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Activating π-conjugated electron transfer in graphitic carbon nitride (g-C 3 N 4), not only enhances the absorption of solar light, but also breaks through energy barrier, sequentially leading to increased photocatalytic hydrogen production. However, g-C 3 N 4 is prone to agglomeration, wide bandgap, weak absorption of visible light, poor electrical conductivity and so on, which seriously restrict its photocatalytic performance, therefore activating π-conjugated electron transfer is confronted with great challenges. Herein, we show that activating π-conjugated electron transfer by breaking tri-s-triazine unit of g-C 3 N 4 through a simple one-step gas template method. As a result, the best performed CN-4 sample exhibits an outstanding hydrogen production rate of 1282 μmol h−1 g−1, which is 455% higher than that of the pristine g-C 3 N 4 (282 μmol h−1 g−1). Moreover, the density functional theory (DFT) calculations suggest that the original π-conjugated electron equilibrium system has been a significant transformation by C-doping. The results present a new direction of thought that utilizes π-conjugated electron transfer to enhance the photocatalytic hydrogen production by breaking tri-s-triazine unit. • A facile route can efficiently activate π-conjugated electron transfer in g-C 3 N 4. • π-conjugated electron transfer can adjust the electronic structure. • π-conjugated electron transfer contributes to enhanced photocatalytic H 2 generation. [ABSTRACT FROM AUTHOR]

Background: Peripheral blood immunomarkers are associated with prognosis in patients with solid tumors receiving chemotherapy or immunotherapy. In this study, the associations of circulating neutrophil‐to‐lymphocyte ratio (NLR), monocyte‐to‐lymphocyte ratio (MLR), and platelet‐to‐lymphocyte ratio (PLR), as well as their dynamic changes were investigated in relation to the efficacy of immunotherapy in patients with primary liver cancer. Methods: Comparisons were made between NLR, MLR, and PLR among individuals exhibiting disease control (defined as the best response of partial response [PR] or stable disease [SD]) and those with progressive disease (PD). Additionally, disease control rate (DCR), overall survival (OS), and progression‐free survival (PFS) were compared between individuals with different NLR, MLR, and PLR levels before initiating palliative immunotherapy. Furthermore, comparisons were made between patients with different alterations in the ratios at the second cycle of immunotherapy compared to baseline. These analyses were performed using univariate and multivariate approaches. A total of 119 Chinese patients with liver cancer who underwent immunotherapy were included in this study, which focused on hepatocellular carcinoma (HCC). Results: In cases with HCC (n = 104), the cutoffs of NLR, MLR, and PLR to differentiate treatment responders from nonresponders were 3.38, 0.28, and 227.18, respectively. Patients with the best response of PR or SD had significantly lower NLR and MLR. Patients with NLR <3.38 and those with MLR <0.28 significantly had longer OS and PFS than their counterparts, and those with PLR <227.18 had significantly longer PFS, both in overall patients and in various patient subgroups. Lower NLR, MLR, or PLR was associated with earlier BCLC stage, fewer metastatic sites, less frequent extrahepatic metastasis, or better performance status. For individuals who had an unfavorable baseline NLR ≥3.38, MLR ≥0.28, or a favorable baseline PLR <227.18 prior to first immunotherapy, a decrease in NLR, MLR, or PLR at Cycle 2 of immunotherapy was significantly associated with a higher DCR. Conclusions: Among patients with HCC who received immunotherapy, lower NLR, and MLR at baseline in overall patients were significantly associated with better disease control and more favorable survival outcomes (both OS and PFS), and lower PLR was significantly associated with longer PFS. The findings of this research may offer useful hints foranoptimized selection of patients with liver cancer who may benefit more from immunotherapy. [ABSTRACT FROM AUTHOR]

In this study, GX2 was applied as a new high-efficiency chalcopyrite depressant to selectively separate molybdenite from Cu-Mo sulfide ores. The flotation performance and its interaction mechanisms with chalcopyrite and molybdenite were investigated using single-mineral and artificial-mixed-ore flotation, contact angle measurements, zeta-potential measurements, infrared spectroscopy, and X-ray optoelectronic spectrum analysis. The results indicated that molybdenite could be selectively separated from chalcopyrite under the optimal flotation conditions of pH 9.0, 80 mg/L GX2, 20 mg/L kerosene, 10 mg/L MIBC, and a flotation time of 3 min, while the molybdenite and chalcopyrite recoveries were around 90% and 5%, respectively. It was confirmed that GX2 could save ten times the depressant dosage compared to that of the Na2S baseline to achieve a similar separation efficiency. The contact angle test, zeta potential, infrared spectrum, and XPS results show that GX2 may be adsorbed on the surface of chalcopyrite via chemical adsorption, and the hydrophilic substances formed change its hydrophobicity, whereas the effect on the floatability of molybdenite is small, resulting in the excellent separation efficiency of chalcopyrite and molybdenite via flotation. [ABSTRACT FROM AUTHOR]

The batch distillation is significant and flexible to separate liquid mixtures. However, it is usually energy intensive. The dividing‐wall column (DWC) is a promising and practical energy‐saving process intensification technology. The DWC for batch distillation (batch DWC) to separate benzene, toluene, and xylene mixtures was examined with composition and temperature control structures to verify its controllability. Besides, the batch DWC outperforms the conventional single‐column batch distillation and middle‐vessel batch distillation in terms of distillation time and energy consumption under the same conditions. In terms of more practical temperature control results, the batch DWC saves 63 % of energy compared with the conventional single‐column batch distillation and 47 % of energy compared with the middle‐vessel batch distillation. [ABSTRACT FROM AUTHOR]

Background: Vonoprazan, a novel acid-suppressive drug, is non-inferior to proton pump inhibitors (PPIs) for the management of gastric acid-related diseases. However, the safety of vonoprazan has not been systematically evaluated yet. Objectives: To elucidate the incidence and type of adverse events (AEs) in patients taking vonoprazan. Design: Systematic review and meta-analysis. Data sources and methods: PubMed, EMBASE, and Cochrane Library databases were searched for all studies reporting the safety of vonoprazan. The incidences of any AEs, drug-related AEs, serious AEs, AEs leading to drug discontinuation, and common AEs were pooled. Odds ratios (ORs) were calculated to compare the incidence of AEs between patients taking vonoprazan and PPIs. Results: Seventy-seven studies were included. The pooled incidences of any AEs, drug-related AEs, serious AEs, and AEs leading to drug discontinuation were 20, 7, 1, and 1%, respectively. The incidences of any AEs (OR = 0.96, p = 0.66), drug-related AEs (OR = 1.10, p = 0.44), serious AEs (OR = 1.14, p = 0.36), and AEs leading to drug discontinuation (OR = 1.09, p = 0.55) were not significantly different between patients taking vonoprazan and PPIs. In subgroup analyses, patients with peptic ulcer disease (PUD) had higher incidences of any AEs, serious AEs, and AEs leading to drug discontinuation than those with gastroesophageal reflux disease (GERD), Helicobacter pylori (H. pylori) infection, and artificial ulcer after gastric endoscopic submucosal dissection (ESD), but patients with H. pylori infection had a higher incidence of drug-related AEs than those with PUD, GERD, and artificial ulcer after gastric ESD. The incidence of AEs was higher in patients taking long-term use of vonoprazan than those taking short-term use of vonoprazan. Conclusion: Vonoprazan is well tolerated and shows similar safety compared to PPIs. The safety of vonoprazan may be primarily influenced by its indications and duration. Registration: PROSPERO CRD42022314982. [ABSTRACT FROM AUTHOR]

We report a synthetic strategy to link titanium‐oxo (Ti‐oxo) clusters into metal‐organic framework (MOF) glasses with high porosity though the carboxylate linkage. A new series of MOF glasses was synthesized by evaporation of solution containing Ti‐oxo clusters Ti16O16(OEt)32, linkers, and m‐cresol. The formation of carboxylate linkages between the Ti‐oxo clusters and the carboxylate linkers was confirmed by Fourier‐transform infrared (FT‐IR) spectroscopy. The structural integrity of the Ti‐oxo clusters within the glasses was evidenced by both X‐ray absorption near edge structure (XANES) and 17O magic‐angle spinning (MAS) NMR. After ligand exchange and activation, the fumarate‐linked MOF glass, termed Ti‐Fum, showed a N2 Brunauer–Emmett–Teller (BET) surface areas of 923 m2 g−1, nearly three times as high as the phenolate‐linked MOF glass with the highest BET surface area prior to this report. [ABSTRACT FROM AUTHOR]

We report a synthetic strategy to link titanium‐oxo (Ti‐oxo) clusters into metal‐organic framework (MOF) glasses with high porosity though the carboxylate linkage. A new series of MOF glasses was synthesized by evaporation of solution containing Ti‐oxo clusters Ti16O16(OEt)32, linkers, and m‐cresol. The formation of carboxylate linkages between the Ti‐oxo clusters and the carboxylate linkers was confirmed by Fourier‐transform infrared (FT‐IR) spectroscopy. The structural integrity of the Ti‐oxo clusters within the glasses was evidenced by both X‐ray absorption near edge structure (XANES) and 17O magic‐angle spinning (MAS) NMR. After ligand exchange and activation, the fumarate‐linked MOF glass, termed Ti‐Fum, showed a N2 Brunauer–Emmett–Teller (BET) surface areas of 923 m2 g−1, nearly three times as high as the phenolate‐linked MOF glass with the highest BET surface area prior to this report. [ABSTRACT FROM AUTHOR]

Background: Previous studies have shown that bone morphogenetic protein 9 (BMP9) is almost exclusively produced in the liver and reaches tissues throughout the body as a secreted protein. However, the mechanism of BMP9 action and its role in aging-associated liver injury and inflammation are still unclear. Results: Aging significantly aggravates acetaminophen (APAP)-induced acute liver injury (ALI). Increased expression of CCAAT/enhancer binding protein α (C/EBPα) and BMP9 was identified in aged livers and in hepatocytes and macrophages (MФs) isolated from aged mice. Further analysis revealed that excess BMP9 was directly related to APAP-induced hepatocyte injury and death, as evidenced by activated drosophila mothers against decapentaplegic protein 1/5/9 (SMAD1/5/9) signaling, an increased dead cell/total cell ratio, decreased levels of ATG3 and ATG7, blocked autophagy, increased senescence‐associated beta‐galactosidase (SA‐β‐Gal) activity, and a higher rate of senescence‐associated secretory phenotype (SASP) acquisition. In contrast, Bmp9 knockout (Bmp9−/−) partially alleviated the aforementioned manifestations of BMP9 overexpression. Moreover, BMP9 expression was found to be regulated by C/EBPα in vitro and in vivo. Notably, BMP9 also downregulated autophagy through its effect on autophagy-related genes (ATG3 and ATG7) in MΦs, which was associated with aggravated liver injury and SASP acquisition. Conclusions: In summary, the present study highlights the crucial roles played by C/EBPα-BMP9 crosstalk and provides insights into the interrelationship between hepatocytes and MΦs during acute liver injury. [ABSTRACT FROM AUTHOR]

Establishing the relationship between molecular structures and mechanical properties is of great significance for the structural design of vulcanised styrene-butadiene rubber (SBR). The molecular dynamics method was used to study the mechanical properties of cross-linked SBR with controlled network topology, and the corresponding molecular mechanism was analysed by the energy contribution during the stretching process. The results showed that the tensile stress of the end-linked network sample could be up to 20 times higher than that of the sample with dangling chains at an engineering strain of 1.4. Moreover, under the same fixed cross-linking degree, the tensile stress of the long-chain network sample was significantly higher than that of the short-chain network sample. This is because the molecular chains located in the main chain network will be highly oriented during the stretching process, while the proportion of highly oriented molecular chains is high in samples with end-linked networks or a large proportion of long chains. In addition, due to the limited relaxation of structural units, the end-linked network structure has good thermal stability. [ABSTRACT FROM AUTHOR]

Genetically modified (GM) soybeans provide a huge amount of food for human consumption and animal feed. However, the possibility of unexpected effects of transgenesis has increased food safety concerns. High-throughput sequencing profiling provides a potential approach to directly evaluate unintended effects caused by foreign genes. In this study, we performed transcriptomic analyses to evaluate differentially expressed genes (DEGs) in individual soybean tissues, including cotyledon (C), germ (G), hypocotyl (H), and radicle (R), instead of using the whole seed, from four GM and three non-GM soybean lines. A total of 3,351 DEGs were identified among the three non-GM soybean lines. When the GM lines were compared with their non-GM parents, 1,836 to 4,551 DEGs were identified. Furthermore, Gene Ontology (GO) analysis of the DEGs showed more abundant categories of GO items (199) among non-GM lines than between GM lines and the non-GM natural varieties (166). Results of Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that most KEGG pathways were the same for the two types of comparisons. The study successfully employed RNA sequencing to assess the differences in gene expression among four tissues of seven soybean varieties, and the results suggest that transgenes do not induce massive transcriptomic alterations in transgenic soybeans compared with those that exist among natural varieties. This work offers empirical evidence to investigate the genomic-level disparities induced by genetic modification in soybeans, specifically focusing on seed tissues. [ABSTRACT FROM AUTHOR]

Background: Human albumin (HA) infusion is potentially effective for the management of hyponatremia in liver cirrhosis, but the current evidence is very limited. Methods: In this retrospective study, 2414 cirrhotic patients who were consecutively admitted to our hospital between January 2010 and June 2014 were included in the Hospitalization outcome cohort, and 339 cirrhotic patients without malignancy who were consecutively admitted to our department between December 2014 and April 2021 were included in the Long-term outcome cohort. The development and improvement of hyponatremia were compared between patients who received HA infusion during hospitalizations and did not. Logistic and Cox regression analyses were performed to evaluate the association of development and improvement of hyponatremia during hospitalizations with the outcomes. Odds ratios (ORs) and hazard ratios (HRs) were calculated. Results: In the two cohorts, HA infusion significantly decreased the incidence of hyponatremia and increased the rate of improvement of hyponatremia in cirrhotic patients during hospitalizations. In the Hospitalization outcome cohort, the development of hyponatremia during hospitalizations was significantly associated with increased in-hospital mortality (OR = 2.493, p < 0.001), and the improvement of hyponatremia during hospitalizations was significantly associated with decreased in-hospital mortality (OR = 0.599, p = 0.014). In the Long-term outcome cohort, the development of hyponatremia during hospitalizations was significantly associated with decreased long-term survival (HR = 0.400, p < 0.001), and the improvement of hyponatremia during hospitalizations was not significantly associated with long-term survival (HR = 1.085, p = 0.813). Conclusions: HA infusion can effectively prevent the development of hyponatremia and improve hyponatremia in cirrhotic patients during hospitalizations, which may influence the patients' outcomes. [ABSTRACT FROM AUTHOR]

Incorporating graphene sheets into the ceramic matrix can induce a fine microstructure with unique interfaces, in which the excellent mechanical and electrical properties of individual sheets are packed and applied in bulk quantities. However, further development of graphene-ceramic composites is hindered by the poor distribution uniformity and structural integrity of 2D sheets as well as high anisotropy. Here, a self-assembly strategy based on electrostatic adsorption is proposed for the homogeneous and nondestructive fabrication of graphene oxide-ZrO 2 hybrids. By SPS, dense composites are obtained with improved flexural strength (1187 ± 21 MPa), fracture toughness (8.10 ± 0.04 MPa⋅m1/2) and a percolation threshold below 1 wt%. The common anisotropy in graphene composites is restricted, showing consistent properties on different surfaces. A high correlation between resistance change and deformation has been confirmed, which can be well described by binomial equation. The sensitive and stable sensing performance makes this composite a promising smart material for in-situ self-monitoring. [ABSTRACT FROM AUTHOR]

Climate change, characterized by global warming, is profoundly affecting the global environment, politics, economy, and social security. Finding the main causes of climate change and determining their quantitative contributions are key points to making climate decisions on responses to climate change. The Tibetan Plateau (TP) is sensitive to global climate change. Taking the 100 km buffer zones of 45 meteorological stations in the eastern TP as research objects, we conducted an experimental study on temperature change and its influencing factors. Using the least squares multivariate statistical analysis method, a model between the annual and seasonal standardized temperature change and its dynamic influencing factors in the past 20 years was established. The results showed that, in the eastern TP, temperature change was affected by different factors in different periods. Vegetation cover and snow cover were the most correlated factors to temperature change. The influence of carbon dioxide, vegetation cover, and water cover was subject to seasonal changes. Urban cover and bare land cover did not pass the t-test. This research not only provides a theoretical basis for the analysis of temperature change over the TP, but also points out the direction for the analysis of temperature change causes in three polar regions. [ABSTRACT FROM AUTHOR]

Titanium dioxide is a mainstream photocatalyst, but it still confronts great obstacles of poor visible light absorption and rapid recombination rate of photogenerated carriers. Herein, we describe the design of a highly active visible-light photocatalytic system of graphited carbon layers anchored V2O5/TiO2 heterojunctions derived from Ti3C2 MXene, which demonstrates about 4.58 and 2.79 times higher degradation activity of MB under visible light (λ > 420 nm) than pure V2O5 and TiO2-carbon. Combined with the characterization results, the formed V2O5/TiO2 heterojunction promotes the separation of photogenerated carriers, while the graphitized carbon derived from MXene acts as an electronic reservoir to enhance the absorption of visible light. The ESR results show that superoxide radicals and hydroxyl radicals are the main active species in the reaction system. Therefore, we propose a possible mechanism model to provide a feasible idea for the subsequent design of high-efficiency photocatalysts for environmental treatment. [ABSTRACT FROM AUTHOR]

The Jinshajiang–Ailaoshan–Song Ma orogenic belt (JASB), as a vital segment of the eastern Paleo-Tethyan tectonic zone, is one of the most important zones in which to study the Paleo-Tethyan tectonic evolution. We have undertaken an integrated geochronological, petrological, and geochemical study of mafic rocks from the JASB to reveal the subduction and closure processes of the eastern Paleo-Tethyan Ocean during the Permian to Triassic. In conjunction with previous magmatic and metamorphic records in the JASB, three important tectonic stages are identified: (1) Early Permian to Early Triassic (ca. 288–248 Ma). Most of the Early Permian to Early Triassic mafic rocks have normal mid-ocean ridge basalt (N-MORB)- or enriched MORB (E-MORB)-like rare earth elements (REE) and trace element-normalized patterns with positive εNd(t) and εHf(t) values and negative Nb and Ta anomalies. Their La/Nb ratios and εNd(t) values show that approximately 3%–15% of slab-derived fluid accounts for the generation of these rocks. These characteristics suggest that the mafic rocks formed in an arc/back-arc basin setting at this stage. Additionally, the Early Permian mafic rocks are mainly exposed in the Jomda–Weixi–Yaxuanqiao–Truong Son magmatic rock belt (JYTB) on the western side of the JASB, indicating that the westward subduction of the Jinshajiang–Ailaoshan–Song Ma Paleo-Tethys Ocean (JASO) began in the Early Permian. Middle Permian mafic rocks are exposed in the Ailaoshan-Day Nui Con Voi metamorphic complex belt and the JYTB on both sides of the JASB. We propose that the bipolar subduction of the JASO occurred in the Middle Permian and ended in the Early Triassic. (2) Middle Triassic (ca. 248–237 Ma). The mafic rocks at this stage have LREE- and LILE-enriched patterns, negative Nb and Ta anomalies and negative εNd(t) values. Their variable εHf(t), εNd(t) values and La/Nb ratios show that these mafic rocks were highly affected by crustal material (ca. 16%). Considering the Middle Triassic high-pressure (HP) metamorphism and massive Al-enriched felsic magmatism in the JASB, these rocks may have formed in a collisional setting between the South China Block (SCB) and the North Qiangtang–Simao–Indochina Block (QSIB) during the Middle Triassic. (3) Late Triassic (ca. 235–202 Ma). The mafic rocks at this stage have negative εNd(t) and εHf(t) values and show terrestrial array characteristics. The εNd(t) values and La/Nb ratios show that approximately 30% of crustal components account for the generation of these rocks. Combined with the contemporaneous bimodal magma and metamorphism during the Late Triassic, we suggest that these rocks may have formed in a postcollisional extensional setting associated with magma diapir. [ABSTRACT FROM AUTHOR]

The 2D MXene material provides an opportunity for manufacturing ceramic composites with special structures and functions. However, the maintenance of a complete layered structure and controlled exfoliation of few-layered MXene sheets as well as homogeneous distribution should be carefully designed and carried out. Herein, we try to explore some essential questions in the system, including the evolution of phase and morphology of MXene as well as its influence on the microstructure, which is critical. We established a general self-assembly strategy for fabricating MXene-ZrO 2 hybrids by electrostatic interaction. After SPS, fine toughening and conductive network has been constructed in composites with improved mechanical properties and a percolation threshold as low as 1−2 wt.%. The conductivity related to spatial distribution of MXene sheets endows the composite with self-monitoring ability to sense stain and internal cracks in situ. Such composite may be a promising smart material for potential structural and functional applications. [ABSTRACT FROM AUTHOR]

Mixed-flow pump is an important machine for transporting fluids, which has the advantages of both centrifugal pump and axial flow pump, but it is prone to cavitation, endangering efficiency and safe operation. A 20 m × 8.5 m high-precision hydraulic mechanical stand and a vertical mixed-flow pumping station device were built for the study of cavitation signals. The detection of pressure pulsation signal is a direct measurement of the cavitation region, and the decay of information is less. In this study, the time domain and frequency domain characteristics of water pressure pulsation signal are analyzed by using fast Fourier transform method. The power spectrum density (PSD) is used to extract the characteristics of each cavitation stage, especially the full cavitation stage with random signal characteristics. The results show that PSD method reflects more information and is more sensitive than traditional time–frequency domain analysis. The characteristic power spectrum (PS) value of the cavitation of the mixed-flow pump machinery can be given through the feature extraction of the PS, which plays a great role in the effective identification and prevention of cavitation. [ABSTRACT FROM AUTHOR]

• An on-line combustion optimization framework for coal-fired boiler is proposed. • The boiler dynamic combustion model with self-adaptive capability is constructed. • Domain maximum substitution strategy is introduced into the decomposition-based multiple target evolutionary algorithm (D/MOEA) to enhance the optimization power of D/MOEA. • Mutation strategy-based case-based reasoning (MS-CBR) is proposed to gain the combustion optimization adjustment strategy online. • The thermal efficiency could be increased by 0.588 %, and NOx emission could be reduced 14.183 mg/m3, and the difference in operating load reached 0.696 MW. It is important to gain the on-line combustion adjustment strategy under ensuring the running working condition of boiler unchanged. Because it can not only significantly improve the whole combustion environment of boiler, but can ensure the stability and safety of boiler in optimization. This article proposes a kind of new-style on-line combustion optimization framework for boiler combustion system, and this study is to quickly acquire the combustion adjustment strategies to improve the whole combustion environment of boiler under ensuring the operating working condition of boiler unchanged. First, improved culture algorithm based on improved particle swarm optimization and double mutation evolution strategy (CIPSODM) and long-short term memory neural network (LSTM) are combined to establish the boiler dynamic combustion model with self-adaptive capability. The improvement of CIPSODM involves two aspects: introducing clustering analysis to the population space of culture algorithm and adding the double mutation thought to the belief space of culture algorithm. And then domain maximum substitution strategy (DMS) is introduced into the decomposition-based multiple-objective evolutionary algorithm (DMS- D/MOEA) to obtain a great deal of combustion optimization cases offline, and an optimization cases base is established by gathering all optimization cases. Whereafter, mutation strategy is added to the case-based reasoning (MSCBR) to online obtain the combustion optimization adjustment strategy with the same running working condition as the current running working condition of the boiler for stable and safety combustion. Meanwhile, to illustrate the availability of the combination of CIPSODM-LSTM, DMS-D/ MOEA and MSCBR, several different on-line optimization approaches are adopted to acquire the combustion adjustment strategies online for comparison. The experiment results illustrated that the thermal efficiency could be increased by 0.588 % and NOx emission could be reduced 14.183 mg/m3 using proposed online combustion optimization approaches. Furthermore, the difference in operating load between adjustment strategy and current boiler reached the minimum value 0.696 MW in all optimization results. Consequently, proposed the on-line combustion optimization framework can gain the on-line combustion adjustment strategies to maximize thermal efficiency and decrease NOx emission so as to improve the whole running environment of boiler. [ABSTRACT FROM AUTHOR]

Fractures play an important role in controlling the hydraulic conductivity of rock masses, and the aperture significantly influences the magnitude of fracture seepage. In this study, field measurements and experiments were conducted at a well-exposed granite fracture site in the Beishan area, China. Several types of single natural fractures were selected to remove the weathered surface and expose the fresh fractures. Subsequently, measuring ruler dispersion-tangent middle axis (MRD-TMA) method was developed to measure the fracture aperture and capture fracture geometry. Then, electrical resistivity tomography (ERT) technique was employed to investigate the seepage properties of these fractures. The results reveal that MRD-TMA method achieved good flexibility and accuracy in the current measurement of fracture aperture, and ERT is a useful tool for detecting the seepage properties of fractures in hard rock masses. Combined with field observations, the filling form of fractures can be categorized according to the ERT inversion results, as follows: open-weak filling, open filling, loose filling, and fully cemented-closed form, whose seepage properties decrease as the filling density increases. Generally, the open-weak filling is the main water channel in a fracture network, while the fully cemented-closed type is a water-blocking fracture and typically exhibits a pseudo-fracture with a large surface opening. In summary, the method for obtaining the morphological characteristics of the aperture can provide a low-cost and time-efficient approach for fracture logging in the field, and ERT technique provides a reference for the detection of potential hazards caused by connected water-conducting fractures in rock engineering. [ABSTRACT FROM AUTHOR]

• The "light-scattering enhanced effect" of grain boundaries can improve luminescence brightness of YLuAG:Ce phosphor ceramic. • The Lu3+ doping in YAG:Ce not only makes Ce3+ emission blue-shifting to 519 nm, but also improves the thermal stability. • Under an excitation of high-power blue light of 175 W, the intense green emission with LE up to 148.88 lm/W is achieved. Intense green emission is extremely significant to the color rendering index (CRI) of white LEDs. Various green-emitting YLuAG:Ce phosphor ceramics were successfully prepared by vacuum sintering. The effects of Lu3+ doping on structure and luminescence property were investigated in detail. In comparison with YAG:Ce, YLuAG:Ce ceramics own smaller grain size, better luminescence performance and higher thermal stability. The photoluminescence (PL) intensity of YLuAG:Ce ceramics increases by 23.6 % due to the "light scattering enhanced effect". Furthermore, the Ce3+ emission is obviously blue-shifting from 533 nm to 519 nm, and the intensity of YLuAG:Ce ceramics reduces only about 8.9 % at 250 °C, showing better thermal stability (vs 11.1 % of YAG:Ce). The LE of LED packaged by YLuAG:Ce ceramic is up to 148.88 lm/W when the doping Lu3+ y is 2.1. The above results show that tailored YLuAG:Ce phosphor ceramic is a potential green-emitting color converter for high-power LEDs (hp-LEDs). [ABSTRACT FROM AUTHOR]

This study is aimed at better understanding the deformation and failure mechanism of surrounding rock during excavation unloading of a high-stress rock mass and determining the reasonable reinforcement time for the surrounding rock. To fulfill this aim, true triaxial tests were carried out on different loading and unloading paths during the unilateral unloading of a high-stress rock mass. The variational condition for minimization of plastic complementary energy is obtained, the optimal reinforcement time is determined, and the range of the plastic zone in the surrounding rock reinforced by anchor mesh-cable-grouting is compared and analyzed. The results are as follows: (1) Based on the Mohr-Coulomb yield criterion and the deformation reinforcement theory of surrounding rock, the stable state with the minimum reinforcement force is obtained. (2) After the true triaxial tests on the unilateral unloading of the third principal stress were carried out under different confining pressures, loading continued to be performed. Compared with rock failure without confining pressure, in the conventional uniaxial compression test, the failure of samples is dominated by composite splitting-shear failure; the unilateral unloading stress-concentration failure is a progressive failure process of splitting into plates followed by cutting into blocks and then the ejection of blocks and pieces. (3) The relationship between the time steps of the surrounding rock stability and the excavation distance is obtained. The supporting time can be divided into four stages: presupport stage, bolt reinforcement stage, anchor cable reinforcement stage, and grouting reinforcement stage. (4) In the range of within 5 m behind the tunneling face, the plastic zone of the surrounding rock with support is reduced by 7 m as compared with that with no support. In the range of over 5 m behind the tunneling face, the plastic zone of the roadway floor with support is reduced by 2.6 m as compared with that without support, and the deformation is reduced by 90%. These results can serve as a reference for controlling the behavior of surrounding rock during excavation unloading of high-stress rock masses. [ABSTRACT FROM AUTHOR]

The study aimed to analyze the application of diffusion tensor imaging (DTI) in the surgery of benign and malignant intracranial tumors through improved fuzzy C-means (FCM). First, a method of combining the maximum and minimum distances was proposed to improve the FCM algorithm. Then, the optimized FCM was applied to the diffusion tensor imaging (DTI) diagnosis. The patients were rolled into the benign tumor group and the malignant tumor group, and relevant parameters were compared. Finally, the postoperative total resection rate and disability rate of the DTI experimental group and the traditional control (Ctrl) group were evaluated. It was found that the segmentation accuracy of the optimized FCM algorithm was higher than traditional one and the obtained corpus callosum edge contour was clearer. In 63 patients with intracranial space, there were obvious differences in pairwise comparison of meningioma and glioma, metastatic tumor's apparent diffusion coefficient (ADC) value, relative apparent diffusion coefficient (r ADC) value, and relative anisotropy fraction (r FA) P < 0.05 . In terms of the ADC, r ADC, and r FA values of tumor parenchymal area, those of benign tumors were larger than malignant tumors P < 0.05 . The ADC value (8.21 ± 1.87) and r FA value (1.36 ± 0.41) of the contralateral normal white matter area of malignant tumor were greater than the ADC value (7.23 ± 2.31) and r FA value (0.61 ± 0.24) of the peritumor white matter area, with statistically significant differences P < 0.05 . The total cut rates of the experimental group and the Ctrl were 87.5% and 54.84%, and the disability rates were 6.25% and 34.38%. In conclusion, the optimized FCM has high accuracy. The ADC, r ADC, and r FA values of DTI are important in the diagnosis of intracranial tumors. Besides, DTI can improve the survival rate in guiding intracranial tumor resection. [ABSTRACT FROM AUTHOR]

The stability of nonlinear stochastic differential equations driven by time-changed Lévy process with impulsive effects is discussed in this paper. Some sufficient conditions are provided to guarantee the solutions to be stable in different senses. The stochastic perturbation is also investigated for some unstable time-changed differential equations with impulses. The efficiency of the proposed results is illustrated by some examples with numerical simulations. [ABSTRACT FROM AUTHOR]

HDFS is a popular open-source system for scalable and reliable file management, which is designed as a general-purpose solution for distributed file storage. While it works well for medium or large files, it will suffer heavy performance degradations in case of lots of small files. To overcome this drawback, we propose here a system to enhance HDFS with a distributed true full-text search system SAES of 100% recall and precision ratios. By indexing the meta data of each file, e.g., name, size, date and description, files can be quickly accessed by efficient searches over metadata. Moreover, by merging many small files into a large file to be stored with better space and I/O efficiencies, the negative performance impacts caused by directly storing each small file individually are avoided. An experimental study is conducted for function and performance tests on both realistic and artificial data. The experimental results show that the system works well for file operations such as uploading, downloading and deleting. Moreover, the RAM consumption for managing massive small files is dramatically reduced, which is critical for good system performance. The proposed system could be a potential storage solution for massive small files. [ABSTRACT FROM AUTHOR]

An innovative system of graphitic C3N4 with NiCoP as two‐component heterostructured hybrids (NiCoP/g‐C3N4) with efficiently photocatalytic performances for hydrogen production is demonstrated and a simple, morphologically controlled catalyst with an extremely low phosphide load was developed. The hydrogengenerate rate is 1067.11 μmol g−1 h−1 using 1 ωt% NiCoP/g‐C3N4. The incorporation of monodisperse NiCoP nanoparticles into g‐C3N4 effectively optimizes the electronic structures of the hybrids, enhances the corresponding interaction and the activity of hydrogen catalytic site, Moreover,NiCoP/g‐C3N4 Heterostructured Hybrids displayed the favorable stability during the photocatalytic. [ABSTRACT FROM AUTHOR]

Densified SiC ceramics were prepared by using gel-casting method combined with liquid-phase sintering (LPS). In this study, a low-toxicity gel-casting system based on 2-hydroxyethyl methacrylate (HEMA) and N, N′-methylene acrylamide (MBAM) as monomer and crosslinker respectively, was first applied to SiC fabrication. The effects of the processing parameters on gel-casting were investigated in detail to achieve optimized rheological behavior and green body strength. The best result was obtained in the slurry with solid content of 50 vol%, dispersant of 0.4 wt% and monomer/crosslinker ratio of 20 at pH10. With the modified ternary sintering aids (Al 2 O 3 –Y 2 O 3 –CeO 2) added, the densification can be realized at low temperature. After pressureless sintering at 1850 °C for 2 h, the sample with best mechanical properties was obtained. The highest relative density, hardness, flexural strength and fracture toughness were 96.23%, 24.94 GPa, 423.95 MPa and 4.78 MPa/m1/2, respectively. Present work provides an environmentally friendly and energy-saving process for preparing SiC ceramics with excellent properties. [ABSTRACT FROM AUTHOR]

Die Nanotechnologie funktioneller Nukleinsäuren (FNAs) ist ein interdisziplinäres Gebiet, das sich auf die Untersuchung der Wechselwirkungen zwischen FNAs und Nanomaterialien konzentriert und die speziellen Vorteile und Anwendungen von FNA‐Nanomaterialien erforscht. Mit dem Ziel, Biomaterialen der nächsten Generation aufzubauen, die die Vorteile von FNAs und Nanomaterialien kombinieren, haben sich die Wechselwirkungen zwischen FNAs und Nanomaterialien sowie Technologien zur Selbstorganisation von FNAs als wichtige Forschungsgebiete etabliert. Es besteht die Aussicht, dass Targeterkennung, Responsivität und Selbstorganisationsfähigkeit in Kombination mit plasmonischen Eigenschaften, Stabilität, Stimuliresponsivität und Transportfähigkeit verschiedener Nanomaterialien eine Vielzahl an neuartigen faszinierenden Anwendungen erschließen können. Die Forschungen an den strukturellen und funktionellen Eigenschaften von FNAs schreiten rasch voran, und viele Laboratorien haben über zahlreiche Methoden zur Herstellung von FNA‐Nanomaterialien berichtet. In diesem Aufsatz stellen wir zunächst einige weit verbreitete FNAs und Nanomaterialien vor, einschließlich ihrer Klassifizierung, Struktur und Anwendungen, und erläutern die erfolgreichsten Methoden zur Herstellung hochentwickelter FNA‐Nanomaterialien. Des Weiteren diskutieren wir die umfangreichen Anwendungen von FNA‐Nanomaterialien in den Bereichen Bioimaging, Biosensorik und Biomedizin und erläutern unsere Sichtweise der verbliebenen Herausforderungen und Entwicklungstrends. [ABSTRACT FROM AUTHOR]

Functional nucleic acid (FNA) nanotechnology is an interdisciplinary field between nucleic acid biochemistry and nanotechnology that focuses on the study of interactions between FNAs and nanomaterials and explores the particular advantages and applications of FNA nanomaterials. With the goal of building the next‐generation biomaterials that combine the advantages of FNAs and nanomaterials, the interactions between FNAs and nanomaterials as well as FNA self‐assembly technologies have established themselves as hot research areas, where the target recognition, response, and self‐assembly ability, combined with the plasmon properties, stability, stimuli‐response, and delivery potential of various nanomaterials can give rise to a variety of novel fascinating applications. As research on the structural and functional group features of FNAs and nanomaterials rapidly develops, many laboratories have reported numerous methods to construct FNA nanomaterials. In this Review, we first introduce some widely used FNAs and nanomaterials along with their classification, structure, and application features. Then we discuss the most successful methods employing FNAs and nanomaterials as elements for creating advanced FNA nanomaterials. Finally, we review the extensive applications of FNA nanomaterials in bioimaging, biosensing, biomedicine, and other important fields, with their own advantages and drawbacks, and provide our perspective about the issues and developing trends in FNA nanotechnology. [ABSTRACT FROM AUTHOR]

A photocatalyzed intramolecular cyclization is developed for the synthesis of fluorenones. In this photoredox reaction, triphenylphosphine is used as an inexpensive and effective deoxygenative reagent for biarylcarboxylic acids to give acyl radicals, which quickly undergo intramolecular radical cyclization. Reactions in the presence of air and continuous flow photoredox technology demonstrate the generality and practicality of this process. [ABSTRACT FROM AUTHOR]

The direct catalytic dehydrogenation of propane (C3H8) to value‐added propylene (C3H6) has attracted much attention. However, direct dehydrogenation of C3H8 to C3H6 with outstanding catalytic performance at low temperature is a great challenge. Herein, we report a new approach for the direct dehydrogenation of C3H8 to C3H6 at low temperature by microwave catalysis over non‐precious Co−Sn/NC microwave catalyst. It is found that the microwave direct catalytic dehydrogenation of C3H8 over Co−Sn/NC microwave catalyst at low temperature (450 °C) is highly efficient. The C3H8 conversion is 15 % and the C3H6 selectivity is 75 % at 450 °C. Comparatively, the C3H8 conversion and C3H6 selectivity were respectively only 3.2 % and 67.8 % for Co−Sn/NC catalyst at 450 °C in the conventional reaction mode under identical conditions. Furthermore, the microwave catalyst does not show visible change after tested for 180 min. Importantly, the apparent activation energy of Co−Sn/NC catalyst drop from 59.58 kJ/mol in the conventional reaction mode to 20.98 kJ/mol in microwave catalytic reaction mode, which suggests a significant microwave direct catalytic effect. This work provides a novel approach for highly effective direct dehydrogenation of C3H8 to C3H6 by microwave irradiation at low temperature. [ABSTRACT FROM AUTHOR]

To take into account the economy, environment protection and operating safety of the boiler in the combustion optimization process, a new on-line combustion optimization approach for boiler is proposed. The historical combustion data collected from DCS of the coal-fired power plant is preprocessed at first. Then improved biogeography optimization-based long short-term memory neural network (IBBO-LSTM) and similarity measurement method are designed to construct the adaptive dynamic combustion model for boiler with boiler efficiency, NOx emission and the temperature of water wall as outputs respectively. After that improved non-dominated sorting genetic algorithm-Ⅱ (INSGA-Ⅱ) is designed to generate a series of boiler combustion optimization solutions under different running load offline, and improved multi-level fuzzy comprehensive evaluation (IDHGF) is designed to retain the combustion optimization solutions with higher running safety. Meanwhile, the retained optimization solutions are integrated into an optimization cases base. Thereafter, case-based reasoning based on safety enhancement mechanism (CBRSEM) is designed to achieve the online combustion optimization for boiler. Finally, to confirm the effectiveness of the combination of IBBO-LSTM, INSGA-Ⅱ, IDHGF and CBRSEM, different online optimization methods (IBBO-LSTM-INSGA-Ⅱ, IBBO-LSTM-INSGA-Ⅱ-IDHGF, IBBO-LSTM-NSGA-Ⅱ-DHGF-CBR, IBBO-LSTM-NSGA-Ⅱ-IDHGF-CBR, IBBO-LSTM-NSGA-Ⅱ-DHGF-CBRSEM, IBBO-LSTM-NSGA-Ⅱ-IDHGF-CBRSEM, IBBO-LSTM-INSGA-Ⅱ-DHGF-CBR, IBBO-LSTM-INSGA-Ⅱ-IDHGF-CBR) are adopted to optimize a given combustion case. The proposed on-line combustion optimization approach for boiler received satisfied combustion optimization results that the growing for boiler efficiency was 0.653%, and the reduced concentration for NOx emission reached 22.891 mg/m3, and the operating safety raised from 5.592 to 6.913. In conclusion, IBBO-LSTM-INSGA-Ⅱ-IDHGF-CBRSEM can online offer the combustion optimization strategy to the boiler operators to improve boiler efficiency, reduce NOx emission and enhance the running safety of boiler, so that it is suitable for online application. • A new online combustion optimization method for boiler is proposed by combining multi-objective optimization algorithm and performance evaluation theory. • Improved biogeography optimization-based long short-term memory neural network are used to construct the self-adaptive dynamic mathematical mode for boiler combustion system. • Improved non-dominated sorting genetic algorithm-Ⅱand improved multi-level fuzzy comprehensive evaluation are combined to gain a series of combustion optimizations with higher boiler efficiency, lower NOx emission and higher operating safety offline. • Case-based reasoning based on safety enhancement mechanism is used to realize the online combustion optimization of boiler. • The boiler efficiency increased by 0.653%, and the NOx emission reduced by 22.891 mg/m3, and the operating safety raised from 5.592 to 6.913. [ABSTRACT FROM AUTHOR]

Herein, we report the first protocol for visible-light-induced radical isocyanide insertion reactions between 3-(2-isocyanobenzyl)-indoles and bromodifluoroacetates or bromodifluoroacetamides. The protocol, which has good functional group tolerance and a broad substrate scope, constitutes an efficient and general route to difluoromethylated spiro[indole-3,3′-quinoline] derivatives. [ABSTRACT FROM AUTHOR]

The development of dinuclear transition metal catalysis has gained considerable momentum in recent years. The synergistic interaction between two metals enables the development of dinuclear metal catalysts with high efficiency, robustness and uniqueness. In this highlight, we take the transition metals Ni and Pd as examples, and provide a current perspective of synthetic methodology development catalyzed by dinuclear Ni- and Pd-complexes in the past several years. The new catalytic reactivities of dinuclear Ni- and Pd-complexes are discussed. [ABSTRACT FROM AUTHOR]

An atomistically-informed constitutive model based on multiplicative hyper-elasto-plasticity with damage is developed for the study of high-pressure induced densification of silica glass. At the atomistic level, a molecular dynamics (MD) representative volume element of amorphous silica (a-SiO2) is first constructed using the melt-quench approach. Within the MD framework, the deformation response of the RVE at different pressure and strain-rate levels is investigated. Results from the volumetric compression simulations suggest occurrence of irreversible densification at pressure above ~ 8 GPa whereas coupled compression-shear tests show yielding behavior of a-SiO2 upon sufficiently large shear deformation. In addition, rate dependency of densification/yielding behavior has been observed. Based on the data obtained from the MD simulations, a novel continuum-based multiplicative hyper-elasto-plasticity-damage model that accounts for the anomalous densification behavior is developed and then parameterized using both polynomial regression and deep learning techniques. The elasto-plasticity model alone captures densification behavior of "perfect" amorphous silica but does not account for damage evolution attributed to "imperfections". To impart the dynamic damage evolution, a plasticity-damage variable that controls the shrinkage of the yield surface is introduced and integrated into the elasto-plasticity model in a manner similar to the JH-2 model. The resulting coupled elasto-plasticity-damage model is reformulated to a non-ordinary state-based peridynamics model for computational efficiency of impact simulations. We show that the as-developed peridynamics model is capable of reproducing coarse-scale quantities of interest found in MD simulations and yet being able to simulate at a component level. Finally, the proposed atomistically-informed multiplicative hyper-elasto-plasticity-damage model has been validated against limited available experimental results for simulation of hyper-velocity impact simulation of projectiles on silica glass targets. [ABSTRACT FROM AUTHOR]

We report on high dielectric constant (8.3 × 103, 104 Hz), low dielectric loss (0.029, 104 Hz) as well as fine grain size (∼840 nm) achieved in pure CaCu 3 Ti 4 O 12 (CCTO) ceramics through a combination of sol–gel method, spark plasma sintering and annealing process. By adjusting the sintering temperature and annealing conditions, the composition variations, valence states and microstructures of CCTO ceramics are systematically studied, which provide direct clues in understanding the origin of their excellent dielectric response. Through the studies on the dielectric, impedance, modulus and conductivity properties of CCTO ceramics, a modified brick-layer model based on two interfacial polarizations originating from sub-grain boundary and grain boundary barriers is proposed to explain their dielectric behaviors. The high dielectric constant of CCTO ceramics is mainly dominated by the sub-grain contribution; and the reduced dielectric loss is attributed to the decreases of electrical conductivity and relaxation loss. [ABSTRACT FROM AUTHOR]

This review (with 126 references) summarizes the progress that has been made in the use of carbon nanotubes (CNTs) in immunoassays and immunosensors. Following an introduction into the field, a first large section covers functional group-modified CNTs as carriers for antibodies (with subsections on CNTs modified with amino, carboxy and by various other materials). The next section treats CNTs coupled with inorganic or organic materials as active components (with the use of nanoparticles such as Fe3O4, ZnO, gold) or with indium tin oxide (ITO), NiCoBP, ionic liquids, TiO2 nanosheets, metal clusters; chitosan, polystyrene, polydopamine, graphene, or enzymes. Another section discusses the synergistic effects of CNTs with metals, metal ions, and organic/inorganic materials. Several Tables are presented that give an overview on the wealth of methods and materials. A concluding section summarizes the current status, addresses current challenges, and gives an outlook on potential future trends. [ABSTRACT FROM AUTHOR]

This study focuses on the problem of constraint consensus of discrete‐time multi‐agent systems with high‐order heterogeneity. It is assumed that the agents are of different orders in such systems ranging from order 1 to l and the velocity of each agent is constrained to lie in a non‐convex set. This study proposes a distributed constraint control algorithm which guarantees the agents converge to a common point through the use of local information. Model transformations of the system matrix are performed in this study, so that the authors can utilise the properties of the stochastic matrix. Meanwhile, the boundness of state‐dependent stochastic matrices and the convexity of stochastic matrices are analysed and explored in detail. Finally, a numerical example is given to illustrate the correctness of the results. [ABSTRACT FROM AUTHOR]

In this work, Ag nanoparticle loading Mg(C10H16O4)2(H2O)2(Ag@MOF) composite material was successfully prepared by a facile strategy, and subsequently Ag-MOFs were used to modify the PVDF ultrafiltration membranes to obtain fouling resistance and higher water flux. The as-prepared PVDF membranes were systematically characterized by a series of analytical techniques such as Water Contact Angle (CA), Scanning Electron Microscopy (SEM), and SEM-mapping. Furthermore, the performance of membranes on antibacterial properties, the pure water flux, and fouling resistance was investigated in detail. Those results showed that the membrane modified by Ag@MOFs containing 30% Ag had the higher anti-bacterial performance, and the clear zone could be increased to 10 mm in comparison with that of blank membrane. Meanwhile, the pure water flux of Ag@MOF membranes increased from 85 L/m2 h to 157 L/m2 h, and the maximum membrane flux recovery rate (FRR) of 95.7% was obtained using SA as pollutant, which is attributed to the introduction of Ag@MOF composite material. Based on the above experimental results, it can be found that the Ag-MOF membranes displayed the excellent antibacterial activity, high water flux, and fine fouling resistance. This work provides a facile strategy to fabricate the Ag@MOFs modified membranes, and it shows an excellent anti-bacterial and water flux performance. [ABSTRACT FROM AUTHOR]

Herein, we describe a protocol for alkylation reactions of C(sp3)–H bonds with diacyl peroxides by means of a process involving cross-coupling between an alkyl radical and an α-aminoalkyl radical. The mild, catalyst- and additive-free conditions make this protocol superior to previously reported C(sp3)–H alkylation strategies. The protocol was applied to 1,2,3,4-tetrahydroisoquinolines and a tetrahydro-β-carboline derivative and could be carried out on a gram scale, indicating its utility for the alkylation of late-stage synthetic intermediates. [ABSTRACT FROM AUTHOR]

This review (with 147 references) summarizes the state of the art in methods for signal amplification in immunoassays by using noble metal nanoparticles (MeNPs). Following an introduction into the field, a first large section covers MeNPs as signal tracers. The next sections describes the use of MeNPs as carriers for biomolecules, and of doped, decorated or functionalized MeNPs. A next large section covers MeNPs as used in aggregation-based assays that result in a change of color or dynamic light scattering (DLS). This is followed by a discussion of MeNPs that undergo etching, size reduction, or growth and thereby change color and DLS, with subsections on methods based on etching, particle growth or particle formation. We then rview methods where MeNPs acts as catalysts (enzyme mimics), with subsections on MeNPs and on doped or composed MeNPs. A final large section discusses the synergies of MeNPs or multiple signal amplification strategies in immunoassays. Several Tables are presented that give an overview on the wealth of methods and materials. A concluding section summarizes the current status, addresses current challenges, and gives an outlook on potential future trends. [ABSTRACT FROM AUTHOR]

The direct decomposition of H 2 S into CO x -free H 2 and S is an attractive approach in respect of both environmental and energy advantages. However, to achieve the highly effective direct H 2 S decomposition reaction is a critical scientific challenge, owning to the serious thermal equilibrium limitation in this reaction. Herein, we develop carbon encapsulated Mo 2 C–Co 2 C/SiC composite (Mo 2 C–Co 2 C/SiC@C) via in-situ microwave carbonization, as a novel microwave catalyst for highly effective direct decomposition of H 2 S into CO x -free H 2 and S by microwave catalysis. Significantly, the H 2 S conversion is impressively up to 90.3% at 750 °C over Mo 2 C–Co 2 C/SiC@C microwave catalyst in the microwave catalytic reaction mode, which greatly surpasses the corresponding H 2 S equilibrium conversion in the conventional reaction mode. Importantly, Mo 2 C–Co 2 C/SiC@C exhibits outstanding stability under microwave irradiation. It is found that microwave catalysis can break the chemical equilibrium limitation of the H 2 S decomposition reaction, which displays a significant microwave selective catalytic effect. This work provides a novel route for high value utilization of toxic and abundant H 2 S resources, and thus opens a new approach for the design of high active and stable microwave catalysts in microwave catalytic reactions. Image 1 • H 2 S conversion is highly up to 90.3% at 750 °C under microwave irradiation. • Mo 2 C–Co 2 C/SiC@C successfully prepared via a novel in-situ microwave carbonization. • Mo 2 C–Co 2 C/SiC@C is high active and stable for H 2 S decomposition in the MCRM. • Catalytic activity in the MCRM is much higher than that in the CRM. • Microwave irradiation can break chemical equilibrium of H 2 S decomposition reaction. [ABSTRACT FROM AUTHOR]

In the field of aerospace and advanced equipment manufacturing, accurate response analysis has been paid more attention, requiring a more comprehensive study of the variation of mechanical parameters with the service environment. The damping variation characteristics of 304 aluminum alloy, Sa564 high-strength alloy, GW63K magnesium alloy, and Q235 steel were investigated in this paper, which plays a significant role in the dynamic responses of structures. Variable damping ratios were revealed by the damping tests based on a dynamic mechanical analysis (DMA). The numerical method of temperature/frequency-dependent damping parameters in stochastic dynamics was focused on. With a large variation in the damping ratio, a numerical constitutive relation for temperature-dependent damping was proposed, and an efficient stochastic dynamics method was derived to analyze the responses of structures based on the pseudo excitation method (PEM) and variable damping theory. The computational accuracy and validity of the proposed method are confirmed during the vibration tests and numerical analysis. Based on the comparison results of the two damping models and the experiments on GW63K alloy, we proved that the proposed method is more accurate to the real response of the actual engineering structure. The differences in dynamic responses between the constant damping and experiments are significant, and more attention should be paid to the numerical method of stochastic dynamic response of variable damping materials in the aviation and aerospace fields and high-temperature environments. [ABSTRACT FROM AUTHOR]

The structure and composition of a Co/Re trilayer and a 19-period superlattice were characterized by high-resolution transmission electron microscopy (TEM) and scanning TEM (STEM). Low-angle x-ray reflectivity measurements were performed and compared with the TEM results. The Re and Co layers are epitaxial with their (1010) planes parallel to the (1120) plane of Al2O3, and the [001] direction of Re and Co layers coincides with that of the Al2O3. The in-plane lattice parameters for Co, Re, and Al2O3 are approximately 0.24 and 0.43 nm, 0.26 and 0.44 nm, and 0.24 and 0.44 nm, respectively, in the superlattice. The lattice spacing of Al2O3 corresponds to a/2 and c/3, where a and c are lattice parameters of the Al2O3. High-angle and low-angle annular-dark-field STEM and nanoscale electron energy loss spectroscopy line analysis exhibit very weak interdiffusion between Co and Re layers; therefore, very sharp interfaces are maintained in the superlattice. The initial interface roughness between the Re buffer layer and the first Co layer is amplified during the subsequent growth of the superlattices. Layer thickness fluctuations are much smaller in the Re/Co superlattice than the interface roughness, which suggests that interface roughness plays a more important role in the giant magnetoresistance effect than thickness fluctuations of the spacer layer. [ABSTRACT FROM AUTHOR]

Carbon nitride (CNx) thin films were prepared by radio-frequency magnetron sputtering combined with a nitrogen radical beam source. X-ray photoelectron spectroscopy, Raman spectroscopy, and grazing-incidence x-ray reflectivity have been used to analyze the chemical composition and structure of the CNx films. An atomic force microscope equipped with a diamond tip was employed to measure the hardness of the films. The nitrogen concentration, composition, hardness, density, and surface roughness varied with the operating power and gas flow applied to the sputtering target and radical gun in the sample preparation. CNx films were fabricated with a maximum nitrogen concentration of ∼62 at. % on the surface and ∼44 at. % after Ar[sup +] sputtering, as well as a maximum hardness of ∼33.7 GPa. Compared with N[sub 2][sup +] and N[sub 2], excited molecular and atomic nitrogen were more active in the formation of carbon nitrides. With the combination of magnetron sputtering, the radical beam source enables an obvious increase in the nitrogen concentration but only a slight increase in the film hardness. A relationship between the Raman spectra and hardness was found: CNx films with a higher G peak frequency and lower I[sub D]/I[sub G] have higher hardness. Our results also suggested that a higher concentration of the sp[sup 3] phase produces a harder CNx film. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Focuses on a study on the structure and growth morphology of antimony (Sb) mediated carbon (C...) films, prepared by predepositing a layer of surfactant Sb over mica, silicon and glass substrates with the vacuum vapor deposition method. Possible growth mechanisms of the Sb mediated C... films; Experimental procedure; Results and discussion; Conclusions.

ZrC-SiC nanocomposites were synthesized via a facile, green hydrothermal precursor conversion method. The zirconium, silicon and decomposed glucose can be successfully incorporated into a homogeneous framework. In subsequent pyrolysis, the precursor transforms to a core-matrix structure of the nano-ZrO 2 and amorphous carbon/silica mixture, resulting in a short diffusion path and limited grain growth. Carbide first appears at a low temperature of 1200 °C, and the conversion is completed at 1500 °C with low oxygen content. The composite consists of grains about 100 nm, exhibiting specific embedded morphology, and has different oxidation resistance in three temperature zones based on the component. The origin mechanism and properties have been elucidated and analyzed. The present work demonstrates the effectiveness of hydrothermal chemistry for the synthesis of carbide composites and their promising application in high temperature protection. Such nanocomposites with controllable morphology and high sinterability beneficial for subsequent densification are also verified. The additive-free ceramic has been obtained with almost fully density (relative density >99%) at a low temperature of 1700 °C by spark plasma sintering (SPS). The sintered specimen possesses fine microstructure with hierarchical grain size distribution (about 1 μm and 100 nm, respectively) and good mechanical properties (fracture toughness of 4.3 ± 0.4 MPa m1/2 and Vickers hardness of 22.8 ± 0.7 GPa). Image 1 • ZrC-SiC nanocomposites were prepared from hydrothermal precursor at low temperature for the first time. • The origin of embedded morphology and reaction mechanism for composites was investigated. • The improved oxidation resistance with temperature-dependency has been elaborated. • Fully dense ceramic was achieved without additive at a low temperature of 1700 °C. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Magnetic separable NiCo 2 O 4 -Bi 2 O 2 CO 3 composite was found to be excellent MW catalyst. • High 4-NP and TOC removal ratios achieved without adding extra oxidants. • NiCo 2 O 4 -Bi 2 O 2 CO 3 show excellent stability with removal ratios of 97.31% in 5 cycles. • OH generated under MW irradiation acts as primary oxidant in the MCOD process. • MCOD over NiCo 2 O 4 -Bi 2 O 2 CO 3 open a new promising avenue for degradation of pollutants. Abstract A novel magnetically separable NiCo 2 O 4 -Bi 2 O 2 CO 3 composite was developed as an effective microwave catalyst for microwave catalytic oxidation degradation of 4-nitrophenol without adding any oxidant. X-ray photoelectron spectroscopy (XPS) and Roman spectroscopy confirmed that the surface of the NiCo 2 O 4 in NiCo 2 O 4 -Bi 2 O 2 CO 3 composite had a composition containing Co2+, Co3+, Ni2+, and Ni3+. The results show that the NiCo 2 O 4 -Bi 2 O 2 CO 3 microwave catalyst exhibited impressively high catalytic activity with 4-nitrophenol removal ratio of 94.70% in only 1 min and 97.27% within 7 min in this attractive microwave catalytic oxidation degradation approach without adding any oxidant. Moreover, the TOC removal ration can reach up to 93.33%. Importantly, NiCo 2 O 4 -Bi 2 O 2 CO 3 catalyst displays excellent stability with the degradation efficiency as high as 97.31% even after five rounds of degradation process. The impressively high catalytic activity for the degradation of 4-nitrophenol could be ascribed to the production of OH under microwave irradiation. This work builds a new approach for highly effective degradation of wastewater, and provides some guidelines for design of microwave catalysts for microwave catalytic oxidation degradation process. [ABSTRACT FROM AUTHOR]

Abstract An electrochemical biosensor based on Cu2+-dependent cleavage DNAzyme (cDNAzyme), Exponential Amplification Reaction (EXPAR), and single-strand triggered DNA hybridization chain reaction (HCR) was developed for detecting the copper (II) ions. This method capitalizes on the specific recognition of cDNAzyme, the single strand accumulated isothermal amplification of EXPAR, and the enzyme-free isothermal DNA assembly of HCR. In the presence of Cu2+, the catalytic chain of cDNAzyme split the substrate chain to produce single-stranded DNA (Oligo X). With the help of the EXPAR, the trace Oligo X was amplified and converted to the initiator DNA (Oligo Y). After adding the initiator DNA (Oligo Y) into nanochannel, massive DNA superstructures grew from the capture probe (CP) that were pre-immobilized on the nanochannel wall, resulting in a sharp decrease of the effective diameter of the nanochannel. As a result, the transmembrane ionic current significantly decreased due to the effective closing of the nanochannel. Finally, the copper (II) ion was detected by monitoring the changes of transmembrane ionic current. The developed electrochemical biosensor also displayed high selectivity for Cu2+, which could be useful for monitoring Cu2+ above ten picomole. Highlights • An artificial gate-like biosensor for ultrasensitive detection of heavy metal ion. • The metal-specific cleaving DNAzyme was used to guarantee the specificity of sensor. • Exponential Amplification Reaction (EXPAR) was used to amplify the signal. • A DNA-responsive nanochannel was fabricate using the HCR powered DNA assembly. • Cyclic utilization of the sensor was achieved using two invasion DNAs. [ABSTRACT FROM AUTHOR]

Abstract: The first transition‐metal‐free, site‐specific umpolung trifluoromethylthiolation of tertiary alkyl ethers has been developed, achieving the challenging tertiary C(sp3)–SCF3 coupling under redox‐neutral conditions. The synergism of organophotocatalyst 4CzIPN and BINOL‐based phosphorothiols can site‐selectively cleave tertiary sp3 C(sp3)–O ether bonds in complex molecules initiated by a polarity‐matching hydrogen‐atom‐transfer (HAT) event. The incorporation of several competing benzylic and methine C(sp3)−H bonds in alkyl ethers has little influence on the regioselectivity. Selective difluoromethylthiolation of C−O bonds has also been achieved. This represents not only an important step forward in trifluoromethylthiolation but also a promising means for site‐selective C−O bond functionalization of unsymmetrical tertiary alkyl ethers. [ABSTRACT FROM AUTHOR]