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A solid phase microextraction fiber (SPME) with gold nanoparticles coatings (AuNPs) was prepared based on stainless-steel fiber by chemical deposition. In order to greatly increase the specific surface area of the stainless-steel fiber, the porous fiber were formed by hydrofluoric acid treatment and aqua regia-dopamine treatment after AuNPs coating. Thus, the porous gold coated SPME with large specific surface area, strong bonding and controllable thickness were prepared. Scanning electron microscopy (SEM) and elements analysis were used to characterize. Under the optimized conditions, the prepared fibers exhibited good precision, wide linear ranges, acceptable recoveries, and low limits of detection for lamotrigine. The results verified that this novel coating was a promising sorbent for extraction and trace analysis of lamotrigine in complex matrixes.

The onset and progression of many cancers, including gastric cancer (GC), are strongly influenced by cell senescence. Numerous studies have demonstrated that long non-coding RNA (lncRNA) impacts cell senescence, thus affecting cancer progression. However, it is not possible to develop a relevant predictive model for GC owing to the absence of a cell senescence-linked lncRNA. Since lncRNAs are linked to cellular senescence, the goal of this work was to create a prognostic signature for stomach adenocarcinoma (STAD) patients utilizing these lncRNAs.Through the Pearson correlation, variance, and univariate Cox regression analyses, the cellular senescence lncRNAs that were related to the disease prognosis could be successfully identified. Using the least absolute shrinkage and selection operator (LASSO) regression algorithm, a predictive model that utilized the 11 cellular senescence-linked lncRNAs was constructed. Kaplan-Meier (KM) survival and the receiver operating characteristic (ROC) curve analyses, were employed for assessing the prognostic performance of the proposed model. In addition, ESTIMATE analysis of the low- and high-risk subtypes for the infiltration of various immune cells was carried out. Additionally, the CIBERSORT algorithm was utilized for investigating the infiltration status of numerous immune cells in both groups, while the expression of the immune checkpoint genes in the two groups, was also determined.In this study, a new prognostic model was constructed using 11 cellular senescence-related lncRNAs. The findings revealed that the OS status of the patients in the low-risk group (category) was significantly higher compared to the high-risk category (P0.001). The 1-year ROC-area under the curve (AUC) values for the risk score in the training group was 0.714, while the AUC value for the test and comprehensive groups were recorded to be 0.666 and 0.695, respectively, which were obviously due to stage, grade, age, etc. And based on univariate [hazard ratio (HR): 1.435; P0.001; 95% confidence interval (CI): 1.295-1.589] and multivariate analyses (P0.001; 95% CI: HR: 1.387; 1.247-1.543), it was noted that risk scores were effectively employed as a patient-independent prognostic factor.Taken together, these results suggest that cellular senescence-related lncRNAs are likely to be valuable prognostic markers for GC. They also reflect the situation of the STAD immune microenvironment and may provide direction for future GC treatment.

A temperature-controlled electrochemical sensor was constructed based on a composite membrane composed of temperature-sensitive polymer poly (N-isopropylacrylamide) (PNIPAM) and carboxylated multi-walled carbon nanotubes (MWCNTs-COOH). The sensor has good temperature sensitivity and reversibility in detecting Dopamine (DA). At low temperatures, the polymer is stretched to bury the electrically active sites of carbon nanocomposites. Dopamine cannot exchange electrons through the polymer, representing an “OFF” state. On the contrary, in a high-temperature environment, the polymer shrinks to expose electrically active sites and increases the background current. Dopamine can normally carry out redox reactions and generate response currents, indicating the “ON” state. In addition, the sensor has a wide detection range (from 0.5 μM to 150 μM) and low LOD (193 nM). This switch-type sensor provides new avenues for the application of thermosensitive polymers.

The current synthesis methods of high-entropy alloy (HEA) thin-film coatings face huge challenges in facile preparation, precise thickness control, conformal integration, and affordability. These challenges are more specific and noteworthy for noble metal-based HEA thin films where the conventional sputtering methods encounter thickness control and high-cost issues (high-purity noble metal targets required). Herein, for the first time, we report a facile and controllable synthesis process of quinary HEA coatings consisting of noble metals (Rh, Ru, Pt, Pd, and Ir), by sequential atomic layer deposition (ALD) coupled with electrical Joule heating for post-alloying. Furthermore, the resulting quinary HEA thin film with a thickness of ∼50 nm and an atomic ratio of 20:15:21:18:27 shows promising potential as a platform for catalysis, exhibiting enhanced electrocatalytic hydrogen evolution reaction (HER) performances with lower overpotentials (e.g., from 85 to 58 mV in 0.5 M H2SO4) and higher stability (by retaining more than 92% of the initial current after 20 h with a current density of 10 mA/cm2 in 0.5 M H2SO4) than other noble metal-based structure counterparts in this work. The enhanced material properties and device performances are attributed to the efficient electron transfer of HEA with the increased number of active sites. This work not only presents RhRuPtPdIr HEA thin films as promising HER catalysts but also sheds light on controllable fabrication of conformal HEA-coated complex structures toward a broad range of applications. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) This work wassupported by the Agency for Science, Technology and Research (A*STAR) AME Individual Research Grant (IRG) A1983c0032. K.W.T. and L.W. acknowledge financial support from the Singapore Ministry of Education AcRF Tier 2 grant (MOET2EP 50221-0017).

Background. IQGAP3 has important function in cancer progression and has become a potential therapeutic target as a transmembrane protein. But its role in tumor immunity and pan-cancer was not systematically investigated. This study evaluated the potential role of IQGAP3 and clinical significance in pan-cancer through combined multiomics analysis. Methods. From Genotype Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) databases, transcriptomic datasets were first obtained, and from Gene Expression Omnibus (GEO), expression profiling microarray data were acquired and integrated to systematically assess the expression differences and prognostic relevance of IQGAP3 in pancreatic cancer. Immunohistochemical data were obtained from Human Protein Atlas (HPA) to assess IQGAP3 protein expression differences, and exome data from TCGA were used to analyze IQGAP3 expression in relation to tumor mutational burden (TMB), microsatellite instability (MSI), and mutation. Additionally, we also analyzed the relationship between IQGAP3 expression and immune checkpoints, mismatch repair (MMR), and IQGAP3 relationship with methylation and copy number variation based on expression profiles. Results. Microsatellite instability (MSI), immune checkpoints, mismatch repair (MMR), and tumor mutational burden (TMB) all closely interacted with IQGAP3 mRNA. In addition, detailed relationships between the immune microenvironment and IQGAP3 mRNA as well as immune cell CD4+ Th2 and myeloid-derived suppressor cells (MDSCs) were determined. Mechanistically, IQGAP3 was involved in cytoskeleton formation, T cell receptor signaling pathways, DNA damage, cell cycle, P53 pathway, Fc gamma R-mediated phagocytosis, and apoptosis. Conclusion. IQGAP3 could serve as an effective prognostic biomarker for pan-cancer immune-related therapy.

The efficiency of hydrogen gas generation via electrochemical water splitting has been mostly limited by the availability of electrocatalyst materials that require lower overpotentials during the redox reaction. Noble metals have been used extensively as electrocatalysts due to their high activity and low overpotentials. However, the use of single noble metal electrocatalyst is limited due to atomic aggregation caused by its inherent high surface energy, which results in poor structural stability, and, hence, poor electrocatalytic performance and long-term stability. In addition, using noble metals as electrocatalysts also causes the cost to be unnecessarily high. These limitations in noble metal electrocatalysts could be enhanced by combining two noble metals in a core-shell structure (e.g., Rh@Ir) as a thin film over a base substrate. This could significantly enhance electrocatalytic activity due to the following: (1) the modification of the electronic structure, which increases electrical conductivity; (2) the optimization of the adsorption energy; and (3) the introduction of new active sites in the core-shell noble metal structure. The current state-of-the-art employs physical vapor deposition (PVD) or other deposition techniques to fabricate core-shell noble metals on flat 2D substrates. This method does not allow 3D substrates with high surface areas to be used. In the present work, atomic layer deposition (ALD) was used to fabricate nanoparticle thin films of Rh@Ir and Rh@Pt in a core-shell structure on glassy carbon electrodes. ALD enables the fabrication of nanoparticle thin film on three-dimensional substrates (a 2D functional film on a 3D substrate), resulting in a significantly increased surface area for a catalytic reaction to take place; hence, improving the performance of electrocatalysis. The Rh@Pt (with an overpotential of 139 mV and a Tafel slope of 84.8 mV/dec) and Rh@Ir (with an overpotential of 169 mV and a Tafel slope of 112 mV/dec) core-shell electrocatalyst exhibited a better electrocatalytic performances compared to the single metal Rh electrocatalyst (with an overpotential of 300 mV and a Tafel slope of 190 mV/dec). These represented a 54% and a 44% improvement in performance, respectively, illustrating the advantages of core-shell thin film nanostructures in enhancing the catalytic performance of an electrocatalyst. Both electrocatalysts also exhibited good long-term stability in the harsh acidic electrolyte conditions when subjected to chronopotentiometry studies. Agency for Science, Technology and Research (A*STAR) Published version This research is supported by the Agency for Science, Technology, and Research (A*STAR) under A*STAR Project No: A1983c0032.

In this study, three types of biomass with different structures were selected to synthesize carbon matrix in a cathode of Li-S battery. The influence of the structure of raw biomass on microstructure, sulfur-loading amount, and electrochemical performance was investigated in detail. The results demonstrated that the catkin-derived porous carbon (CPC) inherited the 1D-structured morphology and exhibited the highest specific surface area (2033.09 m2/g), the largest sulfur loading (53.72%), and the highest initial discharge specific capacity (1369.52 mA h g−1) under 0.1 C. Comparatively speaking, the wrinkled cloth-like sakura petal–derived porous carbon showed a better capacity (1218.14 mA h g−1) but poor cycling performance. And the 3D network structure of bamboo-derived porous carbon (BPC) exhibited a relatively high capacity retention. These results demonstrated that the structural feature of biomass raw materials plays an important role in the microstructure and electrochemical performance of the carbon products.

Noble metal medium entropy alloy (MEA) thin films have recently attracted enormous research interests recently because of their great potential in the catalytic application. However, conventional bottom-up fabrication methods for MEA thin film such as magnetron sputtering face enormous challenges including precise control over film thickness and consumption of costly high-purity noble metal targets. Herein, a facile and tunable approach is developed coupling sequential atomic layer deposition (ALD) of noble metal layers with electric Joule heating (EJH) alloying process to grow platinum-iridium-palladium (PtIrPd) MEA thin films. The PtIrPd MEA thin film with a thickness of ≈20 nm and an atomic ratio of 35:35:30 is successfully fabricated. The effect of EJH processing temperature on the film morphology and structure evolution is investigated. ALD provides flexibility in the metal deposition sequence with meticulous thickness control and atomic composition precision, while the ultrafast EJH ramping/cooling rates promote homogeneous alloying of MEA combinations inhibiting phase separation. Furthermore, the integrated method circumvents a major obstacle of finding a common ALD temperature window for different noble metal precursors as well as opens new pathways for the controllable synthesis of multicomponent metal alloy thin films with potential catalytic, magnetic, and optical properties. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) Submitted/Accepted version Y.Z. and L.J. contributed equally to this work. The authors acknowledge the funding supported by the Agency for Science, Technology and Research (A*STAR), AME Individual Research Grant (IRG) A1983c0032. K.W.T. and L.W. acknowledges funding support from the Singapore Ministry of Education AcRF Tier 2 grant (MOET2EP 50221-0017).

The sulfonic acid group exhibits considerable ion affinity. The present work therefore synthesizes, a core-shell composite material having a sulfonated polyaniline shell, and a bamboo-derived porous carbon core loaded with sulfur. The thin, homogeneous shell has a thickness of approximately 20 nm. This composite is employed as a cathode material in Li-S batteries and the electrochemical properties of these devices are systematically investigated. This cathode (containing 64.0 wt% S) exhibits a higher initial discharge capacity (1484 mAh g−1 at 0.1 C), improved cycling stability (853 mAh g−1 after 100 cycles at 0.1 C), and remarkable rate performance (810.2, 682.7 and 353.0 mAh g−1 at 2, 3 and 5 C, respectively). These values are superior to those obtained using a polyaniline shell. Electrochemical impedance spectroscopy and density functional theory calculations are used to elucidate the internal mechanisms of the sulfonated polyaniline shell during cycling. The calculated results demonstrate that the shell possesses extremely high electron and Li ion conductivities, and so enhances the redox reaction kinetics during long-term cycling. It also physically confines and chemically anchors polysulfides, thus limiting the shuttle effect. This cathode design is expected to assist in the future commercialization of Li-S batteries.

It had been proven that carbon aerogel (CA) can effectively improve the conductivity of sulfur (S) and suppress the shuttle effect of polysulfides in Li-S batteries, due to its outstanding electrical conductivity and micropore-rich structure. However, the microstructure of CA was easy to collapse and shrink during carbonization, resulting in a dramatically drop in specific surface area and porosity. Herein, graphene nanosheets (GNs) were introduced in CA to reinforce the structural stability. As-prepared CA/GNs composites were fabricated from in-situ polymerization of resorcinol (R) and formaldehyde (F) in graphene oxide (GO) solution. It was found that the mass concentration of the GO solution had a significantly positive effect on hierarchical porous structure of the CA/GNs composites, which presented improve the electrochemical performances due to the combination of micro-, meso- and macro-pores. It is worth noting that the CA/GNs0.1 sample, obtained from 10 wt % GO solution, possessed the largest specific surface area of 665.477 m2 g−1 and the largest pore volume of 0.912 cm3 g−1. Especially, after incorporated with moderate amount of S (58.86 wt %), the CA/GNs0.1/S cathode exhibited the best electrochemical performances (initial discharging capacity of 1501 mAh g−1 at 0.1C and reversible capacities of 471 mAh g−1 after 100 cycles and 341 mAh g−1 after 500 cycles at 1C). This was attributed to the tunable hierarchical porous microstructure of the CA/GNs0.1 sample. Unfortunately, when increased the S content to 68.39 wt %, the electrochemical performance deteriorated in all aspects because of their sluggish reaction kinetics. These all results suggested that introducing GNs can feasibly enhance the performance of CA as matrix in Li-S batteries.

Lithium-sulfur (Li-S) battery with high theoretical capacity (1675 mAh g−1) and energy density (2600 Wh kg−1) is principally considered as an attractive alternative for state of art Li-ion batteries. In this study, a series of ternary composites were synthesized with bamboo-derived hierarchical carbon (BDC) to load S and flexible polyaniline (PANI) as a coating layer. The BDC/S composite was encapsulated by different weight percentage of PANI. The ternary PANI@BDC/S composites were characterized detailly by structural and electrochemical analysis and the results revealed that the PANI@BDC/S-20% electrode presented a thin and uniform PANI coating. As a cathode material for Li-S battery, the PANI@BDC/S-20% electrode exhibited the highest initial capacity (1463 mAh g−1 at 0.1C), outstanding long-life performance (366 mAh g−1 at 0.5C after 500 cycles), excellent rate property (527 mAh g−1 at 2C). The incremented gains were mainly because thin PANI coating was polymerized along with the porous carbon walls of BDC substrate, leaving an excellent hierarchical porous microstructure. The specific structure showed great physical confinement for polysulfides, meantime, the polysulfide migration could be restricted by heteroatom (N atom) doped on the PANI backbone. The soft and stable PANI shell reduce volume expansion during cycles, providing an integrated conductive framework for enhancing the electrochemical contact between S particles and carbon substrate. More important, the modified polar interface contributed to stable SEI formation. Such a novel design of cathode material demonstrated great potential for practical applications in Li-S batteries.

Palladium thin films have been grown by thermal atomic layer (ALD) process using Palladium (II) hexafluoroacetylacetonate (Pd(hfac)2) and O3 as the precursors without molecular hydrogen or formalin in a temperature range of 180–220 °C. The palladium films were deposited on sapphire (α-Al2O3, (0001)), silicon (Si, (111)) and silica (SiO2, (100)) substrates at a constant growth rate of about 0.25 Å per cycle. The metallic palladium films produced were highly uniform without fluorine contamination. The surface roughness was only 0.2 nm. The resistivity of the metallic palladium film at ∼25 nm in thickness deposited at 200 °C was around 63 μΩ cm. The morphology of Pd thin films on sapphire, silicon and silica surfaces revealed the island growth and these islands finally coalesced after applying 800 cycles. Thickness-controllable palladium films were obtained with shortened pulse time of both reactants (Pd(hfac)2 and ozone). Our work provides important guidelines for fabrication of metals by adjusting reaction parameters in thermal ALD process. Agency for Science, Technology and Research (A*STAR) The authors would like to acknowledge funding support from the Agency for Science, Technology and Research (A*STAR), AME Individual Research Grant (IRG) for this project. The Program of Huxiang Young Talents (2018RS3099). Natural Science Foundation of Hunan Province (2019JJ50097).

With the rapid development of China's socialist market economy, more and more people begin to pay attention to the development and utilization of new energy, and new energy has begun to attract people's attention. The main circuit structure and working principle of the most important inverter circuit in the whole photovoltaic power generation system are analyzed in detail, and the calculation method of the main components of the photovoltaic inverter circuit selected in this study is given and confirmed through simulation and experiment. When the main circuit of the whole photovoltaic inverter is analyzed and studied, in order to improve the output power of the whole circuit, the basic circuit structure is modified appropriately. The whole circuit uses high switching frequency, high voltage resistance IGBT, achieved the purpose of simplifying the whole circuit, and the overall efficiency of the circuit can be reduced, while ensuring the good output waveform of the whole circuit.

A nano-magnesium nickel oxide-mesoporous carbon/sulfur composites (Mg0.6Ni0.4O-MPC/S) was designed and prepared for lithium-sulfur (Li-S) batteries. With a specific surface area as high as 1001.2 m2 g−1 and a unique porous structure, MPC in the composites can not only absorb the polysulfides generated during charge-discharge process to slow down the shuttle effect, but provide Li+ with a transmission channel. Nano-Mg0.6Ni0.4O (40 nm) particles, as an additive fabricated by self-propagating high temperature synthesis, can promote chemical bond dissociation with polysulfides and accelerate the electrochemical reaction rate. The composites loaded with 59 wt% sulfur exhibit a high initial capacity of 1360 mAh g−1 at 0.1 C and 695 mAh g−1 after 100 cycles, proving that the synergistic effect between MPC and nano-Mg0.6Ni0.4O leads to good cycle stability of the batteries.

Lithium-sulfur (Li-S) battery processes high theoretical capacity (1675 mA h g−1) and energy density (2600 Wh kg−1), which was widely accepted as one of the most promising candidates for energy storage devices. In this presented study, bamboo-derived hierarchical porous carbon (BDPC) was adopted as a conducting substrate for containing S. Soft polystyrene (PS) and polyaniline (PANI), were prepared as coating layers. The main purpose is to figure out the specific roles that the polymer shells and the heteroatoms doped on polymer backbone play during cycles. The ternary products were characterized by structural analysis and electrochemical testing. The results indicate that, as compared to BDPC/S, the PS@BDPC/S electrode displays higher capacity retention during long-term cycles, especially at the high current rate. It is attributed to the integrated coating shell, which provides physical confinement and reserves spaces for restraining volume expansion. It is noted that the PANI@BDPC/S electrode presents a higher initial capacity, remarkable long-life performance, and excellent rate property. The outstanding performances are closely related to the nitrogen atom doped on PANI backbone, they provide not just abundant polar conducting sites for fast electron/Li-ion transport but strong chemical anchoring for restricting the migration of polysulfides. Therefore, our study poses a clearer understanding of the functionalized polymers used in Li-S battery.

Undoped and Fe-doped Zinc Oxide (ZnO) nanofibers were prepared by electrospinning method to investigate the effect of transition metal ion doping on the photocatalytic performance of ZnO. A variety of techniques were employed to characterize various properties of the fabricated nanofibers. It was realized that the crystallization of ZnO fibers was significantly improved by optimizing the sintering conditions. The results revealed that Fe-doping greatly improved the photocatalytic activity of ZnO owing to modified nanofibers morphology and the reduced optical bandgap. The ZnO nanofibers showed the optimum photocatalytic activity for 1.5% Fe-doping percentage which was attributed to the presence of maximum dopant ions in the ZnO matrix. The enhanced photocatalytic performance of ZnO could increase its scope of industrial and commercial applications.

Nitrogen and sulfur dual-doped graphene (NSG) synthesized by a simple and low-cost one-pot microwave assisted method is applied to immobilize sulfur by the mean of an in situ sulfur deposition approach. Images of scanning electron microscope (SEM) and transmission electron microscope (TEM) show that nano-sulfur (2–20 nm) is wrapped by the transparent NSG nanosheets with wrinkled and folded features. The application of X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) confirmed the structure and composition of the obtained nitrogen and sulfur dual-doped graphene/sulfur (NSG/S) composites as well. The heteroatom doping content was controlled by adjusting the amount of thiourea. The XPS analysis results indicate that pyridinic-N and pyrrolic-N are dominant among the product, thereby improving the cycle life of the lithium sulfur batteries. The NSG-4/S composites with sulfur loading of 68 wt% exhibits a remarkably higher reversible specific capacity of 1583 mAh g−1, impressive rate capability, splendid specific discharge capacity of 819 mAh g−1 at 0.1 C after 100 cycles and long cycle stability of 640 mAh g−1 after 200 cycles at 1 C.

In this work, graphene quantum dots/sulfur (GQDs/S) composite was prepared as cathode material for lithium sulfur (Li-S) batteries by a feasible chemical method. Multiple polar functional groups in GQDs can provide more active absorption sites to significantly strengthen the chemical absorption with polysulfides, suppressing the ‘shuttle effect’. In addition, the highly dispersed GQDs particles in the solution served as nucleation sites, the dissolved sulfur are reprecipitated around the GQDs, forming a dendritic interlaced network structure to prevent the aggregation of the sulfur, and further enhance the utilization of active substances. A high initial discharge capacity of 1125 mA h g−1 at 0.1C has been obtained in the GQDs/S cell, which is much higher than the initial discharge capacity of 658 mA h g−1 of GQDs/SR prepared by physical melting method. The superior performance of GQDs/S is attributed to the unique dendritic interlaced framework and multiple polar functional groups. The strong chemical effects between polar functional groups and polysulfides have been confirmed by the absorption experiment and DFT calculation. This work develops a new strategy in cathode material design for Li-S batteries.

The purpose of the present study has been to theoretically investigate the effect of boron doping on the diamond growth rate. The most frequently observed diamond surface planes (100), (111), and (110) were thereby carefully investigated using density functional theory calculations under periodic boundary conditions. It was shown that both the thermodynamic and kinetic aspects of the diamond growth process will be severely affected by the B dopant (as compared with the nondoped situations). More specifically, the results showed that B (positioned within the second atomic C layer) will cause an enhancement in the growth rate. On the other hand, the effect of B positioned in the other atomic C layers showed a decreased growth rate. These observations did not only correlate with experimental results but did also explain the anomalous variations in the diamond growth rate (i.e., either increase or decrease) with B doping.

Here, the hydroxyl content of reduced graphene oxide (rGO) is controlled by adjusting reduction time with l -ascorbic acid as reduction agent to study the effect on cathode performance of lithium sulfur batteries (LSBs). The results indicate that the hydroxyl content decreases from 35.8% to 17.9% with prolonging reduction time from 6 h to 48 h, and the C/O ratio increases. More importantly, it is demonstrated that the rGO with relatively low hydroxyl content within 36 h of reduction is more beneficial to enhance both the initial capacity and capacity retention as well as rate performance of LSBs, which is ascribed to the higher conductivity, stronger adsorption and relatively few reaction by-products with the decrease of hydroxyl content. However, when the reduction time is further prolonged to 48 h, the cathode performance deteriorates. As a result, rGO-36h/S electrode with the optimum hydroxyl content (19.2%) achieves an initial discharge capacity of 1340.9 mAh g−1, which still maintains 707.8 mAh g−1 over 100 cycles at 0.1C. This work may provide a guide for reducing GO when used as sulfur host material or matrix material of LSBs.