English | MEDLINE | ID: mdl-36753762

ABSTRACT

Objective. The purpose of this study was to evaluate the accuracy of brachytherapy (BT) planning structures derived from Deep learning (DL) based auto-segmentation compared with standard manual delineation for postoperative cervical cancer.Approach. We introduced a convolutional neural networks (CNN) which was developed and presented for auto-segmentation in cervical cancer radiotherapy. The dataset of 60 patients received BT of postoperative cervical cancer was used to train and test this model for delineation of high-risk clinical target volume (HRCTV) and organs at risk (OARs). Dice similarity coefficient (DSC), 95% Hausdorff distance (95%HD), Jaccard coefficient (JC) and dose-volume index (DVI) were used to evaluate the accuracy. The correlation between geometric metrics and dosimetric difference was performed by Spearman's correlation analysis. The radiation oncologists scored the auto-segmented contours by rating the lever of satisfaction (no edits, minor edits, major edits).Main results. The mean DSC values of DL based model were 0.87, 0.94, 0.86, 0.79 and 0.92 for HRCTV, bladder, rectum, sigmoid and small intestine, respectively. The Bland-Altman test obtained dose agreement for HRCTV_D90%, HRCTV_Dmean, bladder_D2cc, sigmoid_D2ccand small intestine_D2cc. Wilcoxon's signed-rank test indicated significant dosimetric differences in bladder_D0.1cc, rectum_D0.1ccand rectum_D2cc(P< 0.05). A strong correlation between HRCTV_D90%with its DSC (R= -0.842,P= 0.002) and JC (R= -0.818,P= 0.004) were found in Spearman's correlation analysis. From the physician review, 80% of HRCTVs and 72.5% of OARs in the test dataset were shown satisfaction (no edits).Significance. The proposed DL based model achieved a satisfied agreement between the auto-segmented and manually defined contours of HRCTV and OARs, although the clinical acceptance of small volume dose of OARs around the target was a concern. DL based auto-segmentation was an essential component in cervical cancer workflow which would generate the accurate contouring.


Subject(s)
Brachytherapy , Deep Learning , Uterine Cervical Neoplasms , Female , Humans , Brachytherapy/methods , Uterine Cervical Neoplasms/radiotherapy , Radiotherapy Dosage , Workflow , Radiotherapy Planning, Computer-Assisted/methods , Organs at Risk
12.
Small ; 19(18): e2207467, 2023 May.
Article in English | MEDLINE | ID: mdl-36634976

ABSTRACT

Utilization of low-energy photons for efficient photocatalysis remains a challenging pursuit. Herein, a strategy is reported to boost the photocatalytic performance, by promoting low-energy photons dual harvest through bimodal surface plasmon resonance (SPR)-enhanced synergistically upconversion and pyroelectricity. It is achieved by introducing triplet-triplet annihilation upconversion (TTA-UC) materials and plasmonic material (Au nanorods, AuNRs) into composite fibers composed of pyroelectric substrate (poly(vinylidene fluoride)) and photocatalyst Cd0.5 Zn0.5 S. Interestingly, the dual combination of TTA-UC and AuNRs SPR in the presence of polyvinylidene fluoride substrate with pyroelectric property promotes the photocatalytic hydrogen evolution performance by 2.88 folds with the highest average apparent quantum yield of 7.0% under the low-energy light (λ > 475 nm), which far outweighs the role of separate application of TTA-UC (34%) and AuNRs SPR (76%). The presence of pyroelectricity plays an important role in the built-in electric field as well as the accordingly photogenerated carrier behavior in the composite photocatalytic materials, and the pyroelectricity can be affected by AuNRs with different morphologies, which is proved by the Kelvin probe force microscopy and photocurrent data. This work provides a new avenue for fully utilizing low-energy photons in the solar spectrum for improving photocatalytic performance.

13.
Am J Hosp Palliat Care ; 40(11): 1271-1278, 2023 Nov.
Article in English | MEDLINE | ID: mdl-36503251

ABSTRACT

To demonstrate the trends and variety of research on palliative care during the COVID-19 pandemic. A systematic search of the Web of Science database. Since the outbroke of the COVID-19 pandemic, the adjustment of palliative care systems is warranted to maintain a high quality of care. The COVID-19 -related palliative care studies account for approximately 4% of all publications on palliative care. However, there is a dearth of research investigating the nature of these studies. A total of 293 studies were included. Of the included studies, those related to system improvement were the most common (181/293, 61.8%), followed by those related to patient care (79/293, 27.0%), bereavement support for patients or family members (19/293, 6.5%), and the mental health of frontline practitioners (14/293, 4.8%). From these studies, 82, 137, and 74 studies were published in 2020, 2021, and 2022 (until August 1), respectively. The research trends of palliative care demonstrate the flexibility and rapid response of the global palliative care system to the COVID-19 pandemic and show how the palliative care system is evolving. While most studies are interested in system improvement, patient care, and bereavement support, the mental health of frontline practitioners has received less attention. Our findings provide palliative care practitioners with current valuable information and highlight possible future trends.


Subject(s)
COVID-19 , Palliative Care , Humans , COVID-19/therapy , Hospice and Palliative Care Nursing , Palliative Care/trends , Pandemics , Terminal Care
14.
J Contemp Brachytherapy ; 15(6): 405-413, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38230396

ABSTRACT

Purpose: Although customized three-dimensional (3D) templates have shown advantages in brachytherapy, widespread application is still full of challenges. The present work proposed the use of a commercial 3D standardized template-guided intracavitary/interstitial brachytherapy (IC/ISBT) that could provide simple and reproducible needles' insertion. Material and methods: 43 patients received external beam radiotherapy (EBRT) with 45-50.4 Gy and subsequent IC/ISBT with 28 Gy in 4 fractions. In terms of IC/ISBT, 24 patients were treated with 3D standardized templates (ST group), and 19 patients were treated using free-hand implantation (FH group). Consistency of implantation for all needles and dosimetric differences for target and organs at risk (OARs) were then compared between two groups. Results: The mean variation of tip position between insertions for needles was 1.41 mm and 2.74 mm in ST group and FH group, respectively (p < 0.001). ST group was superior in terms of dosimetric conformity index (CI) and D90 for high-risk clinical target volume (HR-CTV), significantly improving to 23.21% (p < 0.001) and 3.58% (p = 0.031) compared with FH group. The D2cc of the bladder and sigmoid in the ST group were lower than those in the FH group (p < 0.05). Meanwhile, a strong correlation between the volume of HR-CTV and its CI in the ST group (R = 0.865, p < 0.001) was found with Spearman's correlation analysis. Conclusions: The implementation of 3D standardized template can potentially improve the precision and consistency in the needle insertion procedure that may replace some customized 3D templates, and achieve clinical satisfied dose distribution in IC/ISBT plans for patients with LACC.

15.
Front Plant Sci ; 13: 1075102, 2022.
Article in English | MEDLINE | ID: mdl-36570896

ABSTRACT

Hopea hainanensis (Dipterocarpaceae) is an endangered tree species restricted to Hainan Island, China, and a small part of Northern Vietnam. On Hainan Island, it is an important indicator species for tropical forests. The wood of Hopea hainanensis has a very high utilization value in nature since it is compact in structure, hard in texture, not easily deformed after drying, durable, and resistant to sunlight and water. As a result of its high quality, it has been felled and mined by humans without restraint, resulting in a reduction of its population size, severe habitat fragmentation, and a sharp decline in its population. Therefore, its conservation biology needs to be researched urgently. Researchers are currently focusing on the ecological factors and seed germination in the habitat of Hopea hainanensis to determine its endangered status. In the literature, there are no systematic analyses of the endangered mechanism of Hopea hainanensis in terms of genetic diversity. It focuses especially on the systematic genetic diversity of Hopea hainanensis in fragmented habitats. Using single nucleotide polymorphism (SNP) and genotyping-by-sequencing (GBS) technology, 42 samples from seven different cohabitation groups were genotyped. The results showed that the average heterozygosity of the six populations of Hopea hainanensis was 19.77%, which indicated that the genetic diversity of Hopea hainanensis was low. Genetic diversity research is essential for rare and endangered plant protection research. We can find a scientific basis for protecting endangered plants on slope bases by analyzing genetic differences and relationships among populations.

16.
Genes (Basel) ; 13(11)2022 11 04.
Article in English | MEDLINE | ID: mdl-36360265

ABSTRACT

Dendropanax oligodontus, which belongs to the family Araliaceae, is an endemic and endangered species of Hainan Island, China. It has potential economic and medicinal value owing to the presence of phenylpropanoids, flavonoids, triterpenoids, etc. The analysis of the structure and characteristics of the D. oligodontus chloroplast genome (cpDNA) is crucial for understanding the genetic and phylogenetic evolution of this species. In this study, the cpDNA of D. oligodontus was sequenced for the first time using next-generation sequencing methods, assembled, and annotated. We observed a circular quadripartite structure comprising a large single-copy region (86,440 bp), a small single-copy region (18,075 bp), and a pair of inverted repeat regions (25,944 bp). The total length of the cpDNA was 156,403 bp, and the GC% was 37.99%. We found that the D. oligodontus chloroplast genome comprised 131 genes, with 86 protein-coding genes, 8 rRNA genes, and 37 tRNAs. Furthermore, we identified 26,514 codons, 13 repetitive sequences, and 43 simple sequence repeat sites in the D. oligodontus cpDNA. The most common amino acid encoded was leucine, with a strong A/T preference at the third position of the codon. The prediction of RNA editing sites in the protein-coding genes indicated that RNA editing was observed in 19 genes with a total of 54 editing sites, all of which involved C-to-T transitions. Finally, the cpDNA of 11 species of the family Araliaceae were selected for comparative analysis. The sequences of the untranslated regions and coding regions among 11 species were highly conserved, and minor differences were observed in the length of the inverted repeat regions; therefore, the cpDNAs were relatively stable and consistent among these 11 species. The variable hotspots in the genome included clpP, ycf1, rnK-rps16, rps16-trnQ, atpH-atpI, trnE-trnT, psbM-trnD, ycf3-trnS, and rpl32-trnL, providing valuable molecular markers for species authentication and regions for inferring phylogenetic relationships among them, as well as for evolutionary studies. Evolutionary selection pressure analysis indicated that the atpF gene was strongly subjected to positive environmental selection. Phylogenetic analysis indicated that D. oligodontus and Dendropanax dentiger were the most closely related species within the genus, and D. oligodontus was closely related to the genera Kalopanax and Metapanax in the Araliaceae family. Overall, the cp genomes reported in this study will provide resources for studying the genetic diversity and conservation of the endangered plant D. oligodontus, as well as resolving phylogenetic relationships within the family.


Subject(s)
Genome, Chloroplast , Phylogeny , DNA, Chloroplast , Codon/genetics , Microsatellite Repeats
17.
J Clin Transl Hepatol ; 10(5): 879-890, 2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36304491

ABSTRACT

Background and Aims: Acute liver failure (ALF) is a potentially fatal clinical syndrome with no effective treatment. This study aimed to explore the role of Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) pathway in modulating the phenotype and immune function of endotoxin-tolerant dendritic cells (ETDCs). In addition, we explored the use of EDTCs in an experimental model of ALF and investigated the associated mechanisms. Methods: In the in vitro experiment, ETDCs were transfected with adenovirus to induce SOCS1+/+ETDCs and SOCS1-/-ETDCs. Thereafter, costimulatory molecules and mixed lymphocyte reaction were assessed. Experimental mice were randomly divided into normal control, ALF, ALF+mock-ETDCs, ALF+SOCS1+/+ETDCs, ALF+AG490, and ALF+AG490+SOCS1+/+ETDCs groups. We examined the therapeutic effect of adoptive cellular immunotherapy by tail-vein injection of target ETDCs 12 h before ALF modeling. AG490, a JAK2/STAT3 inhibitor, was used in the in vivo experiment to further explore the protective mechanism of SOCS1+/+ETDCs. Results: Compared with control ETDCs, SOCS1+/+ETDCs had lower expression of costimulatory molecules, weaker allostimulatory ability, lower levels of IL-6 and TNF-α expression and higher IL-10 secretion. SOCS1-/-ETDCs showed the opposite results. In the in vivo experiments, the ALF+SOCS1+/+ETDCs and ALF+AG490+SOCS1+/+ETDCs groups showed less pathological damage and suppressed activation of JAK2/STAT3 pathway. The changes were more pronounced in the ALF+AG490+SOCS1+/+ETDCs group. Infusion of SOCS1+/+ETDCs had a protective effect against ALF possibly via inhibition of JAK2 and STAT3 phosphorylation. Conclusions: The SOCS1 gene had an important role in induction of endotoxin tolerance. SOCS1+/+ETDCs alleviated lipopolysaccharide/D-galactosamine-induced ALF by downregulating the JAK2/STAT3 signaling pathway.

18.
Sci Rep ; 12(1): 18088, 2022 10 27.
Article in English | MEDLINE | ID: mdl-36302882

ABSTRACT

Of crucial importance for giant magnetostrictive transducers (GMTs) design is to quickly and accurately analysis the temperature distribution. With the advantages of low calculation cost and high accuracy, thermal network modelling has been developed for thermal analysis of GMT. However, the existing thermal models have their limits to describe these complicated thermal behaviors in the GMTs: most of researches focused on steady-state which is incapable of capturing temperature variances;  the temperature distribution of giant magnetostrictive (GMM) rods is generally assumed to be uniform whereas the temperature gradient on the GMM rod is remarkable due to its poor thermal conductivity;  the non-uniform distribution of GMM's losses is seldom introduced into thermal model. Therefore, a transient equivalent thermal network (TETN) model of GMT is established in this paper, considering the aforementioned three aspects. Firstly, based on the structure and working principle of a longitudinal vibration GMT, thermal analysis was carried out. Following this, according to the heat transfer process of GMT, the TETN model was established and the corresponding model parameters were calculated. Finally, the accuracy of the TETN model for the temporal and spatial analysis of the transducer temperature are verified by simulation and experiment.


Subject(s)
Hot Temperature , Transducers , Thermal Conductivity , Computer Simulation , Temperature
19.
Dalton Trans ; 51(40): 15205-15226, 2022 Oct 18.
Article in English | MEDLINE | ID: mdl-36125033

ABSTRACT

Hydrogen (H2) is a new type of renewable energy that can meet people's growing energy needs and is environmentally friendly. In order to improve the industrial application prospects and electrochemical performance of hydrogen evolution catalysts, extensive research on transition metal materials has been carried out. Among the many catalytic materials, cobalt is an element with potential for the hydrogen evolution reaction (HER) due to its abundant reserves, low cost, and small energy barrier for H adsorption. This review classifies the latest research on cobalt-based catalysts according to the types of compound, including cobalt-based sulfides, phosphides, carbides, borides, oxides, etc., and summarizes the latest research progress of cobalt-based compound catalysts in acidic and alkaline media. Strategies to tune the properties of cobalt-based compound catalysts for high catalytic activity for HER are focused on, including structural engineering, defect engineering, and doping, etc. The advantages and limitations of each modified approach are reviewed. Not only that, but also the catalytic activity and advantages of the catalyst are evaluated by using density functional theory (DFT) calculation-related descriptors, activity evaluation parameters, etc. Finally, limitations and challenges of cobalt-based materials for HER are presented, as well as prospects for future research. This paper aims to understand the chemical and physical factors that affect cobalt-based catalysts, and to find directions for future research on cobalt-based catalysts.

20.
Adv Sci (Weinh) ; 9(28): e2203057, 2022 10.
Article in English | MEDLINE | ID: mdl-35957518

ABSTRACT

Mass transfer is an essential factor determining photocatalytic performance, which can be modulated by fluid field via manipulating the kinetic characteristics of photocatalysts and photocatalytic intermediates. Past decades have witnessed the efforts and achievements made in manipulating mass transfer based on photocatalyst structure and composition design, and thus, a critical survey that scrutinizes the recent progress in this topic is urgently necessitated. This review examines the basic principles of how mass transfer behavior impacts photocatalytic activity accompanying with the discussion on theoretical simulation calculation including fluid flow speed and pattern. Meanwhile, newly emerged viable photocatalytic micro/nanomotors with self-thermophoresis, self-diffusiophoresis, and bubble-propulsion mechanisms as well as magnet-actuated photocatalytic artificial cilia for facilitating mass transfer will be covered. Furthermore, their applications in photocatalytic hydrogen evolution, carbon dioxide reduction, organic pollution degradation, bacteria disinfection and so forth are scrutinized. Finally, a brief summary and future outlook are presented, providing a viable guideline to those working in photocatalysis, mass transfer, and other related fields.


Subject(s)
Carbon Dioxide , Disinfection , Bacteria , Catalysis , Hydrogen
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