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Graphitic carbon nitride (g-C3N4) has been extensively investigated over the past decade for its potential utilizations in photocatalytic energy generation and pollutant degradation. To better meeting the requirements for practical utilizations, it is crucial to address the issue of poor charge separation properties in g-C3N4, which origin from the strong interactions in photogenerated electron-hole pairs. In this review, we summarized the pertinent studies on developing strategies to promote the charge separation properties of g-C3N4. The strategies can be categorized into two categories of promoting the surface migration of charge carriers and prolonging the lifetime of surface charge. Finally, we present potential challenges in promoting charge separation and offer feasible suggestions to face these challenges.

In order to address the issues of excessive brittle intermetallic compounds (IMC) formation in the TC4 brazed joints, two types of novel Ti-Zr-Cu-Ni-Sn amorphous braze fillers were designed. The microstructure and shear strength of the TC4/Ti-Zr-Ni-Cu-Sn/TC4 brazed joints were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffractometer (XRD) and electronic universal materials testing machine. The results show that the optimized Ti35Zr25Ni15Cu20Sn5 braze filler whose chemical composition is closer to the eutectic point possesses a lower melting point compared with the equiatomic Ti23.75Zr23.75Ni23.75Cu23.75Sn5. This was beneficial to the sufficient diffusion of Cu and Ni elements with the base metal during brazing and reduces the residual (Ti,Zr)2(Ni,Cu) content in the joint, which helps to improve the joint performance. The room-temperature and high-temperature shear strength of the TC4 brazed joints using the near eutectic component Ti35Zr25Ni15Cu20Sn5 filler reached a maximum of 472 MPa and 389 MPa at 970 °C/10 min, which was 66% and 48% higher than that of the TC4 joints brazed with the equiatomic Ti23.75Zr23.75Ni23.75Cu23.75Sn5 braze filler. Microstructural evolution and the corresponding mechanical response were in-depth discussed.

Abstract Neutral bits and boomerangs are key techniques for accelerating collision search in SHA‐1 attacks. The current acceleration techniques for SHA‐1 near‐collision attacks are reviewed and a generic search framework for neutral bits and boomerangs is presented. The framework can efficiently construct auxiliary paths for a given differential path and message bit relations and find and store ideal boomerangs. The framework was applied to free‐start attacks for 76‐step SHA‐1, and the complexity was reduced from 250.25 ${2}^{50.25}$ to 247.9 ${2}^{47.9}$. Relaxing the boomerang's restrictions on message words, the authors propose an accelerating technique termed semi‐boomerangs, combined with the search framework of boomerangs, which increases the speed of collision search by 3.48 times in a free‐start attack for 80‐step SHA‐1 and the complexity for 80‐step attack was reduced from 257.5 ${2}^{57.5}$ to 255.7 ${2}^{55.7}$.

Herein, a novel concept was proposed to address the issue that continuous brittle phases degrade the mechanical properties of a brazed joint. In this concept, the continuous brittle phases could become dispersive by inserting a network-like structure to divide the brazing seam spatially. This concept was verified in a specific brazing system, where Ti3SiC2 ceramic and Ti2AlNb alloy were brazed by an AgCu interlayer. Ductile Cu foam with a network-like structure was used to disperse the continuous brittle TiCuSi intermetallic that should have in-situ formed in the Ti3SiC2/AgCu/Ti2AlNb brazed joint. Results show that the effect of Cu foam on dispersing the brittle TiCuSi intermetallic is pronounced. The effects of holding time and pore size on the dispersion effect of Cu foam were investigated. The joint fracture analysis and micro-mechanical properties of phases analysis reveal that the dispersive TiCuSi intermetallic is superior to the continuous one. The reason is that the microstructure of discrete TiCuSi intermetallic surrounded by ductile Ag-based and Cu-based solid solutions has a more robust capacity to accommodate microcracks. Thus the brazed joint is toughened and strengthened.

Thermal stabilizers, lubricant, and plasticizers are three crucial additives for processing poly(vinyl chloride) (PVC). In this study, a new mannitol stearate ester-based aluminum alkoxide (MSE-Al) was designed and synthesized as a novel additive for PVC. The thermal stability and processing performance of PVC stabilized by MSE-Al were evaluated by the Congo red test, conductivity measurement, thermal aging test, ultravioletevisible (UV−Vis) spectroscopy test, and torque rheometer test. Results showed that the addition of MSE-Al could not only markedly improve the long-term thermal stability of PVC, but also greatly accelerate the plasticizing and decrease the balance torque, which demonstrated that MSE-Al possessed a lubricating property. Thus, MSE-Al was demonstrated to be able to provide tri-functional additive roles, e.g., thermal stabilizer, plasticizer, and lubricant. The test results for the thermal stability of PVC indicated that the initial whiteness of PVC stabilized by MSE-Al was not good enough, thus the synergistic effect of MSE-Al with zinc stearates (ZnSt2) on the thermal stability of PVC was also investigated. The results showed that there is an appreciable synergistic effect between MSE-Al and ZnSt2. The thermal stabilization mechanism and synergism effect of MSE-Al with ZnSt2 are then discussed.

A new di-mannitol adipate ester-based zinc metal alkoxide (DMAE-Zn) was synthesized as a bi-functional poly(vinyl chloride) (PVC) thermal stabilizer for the first time. The materials were characterized with Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). Characterization results confirmed the formation of Zn−O bonds in DMAE-Zn, and confirmed that DMAE-Zn had a high decomposition temperature and a low melting point. The thermal stability of DMAE-Zn on PVC also was tested by a conductivity test, a thermal aging test, and a UV-visible spectroscopy (UV-VIS) test. PVC stabilized by DMAE-Zn had a good initial color and excellent long-term stability. UV-VIS also showed that the conjugated structure in PVC stabilized by DMAE-Zn was almost all of the triene, suggesting that the addition of DMAE-Zn would suppress the formation of conjugated structures above tetraene. The dynamic processing performance of PVC samples tested by torque rheometer indicated that, having a good compatibility with PVC chains in the amorphous regions, DMAE-Zn contributed a good plasticizing effect to PVC. DMAE-Zn thus effectively demonstrates bi-functional roles, e.g., thermal stabilizers and plasticizers to PVC. Furthermore, FT-IR, a HCl absorption capacity test, and a complex ZnCl2 test were also used to verify the thermal stability mechanism of DMAE-Zn for PVC.

Copper nanorods were synthesized using controlled-current electrochemical methods. The surfactants in the electrolyte served as both a templates and stabilizers during the synthesis procedure. TEM images show that the products consist mainly of nanosized rod-like structures. The current density applied during the electrodeposition was found to have an effect on the shape and yield of the copper nanorods.

A sandwich-type electrochemical immunosensor was designed for quantitative detection of prostate specific antigen (PSA). Gold-platinum bimetallic functionalized tin oxide graphene (GS-SnO2-Au@Pt) has a large specific surface area, good conductivity and biocompatibility, which was used as the sensing interface to capture PSA coating antibody (Ab1). The copper ions doped Ag-Au nanospheres (Cu2+@Ag-Au) was prepared and used as a label of PSA labeling antibody (Ab2), which generated high intensive electrochemical redox signal based on the reduction reaction of Cu2+. The L-cysteine was applied as a bridge to connect Au nanoparticles (NPs) and Ag NPs, and to keep the nanosized gap between Au nuclear and Ag shell. This structure not only makes full advantage of space effect to load more Ag NPs but also increases the specific surface area for loaded more Cu2+. The proposed immunosensor with a wide range (10 pg mL−1 to 100 ng mL−1) and a low detection limit (3.84 pg mL−1) shows excellent performance in the detection of PSA. The results indicate that proposed immunosensor provides a promising application for the quantitative detection of biomolecules in serum samples. [ABSTRACT FROM AUTHOR]

Atherosclerosis is a leading cause of cardiovascular disease, and atherosclerotic cardiovascular disease accounts for one-third of global deaths. However, the mechanism of atherosclerosis is not fully understood. It is well-known that the Rho GTPase family, especially Rho A, plays a vital role in the development and progression of arteriosclerosis. Rho guanine nucleotide exchange factors (Rho GEFs), which act upstream of Rho GTPases, are also involved in the atheromatous pathological process. Despite some research on the role of Rho GEFS in the regulation of atherosclerosis, the number of studies is small relative to studies on the essential function of Rho GEFs. Some studies have preliminarily revealed Rho GEF regulation of atherosclerosis by experiments in vivo and in vitro. Herein, we review the advances in research on the relationship and interaction between Rho GEFs and atheroma to provide a potential reference for further study of atherosclerosis.

Atherosclerosis preferentially occurs in atheroprone vasculature where human umbilical vein endothelial cells are exposed to disturbed flow. Disturbed flow is associated with vascular inflammation and focal distribution. Recent studies have revealed the involvement of epigenetic regulation in atherosclerosis progression. N6-methyladenosine (m6A) is the most prevalent internal modification of eukaryotic mRNA, but its function in endothelial atherogenic progression remains unclear. Here, we show that m6A mediates the epidermal growth factor receptor (EGFR) signaling pathway during EC activation to regulate the atherosclerotic process. Oscillatory stress (OS) reduced the expression of methyltransferase like 3 (METTL3), the primary m6A methyltransferase. Through m6A sequencing and functional studies, we determined that m6A mediates the mRNA decay of the vascular pathophysiology gene EGFR which leads to EC dysfunction. m6A modification of the EGFR 3’ untranslated regions (3’UTR) accelerated its mRNA degradation. Double mutation of the EGFR 3’UTR abolished METTL3-induced luciferase activity. Adenovirus-mediated METTL3 overexpression significantly reduced EGFR activation and endothelial dysfunction in the presence of OS. Furthermore, thrombospondin-1 (TSP-1), an EGFR ligand, was specifically expressed in atheroprone regions without being affected by METTL3. Inhibition of the TSP-1/EGFR axis by using shRNA and AG1478 significantly ameliorated atherogenesis. Overall, our study revealed that METTL3 alleviates endothelial atherogenic progression through m6A-dependent stabilization of EGFR mRNA, highlighting the important role of RNA transcriptomics in atherosclerosis regulation.

Fe-Mn-Al-C lightweight steels have been investigated intensely in the last a few years. There are basically four types of Fe-Mn-Al-C steels, ferritic, ferrite-based duplex/triplex (ferrite + austenite, ferrite + austenite + martensite), austenite-based duplex (ferrite + austenite), and single-austenitic. Among these steels, austenite-based lightweight steels generally exhibit high strength, good ductility, and outstanding weight reduction effects. Due to the addition of Al and high C content, κ’-carbide and κ-carbide are prone to form in the austenite grain interior and at grain boundaries of lightweight steels, respectively, and play critical roles in controlling the microstructures and mechanical properties of the steels. The microstructural evolution, strengthening mechanisms, and deformation behaviors of these lightweight steels are quite different from those of the mild conventional steels and TRIP/TWIP steels due to their high stacking fault energies. The relationship between the microstructures and mechanical properties has been widely investigated, and several deformation mechanisms have also been proposed for austenite-based lightweight steels. In this paper, the current research works are reviewed and the prospectives of the austenite-based Fe-Mn-Al-C lightweight steels are discussed.

Calcific aortic valve disease (CAVD), a common heart valve disease, is increasingly prevalent worldwide and causes high morbidity and mortality. Here, we aimed to investigate a possible role for miR-34c in the development of osteogenic differentiation during CAVD and to find out the underlying mechanisms. Valvular interstitial cells (VICs) were isolated from the clinical aortic valve tissue samples of CAVD patients and patients with acute aortic dissection and collected. Then, RT-qPCR was performed to determine miR-34c expression and western blot analysis was applied to confirm the relevant protein expression in these VICs. Dual luciferase reporter gene assay was applied to confirm the relation between miR-34c and STC1. Alkaline phosphatase (ALP) staining and alizarin red staining was performed to further confirm the degree of calcification in these samples. MiR-34c was lowly expressed and STC1 was highly expressed in the CAVD tissues. Furthermore, STC1 was the target of miR-34c and was negatively regulated by miR-34c. Overexpression of miR-34c in VICs was concomitant with suppression of both STC1 expression and phosphorylation level of c-Jun N-terminal kinase (JNK). In addition, significant decrease of bone morphogenetic protein-2 (BMP2) and osteocalcin, as well as the decrease of calcification degree were also observed in VICs with miR-34c overexpressed. Taken together, miR-34c could inhibit osteogenic differentiation and calcification of VICs by suppressing the STC1/JNK signaling pathway in CAVD, making miR-34c a novel therapeutic target for the treatment of CAVD.

Traditional bridge evaluation techniques are based on design-based deterministic equations that use limited site-specific data. They do not necessarily conform to a quantifiable standard of safety and are often quite conservative. The newly emerging load and resistance factor rating (LRFR) method addresses some of these shortcomings and allows bridge rating in a manner consistent with load and resistance factor design (LRFD) but is not based on site-specific information. This paper presents a probability-based methodology for load-rating bridges by using site-specific in-service structural response data in an LRFR format. The use of a site-specific structural response allows the elimination of a substantial portion of modeling uncertainty in live load characterization (involving dynamic impact and girder distribution), which leads to more accurate bridge ratings. Rating at two different limit states, yield and plastic collapse, is proposed for specified service lives and target reliabilities. We consider a conditional Poisson occurrence of identically distributed and statistically independent (i.i.d.) loads, uncertainties in field measurement, modeling uncertainties, and Bayesian updating of the empirical distribution function to obtain an extreme-value distribution of the time-dependent maximum live load. An illustrative example uses in-service peak-strain data from ambient traffic collected on a high-volume bridge. Serial independence of the collected peak strains and of the counting process, as well as the asymptotic behavior of the extreme peak-strain values, are investigated. A set of in-service load and resistance factor rating (ISLRFR) equations optimized for a suite of bridges is developed. Results from the proposed methodology are compared with ratings derived from more traditional methods. [ABSTRACT FROM AUTHOR]

Non-ferrous metal smelting enterprises produce hundreds of thousands of tons of arsenic sulfide sludge (ASS) each year in China. Most of the ASS are stored at the companies without enough preventive measures. During the storage and natural drying process, arsenic sulfide is easily oxidized, thereby causing secondary pollution and increasing environmental risks. In this paper, experiments of simulated storage were used to study the release characteristics of heavy metals. During the simulated storage, the release concentrations of As, Pb, and Cd increased rapidly at first and then slowly. Although the total amount of arsenic released was the largest, the release ratio was in the order of Cd > Pb > As. The effects of different atmospheres and conditions on the release of arsenic and heavy metals were explored. The more the H2SO4 in the sludge, the higher the release concentration, and the addition of an appropriate amount of Ca(OH)2 is beneficial for reducing the release of heavy metals. Finally, SEM, XRD and TG-DTG techniques were carried out to confirm that the release of heavy metals was caused by the oxidation process resulting from the residual H2SO4 in the ASS and the air.