Recovery of phosphorus from chemical-enhanced phosphorus removal sludge: Influence of sodium sulfide dosage on phosphorus fractionation, sludge dewaterability, and struvite product.

Despite the potential of sodium sulfide (Na2S) for phosphorus (P) recovery from iron-phosphate waste, the underlying mechanism regarding its impact on P conversion and product quality has not been well addressed. In this study, the effects of Na2S addition on P release and recovery from a chemical-enhanced phosphorus removal (CEPR) sludge during anaerobic fermentation were systematically investigated. The results revealed that the effective mobilization of P bound to Fe (Fe-P) by Na2S dominated the massive P release from the CEPR sludge, while the organic P (OP) release was not significantly enhanced during anaerobic fermentation. Due to the rapid reaction of Na2S with Fe-P and the prevention of Fe(II)-P precipitation by excess S2-, the Fe-P was decreased by 9.7%, 15.2% and 24.9% at S:Fe molar ratios of 0.3, 0.5 and 1, respectively. After anaerobic fermentation, the released P mainly existed as soluble phosphate (SP), P bound to Ca (Ca-P) and P bound to Al (Al-P). The nitrogen and P contents in the fermentation supernatant significantly increased with higher S:Fe ratios, facilitating the efficient recovery of P as high-purity struvite. However, the increased Na2S dosage deteriorated the sludge dewaterability because of the dissolution of hydrophilic extracellular polymeric substances and the looser secondary structure of proteins. Comprehensively considering the P recovery, sludge dewaterability and economic cost, the optimal Na2S dosage was determined at the S:Fe ratio of 0.3. These findings provide novel insights into the role of Na2S in P recovery as struvite from CEPR sludge.

Different Thicknesses of Acellular Porcine Corneal Stroma on Prognosis of Fungal Corneal Ulcers Treated by Lamellar Keratoplasty: A Five-Year Retrospective Study.

PURPOSE: To compare the prognosis and efficacy of acellular porcine corneal stroma (APCS) with different thicknesses for the treatment of fungal corneal ulcers by lamellar keratoplasty (LKP). METHODS: A total of 52 patients who underwent LKP with APCS for the treatment of fungal corneal ulcers were included in this retrospective study. Patients were divided into 2 groups according to the different thicknesses of APCS (0.30 ± 0.05 mm, L2 group, n = 20; 0.40 ± 0.05 mm, L3 group, n = 32). Observation indicators included best corrected visual acuity, graft transparency, corneal neovascularization, ocular irritation symptoms, corneal epithelial healing time, graft survival, central corneal thickness at 1 year after surgery, and postoperative complications. RESULTS: Compared with the L3 group, the L2 group had better postoperative best corrected visual acuity and graft transparency (P < 0.001), less corneal neovascularization (P < 0.001), and lower incidence of complications (P < 0.05). There were significant differences in ocular irritation symptoms between the 2 groups (P < 0.05) at 3 and 6 months postoperatively, which might be related to the higher recurrence rate and graft rejection rate in the L3 group. The comparison of postoperative epithelial healing time also showed significant differences in 2 groups (P < 0.01). The 1-year survival rate was up to 63.5% in both groups, with no significant difference (P < 0.05). However, the risk of transplantation was less in the L2 group. Both APCS thicknesses could provide adequate central corneal thickness at 1 year after surgery (P > 0.05). CONCLUSIONS: APCS was safe and effective in the treatment of fungal corneal ulcers by LKP. Thinner grafts should be preferred for LKP for fungal corneal ulcers to reduce the risk of grafting.

Determination of standard molar volume of 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide on titanium dioxide surface.

The fluids near the solid substrate display different properties compared to the bulk fluids owing to the asymmetric interaction between the fluid and substrate; however, to the best of our knowledge, no work has been conducted to determine the interfacial properties of fluids experimentally. In this work, we combined a pycnometer with experimental measurements and data processing to determine the standard thermodynamic properties of interfacial fluids for the first time. In the study, 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Hmim][NTf2]) and titanium dioxide (P25) were chosen as the probes to prove the concept. It was found that, with the combination of the Gay-Lussac pycnometer and the colligative law, together with selecting a suitable solvent, it is possible and reliable to determine the standard molar volume of the immobilized [Hmim][NTf2]. Compared to the bulk phase, the molar volumes of [Hmim][NTf2] on the P25 surface reduce by 20.8%-23.7% at temperatures from 293.15 to 323.15 K, and the reduction degrees decrease with increasing temperatures. The newly determined standard thermodynamic data was used to obtain the model parameters of hybrid electrolyte perturbed-chain statistical associating fluid theory density functional theory (ePC-SAFT-DFT), and further predictions of the density of interfacial ionic liquids with different film thicknesses were proved to be reliable in comparison with the experiment results.

Enhancing Adhesion and Reducing Ohmic Contact through Nickel-Silicon Alloy Seed Layer in Electroplating Ni/Cu/Ag.

Due to the lower cost compared to screen-printed silver contacts, the Ni/Cu/Ag contacts formed by plating have been continuously studied as a potential metallization technology for solar cells. To address the adhesion issue of backside grid lines in electroplated n-Tunnel Oxide Passivating Contacts (n-TOPCon) solar cells and reduce ohmic contact, we propose a novel approach of adding a Ni/Si alloy seed layer between the Ni and Si layers. The metal nickel layer is deposited on the backside of the solar cells using electron beam evaporation, and excess nickel is removed by H2SO4:H2O2 etchant under annealing conditions of 300-425 °C to form a seed layer. The adhesion strength increased by more than 0.5 N mm-1 and the contact resistance dropped by 0.5 mΩ cm2 in comparison to the traditional direct plating Ni/Cu/Ag method. This is because the resulting Ni/Si alloy has outstanding electrical conductivity, and the produced Ni/Si alloy has higher adhesion over direct contact between the nickel-silicon interface, as well as enhanced surface roughness. The results showed that at an annealing temperature of 375 °C, the main compound formed was NiSi, with a contact resistance of 1 mΩ cm-2 and a maximum gate line adhesion of 2.7 N mm-1. This method proposes a new technical solution for cost reduction and efficiency improvement of n-TOPCon solar cells.

Epidemiological Characteristics of Overseas-Imported Infectious Diseases Identified through Airport Health-Screening Measures: A Case Study on Fuzhou, China.

BACKGROUND: This study aimed to examine the epidemiological characteristics of imported infections and assess the effectiveness of border health screening in detecting imported diseases. METHODS: We obtained infection data for 2016 to 2019 from the Fuzhou Changle International Airport Infection Reporting System. The demographic, temporal, and spatial characteristics of travel-related infections were analyzed using r×c contingency tables, the Cochran-Armitage trend test, and seasonal-trend decomposition using LOESS (STL). Detection rates were used as a proxy for the effectiveness of border health-screening measures. RESULTS: Overall, 559 travel-related infections were identified during the study period, with 94.3% being imported infections. Airport health screening demonstrated an overall effectiveness of 23.7% in identifying travel-associated infections. Imported infections were predominantly identified in males, with 55.8% of cases occurring in individuals aged 20-49. The peak periods of infection importation were from January to February and from May to August. The infectious diseases identified were imported from 25 different countries and regions. All dengue fever cases were imported from Southeast Asia. Most notifiable infections (76.0%) were identified through fever screening at the airport. CONCLUSION: The increasing number of imported infections poses a growing challenge for public health systems. Multifaceted efforts including surveillance, vaccination, international collaboration, and public awareness are required to mitigate the importation and spread of infectious diseases from overseas sources.

Heat-resistant boron-nitrogen doped lignin-derived adsorbent-catalyst for gaseous aromatic pollutants removal.

Lignin-based carbon material can be utilized as carbonaceous adsorbents for the removal of toxic gaseous organic pollutants, while the poor heat-resistance limited its widely application. Here in, B-N co-doped lignin carbon (BN-C) with high thermal stability was synthesized, and the optimized BN-C (1:2) exhibited notably improved heat resistance with the decomposition temperature up to 505 °C, and excellent adsorption capacity for o-dichlorobenzene (o-DCB) (1510.0 mg/g) and toluene (947.3 mg/g), together with good cyclic stability over 10 cycles for o-dichlorobenzene. The existence of abundant hexagonal boron nitride (h-BN) with good thermal conductivity contributed to the superior heat-resistance of BN-C (1:2), and the high specific surface area (1764.5 m2/g), enriched hydroxyl functional groups and improved graphitization degree contributed to its enhanced adsorption performance. More importantly, BN-C (1:2) supported Ru could effectively remove o-DCB and toluene at wide temperature range (50-300 °C). The present work guided the development of heat-resistant lignin-derived adsorbent-catalyst for gaseous aromatic pollutants removal, which benefits both environmental protection and resource utilization.

A coupling strategy combined with acid-hydrothermal and novel DES pretreatment: Enhancing biomethane yield under solid-state anaerobic digestion and efficiently producing xylo-oligosaccharides and recovered lignin from poplar waste.

Lignocellulose is an abundant renewable bio-macromolecular complex, which can be used to produce biomethane and other high-value products. The lignin, presents in lignocellulose is typically regarded as an inhibitor of anaerobic digestion. Therefore, it is crucial to develop a novel selective separation strategy to achieve efficient biomethane production and all-component utilization of biomass. Hence, a combination of two-step pretreatment and solid-state anaerobic digestion was employed to enhance the production of biomethane and to generate valuable chemicals from poplar waste. Optimal conditions (4 % acetic acid, 170 °C, and 40 min) resulted in 70.85 % xylan removal, yielding 50.28 % xylo-oligosaccharides. The effect of a strong acid 4-CSA-based novel three-constituent DES on delignification was investigated from 80 °C to 100 °C; the cellulose content of DES pretreated poplar increased from 64.11 % to 80.92 %, and the delignification rate increased from 49.0 % to 90.4 %. However, high delignification of the pretreated poplar (DES-100 and DES-110) led to a rapid accumulation of volatile organic acids during the hydrolysis and acidogenesis stages, resulting in methanogenesis inhibition. The highest biomethane yield of 208 L/kg VS was achieved with DES-80 (49.0 % delignification), representing a 148 % improvement compared over untreated poplar. This approach demonstrates the potential for comprehensive utilization of all components of biomass waste.

Atomically Resolved Defect-Engineering Scattering Potential in 2D Semiconductors.

Engineering atomic-scale defects has become an important strategy for the future application of transition metal dichalcogenide (TMD) materials in next-generation electronic technologies. Thus, providing an atomic understanding of the electron-defect interactions and supporting defect engineering development to improve carrier transport is crucial to future TMDs technologies. In this work, we utilize low-temperature scanning tunneling microscopy/spectroscopy (LT-STM/S) to elicit how distinct types of defects bring forth scattering potential engineering based on intervalley quantum quasiparticle interference (QPI) in TMDs. Furthermore, quantifying the energy-dependent phase variation of the QPI standing wave reveals the detailed electron-defect interaction between the substitution-induced scattering potential and the carrier transport mechanism. By exploring the intrinsic electronic behavior of atomic-level defects to further understand how defects affect carrier transport in low-dimensional semiconductors, we offer potential technological applications that may contribute to the future expansion of TMDs.

Palladium-Catalyzed Enantioselective Multicomponent Cross-Coupling of Trisubstituted Olefins.

The development of a catalytic method for stereogenic carbon center formation holds immense significance in organic synthesis. Transition-metal-catalyzed cross-coupling reaction has been regarded as a straightforward and efficient tool for stereoselectively forging C-C bond. Nevertheless, the creation of acyclic all-carbon quaternary-containing vicinal stereocenters remains notoriously challenging within the domain of cross-coupling chemistry despite their prominence in various bioactive small molecules. Herein, we describe a palladium-catalyzed asymmetric multicomponent cross-coupling of trisubstituted alkene with aryl diazonium salts and arylboronic acids to realize the formation of tertiary-quaternary carbon centers with high regio-, distereo-, and enantioselectivity. Specifically, the precise manipulation of the stereoconfiguration of trisubstituted alkenes enables the divergent stereoselective cross-coupling reaction, thus allowing for the facile construction of all four enantiomers. Harnessing the ligand-swap strategy involving a chiral bisoxazoline and an achiral fumarate individually accelerates the enantioselective migratory insertion and reductive elimination step in the cross-coupling process, as supported by density functional theory (DFT) calculations, thus obviating the requirement for a neighboring directing group within the internal olefin skeleton.

Solvent engineering for scalable fabrication of perovskite/silicon tandem solar cells in air.

Perovskite/silicon tandem solar cells hold great promise for realizing high power conversion efficiency at low cost. However, achieving scalable fabrication of wide-bandgap perovskite (~1.68 eV) in air, without the protective environment of an inert atmosphere, remains challenging due to moisture-induced degradation of perovskite films. Herein, this study reveals that the extent of moisture interference is significantly influenced by the properties of solvent. We further demonstrate that n-Butanol (nBA), with its low polarity and moderate volatilization rate, not only mitigates the detrimental effects of moisture in air during scalable fabrication but also enhances the uniformity of perovskite films. This approach enables us to achieve an impressive efficiency of 29.4% (certified 28.7%) for double-sided textured perovskite/silicon tandem cells featuring large-size pyramids (2-3 µm) and 26.3% over an aperture area of 16 cm2. This advance provides a route for large-scale production of perovskite/silicon tandem solar cells, marking a significant stride toward their commercial viability.

Enhanced CO2 Capture through SAPO-34 Impregnated with Ionic Liquid.

The concurrent utilization of an adsorbent and absorbent for carbon dioxide (CO2) adsorption with synergistic effects presents a promising technique for CO2 capture. Here, 1-butyl-3-methylimidazole acetate ([Bmim][Ac]), with a high affinity for CO2, and the molecular sieve SAPO-34 were selected. The impregnation method was used to composite the hybrid samples of [Bmim][Ac]/SAPO-34, and the pore structure and surface property of prepared samples were characterized. The quantity and kinetics of the sorbed CO2 for loaded samples were measured using thermogravimetric analysis. The study revealed that SAPO-34 could retain its pristine structure after [Bmim][Ac] loading. The CO2 uptake of the loaded sample was 1.879 mmol g-1 at 303 K and 1 bar, exhibiting a 20.6% rise compared to that of the pristine SAPO-34 recording 1.558 mmol g-1. The CO2 uptake kinetics of the loaded samples were also accelerated, and the apparent mass transfer resistance for CO2 sorption was significantly reduced by 11.2% compared with that of the pure [Bmim][Ac]. The differential scanning calorimetry method revealed that the loaded sample had a lower CO2 desorption heat than that of the pure [Bmim][Ac], and the CO2 desorption heat of the loaded samples was between 30.6 and 40.8 kJ mol-1. The samples exhibited good cyclic stability. This material displays great potential for CO2 capture applications, facilitating the reduction of greenhouse gas emissions.

Nickel-catalyzed acylation of vinylpyridine with alkylzincs under 1 atm CO.

A nickel-catalyzed acylation of vinylpyridines with CO at atmospheric pressure is reported, allowing for an expedient approach to synthesize ß-acyl pyridine derivatives with high regio- and chemoselectivity. The electron-withdrawing property of pyridine plays pivotal roles in activating the alkenyl group, thereby facilitating this carbonylative process. In addition to vinylpyridines, other alkenylheterocycles such as thiazole and quinoline were also suitable for this method.

Within-Session Reliability of fNIRS in Robot-Assisted Upper-Limb Training.

Functional near-infrared spectroscopy (fNIRS) seems opportune for neurofeedback in robot-assisted rehabilitation training due to its noninvasive, less physical restriction, and no electromagnetic disturbance. Previous research has proved the cross-session reliability of fNIRS responses to non-motor tasks (e.g., visual stimuli) and fine-motor tasks (e.g., finger tapping). However, it is still unknown whether fNIRS responses remain reliable 1) in gross-motor tasks, 2) within a training session, and 3) for different training parameters. Hence, this study aimed to investigate the within-session reliability of fNIRS responses to gross-motor tasks for different training parameters. Ten healthy participants were recruited to conduct right elbow extension-flexion in three robot-assisted modes. The Passive mode was fully motor-actuated, while Active1 and Active2 modes involved active engagement with different resistance levels. FNIRS data of three identical runs were used to assess the within-session reliability in terms of the map- ( R2 ) and cluster-wise ( Roverlap ) spatial reproducibility and the intraclass correlation (ICC) of temporal features. The results revealed good spatial reliability ( R2 up to 0.69, Roverlap up to 0.68) at the subject level. Besides, the within-session temporal reliabilities of Slope, Max/Min, and Mean were between good and excellent ( ICC < 0.86). We also found that the within-session reliability was positively correlated with the intensity of the training mode, except for the temporal reliability of HbO in Active2 mode. Overall, our results demonstrated good within-session reliability of fNIRS responses, suggesting fNIRS as reliable neurofeedback for constructing closed-loop robot-assisted rehabilitation systems.

Nickel-Catalyzed Carbonylative Negishi Cross-Coupling of Unactivated Secondary Alkyl Electrophiles with 1 atm CO Gas.

We describe a nickel-catalyzed carbonylative cross-coupling of unactivated secondary alkyl electrophiles with the organozinc reagent at atmospheric CO gas, thus allowing the expedient construction of unsymmetric dialkyl ketones with broad functional group tolerance. The leverage of a newly developed NN2-pincer type ligand enables the chemoselective three-component carbonylation by overcoming the competing Negishi coupling, the undesired ß-hydride elimination, and dehalogenation of alkyl iodides side pathways. Both alkyl iodides and alkyl tosylates are compatible in the single electron transfer involved mechanism.

Poly(Glutamic Acid-Lysine) Hydrogels with Alternating Sequence Resist the Foreign Body Response in Rodents and Non-Human Primates.

The foreign body response (FBR) to implanted biomaterials and biomedical devices can severely impede their functionality and even lead to failure. The discovery of effective anti-FBR materials remains a formidable challenge. Inspire by the enrichment of glutamic acid (E) and lysine (K) residues on human protein surfaces, a class of zwitterionic polypeptide (ZIP) hydrogels with alternating E and K sequences to mitigate the FBR is prepared. When subcutaneously implanted, the ZIP hydrogels caused minimal inflammation after 2 weeks and no obvious collagen capsulation after 6 months in mice. Importantly, these hydrogels effectively resisted the FBR in non-human primate models for at least 2 months. In addition, the enzymatic degradability of the gel can be controlled by adjusting the crosslinking degree or the optical isomerism of amino acid monomers. The long-term FBR resistance and controlled degradability of ZIP hydrogels open up new possibilities for a broad range of biomedical applications.

Comprehensive Mechanistic Analysis of Palladium- and Nickel-Catalyzed α,ß-Dehydrogenation of Carbonyls via Organozinc Intermediates.

Introducing degrees of unsaturation into small molecules is a central transformation in organic synthesis. A strategically useful category of this reaction type is the conversion of alkanes into alkenes for substrates with an adjacent electron-withdrawing group. An efficient strategy for this conversion has been deprotonation to form a stabilized organozinc intermediate that can be subjected to α,ß-dehydrogenation through palladium or nickel catalysis. This general reactivity blueprint presents a window to uncover and understand the reactivity of Pd- and Ni-enolates. Within this context, it was determined that ß-hydride elimination is slow and proceeds via concerted syn-elimination. One interesting finding is that ß-hydride elimination can be preferred to a greater extent than C-C bond formation for Ni, more so than with Pd, which defies the generally assumed trends that ß-hydride elimination is more facile with Pd than Ni. The discussion of these findings is informed by KIE experiments, DFT calculations, stoichiometric reactions, and rate studies. Additionally, this report details an in-depth analysis of a methodological manifold for practical dehydrogenation and should enable its application to challenges in organic synthesis.

Buoyancy-Driven Dissolution Instability in a Horizontal Hele-Shaw Cell.

The dissolution of minerals within rock fractures is fundamental to many geological processes. Previous research on fracture dissolution has highlighted the significant role of buoyancy-driven convection leading to dissolution instability. Yet, the pore-scale mechanisms underlying this instability are poorly understood primarily due to the challenges in experimentally determining flow velocity and concentration fields. Here, we integrate pore-scale simulations with theoretical analysis to delve into the dissolution instability prompted by buoyancy-driven convection in a radial horizontal geometry. Initially, we develop a pore-scale modeling approach incorporating gravitational effects, subsequently validating it through experiments. We then employ pore-scale numerical simulations to elucidate the 3D intricacies of flow-dissolution dynamics. Our findings reveal that a simple criterion can delineate the condition for the onset of buoyancy-driven dissolution instability. If the characteristic length falls below a critical threshold, dissolution remains stable. Conversely, exceeding this threshold leads to two distinct regimes: the unstable regime of the confined domain affected by the initial aperture and the unstable regime of the semi-infinite domain independent of the initial aperture where the instability is no longer influenced by the lower boundary. We demonstrate that the pore-scale mechanism for this instability is due to the concentration boundary layer attaining a gravitationally unstable critical thickness. Through theoretical analysis of this layer and the time scales of diffusion and advection, we establish a theoretical model to predict where the dissolution instability occurs. This model aligns closely with our numerical simulations and experimental data across diverse conditions. Our work improves the understanding of buoyancy-driven dissolution instability in radial horizontal geometry. It is also of practical significance in understanding cavity formation in karst hydrology and preventing leaks in geological CO2 storage.

Effect of PLGF and EZH2 Expression in Placenta Tissue on GDM Placental Structure and Pregnancy Outcome.

Objective: To explore the relationship between the expression of placental growth factor (PLGF) and Zeste homolog enhancer 2 (EZH2) in placental tissues of women with gestational diabetes (GDM), placental function, and pregnancy outcome. Methods: Select 100 women with GDM diagnosed in our hospital from January 2019 to May 2020 as the GDM group and 100 women with normal pregnancy at the same time as the control group. Detection and analysis of the expression levels of PLGF and EZH2 proteins in placental tissue after delivery of the two components. Observation of the expression of different PLGF and EZH2 proteins using an electron microscope, and analyze the ultrastructural changes in placental tissue of women with GDM. Finally, assess the differences in pregnancy outcomes. Results: The expression intensity of PLGF protein in the GDM group was higher than that in the control group (P < .001), and the expression intensity of EZH2 protein in the GDM group was lower than that in the control group (P < .001); the positive rate of PLGF protein in the GDM group was 67.00% higher than that of the control group 35.00% (P < .001), the positive rate of EZH2 protein in the GDM group was 15.00% lower than 33.00% in the control group (P = .003); the placental ultrastructural change rate of PLGF-positive GDM women was 71.64% higher than that in the negative expression group 45.45 % (P = .011); the placental ultrastructural change rate of EZH2 protein-positive GDM mothers was 33.33% lower than that of negative expression of A mixed 68.24% (P = .01); the incidence of premature infants (26.87%) and fetal respiratory distress (13.43%) in the PLGF-positive GDM group, the rate was higher than that in the negative expression group (9.09%, 0%) (P = .027, .04); the incidence of preterm infants in the EZH2 protein-positive GDM group (0.00%) was lower than that in the negative expression group (24.71%) (P = .03). Conclusion: The expression of PLGF is up-regulated and the expression of EZH2 is down-regulated in the placental tissue of GDM women, which causes ultrastructural changes in the placental tissue and increases the incidence of preterm birth and fetal respiratory distress to a certain extent.

Cobalt-Catalyzed Enantioselective Reductive α-Chloro-Carbonyl Addition of Ketimine to Construct the ß-Tertiary Amino Acid Analogues.

ß-Tertiary amino acid derivatives constitute one of the most frequently occurring units in natural products and bioactive molecules. However, the efficient asymmetric synthesis of this motif still remains a significant challenge. Herein, we disclose a cobalt-catalyzed enantioselective reductive addition reaction of ketimine using α-chloro carbonyl compound as a radical precursor, providing expedient access to a diverse array of enantioenriched ß-quaternary amino acid analogues. This protocol exhibits outstanding enantioselectivity and broad substrate scope with excellent functional group tolerance. Preliminary mechanism studies rule out the possibility of Reformatsky-type addition and confirm the involvement of radical species in stereoselective addition process. The synthetic utility has been demonstrated through the rapid assembly of iterative amino acid units and oligopeptide, showcasing its versatile platform for late-stage modification of drug candidates.