Direct Observation of Covalently Bound Clusters in Resonantly Stabilized Radical Reactions and Implications for Carbonaceous Particle Growth.

Based on quantum mechanically guided experiments that observed elusive intermediates in the domain of inception that lies between large molecules and soot particles, we provide a new mechanism for the formation of carbonaceous particles from gas-phase molecular precursors. We investigated the clustering behavior of resonantly stabilized radicals (RSRs) and their interactions with unsaturated hydrocarbons through a combination of gas-phase reaction experiments and theoretical calculations. Our research directly observed a sequence of covalently bound clusters (CBCs) as key intermediates in the evolution from small RSRs, such as benzyl (C7H7), indenyl (C9H7), 1-methylnaphthyl (1-C11H9), and 2-methylnaphthyl (2-C11H9), to large polycyclic aromatic hydrocarbons (PAHs) consisting of 28 to 55 carbons. We found that hydrogen abstraction and RSR addition drive the formation and growth of CBCs, leading to progressive H-losses, the generation of large PAHs and PAH radicals, and the formation of white smoke (incipient carbonaceous particles). This mechanism of progressive H-losses from CBCs (PHLCBC) elucidates the crucial relationship among RSRs, CBCs, and PAHs, and this study provides an unprecedentedly seamless path of observed assembly from small RSRs to large nanoparticles. Understanding the PHLCBC mechanism over a wide temperature range may enhance the accuracy of multiscale models of soot formation, guide the synthesis of carbonaceous nanomaterials, and deepen our understanding of the origin and evolution of carbon within our galaxy.

A Self-Powered Lactate Sensor Based on the Piezoelectric Effect for Assessing Tumor Development.

The build-up of lactate in solid tumors stands as a crucial and early occurrence in malignancy development, and the concentration of lactate in the tumor microenvironment may be a more sensitive indicator for analyzing primary tumors. In this study, we designed a self-powered lactate sensor for the rapid analysis of tumor samples, utilizing the coupling between the piezoelectric effect and enzymatic reaction. This lactate sensor is fabricated using a ZnO nanowire array modified with lactate oxidase (LOx). The sensing process does not require an external power source or batteries. The device can directly output electric signals containing lactate concentration information when subjected to external forces. The lactate concentration detection upper limit of the sensor is at least 27 mM, with a limit of detection (LOD) of approximately 1.3 mM and a response time of around 10 s. This study innovatively applied self-powered technology to the in situ detection of the tumor microenvironment and used the results to estimate the growth period of the primary tumor. The availability of this application has been confirmed through biological experiments. Furthermore, the sensor data generated by the device offer valuable insights for evaluating the likelihood of remote tumor metastasis. This study may expand the research scope of self-powered technology in the field of medical diagnosis and offer a novel perspective on cancer diagnosis.

Preparation of Flower-like Nanosilver Based on Bioderived Caffeic Acid for Raman Enhancement and Dye Degradation.

In this study, a simple, green, and low-cost room temperature synthesis of broccoli-like silver nanoflowers (AgNF) with a particle size of about 300-500 nm was developed using plant-derived caffeic acid as a reducing agent and polyvinylpyrrolidone as a dispersant under ultrasound assistance. The flower clusters covered by small nanocrystals of 20-50 nm significantly enhance the electromagnetic field signals. AgNF was deposited on the surface of silicon wafers as a surface-enhanced Raman spectroscopy sensor for the detection of probe molecules such as rhodamine 6G (R6G) and malachite green with high sensitivity, homogeneity, and reproducibility. AgNF was deposited on cotton fabrics in the form of composites to catalyze the degradation of dye pollutants such as R6G, MG, and methyl orange in the presence of sodium borohydride. 0.1 g of AgNF/cotton fabric could assist 15 mmol/L NaBH4 to achieve over 90% degradation of various dyes as well as a high concentration of dyes in 12 min with good reusability and recyclability. The AgNF synthesized in this work can not only monitor the type and amounts of pollutants (dyes) in wastewater but also catalyze the rapid degradation of dyes, which is expected to be valuable for industrial applications.

More than a colour; how pigment influences colourblind microbes.

Many animals have pigments when they themselves cannot see colour. Perhaps those pigments enable the animal to avoid predators, or to attract mates. Maybe even those pigmented surfaces are hosts for microbes, even when the microbes do not see colour. Do some pigments then serve as a chemical signal for a good or bad microbial substrate? Maybe pigments attract or repel various microbe types? Echinoderms serve as an important model to test the mechanisms of pigment-based microbial interactions. Echinoderms are marine benthic organisms, ranging from intertidal habitats to depths of thousands of metres and are exposed to large varieties of microbes. They are also highly pigmented, with a diverse variety of colours between and even within species. Here we focus on one type of pigment (naphthoquinones) made by polyketide synthase, modified by flavin-dependent monoxygenases, and on one type of function, microbial interaction. Recent successes in targeted gene inactivation by CRISPR/Cas9 in sea urchins supports the contention that colour is more than it seems. Here we dissect the players, and their interactions to better understand how such host factors influence a microbial colonization. This article is part of the theme issue 'Sculpting the microbiome: how host factors determine and respond to microbial colonization'.

Preparation of polyphenol-structural colored silk fabrics with bright colors.

Conventional textile dyeing relies on the use of dyes and pigments, which can cause severe environmental contamination and waste a large amount of water. Structural coloring is one of the effective ways to achieve environmentally friendly coloring of textiles. In this work, three plant polyphenols with the same o-benzenetriol structure (tannic acid (TA), gallic acid (GA), and tea polyphenol (TP)) were selected as raw materials. Three plant polyphenols can quickly form nanofilms at the gas-liquid interface through a Schiff base reaction with polyethyleneimine (PEI) under mildly alkaline conditions, which were deposited to the surface of silk fabric, allowing precise control over the thickness of film by adjusting the time, resulting in various structurally colored silk fabric. This method for creating structural colors is not substrate-specific and enables the quick production of structural colors on various textile substrates. Furthermore, the structural color silk fabric based on plant polyphenol has antibacterial performance. This textile coloring method is simple, cost-effective and environmentally friendly, providing a new approach to eco-friendly textile dyeing.

A wireless battery-free eye modulation patch for high myopia therapy.

The proper axial length of the eye is crucial for achieving emmetropia. In this study, we present a wireless battery-free eye modulation patch designed to correct high myopia and prevent relapse. The patch consists of piezoelectric transducers, an electrochemical micro-actuator, a drug microneedle array, µ-LEDs, a flexible circuit, and biocompatible encapsulation. The system can be wirelessly powered and controlled using external ultrasound. The electrochemical micro-actuator plays a key role in precisely shortening the axial length by driving the posterior sclera inward. This ensures accurate scene imaging on the retina for myopia eye. The drug microneedle array delivers riboflavin to the posterior sclera, and µ-LEDs' blue light induces collagen cross-linking, reinforcing sclera strength. In vivo experiments demonstrate that the patch successfully reduces the rabbit eye's axial length by ~1217 µm and increases sclera strength by 387%. The system operates effectively within the body without the need for batteries. Here, we show that the patch offers a promising avenue for clinically treating high myopia.

Microbial diversity of ticks and a novel typhus group Rickettsia species (Rickettsiales bacterium Ac37b) in Inner Mongolia, China.

Ticks can carry multiple pathogens, and Inner Mongolia's animal husbandry provides excellent environmental conditions for ticks. This study characterized the microbiome of ticks from different geographical locations in Inner Mongolia; 905 Dermacentor nuttalli and 36 Ixodes persulcatus were collected from sheep in three main pasture areas and from bushes within the forested area. Mixed DNA samples were prepared from three specimens from each region and tick species. Microbial diversity was analyzed by 16S rRNA sequencing, and α and ß diversity were determined. The predominant bacterial genera were Rickettsia (54.60%), including Rickettsiales bacterium Ac37b (19.33%) and other Rickettsia (35.27%), Arsenophonus (11.21%), Candidatus Lariskella (10.84%), and Acinetobacter (7.17%). Rickettsia bellii was identified in I. persulcatus, while Rickettsiales bacterium Ac37b was found in D. nuttalli from Ordos and Chifeng. Potential Rickettsia and Anaplasma coinfections were observed in the Ordos region. Tick microbial diversity analysis in Inner Mongolia suggests that sheep at the sampling sites were exposed to multiple pathogens.

Title: Diversité microbienne des tiques et nouvelle espèce de Rickettsia du groupe du typhus (bactérie Rickettsiales Ac37b) en Mongolie intérieure, Chine. Abstract: Les tiques peuvent être porteuses de plusieurs agents pathogènes et l'élevage en Mongolie intérieure offre d'excellentes conditions environnementales pour les tiques. Cette étude a caractérisé le microbiome des tiques de différentes zones géographiques de Mongolie intérieure; 905 Dermacentor nuttalli et 36 Ixodes persulcatus ont été collectés sur des moutons dans trois principales zones de pâturage et dans des buissons de la zone forestière. Des échantillons d'ADN mixtes ont été préparés à partir de trois spécimens de chaque région et espèce de tique. La diversité microbienne a été analysée par séquençage de l'ARNr 16S et la diversité α et ß a été déterminée. Les genres bactériens prédominants étaient les Rickettsia (54,60 %), dont la bactérie Rickettsiales Ac37b (19,33 %) et d'autres Rickettsia (35,27 %), Arsenophonus (11,21 %), Candidatus Lariskella (10,84 %) et Acinetobacter (7,17 %). Rickettsia bellii a été identifiée chez I. persulcatus, tandis que la bactérie Rickettsiales Ac37b a été trouvée chez D. nuttalli d'Ordos et Chifeng. Des co-infections potentielles à Rickettsia et Anaplasma ont été observées dans la région d'Ordos. L'analyse de la diversité microbienne des tiques en Mongolie intérieure montre que les moutons présents sur les sites d'échantillonnage sont exposés à plusieurs agents pathogènes.

Preparation of Superhydrophobic Fabric Based on Dopamine and Michael Addition under Ultraviolet Light.

This work reports a simple, stable, and environmentally friendly method to prepare durable superhydrophobic surfaces. First, a polydopamine coating is formed by oxidative polymerization of dopamine to form a secondary reaction platform to provide reaction sites for subsequent experiments. We applied a polydopamine layer onto a fiber surface using the Michael addition-reaction-grafted tetrakis (3-mercaptopropionic acid) pentaerythritol ester, followed by the introduction of tetraallyl silane and (mercapto) methyl siloxane-dimethyl siloxane copolymer on the polydopamine by a thiol-ene click-reaction under ultraviolet light. The resulting superhydrophobic Nylon 56 fabric exhibited a 166° static contact angle as well as excellent stability. The surface morphology of all samples was observed by field emission scanning electron microscope, X-ray photoelectron spectroscopy and energy dispersion spectroscopy, and the elemental composition and surface chemical state of the samples were analyzed. It also had the ability of oil-water separation. Fabric with such benefits broadens the applicability and innovation of superhydrophobic textiles for environmental and industrial applications.

Implanted, Wireless, Self-Powered Photodynamic Therapeutic Tablet Synergizes with Ferroptosis Inducer for Effective Cancer Treatment.

The effective and targeted treatment of resistant cancer cells presents a significant challenge. Targeting cell ferroptosis has shown remarkable efficacy against apoptosis-resistant tumors due to their elevated iron metabolism and oxidative stress levels. However, various obstacles have limited its effectiveness. To overcome these challenges and enhance ferroptosis in cancer cells, we have developed a self-powered photodynamic therapeutic tablet that integrates a ferroptosis inducer (FIN), imidazole ketone erastin (IKE). FINs augment the sensitivity of photodynamic therapy (PDT) by increasing oxidative stress and lipid peroxidation. Furthermore, they utilize the Fenton reaction to supplement oxygen, generating a greater amount of reactive oxygen species (ROS) during PDT. Additionally, PDT facilitates the release of iron ions from the labile iron pool (LIP), accelerating lipid peroxidation and inducing ferroptosis. In vitro and in vivo experiments have demonstrated a more than 85% tumor inhibition rate. This synergistic treatment approach not only addresses the limitations of inadequate penetration and tumor hypoxia associated with PDT but also reduces the required medication dosage. Its high efficiency and specificity towards targeted cells minimize adverse effects, presenting a novel approach to combat clinical resistance in cancer treatment.

Effects of Using Sitting Position versus Lithotomy Position during the Second Stage of Labour on Maternal and Neonatal Outcomes and the Childbirth Experience of Chinese Women: A Prospective Cohort Study.

Existing research concerning the effects of the sitting birth position during the second stage of labour on maternal and neonatal outcomes remains controversial, and there is a lack of studies to explore its effect on the childbirth experience. The objective of this study is to explore whether the sitting birth position would influence maternal and neonatal outcomes, as well as the childbirth experience. The prospective cohort design was conducted in the study from February to June 2023, a total of 222 women (including primiparous women and multiparous women) were enrolled in our study, and they were divided into the sitting position cohort (n = 106) or the lithotomy position cohort (n = 116). The pre-designed questionnaire and Childbirth Experience Questionnaire (CEQ) were used for data collection during hospitalisation. Chi-square, Fisher's exact test, t-tests, or the Mann-Whitney U test were utilised to assess differences between groups. Multivariate linear regression and logistic regression were employed to control possible confounders. The study found that primiparous women in the sitting position cohort had a shorter duration of the second stage of labour, higher spontaneous vaginal birth rates, lower episiotomy rates, and a better childbirth experience (p < 0.01). After adjusting for confounding factors through multiple linear and logistic regression analyses, the results remained consistent with those reported above. No neonate in each cohort had Apgar scores at 1 min and 5 min postpartum less than 7 or a Cord artery pH less than 7.00, regardless of parity. Based on the findings, we recommend that women could take the sitting birth position into account when giving birth for a positive childbirth experience, especially for primiparous women. The study could also serve as a reference for healthcare providers in the management of childbirth positions and the development of high-quality maternal care.

Theoretical Kinetic Study on Hydrogen Abstraction Reactions from n-Pentane by NO2.

The interaction of fuel with NOx chemistry is important for the construction of the reaction mechanism and engine application. In this work, the reaction pathways of nC5H12 + NO2 were studied by high-level electronic structure calculations (DLPNO-CCSD(T)-F12/cc-pVTZ-F12//B2PLYPD3/cc-pVTZ). The rate constants were calculated by using the multistructural canonical transition-state theory with the Eckart tunneling method (TST/MS-T/ET). The studied condition is in a wide temperature range of 298-2400 K. The influence of MS-T anharmonicity and tunneling effect will be clarified for these site-specific H-abstraction pathways. The result reflects the large deviation introduced by the treatment of MS-T anharmonicity, especially at a high temperature. For the same type of reactions, the rate constants of H-abstraction both occurring at the secondary carbon are not almost identical. The branching ratios show that abstraction from the secondary site forming cis-HONO (R2c) contributes 36-78% to nC5H12 consumption in the temperature range of 298-2400 K. The current results show that the multistructural torsional anharmonicity has a crucial influence on the accurate estimation of branching ratios.

The management framework of upright position in the second stage of labour: A qualitative study.

BACKGROUND: Upright positions, as a non-pharmacological, have been well documented in multiple studies to promote normal labor, facilitate favourable birth outcomes and positive childbirth experience. Yet, the application status of upright positions in China, and even globally, is unfavourable. Thus, we have developed the Program for Upright Positions in the Second Stage of Labor (UPSSL program) for the widespread application of upright positions. While there is limited research evidence on the areas of improvement and corresponding strategies for embedding the evidence into midwifery practice. OBJECTIVES: To explore perspectives of health care providers on improvement areas of upright positions in the second stage of labor, and to identify corresponding strategies in order to develop a management framework for successful implementation of upright positions. METHODS: A qualitative descriptive design with semi-structured interviews was conducted in the study. The participants involving 13 midwives, six obstetricians and six department managers were selected from three hospitals in Beijing, China. ATLAS.TI 8 software was utilized to manage, identify the transcript data, and the thematic analysis method guided the data analysis. RESULTS: A management framework of upright positions in the second stage of labor was developed based on our study, which included five improvement areas : (1) promoting the renewal of midwifery notions and the professional training;(2) strengthening maternal health education based on the "trinity" approach; (3) promoting multidisciplinary cooperation and refining the labor procedures in upright positions; (4) optimizing midwifery human resource allocation and formulating incentive policies; (5) encouraging partner involvement and improving the birth environment. CONCLUSIONS: The study findings could provide a comprehensive view to promote UPSSL Program to be utilized in practice. Our study also provided a way for midwives, obstetricians, and other healthcare providers to work together to facilitate high quality maternal care. IMPLICATIONS FOR PRACTICE: Our findings will be useful for nursing managers to carry out the UPSSL program through several strategies, such as strengthening the professional training for assisting labor in the upright positions, reallocating midwifery human resources, and developing the childbirth education on the upright positions.

[Research progress of platelet bacteriostatic effects].

Platelets not only have hemostatic function, but can also directly or indirectly recognize pathogenic microorganisms and the signals they produce to capture and destroy them through membrane receptors. They can collaborate with various components of the body's immune system by releasing of intraplatelet particulate matter, cytokines and chemokines to perform bactericidal functions. And it can also play a bactericidal role by swallowing pathogens, releasing antimicrobial proteins and chemokines and activating and enhancing other specialized anti-inflammatory cells bactericidal effect, such as leukocytes and so on. However, the bacteriostatic composition and bacteriostatic mechanism of platelets remain unclear, so attention should be paid to the immune mechanism and bacteriostatic effect of platelets.

Implementation of the Practice Programme for Upright Positions in the Second Stage of Labour and the birth experience of Chinese women: A qualitative study.

OBJECTIVE: Upright positions in the second stage of labour are recommended by many international organizations. However, they have not been widely used worldwide, especially in China. One of the important factors is the absence of a practice programme based on the best available evidence. We thus developed a Practice Programme for Upright Positions in the Second Stage of Labour following the UK Medical Research Council framework. Under the guidance of the programme, whether the use of upright positions can improve the maternal birth experience is a question of great concern. This study aimed to explore the birth experience of Chinese women who adopted upright positions in the second stage of labour. DESIGN: This qualitative descriptive study was conducted as part of an implementation study that developed an evidence-based intervention and used strategies to integrate the evidence-based intervention into routine obstetric clinical practice. SETTING: The maternity department of a tertiary comprehensive hospital in Hebei Province, China. PARTICIPANTS: Semi-structured interviews with twelve eligible women who adopted upright positions in the second stage of labour were conducted between March and April 2022. Qualitative data were analyzed by using conventional content analysis. FINDINGS: The average age of included women was 26.5 ± 3.5 years, and ten of them were primiparous women. Eight women adopted epidural analgesia during labour to relieve labour pain. All women gave birth in at least one type of upright position in the passive second stage of labour and adopted the semi-recumbent position in the active second stage of labour. Through conventional content analysis, we found that the use of upright positions in the second stage of labour could possibly promote an overall positive birth experience. Women giving birth in upright positions generally perceived they were more involved in their birthing process, and had greater physical and mental capacity to cope with childbirth. KEY CONCLUSIONS: Women have a positive birth experience when using upright positions in the second stage of labour. IMPLICATIONS FOR PRACTICE: This study suggests upright positions could improve women's birth experience and have the potential to be widely applied in clinical practice.

Single-Cell Transcriptome and Pigment Biochemistry Analysis Reveals the Potential for the High Nutritional and Medicinal Value of Purple Sea Cucumbers.

The sea cucumber Apostichopus japonicus has important nutritional and medicinal value. Unfortunately, we know little of the source of active chemicals in this animal, but the plentiful pigments of these animals are thought to function in intriguing ways for translation into clinical and food chemistry usage. Here, we found key cell groups with the gene activity predicted for the color morphology of sea cucumber body using single-cell RNA-seq. We refer to these cell populations as melanocytes and quinocytes, which are responsible for the synthesis of melanin and quinone pigments, respectively. We integrated analysis of pigment biochemistry with the transcript profiles to illuminate the molecular mechanisms regulating distinct pigment formation in echinoderms. In concert with the correlated pigment analysis from each color morph, this study expands our understanding of medically important pigment production, as well as the genetic mechanisms for color morphs, and provides deep datasets for exploring advancements in the fields of bioactives and nutraceuticals.

Robust and flexible smart silk/PEDOT conductive fibers as wearable sensor for personal health management and information transmission.

Flexible highly conductive fibers have attracted much attention due to their great potential in the field of wearable electronic devices. In this work, silk/PEDOT conductive fibers with a resistivity of 1.73 Ω·cm were obtained by oxidizing Ce3+ with H2O2 under alkaline conditions to produce CeO2 and further promote the in-situ polymerization of 3,4-ethylenedioxythiophene (EDOT) on the surface of silk fibers. The morphology and chemical composition of the silk/PEDOT conductive fibers were characterized and the results confirmed that a large amount of polythiophene was synthesized and deposited on the surface of silk fibers. The conductivity and electrochemical property stability of the silk/PEDOT conductive fibers were evaluated by soaping and organic solvent immersion, and the conductive silk fibers exhibited excellent environmental stability and durability. The silk/PEDOT conductive fibers show good pressure sensing and strain sensing performance, which exhibits high sensitivity, fast response and cyclability, and have excellent applications in personal health monitoring, human-machine information transmission, etc.

Study on the Effect of Chitosan Modification Technology on Antibacterial Properties of Textiles.

The chitosan is fixed in an amide group of activated carboxyl groups and biological primary amino groups of nonwoven PET for antibacterial properties. Uncoated materials have fewer wetting properties and are less biocompatible. The objectives of the study were to evaluate surface chemical compositions and biocompatibility, antibacterial, and hydrophilic properties of polyester fabrics grafted with chitosan oligomers and after being activated by atmospheric pressure plasmas. A 2% 14.8 mg/cm2 uncolored PET woven fabric was dissolved in chitosan solution. Atmospheric pressure plasmas were used to activate polyester fabrics grafted with chitosan oligomers on both sides. Cell proliferation assay was performed for the biocompatibility study. The American Association of Textile Chemists and Colorists method was used to measure the width of the antibacterial zone and the Japanese Industrial Standard was used to count the number of bacterial colonies. Chitosan-coated and -activated uncolored PET woven fabric showed fewer percentage free carbon (p < 0.0001), higher percentage free oxygen to free carbon ratio (p < 0.0001), higher percentage free nitrogen to free carbon ratio (p = 0.0453), and higher percentage free oxygen plus free nitrogen to free carbon ratio (p < 0.0001) than untreated PET woven fabric. The dynamic contact angle of a water droplet and the wicking time were shorter for chitosan-coated and -activated uncolored PET woven fabric than untreated PET weaved fabric (p < 0.0001 for all). Chitosan coating leads to PET woven fabric being higher biocompatible, wettable, and antibacterial than untreated PET woven fabric.

Effect of Cu loading on the performance and kinetics of Cu/SAPO-34 catalysts for selective catalytic reduction with NH3.

A series of X%Cu/SAPO-34 (X = 1.0, 2.0, 4.0 and 6.0) catalysts were prepared by ultrasonic impregnation method for selective catalytic reduction (SCR) of NOx with ammonia. The effect of different Cu loadings on the selective catalytic reduction of NO by molecular sieve catalysts was examined on a fixed-bed reactor. Catalyst physicochemical properties were characterized and analyzed using XRD, TEM, NH3-TPD, H2-TPR, and in situ DRIFTS. Catalysts were used in reaction kinetics studies from the perspective of transient and steady-state kinetics. Cu/SAPO-34 catalyst with 4% Cu loading had the best denitrification efficiency and wide activity window. Copper species were highly dispersed on the catalyst surface. Cu/SAPO-34 catalyst with 4% Cu loading had rich acidic sites and excellent redox performance. Cu/SAPO-34 catalysts with 4% Cu loading possess minimal activation energy and were lower than commercial catalysts. According to the results of in situ IR, transient and steady-state analysis, the Cu/SAPO-34 catalyst with 4% Cu loading in the NH3-SCR reaction process was mainly E-R mechanism, and there was L-H mechanism.

The Resistance of SO2 and H2O of Mn-Based Catalysts for NO x Selective Catalytic Reduction with Ammonia: Recent Advances and Perspectives.

The treatment of NO x has become an urgent issue due to it being difficult to degrade in air and its tremendous adverse impact on public health. Among numerous NO x emission control technologies, the technology of selective catalytic reduction (SCR) using ammonia (NH3) as the reducing agent (NH3-SCR) is regarded as the most effective and promising technique. However, the development and application of high-efficiency catalysts is severely limited due to the poisoning and deactivation effect by SO2 and H2O vapor in the low-temperature NH3-SCR technology. In this review, recent advances in the catalytic effects from increasing the rate of the activity in low-temperature NH3-SCR by manganese-based catalysts and the stability of resistance to H2O and SO2 during catalytic denitration are reviewed. In addition, the denitration reaction mechanism, metal modification, preparation methods, and structures of the catalyst are highlighted, and the challenges and potential solutions for the design of a catalytic system for degenerating NO x over Mn-based catalysts with high resistance of SO2 and H2O are discussed in detail.

A self-powered sound-driven humidity sensor for wearable intelligent dehydration monitoring system.

Self-powered wearable sensing systems have attracted great attention for their application in continuous health monitoring, which can reveal real-time physiological information on the body. Here, an innovative self-powered sound-driven humidity sensor for wearable intelligent dehydration monitoring system has been proposed. The sensor is primarily comprised of PTFE membrane, ZnO nanoarrays and Ti thin film. The piezoelectric/triboelectric effect of ZnO nanoarrays/PTFE membrane is coupled with the humidity sensing process. Sound wave can drive PTFE membrane to vibrate, and the contact and separation between PTFE and ZnO can generate electrical signals through piezoelectric/triboelectric effect. At the same time, the surface of the nanostructures can absorb the water molecules, which will influence the electrical output of the device. The device can convert sound energy into electrical output without any external electricity power supply, and the outputting voltage decreases with increasing relative humidity, acting as the sensing signal. The sensor has been integrated with data processing unit and wireless transmission module to form a self-powered wearable intelligent dehydration monitoring system, which can actively monitor the humidity of exhaled breath and transmit the information to the mobile phone. The results can open a possible new direction for the development of sound-driven gas sensors and will further expand the scope for self-powered nanosystems.