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Proper interface and band alignment always play essential roles in the separation of photoexcited charge of photocatalysts. In this work, we prepared a homodispersed S-scheme carbon nitride homojunction with local electron structure difference by a facile pre-doping and two-step calcination approach. Boron doping into heptazine created extra acceptor impurity, and Phosphorus doping into heptazine created extra donor impurity, which eventually modulated the electronic structure of carbon nitride. As heptazines with different element doping were integrated into carbon nitride by recalcination, B-CN and P-CN formed a homodispersed homojunction and thus produced a rich interface. Meanwhile, caused by Fermi energy levels equilibrium, the band bending constructed an S-scheme homojunction, which stimulated photogenerated electrons to transfer from CB of B-CN to VB of P-CN. The homodispersed S-scheme homojunction structure led to efficient suppression of recombination of photoinduced charge and retained stronger redox charge. Consequently, the photocatalytic performance was dramatically boosted to 2620 μmol g-1 from 60 μmol g-1 of pure CN in four-hour hydrogen evolution from water. This novel method for electron structure engineering helped to provide a new strategy for designing homojunction photocatalysts with excellent photocatalytic performance.

This study aims to establish a novel method for measuring perospirone in human plasma for therapeutic drug monitoring (TDM) by liquid chromatography-mass spectrometry (LC-MS) coupled with an automatic liquid chromatograph mass spectrometer coupler 9500 (LC-MS/MS-Mate 9500), which has been equipped with self-internal standard (SIS) calibration technology.A novel and attractive analytical calibration method designed for perospirone, calibration with SIS, was reported. After protein precipitation with acetonitrile-cyclopentanol (9:1, v/v) containing 1% NHThis method showed good selectivity because no interfering peaks were observed in the plasma samples during the 2.0-min run time. The calibration curve range was 0.05-20 ng/mL, with a correlation coefficient of ≥ 0.9995. Intraday and interday accuracies were 98.3%-107.9%, respectively, with precision relative standard deviation values of 10%. The matrix effects ranged from 92.7% to 96.1%, and extraction recoveries were between 97.3% and 108.8%. Finally, this method was successfully applied to routine clinical TDM for 142 patients. The perospirone plasma concentrations of the patients ranged between 0.07 and 10.96 ng/mL.This bioanalytical method can be used for the quantification of perospirone in human plasma by LC-MS/MS-Mate 9500 using perospirone itself as the SIS.

Venous thromboembolism (VTE) is a common health problem, causing considerable morbidity and mortality. The incidence of VTE is higher in pregnant women than in those who are not pregnant. However, genetic factors for VTE in pregnant women are largely unknown.We performed a large-scale prospective cohort study of 65,138 pregnancies. 24 pregnant patients diagnosed with VTE and 24 matched pregnant women without VTE were enrolled and sequenced by whole exome sequencing. We investigated the occurrence of known VTE risk variants, damaging variants found in thrombophilia genes and rare damaging variants possibly related to VTE in pregnancies. An exome-wide association study was also performed using a case-control design.Our findings suggest that VTE in pregnancies may be mainly related to (i) the presence of known pathogenic variants in affected individual like F2, (ii) possibly damaging variants found in major thrombophilia gene GCKR, and (iii) 1 pathogenic and 13 likely pathogenic rare damaging variants associated with genetic errors. In exome-wide association stage, 42 variants at 34 genes may show suggestive associations with VTE in pregnancies (the lowest P = 3.5 × 10The combined findings suggest that some genes may be involved in the mechanism of basement membranes, sterol accumulation and atherosclerosis, lipid metabolism and coagulation deficiency. These identified risk variants may improve the understanding of VTE pathogenesis in pregnancies and provide potential biomarker for development of clinical diagnosis.

Safe and efficient hydrogen storage technology is of great significance for large-scale hydrogen energy utilization. Using metal hydride (MH) materials such as LaNi5 for hydrogen storage is an effective way. In application, the heat and mass transfer characteristics in the reactor are one of the important factors and key problems affecting the hydrogen storage performance of MH. This paper proposes a novel hydrogen storage reactor installing a concentric finned tube heat exchanger and using phase change materials (PCM) by surrounding the reactor to improve heat transfer and hydrogen storage performance. A numerical model is built to describe transportation and reaction of two reactors with or without PCM. By comparison, the reactor surrounded by PCM has faster heat discharge and hydrogen absorption rate, and the absorption time is shortened by 50%. For the reactor with PCM, the optimal amount of PCM and the inlet velocity of heat transfer fluid (HTF) are investigated. The results show that the effective thermal conductivity of MH play a key role to improve heat transfer and reaction rate rather than that of PCM. Furthermore, increasing hydrogen supply pressure can effectively accelerate heat discharge and hydrogen absorption rate owning to larger temperature differences and improved reaction kinetics.

The construction of defects in semiconductor photocatalysts, as a kind of modification methods, plays an indispensable role in the enhancement of the photocatalytic performance. Herein, nitrogen defects were successfully introduced into the framework of graphite carbon nitride (CN-Tx) through thermal polymerization with melamine and 1,2,4-triazole as precursors. The existence of nitrogen defects in CN-Tx were confirmed to be located at the two-coordinated (N2c) C N–C lattice sites, which resulted in the destruction of its planar structure and the initiation of n-π∗ electron transition that greatly expanded the response range to visible light and improved the separation efficiency of photogenerated charge carrier. More significantly, CN-Tx could enhance photocatalytic water purification activity towards different kinds of pollutants. The photocatalytic rates of CN-T3 were estimated to be 2.54 (tetracycline) and 2.31 (2-hydroxynaphthalene) times higher than those of pristine g-C3N4. Furthermore, the possible photocatalytic degradation mechanism over CN-Tx photocatalyst was proposed by free radical trapping experiments combined with ERS characterization. This work provides an in-depth understanding of the important role of nitrogen defects in the electronic structure and chemical properties of g-C3N4 and its photocatalytic water purification performance.

Graphene (Gr) is a monolayer of carbon atoms in a two-dimensional honeycomb lattice, and has derivatives of graphene oxide and reduced graphene oxide. Gr is widely used in various fields for its good optics, conductivity, mechanical properties, low toxicity, antibacterial properties, biocompatibility and stability. Graphene oxide and reduced graphene oxide have similar properties to Gr, and all three materials have advantages and disadvantages and are often not used alone but are composited with other materials to improve their properties for a particular application. From the perspectives of the toxicity and antibacterial properties of Gr and its derivatives, this paper reviews their uses in treating skin wounds and tumours, promoting the regeneration of skeletal muscle and bone, and facilitating drug loading and diagnosis. The problems associated with these applications are analyzed and solutions are suggested. Future research and development prospects for Gr-based materials are presented.

Porous g-C3N4 nanosheets (PCN) were prepared by the nickel-assisted one-step thermal polymerization method. Hydrogen (H2) which was produced by the reaction between nickel (Ni) foam and ammonia (NH3) defined the structure and properties of PCN. During the formation of PCN, the participation of H2 not only enhanced the spacing between layers but also boosted the specific surface area that more active sites were exposed. Additionally, H2 promoted pores formation in the nanosheets, which was beneficial to the transfer of photons through lamellar structure and improved the absorption efficiency of visible light. Remarkably, the obtained PCN possessed better Cr(VI) photocatalytic reduction efficiency than pure g-C3N4. The reaction rate constant (k) of PCN (0.013 min−1) was approximately twice that of bare g-C3N4 (0.007 min−1). Furthermore, the effects of original pH and concentration of Cr(VI)-containing solution on removal efficiency of Cr(VI) were explored. A possible photocatalytic mechanism was proposed based on the experiments of radical scavengers and photoelectrochemical characterizations.

To better understand the characteristics and transformation mechanisms of secondary inorganic aerosols, hourly mass concentrations of water-soluble inorganic ions (WSIIs) in PM2.5 and their gaseous precursors were measured online from 2016 to 2018 at an urban site in Beijing. Seasonal and diurnal variations in water-soluble ions and gaseous precursors were discussed and their gas-particle conversion and partitioning were also examined, some related parameters were characterized. The (TNH3) Rich was also defined to describe the variations of the excess NH3 in different seasons. In addition, a sensitivity test was carried out by using ISORROPIA II to outline the driving factors of gas-particle partitioning. In Beijing, the relative contribution of nitrate to PM2.5 has increased markedly in recent years, especially under polluted conditions. In the four seasons, only a small portion of NO2 in the atmosphere was converted into total nitrate (TNO3), and more than 80% of TNO3 occurred in the form of nitrate due to the abundant ammonia. The concentration of total ammonia (TNH3) was much higher than that required to neutralize acid gases, and most of the TNH3 occurred as gaseous NH3. The nitrous acid (HONO) concentration was highly correlated with NH3 concentration and had increased significantly in Beijing compared with previous studies. The total chloride (TCl) was the highest in winter, and e(Cl−) was more sensitive to variations in the ambient temperature (T) and relative humidity (RH) than e(NO3−).

An analytical protocol was developed to quantify six-category pharmaceuticals in surface water under paralleling pHs using a combination of solid phase extraction (SPE) and high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). Of 121 compound standards commercially, 94 compounds were reliably quantified using a paralleling pH combination at 3 and 9 with a sound recovery-rate of 50-150%. The quantified compounds covered 6 categories as 37 antibiotics, 16 central nervous system drugs (CNs), 14 cardiovascular drugs (CVs), 12 endocrine and family planning drugs (EFs), 8 antiparasitic drugs (APs), and 7 non-steroidal anti-inflammatory drugs (NSAIDs). The protocol achieved limits of detection and quantitation in ranges of 0.001–11.9 ng L–1 and 0.003–39.7 ng L–1, respectively. Serial field surface water samples from Jiulong River in Fujian, China were testified using the protocol with 41 quantified compounds of the above-mentioned 6 categories from < LODs to 1,389 ng L−1 (caffeine). The key procedure prior to the SPE is to split filtrate of each surface water sample into two portions, adjusted to pH 3 and 9 separately and both spiked with 0.2 g Na2EDTA.

NaCl–CaCl2 molten salt is considered as a promising high-temperature heat transfer and storage fluid for advanced nuclear power plants and concentrating solar power plants in the field of renewable energy utilization. However, the comprehensive physical properties and their microscopic mechanisms for the molten NaCl–CaCl2 are failed to be measured accurately due to the extremely measuring condition. In this work, the ab-initio molecular dynamics simulation is used to investigate its microstructures and thermophysical properties for entire operating temperatures. It reveals that ion clusters are formed in terms of three for face-sharing, two for edge-sharing, and one for corner-sharing Cl− ions between the coordination shells of two neighboring cations. The coordination numbers of Na+-Cl- and Ca2+-Cl- ion pairs decrease from 5.88 to 6.46 at 783 K to 5.33 and 6.02 at 1173 K respectively. Meanwhile, the reliable and meaningful values of densities, ion self-diffusion coefficients, viscosities, and thermal conductivities were evaluated from 783 to 1173 K. It suggests that the distances and interactions between ions pairs determine thermodynamic properties directly. The ab-initio molecular dynamics simulation is proved to be an effective way to obtain the essential data for the designs of heat transfer and thermal energy storage systems in practical applications.

In view of the critical role of autophagy-related genes (ARGs) in the pathogenesis of various diseases including cancer, this study aims to identify and evaluate the potential value of ARGs in head and neck squamous cell carcinoma (HNSCC).RNA sequencing and clinical data in The Cancer Genome Atlas (TCGA) were analyzed by univariate Cox regression analysis and Lasso Cox regression analysis model established a novel 13- autophagy related prognostic genes, which were used to build a prognostic risk model. A multivariate Cox proportional regression model and the survival analysis were used to evaluate the prognostic risk model. Moreover, the efficiency of prognostic risk model was tested by receiver operating characteristic (ROC) curve analysis based on data from TCGA database and Gene Expression Omnibus (GEO). Besides, the other independent datasets from Human Protein Atlas dataset (HPA) also applied.13 ARGs (GABARAPL1, ITGA3, USP10, ST13, MAPK9, PRKN, FADD, IKBKB, ITPR1, TP73, MAP2K7, CDKN2A, and EEF2K) with prognostic value were identified in HNSCC patients. Subsequently, a prognostic risk model was established based on 13 ARGs, and significantly stratified HNSCC patients into high- and low-risk groups in terms of overall survival (OS) (HR = 0.379，95% CI: 0.289-0.495, p 0.0001). The multivariate Cox analysis revealed that this model was an independent prognostic factor (HR = 1.506, 95% CI = 1.330-1.706, P 0.001). The areas under the ROC curves (AUC) were significant for both the TCGA and GEO, with AUC of 0.685 and 0.928 respectively. Functional annotation revealed that model significantly enriched in many critical pathways correlated with tumorigenesis, including the p53 pathway, IL2 STAT5 signaling, TGF beta signaling, PI3K Ak mTOR signaling by gene set variation analysis (GSVA) and gene set enrichment analysis (GSEA). In addition, we developed a nomogram shown some clinical net could be used as a reference for clinical decision-making.Collectively, we developed and validated a novel robust 13-gene signatures for HNSCC prognosis prediction. The 13 ARGs could serve as an independent and reliable prognostic biomarkers and therapeutic targets for the HNSCC patients.

This study investigates overconfident traders who underestimate their contemporaries’ information processing ability, and it examines the impact of these traders on the financial market within the framework of social networks. As a byproduct, we also explore the impact of traders who overestimate their own ability, which is another manifestation of overconfidence. We find that when information acquisition is endogenous, market outcomes are improved by the effects of both underestimation and overestimation biases. The underlying logic is that traders’ overconfidence adds friction to free-riding on contemporaries’ information, thereby mitigating the information crowding-out effect of social communication. The results are robust to the extension of endogenous network formation and varying information acquisition costs.

Cross-linked enzyme aggregates (CLEAs) are considered as an effective tool for the immobilization of enzyme. The ionic cross-linking agent-sodium tripolyphosphate (TPP) was first used in preparing CLEAs. Aspergillus niger lipase was precipitated with ammonium sulfate and further cross-linked by TPP. The factors including enzyme concentration, pH of cross-linking medium, TPP dosage and cross-linking time were optimized. Maximum recovery activity (99.5 ± 0.634 %) and cross-linking yield (88.4 ± 0.46 %) can be obtained under the optimal process conditions, which can illustrate TPP had little effect on enzyme activity. CLEAs showed improved activity over broad pH and temperature range compared to the free enzyme. The thermal stability was obviously improved compared to free enzyme under the optimal temperature (40℃) and the half-life was 7.5-fold higher than that of free enzyme. Moreover, scanning electron microscopy (SEM) revealed that CLEAs had a cavity with porous structure and the particle size was 249 ± 3.98 nm. X-ray diffraction (XRD) showed the crystallinity of the CLEAs decreased. The changes in secondary structures of CLEAs revealed the increment in conformational rigidity. Such results suggested that the CLEAs has ideal application prospects.

In this work, a series of solar salt nano-fluids with 2.5 wt%, 3.5 wt%, 4.5 wt%, 5.0 wt% and 10.0 wt% MgO nanoparticles (∼60 nm, 18 W/m·K[24]) have been prepared and their thermal properties over 220 °C have been studied. The viscosity (η), density (ρ), specific heat capacity (cp) and thermal diffusivity (α) of the nano-fluids have been measured by rotary viscometer, Archimedean technique, differential scanning calorimeter (DSC) and laser flash analysis (LFA) respectively. The thermal conductivity (λ) is determined by ρ, cp and α. The results show that the viscosity and density of nano-fluids are about 5.1 cp∼2.4 cp and 1.96 g/cm3∼1.83 g/cm3 at 240 °C–380 °C which is close to that of solar salt fluid. The average cp of the fluids with nano-MgO from zero to 5.0 wt% is 1.442–1.613 J/(g·K), and the λ of fluids is 0.37–0.60 W/(m·K) at 375 °C. The enhancement of cp and λ of nano-fluids reaches 11.9% and 62.1%, which increases the Nusselt number with improved heat transfer performance. It is suggested that the nano-fluid with 5.0 wt% MgO in solar salt is a promising fluid for application of heat transfer and thermal storage in a CSP system.