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Sulfide-containing wastewater, characterized by its foul odor, corrosiveness, and toxicity, can endanger human health. Fluidized-bed homogeneous crystallization (FBHC) avoids the excessive sludge production commonly associated with conventional chemical precipitation methods. In this study, FBHC is used to treat sulfur-containing synthetic wastewater. Furthermore, nickel-containing wastewater was utilized as a precipitant in the system, hence the advantage of simultaneous sulfur and nickel removal from the wastewater. The operating parameters, including pH, a precipitant dosage of [Ni2+]0/[S2-]0, and cross-sectional surface loading (LS, kg/m2h) are optimized. The optimum operating conditions of pH 9.8 ± 0.3, [Ni2+]0/[S2-]0 = 0.8, and LS = 1.5 kg/m2h results in total sulfur removal (TR) of 95.7% and crystallization ratio (CR) of 94.8%. The effect of organic compounds (acetic acid, oxalic acid, EDTA, and citric acid) and inorganic ions (NO3-, CO32-, PO43-, F-, and Cl-) on the nickel sulfide granulation process was discussed.
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PURPOSE: To explore the spiritual needs of community-dwelling older people living with early-stage dementia. DESIGN: A descriptive qualitative research design with purposive sampling was used. METHODS: Ten older people who were receiving home care services from a mental hospital in central Taiwan were recruited. In-depth semistructured interviews were conducted and content analysis was performed. FINDINGS: Four themes emerged that described the spiritual wishes and needs of older people with early-stage dementia: the wish to turn back time, the need to instill meaning into past experiences, the need to rely on faith-based strength, and the wish to have one's remaining life under control. The spiritual needs centered on a strong yearning to engage in a tug-of-war with time to reverse the impaired memory and independence. CONCLUSIONS: This study provides insights into the spiritual needs of older people with early-stage dementia. They struggled to maintain a balance between independence and dependence, build a sense of self and value, seek guidance and support from religious faith, and retain control over their lives. CLINICAL RELEVANCE: The findings can be expected to help caregivers improve care of older people with dementia by empowering older people to hold onto control in their lives and providing opportunities for them to connect with others for fulfilling their spiritual needs.
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Demência/psicologia , Serviços de Assistência Domiciliar , Espiritualismo/psicologia , Idoso , Idoso de 80 Anos ou mais , Cuidadores , Demência/enfermagem , Feminino , Humanos , Vida Independente , Masculino , Pesquisa Qualitativa , TaiwanRESUMO
Due to heterogeneous morphological and immunophenotypic features, approximately 50% of peripheral T-cell lymphomas are unclassifiable and categorized as peripheral T-cell lymphomas, not otherwise specified. These conditions have an aggressive course and poor clinical outcome. Identification of actionable biomarkers is urgently needed to develop better therapeutic strategies. Epigenetic alterations play a crucial role in tumor progression. Histone modifications, particularly methylation and acetylation, are generally involved in chromatin state regulation. Here we screened the core set of genes related to histone methylation (KMT2D, SETD2, KMT2A, KDM6A) and acetylation (EP300, CREBBP) and identified 59 somatic mutations in 45 of 125 (36.0%) patients with peripheral T-cell lymphomas, not otherwise specified. Histone modifier gene mutations were associated with inferior progression-free survival time of the patients, irrespective of chemotherapy regimens, but an increased response to the histone deacetylase inhibitor chidamide. In vitro, chidamide significantly inhibited the growth of EP300-mutated T-lymphoma cells and KMT2D-mutated T-lymphoma cells when combined with the hypomethylating agent decitabine. Mechanistically, decitabine acted synergistically with chidamide to enhance the interaction of KMT2D with transcription factor PU.1, regulated H3K4me-associated signaling pathways, and sensitized T-lymphoma cells to chidamide. In a xenograft KMT2D-mutated T-lymphoma model, dual treatment with chidamide and decitabine significantly retarded tumor growth and induced cell apoptosis through modulation of the KMT2D/H3K4me axis. Our work thus contributes to the understanding of aberrant histone modification in peripheral T-cell lymphomas, not otherwise specified and the stratification of a biological subset that can benefit from epigenetic treatment.
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Proteínas de Ligação a DNA/metabolismo , Genes Modificadores/genética , Histonas/metabolismo , Linfoma de Células T Periférico/tratamento farmacológico , Linfoma de Células T Periférico/genética , Mutação , Proteínas de Neoplasias/metabolismo , Acetilação , Aminopiridinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Benzamidas/farmacologia , Linhagem Celular Tumoral , Análise Mutacional de DNA , Decitabina/farmacologia , Xenoenxertos , Histonas/genética , Humanos , Linfoma de Células T Periférico/mortalidade , Metilação , Camundongos , Prognóstico , Análise de Sobrevida , Células Tumorais CultivadasRESUMO
In this study, a fluidized bed reactor was used to compare heterogeneous and homogeneous crystallization for recovering magnesium ammonia phosphate (MAP) from the dewatering filtrate at a municipal water resource recovery facility. Investigating the factors affecting crystallization revealed that pH exerted a greater effect than the Mg/P molar ratio. The results of a heterogeneous crystallization experiment showed that removal efficiency of phosphate (RP%) and crystal efficiency of phosphate (CP%) were 68% and 66%, respectively, at a PO4-P concentration of 200 mg/L, pH of 8.0, and Mg/P molar ratio of 1.0 for 3 h. The reaction rate of heterogeneous crystallization was markedly higher than that of homogeneous crystallization. Those pellets produced through the heterogeneous crystallization exhibited a dense surface (particle size 0.5-1.0 mm; water content 8.7%). Through scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), and X-ray diffraction (XRD) examination, the crystallized patterns of the needle-shaped pellets were identified as MgNH4PO4·6H2O.
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Cristalização/métodos , Fosfatos/química , Reatores Biológicos , Magnésio/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodosRESUMO
BACKGROUND: The ideology of recovery addresses the autonomy of patients with mental illness and their ability to reconstruct a normal life. Empirical knowledge of this process of recovery and related factors remains unclear. PURPOSE: To assess the process of recovery and related factors in patients with mental illness. METHODS: This cross-sectional, correlational study was conducted on a convenience sample in a psychiatric hospital. Two-hundred and fifty patients with mental illness were recruited and were assessed using 3 instruments: Questionnaire about the Process of Recovery (QPR), Perceived Psychiatric Stigma Scale (PPSS), and Personal and Social Performance Scale (PSP). Data were analyzed using descriptive statistics, χ2, analysis of variance, and multiple linear regression analysis. RESULTS: Most of the participants were male, middle-aged, unmarried, educated to the senior high school level, employed, receiving home-care treatment, and diagnosed with schizophrenia. Those who were unemployed, living in a community rehabilitative house, and living in the community, respectively, earned relatively higher recovery scores (p < .05). The total scores of QPR and the 3 subscales were negatively correlated with PPSS (p < .01) and positively correlated with PSPS (p < .01; p < .05). Multiple regression analysis indicated that the factors of education, employment, having received community rehabilitative models, and stigma, respectively, significantly explained the recovery capacity of patients with mental illness. CONCLUSIONS: Community psychiatric nurses should provide care to help employed patients adapt to stresses in the workplace, strengthen their stigma-coping strategies, and promote public awareness of mental health issues by increasing public knowledge and acceptance of mental illness in order to minimize patient-perceived stigma and facilitate their recovery.
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Transtornos Mentais/psicologia , Adaptação Psicológica , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estigma SocialRESUMO
This paper reports on a novel technique for measuring wafer warpage, using the design concepts of moiré shift, digital moiré, autocollimator, and the scanning profiling method. The measurement system is divided into two parts: an optical moiré system and a phase analysis system. The optical arrangement can be adjusted to control the projection of a linear grating image onto the surface of a wafer to be reflected back into a CCD camera. The grating image acquired by the CCD camera is used for measurement whereas a reference grating image is obtained using the digital moiré method. By overlapping the two images of the measurement and the reference gratings, the corresponding moiré fringes are formed. The phase of the moiré fringes will change proportionally to the degree of warpage in the wafer, which can be measured by detecting variations in the phase shift of the moiré fringes in the scanning profile across the surface of the entire wafer. Measurement resolution can be controlled by adjusting the pitch size of the grating or the focal length of the focusing lens, or by adjusting the angle between the images of the measurement and reference gratings. Experiment results demonstrate that the proposed method is able to achieve an angular resolution of 0.2 µrad. As compared to the current warpage measurement techniques, the proposed method has the ability of high measurement resolution, high stability, and high flexibility.
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Silicon (Si) has been perceived as a promising anode material for lithium-ion batteries for decades due to its superior theoretical capacity, environmental benignity, and earth abundance. To accommodate the drastic volume expansion during lithiation, which is the primary drawback leading to poor cycling life, a novel structural design via fabricating the Marimo-like carbon nanotubes frameworks with silicon nanoparticle (SiNP) filling in internal space has been developed. This facile fabrication procedure involves an in-spaced polymerization process through ex situ polymerization, using pyrrole monomers with a soft organic template in which well-dispersed SiNPs are present. Carbonization post-treatment is then performed to construct rigid conductive networks. The thus-fabricated 3D Marimo-like hybrid structure exhibits a remarkably improved electrochemical performance compared with that of the simple ball-milling method, which mainly originates from their structural advantages, including the built-in buffer spaces and the robust line-to-line contact mode between the components. The state-of-the-art structure exhibits an optimal high-rate capability (422 mAh g(-1) at a current rate of 2 A g(-1)) and long cycling stability (916 mAh g(-1) for 200th cycles at a current rate of 0.2 A g(-1)) and achieves the requirements for industrial production with the facile and cost-effective synthetic approach.
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Magnetic CuO-Fe3O4 composite was fabricated by a simple hydrothermal method and characterized as a heterogeneous catalyst for phenol degradation. The effects of pH and bicarbonate ions on catalytic activity were extensively evaluated in view of the practical applications. The results indicated that an increase of solution pH and the presence of bicarbonate ions were beneficial for the removal of phenol in the CuO-Fe3O4 coupled with persulfate (PS) process. Almost 100% mineralization of 0.1 mM phenol can be achieved in 120 min by using 0.3 g/L CuO-Fe3O4 and 5.0 mM PS at pH 11.0 or in the presence of 3.0 mM bicarbonate. The positive effect of bicarbonate ion is probably due to the suppression of copper leaching as well as the formation of Cu(III). The reuse of catalyst at pH0 11.0 and 5.6 showed that the catalyst remains a high level of stability at alkaline condition (e.g., pH0 11.0). On the basis of the characterization of catalyst, the results of metal leaching and EPR studies, it is suggested that phenol is mainly destroyed by the surface-adsorbed radicals and Cu(III) resulting from the reaction between PS and Cu(II) on the catalyst. Taking into account the widespread presence of bicarbonate ions in waste streams, the CuO-Fe3O4/PS system may provide some new insights for contaminant removal from wastewater.
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Bicarbonatos/química , Cobre/química , Poluentes Ambientais/química , Compostos Férricos/química , Compostos Orgânicos/química , Sulfatos/química , Catálise , Concentração de Íons de Hidrogênio , Íons , Microscopia Eletrônica de Varredura , Oxirredução , Fenol/química , Espectroscopia Fotoeletrônica , Difração de Raios XRESUMO
Chemical oxo-precipitation (COP) is an enhanced precipitation method for boron removal with the conversion of boric acid to perborate anions. When using barium-based precipitant, the boron can be effectively precipitated as barium perborates (BaPBs). The phase transformation of BaPBs from amorphous (A-BaPB, Ba(B(OH)3OOH)2) to crystalline (C-BaPB, BaB2(OO)2(OH)4) form is crucial for effective boron removal. However, scaling up this phase transformation of BaPBs is hindered by poor diffusion. This study aims to promote the growth of C-BaPB through seed-induced crystal growth, eliminating the need for phase transformation. By examining the relationship between crystal growth rate and supersaturation, surface spiral growth was identified as the rate-limiting step of the growth of micron-sized seeds near pHpzc. To enable continuous crystal growth, granular seeds of C-BaPB were prepared and employed as the medium for fluidized-bed crystallization (FBC). The system reached steady state 3 hydraulic retention times, achieving 90% boron removal. The effect of surface loading, ionic strength, and dosages on steady-state crystal growth rate was studied, revealing a shift of the rate-limiting step in FBC to diffusion. Lastly, the system that constituted of two FBCs in-series for sequential crystallization of A-BaPB and C-BaPB was demonstrated. The integrated system provided 97.8% of boron removal from synthetic wastewater containing 500 mg-B/L, with 92.3% of boron crystallized on the granular seeds of BaPBs.
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Bário , Boro , Cristalização , Boro/química , Bário/química , Boratos/química , Precipitação Química , Poluentes Químicos da Água/químicaRESUMO
The mixture of copper and iron often results in materials with favorable properties. The material production processes involving these metals including electroplating produce hazardous wastewater. In this study, the Fluidized Bed Homogeneous Crystallization (FBHC) process was applied to treat iron and copper-containing wastewater. The initial iron copper particles were successfully recovered from synthetic wastewater with [Fe]0:[Cu]0 of 2:1, the total metal concentration of 3 mM, at effluent pH = 7.75 ± 0.75, with the upflow velocity (U) of 1.76 m/h. The agglomerates hardening process is a crucial step for initial particle synthesis. The SEM analysis reveals the spherical particle's densified crust and porous core. The particle formation mechanism which includes the formation of the nucleus, attachment of precipitate flakes, and densification of particles was proposed after microscopic observation. The initial particles synthesized were used to initiate the treatment of synthetic wastewater at the operating condition pH = 7.75 ± 0.5, [Fe]0:[Cu]0 of 2:1, the total metal concentration of 3 mM, [CO32-]0:[M]0 = 1.2:1, and U of 28.66 m/h which results in the total metal removal of 99% and crystallization ratio of 90% and 88% for iron and copper respectively. The conditions were then applied to treat electroplating wastewater and resulted in the total metal removal of 99% for both iron and copper and a crystallization ratio of 83% and 79% for iron and copper, respectively. The treatment provided advantages in terms of treating larger amounts of sludge while eliminating the need to provide seed thus yielding a higher purity of product.
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Cobre , Cristalização , Ferro , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água , Águas Residuárias/química , Cobre/química , Cobre/isolamento & purificação , Ferro/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Eliminação de Resíduos Líquidos/métodosRESUMO
Background: Peripheral T-cell lymphoma (PTCL) is a heterogeneous disease with dismal outcomes. We conducted an open-label, phase 2 nonrandomised, externally controlled study to evaluate the efficacy and safety of targeted agents plus CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone) (CHOPX) for PTCL in the front-line setting. Methods: Eligible patients were ≥18 years of age and newly diagnosed PTCL. Patients in the CHOPX group received standard CHOP at Cycle 1. Specific targeted agents were added from Cycle 2, decitabine if TP53 mut, azacytidine if TET2/KMT2D mut, tucidinostat if CREBBP/EP300 mut, and lenalidomide if without mutations above. Patients in the CHOP group received CHOP for 6 cycles. The primary endpoint was the complete response rate (CRR) at the end of treatment (EOT). Secondary endpoints included overall response rate (ORR), progression-free survival (PFS), overall survival (OS), and safety. The study was registered with ClinicalTrials.gov, NCT04480099. Findings: Between July 29, 2020, and Sep 22, 2022, 96 patients were enrolled and included for efficacy and safety analysis with 48 in each group. The study met its primary endpoint. CRR at EOT in the CHOPX group was superior to the CHOP group (64.6% vs. 33.3%, OR 0.27, 95%CI 0.12-0.64; p = 0.004). At a median follow-up of 24.3 months (IQR 12.0-26.7), improved median PFS was observed in the CHOPX group (25.5 vs. 9.0 months; HR 0.57, 95%CI 0.34-0.98; p = 0.041). The median OS was similar between two groups (not reached vs. 30.9 months; HR 0.55, 95%CI 0.28-1.10; p = 0.088). The most common grade 3-4 hematological and non-hematological adverse events in the CHOPX group were neutropenia (31, 65%) and infection (5, 10%). Interpretation: Targeted agents combined with CHOP demonstrated effective and safe as first-line treatment in PTCL. Biomarker-driven therapeutic strategy is feasible and may lead to promising efficacy specifically toward molecular features in PTCL. Funding: This study was supported by the National Key Research and Development Program (2022YFC2502600) and the General Program of the Shanghai Municipal Health Commission (202040400).
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Peripheral T cell lymphoma (PTCL) is a heterogeneous group of non-Hodgkin's lymphomas varying in clinical, phenotypic, and genetic features. The molecular pathogenesis and the role of the tumor microenvironment in PTCL are poorly understood, with limited biomarkers available for genetic subtyping and targeted therapies. Through an integrated genomic and transcriptomic study of 221 PTCL patients, we delineate the genetic landscape of PTCL, enabling molecular and microenvironment classification. According to the mutational status of RHOA, TET2, histone-modifying, and immune-related genes, PTCL is divided into 4 molecular subtypes with discrete patterns of gene expression, biological aberrations, and vulnerabilities to targeted agents. We also perform an unsupervised clustering on the microenvironment transcriptional signatures and categorize PTCL into 4 lymphoma microenvironment subtypes based on characteristic activation of oncogenic pathways and composition of immune communities. Our findings highlight the potential clinical rationale of future precision medicine strategies that target both molecular and microenvironment alterations in PTCL.
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Linfoma de Células T Periférico , Humanos , Linfoma de Células T Periférico/genética , Linfoma de Células T Periférico/metabolismo , Perfilação da Expressão Gênica , Genômica , Mutação , Microambiente Tumoral/genéticaRESUMO
Histone methyltransferase KMT2D is one of the most frequently mutated genes in diffuse large B-cell lymphoma (DLBCL) and has been identified as an important pathogenic factor and prognostic marker. However, the biological relevance of KMT2D mutations on tumor microenvironment remains to be determined. KMT2D mutations were assessed by whole-genome/exome sequencing (WGS/WES) in 334 patients and by targeted sequencing in 427 patients with newly diagnosed DLBCL. Among all 761 DLBCL patients, somatic mutations in KMT2D were observed in 143 (18.79%) patients and significantly associated with advanced Ann Arbor stage and MYC expression ≥ 40%, as well as inferior progression-free survival and overall survival. In B-lymphoma cells, the mutation or knockdown of KMT2D inhibited methylation of lysine 4 on histone H3 (H3K4), downregulated FBXW7 expression, activated NOTCH signaling pathway and downstream MYC/TGF-ß1, resulting in alterations of tumor-induced regulatory T cell trafficking. In B-lymphoma murine models established with subcutaneous injection of SU-DHL-4 cells, xenografted tumors bearing KMT2D mutation presented lower H3K4 methylation, higher regulatory T cell recruitment, thereby provoking rapid tumor growth compared with wild-type KMT2D via FBXW7-NOTCH-MYC/TGF-ß1 axis.
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Proteína 7 com Repetições F-Box-WD , Linfoma Difuso de Grandes Células B , Mutação , Proteínas Proto-Oncogênicas c-myc , Linfócitos T Reguladores , Humanos , Proteína 7 com Repetições F-Box-WD/metabolismo , Proteína 7 com Repetições F-Box-WD/genética , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Animais , Camundongos , Feminino , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Masculino , Linfócitos T Reguladores/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Receptores Notch/metabolismo , Pessoa de Meia-Idade , Linhagem Celular Tumoral , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/genética , Transdução de Sinais , Adulto , Progressão da Doença , IdosoRESUMO
The heterogeneous oxidation of azo dye Reactive Black B (RBB) by the photo-Fenton system catalyzed with an immobilized iron oxide, B1 (supported with SiO2 grain), was investigated. Reactive Black B oxidation was carried out in an expended-bed reactor in which the effect of B1 dosage on the decolorization and degradation of RBB was examined. Through pseudo-first-order kinetic studies, decolorization was found to be faster than degradation with a fixed rate constant ratio. By determining the iron dissolution from B1, RBB oxidation was supposed to mainly occur on the B1 surface, which catalyzed the generation of hydroxyl radicals in the photo-Fenton reaction. Accordingly, the efficiency of photo-Fenton could reach 100% and 91.2% of decolorization and degradation, respectively, in 300 minutes.
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Compostos Férricos/química , Naftalenossulfonatos/química , Catálise , Cinética , Oxirredução , Poluentes Químicos da Água/químicaRESUMO
This work demonstrates a novel chloride photo-electrochemical method for mineralizing citric acid. The electrolytic reactor with a length of 12 cm, a width of 12 cm and a height of 30 cm held 2.5 L of solution, which was involved in the batch reaction. Both anode and cathode were made of titanium coated with RuO2/IrO2. The results revealed that the solution pH dominated the production of hypochlorous acid (HOCl) oxidant in the presence of NaCl as direct current electricity was used. The chloride electrochemical process at pH 5.5 removed 59% of total organic carbon (TOC) in 4 h (NaCl = 200 mM, current = 5 A). UV irradiation (254 nm) in the reactor induced the photo-electrochemical reaction, increasing the TOC removal from 59% to 99.4%. Finally, the reaction pathway for citric acid mineralization was discussed with reference to the detection of intermediates using a liquid chromatography-mass spectrometry (LC-MS).
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Ácido Cítrico/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Cloro/química , Cromatografia Líquida , Técnicas Eletroquímicas , Concentração de Íons de Hidrogênio , Espectrometria de Massas , Oxirredução , Processos Fotoquímicos , Cloreto de Sódio/químicaRESUMO
Response surface methodology (RSM) is an effective tool for process optimization with multi-complex operational factors. The present work aims to model and optimize the photocatalytic oxidation (PCO) parameters of Reactive Red 195 (RR195) dye decoloration with the SiO2-supported Fe-Co catalyst (FCS) derived from a novel catalyst synthesis method, fluidized-bed crystallization (FBC) process, using Box-Behnken design (BBD) as the RSM statistical model. The Fe-Co@SiO2 catalyst was successfully fabricated using the FBC process, and it showed good catalytic activity and performance toward the degradation of RR195. The extent of the effects of pH, H2O2 dosage (HD), catalyst loading (CL), and operating time (t) on the decoloration of RR195 was studied. Hence, the order of variable significance follows the sequence: pH > t > CL > HD. pH has the most significant effect among the variables for RR195 decoloration. The decoloration efficiency predicted by the BBD model was 88.3% under the optimized operation conditions of initial pH of 3.15, 0.76 mM H2O2, 1.18 g L-1 FCS and 59.4 min of operating time. The actual decoloration efficiency was very close to the predicted value indicating that BBD can efficiently be utilized to optimize RR195 degradation with FCS under the PCO system.
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Compostos Azo , Peróxido de Hidrogênio/química , Modelos Estatísticos , Oxirredução , Dióxido de Silício , Processos Fotoquímicos , Compostos Azo/química , CatáliseRESUMO
This study aims to explore the reusability of wastewater treatment by-product for photo-Fenton process to treat an organic pollutant model. The optimal condition, reactive oxygen species (ROS), and kinetic approach in photo-Fenton process was discussed. The Metal oxide crystal pellets from are a by-product of the Fluidized-Bed Crystallization (FBC) process and can be used as a catalyst in the Photo-Fenton process. Electroplating wastewater containing iron and copper was treated via the FBC process using granulated Al(OH)3 as carrier seeds. The binary oxide of FeOOH and Cu2O on the Al(OH)3 surface (Fe0.66Cu0.33@Al(OH)3) was identified as the FBC by-product after characterization using FTIR and XPS analysis. In the photo-Fenton process, visible light from a fluorescence lamp with a wavelength of 400-610 nm was chosen as an irradiation source. Oxalic acid was added as chelating agent to form photosensitive iron oxalate species and hydrogen peroxide was applied as oxidant to generate active radical to decolorize and mineralize RB5 synthesized solution (100 mg/L). The operating conditions including the oxalic acid to pollutant ratio ([OA]0/[RB5]0) of 4.5-13.0, reaction pH (pHr) of 3-7 and initial to theoretical hydrogen peroxide molar ratio [H2O2]0/[ H2O2]theoretical of 35%-120% were optimized. Under the optimal conditions, pHr = 5.0; [H2O2]0/[RB5]0 at 75% stoichiometric and [OA]0/[RB5]0 = 9, the RB5 is almost completely decolorized after 210 min of operation and the mineralization efficiency is 58%. The contribution of â¢OH, O2â¢-, and O21 to the Photo-Fenton system was determined using ESR analysis with the addition of DMPO and TEMP as spin trap agents. The kinetic analysis reveals the observed rate constants kRB5, kOA and kR from fitting are 0.0120, 0.0054 and 0.0001 M-1s-1, respectively.
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Poluentes Ambientais , Peróxido de Hidrogênio , Peróxido de Hidrogênio/química , Cobre , Compostos Azo , Cinética , Luz , Óxidos/química , Ácido Oxálico , OxirreduçãoRESUMO
OBJECTIVES: This study investigated the association between the decline of the decayed, missing, and filled teeth (DMFT) index and several family-level and individual-level factors among 6- to 18-year-old Taiwanese children from 2012 to 2020. METHODS: This study used data from the 2012 and 2020 Taiwan National Oral Health Survey of Children and Adolescents. Both surveys used similar methods and were performed in the same study age group. A structured questionnaire was used to collect data on parents' sociodemographic background; the number of children in the family; oral health-related knowledge, attitudes, and behaviours; and children's dietary habits. Dental caries was recorded through standardized oral examinations. Multivariable multilevel zero-inflated negative binomial regression models were used to determine the association between family-level and individual-level factors and the DMFT index from 2012 to 2020. RESULTS: A total of 10 217 and 10 436 schoolchildren completed the oral examinations and questionnaires in the 2012 and 2020 surveys, respectively. The adjusted mean DMFT index of 12-year-old Taiwanese schoolchildren in 2020 was 2.01, denoting a significant decline from 2.50 in 2012 (adjusted mean ratio = 0.20, 95% confidence interval [CI] = 0.17, 0.23, p < .0001). Furthermore, children who often consumed sugar-rich drinks had a significantly higher risk (mean ratio = 1.05, 95% CI = 1.01, 1.10) of having DMFT than those who seldom consumed such drinks (p = .017). CONCLUSIONS: In the period of 2012-2020, the DMFT index among Taiwanese children significantly declined. Children who often consumed sugar-rich drinks had a higher DMFT index than those who seldom consumed such drinks. Our findings are valuable to paediatricians, dentists, nutritionists, and public health policymakers.
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Cárie Dentária , Criança , Adolescente , Humanos , Cárie Dentária/epidemiologia , Cárie Dentária/etiologia , Taiwan/epidemiologia , Estudos Transversais , Inquéritos de Saúde Bucal , Açúcares , Índice CPO , PrevalênciaRESUMO
This study investigated a heterogeneous photo-catalysis system by introducing a novel brick supported iron oxide (denoted as B1) for the heterogeneous photoassisted degradation of Reactive Black 5 (RB5) at pH value from 3 to 7 in a three-phase (gas-liquid-solid) fluidized bed reactor (3P-FBR). Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray powder diffraction (XRD) and N(2) adsorption/desorption were used to characterize the B1 catalyst. The in situ formation of hydrogen peroxide and the depletion of oxalic acid by photochemical cycle of Fe(III)-oxalate complex under UVA light (λ = 365 nm) were studied. The effects of the solution pH and the concentration of oxalic acid on the degradation of RB5 are elucidated. About 90% decolourization was measured and 80% of the total organic carbon (TOC) was eliminated at pH 5.0 after 120 min for 20 mg/L RB5 in presence of 10 g/L B1 catalyst, 30 mg/L oxalic acid under 15 W UVA light. A mechanism for the photocatalytic degradation of RB5 over B1 catalyst is proposed.
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Corantes/química , Compostos Férricos/química , Naftalenossulfonatos/química , Ácido Oxálico/química , Raios Ultravioleta , Poluentes Químicos da Água/química , Catálise , Corantes/efeitos da radiação , Naftalenossulfonatos/efeitos da radiação , Fotólise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/efeitos da radiação , Purificação da Água/métodosRESUMO
The strong oxidant, persulfate (PS, S2O82-), was applied to treat the synthetic wastewater of benzoic acid (BA) under UV irradiation. UVC light initiated a chain reaction that derived the sulfate radical (SO4â¢-) and hydroxyl radical (HOâ¢) from S2O82- ion. The experiment parameters, including light irradiation (UVA and UVC), pH, dose ratio ([PS]0/[BA]0), initial concentration ([BA]0, mg/L), was optimized based on degradation efficiency and total organic carbon (TOC) removal of BA, which reached up to 100% and 96%, respectively, under pH 3.0. The best dose ratio was close to equivalent stoichiometry (and [PS]0/[BA]0 = 15) for the treatment of 100 mg-BA/L, suggesting that UV/S2O82- was able to completely convert BA to carbon dioxide and water. The scavenging test showed that SO4â¢- contributed to about 60% of degradation rate, which the HO⢠predominated the mineralization rate, i.e., TOC removal. A consecutive kinetic model was proposed to clarify the reaction sequence and rate-determining factor of photo-persulfate oxidation for benzoic acid.