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Abstract The Japanese anchovy (Engraulis japonicus), a finfish with the largest biomass of a single species in the Yellow and East China Seas, plays an important pivotal role in converting zooplanktons into high trophic fish in the food web. As a result, the fish is regard as a key species in its habiting ecosystem. However, the lack of genomic resources hampers our understanding of its genetic diversity and differentiation, as well as the evolutionary dynamics. Here, we firstly report a complex chromosome-level genome assembly of E. japonicus with a large size of 1.4 Gb, with features of high repetitive sequences (54.9%), high heterozygosity (2.3%) and a number of protein-coding genes (24,405). The genome sequence exhibited a remarkable degree of completeness, valued 94.07% of the complete BUSCO. This work firstly reported the genome sequence of E. japonicus, offering the crucial resources for further studies on the genetic diversity and adaptive evolution of this species.

With the rapid development of 5G/6G communications, new energy vehicles, and lithium battery industries, the demand for lithium compounds (especially Li2CO3) has dramatically increased in recent years. Many countries have regarded lithium as a strategic mineral resource. Lithium is mainly found in liquid mineral resources around the world, and the extraction of lithium from the mother liquor of lithium precipitates has thus garnered significant attention. The main methods for recovering lithium from solutions include membrane separation, solvent extraction, electrochemistry, and adsorption. Among them, the adsorption method is one of the most promising. The key to successful adsorption technology is the construction of high-performance adsorbents with high adsorption capacity, high ionic selectivity, and high structural stability. The manganese-ion sieve named as LMO, is a promising adsorbent that has been widely studied because of its good chemical stability, excellent adsorption properties, and outstanding ion selectivity for lithium extraction. However, its inherent dissolution loss greatly restricts its practical application. To reduce the dissolution loss of manganese-ion sieves, several strategies, such as adjusting the synthesis process, composition optimization, ion doping, and surface modification, were adopted. This study introduces Co3+ doping to mitigate manganese loss in LMO, resulting in the preparation of cobalt-doped manganese-based ion sieves (LCMO). LCMOs prepared at various calcination temperatures and times were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy, and X-ray photoelectron spectroscopy (XPS). The XRD characterization results indicate that Co doping has no effect on the spinel structure of LMO. The SEM results confirmed the successful doping and uniform Co distribution in LCMO-5%. The XPS results show that a Co doping molar fraction of 5% can reduce the content of Mn3+ from 9.67% in the undoped precursor to 3.63%, which may be because the partial substitution of Mn3+ by Co3+ reduces the proportion of Mn3+. The lithium adsorption capacity increased from 39.299 to 41.708 mg·g−1, and the manganese dissolution significantly decreased from 1.288% to 0.84%. The performance improvement of the LCMO greatly promotes the practical application of manganese-based ion sieves. The prepared 5% molar fraction of the Co-doped ion sieve (LCMO-5%) exhibited excellent cycling performance, and the adsorption efficiency of Li+ remained above 81% after five cycles. In the simulated lithium precipitation mother liquor, the separation coefficients of Li/Na and Li/K were 74.655 and 64.547, respectively, indicating that LCMO-5% effectively adsorbed Li+ from solutions containing high concentrations of Na+ and K+. Therefore, the LCMO-5% ion sieve exhibits outstanding application prospects for Li+ extraction from liquid lithium resources.

As the basic protective element, steel plate had attracted world-wide attention because of frequent threats of explosive loads. This paper reports the relationships between microscopic defects of Q345 steel plate under the explosive load and its macroscopic dynamics simulation. Firstly, the defect characteristics of the steel plate were investigated by stereoscopic microscope (SM) and scanning electron microscope (SEM). At the macroscopic level, the defect was the formation of cave which was concentrated in the range of 0–3.0 cm from the explosion center, while at the microscopic level, the cavity and void formation were the typical damage characteristics. It also explains that the difference in defect morphology at different positions was the combining results of high temperature and high pressure. Secondly, the variation rules of mechanical properties of steel plate under explosive load were studied. The Arbitrary Lagrange-Euler (ALE) algorithm and multi-material fluid-structure coupling method were used to simulate the explosion process of steel plate. The accuracy of the method was verified by comparing the deformation of the simulation results with the experimental results, the pressure and stress at different positions on the surface of the steel plate were obtained. The simulation results indicated that the critical pressure causing the plate defects may be approximately 2.01 GPa. On this basis, it was found that the variation rules of surface pressure and microscopic defect area of the Q345 steel plate were strikingly similar, and the corresponding mathematical relationship between them was established. Compared with Monomolecular growth fitting models (MGFM) and Logistic fitting models (LFM), the relationship can be better expressed by cubic polynomial fitting model (CPFM). This paper illustrated that the explosive defect characteristics of metal plate at the microscopic level can be explored by analyzing its macroscopic dynamic mechanical response.

The zinc smelting industry is a major source of atmospheric mercury emissions in China. It is crucial to develop a low-cost technology to reduce mercury pollution emissions for the green development of zinc smelting. Thus, based on the concept of “using waste to treat waste”, this study uses high-sulfur slag and secondary zinc oxide, which are produced in the zinc smelting process as raw materials, to prepare zinc sulfide adsorbent by high-temperature sulfurization in an inert atmosphere. The zinc sulfide adsorbents prepared under different roasting temperatures and time were characterized and analyzed by various analysis methods, including X-ray diffraction (XRD), Raman spectroscopy (Raman), scanning electron microscopy (SEM) and specific surface area analysis (BET). The effects of various reaction times and flue gas components on the mercury removal performance were studied. The experimental results reveal that the zinc sulfide adsorbent can be successfully prepared when the roasting temperature and holding time are more than 250 ℃ and 60 min, respectively. Under this condition, many mesoporous holes are formed. The prepared ZnS–250 ℃–90 min adsorbent has the best performance for Hg0 adsorption. Moreover, gaseous elemental mercury (Hg0) has an average adsorption efficiency above 98% at flue gas temperatures below 150 ℃, and it exhibits high resistance to O2, SO2, and H2O. When the Hg0 adsorption efficiency decreased to 50%, the Hg0 adsorption capacity of ZnS–250 ℃–90 min was 3.04 mg·g−1 in the simulated zinc smelting flue gas atmosphere, which is superior to conventional metal sulfides for Hg0 adsorption. Furthermore, the Hg0 adsorption on the surface of ZnS adsorbent is a chemical adsorption process, and the unsaturated short-chain sulfur on the surface of ZnS adsorbent is the critical active site, which can react with Hg0 to form stable HgS, thus realizing the high-efficiency purification of Hg0 from smelting flue gas. Furthermore, the spent ZnS adsorbent can be regenerated using thermal desorption and polysulfide impregnation. An excellent cycle performance for Hg0 capture is realized, and the Hg0 adsorption efficiency remains above 99% after five cycles. Simultaneously, the desorbed mercury can be recycled as elemental mercury by condensation during the regeneration process of ZnS adsorbent. Thus, this study not only provides a low-cost method for mercury pollution control and resource recovery from the zinc smelting industry but also supports the cyclic utilization of typical waste produced in the zinc smelting industry, promoting the green production of the zinc smelting industry.

With the rise of economic and safety standards for nuclear reactors, new concepts of Gen-IV reactors and modular reactors showed more complex designs that challenge current tools for reactor physics analysis. A Monte Carlo (MC) two-step method was proposed in this work. This calculation scheme uses the continuous-energy MC method to generate multi-group cross-sections from heterogeneous models. The multi-group MC method, which can adapt locally-heterogeneous models, is used in the core calculation step. This calculation scheme is verified using a Gen-IV modular lead-based fast reactor (LFR) benchmark case. The influence of homogenized patterns, scatter approximations, flux separable approximation, and local heterogeneity in core calculation on simulation results are investigated. Results showed that the cross-sections generated using the 3D assembly model with a locally heterogeneous representation of control rods lead to an accurate estimation with less than 270 pcm bias in core reactivity, 0.5% bias in control rod worth, and 1.5% bias on power distribution. The study verified the applicability of multi-group cross-sections generated with the MC method for LFR analysis. The study also proved the feasibility of multi-group MC in core calculation with local heterogeneity, which saves 85% time compared to the continuous-energy MC.

In this work, Ce-doped Ti6Cr14V80 BCC hydrogen-storage alloys have been synthesized as catalysts to enhance the hydrogen-storage performance of MgH2 based on its room-temperature activation features and excellent durability. The Ti6Cr14V80Ce1 alloy was pre-ball milled under a hydrogen atmosphere into a Ti6Cr14V80Ce1Hx hydride. Different amounts of the Ti6Cr14V80Ce1Hx hydride were incorporated into MgH2 by ball milling to obtain the MgH2 + y wt%Ti6Cr14V80Ce1Hx (y = 0, 3, 5, 10, 15) nano-composites. With an optimization doping of 10 wt%Ti6Cr14V80Ce1Hx, the initial dehydrogenated temperature was decreased to 160 °C. Moreover, the composite can rapidly release 6.73 wt% H2 within 8 min at 230 °C. Also, it can absorb 2.0 wt% H2 within 1 h even at room temperature and uptake 4.86 wt% H2 within 10 s at 125 °C. In addition, the apparent dehydrogenated activation energy of the MgH2 + 10 wt%Ti6Cr14V80Ce1Hx composite was calculated to be 62.62 kJ mol−1 fitted by the JMAK model. The capacity retention was kept as 84% after 100 cycles at 300 °C. The ball milled Ti6Cr14V80Ce1Hx transformed from the initial FCC phase structure into a BCC phase after complete dehydrogenation and back into an FCC phase when fullly hydrogenated. A catalyst mechanism analysis revealed that the ‘autocatalytic effect’ originating in Ti6Cr14V80Ce1Hx plays a crucial role in boosting the de-/hydrogenation properties of MgH2. This work provides meaningful insights into rational designs of nano-compositing with different hydrogen-storage alloy catalyzed MgH2.

Self-healing microcapsules in the asphalt pavement must be kept intact under vehicle load to ensure there is enough rejuvenator in capsules when cracks appear in asphalt pavement. In this paper, the crack resistance of self-healing microcapsules in asphalt pavement was evaluated. Firstly, an expanding multi-scale analysis was conducted based on proposed mesoscopic mechanical models with the aim to determine the mechanical parameters for the following contracting multi-scale analysis. Secondly, the periodic boundary condition was introduced for the contracting multi-scale analysis and the stress field of the capsule wall was obtained. Finally, the effects of the design parameters of the microcapsule on its crack resistance in asphalt pavement were investigated. The results showed that the incorporation of microcapsules has almost no effect on the elastic constants of the asphalt mixture. The core could be simplified as an approximately incompressible solid with the elastic constants determined by the proposed mesoscopic mechanical model. With the increase of the modulus of the capsule wall, the mean maximum tensile stress of the capsule wall increased from 0.372 MPa to 0.465 MPa, while with the decrease of the relative radius of the capsule core, the mean maximum tensile stress of the capsule wall increased from 0.349 MPa to 0.461 MPa. The change in the mean maximum tensile stress of the capsule wall caused by the change of capsule diameter was within 5%. The relative radius of the capsule core and the elastic modulus of capsule wall were two key parameters in capsule design. Besides, the microcapsules with the wall made of resin would not crack under the vehicle load before microcracks occurred in asphalt pavement.

In this study, 5% wt Ce-containing sintered Pr/Nd-Ce-Fe-B magnets were processed by grain boundary diffusion (GBD) with NdxDy90-xAl10 alloy (x = 0, 10, and 20 correspond to N0, N10, and N20, respectively). After the GBD process, the coercivity of magnets increased from 1,124.7 to 1,656.4, 1,673.9, and 1,584.8 kA/m, for N0, N10, and N20, respectively. Microstructure analysis revealed continuous RE-rich intergranular phases around matrix grains, which by weakening the magnetic coupling effect between ferromagnetic matrix grains, thus, leads to coercivity improvement. N10 had the same coercivity enhancement as N0, while the Dy utilization for N10 is lower than that for N0. The SEM results showed that the inclusion of Nd leads to the formation of a network of low-melting grain boundary phases, providing channels for subsequent Dy diffusion. A CeFe2 phase was found in the 5% wt Ce-containing magnet, which hindered diffusion due to its high melting point; in order to inhibit the negative impact of CeFe2 and reveal the diffusion mechanism in the Ce-containing magnet, DyH3, as a diffusion source, was applied to 5% wt-Ce-containing magnets simultaneously; after the GBD process, Nd10Dy90Al10 alloy, as a diffusion source, has better coercivity enhancement than DyH3, due to the deeper diffusion of the Dy element in the Nd10Dy90Al10 diffusion.

Abstract Alzheimer’s disease (AD) poses an ever-increasing public health concern as the population ages, affecting more than 6 million Americans. AD patients present with mood and sleep changes in the prodromal stages that may be partly driven by loss of monoaminergic neurons in the brainstem, but a causal relationship has not been firmly established. This is due in part to a dearth of animal models that recapitulate early AD neuropathology and symptoms. The goal of the present study was to evaluate depressive and anxiety-like behaviors in a mouse model of AD that overexpresses human wild-type tau (htau) prior to the onset of cognitive impairments and assess these behavior changes in relationship to tau pathology, neuroinflammation, and monoaminergic dysregulation in the dorsal raphe nucleus (DRN) and locus coeruleus (LC). We observed depressive-like behaviors at 4 months in both sexes and hyperlocomotion in male htau mice. Deficits in social interaction persisted at 6 months and were accompanied by an increase in anxiety-like behavior in males. The behavioral changes at 4 months coincided with a lower density of serotonergic (5-HT) neurons, downregulation of 5-HT markers, reduced excitability of 5-HT neurons, and hyperphosphorylated tau in the DRN. Inflammatory markers were also upregulated in the DRN along with protein kinases and transglutaminase 2, which may promote tau phosphorylation and aggregation. Loss of 5-HT innervation to the entorhinal cortex and dentate gyrus of the hippocampus was also observed and may have contributed to depressive-like behaviors. There was also reduced expression of noradrenergic markers in the LC along with elevated phospho-tau expression, but this did not translate to a functional change in neuronal excitability. In total, these results suggest that tau pathology in brainstem monoaminergic nuclei and the resulting loss of serotonergic and/or noradrenergic drive may underpin depressive- and anxiety-like behaviors in the early stages of AD.

Constructing advanced nanostructures and combining various active materials are effective strategies to obtain high-performance anode materials for lithium-ion batteries (LIBs). Herein, we report a surface-coordinated polymerization method to synthesize ZIF-67 nanoparticles with a reuleaux tetrahedron morphology, and combine the electrostatic adsorption method and heat treatment, nitrogen-doped hollow porous Co3O4 (HP-Co3O4/NC) nanoparticles were anchored on reduced graphene oxide (rGO) to obtain HP-Co3O4/NC@rGO composites. This deliberate structural design can significantly improve the electrochemical performance of lithium (Li) storage. When applied as an anode material in LIBs, HP-Co3O4/NC@rGO nanocomposite renders a reversible capacity of 809 mAh g−1 after 200 charge/discharge cycles at a current density of 1000 mA g−1. The excellent electrochemical performance is mainly attributed to the synergistic effect of the hollow nanostructure and graphene network. A hollow nanostructure can provide abundant active sites and enhance structural stability. As a conductive network, graphene tightly wraps Co3O4, which can not only increase the electronic and ionic transport but also alleviates the volumetric changes of Co3O4 during the charge/discharge process, thereby improving the rate performance and cyclic stability.

Abstract Mood disorders, including anxiety and depression caused by prenatal ethanol exposure (PE) are prevalent conditions in fetal alcohol spectrum disorders (FASDs). Prenatal ethanol exposure is associated with persistent dysfunctions of several neurotransmitter systems, including the serotonin (5-HT) system, which plays a major role in mood regulation and stress homeostasis. While PE is known to disrupt the development of the 5-HT system, the cellular mechanisms by which it alters the function of dorsal raphe nucleus (DRn) 5-HT neurons and their synaptic inputs remain unknown. Here, we used a second-trimester binge-drinking pattern PE (two daily gavages of 15% w/v ethanol at 3 g/kg, 5–6 h apart) during gestational days 8 - 20 and measured anxiety-like behaviors of adult male rats using the elevated plus (EPM) and zero (ZM) mazes. We also employed ex-vivo electrophysiological and pharmacological approaches to unravel the mechanisms by which PE alters the excitability and synaptic transmission onto DRn 5-HT neurons. We found that PE enhanced anxiety-like behaviors in adult male rats and induced a persistent activation of DRn 5-HT neurons. The PE-induced activation of DRn 5-HT neurons was largely mediated by potentiation of DRn glutamate synapses, which was caused by activation of the nitrergic system and impaired endocannabinoid signaling. As such, the present study reveals “push-pull” effects of PE on nitrergic and eCB signaling, respectively, which mediate the enhanced activity of DRn 5-HT neurons and could contribute to anxiety-like behaviors observed in animal model of FASD.

Environmental pollution caused by the use of fossil fuels is becoming increasingly serious, necessitating the adoption of clean energy solutions. Lithium-ion batteries (LIBs) have attracted great attention due to their high energy density and currently occupy a dominant commercial position. Metal oxide materials have emerged as promising anode materials for the next generation of LIBs, thanks to their high theoretical capacity. However, the practical application of these materials is hindered by their substantial volume expansion during lithium storage and poor electrical conductivity. In this work, a zinc/iron bimetallic hybrid oxide composite, ZnO/ZnFe2O4/NC, is prepared using ZIF-8 as a precursor (ZIF-8, one of the metal organic frameworks). The N-doped porous carbon composite improves the volume change and optimizes the lithium-ion and electron transport. Meanwhile, the ZnFe2O4 and ZnO synergistically enhance the electrochemical activity of the anode through the built-in heterojunction to promote the reaction kinetics at the interface. As a result, the material delivers an excellent cycling performance of 604.7 mAh g−1 even after 300 cycles of 1000 mA g−1. This study may provide a rational design for the heterostructure and doping engineering of anodes for high-performance lithium-ion batteries.

BackgroundFetal alcohol spectrum disorders (FASD) caused by prenatal ethanol exposure (PE) consist of many cognitive/behavioral deficits. Studies have reported that PE leads to impairments of learning and memory, attention, executive function, and anxiety. Open field (OF) is a common behavioral model which offers comprehensive ethological information. Here, we analyzed multiple parameters of OF to examine anxiety behavior and habituation after PE.Material and MethodsPregnant Sprague Dawley rats were gavaged twice/day with 0 or 3 g/kg/treatment ethanol (15% w/v) during gestational day (GD) 8–20, mimicking second-trimester heavy PE in humans. The control and PE adult offspring were subjected to OF task in different ambient light levels with or without acute stress.ResultsPrenatal ethanol exposure did not influence the overall locomotor activities or habituation in the OF. In lower ambient light, no PE effects could be detected. In higher ambient light, female PE rats showed less activities in the center zone, indicative of increased anxiety. Males show lower activities in the center zone only after acute stress. Rats spent 75% of the time in the corner zone where they engaged in frequent rearing activities (vertical exploration; exploratory rearing). Prenatal ethanol exposure led to lower rearing activities in the corner in both males and females. Acute stress masks the PE effects in males but not in females.DiscussionThe results support that heavy PE leads to persistent anxiety-like behavior during adulthood in both sexes. This conclusion is supported by using multiple parameters of exploratory behavior in the OF, including the rearing activities in the corner to reach reliable quantification of anxiety-like behavior.

Synthetic rutile was prepared from titanium slag melt with a low amount of additive (B2O3) and low energy consumption in our previous work. The mechanism by which B2O3 promotes the precipitation of the rutile phase during the cooling and crystallization of titanium slag melt is not clear and needs further theoretical study. The effects of B2O3 on the structure and properties of titanium slag melt were investigated by molecular dynamics simulations in this study. The B2O3 content has a remarkable effect on the coordination environments of B, Ti and Si atoms, while it has no distinct effect on the position of the central peak in the bond length distributions of BOp, TiOm and SiOn polyhedra. As the B2O3 content increases from 0% to 24%, some of the Ti–O bonds in the oxygen connections are replaced by the B–O bonds and the structural strength of the titanium slag melt is reduced. As the B2O3 content increases from 0% to 24%, the self-diffusion coefficients of all ions increase, and their order remains the same. As the B2O3 content increases from 0% to 24%, the viscosity of the titanium slag melt decreases from 0.079 to 0.032 Pa·s. The addition of B2O3 reduces the overall strength, increases the diffusion coefficients and decreases the viscosity of the titanium slag melt. Such changes are conducive to the oxidation of low-valent titanium and to the precipitation of rutile in titanium slag melt. This work may lay the foundation for the efficient preparation of synthetic rutile by adding B2O3 to the titanium slag melt.

Recent research on the oxygen reduction reaction in has mainly focused on the design and synthesis of non-noble metal catalysts to overcome the cost limitations of precious metals that have a high catalytic activity. The catalytic activity of non-noble metal catalysts has been greatly improved over a large number of studies in the field, but there is still no obvious advantage over precious metal catalysts. In this work, an electrocatalyst with high limiting current density for the oxygen reduction reaction was successfully prepared by codoping a tungsten carbide matrix with Fe and N. The performance of the catalyst was characterized by various physical and electrochemical techniques. The limiting current density in the oxygen reduction reaction (ORR) can reach 6.644 mA cm−2, and the catalyst also has good half-wave and onset potentials. In addition to the excellent stability and methanol tolerance of the cathode process under alkaline conditions, the catalyst also exhibited the four-electron transfer mechanism as well as good ORR kinetics, and the yield of H2O2 was close to 0. This catalyst with its excellent properties is of significance in guiding research on non-noble metal catalysts with comparable performance to traditional noble metal catalysts.

BackgroundNo spatial analysis of hair selenium and Keshan disease (KD) on a nationwide county-level has been performed. Selenium deficiency is a recognized environmental risk factor for KD. Hair selenium is one of the recognized biomarkers of selenium nutrition. This study aimed to perform a geographically precise and visualized assessment of the achievement of KD prevention and control at the level of selenium nutrition in terms of etiology.MethodsA spatial ecological study was conducted. The hair selenium content of the residents was assayed using an atomic fluorescence spectrometer. The spatial analysis was performed using ArcGIS.ResultsThe median of the hair selenium levels of the 3,028 participants in the 1,174 counties was 0.38 mg/kg, and the content of inhabitants in KD endemic counties was significantly lower than that in KD non-endemic counties (0.34 vs. 0.39 mg/kg, z = −10.03, P < 0.0001). The proportion of Se-deficient and Se-marginal counties in KD endemic counties was significantly higher than that in KD non-endemic counties (59.4 vs. 29.0%, z = −7.45, P < 0.0001). The global autocorrelation analysis was not statistically significant (Moran's I = 0.0005, P = 0.68). Local autocorrelation analysis identified 174 low-low clusters of hair selenium levels, 83 (47.7%) of which are KD endemic counties located in KD endemic provinces of Henan, Gansu, Shaanxi, Inner Mongolia, Jilin, and Heilongjiang. The hair selenium featured a positive correlation with per capita GDP (rs = 0.20, P < 0.0001).ConclusionThe median of the hair selenium levels of inhabitants living in KD endemic counties was significantly lower than that in KD non-endemic counties. All the 83 KD endemic counties with low-low clusters of hair selenium levels should be prioritized in KD precision prevention and control. These findings are geographically precise and visualized evidence of the assessment of the effectiveness of KD prevention and control at the level of selenium nutrition in terms of etiology.

Objectives: Few researchers have studied the national prevalence of Keshan disease (KD) in China using spatial epidemiological methods. This study aimed to provide geographically precise and visualized evidence for the strategies for KD prevention and control. Methods: We surveyed and analyzed 237,000 people in 280 out of 328 KD-endemic counties (85.4%) in mainland China using a design of key investigation based on case-searching in 2015–2016. ArcGIS version 9.0 was used for spatial autocorrelation analysis, spatial interpolation analysis and spatial regression analysis. Results: Global autocorrelation analysis showed that global clustering of latent Keshan disease (LKD) prevalence was noted (Moran’s 'I' = 0.22, 'Z' = 7.06, and 'P' < 0.0001), no global clustering of chronic Keshan disease (CKD) prevalence (Moran’s 'I' = 0.03, 'Z' = 1.10, and 'P' = 0.27) was observed. Spatial regression analysis showed that LKD prevalence was negatively correlated with per capita disposable income ('t' = −4.36, 'P' < 0.0001). Local autocorrelation analysis at the county level effectively identified the cluster areas of LKD prevalence in the provinces of Shaanxi, Gansu, Shanxi, Inner Mongolia, and Jilin. The high-high cluster areas should be given priority for precision prevention and control of Keshan disease. Conclusions: This spatial epidemiological study revealed that LKD prevention and control should be strengthened in areas with high values of clustering. Our findings provided spatially, geographically precise and visualized evidence for prioritizing KD prevention and control.

The ammonium tungstate solution obtained by leaching scheelite with phosphate contains a large amount of phosphorus. For production of qualified ammonium paratungstate products, phosphorus must be deeply removed from the ammonium tungstate solution. In this study, a novel process for ammonium phosphate recovery and deep phosphorus removal from the solution was proposed. First, ammonium phosphate was crystallized and separated from the ammonium tungstate solution by blowing ammonia and cooling. Results showed that the crystallization ratio of phosphorus was above 95% under the conditions of an ammonia concentration of 4.18 mol/L, an initial phosphorus concentration ranging from 15 g/L to 30 g/L, a holding time of 60 min and the temperature of 20°C. Then, the small portion of phosphorus remaining in the ammonium tungstate solution was further deeply removed by basic magnesium carbonate percipitation. The phosphorus removal efficiency was above 99% and tungsten loss was less than 0.22% under the following conditions: the basic magnesium carbonate stoichiometric ratio was 1.5, the initial phosphorus concentration was ranging from 0.5 to 4 g/L, the reaction time was 120 min and temperature was 25°C. After phosphorus removal, the concentration of phosphorus in the ammonium tungstate solution was below 10 ppm, which meant deep phosphorus removal was achieved.

In this work, the effect of adding sodium chloride (NaCl) in zinc oxide (ZnO) electron transport layer (ETL) on the photovoltaic performance of lead sulfide (PbS) quantum dot (QD) solar cells is investigated. To elucidate that, PbS QD solar cells with pristine ZnO and NaCl passivated ZnO (ZnO–NaCl) as ETLs are fabricated, respectively. The current density–voltage (J–V)​ measurements are performed. The results show a considerable improvement in the current density of the device with ZnO–NaClas ETL, thus boosting the power conversion efficiency (PCE) from 7.278% to 9.149%. It is demonstrated that NaCl treatment benefits surface defects and series resistance (Rs) reduction in ZnO ETL, enhancing the carrier transport performance of the device. The strategy of adding NaCl in ZnO ETL provides a promising way for pushing solar cell performance to a high level.

Abstract Solution-processed colloidal quantum dot solar cells (CQDSCs) is a promising candidate for new generation solar cells. To obtain stable and high performance lead sulfide (PbS)-based CQDSCs, high carrier mobility and low non-radiative recombination center density in the PbS CQDs active layer are required. In order to effectively improve the carrier mobility in PbS CQDs layer of CQDSCs, butylamine (BTA)-modified graphene oxide (BTA@GO) is first utilized in PbS-PbX2 (X = I−, Br−) CQDs ink to deposit the active layer of CQDSCs through one-step spin-coating method. Such surface treatment of GO dramatically upholds the intrinsic superior hole transfer peculiarity of GO and attenuates the hydrophilicity of GO in order to allow for its good dispersibility in ink solvent. The introduction of BTA@GO in CQDs layer can build up a bulk nano-heterojunction architecture, which provides a smooth charge carrier transport channel in turn improves the carrier mobility and conductivity, extends the carriers lifetime and reduces the trap density of PbS-PbX2 CQDs film. Finally, the BTA@GO/PbS-PbX2 hybrid CQDs film-based relatively large-area (0.35 cm2) CQDSCs shows a champion power conversion efficiency of 11.7% which is increased by 23.1% compared with the control device.

Abstract: La-loaded absorbents have been widely reported for fluoride removal due to the strong affinity of La3+ towards fluoride ion. Herein, chemical removal of fluoride from flue gas scrubbing wastewater using lanthanum salt is investigated. The retaining free F− concentration, phase composition and morphology of filtration residues, and the distribution of fluorine have been investigated using ion-selective electrode, analytical balance, scanning electron microscopy, and X-ray diffractor. The results show that at La/F molar ratio ≥1:3.05, the majority of fluorine exists as LaFx3−x complexes, leading to the failure of fluoride removal. At 1:3.20 ≤ La/F molar ratio ≤1:3.10, the formation of LaF3 is facilitated. However, co-existing LaFx3−x tends to absorb on the surface of LaF3 particles, leading to the formation of colloidal solution with large numbers of LaF3·LaFx3−x suspended solids. At an optimized La/F molar ratio of 1:3.10, a fluoride removal of 97.86% is obtained with retaining fluorine concentration of 6.42 mg L−1. Considering the existing of positively charged LaFx3−x and LaF3·LaFx3−x, coagulation removal of fluoride is proposed and investigated using lanthanum salts and negatively charged SiO2·nH2O colloidal particles, which is in-situ provided via Na2SiO3 hydrolysis at pH near 5.5. At a La/F molar ratio of 1:3.00 and Na2SiO3 dose of 0.50 g L−1, a fluoride removal of 99.25% is obtained with retaining fluorine concentration of 2.24 mg L−1. When Na2SiO3 dose increases to 1.00 g L−1, the retaining fluorine concentration could be further reduced to 0.80 mg L−1.

BackgroundKeshan disease (KD) is strongly associated with selenium deficiency. Selenoprotein P (SELENOP) is a recognized molecular biomarker of selenoproteins and an important indicator of selenium nutrition. This study was aimed at providing geographically precisely visualized evidence of selenium nutrition at molecular level for assessing KD prevention, control, and elimination on the etiological perspective.MethodsWe used spatial ecological design for this study. The serum SELENOP levels of the residents were measured by ELISA. ArcGIS version 9.0 was used for spatial description, spatial autocorrelation analysis of SELENOP levels and spatial regression with per capita disposable income.ResultsThe mean serum SELENOP levels of the 6,382 residents in 1,688 counties were 4.62 ± 1.82 μg/mL. The mean serum SELENOP levels of the residents living in the townships and rural areas of KD endemic counties were not statistically significantly lower than those of the KD non-endemic counties. The mean serum SELENOP levels were globally clustered (Moran's I = 0.03, z = 6.37, and P < 0.0001), and 99.3% (553/557) of the cold spots, identified by local autocorrelation analysis (Getis-Ord-Gi* analysis), were located in the KD endemic provinces of Shaanxi, Shanxi, Henan, Hebei, Shandong, Inner Mongolia, Gansu, Hubei, Chongqing, Yunnan, and Sichuan. The serum SELENOP level was positively correlated with per capita disposable income (t = 3.52, P = 0.0004).ConclusionsThe results of this study were the geographically precisely visualized evidence of selenium nutrition at molecular level for assessing KD elimination on the etiological perspective. The cold spot counties found by Getis-Ord-Gi* analysis in the KD endemic provinces should be the high priority of KD precision prevention and control.

Endocannabinoids (eCBs), which include 2-arachidonoylglycerol (2-AG) and anandamide (AEA) are lipid signaling molecules involved in the regulation of an array of behavioral and physiological functions. Released by postsynaptic neurons, eCBs mediate both phasic and tonic signaling at central synapses. While the roles of phasic eCB signaling in modulating synaptic functions and plasticity are well characterized, very little is known regarding the physiological roles and mechanisms regulating tonic eCB signaling at central synapses. In this study, we show that both 2-AG and AEA are constitutively released in the dorsal raphe nucleus (DRN), where they exert tonic control of glutamatergic synaptic transmission onto serotonin (5-HT) neurons. The magnitude of this tonic eCB signaling is tightly regulated by the overall activity of neuronal network. Thus, short term in vitro neuronal silencing or blockade of excitatory synaptic transmission abolishes tonic eCB signaling in the DRn. Importantly, in addition to controlling basal synaptic transmission, this study reveals that tonic 2-AG, but not AEA signaling, modulates synaptic plasticity. Indeed, short-term increase in tonic 2-AG signaling impairs spike-timing dependent potentiation (tLTP) of glutamate synapses. This tonic 2-AG-mediated homeostatic control of DRN glutamate synapses is not signaled by canonical cannabinoid receptors, but by intracellular peroxisome proliferator-activated receptor gamma (PPARγ). Further examination reveals that 2-AG mediated activation of PPARγ blocks tLTP by inhibiting nitric oxide (NO), soluble guanylate cyclase, and protein kinase G (NO/sGC/PKG) signaling pathway. Collectively, these results unravel novel mechanisms by which tonic 2-AG signaling integrates network activities and controls the synaptic plasticity in the brain.

Rare earth element recovery in molten salt electrolysis is approximately between 91 and 93%, whereof 8% is lost in waste molten salt slag. Presently, minimal research has been conducted on the technology for recycling waste rare earth molten salt slag, which is either discarded as industrial garbage or mixed with waste slag into qualified molten salt. The development of a new approach toward the effective treatment of rare earth fluoride molten salt electrolytic slag, which can recycle the remaining rare earth and improve the utilization rate, is essential. Herein, weak magnetic iron separation, sulfuric acid leaching transformation, water leaching, hydrogen fluoride water absorption, and cycle precipitation of rare earth are used to recover rare earth from their fluoride molten salt electrolytic slag, wherein the thermodynamic and kinetic processes of sulfuric acid leaching transformation are emphatically studied. Thermodynamic results show that temperature has a great influence on sulfuric acid leaching. With rising temperature, the equilibrium constant of the reaction gradually increases, and the stable interval of NdF3 decreases, while that of Nd3+ increases, indicating that high temperature is conducive to the sulfuric acid leaching process, whereof the kinetic results reveal that the activation energy E of Nd transformation is 41.57 kJ/mol, which indicates that the sulfuric acid leaching process is controlled by interfacial chemical reaction. According to the Nd transformation rate equation in the sulfuric acid leaching process of rare earth fluoride molten salt electrolytic slag under different particle size conditions, it is determinable that with the decrease of particle size, the reaction rate increases accordingly, while strengthening the leaching kinetic process. According to the equation of Nd transformation rate in the sulfuric acid leaching process under different sulfuric acid concentration conditions, the reaction series of sulfuric acid concentration K = 6.4, which is greater than 1, indicating that increasing sulfuric acid concentration can change the kinetic-control region and strengthen the kinetic process.

To overcome the problem of arsenic separation and enrichment from an alkaline leaching solution in arsenic-containing dust, a CO32--type tri-n-octylmethyl-ammonium chloride (TOMAC) method for extracting thioarsenite is proposed in this paper. Considering an alkaline leaching solution as the research object, after vulcanization pretreatment, TOMAC transformation and organic phase saturated extraction capacity were measured, and the extraction mechanism was preliminarily studied. First, Cl−-type quaternary ammonium salt was effectively transformed to HCO3--type by treating organic phase with saturated NaHCO3five times. TOMAC was effectively transformed from HCO3- to CO32- type by alkaline washing with 1.0 mol/l NaOH solution; this washing was repeated thrice. Thereafter, the effects of organic phase composition, phase ratio, extraction time, and temperature on the extraction and separation of arsenic were investigated. The results show that under the conditions of 30% CO32--type TOMAC + 15% sec-octanol + 55% sulfonated kerosene, VO/VA = 1/1, and 5 min extraction at room temperature, the single-stage extraction rate of AsIII is 85.2%. The AsIII concentration in raffinate can be reduced to less than 1.33 × 10−3 mol/l by four-stage countercurrent extraction, and the extraction rate of AsIII can exceed 98.4%.

Interpenetrating bulk heterojunction (IBHJ) quantum dot solar cells (QDSCs) offer a direct pathway for electrical contacts to overcome the trade-off between light absorption and carrier extraction. However, their complex three-dimensional structure creates higher requirements for the optimization of their design due to their more difficult interface defect states control, more complex light capture mechanism, and more advanced QD deposition technology. ZnO nanowire (NW) has been widely used as the electron transport layer (ETL) for this structure. Hence, the optimization of the ZnO NW morphology (such as density, length, and surface defects) is the key to improving the photoelectric performance of these SCs. In this study, the morphology control principles of ZnO NW for different synthetic methods are discussed. Furthermore, the effects of the density and length of the NW on the collection of photocarriers and their light capture effects are investigated. It is indicated that the NW spacing determines the transverse collection of electrons, while the length of the NW and the thickness of the SC often affect the longitudinal collection of holes. Finally, the optimization strategies for the geometrical morphology of and defect passivation in ZnO NWs are proposed to improve the efficiency of IBHJ QDSCs.

BackgroundPrenatal ethanol exposure (PE) causes multiple behavioral and cognitive deficits, collectively referred to as fetal alcohol spectrum disorders (FASD). Studies show that 49–94% of FASD children exhibit attention deficits, even when they have normal IQs or lack severe facial deformities, suggesting that attention deficits could be caused by even moderate prenatal exposure to alcohol, of which the underlying neural mechanisms are still unclear. A valid rodent model could help elucidate this phenomenon.Materials and MethodsA second-trimester equivalent binge drinking PE model was utilized. Pregnant Sprague Dawley rats were administered with 15% (w/v) ethanol (6 g/kg/day, via gastric gavage) during gestational days 8–20, and their offspring were the subjects in the present study. A modified 2-choice reaction time (2-CRT) task was used to illustrate possible attention deficits, including increased action impulsivity and lapses of attention. Enhanced impulsivity was reflected by more premature responses while increased lapses of attention were manifested as more incorrect responses and/or greater variability of reaction time, demonstrated by more skewed distributions of reaction time. Ten-week-old male and female rats were tested for three sessions following 16–19 days of training.ResultsOur PE paradigm caused no major teratogenic effects. PE led to increased impulsivity exhibited as greater premature responses and augmented lapses of attention shown by greater skewnesses of reaction time distributions, relative to controls. The deficits were observed in both PE male and female rats. Interestingly, in males, the attention deficits were detected only when the 2-CRT task was relatively difficult whereas in females they were detected even when the task was at a less demanding level.ConclusionWe show that the binge drinking pattern of PE led to attention deficits in both sexes of rats even though no major teratogenic effects were observed. Therefore, this rodent model can be used to study neural mechanisms underlying attention deficits caused by PE and to explore effective intervention approaches for FASD.

Colloidal quantum dot solar cells (CQDSCs) based on one-dimensional metal oxide nanowires (NWs) as the electron transport layer (ETL) have attracted much attention due to their larger ETL/colloidal quantum dots (CQDs) contact area and longer electron transport length than other structure CQDSCs, such as planar CQDSCs. However, it is known that defect states in NWs would increase the recombination rate because of the high surface area of NWs. Here, the defect species on the ZnO NWs' surface which resulted in the surface recombination and SnO2 passivation effects were investigated. Comparing with the solar cells using pristine ZnO NWs, the CQDSCs based on SnO2 passivated ZnO NW electrodes exhibited a beneficial band alignment to charge separation, and the interfacial recombination at the ZnO/CQD interface was reduced, eventually resulting in a 40% improvement of power conversion efficiency (PCE). Overall, these findings indicate that surface passivation and the reduction of deep level defects in ETLs could contribute to improving the PCE of CQDSCs.