To ensure optimum working conditions for lithium-ion batteries, a numerical study is carried out for three-dimensional temperature distribution of a battery liquid cooling system in this work. The ...effect of channel size and inlet boundary conditions are evaluated on the temperature field of the battery modules. Based on the thermal behavior of discharging battery obtained experimental measurements, two temperature control strategies are proposed and studied. The results show that the channel width of the cooling plates has a great influence on the maximum temperature in the battery module. It is also revealed that increasing inlet water flow rate can significantly improve the heat transfer capacity of the battery thermal management system, while the relationship between them is not proportional. Lowering the inlet temperature can reduce the maximum temperature predicted in the battery module significantly. However, this will also lead to additional energy consumed by the cooling system. It is also found that the Scheme 5 among various temperature control strategies can ensure the battery pack working in the best temperature range in different depths of discharge. Compared with the traditional one with a given flow rate, the parasitic energy consumption in Scheme 5 can be reduced by around 80%.
Human activities and climate change pose major challenges for the sustainable development of terrestrial biological forests. The modern vegetation in the Baishanzu area is typical mixed subtropical ...evergreen broad-leaved, coniferous, and deciduous broad-leaved forest, with a vegetation combination sensitive to climate change. Higher resolution pollen records from the Shangyang Lake Wetland, located in the subtropical monsoon climate of the Baishanzu area in Zhejiang, China, were combined with environmental proxy data, such as data on loss on ignition and charcoal, to reconstruct the vegetation and climate changes since the Holocene. The results show that the climate was cool and dry during the early Holocene (11660–6580 cal. aBP), when the zonal vegetation changed from evergreen deciduous broad-leaved mixed forests dominated by evergreen Quercus (Quercus(E)), Castanopsis, deciduous Quercus (Quercus(D)), and Castanea to coniferous and broad-leaved mixed forests with rich Cryptomeria. Abies pollen spread to lower altitudes during the period 9620–8020 cal. aBP with Abies beshanzuensis covering large areas of land. The increased in the East Asian summer monsoon from 6580 to 2040 cal. aBP led to the Holocene Climate Optimum, when the climate was particularly warm and humid. The zonal vegetation was middle subtropical evergreen broad-leaved forest dominated by Quercus(E), Castanopsis, and Cyclobalanopsis with particularly high forest coverage and few fire events. For the last 2000 years, coniferous and broad-leaved mixed forests, mainly Pinus taiwanensis, have dominated the vegetation in the area. Sharp increase in such flora was observed after the year 980. Decreased temperature, cold climate, and increased anthropogenic disturbances have resulted in a substantial reduction in the arboreal pollen content, including Quercus, Castanopsis, Castanea, and Ilex, and an increase in Pinus and Poaceae. The results of this study will play a positive role in fully understanding the historical background and internal mechanisms of subtropical forest changes.
•Human activities and climate change pose major challenges for biological forests.•Baishanzu area experienced a cool and dry climate during the early Holocene.•Data suggested a Holocene climate optimum during the period of 6580–2040 cal. aBP.•Abies pollen in Shangyang Lake may originate from higher-altitude mountains.
Abstract
Coherent quantum transduction between microwave and optical signals is of great importance for long-distance quantum communication. Here we propose a novel scheme for the implementation of ...nonreciprocal single-photon state conversion between microwave and optical modes based on a hybrid magnonic system. A yttrium–iron–garnet (YIG) sphere with both the optomechanical and the optomagnetic properties is exploited to couple with a three-dimensional superconducting microwave resonator. The magnetostatic mode of the YIG sphere is treated as an intermediate to interact with the microwave and optical modes simultaneously. By manipulating the amplitudes and phase differences between the couplings via external driving fields, we show that the nonreciprocal microwave-light single-photon state conversion can be realized via the quantum interference effect.
Polypyrrole (PPy) has high electrical conductivity, good environmental stability, and reversible electrochemical redox characteristics, which makes PPy responsive to changes in environmental humidity ...values. In this work, a humidity sensor with a good response to humidity was prepared using in situ polymerization of PPy in filter paper doping with acetic acid. A possible sensing mechanism of conductive polymers is proposed and the conjecture is verified by experiments. The results demonstrated that the PPy/filter paper-based humidity sensor provides an electron migration channel with the capability of detecting the relative humidity. External humidity stimulation can regulate the electrochemical reaction of PPy. The reduction reaction occurs near the water side to generate the nucleophilic product OH–. The PPy system loses electrons to form carrier directional channels, resulting in changes in the output voltage measured between the two electrodes. The PPy/filter paper-based humidity sensor exhibits the moisture dependent voltage response over a wide range from a relative humidity of 11–98%, and a response/recovery time of 43/51 s as it was placed between relative humidity of 33% and 98%. In addition, unlike the traditional sensing mechanism, the voltage sensing mechanism raised here shows self-powered ability with no need for an additional power unit. This provides a new idea for self-powered sensor devices, and this sensor shows good performance in non-contact sensing applications such as breath detection.
The machine vision system was employed to inspect the surface defects of bridge cables of cable-stayed bridges. After the acquisition and preprocessing of the defect images, it is necessary to ...classify and identify the defects of the cables to meet the requirements of non-destructive testing and evaluation. In this paper, feature extraction for defect images was performed using mathematical statistical methods. After that, 10 feature parameters including shape features, grayscale features and texture features of the defect images were obtained and selected for a classification model of support vector machine (SVM). To improve the SVM classification performance, the particle swarm optimization algorithm (PSO) was adopted to obtain the punish factor c and the kernel parameter g of the SVM model, namely the PSO-SVM algorithm. Finally, our PSO-SVM classification model was employed to implement the classification of real surface defect images of the bridge cables. Longitudinal crack, transverse crack, surface corrosion, and pothole defect can be automatically identified and the classification accuracy reached 96.25%. The experimental results showed that the PSO-SVM model can improve the classification performance of the surface defects. Based on the effective classification, we can find the distribution characteristics of the surface defects of the cable. It is very important to analyze the relationship between the type of surface defects and the material of the protective layer, so as to adopt appropriate materials and reasonable maintenance measures. Thus, it has a great significance in the structural health monitoring of bridge cables.
In this study, a three-dimensional transient simulation model of a liquid cooling thermal management system with flow distributors and spiral channel cooling plates for pouch lithium-ion batteries ...has been developed. The cooling plates play the role of uniforming temperature distribution and reducing the maximum temperature within each battery, while the flow distributors have the function of reducing the temperature difference between batteries in the battery module. The accuracy of the thermophysical properties and heat generation rate of the battery was verified experimentally. The optimal structure and cooling strategy of the system was determined by single factor analysis as well as orthogonal test and matrix analysis methods. The optimal solution resulted in a maximum battery module temperature of 34.65 °C, a maximum temperature difference of 3.95 °C, and a channel pressure drop of 8.82 Pa. Using the world-harmonized light-duty vehicles test cycle (WLTC) conditions for a battery pack in an electric car, the performance of the optimal battery thermal management system (BTMS) design was tested, and the results indicate that the maximum temperature can be controlled below 25.51 °C and the maximum temperature difference below 0.21 °C, which well meet the requirements of BTMS designs.
Xylanase plays a key role in degrading plant cell wall during pathogenic fungi infection. Here, we identified a xylanase gene,
from the transcriptome of
and examined its function.
has highly elevated ...transcript levels during the infection process of
, with 15.02-fold increase. Deletion mutants of the gene were generated to investigate the necessity of
in the development and pathogenicity of
. The
deletion mutant considerably reduced the virulence of
in apple leaves and in twigs, accompanied by 41.22% decrease in xylanase activity. In addition, we found that VmXyl2 induces plant cell necrosis regardless of its xylanase activity, whereas promoting the infection of
in apple tissues. The cell death-inducing activity of VmXyl2 dependent on BRI1-associated kinase-1 (BAK1) but not Suppressor of BIR1-1 (SOBIR1). Furthermore, VmXyl2 interacts with Mp2
, a receptor-like kinase with leucine-rich repeat. The results offer valuable insights into the roles of VmXyl2 in the pathogenicity of
during its infection of apple trees.
Although the importance of coral holobionts is widely accepted, the relationship between the flexibility of the microbial structure and the coral host is very complicated. Particularly, the community ...dynamics of holobionts and the stability of host-microbe interactions under different thermal stresses remain largely unknown. In the present study, we holistically explored the physiology and growth of
in response to increased temperatures (from 26 to 33°C). We observed that bleaching corals with loss of algal symbionts reduced lipids and proteins to maintain their survival, leading to decreased tissue biomass and retarded growth. The diversity of Symbiodiniaceae and symbiont shuffling in the community structure was mainly caused by alterations in the relative abundance of the thermally sensitive but dominant clade C symbionts and low abundance of "background types." Bacterial diversity showed a decreasing trend with increasing temperature, whereas no significant shifts were observed in the bacterial community structure. This finding might be attributed to the local adjustment of specific microbial community members that did not affect the overall metabolic state of the coral holobiont, and there was no increase in the proportion of sequences identified as typically pathogenic or opportunistic taxa. The Sloan neutral community model showed that neutral processes could explain 42.37-58.43% of bacterial community variation. The Stegen null model analysis indicates that the stochastic processes explain a significantly higher proportion of community assembly than deterministic processes when the temperature was elevated. The weak effect of temperature on the bacterial community structure and assembly might be related to an increase in stochastic dominance. The interaction of bacterial communities exhibits a fluctuating and simplistic trend with increasing temperature. Moreover, temperature increases were sufficient to establish the high stability of bacterial networks, and a non-linear response was found between the complexity and stability of the networks. Our findings collectively provide new insights into successive changes in the scleractinian coral host and holobionts in response to elevated seawater temperatures, especially the contribution of the community assembly process and species coexistence patterns to the maintenance of the coral-associated bacterial community.
Rheumatoid arthritis (RA) is a systemic autoimmune disease, in addition, gut microbiota plays an important role in the etiology of RA. However, our understanding of alterations to the gut fungal ...microbiota in Chinese population with RA is still limited.
Serum samples were obtained from 62 patients with RA, and 39 age- and gender-matched healthy controls (HCs). Fecal samples were obtained from 42 RA patients and 39 HCs. Fecal fungal microbiota targeting internal transcribed spacer region 2 (ITS2) rRNA genes was investigated using MiSeq sequencing, as well as their associations with some diagnostic biomarkers for RA.
Our results showed that the fungal diversity did not alter in RA patients but taxonomic composition of the fecal fungal microbiota did. The gut mycobiota of RA patients was characterized by decreased abundance of
,
, and
. The linear discriminant analysis (LDA) effect size analysis (LEfSe) analysis identified several RA-enriched fungal genera, which were positively correlated with most RA biomarkers. Furthermore, since RA is an age- and gende-related disease, we classified RA patients into subgroups with age and gender and analyzed the sequencing results. Our data demonstrated that
and
were the most discriminatory against RA patients over 60 years old, while
was the most discriminatory against female RA patients.
The case-control study presented here confirmed the alterations of gut fungal microbiota in Chinese patients with RA, and we speculated that the fungal dysbiosis may contribute to RA development.
Fluorescence, and more in general, photoluminescence (PL), presents important advantages for imaging with respect to other diagnostic techniques. In particular, detection methodologies exploiting ...fluorescence imaging are fast and versatile; make use of low-cost and simple instrumentations; and are taking advantage of newly developed powerful, low-cost, light-based electronic devices, such as light sources and cameras, used in huge market applications, such as civil illumination, computers, and cellular phones. Besides the aforementioned simplicity, fluorescence imaging offers a spatial and temporal resolution that can hardly be achieved with alternative methods. However, the two main limitations of fluorescence imaging for bio-application are still (i) the biological tissue transparency and autofluorescence and (ii) the biocompatibility of the contrast agents. Luminescent gold nanoclusters (AuNCs), if properly designed, combine high biocompatibility with PL in the near-infrared region (NIR), where the biological tissues exhibit higher transparency and negligible autofluorescence. However, the stabilization of these AuNCs requires the use of specific ligands that also affect their PL properties. The nature of the ligand plays a fundamental role in the development and sequential application of PL AuNCs as probes for bioimaging. Considering the importance of this, in this review, the most relevant and recent papers on AuNCs-based bioimaging are presented and discussed highlighting the different functionalities achieved by increasing the complexity of the ligand structure.
PDF
