Breaking the trade-off between capacity and stability in vanadium-based zinc-ion batteries.

Water in electrolytes is a double-edged sword in zinc-ion batteries (ZIBs). While it allows for proton insertion in the cathode, resulting in a significant increase in capacity compared to that of organic ZIBs, it also causes damage to electrodes, leading to performance degradation. To overcome the capacity-stability trade-off, organic solvents containing a small amount of water are proposed to mitigate the harmful effects of water while ensuring sufficient proton insertion. Remarkably, in a Zn(OTf)2 electrolyte using 8% H2O in acetonitrile as the solvent, Zn‖(NH4)0.5V2O5·0.5H2O exhibited a capacity as high as 490 mA h g-1 at a low current (0.3 A g-1), with a capacity retention of 80% even after 9000 cycles at high current (6 A g-1), simultaneously achieving the high capacity as in pure aqueous electrolytes and excellent stability as in organic electrolytes. We also found that the water content strongly impacts the kinetics and reversibility of ion insertion/extraction and zinc stripping/plating. Furthermore, compared to electrolytes with pure acetonitrile or H2O solvents, electrolytes with only 8% H2O in acetonitrile provide higher capacities at temperatures ranging from 0 to -50 °C. These discoveries enhance our understanding of the mechanisms involved in ZIBs and present a promising path toward enhancing electrolyte solutions for the creation of high-performance ZIBs.

Discomfort estimation for aircraft cabin noise using linear regression and modified psychoacoustic annoyance approaches.

Appropriate sound quality models for noise-induced discomfort are necessary for a better acoustic comfort design in the aircraft cabin. This study investigates the acoustic discomfort in two large passenger aeroplanes (i.e., planes A and B). We recorded the noise at 21 positions in each aircraft cabin and selected 42 stimuli ranging from 72 to 81 dB(A) during the cruising flights. Twenty-four participants rated the noise discomfort by the absolute magnitude estimation method. The discomfort values in the middle section of the aircraft cabin are 10% points higher than in the front or rear section. The discomfort magnitude was dominated by loudness and influenced by roughness and sharpness. A multiple linear (MA) discomfort model was established, accounting for the relationship between the discomfort and sound quality metrics (i.e., loudness, sharpness, and roughness). The MA model estimated noise discomfort better than the Zwicker and other (i.e., More and Di) psychoacoustic annoyance (PA) models. We modified the coefficients of independent variables in the formulations of Zwicker, Di, and More PA models, respectively, according to the present experimental results. The correlation coefficients between the estimated and measured values of the modified models were at least 20% points higher than the original ones.

Atomic scale analysis of Zn2+ storage in robust tunnel frameworks.

Realizing rapid and reversible Zn2+ storage at the cathode is imperative for the advancement of aqueous Zn-ion batteries (ZIBs), which offer an excellent option for large-scale electrochemical energy storage. However, owing to limitations of the structural stability of previously investigated frameworks, the Zn2+ storage processes remain unclear, thus hindering progress towards the above goal. Herein, we present the novel application of MoVTe oxide with an M1 phase (MVT-M1) as a potential cathode material for ZIBs. MVT-M1 features broad and robust tunnels that facilitate reversible Zn2+ insertion/extraction during cycling, as well as rich redox centers (Mo, V, and Te) to aid in charge redistribution, resulting in good performances in ZIBs. The exceptional resilience of MVT-M1 to high-energy electron beams allows for direct observation of Zn2+ insertion/extraction at the atomic scale within the tunnels for the first time using high-angle annular dark field scanning transmission electron microscopy; the storage location of zinc ions within the cathode is accurately determined layer by layer from the surface to the bulk phase by employing time-of-flight secondary ion mass spectrometry. Additionally, solvent molecules (H2O and methanol) are also found inside the tunnels along with Zn2+. Due to the broader heptagonal tunnels and Te ions in the hexagonal tunnels, MVT-M1 exhibits good cycling stability, outperforming MoVTe oxide with the M2 phase (no heptagonal tunnels) and MoV oxide with the M1 phase (no Te). These findings hold significant importance in advancing our understanding of the Zn2+ storage mechanism and enable the design of novel materials specifically optimized for efficient Zn2+ storage.

Critical Issues of Vanadium-Based Cathodes Towards Practical Aqueous Zn-Ion Batteries.

Aqueous zinc-ion batteries (ZIBs) are gaining significant attention for their numerous advantages, including high safety, high energy density, affordability, and environmental friendliness. However, the development of ZIBs has been hampered by the lack of suitable cathode materials that can store Zn2+ with high capacity and reversibility. Currently, vanadium-based materials with tunnel or layered structures are widely researched owing to their high theoretical capacity and diversified structures. However, their long-term cycling stability is unsatisfactory because of material dissolution, phase transformation, and restrictive kinetics in aqueous electrolytes, which limits their practical applications. Different from previous reviews on ZIBs, this review specifically addresses the critical issues faced by vanadium-based cathodes for practical aqueous ZIBs and proposes potential solutions. Focusing on vanadium-based cathodes, their ion storage mechanisms, the critical parameters affecting their performance, and the progress made in addressing the aforementioned problems are also summarized. Finally, future directions for the development of practical aqueous ZIB are suggested.

Diimidazolium Salt HBDIM: An Easily Available, Low-Cost, CageCarbene Precursor with Broad Applications in Transition Metal-Catalyzed Reactions.

The preparation of diimidazolium salt HBDIM 1, a precursor for a di-NHCs ligand, from cheap and easily available agent hexabenzylhexaazaisowurtzitane (HBIW) is reported. Under basic conditions, HBDIM undergoes facile deprotonation to in situ generate CageCarbene, which could efficiently coordinate to transition-metals, such as, Au, Cu or Pd, to give the corresponding bimetallic complexes 2-4. These complexes were isolated and fully characterized, including X-ray diffraction of their single crystals. It was found that the steric hinderance of CageCarbene is similar to that of SIMes but smaller than that of IPr, and electronically, CageCarbene is a strong σ-donator similar to SIMes and a stronger σ-donator than IPr. Further studies showed that complexes 2-4 were highly reactive to catalyze up to 17 reactions. Control experiments utilizing a N-benzyl-substituted monoimidazolium salt showed much lower catalytic reactivity when it was bound to Au or Cu, but exhibited similar reactivity for the Pd complex. Kinetic studies showed that the low reactivity of the monodentate carbene-ligated Au or Cu complex was due to the low stability of the complex under the reaction conditions.

Enhancing Energy Conversion Efficiency and Durability of Alkaline Nickel-Zinc Batteries with Air-Breathing Cathode.

Despite their high output voltage and safety advantages, rechargeable alkaline nickel-zinc batteries face significant challenges associated with the cathodic side reaction of oxygen evolution, which results in low energy efficiency (EE) and poor stability. Herein, we propose to leverage the side oxygen evolution reaction (OER) in nickel-zinc batteries by coupling electrocatalysts for oxygen reduction reactions (ORR) in the cathode, thus constructing an air breathing cathode. Such a novel battery (Ni-ZnAB), designed in a pouch-type cell with a lean electrolyte, exhibits an outstanding EE of 85 % and a long cycle life of 100 cycles at 2 mA cm-2 , which are significantly superior to those of traditional Ni-Zn batteries (54 %, 50 cycles). Compared to Ni-Zn, the enhanced EE of Ni-ZnAB is attributed to the contribution from ORR, while the improved cycling stability is because the stability of the anode, cathode and electrolyte are also enhanced in Ni-ZnAB. Furthermore, an ultrahigh stability of 500 cycles with an average EE of 84 % at 2 mA cm-2 was achieved using a mold cell with rich electrolyte, demonstrating the strong application potential of Ni-ZnAB.

Association between age and loneliness in different residential type and gender groups: evidence from China.

BACKGROUND: Age has been identified as a prominent predictor of loneliness, although the findings about the relationship between age and loneliness are inconclusive. This study examines the relationship between age and loneliness in the context of China, with a focus on residential and gender differences. METHODS: Data were from the Chinese General Social Survey (CGSS) of 2017. A total of 3899 respondents were included. Loneliness was measured using a three-item Short Loneliness Scale. Age, squared terms of age, residential type, gender, and other socio-demographic characteristics were included in the study. Regression analyses were conducted among the total sample and subgroups of different gender and residential type subgroups, to investigate the association between age and loneliness. RESULTS: There is a reverse U-shaped tendency between age and loneliness that peaks at the age of 47. This tendency is true of the male subgroup, that peaks at the age of 55, while the female respondents do not share that tendency. The inverted U-shaped distribution holds true for urban but not for rural residents. The female respondents reported a higher level of loneliness than the male. The rural respondents reported higher loneliness than their counterparts. CONCLUSIONS: This study demonstrates that an inverted U-shaped tendency between age and loneliness existed for the entire group, and the male and urban subgroups. Implications for service and practice are proposed based on the empirical findings.

Hewettite ZnV6 O16 ⋠8H2 O with Remarkably Stable Layers and Ultralarge Interlayer Spacing for High-Performance Aqueous Zn-Ion Batteries.

Aqueous Zn-ion batteries (ZIBs) are promising candidates for grid-scale energy storage because of their intrinsic safety, low-cost and high energy-intensity. Vanadium-based materials are widely used as the cathode of ZIBs, especially A2 V6 O16 ⋅ nH2 O (AVO, A=NH4 + , Na, K). However, AVO suffers from serious dissolution, phase transformation and narrow gallery spacing (∼3 Å), leading to poor cycling stability and rate capability. Herein, we unveiled the root cause of the performance degradation in the AVO cathode and therefore developed a new high-performance cathode of ZnV6 O16 ⋅ 8H2 O (ZVO) for ZIB. Through a method of ion exchange induced phase transformation, AVO was converted to hewettite ZVO with larger gallery spacing (∼6 Å) and more stable V6 O16 layers. ZVO cathode thus constructed delivers a high capacity of 365 and 170 mAh g-1 at 0.5 and 15 A g-1 , while 86 % and 70 % of its capacity are retained at 0.5 A g-1 after 300 cycles and at 15 A g-1 after 10000 cycles, substantially better than conventional AVO.

Social isolation and loneliness among Chinese older adults: Examining aging attitudes as mediators and moderators.

Due to labor migration and social changes, the Chinese elderly are facing significant social isolation, along with changes in aging attitudes. However, whether social isolation affects loneliness among the Chinese elderly and whether this relationship is moderated and mediated by aging attitudes is unclear. This empirical study aimed to respond to the above questions in the Chinese context, Based on the data from the 2014 China Longitudinal Aging Social Survey (N = 6,645), the results showed that social isolation is a positive predictor of loneliness; aging attitudes mediate the relationship between social isolation and loneliness. Social isolation affects the loneliness of the elderly partially by weakening positive aging attitudes and strengthening negative aging attitudes; aging attitudes moderate the effect of social isolation on loneliness. For those older adults with higher positive aging attitudes, social isolation has a much smaller effect on loneliness. While for those older adults with higher negative aging attitudes, social isolation has a more substantial effect on their feelings of loneliness. Our results indicate that less social isolation is an effective way to relieve loneliness, and maintaining higher positive aging attitudes and lower negative aging attitudes, is important for the Chinese elderly to prevent loneliness when facing social isolation.

Vehicle Stability Analysis under Extreme Operating Conditions Based on LQR Control.

Under extreme working conditions such as high-speed driving on roads with a large road surface unevenness coefficient, turning on a road with a low road surface adhesion coefficient, and emergency acceleration and braking, a vehicle's stability deteriorates sharply and reduces ride comfort. There is extensive existing research on vehicle active suspension control, trajectory tracking, and control methods. However, most of these studies focus on conventional operating conditions, while vehicle stability analysis under extreme operating conditions is much less studied. In order to improve the stability of the whole vehicle under extreme operating conditions, this paper investigates the stability of a vehicle under extreme operating conditions based on linear quadratic regulator (LQR) control. First, a seven degrees of freedom (7-DOF) dynamics model of the whole vehicle is established based on the use of electromagnetic active suspension, and then an LQR controller of the electromagnetic active suspension is designed. A joint simulation platform incorporating MATLAB and CarSim was built, and the CarSim model is verified by real vehicle tests. Finally, the stability of the vehicle under four different ultimate operating conditions was analyzed. The simulation results show that the root mean square (RMS) values of body droop acceleration and pitch angle acceleration are improved by 57.48% and 28.81%, respectively, under high-speed driving conditions on Class C roads. Under the double-shift condition with a low adhesion coefficient, the RMS values of body droop acceleration, pitch acceleration, and roll angle acceleration are improved by 58.25%, 55.41%, and 31.39%, respectively. These results indicate that electromagnetic active suspension can significantly improve vehicle stability and reduce driving risk under extreme working conditions when combined with an LQR controller.

Carbon-encapsulated V2O3 nanorods for high-performance aqueous Zn-ion batteries.

Searching for stable cathodes is of paramount importance to the commercial development of low-cost and safe aqueous Zn-ion batteries (AZIBs). V2O3 is a good candidate for AZIB cathodes but has unsatisfied cycling stability. Herein, we solve the stability issue of a V2O3 cathode by coating a robust carbon shell. Strong evidence was provided that V2O3 was oxidized to favorable V2O5·nH2O during charging and the carbon shell could promote the oxidation of V2O3 to V2O5·nH2O. The discharge capacity was increased from ∼45 mA h g-1 to 336 mA h g-1 after V2O3 was oxidized to V2O5·nH2O, indicating a higher Zn2+-storage capability of V2O5·nH2O than V2O3. In addition, the rate-capability and long-term cycling performance are greatly enhanced after coating carbon shells on the surface of V2O3 nanorods. Therefore, the presented strategy of introducing carbon shells and fundamental insights into the favorable role of carbon shells in this study contribute to the advancement of highly stable AZIBs.

Complementary Acoustic Metamaterial for Penetrating Aberration Layers.

Impedance-matched acoustic materials were developed to improve ultrasound penetration through the aberration layer. The traditional ultrasound layer matching material is called a couplant, which can only enhance ultrasound transmission to soft biological media such as the cartilage and muscle but cannot penetrate hard media such as the bone. Here, we propose a phase-modulated complementary acoustic metamaterial based on the principle of impedance matching, which enables ultrasound to penetrate the bone, and use the equivalent parameter technology of acoustic metamaterials for parameter design. Ultrasonic layer adjustment is performed through 3D printing and corrects bone aberrations. Several configurations were investigated through numerical simulations and experiments in non-reflecting tanks. Specifically, the bone matching layer can be optimally designed for a specific bone thickness and a specific operating frequency of the ultrasound probe, thereby amplifying the ultrasound to penetrate the matching layer and bone. The experimental and simulation results show that the proposed acoustic metamaterial can improve the transmission efficiency of ultrasound through the aberration layer.

Association between dietary patterns and central precocious puberty in girls / 中国学校卫生

Objective@#To explore the relationship between dietary patterns and central precocious puberty in children, and to provide a scientific basis for dietary prevention of precocious puberty.@*Methods@#A case-control study was conducted, among 35 newly diagnosed central precocious puberty girls from May to December 2019 as the case group, and 70 healthy girls with normal development as the control group. Physical development examination, parent questionnaire survey and child interview were carried out. Dietary information was assessed using a simplified food frequency questionnaire(FFQ). Principal component analysis was used to identify children s dietary patterns, and multiple Logistic regression was used to assess the association between dietary patterns and precocious puberty.@*Results@#Three different dietary patterns have been established, namely "snack and processed food type", "animal protein type" and "nutritional tonic type" dietary patterns, respectively. After adjusting for covariates such as age and BMI, Logistic regression analysis showed that the "snack and processed food type" dietary pattern was positively correlated with precocious puberty(OR=10.81, 95%CI=2.59-45.15, P<0.01). There was a negative correlation between "animal protein type" and precocious puberty(OR=0.24, 95%CI=0.06-0.91, P=0.04), while the association between "nutritive tonic" and precocious puberty was not statistically significant(OR=0.28, 95%CI=0.07-1.05, P=0.06).@*Conclusion@#Children s dietary patterns were related to precocious puberty." Snack and processed food "dietary pattern with a high intake of fried foods, puffed foods, foods containing preservatives or pigments, western fast foods, chocolate and products, was closely related to central precocious puberty.

A cohort study on the association between sugar-sweetened beverage intake and childhood obesity using a group-based trajectory model / 中国学校卫生

Objective@#To evaluate the development trajectory of sugar-sweetened beverage (SSB) intake in childhood, and to explore the influence of different SSB intake patterns on childhood obesity.@*Methods@#In 2016, a follow-up cohort study was carried out in two primary schools in Bengbu, Anhui Province. Three annual follow-ups were conducted in 1 263 children at baseline, and 997 children were included in the final analysis. Parental and student questionnaires were used to obtain basic information related to the children s consumption of SSBs. A group-based trajectory model (GBTM) was applied to classify the development trajectory of SSB intake patterns in childhood. Multiple linear regression analyses were performed to assess the correlation between different SSB intake patterns and childhood obesity.@*Results@#GBTM identified four childhood SSB intake patterns, namely, the "persistently-low group (n=822), “decreasing-after-increasing” group (n=20), “gradually-decreasing” group (n=106), and “increasing” group (n=49). In the decreasing-after-increasing group and the gradually-decreasing group, baseline BMI levels and BMI levels obtained at the three follow-ups were significantly higher than those observed in the persistently-low group (F=6.26, 5.90, 5.99, 5.87, P<0.01). There were sex differences in the association between SSB intake patterns and the children s BMI levels. Among girls, after adjusting for confounding factors, the gradually decreasing group increased by 1.20 kg/m 2(B=1.20，95%CI=0.25-2.15, P=0.01) when compared with the persistently low group at the third follow-up. Among boys, no statistically significant association was found between SSB intake patterns and BMI levels (P>0.05).@*Conclusion@#Sex differences were observed with respect to the association between SSB intake patterns and obesity in children. Girls with a higher SSB intake had a significantly increased risk of obesity. Further studies are needed to explore the physiological mechanisms underlying sex differences, to provide the theoretical basis for developing intervention programs to prevent childhood obesity.

Interaction effects between childhood emotional overeating and polygenic influences on pubertal timing and tempo / 中国学校卫生

Objective@#To explore the interaction effects and possible sex differences in childhood emotional overeating and polygenic influences on adolescent pubertal timing and tempo.@*Methods@#In March 2016 (T0), all participants were recruited from grades 1 to 3 from two primary school of Bengbu, Anhui Province using cluster sampling, and follow up surveys were conducted once per year (T1, T2, T3). Emotional overeating was assessed at T1 and pubertal development was assessed annually (breast Tanner stage in girls and testicular volume in boys). The nonlinear growth model was used to estimate pubertal timing and tempo. Polygenic risk scores were calculated based on 17 SNPs for early pubertal timing. Hierarchical linear regression was performed to examine the interaction effects between childhood emotional overeating and polygenic risk scores on pubertal timing and tempo.@*Results@#The complete data of 896 children were analyzed, including 373 boys (41.60%) and 523 girls (58.40%). A total of 203 (22.7%) children reported emotional overeating behavior at T1. After adjusting for several variables including early life adversity, delivery mode, and birthweight, only emotional overeating was associated with accelerated pubertal tempo among girls with a high genetic risk (B=0.19, 95%CI=0.07~0.32， P<0.01), although there was no association with pubertal timing (B=0.14, 95%CI=-0.12~0.41，P=0.28). In girls with a low genetic risk and boys, no evidence was found to support interaction effects between childhood emotional overeating and polygenic influences on pubertal timing and tempo (P＞0.05).@*Conclusion@#Emotional overeating was associated with a faster pubertal tempo in girls who had a high genetic risk of early pubertal development.

Improving the yield of Anoectochilus roxburghii by Bacillus licheniformis cultured in Agaricus bisporus industrial wastewater

BACKGROUND: There is a large amount of industrial wastewater produced by the mushroom industry during the canning processing each year, which could provide abundant carbon, nitrogen and inorganic salts for microbial growth. The aim of this study was to optimize the culture conditions for Bacillus licheniformis cultured in the Agaricus bisporus industrial wastewater to produce the agricultural microbial fertilizer. RESULTS: In this work, the maximal biomass of B. licheniformis could be obtained under the following culture conditions: 33.7°C, pH 7.0, 221 rpm shaking speed, 0.5% wastewater, 2 (v:v, %) inoculum dose, loading liquid of 60 mL/250 mL and a culture time of 24 h, and the average experimental value obtained was 1.35 ± 0.04 × 109 Obj/mL, which was within the 95% confidence interval of the predicted model (1.29­1.38 × 109 Obj/mL), and met the national microbial fertilizers' standard in China. Furthermore, the field experiment results showed that the fermentation broth of B. licheniformis could significantly improve the yield of Anoectochilus roxburghii. CONCLUSIONS: Agaricus bisporus industrial wastewater can be used to produce agricultural microbial fertilizer.

A boundary element method based near field acoustic holography in noisy environments.

In noisy environments, the acoustic wave is complicated and consists of the radiated wave, the incident wave, as well as its scattering wave. Double-layered pressure measurement is introduced to the boundary element method based near field acoustic holography to recover the free field quantities. First, the incoming and outgoing propagation waves are separated by exploring the propagation property of the two waves from their source to the field with the boundary integral equation. Subsequently, the scattering wave is filtered out by considering the boundary condition of the vibrating structure. Further, a measurement on an enclosing hologram is adopted to accurately reconstruct the distribution of normal velocity on the boundary. Two sets of the system of linear equations are built on the double-layered measurements. The Schur complement equation is then applied in conjunction with the Tikhonov regularization method to obtain an optimized reconstruction. Numerical examples are set up for two representative radiators impinged by incident waves. It is demonstrated that the free field normal velocity can be correctly reconstructed even if the signal-to-noise ratio is negative. An experiment is conducted for the cubic radiator to verify the accuracy and potential for the practical reconstruction in a noisy environment.

Beamforming correction for the singular problem in identifying rotating sources with non-uniform directivity.

Identification of rotating sources with non-uniform directivity has been paid much attention in the field of aeroacoustic measurements over recent years. Singularities may be produced on the source map by using the rotating source identifier based on the multipole model due to zeros of the directivity function. A correction method is proposed to remove the influence of source directivity on source imaging and restrain the singular problem. De-Dopplerized microphone signals are transformed to the frequency domain and deconvolved with transfer functions to compensate for directivity functions. Numerical simulations, as well as experiments using rotating dipole loudspeakers, were conducted to verify the proposed method. It is demonstrated that the method is suitable for rotating sources with arbitrary orientation and works well under a high level of background noise. Positions and strengths of sources are estimated more accurately than traditional algorithms.

Dipole-based beamforming method for locating dipole sources with unknown orientations in three-dimensional domains.

In conventional delay-and-sum beamforming, the monopole source assumption may cause a dipole source to be misinterpreted, leading to incorrect mapping results. A dipole-based beamforming method is proposed that is an extension of monopole-based conventional beamforming. The dipole sources could be located with no prior knowledge of the source orientation, and the unknown orientation is arbitrary in a three-dimensional domain. The location of a dipole source is determined by calculating the beamforming results at predefined orientations and positions using a dipole-based propagation function, and the final beamforming result at each scanning point is determined by the maximum value at the predefined orientations. Numerical simulations and experiments are performed on rotating dipole sources, and satisfactory results for the location of these dipole sources are obtained with different orientations.

Acoustic spatial patterns recognition based on convolutional neural network and acoustic visualization.

In this work, a convolutional neural network (CNN) is applied to recognize acoustic spatial patterns with the aid of acoustic visualization. The acoustic spatial patterns are obtained by the singular value decomposition of an acoustic radiation operator built with the boundary integral equation. It is to explore the powerful capability of the CNN in the image processing by analogously rendering the measured acoustic spatial patterns into images. Due to practical limitations, a higher resolution of an acoustic image is achieved by interpolating the pressure on a coarse grid. Steady-state analysis of acoustic problems is a complex domain problem. The acoustic fields are then supplied into a CNN scheme as two-channel data which are real and imaginary components of the pressure. Random noises and incident waves with varying energy are added to the measured data to simulate influences from uncorrelated and correlated noises, respectively. It is demonstrated that once the CNN scheme is built and trained with adequate data, which is numerically synthesized, the patterns can be more accurately and robustly recognized by comparing it with the cross-correlation based methods. The hierarchical feature representative as well as nonlinear perception makes the proposed method a promising approach for fault diagnosis and condition monitoring based on spatial acoustic measurements.