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Si 3 N 4 ceramics, due to their exceptional comprehensive performance, have potential applications in electronic products under the 5th generation mobile communication technology. However, their development is hindered by a lack of color variety and inherent brittleness. To address these issues, we propose the use of an appropriate colorant-sintering additive to enhance densification, promote the growth of β grains and facilitate the formation of a chromogenic phase. This approach aims to simultaneously adjust the color and mechanical properties of Si 3 N 4 ceramics. STEM-EDS results indicate the presence of Re-enriched hollow structures within the Si 3 N 4 matrix. These hollow structures may serve as one of the color centers of silicon nitride. The combined effects of the stress field surrounding the hollow structure, elongated β-Si 3 N 4 grains and intensive dislocations result in strong mechanical properties of Si 3 N 4 ceramics, in which the flexural strength is 852.7 ± 55.8 MPa and the fracture toughness is 11.7 ± 1.0 MPa m1/2. [ABSTRACT FROM AUTHOR]

Antiferroelectric ceramics can realize ultra-high energy storage, which benefits from transformation between an antiferroelectric phase and a ferroelectric phase. Understanding the mechanism of such phase transition is the key point for building the structure-property correlation. Here, we report the observation of electric-induced devil's staircase in the course of antiferroelectric–ferroelectric phase transition in PbZrO3-based antiferroelectric ceramics by in situ transmission electron microscopy. The dynamic evolution as-revealed in both reciprocal- and real-space involves stepwise rather than monotonic increase in modulation periods along with simultaneous proliferation of nanodomains. Desynchrony of phase transition is observed for incommensurate domains with different initial modulation periods within a single antiferroelectric domain. Then, the synergistic effect of the devil's staircase and as small as possible the initial modulation period is believed to contribute to the superior energy-storage performance. These findings will be helpful for the development of theories for antiferroelectric–ferroelectric phase transition and the design of high-power antiferroelectric materials. [ABSTRACT FROM AUTHOR]

Si3N4 ceramics have been attractive casing materials for electronics devices under the 5th generation mobile communication technology because of its outstanding comprehensive properties. However, single color cannot meet the needs of most consumers. Here, a typical strategy, involving forming core‐shell structures by utilizing Nd2O3‐MgO‐YAG system, is proposed to rich color. Scanning transmission electron microscope‐energy dispersive X‐ray spectrometry results confirm the presence of core‐shell structures in the silicon nitride matrix, and the core is pore and the shell is Nd‐enriched liquid phase. The Nd‐rich core‐shell structure as the color center makes the silicon nitride appear cyan or blue. [ABSTRACT FROM AUTHOR]

Antiferroelectric (AFE) ceramics are the most promising material system for energy storage in dielectric capacitors due to their fast charging-discharging rate, good chemical stability, and high energy storage density. However, it is exceedingly challenging to simultaneously achieve the excellent recoverable energy density (W re) and high energy storage efficiency (η) at present. In this work, (Pb 0.925-x Sr x La 0.05)(Hf 0.95 Ti 0.05)O 3 AFE ceramics with various Sr contents are fabricated by solid-state sintering processing. It has been found that Sr-doping in the A-site can significantly affect the microstructure, including reducing grain size and modulation period, effectively strengthening the antiferroelectricity, which is responsible for the improved energy storage performance. The high recoverable energy storage density of 10.2 J/cm3 is obtained at 560 kV/cm with an ultra-high efficiency of 93.0% in (Pb 0.875 Sr 0.05 La 0.05)(Hf 0.95 Ti 0.05)O 3 ceramics. These features suggest that Sr-doped PbHfO 3 -based AFE ceramics can serve as promising candidates for capacitor materials, offering significant potential in the realm of energy storage applications. [Display omitted] • Novel PbHfO 3 -based antiferroelectric ceramics with slim P-E loops are prepared. • A W re of 10.2 J/cm3 and a η of 93.0% are achieved in (Pb 0.875 Sr 0.05 La 0.05)(Hf 0.95 Ti 0.05)O 3 ceramic. • Great energy storage from factors like smaller grain size, well elemental distribution and varied modulation structures. [ABSTRACT FROM AUTHOR]

Hydrological processes are known as major driving forces in structuring wetland plant communities, but the specific relationships are not always well understood. The recent dry conditions of Poyang Lake (i.e., the largest freshwater lake in China) are having a profound impact on its wetland vegetation, leading to the degradation of the entire wetland ecosystem. We developed an integrated framework to quantitatively investigate the relationship between the spatial distribution of major wetland herbaceous communities and the hydrological regimes of Poyang Lake. First, the wetland herbaceous community classification was built using a support-vector machine and simultaneous parameter optimization, achieving an overall accuracy of over 98%. Secondly, based on the inundation conditions since 2000, four hydrological drivers of the spatial distribution of these communities were evaluated by canonical correspondence analysis. Finally, the hydrological niches of the communities were quantified by Gaussian regression and quantile methods. The results show that there were significant interspecific differences in terms of the hydrological niche. For example, Carex cinerascens Ass was the most adaptable to inundation, while Triarrhena lutarioriparia + Phragmites australis Ass was the least. Our integrated analytical framework can contribute to hydrological management to better maintain the wetland plant community structure in the Poyang Lake area. [ABSTRACT FROM AUTHOR]

In this paper, silicon nitride (Si3N4) ceramics with black color and high toughness were fabricated by gas pressure sintering and characterized by X‐ray diffraction, Raman, scanning electron microscopy, EDS, and transmission electron microscopy. The in situ formed cobalt silicide was confirmed to contribute to the black color through the introduction of CoO. Due to the addition of CoO, the growth of β‐Si3N4 grains is promoted, forming elongated grains, and eventually forms the self‐reinforcing microstructure. However, with adding excessive CoO, interfacial debonding is found between cobalt silicide and Si3N4 matrix and a decrease in strength was resulted. The optimum composition is 1 mol% CoO in Si3N4, with the fracture toughness of 9.9 ± 0.3 MPa m1/2, flexural strength of 826.1 ± 46.0 MPa, and a much darker black color. The mechanism of color formation is discussed where the black color derives mainly from the metallic silicon and additionally the porosity. [ABSTRACT FROM AUTHOR]

Antiferroelectric and ferroelectric materials are prominent non-linear dielectric materials with significant applications across various fields. To fully understand their electrical properties, it is crucial to accurately discriminate the two phases, especially in compositions with the coexistence of antiferroelectric and ferroelectric phases. In this study, we propose an easy method for differentiating domain structures from phase coexistence based on split outskirt reflections. The proposed method addresses existing limitations in the spatial phase distribution and lays the groundwork for understanding their structure–property relationships. [ABSTRACT FROM AUTHOR]

In recent years, intrinsic 2D magnetism has aroused great interest because of its potential application in spintronic devices. However, low Curie temperature (Tc) and magnetic anisotropy energy (MAE) limit its application prospects. Here, using first‐principles calculations based on density‐functional theory, a series of stable MnXSe4 (X=As, Sb) single‐layer is predicted. The MAE of single‐layer MnAsSe4 and MnSbSe4 is 648.76 and 808.95 μeV per Mn atom, respectively. Monte Carlo simulations suggest the Tc of single‐layer MnAsSe4 and MnSbSe4 is 174 and 250 K, respectively. The energy band calculation with hybrid Heyd–Scuseria–Ernzerhof (HSE06) function indicates the MnXSe4 (X = As, Sb) is ferromagnetic half‐metallic. Also, it has 100% spin‐polarization ratio at the Fermi level. For MnAsSe4 and MnSbSe4, the spin‐gaps are 1.59 and 1.48 eV, respectively. These excellent magnetic properties render MnXSe4 (X = As, Sb) as promising candidate materials for 2D spintronic applications. [ABSTRACT FROM AUTHOR]

(Pb, La)(Zr, Sn, Ti)O 3 (PLZST) ceramic is one of the most prospective antiferroelectric (AFE) materials for variety of functional applications including energy storage and converter. Systematic structural investigation of domain structures should be of fundamental importance for understanding the structure-property relationship in AFE ceramics. In this study, the hierarchical domain structures and modulated structures correlated to the compositional variation in (Pb 0.97 La 0.02) (Zr 0.50 Sn x Ti 0.50-x)O 3 (x = 0.375, 0.45 and 0.50) were observed and investigated in details by transmission electron microscopy. The PLZST ceramics show exclusively incommensurate modulated structures (IMS) whose modulation period changed from 9.37 to 6.15 and to 4.04 with increasing of the x value. The hierarchical domain structures include, in decreasing scales, AFE domains, incommensurate domains and nanodomains. The elementary domains in PLZST ceramics are pinstriped nanodomains which were formed based on IMS configuration but by frequent modulation of IMS periodicity and formation of faults. Nanodomains accumulated and then dissociated into incommensurate domains and AFE domains successively. The presently revealed structural characteristics in antiferroelectric PLZST may stimulate future researches on the evolution of IMS-based hierarchical domains under external physical fields, e.g. thermal or electrical, and their correlation to the physical performance. [ABSTRACT FROM AUTHOR]

• Aroma characteristics of Fu brick tea were classified into three types. • Key aroma compounds in three aroma types of Fu brick tea were identified. • Determine the contribution of aroma compounds in different types of Fu brick tea. Fu brick tea (FBT) is popular for its unique 'fungal flower' aroma, however, its key odor-active compounds are essentially unknown. In this study, the odor-active compounds of "stale-fungal" aroma (CJX), "fresh-fungal" aroma (QJX), and "fermentation-fungal" aroma (FJX) types FBT were extracted and examined by headspace solid phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC–MS) and gas chromatographyolfactometry (GC-O). A total of 43 volatile and 38 odor-active compounds were identified by these methods. Among them, the content of dihydroactindiolide (4596–13189 µg/L), (E) -linalool oxide (2863–6627 µg/L), and benzyl alcohol (4992–6859 µg/L) were highest. Aroma recombination experiments further verified that these odor-active compounds could be simulated the overall aroma profile of FBT successfully. Furthermore, omission experiments confirmed that 15, 20, and 15 key odor-active compounds in CJX, QJX, and FJX FBT, respectively. This study will provide a theoretical basis for comprehensively understanding the formation of characteristic aromas in FBT. [ABSTRACT FROM AUTHOR]

Reservoir operations significantly alter the hydrological regime of the downstream river and river-connected lake, which has far-reaching impacts on the lake ecosystem. To facilitate the management of lakes connected to regulated rivers, the following information must be provided: (1) the response of lake water levels to reservoir operation schedules in the near future and (2) the importance of different rivers in terms of affecting the water levels in different lake regions of interest. We develop an integrated modeling and analytical methodology for the water level management of such lakes. The data-driven method is used to model the lake level as it has the potential of producing quick and accurate predictions. A new genetic algorithm-based synchronized search is proposed to optimize input variable time lags and data-driven model parameters simultaneously. The methodology also involves the orthogonal design and range analysis for extracting the influence of an individual river from that of all the rivers. The integrated methodology is applied to the second largest freshwater lake in China, the Dongting Lake. The results show that: (1) the antecedent lake levels are of crucial importance for the current lake level prediction; (2) the selected river discharge time lags reflect the spatial heterogeneity of the rivers’ impacts on lake level changes; (3) the predicted lake levels are in very good agreement with the observed data (RMSE ≤ 0.091 m; R 2  ≥ 0.9986). This study demonstrates the practical potential of the integrated methodology, which can provide both the lake level responses to future dam releases and the relative contributions of different rivers to lake level changes. [ABSTRACT FROM AUTHOR]

Lead-free antiferroelectric materials can be used in environmental-friendly energy applications and are receiving tremendous attention owing to their high energy-storage density, which is achieved through a phase transition between antiferroelectric and ferroelectric state. Here, by slowing down the antiferroelectric-ferroelectric transition via controllable beam irradiation in a transmission electron microscope, we demonstrate that such a transition in NaNbO 3 undergoes by means of forming a buffer-area (about 40–150 nm wide) at the on-going transition front. The spatial buffer-area approximately maintains its shape during moving and are characterized to be the antiferroelectric phase but exhibits a gradual variation of lattice spacing along the [010] proceeding direction of phase transition. With help of such buffer-area, the overall stress or barrier between the two phases could be considerably reduced compared to the direct change between the two structures. Therefore, our findings provide new insights for understanding the dynamical energy-storage process in antiferroelectric materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Prostate cancer is one of the most common malignancies in men. Members of the elongation of the very-long-chain fatty acid (ELOVL) gene family have been reported to participate in the occurrence and development of various cancers. However, the function of ELOVL gene family members (ELOVLs) in prostate cancer has not been fully elucidated. The mRNA expression and prognostic value of ELOVLs in prostate cancer were analyzed using the GEPIA database. The Oncomine database and PrognoScan database were used to further verify the mRNA expression level and prognostic value of ELOVL2 in prostate cancer. RT–qPCR and Western blotting were used to validate the expression levels of ELOVL2 in four prostate cancer cell lines. Immunohistochemistry was performed to detect the ELOVL2 protein expression levels in prostate cancer tissues. Coexpression analysis in the cBioPortal database and enrichment analysis in Kyoto Encyclopedia of Genes and Genomes (KEGG), CCK8, colony formation, and transwell assays were used to identify the functions and mechanisms of ELOVL2. ELOVL2 expression was upregulated in prostate cancer tissues compared with normal tissues. High expression of ELOVL2 indicated a better prognosis in prostate cancer patients. ELOVL2 expression was negatively correlated with Gleason score. Knockdown of ELOVL2 promoted cell proliferation, colony formation, migration, invasion, and the growth of subcutaneous xenografts and activated the PI3K/Akt signaling pathway by downregulating INPP4B, while overexpression of ELOVL2 reversed these effects. In addition, overexpression of INPP4B blocked the promoting effect of sh-ELOVL2 on cell proliferation, colony formation, migration, invasion, and the PI3K/Akt signaling pathway. Our findings suggest that ELOVL2 might be a prognostic biomarker and therapeutic target for prostate cancer. • High expression of ELOVL2 is associated with a better prognosis in prostate cancer patients. • ELOVL2 inhibits prostate cancer cell proliferation, colony formation, migration, and invasion. • Overexpression INPP4B blocks the promoting effect of knocking down ELOVL2 to prostate cancer. • ELOVL2 plays the tumor suppressor role by INPP4B/PI3K/Akt signaling pathway in prostate cancer. [ABSTRACT FROM AUTHOR]

Based on the introduction of concept of forest lifter, changes in the amount of forest lifter with climate zone, elevation, forest type and age of stand were analyzed, and then the decomposition of forest lifter was discussed. [ABSTRACT FROM AUTHOR]

The electrochemical performance of all‐solid‐state lithium batteries (ASSLBs) can be significantly improved by addressing the challenges posed by space charge layer (SCL) effect, which plays a crucial role in determining Li+ ions transport kinetic at cathodic interface. Therefore, it is critical to realize the in situ inspection and visualization of SCL behaviors for solving sluggish Li+ ions transport issues, despite remaining grant challenges. Therewith, the well‐defined model of LiNbO3‐coated NCM (NCM@LNO) cathode is constructed and assembled for the representative Li6PS5Cl‐based ASSLBs, which not only ensures excellent cathodic compatibility, but also preferably enables the better monitoring of Li+ ions transport kinetics. Combining ex situ analysis with DFT calculation, the formation and evolution mechanism of SCL are comprehensively understood, and the relationship between well‐controlled SCL configuration and Li+ electrochemical behavior has been also further illustrated and established through the operando Raman spectroscopy. On these grounds, the preferred NCM@LNO cathodes acquire the enhanced discharge capacity of 90.6% (144.8 mAh g−1) after 100 cycles and it can still deliver the exceptional capacity of 136.2 mAh g−1 after 800 cycles in ASSLBs. Hence, the research will pave up a new perspective for fundamental scientific insight of the SCL and reasonable tailoring of cathodic interface for high‐efficiency ASSLBs. [ABSTRACT FROM AUTHOR]

SUMMARY: Gibberellins (GAs) play crucial roles in regulating plant architecture and grain yield of crops. In rice, the inactivation of endogenous bioactive GAs and their precursors by GA 2‐oxidases (GA2oxs) regulates stem elongation and reproductive development. However, the regulatory mechanisms of GA2ox gene expression, especially in rice reproductive organs, are unknown. The BEL1‐like homeodomain protein OsBLH4, a negative regulatory factor for the rice OsGA2ox1 gene, was identified in this study. Loss of OsBLH4 function results in decreased bioactive GA levels and pleiotropic phenotypes, including reduced plant height, decreased grain number per panicle, and delayed heading date, as also observed in OsGA2ox1‐overexpressing plants. Consistent with the mutant phenotype, OsBLH4 was predominantly expressed in shoots and young spikelets; its encoded protein was exclusively localized in the nucleus. Molecular analysis demonstrated that OsBLH4 directly bound to the promoter region of OsGA2ox1 to repress its expression. Genetic assays revealed that OsBLH4 acts upstream of OsGA2ox1 to control rice plant height, grain number, and heading date. Taken together, these results indicate a crucial role for OsBLH4 in regulating rice plant architecture and yield potential via regulation of bioactive GA levels, and provide a potential strategy for genetic improvements of rice. Significance Statement: GA 2‐oxidases (GA2oxs) play crucial roles in regulating plant architecture and yield by inactivating endogenous bioactive GAs and their precursors, but the regulatory mechanisms of GA2ox gene expression remain unclear. This study identifies that OsBLH4, a member of the BEL1‐like homeodomain proteins, acts upstream of OsGA2ox1, modulates endogenous bioactive GA levels, and regulates stem elongation and reproductive development in rice. [ABSTRACT FROM AUTHOR]

• A new 2D magnet, CrAsS 4 , may be useful for spintronics applications. • Phase transition of CrAsS 4 from AFM to FM state happens under a strain. • The mechanism of strain-dependent magnetic stability was further elucidated. Using first-principles calculations based on density-functional theory, the effects of strain on the magnetic order and band structure of single-layer CrAsS 4 have been investigated systematically. By applying a uniaxial tensile strain of 2.99% along the y-direction or a compressive strain of 1.76% along the x-direction, the single-layer CrAsS 4 is determined to be an antiferromagnetic (AFM) semiconductor that undergoes a phase transition from AFM to ferromagnetic (FM) state. Further, the physical mechanism underlying the strain-dependent magnetic stability is discovered to be a competition between direct exchange and indirect superexchange interactions between the nearest neighbour Cr atoms. Moreover, the bandgap exhibits an abrupt change that accompanies the phase transition in the magnetic order. Our study provides an intuitive approach to design the strain-modulated spintronic devices. [ABSTRACT FROM AUTHOR]

The significant role of cell-free DNA (cfDNA) for disease diagnosis, including cancer, has garnered a lot of attention. The challenges of creating target-specific primers and the possibility of false-positive signals make amplification-based detection methods problematic. Fluorescent biosensors based on CRISPR-Cas have been widely established, however they still require an amplification step before they can be used for detection. To detect cfDNA, researchers have created a CRISPR-Cas12a-based nucleic acid amplification-free fluorescent biosensor that uses a combination of fluorescence and colorimetric signaling improved by duplex-specific nuclease (DSN). DSN-assisted signal recycling is initiated in H1@MBs when the target cfDNA activates the CRISPR-Cas12a complex, leading to the degradation of single-strand DNA (ssDNA) sequences. This method has an extremely high detection limit for the BRCA-1 breast cancer gene. In addition to measuring viral DNA in a field-deployable and point-of-care testing (POCT) platform, this fast and highly selective sensor can be used to evaluate additional nucleic acid biomarkers. [Display omitted] • The approach output both colorimetry and fluorescence signals. • The approach is highly-possible to greatly reduce outside noise and increase the precision of the analysis. • The approach displays remarkable selectivity thanks to CRISPR-Cas12a system based accurate target recognition. [ABSTRACT FROM AUTHOR]

With the gradual promotion of new energy technologies, there is a growing demand for capacitors with high energy storage density, high operating temperature, high operating voltage, and good temperature stability. In recent years, researchers have been devoted to improving the energy storage properties of lead‐based, titanium‐based, and iron‐based multilayer ceramic capacitors (MLCCs). However, limited research has been conducted into MLCC development using NaNbO3 (NN)‐based materials. In this paper, the successful achievement of excellent overall energy storage performance in a novel NaNbO3–(Bi0.5Na0.5)TiO3–Bi(Mg0.5Hf0.5)O3 lead‐free MLCCs is presented. The disordered tilting around the cp axis, disrupts Na and Bi ions' long‐range displacements and induces PNRs and strong relaxor behavior, which ensures a superior energy storage performance, together with the multilayer ceramic design strategy. As a result, the NN‐based MLCC device presents an ultra‐high Wrec = 12.65 J cm−3 and η = 88.5%, simultaneously showing superior temperature stability (Wrec varies <±1% and η varies <±6% from −50 to 125 °C) and fatigue resistance (Wrec and η vary <±1% over 107 cycles). This study highlights the advanced energy storage potential of NaNbO3‐based MLCCs for various applications, and ushers in a new era for designing high‐performance lead‐free capacitors that can operate in harsh environments. [ABSTRACT FROM AUTHOR]

The capacitors are in rising demand for cryogenic applications. As for now, it still remains an ongoing challenge for simultaneously achieving high energy storage density and cryogenic temperature stability. Herein, the strategy of stable backward phase transition was demonstrated in the antiferroelectric composition of (Pb0.9175La0.055)(Zr0.975Ti0.025)O3. As a result, we achieved high recoverable energy density about 10 J/cm3 with exceptional low-temperature stability from −160 to 25 °C. Multi-layer ceramic capacitors designed for pulse discharge applications also demonstrated high performance in cryogenic conditions, with the peak current fluctuations of less than 4%. Through in situ characterizations using x-ray diffraction, Raman spectra, and transmission electron microscopy, we discovered that the anisotropic structural evolution is responsible for a stable backward phase transition, providing the material with robust stability at cryogenic temperatures. These results offer a good paradigm for improving the temperature stability of antiferroelectric multi-layer capacitors to meet the rigorous demands of energy storage applications. [ABSTRACT FROM AUTHOR]

• The composite ceramics Bi 0.5 Na 0.5 TiO 3 -Sm 2 Ti 2 O 7 were successfully prepared. • Excellent electrical properties and stability are obtained in BNT-STO ceramics. • A new effective method to design high ESP ceramic materials is proposed. The comprehensive performance of ferroelectric ceramic materials is a significant factor limiting the practical application. In this work, a novel strategy of constructing diphase compounds is proposed to significantly enhance the energy storage properties of Bi 0.5 Na 0.5 TiO 3 -based ceramics. A composite ceramic of pyrochlore phase Sm 2 Ti 2 O 7 modified perovskite phase Bi 0.5 Na 0.5 TiO 3 is successfully prepared and systematically studied. As the concentration of Sm 2 Ti 2 O 7 increases, the dielectric breakdown strength is greatly strengthened because of expanded band gap and shrunk grain size, and the relaxor behavior is enhanced due to the effect of linear character pyrochlore. As a result, the optimized composition demonstrates excellent energy storage properties including high recoverable energy storage density (W rec) of 6.387 J/cm3 at 402 kV/cm, superior stability of temperature (<6% variation in − 120 ∼ 120 °C), frequency (∼4% variation in 5 ∼ 500 Hz) and cycling (∼2% variation within 106 cycles). Besides, fast discharge behavior of t 0.9 ∼ 29.4 ns and high power density of 80.49 MW/cm3 at 200 kV/cm are also achieved. This study presents a novel strategy to enhance the performance of BNT-based materials through forming composite ceramic, which is anticipated to be a general method for other material systems as regards the design of advanced energy storage ceramics. [ABSTRACT FROM AUTHOR]

Firstly, the connotations and influencing factors of ecosystem health are discussed, and then the assessment principle, evaluation standard and evaluation method of ecosystem health and the establishment and measurement of ecosystem health indicators are studied. Through the study of its connotation and evaluation, feasible measures to effectively promote the development of ecosystem health are put forward finally. [ABSTRACT FROM AUTHOR]

Zero voltage switching (ZVS) techniques are widely utilized to increase efficiency and reduce electromagnetic interference of wireless power transfer (WPT) systems. Hybrid frequency pacing (HFP) is an excellent modulation method for WPT systems because it can achieve full-load range ZVS without changing the current frequency or adding auxiliary components. Another advantage of HFP is the average switching frequency reduction as decreasing output voltage so that it further reduces switching losses. This article provides an insight into the characteristics of HFP and points out that a large output ripple occurs under some reference conditions. To improve HFP, this article proposes an improved HFP (iHFP) method to minimize output ripple by optimally arranging the hybrid frequencies pulse sequence, but the implementation process of iHFP becomes more complicated. The reason for the unavoidable complicated calculation of HFP is the quantization error. In this viewpoint, this article proposes a modified sigma-delta modulation method with the quantization noise-shaping property for iHFP. As a consequence, the same pulse sequence can be generated by this simple modulator without complex calculations. Experimental results show that iHFP and Σ-Δ  iHFP can reduce more than 60% voltage fluctuations compared with HFP. Under 0.2% input reference resolution, 66%–93% computational time reduction is achieved in going from HFP to Σ-Δ iHFP. [ABSTRACT FROM AUTHOR]

Relaxor ferroelectric (FE) ceramic capacitors have attracted increasing attention for their excellent energy‐storage performance. However, it is extremely difficult to achieve desirable comprehensive energy‐storage features required for industrial applications. In this work, very high recoverable energy density Wrec ≈ 8.73 J cm–3, high efficiency η ≈ 80.1%, ultrafast discharge rate of <85 ns, and temperature‐insensitive high Wrec and η (Wrec ≈ 5.73 ± 4% J cm–3, η ≈ 75 ± 6%, 25–200 °C) are simultaneously obtained in 0.68NaNbO3‐0.32(Bi0.5Li0.5)TiO3 relaxor FE ceramics by introducing various polarization configurations in combination with microstructure modification. The structure mechanism for the excellent energy‐storage performance is disclosed by analyzing in situ structure evolution on multiple scales during loading/unloading by means of transmission electron microscopy and Raman spectroscopy. Both local regions consisting of different‐scale polar nanodomains and a nonpolar matrix, and local orthorhombic symmetry remaining with electric fields ensure a linear‐like polarization response within a wide field and temperature range owing to significantly delayed polarization saturation. The stabilization of orthorhombic FE phases rather than antiferroelectric orthorhombic phases in NaNbO3 after adding (Bi0.5Li0.5)TiO3 is also explored by means of X‐ray diffraction, dielectric properties, and selected area electron diffraction. In comparison with antiferroelectric ceramics, NaNbO3‐based relaxor FE ceramics provide a new solution to successfully design next‐generation pulsed power capacitors. [ABSTRACT FROM AUTHOR]

• The lead-free bismuth sodium titanate ceramic can be polarized in kg-level for 2e- ORR. • The local electric field is triggered in sodium titanate ceramic under dynamic ORR process. • Local electric field improves the ion (OH-/HO 2 −) concentration around the catalyst-electrolyte interface. • An enhanced alkaline 2e- ORR performance is realized on the polarized ceramic catalyst. Optimizing the interface property of the catalyst-electrolyte by the physical field modulation could improve the electrocatalytic performance, yet the associated investigations on the two-electron oxygen reduction reaction (2e− ORR) are still scarce. Herein, we develop a facile, green, and economic piezoelectricity-indued local electric field strategy based on the piezo-response of the polarized lead-free bismuth sodium titanate (P-BNT) ceramic under the dynamic operational conditions of ORR. The as-emerged electric field at the immediate vicinity of the ceramic catalyst surface greatly optimizes its adjacent OH- coverage from the alkaline electrolyte and lowers the local concentration of the HO 2 − product. Therefore, the adsorption ability of oxygen-containing intermediates during the ORR process is ameliorated, and the peroxide product disproportionation is simultaneously inhibited. Compared with the unpolarized ceramic catalyst, P-BNT prepared at a kilogram scale displayed excellent 2e- ORR selectivity over 90% in a wide potential window of 0.45 V in 0.1 M KOH with a summit of ∼100%, outmatching most state-of-the-art alkaline 2e− ORR catalysts. The current work could realize the improved electrosynthesis efficiency of hydrogen peroxide with practical application potentials, especially considering the environmentally-friendly, extensively-studied, and technically-mature lead-free piezoelectric BNT ceramic that can be facilely prepared in a low cost and large scale. [Display omitted] [ABSTRACT FROM AUTHOR]

Utilizing biomass as carbon precursor for peroxydisulfate (PDS) catalyst preparation could solve the problem of solid waste and water pollution treatment synergistically. However, the poor activity of pure biomass catalyst (BC) still needs further improvement. In this study, novel S-doped BC (S-BC) was prepared from chitosan (waste from agriculture and food industry) for PDS activation. With S doping, superior conductivity and defect (active sites) degree were achieved in S-BC. About 99.73% removal efficiency of methyl orange (MO) could also be achieved under the conditions of 3 mM PDS, 1.0 g L−1 S-BC, 10 mg L−1 MO, and initial pH of 3. This removal efficiency is higher than that of BC at 58.46%. Density functional theory calculation showed that the S 2 O 8 2− ions were favorably adsorbed on the S-BC surface due to the negative adsorption energy of −3.048 eV. The O atoms in S–O bond (in S 2 O 8 2−) could capture electrons from S atoms (in S-BC), leading the favorable breaking of this bond. Thus, resulting in the formation of surface attached radicals, O 2 ·− and 1O 2 for MO degradation, rather than SO 4 −· radicals in solution. [Display omitted] • Novel S-BC was prepared from solid waste of chitosan for PDS activation. • Superior conductivity and defect (active sites) degree were achieved with S doping. • Surface attached radicals, O 2 ·− and 1O 2 were contributed for MO degradation, rather than SO 4 −· radicals in solution. [ABSTRACT FROM AUTHOR]

With the continuous development of human society and economy and the continuous progress of industrial technology, more and more pollutants are discharged into the natural environment, and soil environment is also affected at the same time. Among pollutants leading to soil pollution, heavy metals have resulted in most serious soil pollution. Here, many control and restoration approaches to soil pollution from heavy metals are proposed, and characteristics and applicable conditions of various methods are compared, so as to provide theoretical references tor the control and restoration of soil pollution from heavy metals in future. [ABSTRACT FROM AUTHOR]

• This study diagrammed the variant spectrum of CFTR gene in Chinese CAVD patients. • p.Q1352H is the most common and important missense variant in Chinese CAVD patients. • p.I556V and c.-8G > C both show a weak pathogenic effect in CAVD. To find the variant spectrum of the cystic fibrosis transmembrane conductance regulator (CFTR) gene, and evaluate its frequent variants in Chinese congenital absence of vas deferens (CAVD) patients. A total of 276 patients with azoospermia and CAVD (aged from 21 to 44 years old) were investigated from May 2013 to September 2019 in the Third Affiliated Hospital of Sun Yat-sen University. Additionally, 50 healthy, unrelated volunteers were recruited as controls (aged from 21 to 46 years old). The 5′-UTR, exons and their flanking side of the CFTR gene were sequenced by high-throughput sequencing technology. The results were compared with those retrieved from the Ensembl Genome Browser. In addition, all 13 novel variants were further confirmed independently by Sanger sequencing and evaluated in the bioinformatics web servers. A schematic of the variant spectrum of the CFTR gene, including 13 novel variants (12 in CAVD patients, one in the control group), is shown, and the frequent variants in Chinese CAVD patients were 5 T (27.54%), c.-8G > C (7.25%), p.Q1352H (5.98%), and p.I556V (3.08%). 5 T was found to be the most frequent variant. p.Q1352H had a significantly high allelic frequency in CAVD patients (P < 0.05). c.-8G > C and p.I556V had high allelic frequencies but showed no difference between patients and controls (P > 0.05). p.Q1352H is the most common and important missense variant in Chinese patients with CAVD, while the pathological effects of C.-8G > C and p.I556V may be weak after evaluation. [ABSTRACT FROM AUTHOR]