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This article used a high-temperature and high-pressure Hastelloy reactor to simulate the harsh corrosion environment. The effects of different Cl- concentrations(0, 5 000, 10 000, 15 000 mg/L)on the corrosion mechanism of N80 tubing steel in the extraction fluid was studied. The corrosion rate, corrosion morphology and corrosion film structure of N80 tubing steel was analyzed using a combination of macroscopic and microscopic means. The variability of corrosion in different Cl- content environments was clarified. The results showed that the corrosion rate rose significantly with the elevation of Cl- concentration, and the pits on the surface of the corrosion products gradually increased. The large amount of Cl- enrichment destroyed the originally dense corrosion film, exposing N80 tubing steel to the corrosion solution. The presence of trace O2 made the concentration difference battery occur, accelerating the corrosion process. [ABSTRACT FROM AUTHOR]

• DMSO and MOE were proposed for the first time to improve the surface morphology of the films. • The optimum mixing ratio is V MOE = V DMSO = 2 mL, and the solution to the precursor film is completed in the air environment. • The efficiency of the fabricated CZTSSe solar cell is 10.99% with V oc of 510.6 mV, J sc of 33.19 mA/cm2, and FF of 64.83 %. A mixed dimethyl sulfoxide (DMSO) and 2-methoxy ethanol (MOE) solvent system was developed to prepare high-quality kesterite Cu 2 ZnSn(S, Se) 4 (CZTSSe) film. The precursor films made pure DMSO system show a tube-like microstructure morphology, which can be changed by adding MOE to the solution. The increase of MOE in the precursor solution is a key in the crystalline characteristic of the absorber and connecting performance with thin film solar cells. As V MOE = V DMSO , the CZTSSe layer can achieve good contact with the back electrode and obtain large grains across layers. The addition of MOE solvent effectively improves the fill factor (FF). Specifically, both the fill factor and efficiency are increased from 49.67% and 6.43% to 64.83% and 10.99%, respectively, with the addition of 2 mL of MOE into precursor solution prepared by DMSO. [ABSTRACT FROM AUTHOR]

The effects of silty sand and pH on the corrosion characteristics of 1Cr steel were investigated. The results revealed that silty sand changed the nucleation behaviour of FeCO3 crystal from homogeneous nucleation to heterogeneous nucleation through increasing the critical supersaturation of FeCO3. The compactness and protection of corrosion film were improved by silty sand. The amorphous FeCO3 content decreased as the pH increased in the CO2 environment with silty sand, while the Cr(OH)3 content increased. The critical pH for the good corrosion resistance of 1Cr steel was 4.5. The amorphous FeCO3 dominated the protective properties of corrosion film when the pH was lower than the critical pH, whereas the Cr(OH)3 was predominant when the pH was higher than the critical pH. Therefore, the corrosion resistance of 1Cr steel was reduced and then enhanced with increasing pH under silty sand condition. [ABSTRACT FROM AUTHOR]

Shale oil is an unconventional oil resource that needs to be developed and utilized urgently. However, the Chang 7 shale in the Ordos Basin, as the most typical continental source rock in China, is limited by the study of organic matter (OM) enrichment factors in continental lacustrine facies, and there are still controversies about the controlling factors, which limit the progress of oil and gas exploration. This paper aims to reconstruct the paleoenvironment of Chang 7 shale in the southern margin of Ordos Basin and reveal the controlling factors of organic rich shale by organic and elemental analysis, X-ray diffraction (XRD) analysis, thin section observation, and scanning electron microscopy-energy dispersive spectrometer (SEM-EDS) analysis. The results show that during the deposition period of Chang 7 shale, the climate was warm and humid, the lake water has strong reducing, low salinity and rapid depth changes. Total organic carbon (TOC) is positively correlated with salinity and hydrothermal action and inversely proportional to terrigenous input. The high productivity, low consumption and low dilution result in high enrichment of shale OM in the southern margin of Ordos Basin. [ABSTRACT FROM AUTHOR]

The corrosion behavior of 2205 duplex stainless steel (2205 DSS) was investigated by atomization tests, which was performed in an S-bearing thin electrolyte layer used as the artificial industrial-marine environment. Electrochemical methods and X-ray photoelectron spectroscopy (XPS), were conducted to reveal the protection properties and the composition evolution of the passive film. The results indicated that the corrosion time would weak the protectiveness of passive film, which was attributed to the accumulation of defects and metal sulfides in the passive film. The decrease of composition percentage of Cr2O3 made more negative effects on the protection properties of passive film than the increase of Cr(OH)3 and CrO3, whose formation was related to the adequate supply of oxygen and water molecules. The metal sulfides such as NiS and MoS2 formed during atomization tests reduced the content of alloy oxides in the passive film, and provided locations for the growth of defects. [ABSTRACT FROM AUTHOR]

The leptin receptor ( LEPR ) gene is a member of the class I cytokine receptor family, which plays an important role in weight regulation, fat accumulation and neuroendocrine function in animals. This study aimed to explore the association of single nucleotide polymorphisms (SNPs) of the LEPR gene with growth and carcass traits in meat-type quail by PCR amplification and DNA direct sequencing. In this study, genomic DNA was extracted from blood samples of 36 female Savimalt (SV) quails and 49 female French Giant (FG) quails. Growth traits (measured at 3 or 5 wk) and carcass traits (measured at 5 wk) were used for LEPR gene association analysis. The results showed the existence of 9 SNPs (T81C, G90T, C187A, A191G, A219G, G258A, C286T, G346A, and G373A) of the LEPR gene in the 2 quail strains. The statistical analyses indicated that these SNPs of LEPR gene was significantly associated with shank circumference (SC), shank length (SL), breastbone length (BBL), heart rate (HR), and whole net carcass rate (WNCR) of FG (P < 0.05); chest width (CW), body length (BL), leg muscle rate (LMR), whole net carcass rate (WNCR), and heart rate (HR) of SV (P < 0.05). While haplotypes showed significant effect on SL, BBL, heart weight (HW), WNCR, and HR of FG (P < 0.05). Therefore, the LEPR gene may serve as a molecular genetic marker for improving growth and carcass traits in quails. [ABSTRACT FROM AUTHOR]

The localized corrosion induced by (Ca, Mn)S-(Al, Mg)O complex inclusions was investigated. It revealed that MgO·Al 2 O 3 served as cores and MnS·CaS as shells in the carbon steel. MnS and CaS acted as an anodic phase in the galvanic corrosion formed with steel matrix, while MgO and Al 2 O 3 had no galvanic couple effect with MnS and CaS. MnS was the most preferentially dissolved and triggered localized corrosion, which expanded in the order of CaS-Fe-MgO·Al 2 O 3. The driving force for sulfides and steel matrix dissolution was the effect of galvanic couple, and high local plastic deformation caused by oxides, respectively. • MnS and CaS could form the galvanic corrosion with steel matrix, while MgO and Al 2 O 3 had no galvanic couple effect. • MnS was the most preferentially dissolved as an anodic phase and triggered localized corrosion. • Pit nucleated at the MnS position, and expanded in the order of CaS-Fe-MgO·Al 2 O 3. • Driving force for carbon steel matrix dissolution was the effect of high local plastic deformation caused by MgO·Al 2 O 3. [ABSTRACT FROM AUTHOR]

• The post-heating treatment (PHT) precursor films were adopted to modify the morphology significantly. • The research results indicate that proper PH treatment can modify the surface morphology of precursor films, which is crucial for preparing high-quality absorber layers, the optimum PH temperature was 60 °C. • The best efficiency of the fabricated CZTSSe solar cell is 11.07%, with V oc of 504.6 mV, J sc of 37.69 mA/cm2, and FF of 58.19% In the solution method, the surface morphology characteristic of the precursor film is essential for obtaining the high quality of the absorber layer. Herein, the post-heating treatment (PHT) precursor films were adopted to modify the morphology significantly and the effects of different PHT temperatures on the properties of precursor films, absorber layer films, and photovoltaic devices were investigated. The precursor film with a more porous surface could be obtained by PHT, which facilitates the downward diffusion of Se easily during sulfoselenization and the formation of a large-grain-spanning monolayer structure. Furthermore, the Cu 2 ZnSn(S, Se) 4 absorber layer surface holes were significantly reduced, owing to sufficient grain growth during sulfoselenization. As a result, the device efficiency with PHT was increased to 11.07% mainly due to improved Cu 2 ZnSn(S, Se) 4 absorber spectral response. This study might provide a new potential method for adjusting precursor film morphology and thus enhancing the corresponding device performance. [ABSTRACT FROM AUTHOR]

The effect of silty sand on the pre-passivation behaviour of 1Cr steel in a CO2 aqueous environment was investigated by electrochemical measurements and immersion tests. The results indicated that the cathodic reaction was accelerated by silty sand at the initial corrosion stage, but it was inhibited during the late corrosion stage. The corrosion film presenting as one single layer structure under silty sand condition was mainly composed of Cr(OH)3, amorphous FeCO3, and silty sand. The content of Cr(OH)3 in the film with silty sand was lower and then higher than that without silty sand with increasing corrosion time. The film was separated by silty sand at the early stage and it was filled with silty sand during the late stage. In addition, the pre-passivation behaviour of 1Cr steel under silty sand condition was weakened and then strengthened compared to sand-free condition. [ABSTRACT FROM AUTHOR]

The opposed wall-fired boiler is widely used in Chinese power plants due to its adaptability. However, deviations from design conditions can cause the reduction of combustion efficiency and combustion stability, and the overheating of heating surfaces. This study conducted numerical simulations on a 600 MW supercritical opposed wall-fired boiler at 75%, 50%, and 30% Turbine Heat Acceptance (THA) load conditions. The variation of temperature field and heat flux in the furnace under different loads, and parameters such as distributions of heat flux, temperature, and the stress of the high-temperature heating surface are analyzed. Results indicate that reducing the load from 75% to 30% THA lowers the furnace outlet temperature from 1158 to 1009 K and reduces the average gas temperature of the high-temperature heating surface from 1800 to 1570 K. Under a high load, the maximum heat flux concentrates on the side water-cooled wall of the combustion zone. However, when the load decreases, the heat absorption shifts towards the main combustion zone. Furthermore, under a high load, the average wall temperature of the high-temperature heating surface remains at 1600 K with a uniform temperature distribution. In contrast, when the load drops to 30% THA, significant temperature differences appear on the heating surface, with a maximum difference of 400 K. This leads to excessive expansion and slagging on the high-temperature heating surface, particularly in the middle and lower sections, due to the increased stress. These findings offer valuable insights for optimizing the combustion characteristics of opposed wall-fired boilers and preventing overtemperature explosions on the platen heating surface. [ABSTRACT FROM AUTHOR]

Background/Aims: Vascular calcification and hypertension are intimately linked, and the progression of hypertension is closely correlated with endothelial dysfunction. However, the role of endothelial cells (ECs) in vascular calcification of hypertension remains unclear. Therefore, the present study explored the effects of ECs on calcification of smooth muscle cells (SMCs) from aortas of spontaneously hypertensive rats (SHR). Methods: Aortic ECs and SMCs were isolated from SHR and Wistar rats, respectively. The roles of ECs in the regulation of SMCs calcification were investigated by co-culture and conditioned culture model. Calcium deposition of SMCs was detected by von Kossa staining. Quantization of calcium content in SMCs was determined colorimetrically by the o-cresolphthalein complexone method. Alkaline phosphatase (ALP) activity was measured colorimetrically by p-nitrophenol. The expression levels of MMP-2, MMP-9 and the calcification-promoting proteins were analyzed by Western blot. Results: Calcium deposition, ALP activity and the expression levels of calcification-promoting proteins in SMCs of SHR were significantly higher than that cultured without ECs after 6 days of co-culture with ECs or conditioned culture with the medium of ECs, however, there were no statistical differences between SMCs of Wistar rats. MMP-2 and MMP-9 in co-cultured ECs from SHR were dramatically higher than that cultured without SMCs, nevertheless, there were no statistical differences between ECs from Wistar rats and between SMCs from SHR or Wistar rats. Moreover, SB-3CT, a specific inhibitor of gelatinases, decreased calcium content and the expression levels of calcification-promoting proteins in both co-cultured and conditionally cultured SMCs from SHR. Conclusion: ECs have the ability to promote calcification of aortic SMCs of SHR, and elevated expressions of MMP-2 and MMP-9 in ECs of SHR might facilitate the calcification of SMCs. [ABSTRACT FROM AUTHOR]

Abstract The anisotropic fracture behavior of cold-drawn pearlitic steels was analyzed up to a true strain of 1.6. The structures were analyzed and quantified by scanning electron microscopy, electron backscatter diffraction and high-resolution electron microscopy. The aspect ratio Λ was defined to describe the fracture mechanism based on statistics pertaining to major axis and minor axis of pearlitic colonies, and the fitting formula was established as follows: Λ = 0.4 exp (2 x) + 0.65. At Λ ≤ 2.75, the fracture mechanism shifts from cleavage to quasi-cleavage fracture due to dislocation generation, as the measured parameters of interlamellar spacing (ILS) showed no obvious decrease. At values of Λ > 2.75, ductile fracture mechanism becomes dominant due to a drastic decrease in ILS. The <110> ferrite fiber microtexture formed during the cold drawing process and the component exhibiting a gradient distribution from the surface to the central regions increased gradually with drawing. The crack propagation path was then deflected and formed a ‘V’ shape at ε ≤ 1.5. However , as carbon migrated from cementite to the ferrite near the interphase, the fracture path deflected again. Furthermore, two reasonable models were formulated to explain fracture crack forming and anisotropic fracture behavior. In addition, this study illustrated that the relative crystallographic orientation of the ferrite and cementite components followed the Bagarytski relationship. With increasing strain, the cementite layers transformed from single crystals into nanostructured polycrystals and even evolved an amorphous structure at the interface at strains above 1.5. [ABSTRACT FROM AUTHOR]

The octagonal tangentially fired boiler can be utilized for burning lignite with high moisture. Co-firing biomass in an octagonal tangential boiler is considered a promising approach. A numerical simulation is carried out in this study to analyze the impact of flue gas recirculation (FGR) and the biomass blending ratio on heat and mass transfer in an octagonal tangentially fired boiler. When the FGR rate increases from 0 to 30%, the maximum temperature in the boiler decreases from 2162.8 to 2106.5 K. Simultaneously, the average temperature of the center longitudinal section decreases from 1589.0 to 1531.9 K. The maximum fluctuation of the outlet flue gas temperature remains within 10.9 K for the four calculated working conditions. Consequently, the efficiency of the boiler is basically unchanged. However, the flue gas temperature at the furnace outlet decreases significantly from 1605.9 to 1491.9 K. When the biomass blending ratio increases from 0 to 20%, the mean temperature of the primary combustion zone decreases from 1600.5 to 1571.2 K. [ABSTRACT FROM AUTHOR]

The deformation and fracture behaviors of cementite in pearlitic steels during tensile tests were investigated by in situ scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM) and electron backscatter diffraction (EBSD). The results showed that the deformed structure had three different types of shear bands: shear deformation in the pearlite colonies, at the interfaces of the pearlite colonies and at the phase boundary between ferrite and cementite. The orientations of the shear bands were nearly anisotropic with respect to the tensile axis. The path of shear deformation developed at the dislocation walls and was propagated by the offset of the cementite along the dislocation walls. As the dislocations cut perpendicularly through the cementite layers, the single-crystalline cementite platelets were divided into many nanometer-sized subgrains by the effects of the shearing stress. This process hindered dislocation movement and led to the accumulation of complex dislocations at the adjacent ferrite lamellae. Thus, the plastic deformation of the cementite layers was characterized by bulging until they fractured. The pearlitic texture component was evenly distributed, and the crystallographic axes of the colonies were randomly oriented. Hence, three different shear models characterized the crack propagation process, which occurred in a linear fashion and could be considered the pearlite colonies as a displacement unit for forward expansion. [ABSTRACT FROM AUTHOR]

We investigate a reaction-diffusion-advection equation of the form ut-uxx+βux=f(u)(t>0,0 with mixed boundary condition at x=0 and Stefan free boundary condition at x=h(t). Such a model may be applied to describe the dynamical process of a new or invasive species adopting a combination of random movement and advection upward or downward along the resource gradient, with the free boundary representing the expanding front. The goal of this paper is to understand the effect of advection environment and no flux across the left boundary on the dynamics of this species. For the case |β|, we first derive the spreading-vanishing dichotomy and sharp threshold for spreading and vanishing, and then provide a much sharper estimate for the spreading speed of h(t) and the uniform convergence of u(t, x) when spreading happens. For the case |β|≥c0, some results concerning virtual spreading, vanishing and virtual vanishing are obtained. Here c0 is the minimal speed of traveling waves of the differential equation. [ABSTRACT FROM AUTHOR]

The effect of reversed austenite on the pitting behavior of super 13Cr martensitic stainless steel (S13Cr MSS) was investigated. The results revealed that reversed austenite was a FCC structure with Ni enrichment after tempering process, and there were no Ni-depleted regions adjacent to it. The reversed austenite content increased with increasing tempering temperature, and the pit depth decreased, as well as the dispersion degree of the Kelvin potential distribution. The reversed austenite reduced the risk of pitting corrosion through increasing the passive film compactness, and inhibiting Cl- penetration. Accordingly, the pitting corrosion resistance was enhanced as the tempering temperature increased. • Ni enriched reversed austenite content increased as the tempering temperature increased. • Reversed austenite formation restricted the movement of dislocations and reduced the dislocations density in the S13Cr MSS. • Reversed austenite reduced pitting corrosion through increasing the passive film compactness and inhibiting Cl- penetration. • High reversed austenite content led to the good pitting corrosion resistance for S13Cr MSS. [ABSTRACT FROM AUTHOR]

To develop a high-performance solar refrigeration technology, a novel refrigeration system composed of a perovskite solar cell (PSC) and a thermionic refrigerator (TIR) is constructed. Based on theories of photovoltaic effect, thermionic emission and non-equilibrium thermodynamics, the coefficient of performance (COP) and refrigerating capacity of the integrated system are mathematically expressed, in which the various irreversible losses are taken into consideration. The integration characteristics and coupling relationships between the PSC and TIR are investigated, and the working voltage regions for the combined operation of the subsystems are determined. Furthermore, the impacts of the area ratio, the work function, the environment temperature, the cold reservoir temperature and the heat transfer coefficient on systemic performance are evaluated in detail. Numerical calculation examples illustrate that the maximum COP and maximum refrigerating capacity of the integrated system are 0.81 and 81.2 W, respectively. Analysis results show that there exist optimal area ratio and work function to optimize the system performance. The present study may offer some fresh perspectives on the evolution of the solar refrigeration system. • A PSC-driven TIR refrigeration system is proposed. • Performance indicators for the integrated system are formulated. • The generic performance features of the hybrid system are demonstrated. • The working voltage regions for the coupling system are determined. • The effects of key parameters on the system performance are analyzed. [ABSTRACT FROM AUTHOR]

The performance of organic‐inorganic hybrid solar cells (HSCs) can be improved by modifying the hole transport layer (HTL). Poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is the most active HTL material in organic‐inorganic HSCs and has been widely studied. Nevertheless, charge transfer in PEDOT:PSS is limited and inefficient due to the presence of the weak ionic conductor PSS. Moreover, the working function of the PEDOT:PSS film and the passivation of the PSS at the Si/PEDOT:PSS interface play a crucial role in carrier separation. The focus of this work is to explore a universal modification method to simultaneously achieve improved charge transport and interfacial passivation capability when using PEDOT:PSS as HTL. By combining bilayer design and simple solution posttreatment, the direct current conductivity (σdc) and work function of the HTL based on PEDOT:PSS are increased to 765 S cm−1 and 5.00 eV, respectively. The organic‐inorganic HSCs prepared using this approach achieve a photovoltaic conversion efficiency (PCE) of 12.33%, achieving a 16.54% improvement over untreated devices. [ABSTRACT FROM AUTHOR]

Compared with unicellular microalgae, filamentous algae have high resistance to grazer-predation and low-cost recovery in large-scale production. Green algae, as the most diverse group of algae, included numerous filamentous genera and species. In this study, records of filamentous genera and species in green algae were firstly censused and classified. Then, seven filamentous strains subordinated in different genera were cultivated in bubbled-column to investigate their growth rate and energy molecular (lipid and starch) capacity. Four strains including Stigeoclonium sp., Oedogonium nodulosum , Hormidium sp. and Zygnema extenue were screened out due to their robust growth. And they all could accumulate triacylglycerols and starch in their biomass, but with different capacity. After nitrogen starvation, Hormidium sp. and Oedogonium nodulosum respectively exhibited high capacity of lipid (45.38% in dry weight) and starch (46.19% in dry weight) accumulation, which could be of high potential as feedstocks for biodiesel and bioethanol production. [ABSTRACT FROM AUTHOR]

This paper deals with a nonlinear diffusion equation with double free boundaries possessing different moving parameters. We present the spreading–vanishing dichotomy and threshold between spreading and vanishing. Moreover, when spreading happens, using the zero number argument we provide sharp estimates of spreading speeds of expanding fronts, and describe how the solution approaches the semi-wave. [ABSTRACT FROM AUTHOR]

Gallic acid modified and reduced graphene coated by polydopamine (DM-GO) is synthesized. The results show that gallic acid can reduce graphene oxide and promote the stable dispersion of graphene in solution, and repair some defects of graphene surface through π-π interactions. Polydopamine can effectively mitigate serious corrosion caused by graphene due to its high electrical conductivity. Because of the barrier effect of well-dispersed graphene and the presence of polydopamine, the addition of DM-GO into waterborne coating leads to the significant improvement of the adhesion and long-term corrosion resistance of coatings. • Gallic acid can modify graphene oxide to obtain stable dispersion of graphene in water with low cost. • Gallic acid repaired some defects of graphene surface by pushing into them through π-π interactions. • Polydopamine solved the serious electrochemical problems that graphene may cause due to its high electrical conductivity. • The coatings adding DM-GO had excellent physical isolation performance, adhesion strength and corrosion protection. [ABSTRACT FROM AUTHOR]

• Polyelectrolyte-grafted anion exchangers with underlying hydrophilic layers. • Improvement in grafting effectiveness via successive grafting method. • Carboxylic intermediate layers substantially reduce both capacity and hydrophobicity. • Hydroxylic intermediate layers temperately reduce hydrophobicity. • Separation of multiple anionic components by suppressed anionic chromatography. The hydrophobicity of polymer-based anion exchangers is a persistent problem in suppressed anionic chromatography (SAC) due to its adverse effect on chromatographic performance. Herein we describe polyelectrolyte-grafted anion exchangers with modified hydrophilic intermediate layers. The anion exchangers were functionalized by successively grafting a linear cationic condensation polymer (LCCP), a preprepared polyelectrolyte. The carboxylic/hydroxylic intermediate layers formed during thiol-radical-mediated polymerization exert distinct effects on the phase capacity and hydrophobicity. The separation of typical inorganic anions, polarizable anions, and organic acids shows that the anion exchangers display good performance in SAC mode. [ABSTRACT FROM AUTHOR]

This paper deals with a semilinear parabolic system with reaction terms $${v^p, u^q}$$ and a free boundary $${x = s(t)}$$ in one space dimension, where $${s(t)}$$ evolves according to the free boundary condition $${s'(t) = -\mu(u_x + \rho v_x)}$$ . The main aim of this paper was to study the existence, uniqueness, regularity and long-time behavior of positive solution (maximal positive solution). Firstly, we prove that this problem has a unique positive solution when $${p, q \geq 1}$$ , and a (unique) maximal positive solution when $${p < 1}$$ or $${q < 1}$$ . Then, we study the regularity of $${(u,v)}$$ and $${s}$$ . At last, we discuss the global existence, finite-time blowup of the unique positive solution (maximal positive solution) and long-time behavior of bounded global solution. [ABSTRACT FROM AUTHOR]

Identifying the origins of uranium ore concentrates (UOCs) has become a research hotspot in nuclear forensics. In the present study, a novel approach using the REE data of uranium ores instead of UOC samples was established to trace the origins of unknown UOCs with the help of iterative OLPS-DA. In this paper, a database was established by gathering published REE data of uranium ores from different countries. The data were transformed by a two-step pretreatment so that they could show stronger geographical and geological indications, and the REE patterns of uranium ores could be compared with each other, as well as those of the unknown UOCs. The efficiencies of different multidimensional statistical techniques in pattern recognition, including principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) and orthogonal partial least squares discriminant analysis (OPLS-DA), were compared, and the results showed that the OPLS-DA was the most effective method when distinguishing uranium ores from different origins in the scatter diagrams. With the help of iterative OPLS-DA, samples from 10 different countries were totally distinguished within several iterations, and the discrimination orders formed a decision tree or an attribution strategy. The results indicated that it was feasible to attribute an unknown UOC to its country, deposit and type of uranium ore by comparing the unknown UOC with uranium ores from different origins according to the decision tree. Eventually, this study verifies that REE pattern is a powerful geographical and geological indicator when identifying the origin of UOC by analysing REE data of uranium ores from different origins with the help of iterative OLPS-DA, and OLPS-DA has better potential in nuclear forensics studies compared to PCA and PLS-DA, which provides support to fight against the illicit trafficking of nuclear materials. [ABSTRACT FROM AUTHOR]

• Corrosion resistance of 3Cr steel was first reduced, followed by enhancing and then reduced as the rotation speed increased. • Silty sand changed from participating in the corrosion film to destroying the corrosion film. • Increasing rotation speed converted a factor that played a dominant role in corrosion resistance from mass transfer process to shear stress of silty sand. • Critical rotation speed for corrosion mechanism transformation of 3Cr steel was 600 r/min. The 3Cr steel used as the tubing has serious corrosion damage in a flowing CO 2 environment with silty sand. Hence, the investigation for the influence of flow velocity on the corrosion behavior of 3Cr steel has an important and practical significance. It could not only unveil the corrosion damage mechanism of the steel under dynamic conditions, but also provide a theoretical basis for the corrosion protection of the tubing. In this paper, the effect of flow velocity on the corrosion film of 3Cr steel in a CO 2 environment with silty sand was investigated by adjusting rotation speed. The results revealed that the corrosion resistance of 3Cr steel was first reduced, followed by enhancing and then reduced as the rotation speed increased. There was a critical rotation speed for the transformation of corrosion mechanism of 3Cr steel, i.e., 600 r/min. When the rotation speed was lower than the critical speed, the mass transfer process of corrosive medium dominated the corrosion resistance of 3Cr steel, and silty sand participated in the formation of corrosion film. The increasing rotation speed accelerated the mass transfer process, which first reduced and then improved the corrosion resistance. When the rotation speed was higher than the critical speed, the shear stress of silty sand played a predominant role. At the same time, silty sand impinged on the corrosion film, and then destroyed the stability of the film, leading to a significant decrease of the corrosion resistance. Silty sand changed from participating in the corrosion film to destroying the corrosion film with increasing rotation speed. [ABSTRACT FROM AUTHOR]

Effects of the magnetic field on propagation characteristics of thickness-twist waves in inhomogeneous plates consisting of piezomagnetic material and elastic material are investigated in the article. The effective material constants of the piezomagnetic materials are changed by the magnetic field. Based on the continuity condition at the interface between the piezomagnetic materials and elastic materials, the displacement components and amplitude ratios of the reflected waves to incident waves are obtained. The numerical results show that the energy trapping phenomenon, which does not exist in the proposed structures, is generated by the magnetic field, and the reflected waves disappear under certain combination of the incident frequency and magnetic field. The results in the article are of great significance for designing resonators and other magneto-elastic acoustic devices. [ABSTRACT FROM AUTHOR]

Abstract: Vabicaserin, a potent 5-HT2C receptor agonist, decreases nucleus accumbens extracellular dopamine levels in rats, without affecting striatal dopamine, indicating mesolimbic selectivity. This is the first study of efficacy, safety and tolerability of vabicaserin in adults with acute schizophrenia. Three hundred fourteen hospitalized subjects were randomized to: Vabicaserin 200 or 400 mg/day, olanzapine 15 mg/day or placebo. Central raters assessed the PANSS and CGI-S. Site raters performed the BPRS and CGI-I. Central rated PANSS Positive (PANSS-PPS) was the primary endpoint. Two hundred eighty-nine subjects were included in the mITT efficacy analysis. Vabicaserin was well tolerated with no major safety concerns. Olanzapine, but not vabicaserin, caused weight gain. Vabicaserin 200 mg/day and olanzapine demonstrated significant improvement at week 6 vs. placebo on PANSS-PSS. A non-significant decrease vs. placebo was observed for 400 mg/day. Both vabicaserin groups demonstrated significant improvement over baseline on PANSS Negative while placebo worsened. Vabicaserin 200 mg/day and olanzapine demonstrated significantly greater improvement over placebo on PANSS Total whereas 400 mg/day showed a trend toward improvement. There was no significant improvement vs. placebo for either vabicaserin group on site-rated BPRS. Vabicaserin 200 mg/day and olanzapine demonstrated significant improvement vs. placebo on CGI-I and CGI-S but not 400 mg/day vabicaserin. Vabicaserin demonstrated efficacy on primary and secondary endpoints at 200 mg/day, but not at 400 mg/day which showed a trend for efficacy. The 200 mg/day vabicaserin group achieved proof of concept using central ratings. Both vabicaserin doses were well tolerated with no significant safety signals and no weight gain. Trial Registration: clinicaltrials.gov. Identifier: NCT00265551. [Copyright &y& Elsevier]

Highlights: [•] Soil infiltrability varied along a 79-year natural restoration chronosequence. [•] Grassland restoration reduced impact of high-intensity rainfall on infiltrability. [•] Soil infiltrability increased over time during natural restoration on Loess Plateau. [•] Organic matter accumulation improved soil structure and infiltrability. [ABSTRACT FROM AUTHOR]

We report two new 3D structures, [Zn3(bpdc)3(2,2′-dmbpy)] (DMF) x(H2O) y ( 1) and [Zn3(bpdc)3(3,3′-dmbpy)]⋅(DMF)4(H2O)0.5 ( 2), by methyl functionalization of the pillar ligand in [Zn3(bpdc)3(bpy)] (DMF)4⋅(H2O) ( 3) (bpdc=biphenyl-4,4′-dicarboxylic acid; z, z′-dmbpy= z, z′-dimethyl-4,4′-bipyridine; bpy=4,4′-bipyridine). Single-crystal X-ray diffraction analysis indicates that 2 is isostructural to 3, and the power X-ray diffraction (PXRD) study shows a very similar framework of 1 to 2 and 3. Both 1 and 2 are 3D porous structures made of Zn3(COO)6 secondary building units (SBUs) and 2,2′- or 3,3′-dmbpy as pillar ligand. Thermogravimetric analysis (TGA) and PXRD studies reveal high thermal and water stability for both compounds. Gas-adsorption studies show that the reduction of surface area and pore volume by introducing a methyl group to the bpy ligand leads to a decrease in H2 uptake for both compounds. However, CO2 adsorption experiments with 1′ (guest-free 1) indicate significant enhancement in CO2 uptake, whereas for 2′ (guest-free 2) the adsorbed amount is decreased. These results suggest that there are two opposing and competitive effects brought on by methyl functionalization: the enhancement due to increased isosteric heats of CO2 adsorption ( Qst), and the detraction due to the reduction of surface area and pore volume. For 1′, the enhancement effect dominates, which leads to a significantly higher uptake of CO2 than its parent compound 3′ (guest-free 3). For 2′, the detraction effect predominates, thereby resulting in reduced CO2 uptake relative to its parent structure 3′. IR and Raman spectroscopic studies also present evidence for strong interaction between CO2 and methyl-functionalized π moieties. Furthermore, all compounds exhibit high separation capability for CO2 over other small gases including CH4, CO, N2, and O2. [ABSTRACT FROM AUTHOR]

Microporous metal–organic frameworks (MOFs) have attracted tremendous attention because of their versatile structures and tunable porosity that allow almost unlimited ways to improve their properties and optimize their functionality, making them very promising for a variety of important applications, especially in the adsorption and separation of small gases and hydrocarbons. Numerous studies have demonstrated that MOFs with multifunctional groups, such as open metal sites (OMSs) and Lewis basic sites (LBSs), interact strongly with carbon dioxide and are particularly effective in its capture and separation from binary mixtures of CO2 and N2. In this feature article, we briefly review the current state of MOF development in this area, with an emphasis on the effect of multifunctional groups on the selectivity and capacity of MOFs for the CO2 capture from flue gas mixtures. [ABSTRACT FROM AUTHOR]

Abstract: We study positive solutions of the following system of integral equations related to the weighted Hardy–Littlewood–Sobolev inequality: where , , , , and . We obtain regularity of the solutions by regularity-lifting-method, which has been extensively used by many authors. Moreover, using the method of moving planes in integral forms, we also establish symmetry of the solutions under the weaker condition that u and v are only locally integrable. [Copyright &y& Elsevier]

Abstract: A TiO2/Pt based electrode exhibited better activity for the oxidation of coal in a basic system compared to Ti/Pt, TiO2–Cu/Pt and pure metal electrodes. The surface morphologies and composition of the electrodes were studied by SEM and XRD, respectively. Linear sweep voltammetry was employed to investigate the catalytic effects of electrodes, and the product of coal oxidization was determined by a gas collection test. The TiO2/Pt electrodes that were modified with NiO and/or Co3O4 exhibited higher average currents and a lower decrease in mass during electrolysis compared to the other electrodes; this finding indicated that NiO and Co3O4 play important roles as catalysts. [Copyright &y& Elsevier]

Abstract: Electrocatalytic oxidation of coal on Ti-supported metal/metal oxides coupled with liquid catalysts is systematically investigated as a method of producing hydrogen at the cathode. The composition of the liquid catalyst was varied to determine its effect on the coal electrolysis. A spectrum of byproducts from the coal oxidation at the anode was analyzed. The Ti-supported metal oxide electrodes were prepared by thermal decomposition and characterized by scanning electron microscopy (SEM). X-ray diffraction results show that the composition of the electrodes was Ti/Pt, Ti/RuO2, Ti/IrO2 and Ti/IrO2–RuO2. Coal oxidation tests on these electrodes indicate that Ti/IrO2 has the best electrocatalytic activity. Polarization curves reveal that redox catalysts, such as Fe3+, K3Fe(CN)6, KBr and V2O5, bridge the coal particles and the solid electrode surface, thus increasing the rates of coal oxidation. The dynamic transition of Fe3+/Fe2+ is proven by a KMnO4 titration experiment, and the possible catalytic mechanism is discussed. Product analysis shows that pure H2 is generated at the cathode and that CO2 is the main product at the anode. [Copyright &y& Elsevier]

Abstract: This note is concerned with a surface semi-circular crack by using finite element method. Attention is specifically paid to the effect of the boundaries parallel to the crack on the stress intensity factors (SIFs). The numerical results illustrate that when the boundaries parallel to the crack are closer to the crack surface the effect of the boundaries parallel to the crack on the SIFs must be considered. [Copyright &y& Elsevier]

• The Volta potential of Cr-depleted regions was lower than that of steel matrix and the regions were dissolved preferentially. • Increasing Cr contents in the Cr-depleted regions hampered the effect of Cr deficiency in the weak passive film. • Low width and density of Cr-depleted regions reduced the intensity of pits on steel surface. • High Cr contents and low Cr-depleted regions width and density led to good pitting corrosion resistance for 0Cr13 MSS. The effect of M 23 C 6 precipitates on the pitting behavior of 0Cr13 martensitic stainless steel (MSS) was investigated. The results revealed that the precipitates in the 0Cr13 MSS with different tempering temperatures were all M 23 C 6 with a face-centered cubic (FCC) structure. The Cr-depleted regions had approximately 6 mV Volta potential lower than the steel matrix. The increasing Cr contents in the Cr-depleted regions hampered the effect of Cr deficiency in the weak passive film. The low width and density of Cr-depleted regions reduced the intensity of pits on steel surface. The pitting corrosion resistance was enhanced as the tempering temperature increased. [ABSTRACT FROM AUTHOR]

Abstract: Electroporation can improve intramuscular DNA vaccination efficacy but the exact antigen presentation mechanism remains unclear. We reported here that a similar immuno-potentiation effect was also observed by stimulating the skeletal muscles with electric pulses (EP) a few days prior to DNA inoculation (EP+ n days+DNA). The application of EP by itself activated proinflammatory chemokine genes and stress genes. It also triggered an influx of inflammatory monocytes/macrophages (MPs). After DNA inoculation, the plasmids were seen taken up by these inflammatory MPs, which migrated to the draining LNs subsequently. The antibody responses results were fast and strong. Furthermore, MPs isolated from the draining LNs of EP+ n days+DNA treated mice were capable of stimulating Ag specific CD4+ T cell proliferation in vitro. Based on these observations, we proposed that the local inflammation resulted from EP treatment played an important role in facilitating antigen presentation of the DNA vaccines. [Copyright &y& Elsevier]

Abstract: A highly selective fluorogenic signaling fluoride-sensor Ru-HL, comprised of Ru-bipy moiety (bipy=2,2′-bipyridine) and 3-hydroxyl-2-naphthoylhydrazine was prepared and structurally characterized. The fluorescence spectra titration revealed the high selectivity and sensitivity of Ru-HL for F− through an excited-state intermolecular proton transfer (ESPT) signaling transduction mechanism. [Copyright &y& Elsevier]

Abstract: In vivo plasmid DNA electroporation resulted in elevated and lasting transgene expression in skeletal muscles. But the nature of the cells that contributed to sustained gene expression remains unknown. We followed the fate of plasmid DNA delivered with electroporation and systematically investigated the time course and location of transgene expression in muscle tissues both with GFP and luciferase. Furthermore, satellite cell activation after electroporation was confirmed by RT-PCR and immunohistochemistry analysis. The activated satellite cells were shown to be able to uptake the injected plasmid DNA and express transgene products as regenerated myocytes. We found that cells with longer gene expression durations were mostly regenerated muscle fibers. In contrast, expression in pre-existing muscle fibers was rather transient. We also presented in this study that immune response to transgene products might hamper the lasting gene expression. Based on these observations, we proposed that the underlying mechanism for prolonged transgene expression in the muscles after electroporation is related to the activation and transfection of myogenic satellite cells which subsequently developed into regenerated muscle fibers. [Copyright &y& Elsevier]

The hydrodenitrogenation (HDN) of n-hexylamine, dihexylamine, and trihexylamine was studied between 300 and 340 °C, 3 and 5 MPa total pressure, 5 and 20 kPa amine pressure, and 10 and 150 kPa H2S pressure over a sulfided Ni–Mo/γ-Al2O3 catalyst. The conversion increased with the H2 pressure and decreased with increasing partial pressure of the hexylamines. The conversion of hexylamine and dihexylamine decreased slightly with H2S pressure, but that of trihexylamine increased substantially. The contributions of elimination and nucleophilic substitution to the HDN were determined by the initial product selectivities at short weight time. The initial alkene selectivities were low and accounted for only a minor part of the n-alkylamine conversion. Since the hexene/hexane branching ratio in the HDN of the alkylamines was almost equal to that in the hydrodesulfurization of pentanethiol in the presence of an alkylamine, it was concluded that the majority of hexene in the HDN of the hexylamines originates from hexanethiol. Nucleophilic substitution of the hexylamines with H2S to give an alkanethiol is the predominant HDN reaction of all three n-hexylamines. [Copyright &y& Elsevier]

The effect of microstructure on the corrosion characteristics of super 13Cr martensitic stainless steel (S13Cr MSS) under heat treatment was investigated. The results revealed that the Ni enriched reversed austenite content in the tempered steel increased as the tempering temperature increased. No Mo-rich intermetallic compounds and reversed austenite were found in the quenched steel. The Mo-rich intermetallic compounds adversely affected the protective properties of the corrosion film because the Mo-depleted regions adjacent to the compounds had approximately 7 mV Volta potential lower than steel matrix, destroying the corrosion film stability. However, the reversed austenite benefitted on the corrosion film due to it inhibiting further corrosion of S13Cr MSS and enhancing the corrosion film stability. Accordingly, the quenched steel without Mo-rich intermetallic compounds had the highest corrosion resistance and the corrosion resistance of the tempered steel increased with an increasing tempering temperature. [Display omitted] • Ni enriched reversed austenite content increased as the tempering temperature increased. • Mo-depleted regions had the lower Volta potential than steel and the regions destroyed the corrosion film stability. • Reversed austenite inhibited further corrosion of S13Cr MSS and enhanced the corrosion film stability. • Mo-rich intermetallic compounds adversely affected corrosion film, while reversed austenite had a beneficial effect. [ABSTRACT FROM AUTHOR]

Topologically protected domains, composed of mutually coupled ferroelectric, (anti)ferromagnetic, and antiphase domains, are widespread in hexagonal manganites. We have applied the extended Howie-Whelan equations in hexagonal systems and simulated the electron-diffraction intensities of four kinds of representative hexagonal manganites. Thereby, the polarization directions of domains and charging status of domain walls can be easily determined by electron-diffraction contrast method, which is succinct and reliable. Here, we present a systematic investigation about the polarization structures and pave the way for further study about the properties of domains by transmission electron microscopy. Besides, the dynamic behavior of domains merely under transmission electron beam irradiation was firstly shown as well. [ABSTRACT FROM AUTHOR]

In recent years, there is significant interest in Cu 2 SnS 3 (CTS) thin film solar cells owing to the eco-friendly nature and abundant elemental composition. However, the efficiency prepared in laboratory settings for these solar cell remains relatively low, primarily due to serious open-circuit voltage losses. Cation substitution is one of the strategies to alleviate this problem. In this work, Ag and Ge dual-cation substitution in CTS is proposed, which occupy partial Cu and Sn lattice sites respectively. Investigation reveals that substituting Cu with part Ag increases the band gap slightly, promotes grain growth, and improves crystallinity of CTS films. Simultaneously, Ge incorporation shifts the conduction band upwards to some extent, while reducing grain boundaries, due to increasing the grain size. As a result, the incorporation of 6 % Ag resulted in an optimal efficiency (PCE) of 2.78 %. Furthermore, employing dual-cation substitution with 6 % Ag and 6 % Ge is employed, the CTS device achieved an optimal efficiency of 3.15 %. This work develops the synergistic effect of Ag and Ge dual-cation substitution in CTS device and confirms that this approach can improve device performance, thus providing new research ideas for advancing the development of CTS device. • Preparation of ternary compound Cu 2 SnS 3 thin film solar cells by solution method. • Improve the crystal quality by adding different concentrations of Ag into the Cu 2 SnS 3 absorption layer. • Incorporated different amounts of Ge to Cu 2 SnS 3 absorber layer with containing 6 % Ag to obtain solar cells with higher efficiency. [ABSTRACT FROM AUTHOR]

Characterizing the microscopic pore systems in shale reservoirs is crucial for understanding their impact on shale oil and gas enrichment. Although significant strides have been made in understanding the pore structure characteristics, research on pore structures related to small-scale sedimentary structures remains limited. This study investigated the multi-scale nanopore structure characterization and its coupling relationship with sedimentary structures using comprehensive analyses of cores, field-emission scanning electron microscopy, and gas (CO2 and N2) physisorption quantification from the Upper Cretaceous Qingshankou Formation, Southern Songliao Basin, NE China. Three lithofacies were identified based on sedimentary structures: wavy laminated shale, horizontally laminated shale, and homogeneously laminated shale. Both organic and inorganic pores (interparticle pores and intraparticle pores) are generally present in shale samples. The pore size distribution displays a multi-peak pattern, with mesopores contributing to approximately 57% of the total pore volume, micropores contributing to about 31%, and macropores accounting for a small portion of the total pore volume. The pore evolution of different lithofacies shales varies due to the influence of clay minerals, quartz content, and total organic carbon (TOC) content, resulting in the substantial heterogeneity and complex pore structure characteristics of existing reservoirs. Additionally, wavy laminated shales are more favorable to lacustrine shale exploration than other lithofacies. This study offers an enhanced methodology for determining which lithofacies may be most advantageous for future shale oil exploitation. [ABSTRACT FROM AUTHOR]

A new metal organic framework containing high density of active Cu sites demonstrates 100% oxidative conversion of CO to CO2. [ABSTRACT FROM AUTHOR]

• High Fe 3 C content accelerated the formation of a passive film on the Cr steel surface in silty sand containing solution. • Increasing Cr content in steel enhanced the contents of Cr 2 O 3 and Cr(OH) 3 in the passive film. • Silty sand increased carrier densities of the passive films and reduced the protective effects of the films. • Corrosion mechanism of the Cr steel with silty sand based on the combined effect of Fe 3 C and Cr contents was illustrated. The effect of Cr content in steel on its passivation behavior in a CO 2 aqueous environment containing silty sand was investigated. The results indicated that the stability of passive film was improved with increasing Cr content. High Fe 3 C content accelerated the rapid formation of a passive film as well as precipitates and dislocations. Increasing Cr content enhanced the contents of Cr 2 O 3 and Cr(OH) 3 in the passive film. Silty sand increased carrier densities of passive films, thereby reducing their protective effects. The role of the contents of Fe 3 C and Cr on corrosion mechanism of Cr steel with silty sand was emphasized. [ABSTRACT FROM AUTHOR]

Abstract: A novel fluorescent sensor was prepared and used as an ion-selective chemosensor for Al(III) via intramolecular excimer formation, from which a significant red shift along with an intensity enhancement of the excimer emission was observed in the presence of Al(III). [Copyright &y& Elsevier]

It is still an open issue to measure uncertainty of the basic probability assignment function under Dempster-Shafer theory framework, which is the foundation and preliminary work for conflict degree measurement and combination of evidences. This paper proposes an improved belief entropy to measure uncertainty of the basic probability assignment based on Deng entropy and the belief interval, which takes the belief function and the plausibility function as the lower bound and the upper bound, respectively. Specifically, the center and the span of the belief interval are employed to define the total uncertainty degree. It can be proved that the improved belief entropy will be degenerated to Shannon entropy when the the basic probability assignment is Bayesian. The results of numerical examples and a case study show that its efficiency and flexibility are better compared with previous uncertainty measures. [ABSTRACT FROM AUTHOR]