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1.
J Environ Sci (China) ; 149: 394-405, 2025 Mar.
Article de Anglais | MEDLINE | ID: mdl-39181652

RÉSUMÉ

Heterogeneous crystallization is a common occurrence during the formation of solid wastes. It leads to the encapsulation of valuable/hazardous metals within the primary phase, presenting significant challenges for waste treatment and metal recovery. Herein, we proposed a novel method involving the in-situ formation of a competitive substrate during the precipitation of jarosite waste, which is an essential process for removing iron in zinc hydrometallurgy. We observed that the in-situ-formed competitive substrate effectively inhibits the heterogeneous crystallization of jarosite on the surface of anglesite, a lead-rich phase present in the jarosite waste. As a result, the iron content on the anglesite surface decreases from 34.8% to 1.65%. The competitive substrate was identified as schwertmannite, characterized by its loose structure and large surface area. Furthermore, we have elucidated a novel mechanism underlying this inhibition of heterogeneous crystallization, which involves the local supersaturation of jarosite caused by the release of ferric and sulfate ions from the competitive substrate. The local supersaturation promotes the preferential heterogeneous crystallization of jarosite on the competitive substrate. Interestingly, during the formation of jarosite, the competitive substrate gradually vanished through a dissolution-recrystallization process following the Ostwald rule, where a metastable phase slowly transitions to a stable phase. This effectively precluded the introduction of impurities and reduced waste volume. The goal of this study is to provide fresh insights into the mechanism of heterogeneous crystallization control, and to offer practical crystallization strategies conducive to metal separation and recovery from solid waste in industries.


Sujet(s)
Cristallisation , Composés du fer III , Composés du fer III/composition chimique , Sulfates/composition chimique , Composés du fer/composition chimique , Fer/composition chimique , Élimination des déchets/méthodes
2.
Front Pediatr ; 12: 1455171, 2024.
Article de Anglais | MEDLINE | ID: mdl-39233869

RÉSUMÉ

Background: Lower urinary tract symptoms (LUTS) are clinically frequent and seriously affect the psychological and mental health of children and adolescents. However, most studies on LUTS and its influence on the psychological behavior and mental health have focused on adults. This study aimed to investigate LUTS prevalence and associated factors in children and adolescents and explore its impact on psychological behavior. Materials and methods: From October 2019 to November 2021, an epidemiological LUTS survey was carried out on 6,077 children aged 6-15 years old in 12 primary and secondary schools in China by using anonymous questionnaires. Results: A total of 5,500 valid questionnaires were collected, and the total prevalence of four representative symptoms of LUTS: urgency, frequency, daytime urinary incontinence, and nocturnal enuresis was 19.46%, 14.55%, 9.75%, and 8.4%, respectively. The prevalence decreased with age, which decreased rapidly in children aged 6-12 years old. The incidence of LUTS in those who did not continue to use disposable diapers (DD) and began to perform elimination communication (EC) after the age of 1 was significantly higher than that of those who stopped using DD and started EC before 1 year of age (P < 0.05). There were significant differences in the occurrence of LUTS without toiled training (TT) (P < 0.05). The prevalence of LUTS in males was significantly higher than in females (P < 0.05). LUTS in children and adolescents with constipation was significantly higher compared to those without constipation (P < 0.05). The detection rate of abnormal psychological behavior in the LUTS group was 44.6%, which was significantly higher than that in the no LUTS group (21.4%, P < 0.05). The scores of emotional symptoms, conduct problems, hyperactivity, and peer communication problems were significantly higher in the LUTS group than the control group. Conclusions: In Mainland China, the prevalence of LUTS in children and adolescents is high. Continued use of DD after 1 year of age, history of urinary tract infection, lack of TT, and constipation were risk factors for LUTS. EC before 1 year of age is a protective factor for LUTS. The prevalence of psychological behavioral abnormalities is high in children and adolescents with LUTS, which needs to be more concerned.

3.
Neurourol Urodyn ; 2024 Sep 05.
Article de Anglais | MEDLINE | ID: mdl-39234771

RÉSUMÉ

AIM: Sacral neuromodulation (SNM) is widely recognized as the essential treatment modality for patients suffering from various lower urinary tract disorders, particularly overactive bladder (OAB). This prospective study recruited patients who underwent variable frequency SNM treatment at six Chinese medical centers, aiming to evaluate the gender-specific effects of this intervention and provide precise guidance on its application for clinical management. METHODS: This prospective study was managed by Beijing Hospital, and six Chinese medical centers participated in this prospective research. Inclusion and exclusion criteria were established to screen patients based on the indication for SNM. During the research, all patients were required to record 72-h voiding diaries, urgency scores, and visual analogue scale (VAS) scores to reflect their disease symptoms. Additionally, subjective questionnaire surveys such as OAB symptom score (OABSS) and quality-of-life (Qol) score were recorded to reflect the patients' quality of life and treatment satisfaction. RESULTS: In this study, 52 patients (male patients: 25; female patients: 27) with OAB symptoms agreed to undergo variable frequency stimulation SNM therapy and finally convert to Stage II. Regarding the baseline outcomes, no significant differences were observed between the male and female groups. In terms of postoperative indicators, male patients showed a greater improvement in Qol scores compared to their female counterparts (20.06 ± 13.12 vs. 40.83 ± 26.06, p = 0.005). The results from VAS scores indicated that pain remission was more pronounced in male patients than in female patients (0.31 ± 0.87 vs. 1.67 ± 2.16, p = 0.02). Importantly, there was a statistically significant disparity in urinary urgency between males and females (male patients: 1.19 ± 1.56; female patients: 2.17 ± 1.52, p = 0.04). CONCLUSIONS: In our study, we found that variable frequency SNM treatment yielded sex-specific differences in therapeutic effects, with male patients having a better outcome in some metrics. This suggests that a patient's sex may influence when variable frequency SNM is used, and in the patient's follow-up. TRIAL REGISTRATION: ClinicalTrials.gov identifier: ChiCTR2000036677.

4.
Biochem Biophys Res Commun ; 734: 150633, 2024 Aug 31.
Article de Anglais | MEDLINE | ID: mdl-39243678

RÉSUMÉ

The study aimed to develop a prognostic model for Hepatocellular Carcinoma (HCC) based on pan-apoptosis-related genes, a novel inflammatory programmed cell death form intricately linked to HCC progression. Utilizing transcriptome sequencing and clinical data from the TCGA database, we identified six crucial pan-apoptosis-related genes through statistical analyses. These genes were then employed to construct a prognostic model that accurately predicts overall survival rates in HCC patients. Our findings revealed a strong correlation between the model's risk scores and tumor microenvironment (TME) status, immune cell infiltration, and immune checkpoint expression. Furthermore, we screened for drugs with potential therapeutic efficacy in high- and low-risk HCC groups. Notably, PPP2R5B gene knockdown was found to inhibit HCC cell proliferation and clonogenic capacity, suggesting its role in HCC progression. In conclusion, this study presents a novel pan-apoptosis gene-based prognostic risk model for HCC, providing valuable insights into patient TME status and guiding the selection of targeted therapies and immunotherapies.

5.
J Pediatr Urol ; 2024 Jul 16.
Article de Anglais | MEDLINE | ID: mdl-39097491

RÉSUMÉ

INTRODUCTION: Overactive bladder (OAB) in children is clinically common and seriously affects the physical and mental health of children. The voiding frequency (VF) is an important basis for the diagnosis of OAB. The emergence of home-uroflowmetry (HUF) has allowed the patients to record the VF while recording the uroflowmetry at home, and the voiding at home can show the real voiding situation. However, the use of HUF to assess OAB in children and its clinical significance has not been reported in the literature. Thus, this study investigate the value of HUF in evaluation of voiding function in children with OAB and survey the VF of healthy children in Mainland China. MATERIALS AND METHODS: From May 2021 to July 2023, 52 children with OAB aged 7-10 years, 48 age-matched volunteers (control group) accepted HUF. Daytime VF and nighttime VF, voided volume (VV) per time, 24-h voided volume (24h-VV), maximum flow rate (Qmax), voiding time (VT), and uroflow pattern were recorded and compute corrected maximum urine flow rate (cQmax). VF in 600 health pupils (7-10 years) from five primary schools in Henan Province China were selected for questionnaire survey by cross-sectional survey and multi-stage sampling methods. RESULTS: 52 children with OAB and 48 healthy children completed the available 48-h HUF recordings. 24-hour, daytime, and nighttime VF, and cQmax were higher in the OAB group than in the control group (P < 0.05). However, average VV, Qmax, and VT were lower in the OAB group than in the control group (P < 0.05). There was no significant difference in 24h-VV between two groups (P > 0.05). A total of 502 questionnaires qualified for statistical analysis, and the 24h-VF was 6.3 ± 0.95 times, daytime VF was 5.6 ± 0.89 times, and nighttime VF was 0.7 ± 0.59 times. There was no significant difference in the comparison of 24-h, daytime, and nighttime VF between boys and girls and in the comparison of VF by age (P > 0.05). Compared with the results of the questionnaire, the difference of VF in HUF control group was not statistically significant (P > 0.05). CONCLUSIONS: The VF in children is similar to that of adults and the HUF is a useful tool with the ability to more realistically record changes in voiding function in children with OAB.

6.
Age Ageing ; 53(8)2024 Aug 06.
Article de Anglais | MEDLINE | ID: mdl-39148435

RÉSUMÉ

BACKGROUND: Pain is a dynamic experience that varies over time, but it remains unknown whether trajectories of pain are associated with subsequent cognitive decline. The purpose of this study was to identify distinct trajectories of pain presence and activity-limiting pain and investigate their longitudinal associations with the rate of subsequent cognitive decline in older adults. METHODS: A total of 5685 participants from the English Longitudinal Study of Ageing (ELSA) and 7619 participants from the Health and Retirement Study (HRS) were included. Pain presence trajectories were identified over eight years in the ELSA and 10 years in the HRS, while trajectories of activity-limiting pain were identified over 10 years in the HRS. We utilised linear mixed-effects models to investigate the long-term relationship between pain trajectories and the rate of cognitive decline across various domains, including memory, orientation, executive function and global cognition. RESULTS: Three pain presence trajectories were identified. Moderate-increasing and high-stable groups exhibited steeper declines in global cognition than the low-stable group. Furthermore, individuals in the moderate-increasing group experienced a more rapid decline in executive function, while the high-stable group showed a faster decline in orientation function. Two trajectories of activity-limiting pain were identified, with the moderate-increasing group experiencing a faster decline in orientation function and global cognition. CONCLUSIONS: The trajectories of both pain presence and activity-limiting pain are linked to the rate of subsequent cognitive decline among older people. Interventions for specific pain trajectories might help to delay the decline rate of cognition in specific domains.


Sujet(s)
Dysfonctionnement cognitif , Douleur , Humains , Sujet âgé , Mâle , Femelle , Études longitudinales , Dysfonctionnement cognitif/épidémiologie , Dysfonctionnement cognitif/psychologie , Dysfonctionnement cognitif/diagnostic , Douleur/psychologie , Douleur/diagnostic , Douleur/épidémiologie , Cognition , Sujet âgé de 80 ans ou plus , Adulte d'âge moyen , Facteurs temps , Vieillissement/psychologie , Fonction exécutive , Facteurs de risque , Angleterre/épidémiologie , Facteurs âges
8.
Org Biomol Chem ; 22(27): 5618-5628, 2024 Jul 10.
Article de Anglais | MEDLINE | ID: mdl-38910460

RÉSUMÉ

An efficient and metal-free method for the synthesis of 3-aryl pyrido[1,2-a]indoles from aryne intermediates and 2-pyridinyl-substituted p-QMs was successfully developed under ambient conditions. The reaction offered a novel and practical protocol to access some diverse functional molecules in good to excellent yields. The proposed mechanism indicated that the reaction proceeded via a formal [3 + 2] cycloaddition step.

10.
J Environ Manage ; 365: 121513, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-38909574

RÉSUMÉ

Situated in the north of the Qinghai-Tibet Plateau, the Qaidam Basin experiences limited precipitation and significant evaporation. Despite these conditions, it stands out as one of the most densely distributed lakes in China. The formation of these lakes is controversial: whether the lake water primarily originates from local precipitation or external water sources. To address this issue, this paper explores the recharge sources of lakes in the Qaidam Basin and the circulation patterns of groundwater from a remote sensing perspective. Based on deep learning networks, we optimized the soft object regions of the Object-Contextual Representations Network (OCRNet) and proposed the Remote·Sensing Adaptive-Improved OCRNet (RSA-IOCRNet). Compared with seven other networks, RSA-IOCRNet obtained better experimental results and was used to construct an area sequence of 16 major lakes in the Qaidam Basin. Combined with multi-source data, the comprehensive analysis indicates no significant correlation between climatic factors and lake changes, while an obvious correlation between lakes and groundwater changes in the eastern Qaidam, consisting with the results of the field survey. Deep-circulating groundwater recharges numerous Qaidam lakes through upwelling from fault zones, such as Gasikule Lake and Xiaochaidan Lake. Groundwater in the Qaidam Basin is more depleted in hydrogen-oxygen isotope characteristics than surface water in the basin, but similar to some river water in the endorheic Tibetan Plateau. This indicates that Tibetan seepage water, estimated at approximately 540 billion m3/a, is transported through the Qaidam Basin via deep circulation. Moreover, it rises to recharge the groundwater and lakes within this basin through fracture zones, extending to various arid and semi-arid regions such as Taitema Lake. This work provides a new perspective on the impact of deep groundwater on lakes and water circulation in these areas.


Sujet(s)
Surveillance de l'environnement , Nappe phréatique , Lacs , Technologie de télédétection , Nappe phréatique/analyse , Nappe phréatique/composition chimique , Surveillance de l'environnement/méthodes , Chine , Tibet
11.
BMC Pediatr ; 24(1): 333, 2024 May 14.
Article de Anglais | MEDLINE | ID: mdl-38745164

RÉSUMÉ

BACKGROUND: The risk factors for hemorrhagic cystitis (HC) in children undergoing hematopoietic stem cell transplantation (HSCT) are unclear. Therefore, we conducted this systematic review and meta-analysis to investigate the risk factors for HC in children undergoing HSCT. METHODS: We performed this meta-analysis by retrieving studies from PubMed, EMBASE, and the Cochrane Library up to October 10, 2023, and analyzing those that met the inclusion criteria. I2 statistics were used to evaluate heterogeneity. RESULTS: Twelve studies, including 2,764 patients, were analyzed. Male sex (odds ratio [OR] = 1.52; 95% confidence interval [CI], 1.16-2.00; p = 0.003, I2 = 0%), allogeneic donor (OR = 5.28; 95% CI, 2.60-10.74; p < 0.00001, I2 = 0%), human leukocyte antigen (HLA) mismatched donor (OR = 1.86; 95% CI, 1.00-3.44; p = 0.05, I2 = 31%), unrelated donor (OR = 1.58; 95% CI, 1.10-2.28; p = 0.01, I2 = 1%), myeloablative conditioning (MAC) (OR = 3.17; 95% CI, 1.26-7.97; p = 0.01, I2 = 0%), busulfan (OR = 2.18; 95% CI, 1.33-3.58; p = 0.002, I2 = 0%) or anti-thymoglobulin (OR = 1.65; 95% CI, 1.07-2.54; p = 0.02, I2 = 16%) use, and cytomegalovirus (CMV) reactivation (OR = 2.64; 95% CI, 1.44-4.82; p = 0.002, I2 = 0%) were risk factors for HC in children undergoing HSCT. CONCLUSIONS: Male sex, allogeneic donor, HLA-mismatched, unrelated donor, MAC, use of busulfan or anti-thymoglobulin, and CMV reactivation are risk factors for HC in children undergoing HSCT.


Sujet(s)
, Transplantation de cellules souches hématopoïétiques , Hémorragie , Enfant , Femelle , Humains , Mâle , /étiologie , Transplantation de cellules souches hématopoïétiques/effets indésirables , Hémorragie/étiologie , Facteurs de risque , Facteurs sexuels , Conditionnement pour greffe/effets indésirables
12.
Ann Hematol ; 103(9): 3795-3800, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-38802593

RÉSUMÉ

Acute myeloid leukemia (AML) with t(8;21) (q22;q22), which forms RUNX1::RUNX1T1 fusion gene, is classified as a favorable-risk group. However, the presence of mutations in KIT exon 17 results in an adverse prognosis in this group. Avapritinib, a novel tyrosine kinase inhibitor, was designed to target KIT mutation. We report a retrospective study of four pediatric patients with AML with t(8:21) and KIT exon 17 mutation who were treated with avapritinib, three of them failed to demethylate drugs and donor lymphocyte infusion targeting RUNX1::RUNX1T1-positivity after allogeneic hematopoietic stem cell transplantation (allo-HSCT). So far, all patients with RUNX1::RUNX1T1 positivity had turned negative after 1, 9, 7, 2 months of avapritinib treatment. The common adverse effect of avapritinib is neutropenia, which is well-tolerated. This case series indicates that avapritinib may be effective and safe for preemptive treatment of children with AML with t(8;21) and KIT mutation after allo-HSCT, providing a treatment option for preventing relapse after allo-HSCT.


Sujet(s)
Chromosomes humains de la paire 21 , Chromosomes humains de la paire 8 , Transplantation de cellules souches hématopoïétiques , Leucémie aigüe myéloïde , Mutation , Protéines proto-oncogènes c-kit , Translocation génétique , Humains , Leucémie aigüe myéloïde/génétique , Leucémie aigüe myéloïde/thérapie , Leucémie aigüe myéloïde/traitement médicamenteux , Mâle , Protéines proto-oncogènes c-kit/génétique , Femelle , Enfant , Chromosomes humains de la paire 21/génétique , Chromosomes humains de la paire 8/génétique , Enfant d'âge préscolaire , Pyrazines/usage thérapeutique , Pyrazines/effets indésirables , Adolescent , Pyrazoles/usage thérapeutique , Pyrazoles/effets indésirables , Protéines de fusion oncogènes/génétique , Études rétrospectives , Pyrroles/usage thérapeutique , Pyrroles/effets indésirables , Sous-unité alpha 2 du facteur CBF/génétique , Triazines
13.
Materials (Basel) ; 17(9)2024 Apr 26.
Article de Anglais | MEDLINE | ID: mdl-38730852

RÉSUMÉ

Lunar mare basalt is recognized as an important in situ resource on the lunar surface. However, the significant compositional variability of lunar mare basalts introduces uncertainties concerning the potential for their use in fabricating fibers and composite materials. This study investigates the impact of different components on the fiber-forming capabilities of mare basalts by simulating the compositions of basalts collected from several well-known lunar missions and then preparing simulated lunar mare basalt fibers. Raman spectroscopy is primarily employed for analysis and characterization, using "peak area normalization" to explore the impact of compositional fluctuations in the simulated lunar mare basalts on the glass network structure. The findings indicate that an increase in the Fe content raises the likelihood of basalt fibers crystallizing. Additionally, Fe3+ is shown to substitute for Si and Al in constructing bridging oxygen bonds in the network structure, albeit reducing the overall polymerization of the network. Meanwhile, Fe2+ acts as a network modifier to enhance the mechanical properties of the fibers.

15.
Glob Chang Biol ; 30(4): e17279, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38619007

RÉSUMÉ

There are close links between solar UV radiation, climate change, and plastic pollution. UV-driven weathering is a key process leading to the degradation of plastics in the environment but also the formation of potentially harmful plastic fragments such as micro- and nanoplastic particles. Estimates of the environmental persistence of plastic pollution, and the formation of fragments, will need to take in account plastic dispersal around the globe, as well as projected UV radiation levels and climate change factors.


Sujet(s)
Énergie solaire , Rayons ultraviolets , Rayons ultraviolets/effets indésirables , Changement climatique , Pollution de l'environnement , Temps (météorologie)
16.
Ying Yong Sheng Tai Xue Bao ; 35(2): 424-430, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-38523100

RÉSUMÉ

Canopy spectral composition significantly affects growth and functional traits of understory plants. In this study, we explored the optimal light condition suitable for enhancing Scutellaria baicalensis's yield and quality, aiming to provide scientific reference for the exploitation and utilization of medicinal plant resources in the understory of forests. We measured the responses of growth, morphology, biomass allocation, physiological traits, and secon-dary metabolites of S. baicalensis to different light qualities. S. baicalensis was cultured under five LED-light treatments including full spectrum light (control), ultraviolet-A (UV-A) radiation, blue, green, and red light. Results showed that UV-A significantly reduced plant height, base diameter, leaf thickness, leaf area ratio, and biomass of each organ. Red light significantly reduced base diameter, biomass, effective quantum yield of photosystem Ⅱ (ФPSⅡ), and total flavonoid concentration. Under blue light, root length and total biomass of S. baicalensis significantly increased by 48.0% and 10.8%, respectively, while leaf number and chlorophyll content significantly decreased by 20.0% and 31.6%, respectively. The other physiological and biochemical traits were consistent with their responses in control. Our results suggested that blue light promoted photosynthesis, biomass accumulation, and secondary metabolite synthesis of S. baicalensis, while red light and UV-A radiation negatively affected physiological and biochemical metabolic processes. Therefore, the ratio of blue light could be appropriately increased to improve the yield and quality of S. baicalensis.


Sujet(s)
Plantes médicinales , Scutellaria baicalensis , Scutellaria baicalensis/composition chimique , Scutellaria baicalensis/métabolisme , Photosynthèse , Flavonoïdes , Chlorophylle/métabolisme
17.
Photochem Photobiol Sci ; 23(4): 629-650, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38512633

RÉSUMÉ

This Assessment Update by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) considers the interactive effects of solar UV radiation, global warming, and other weathering factors on plastics. The Assessment illustrates the significance of solar UV radiation in decreasing the durability of plastic materials, degradation of plastic debris, formation of micro- and nanoplastic particles and accompanying leaching of potential toxic compounds. Micro- and nanoplastics have been found in all ecosystems, the atmosphere, and in humans. While the potential biological risks are not yet well-established, the widespread and increasing occurrence of plastic pollution is reason for continuing research and monitoring. Plastic debris persists after its intended life in soils, water bodies and the atmosphere as well as in living organisms. To counteract accumulation of plastics in the environment, the lifetime of novel plastics or plastic alternatives should better match the functional life of products, with eventual breakdown releasing harmless substances to the environment.


Sujet(s)
Matières plastiques , Polluants chimiques de l'eau , Humains , Matières plastiques/toxicité , Écosystème , Rayons ultraviolets , Changement climatique , Polluants chimiques de l'eau/analyse
18.
Water Res ; 252: 121191, 2024 Mar 15.
Article de Anglais | MEDLINE | ID: mdl-38309065

RÉSUMÉ

The solid-liquid separation is an indispensable and primary link in the process of sludge treatment and disposal. The past research was focused primarily on the technique explorations of sludge dewatering and always disregarded the internal pore structure and water migration behavior in sludge. In this work, the real three-dimensional pore structure of sludge was obtained by Nano-CT. Based on this, a pore-scale heterogeneous sludge micromodel was firstly presented, and the water flooding experiment was carried out to visualize the water migration behavior. The results showed that the sludge structure transformed from sheet-like floc to microsphere particles, and then agglomerated into large globular granules during anaerobic ammonia oxidation. And the equivalent pore size increases from 342 µm to 617 µm, improving the sludge dewaterability characterized by capillary suction time (CST). The most significant implication of this work was revealing the critical role of invalid connected pore in sludge dewatering. Such pore was not contributed to fluid flow but the circulating vortex in it even induced energy dissipation, thus deteriorated the sludge dewaterability. This work may be helpful to understand the critical role of pore characteristic in water migration and shed light on the new dewatering techniques from the perspective of regulating sludge structure.


Sujet(s)
Eaux d'égout , Élimination des déchets liquides , Eaux d'égout/composition chimique , Élimination des déchets liquides/méthodes , Eau/composition chimique
19.
Polymers (Basel) ; 16(4)2024 Feb 07.
Article de Anglais | MEDLINE | ID: mdl-38399840

RÉSUMÉ

Water-based chloroprene latex is a solvent-free, environmentally friendly adhesive. Currently, its market demand is growing rapidly. However, there are problems such as a lack of heat resistance and poor mechanical properties, which limit its application. The introduction of vinyl-POSS (OVS) into the resin structure can effectively improve the thermal stability of chloroprene adhesives. In this paper, modified waterborne chloroprene latex was prepared by copolymerization of methyl methacrylate and OVS with chloroprene latex. The results showed that vinyl-POSS was successfully grafted onto the main chain of the waterborne chloroprene latex, and the modified waterborne chloroprene latex had good storage stability. With the increase in vinyl-POSS, the tensile strength of the chloroprene latex firstly increased and then decreased, the tensile property (peel strength of 20.2 kgf) was maintained well at a high temperature (100 °C), and the thermal stability of the chloroprene latex was improved. When the addition amount was 4%, the comprehensive mechanical properties were their best. This study provides a new idea for the construction of a new and efficient waterborne chloroprene latex system and provides more fields for the practical application of waterborne chloroprene latex. This newly developed vinyl-POSS modified chloroprene latex has great application potential for use in home furniture, bags, and seat cushions.

20.
Nanoscale ; 16(11): 5674-5684, 2024 Mar 14.
Article de Anglais | MEDLINE | ID: mdl-38391256

RÉSUMÉ

Passive cooling materials, as a promising choice for mitigating the global energy crisis, have limited use as their cooling effects are usually weakened or lost by dust contamination. In this study, a passive cooling polyethylene (PE) film with self-cleaning properties is prepared by picosecond laser ablation. Numerous root-like hierarchical porous micro/nano-structures were obtained on the double side of the PE film. The outside (toward air) shows excellent self-cleaning, corrosion resistance, and anti-friction properties. The inside (towards crops) further reduced the transmittance and water vapor evaporation (keeping the soil moist). Compared with the pristine PE film, the transmittance of the as-prepared double-sided micro/nano-structured PE film decreased by about 40%. In addition, during the crop cultivation experiment, the temperature of the crop leaves was reduced by 2.7-7 °C and showed a higher plant height and greater leaf width under the cover of the laser-treated film. This demonstrates that the passive cooling PE film has an excellent temperature regulation ability and good practical application effects. This study proposes a simple strategy based on a picosecond laser for the preparation of passive cooling materials, which are beneficial for alleviating energy crises and promoting sustainable development.

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