Polyvinyl Pyrrolidone Induced "Confinement Effect" on PbI2 and the Improvement on Crystallization and Thermal Stability of Perovskite.

Polyvinyl pyrrolidone is blended in PbI2 with varied concentration, so as to study the coarsening dynamics of perovskite during the two-step growth method. It is observed that polyvinyl pyrrolidone hinders the crystallization of PbI2 and helps to form a more amorphous PbI2 matrix, which then improves perovskite crystallization. As the blending concentration increases from 0 to 2 mM, average crystallite/grain size of perovskite increases from 40.29 nm/0.79 µm to 84.35 nm/1.02 µm while surface fluctuation decreases slightly from 25.64 to 23.96 nm. The observations are caused by the "confinement effect" brought by polyvinyl pyrrolidone on PbI2 . Elevating blending concentration of polyvinyl pyrrolidone results in smaller PbI2 crystallites and more amorphous PbI2 matrix, thus reducing the diffusion/reaction barrier between PbI2 and organic salt and favoring perovskite crystallization. As blending concentration increases from 0 to 2 mM, the device efficiency rises from 19.76 (± 0.60) % to 20.50 (± 0.89) %, with the optimized value up to 22.05%, which is further improved to 24.48% after n-Octylammonium iodide (OAI)-basing surface modification. The study enlarges the scope of "confinement effect" brought by polymer molecules, which is beneficial for efficient and stable perovskite solar cell fabrication.

Improved Thermal Stability and Film Uniformity of Halide Perovskite by Confinement Effect brought by Polymer Chains of Polyvinyl Pyrrolidone.

Polyvinyl pyrrolidone (PVP) is doped to PbI2 and organic salt during two-step growth of halideperovskite. It is observed that PVP molecules can interact with both PbI2 and organic salt, reduce the aggregation and crystallization of the two, and then slow down the coarsening rate of perovskite. As doping concentration increases from 0 to 1 mM in organic salt, average crystallite size of perovskite decreases monotonously from 90 to 34 nm; Surface fluctuation reduces from 259.9 to 179.8 nm at first, and then increases; Similarly, surface roughness decreases from 45.55 to 26.64 nm at first, and then rises. Accordingly, a kind of "confinement effect" is resolved to crystallite growth and surface fluctuation/roughness, which helps to build compact and uniform perovskite film. Density of trap states (t-DOS) is cut down by ≈60% at moderate doping  (0.2 mM). Due to the "confinement effect", power conversion efficiency of perovskite solar cells is improved from 19.46 (±2.80) % to 21.50 (±0.99) %, and further improved to 24.11% after surface modification. Meanwhile, "confinement effect" strengthens crystallite/grain boundaries and improves thermal stability of both film and device. T80 of device increases to 120 h, compared to 50 h for reference ones.

An Intelligent Cost-Reference Particle Filter with Resampling of Multi-Population Cooperation.

Although the cost-reference particle filter (CRPF) has a good advantage in solving the state estimation problem with unknown noise statistical characteristics, its estimation accuracy is still affected by the lack of particle diversity and sensitivity to the particles' initial value. In order to solve these problems of the CRPF, this paper proposed an intelligent cost-reference particle filter algorithm based on multi-population cooperation. A multi-population cooperative resampling strategy based on ring structure was designed. The particles were divided into multiple independent populations upon initialization, and each population generated particles with a different initial distribution. The particles in each population were divided into three different particle sets with high, medium and low weights by the golden section ratio according to the weight. The particle sets with high and medium weights were retained. Then, a cooperative strategy based on Gaussian mutation was designed to resample the low-weight particle set of each population. The high-weight particles of the previous population in the ring structure were randomly selected for Gaussian mutation to replace the low-weight particles in the current population. The low-weight particles of all populations were resampled in turn. The simulation results show that the intelligent CRPF based on multi-population cooperation proposed in this paper can reduce the sensitivity of the CRPF to the particles' initial value and improve the particle diversity in resampling. Compared with the general CRPF and intelligent CRPF with adaptive MH resampling (MH-CRPF), the RMSE and MAE of the proposed method are lower.

Improved Crystallization of Lead Halide Perovskite in Two-Step Growth Method by Polymer-Assisted "Slow-Release Effect".

Fast reaction between organic salt and lead iodide always leads to small perovskite crystallites and concentrated defects. Here, polyacrylic acid is blended with organic salt, so as to regulate the crystallization in a two-step growth method. It is observed that addition of polyacrylic acid retards aggregation and crystallization behavior of the organic salt, and slows down the reaction rate between organic salt and PbI2 , by which "slow-release effect" is defined. Such effect improves crystallization of perovskite. X-ray diffraction study shows that, after addition of 2 mm polyacrylic acid, average crystallite size of perovskite increases from ≈40 to ≈90 nm, meanwhile, grain size increases. Thermal admittance spectroscopy study shows that trap density is reduced by nearly one order (especially for deep energy levels). Due to the improved crystallization and reduced trap density, charge recombination is obviously reduced, while lifetime of charge carriers in perovskite film and devices are prolonged, according to time-resolved photoluminescence and transient photo-voltage decay curve tests, respectively. Accordingly, power conversion efficiency of the device is promoted from 19.96 (±0.41)% to 21.84 (±0.25)% (with a champion efficiency of 22.31%), and further elevated to 24.19% after surface modification by octylammonium iodide.

Consolidation of hydrogenotrophic methanogenesis by sulfidated nanoscale zero-valent iron in the anaerobic digestion of food waste upon ammonia stress.

The feasibility of adding sulfidated nanoscale zero-valent iron (S-nZVI) into anaerobic systems to improve anaerobic digestion of food waste (FW) under ammonia stress was evaluated in this study. The addition of S-nZVI improved the methane production compared to nanoscale zero-valent iron (nZVI), indicating that sulfidation significantly reinforced the enhancement effect of nZVI in consolidating the hydrogenotrophic methanogenesis. The promoted methanogenic performance was associated with chemical reaction and variances of microbial community induced by S-nZVI. With the characteristics of generation of Fe2+ and slow-release of H2, S-nZVI made the anaerobic system respond positively in facilitating extracellular polymeric substances secretion and optimizing the microbial community structure. Moreover, microbial community analysis showed that S-nZVI addition enriched the species related to biohydrogen production (e.g., Prevotella) and ammonia-tolerant hydrogenotrophic methanogenesis (e.g., Methanoculleus), possibly enhancing the hydrogenotrophic methanogenesis pathway to accelerate methane production. Therefore, adding S-nZVI into the anaerobic systems might propose a feasible engineering strategy to improve the methanogenic performance of the anaerobic digestion of FW upon ammonia stress.

A collaborative strategy for enhanced anaerobic co-digestion of food waste and waste activated sludge by using zero valent iron and ferrous sulfide.

The application of sulfidated zero-valent iron as an alternative used in coupled anaerobic systems to improve methane production is usually restricted by its high production costs and toxic gasses and wastewater generation. In this study, a collaborative strategy for coupling zero-valent iron (ZVI) and ferrous sulfide (FeS) together into anaerobic systems was used to evaluate the enhancement of methanogenesis during the co-digestion of food waste and waste activated sludge, with the microbial evolution and metabolic pathway revealed. Results showed that the enhanced hydrolysis and acidogenesis process of co-digestion in this coupled anaerobic system could be attributed to synergistic interactions among ZVI, FeS, and microorganisms. Furthermore, both acetoclastic and hydrogenotrophic pathways could be promoted by coupling ZVI and FeS. This study demonstrated that coupling ZVI and FeS together into anaerobic systems would be a promising method for improving the methanogenic performance for municipal solid waste treatment.

Concentration Prediction of Polymer Insulation Aging Indicator-Alcohols in Oil Based on Genetic Algorithm-Optimized Support Vector Machines.

The predictive model of aging indicator based on intelligent algorithms has become an auxiliary method for the aging condition of transformer polymer insulation. However, most of the current research on the concentration prediction of aging products focuses on dissolved gases in oil, and the concentration prediction of alcohols in oil is ignored. As new types of aging indicators, alcohols (methanol, ethanol) are becoming prevalent in the aging evaluation of transformer polymer insulation. To address this, this study proposes a prediction model for the concentration of alcohols based on a genetic-algorithm-optimized support vector machine (GA-SVM). Firstly, accelerated thermal aging experiments on oil-paper insulation are conducted, and the concentration of alcohols is measured. Then, the data of the past 4 days of aging are used as the input feature of SVM, and the GA algorithm is utilized to optimize the kernel function parameter and penalty factor of SVM. Moreover, the concentrations of methanol and ethanol are predicted, after which the prediction accuracy of other algorithms and GA-SVM are compared. Finally, an industrial software program for predicting the concentration of methanol and ethanol is established. The results show that the mean square errors (MSE) of methanol and ethanol concentration predictions of the model proposed in this paper are 0.008 and 0.003, respectively. The prediction model proposed in this paper can track changes in methanol and ethanol concentrations well, providing a theoretical basis for the field of alcohol concentration prediction in transformer oil.

Rapid initiation of methanogenesis in the anaerobic digestion of food waste by acclimatizing sludge with sulfidated nanoscale zerovalent iron.

Although coupling of sulfidated nanoscale zero-valent iron (S-nZVI) into anaerobic digestion of food waste (FW) for improving methanogenesis has been reported, the specific role of S-nZVI during start-up process and its influence on subsequent methanogenesis and system stability remains unknown. In this study, S-nZVI was added into the unacclimatized sludge system to investigate its influence on microbial acclimatization and methanogenic performance. During acclimatization phase, CH4 production improved and VFAs transformation facilitated with the addition of S-nZVI. Furthermore, enzymatic activity analysis and electrochemical measurements presented direct evidence that electron transfer capacity of acclimatized sludge was significantly improved. S-nZVI favored the transition of microbial community to a robust and specialized population. During evaluation phase, acclimatized sludge still exhibited strong methanogenic ability, but the microbial community inevitably changed under the stress of FW. This research provides a novel perspective on initiating anaerobic digestion of FW for shorter start-up time and stronger methanogenesis.

Case Report: SMARCB1 (INI-1)-Deficient Carcinoma of the Nasal Cavity with Pure Yolk Sac Tumor Differentiation and Elevated Serum AFP Levels.

In adults, yolk sac tumors (YSTs) in the nasal cavity and paranasal sinuses are very rare. To date, only six cases have been reported in the English literature. YSTs in adults are often accompanied by cancer, teratocarcinosarcoma, and other malignant components. Here, we have reported a case of nasal tumor in a 55-year-old man with nasal obstruction and epistaxis. Morphologically, the tumor showed histological characteristics of pure YST. Immunohistochemical staining showed diffuse expression of SALL4, CDX2, and GPC-3 accompanied by sporadic expression of alpha-fetoprotein (AFP) and CD117. After 20 and 40 days of operation, the serum AFP level was 220.30 and 43.60 ng/mL (normal, <7 ng/mL), respectively, which supported the pathological diagnosis of YST. However, we further performed immunohistochemical staining and fluorescence in situ hybridization using an INI-1 probe to detect the status of INI-1 in tumor cells. The results revealed that INI-1 was absent in tumor cells. Hence, we corrected the diagnosis to SMARCB1 (INI-1)-deficient carcinoma of the nasal cavity with YST differentiation. The patient underwent surgery and adjuvant radiotherapy in our hospital without evidence of recurrence or metastasis at the 6-month follow-up. The serum AFP level had also normalized. In conclusion, our case demonstrates that INI-1-deficient carcinoma may exhibit, a pure YST differentiation and immunophenotype, and elevated serum AFP levels. In adults, YST in the nasal cavity may represent INI-1-deficient carcinoma, which may be a potential diagnostic pitfall.

CRISPR/Cas12a-Based Versatile Method for Checking Quantitative Polymerase Chain Reaction Samples with Cycles of Threshold Values in the Gray Zone.

Quantitative polymerase chain reaction (qPCR) is widely applied in foodborne pathogen detection and diagnosis. According to the cycles of threshold (Ct) values of qPCR testing, samples are judged as positive or negative. However, samples with Ct values in the gray zone are classified as "possibly positive" and required to be tested again. Repetitive qPCR may not eliminate the uncertain results but increase the workload of detection. CRISPR/Cas12a can specifically recognize the nucleic acid of the nM level and then indiscriminately slash the single-strand DNA with multiple turnovers. In this way, the detection signals can be greatly amplified. Here, we propose a CRISPR-based checking method to solve gray zone problems. After qPCR testing, the screening gray zone samples can be successfully checked by the CRISPR/Cas12a method. Furthermore, to conduct CRISPR reaction assay more conveniently and prevent possible aerosol contamination in the operational process, a gray zone checking cassette is designed. African swine fever virus (ASFV) is selected as an example to demonstrate the feasibility of the CRISPR-based checking method. Of 28 real swine blood samples, 6 ASFV qPCR gray zone samples are successfully checked. The CRISPR-based checking method provides a novel solution to eliminate gray zone sample problems with no additional effects on the PCR, which is operable and applicable in practical detection. The entire process can be completed within 10-15 min. This method will be a good supplementary and assistance for qPCR-based detection, especially in the diagnosis of diseases such as COVID-19.

Fe2P-decorated N,P Codoped Carbon Synthesized via Direct Biological Recycling for Endurable Sulfur Encapsulation.

In spite of the great potential in leading next-generation energy storage technology, Li-S batteries suffer rapid capacity decay arising from the shuttling effect of lithium polysulfides (LiPSs), a major concern that must be addressed before commercialization can be realized. To tackle this challenge, we demonstrate a facile approach to fabricate a hierarchically structured composite of Fe2P@nitrogen, phosphorus codoped carbon (Fe2P@NPC) by direct biological recycling of iron metal from electroplating sludge using bacteria. This material, featuring uniform dispersion of Fe2P nanoparticles (NPs) in porous NPC matrix, effectively adapts volume variation of sulfur upon cycling and simultaneously provides multiple channels for efficient lithium ion transport. In addition, Fe2P NPs with strong adhesion properties of tightly anchored soluble LiPSs formed during discharge can significantly facilitate the decomposition of Li2S during the subsequent charging process. The Li-S cell built on this cathode architecture delivers high specific capacity (1555.7 mAh g-1 at 0.1 C), appreciable rate capability (679.7 mAh g-1 at 10 C), and greatly enhanced cycling performance (761.9 mAh g-1 at 1.0 C after 500 cycles).

Synthesis, structure and photocatalytic property of a novel Zn(II) coordination polymer based on in situ synthetized pyridine-3,4-dicarboxylhydrazidate ligand.

One new pyridine-3,4-dicarboxylhydrazidate-coordinated compound [Zn(pdh)] 1 (pdh = pyridine-3,4-dicarboxylhydrazidate) was obtained under the hydrothermal conditions. Noteworthily, the pdh molecules in the title compound originated from the ligand in situ reaction between organic pyridine-3,4-dicarboxylic acid (pdca) and N2H4·H2O. X-ray single-crystal diffraction analysis revealed that the pdh ligands exhibit a special µ4-bridging mode in compound 1, which link Zn(II) centers into a 2D layered structure. The photocatalysis analysis indicates that it is a potential visible light catalyst. In addition, the solid photoluminescence property of compound 1 was also investigated.

Micheliolide alleviates hepatic steatosis in db/db mice by inhibiting inflammation and promoting autophagy via PPAR-γ-mediated NF-кB and AMPK/mTOR signaling.

The anti-inflammatory, immunomodulatory, and anticancer effects of micheliolide (MCL) isolated from Michelia champaca were previously reported, but its role and underlying mechanisms in relieving liver steatosis remain unclear. Herein, we investigated the effects of MCL on hepatic steatosis using a db/db mouse model and lipid mixture (LM)-induced AML12 and LO2 cells. The body and liver weights, food consumption, lipid content and liver aminotransferase levels in serum, the lipid content and inflammatory cytokine levels in liver tissue, and the extent of hepatic steatosis in db/db mice were increased compared with those in db/m mice, and these increases were reversed by MCL treatment. Similarly, MCL also attenuated the inflammatory responses and lipid accumulation in LM-treated AML12 and L02 cells by upregulating PPAR-γ and decreasing p-IкBα and p-NF-κB/p65, thereby inhibiting the NF-κB pathway and reducing lipotoxicity. Furthermore, MCL administration increased LC3B, Atg7 and Beclin-1 expression and the LC3B-II/I ratio in db/db mouse livers and LM-treated AML12 and L02 cells, and these MCL-induced increases were mediated by the activation of PPAR-γ and p-AMPK and inhibition of p-mTOR and induce autophagy. These effects were blocked by PPAR-γ and AMPK inhibitors. Our findings suggest that MCL ameliorates liver steatosis by upregulating PPAR-γ expression, thereby inhibiting NF-κB-mediated inflammation and activating AMPK/mTOR-dependent autophagy.