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Methoxypolyethylene glycol 1900 and α-bromoisobutanoyl bromide were utilized for alcoholysis reaction to obtain a macromolecular initiator. Then, a simple amphiphilic diblockpolymer (mPEG-PDMAEMA) based on the initiator and dimethylaminoethyl methacrylate was synthesized through the atomic transfer radical polymerization (ATRP) method. The structures of the initiator and diblock polymer were accurately characterized using infrared spectrum and proton nuclear magnetic resonance spectroscopy (1H NMR). Cryo-transmission electron microscopy revealed the self-assembly of mPEG-PDMAEMA into vesicle-like structures in water. Upon injection of CO2into the solution, the tertiary amine structure within PDMAEMA underwent protonation, resulting in the mPEG-PDMAEMA adopting a hydrophilic structure. Consequently, the vesicles dissociated and dispersed, forming a network-like structure in water. The protonation phenomenon was confirmed by 1H NMR, as evidenced by the shifting of alkyl hydrogen atoms near nitrogen atoms toward downfield positions.

The lunar surface and its deep layers contain abundant resources and valuable information resources, the exploration and exploitation of which are important for the sustainable development of the human economy and society. Technological exploration and research in the field of deep space science, especially lunar-based exploration, is a scientific strategy that has been pursued in China and worldwide. Drilling and sampling are key to accurate exploration of the desirable characteristics of deep lunar resources. In this study, an in-situ condition preserved coring (ICP-Coring) and analysis system, which can be used to test drilling tools and develop effective sampling strategies, was designed. The key features of the system include: (1) capability to replicate the extreme temperature fluctuations of the lunar environment (−185 to 200 °C) with intelligent temperature control; (2) ability to maintain a vacuum environment at a scale of 10−3Pa, both under unloaded conditions within a ϕ580 mm × 1000 mm test chamber, and under loaded conditions using a ϕ400 mm × 800 mm lunar rock simulant; (3) application of axial pressures up to 4 MPa and confining pressures up to 3.5 MPa; (4) sample rotation at any angle with a maximum sampling length of 800 mm; and (5) multiple modes of rotary-percussive drilling, controlled by penetration speed and weight on bit (WOB). Experimental studies on the drilling characteristics in the lunar rock simulant-loaded state under different drill bit-percussive-vacuum environment configurations were conducted. The results show that the outgassing rate of the lunar soil simulant is greater than that of the lunar rock simulant and that a low-temperature environment contributes to a reduced vacuum of the lunar-based simulated environment. The rotary-percussive drilling method effectively shortens the sampling time. With increasing sampling depth, the temperature rise of the drilling tools tends to rapidly increase, followed by slow growth or steady fluctuations. The temperature rise energy accumulation of the drill bits under vacuum is more significant than that under atmospheric pressure, approximately 1.47 times higher. The real-time monitored drilling pressure, penetration speed and rotary torque during drilling serve as parameters for discriminating the drilling status. The results of this research can provide a scientific basis for returning samples from lunar rock in extreme lunar-based environments.

Introduction: Over the past decade, numerous studies have described the types of pathogens and their antibiotic resistance patterns in patients with burn injuries in China; however, the findings have generally been inconsistent. We conducted a literature search and meta-analysis to summarize the infection spectra and antimicrobial resistance patterns in patients with burn injuries. Methods: We searched the PubMed, Embase, Web of Science, China National Knowledge Infrastructure, China Biomedical Literature, Wanfang, and Weipu databases for relevant articles published between January 2010 and December 2023. The DerSimonian–Laird random-effects model was used to estimate the proportions and 95% confidence intervals (CIs) of pathogens among Chinese patients with burn injuries. Meta-regression analyses were performed to explore differences in the proportions of pathogens among different subgroups and their resistance patterns. This study was registered with PROSPERO (CRD42024514386). Results: The database searches yielded 2017 records; after removing duplicates and conducting initial screening, 219 articles underwent full-text screening. Ultimately, 60 studies comprising a total of 62,819 isolated strains reported the proportions of pathogens in patients with burn injuries and were included in this meta-analysis. Meta-analyses were conducted on 18 types of pathogens. The most common pathogens causing infections in Chinese patients with burn injuries were Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae, and Staphylococcus epidermidis. Similar results were observed in the subgroup analysis focusing on wound infections. Since 2015, there has been a significant decrease in the proportion of Pseudomonas aeruginosa(R2= 4.89%) and a significant increase in the proportion of Klebsiella pneumoniae(R2= 9.60%). In terms of antibiotic resistance, there has been a significant decrease in the resistance of Staphylococcus aureusto multiple antibiotics and an increasing trend in the resistance of Klebsiella pneumoniae. Conclusions: We systematically summarized the epidemiological characteristics and antibiotic resistance patterns of pathogens among individuals suffering from burns in China, thus providing guidance for controlling wound infections and promoting optimal empirical antimicrobial therapy. The observed high levels of antibiotic resistance underscore the need for ongoing monitoring of antibiotic usage trends.

C23H30O5, orthorhombic, P212121(no. 19), a= 9.5489(10) Å, b= 11.1430(10) Å, c= 18.8931(10) Å, V= 2010.29(3) Å3, Z= 4, Rgt(F) = 0.0293, wRref(F2) = 0.0763, T= 100.0(2) K.

C20H26O5, orthorhombic, P212121(no. 19), a= 5.2825(10) Å, b= 13.0652(2) Å, c= 26.4176(4) Å, V= 1823.26(5) Å3, Z= 4, Rgt(F) = 0.0338, wRref(F2) = 0.0821, T = 150 K. CCDC No.: 2377464.

The quality and safety of agricultural soil are the foundation of crop production, and the traceability of heavy metals (HMs) is a prerequisite for effective contamination control. In order to identify the risks and contaminationc sources of HMs in agricultural soils, a combination of multivariate statistics, geographic information system (GIS), and positive matrix factorization model (PMF) was used to identify sources of contamination in agricultural soils of Tongren City; besides, potential ecological and health risks specific to the contaminant sources were calculated on the basis of contribution from variables. The results indicated that the mean values of Cd (0.34 ± 0.17 mg/kg), Cu (30.76 ± 10.94 mg/kg), Hg (2.51 ± 4.71 mg/kg), Pb (36.06 ± 35.95 mg/kg), and Zn (112.10 ± 62.29 mg/kg) in agricultural soil were significantly greater than the local background values. The HMs content of agricultural soil performed a clustering trend in space, showing a positive correlation. High values of soil Hg content were concentrated in the eastern areas of the Tongren City, where mining activities were intensive, and high values of soil Cd content were mainly found in the central areas. The HMs in the agricultural soil were generally at moderately contaminated levels. Sources of pollution for HMs were identified as smelting source (39.7%), natural source (33.2%), agricultural source (15.8%), and mining source (11.3%). Agricultural soils in the study area were generally at a high potential ecological risk level. The health risks for children were high level and required attention. The mining and smelting source were the main risk sources of the study area. In this study, a comprehensive methodology for risk assessment based on pollution sources was proposed to provide a valuable reference for risk prevention and control of HMs in agricultural soils.

In sparse linear array (SLA) design, mutual coupling (MC) is a nonnegligible metric, while both MC effects and lower degrees of freedom (DOFs) can reduce the accuracy of direction-of-arrival (DOA) estimation. To mitigate the MC effect and achieve more unique DOFs, we propose two novel enhanced dilated nested array (EDNA) configurations, named EDNA-I and EDNA-II. In contrast to most advanced SLA configurations, the proposed EDNA-I and EDNA-II have fewer sensor pairs at smaller separations and thus have better robustness to MC effects. In addition, their sensor locations and DOFs can be derived as simple explicit expressions. Theoretical proofs and numerical simulations show that the proposed EDNA-I and EDNA-II have superior performance in terms of DOFs and weight function and also effectively suppress the MC effect, which in turn exhibits better DOA estimation performance in the presence of MC.

As a basic optical filter configuration, A Fabry-Perot (FP) resonator has found extensive applications in laser excitation, sensing, and optical communication. Here, we propose an on-chip fully tunable silicon photonic FP filter based on multi-mode waveguide. The proposed FP filter has a low-loss multi-mode rib waveguide and two Sagnac loop mirrors (SLMs), which is of help to achieving a high Q-factor. By controlling the voltages applied to the micro-heaters placed on top of the multi-mode waveguide and directional couplers of the SLMs, the effective length of the cavity and the reflectivity of the SLMs can be tuned, leading to the fully tuning in resonance wavelength and bandwidth. A chip is designed and fabricated, which has a narrow passband of 2.7 pm, corresponding to a loaded Q-factor of $0.6\times 10^{{6}}$ . By controlling the voltages, its resonance wavelength can be tuned in a range of 0.27 nm, and the 3-dB bandwidth can be tuned from 2.0 to 25.1 pm. With the use of the fabricated chip, a fully tunable microwave photonic filter is experimentally demonstrated. The proposed FP filter has a high Q-factor and flexible tunability, which holds potential in the applications of microwave photonic signal processing systems and optical communication networks.

We used the molecular dynamics method to simulate the behavior of potassium perfluorohexanesulfonate (KPFOS) in water/gas system. The results indicate that PFOS−can spontaneously migrate to the water/gas interface and form a layered structure with hydrophobic tail chains facing the gas phase and hydrophilic sulfonic acid groups immersed in the water phase, while some PFOS−molecules within the solution formed spherical micelles. Both the number density and charge density distributions confirm that PFOS−and K+are mainly distributed at the water/gas interface, and a small amount of PFOS−and K+are distributed in the bulk solution. Based on the results of radial distribution function, the probability of K+appearing near oxygen atoms in PFOS−is very high due to electrostatic attraction. Based on the IGMH analysis, the oxygen atoms in PFOS−can form multiple hydrogen bonds with adjacent water molecules, while there is only weak van der Waals interaction between K+and water molecules.

Ammonia borane (AB) is considered to be a promising chemical hydrogen storage material with high hydrogen storage density (19.6%), which can release three molar equivalents of hydrogen through catalytic hydrolysis at room temperature. However, AB releases hydrogen slowly in water, it is necessary to develop highly active metal nanocatalysts to accelerate the process of hydrolysis. This article provides an overview of the synthesis and characterization methods of ammonia borane, the mechanism of hydrolysis and catalytic hydrogen production using the unique dihydrogen key in the ammonia borane structure, and the various factors that affect the hydrogen release performance of AB.

C15H22O3, orthorhombic, P212121(no. 19), a= 7.4754(10) Å, b= 11.1287(2) Å, c= 16.1412(3) Å, V= 1,342.81(4) Å3, Z= 4, Rgt(F) = 0.0344, wRref(F2) = 0.0921, T = 99.98(11) K.

Gut barrier disruption is a key event in bridging gut microbiota dysbiosis and high-fat diet (HFD)-associated metabolic disorders. However, the underlying mechanism remains elusive. In the present study, by comparing HFD- and normal diet (ND)-treated mice, we found that the HFD instantly altered the composition of the gut microbiota and subsequently damaged the integrity of the gut barrier. Metagenomic sequencing revealed that the HFD upregulates gut microbial functions related to redox reactions, as confirmed by the increased reactive oxygen species (ROS) levels in fecal microbiota incubation in vitroand in the lumen, which were detected using in vivofluorescence imaging. This microbial ROS-producing capability induced by HFD can be transferred through fecal microbiota transplantation (FMT) into germ-free (GF) mice, downregulating the gut barrier tight junctions. Similarly, mono-colonizing GF mice with an Enterococcusstrain excelled in ROS production, damaged the gut barrier, induced mitochondrial malfunction and apoptosis of the intestinal epithelial cells, and exacerbated fatty liver, compared with other low-ROS-producing Enterococcusstrains. Oral administration of recombinant high-stability-superoxide dismutase (SOD) significantly reduced intestinal ROS, protected the gut barrier, and improved fatty liver against the HFD. In conclusion, our study suggests that extracellular ROS derived from gut microbiota play a pivotal role in HFD-induced gut barrier disruption and is a potential therapeutic target for HFD-associated metabolic diseases.

Drinking water treatment residuals (DWTRs) are complex mixtures of organic and inorganic phases generally disposed of as waste materials. However, their strong sorptive properties could be further exploited to immobilize contaminants. To characterize these materials, we applied a range of analytical techniques to a set of aluminum-based DWTRs. We determined surface areas, elemental compositions using CHNS analysis and X-ray fluorescence (XRF), performed thermogravimetric analyses paired with mass spectrometry (TGA-MS), and used synchrotron-based methods: X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). Elemental analyses and specific surface area measurements – that vary between 7.23 ± 0.03 and 197.6 ± 0.9 m2g−1– indicate that non-coagulant additives must play an important role in controlling sorption. High resolution powder XRD reveals the presence of only a few crystalline minerals mostly derived from source waters or additives. Fe was detected by XRF in all samples, whereas Mn was present in significant levels in samples with potassium permanganate as additive. The chemical speciation of these elements was characterized by performing spectral decompositions of XAS spectra. The spectral features of Fe are consistent with iron(iii) oxides/hydroxides and structural iron in clays. On the other hand, Mn is predominantly present under its reduced form, Mn(ii).

We demonstrate a multifunctional optical spectral shaper on a silicon photonic chip. The proposed structure is composed of a tunable microring resonator (MRR) and three tunable Sagnac loop mirrors (SLMs), which can be regarded as a large SLM incorporating an MRR-coupled Fabry–Perot (FP) cavity. To realize flexible tuning, thermo-optically tunable Mach-Zehnder interferometer (MZI) couplers are used to replace conventional directional couplers with fixed coupling coefficients. By controlling the tunable MZI couplers, the proposed structure can be reconfigured as various functional structures including an all-pass MRR with tunable coupling regime, a tunable FP cavity, an SLM incorporating FP cavity, and an MRR-coupled FP cavity. This flexible reconfiguration allows for multifunctional optical spectral shaping including tunable comb filtering, Fano and EIT-like resonances. In particular, the complementary flat-top comb filtering responses can be theoretically obtained in the two ports of this device with same free spectral range (FSR) value, which enable the (de)interleaver operation. The experimental results show that the implemented all-pass MRR has a maximum extinction ratio (ER) of 38.9 dB and the corresponding quality factor is 6.5×104. The comb filter based on configured FP cavity can be switched from narrowband response (0.06 nm) to wideband flat-top response (0.23 nm), with ERs up to 10.6 dB and 22 dB, respectively. Moreover, a dynamic conversion between Lorentz, EIT, and Fano resonance line shapes based on the coupled resonant system can be realized. The demonstrated integrated device holds great potential for various applications such as filtering and switching in optical wavelength-division multiplexing (WDM) communication networks.

Although three-dimensional metal halide perovskite (ABX3) single crystals are promising next-generation materials for radiation detection, state-of-the-art perovskite X-ray detectors include methylammonium as A-site cations, limiting the operational stability. Previous efforts to improve the stability using formamidinium–caesium-alloyed A-site cations usually sacrifice the detection performance because of high trap densities. Here we successfully solve this trade-off between stability and detection performance by synergistic composition engineering, where we include A-site alloys to decrease the trap density and B-site dopants to release the microstrain induced by A-site alloying. As such, we develop high-performance perovskite X-ray detectors with excellent stability. Our X-ray detectors exhibit high sensitivity of (2.6 ± 0.1) × 104μC Gyair−1cm−2under 1 V cm−1and ultralow limit of detection of 7.09 nGyairs−1. In addition, they feature long-term operational stability over half a year and impressive thermal stability up to 125 °C. We further demonstrate the promise of our perovskite X-ray detectors for low-bias portable applications with high-quality X-ray imaging and monitoring prototypes.

The regulation of photosynthetic machinery with a nonoxidative approach is a powerful but challenging strategy for the selective inhibition of bloom-forming cyanobacteria. Acetylacetone (AA) was recently found to be a target-selective cyanocide for Microcystis aeruginosa, but the cause and effect in the studied system are still unclear. By recording of the chemical fingerprints of the cells at two treatment intervals (12 and 72 h with 0.1 mM AA) with omics assays, the molecular mechanism of AA in inactivating Microcystis aeruginosawas elucidated. The results clearly reveal the effect of AA on ferredoxin and the consequent effects on the physiological and biochemical processes of Microcystis aeruginosa. In addition to its role as an electron acceptor of photosystem I, ferredoxin plays pivotal roles in the assimilation of nitrogen in cyanobacterial cells. The effect of AA on ferredoxin and on nonheme iron of photosystem II first cut off the photosynthetic electron transfer flow and then interrupted the synthesis of adenosine triphosphate (ATP) and reduced nicotinamide adenine dinucleotide phosphate (NADPH), which ultimately might affect carbon fixation and nitrogen assimilation metabolisms. The results here provide missing pieces in the current knowledge on the selective inhibition of cyanobacteria, which should shed light on the better control of harmful blooms.

During the production process of high temperature and high pressure gas well, high temperature fluids are produced from the formation. The change of wellbore temperature and pressure, due to the change of production, has an important impact on the production tubular column, which threatens the safety of the completion tubular column and the integrity of the wellbore. A single-phase gas transient flow temperature–pressure​ coupling mathematical model is developed for the fluid in the tubular column during gas well production, and the pressure and temperature distribution patterns of the gas in the tubular column during gas well production are obtained, and the influence of production rate on the temperature–pressure distribution in the tubular column during gas well production is analyzed. The coupled temperature–pressure model takes into account the mutual influence of temperature and pressure during the transient flow of gas in the column, and the comparison with the measured data in the field and the calculation results of the analytical model shows that the coupled model has higher accuracy. The model will provide theoretical support for the selection and optimal design of completion production tubular tools.

The main zone of production of Sinian gas reservoirs in the Sichuan Basin (China) is the Deng 4 member of the Gaoshiti–Moxi structure. In the Deng 4 member, the rock type is mostly dolomite, and the main types of storage space are brecciated interporosity and large-scale interporosity characterized by low porosity and low permeability (average porosity: 3.21%, average permeability: 2.19 mD). In the Gaoshiti structure of the Deng 4 member gas reservoir, annual gas production of 60 billion cubic meters has been realized using differential segmented acid fracturing stimulation technology. However, with development of the Moxi structure, such technology is unable to adapt the reservoir because it requires continuous optimization according to reservoir characteristics. To provide effective support for optimization of reservoir stimulation technology, this study performed experiments using a large-scale true triaxialacid fracturing model. On the basis of the simulation of the reservoir reconstruction process, optimization of the process was investigated, an optimization scheme was proposed, and a field test was performed. The results, which indicated that gelling acid fracturing technology can effectively improve the stimulation effect of the Deng 4 member of the Moxi gas reservoir and substantially increase single-well production, could provide technical support for enhanced production of the Gaoshiti–Moxi gas reservoir.

The deformation and damage of soft rock roadways in karst mountainous area is serious, which greatly restricts the safe and efficient mining of coal resources. To explore the instability mechanism of soft rock roadway under the influence of mining, the 226 rail cross-cut of Shanjiaoshu Coal Mine in China was taken as an engineering background. The methods of field monitoring and drilling imaging were adopted to analyze the roadway failure characteristics. In addition, the distributions of the plastic zone, surface displacement, and fracture fractal evolution characteristics of the surrounding rock for different stress wave peak and stress wave frequency are compared and analyzed using UDEC software. Then, the combined support scheme of “secondary strong bolting and grouting” is proposed to control the severe deformation of the roadway. The primary support mainly adopts short hollow grouting anchor cable to strengthen the shallow broken surrounding rock within 0–3 m. The secondary reinforced support adopts long hollow grouting anchor cable or constant resistance large deformation anchor cable to fully mobilize the bearing capacity of deep surrounding rock and to ensure the long-term stability of the roadway. On-site monitoring showed that the scheme could effectively control the severe deformation of the roadway, which also provided a reference for other similar roadway support.

Carbonaceous material-activated persulfate (PS) has shown great potential for in-situ groundwater remediation. Herein, original coconut shells were treated via a multistep process to obtain activated carbon denoted as AC700, which was used to efficiently activate PS for the degradation of naphthalene (NAP). Compared with other carbonaceous materials, the AC700 showed an excellent activation performance, high reusability, and easy recovery by secondary pyrolysis. More importantly, the main functional active sites of AC700 and its corresponding activation mechanism were comprehensively revealed. The activation ability of AC700 was related to its electron exchange capacity of functional groups and electrical conductivity of graphite-like structure. In the AC700/PS system, the coexistence of free radical and non-free radical pathways produced multi-active species that synergistically degraded NAP. Encouragingly, the AC700/PS system exhibited excellent anti-interference ability and satisfactory activation stability in spiked natural groundwater. This study will further facilitate the development of the metal-free catalyst/PS system as a new technological strategy for in-situ remediation of groundwater.

Selective inhibition of photosynthesis is a fundamental strategy to solve the global challenge caused by harmful cyanobacterial blooms. However, there is a lack of specificity of the currently used cyanocides, because most of them act on cyanobacteria by generating nontargeted oxidative stress. Here, for the first time, we find that the simplest β-diketone, acetylacetone, is a promising specific cyanocide, which acts on Microcystis aeruginosathrough targeted binding on bound iron species in the photosynthetic electron transport chain, rather than by oxidizing the components of the photosynthetic apparatus. The targeted binding approach outperforms the general oxidation mechanism in terms of specificity and eco-safety. Given the essential role of photosynthesis in both natural and artificial systems, this finding not only provides a unique solution for the selective control of cyanobacteria but also sheds new light on the ways to modulate photosynthesis.

Low-cost and high-performance catalyst is crucial for hydrogen generation via the hydrolysis of ammonia borane (NH3BH3, AB) as a chemical hydrogen storage material. In this work, Co-CeOxnanocomposites supported on graphene (Co-CeOx/graphene) were prepared through a facile impregnation and chemical reduction method and used as a catalyst in the hydrolytic dehydrogenation of ammonia borane. The results indicate that the as-prepared Co-CeOx/graphene nanocomposite exhibits superior catalytic activity and recycling stability in the hydrolysis of ammonia borane, owing to the ultra-fine size of Co-CeOxparticles, the strong synergistic electronic effect between Co and CeOx, as well as the strong metal-support interaction between Co-CeOxand graphene. For the hydrolysis of ammonia borane over the optimized Co-CeOx/graphene catalyst, the turnover frequency (TOF) reaches 45.1 min−1, with the activation energy (Ea) of 39.5 kJ/mol; such a TOF value is 12 times and 9 times higher than those over Co and Co/graphene, respectively, also much higher than those reported for most noble-metal-free catalysts.

Electrospinning carbon nanofibers with one-dimensional nanostructures have enormous potential for electronic applications owing to their flexibility, electrical conductivity, high surface area and attractive structure. In this paper, porous nitrogen-doped carbon nanofiber membranes with chemical crosslinking structure (PNCNMs-CC) were prepared for lithium-ion batteries anodes by crosslinking treatment and carbonization process using polyimide as precursor, melamine as nitrogen source and ethyl orthosilicate as pore-forming agent. The heightened nitrogen content synergizes with the augmented specific surface area, engendering a striking electrochemical enhancement. Rich pore structure provides more active sites. When utilized as a binder-free, current collector-free anode, PNCNMs-CC shows an excellent rate performance and long cycle stability. The first discharge specific capacity of PNCNMs-CC delivered 710 mAh g−1at 50 mA g−1. After 1000 cycles at a high current density of 1 A g−1, PNCNMs-CC shows 88 % capacity retention, demonstrating a promising candidate as the flexible anodes for high-performance energy storage devices.

ABSTRACTDust from construction field is one of sources for the atmosphere particulate pollution. In this study, a solidifying material, modified polyvinyl alcohol (MPA), is used to control the dust from soil. The controlling efficiency of the MPA is evaluated based on its anti-wind and anti-rain erosion performance under different conditions such as soil types, spraying amount of MPA, slope morphologies (gradients and unevenness), and treated time. Results indicate that the MPA can bind well with the soil particles and it is able to strengthen the integrity of the surface. Soil treated with MPA exhibits good anti-wind effects, and PM10and PM2.5in environment do not increase even under a nine-grade wind erosion. Soil treated with MPA can maintain the surface integrity under a rainstorm, and there are no erosion traces and mud after rain erosion. The application of MPA has no limitation in terms of soil type, soil slope, and surface morphology, and thus, it has a wide applied prospect in engineering.Implications:In order to solve the air pollution problems existing on construction sites in densely populated areas, MPA optimizes a kind of environmental agent to treat, which does not affect the later use of soil. The applicability effect was verified from the perspective of anti-wind and anti-rain erosion doubly. Research results not only can provide data support for the construction management, but also help to promote the civilization and ecological benefit of construction.

•Two types of abnormal welding condition: edge welding (EW) and initial gap (IG), are taken into consideration to verify the validity of resistance and displacement based adaptive output tracking control strategies.•Even if the dynamic resistance or electrode displacement signal of the weld under EW and IG conditions coincides with that of the standard condition, their weld properties are still different.•The use of resistance-based tracking control strategy would reduce the welding current under EW and IG conditions, and lead to a decline of the nugget size and tensile-shear strength.•The displacement-based tracking control strategy works well in EW and IG conditions of slight level and enhances the nugget size and tensile-shear strength. However, it may raise the expulsion risk when the disturbance is too severe.

Obesity affects more than 650 million individuals worldwide and is a well-established risk factor for the development of hepatocellular carcinoma (HCC). Oxidative stress can be considered as a bona fide tumor promoter, contributing to the initiation and progression of liver cancer. Indeed, one of the key events involved in HCC progression is excessive levels of reactive oxygen species (ROS) resulting from the fatty acid influx and chronic inflammation. This review provides insights into the different intracellular sources of obesity-induced ROS and molecular mechanisms responsible for hepatic tumorigenesis. In addition, we highlight recent findings pointing to the role of the dysregulated activity of BCL-2 proteins and protein tyrosine phosphatases (PTPs) in the generation of hepatic oxidative stress and ROS-mediated dysfunctional signaling, respectively. Finally, we discuss the potential and challenges of novel nanotechnology strategies to prevent ROS formation in obesity-associated HCC.

Passivating contacts for silicon solar cells can be fabricated by depositing a layer of intrinsic amorphous silicon (a-Si) by the plasma-enhanced chemical vapor deposition (PECVD) onto an oxidized silicon wafer, followed by a thermal POCl3 diffusion process. This article describes the influence of the main PECVD parameters, power and pressure, on the electrical performance of such phosphorus-doped polysilicon (doped-Si/SiOx) passivating contacts. We characterize their properties in terms of the passivation quality and carrier selectivity for different PECVD powers and pressures. The deposition power settings from 350 to 800 W are tried, the highest iVoc value of 721 mV is achieved at a power of 500 W. The higher deposition powers (≥650 W) lead to blistering issues and possible interface damage, while a lower deposition power (350 W) leads to incomplete decomposition of the precursor gas, resulting in a lower passivation quality. Meanwhile, the power has a marginal impact on the contact resistivity. On the other hand, the deposition pressure has only a slight impact on the passivation quality, while significant changes are observed on the contact resistivity. A lower pressure (0.1 mbar) leads to a higher contact resistivity, while the low and consistent contact resistivity values of 5.8 mΩ·cm2 are obtained at the pressures above 0.2 mbar.

Silicon (Si) material is considered the most promising ideal anode material due to its highest theoretical specific capacity of 4200 mAh g−1. However, the large volume changes during the lithiation-delithiation process lead to electrode structure collapsed failure and hinder silicon anode application. To inhibit the volume expansion of silicon anode materials, this paper focuses on the surface modification of silicon-based thin film anode materials. Through the combination of plasma enhanced chemical vapor deposition technology (PECVD) and surface coating modification technology, sodium alginate (SA) coating is introduced on the surface of amorphous Si thin film to obtain Si/SA composite with good cycle performance. Furthermore, by constructing carbon nanotubes on the SA coating layer, Si/SA-CNTs composite was successfully prepared. The initially discharge specific capacity of Si/SA-CNTs is 3716 mAh g−1, and the discharge specific capacity is 2028 mAh g−1after 200 cycles at 0.5C (1C = 4.2 A g−1). It increased by 1413 mAh g−1compared with pure Si thin film. At the same time, its discharge specific capacity at 10C is 1726 mAh g−1, showing excellent rate performance. This surface coating modification helps relieve the stress and strain during the charge/discharge process. Meanwhile, the conductive structure enhances the transport of electrons and ions, which effectively improves the electrochemical performance of the Si thin film.

Weld expulsion is a universal problem during resistance spot welding (RSW) process and has potential damage to welding products and surrounding facilities. This study presents a new approach to the online evaluation of expulsion intensity using the amount of molten metal ejected during the expulsion. Through the newly developed multi-sensor monitoring and high-speed camera system, instantaneous features of process signals involving dynamic resistance, electrode force, and electrode displacement are simultaneously monitored and comparatively studied. The experimental results show that the amount of sudden decrease in the force and displacement signals is proportional to the weight of the expelled metal, but no apparent relationship is observed between the sudden resistance drop and the expulsion severity. Based upon further analysis, the abrupt change of electrode force is proven an optimal feature to precisely assess the magnitude of expulsion for a servo gun system. After calibration, the error of expulsion estimation could be limited to ±16.8 mg (±2σ) at a 95% confidence level, and the accuracy is robust to varying workpieces ranging from low carbon steel to high strength steel. This study may pave the way to online control the expulsion to the minimum level.