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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 319: 124538, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38833885

RESUMO

Growth period determination and color coordinates prediction are essential for comparing postharvest fruit quality. This paper proposes a tomato growth period judgment and color coordinates prediction model based on hyperspectral imaging technology. It utilizes the most effective color coordinates prediction model to obtain a color visual image. Firstly, hyperspectral images were taken of tomatoes at different growth periods (green-ripe, color-changing, half-ripe, and full-ripe), and color coordinates (L*, a*, b*, c, h) were obtained using a colorimeter. The sample set was divided by the sample set partitioning based on joint X-Y distances (SPXY). The support vector machine (SVM), K-nearest neighbors (KNN), and linear discriminant analysis (LDA) were used to discriminate growth period. Results show that the LDA model has the best prediction effect with a prediction set accuracy of 93.1%. In addition, effective wavelengths were selected using competitive adaptive reweighted sampling (CARS) and successive projections algorithm (SPA), and chromaticity prediction models were established using partial least squares regression (PLSR), multiple linear regression (MLR), principal component regression (PCR) and support vector machine regression (SVR) Finally, the color of each pixel of the tomato is calculated using the optimal model, generating a visual distribution image of the color coordinate. The results showed that hyperspectral imaging can non-destructively detect tomatoes' growth stage and color coordinates, providing great significance for designing a tomato quality grading system.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38607754

RESUMO

OBJECTIVE: To investigate predictors of anticoagulation efficacy in deep venous thrombosis (DVT) by ultrasound elastography (UE). METHODS: The basic clinical, laboratory and ultrasound treatment data of fifty-eight patients with DVT were collected and analyzed. Then the results of ultrasound after 3-month anticoagulation treatment were compared among different groups. Multiple logistic regression analysis was used to identify independent risk factors that affected anticoagulation efficacy. The predictive efficacy of each independent risk factor was accessed by drawing operating characteristic (ROC) curves. RESULTS: According to the regression analysis, the elastic modulus (OR = 0.631, P = 0.001) and strain rate ratio (OR = 0.332, P = 0.006) were identified as independent risk factors for the effectiveness of anticoagulation therapy in patients with DVT. According to the ROC curves, elastic modulus and strain rate ratio could predict effective anticoagulation therapy for DVT, and the optimal threshold values were 22.10 kPa and 1.80 respectively. The corresponding AUC values were 0.879 and 0.854, with a sensitivity of 71.4% and 59.5%, a specificity of 93.7%, and a Youden index of 65.1% and 62.7%, respectively. CONCLUSIONS: The elastic modulus (≤22.10 kPa) or strain rate ratio (≤1.80) of the thrombus were independent predictors for the effectiveness of anticoagulation therapy.

3.
Sensors (Basel) ; 24(4)2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38400403

RESUMO

To address the lightweight and real-time issues of coal sorting detection, an intelligent detection method for coal and gangue, Our-v8, was proposed based on improved YOLOv8. Images of coal and gangue with different densities under two diverse lighting environments were collected. Then the Laplacian image enhancement algorithm was proposed to improve the training data quality, sharpening contours and boosting feature extraction; the CBAM attention mechanism was introduced to prioritize crucial features, enhancing more accurate feature extraction ability; and the EIOU loss function was added to refine box regression, further improving detection accuracy. The experimental results showed that Our-v8 for detecting coal and gangue in a halogen lamp lighting environment achieved excellent performance with a mean average precision (mAP) of 99.5%, was lightweight with FLOPs of 29.7, Param of 12.8, and a size of only 22.1 MB. Additionally, Our-v8 can provide accurate location information for coal and gangue, making it ideal for real-time coal sorting applications.

4.
Mycobiology ; 52(1): 58-67, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38415174

RESUMO

The present study sought to propose Ganoderma guixiense sp. nov. as a new species based on phenotypic and genotypic evidence. Phylogenetic analyses were carried out based on the internal transcribed spacer (ITS), the large subunit of nuclear ribosomal RNA gene (nLSU), and the second subunit of RNA polymerase II (RPB2) sequence data. G. guixiense has been characterized by pileate basidiomata, long stipe, in addition to reddish-black zonate pileal surface. Basidiospores are broadly ellipsoid with one end tapering at maturity, and measuring 9-12.8 × 6.5-9.3 µm. Basidia are oval to subglobose. This study marks the first exploration of the biological characteristics of G. guixiense. The result indicated that the optimal medium of mycelial growth was observed on malt extract agar (MEA) and yeast extract peptone dextrose agar (YPD) while the optimal temperature was found to be 25-30 °C with pH range of 6-7.

5.
Environ Pollut ; 347: 123433, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38278405

RESUMO

The COVID-19 pandemic has resulted in a substantial surge in the usage of disposable plastic masks, generating a significant volume of waste and contributing to environmental pollution. Wetland ecosystems function as crucial repositories for terrestrial pollutants and are highly effective in retaining disposable masks composed mainly of PP material. These masks can endure extended periods in wetlands, experiencing natural degradation that may have potential implications on wetland ecosystems. Our findings demonstrate the natural aging process of disposable masks, resulting in the generation of microplastics (MPs) ranging in diameter from 10 to 30 µm over a 180-day timeframe. Examination of 16S rDNA data unveiled temporal fluctuations in microbial diversity in the wetland ecosystem. Initially, microbial diversity displayed a modest incline, which was succeeded by a subsequent decrease. With the progressive accumulation of plastic within the wetland, an ongoing decline in microbial diversity linked to nitrogen transformation was observed. This study provides valuable insights into the retention of disposable masks by wetlands amidst the COVID-19 pandemic, along with their consequential effects on wetland ecosystems, specifically pertaining to nitrogen cycling. It underscores the urgency of augmenting the safeguarding measures for wetland ecosystems.


Assuntos
COVID-19 , Microbiota , Humanos , Áreas Alagadas , Ecossistema , Polipropilenos , Pandemias , Plásticos , Envelhecimento , Nitrogênio
6.
Curr Res Transl Med ; 72(1): 103438, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38244303

RESUMO

Congenital sideroblastic anemia (CSA) is a group of disorders caused by different genetic mutations that result in low iron utilization and ineffective erythropoiesis. Current treatments are limited, and some patients do not respond to vitamin B6 therapy. Luspatercept is a novel erythropoietic maturation agent approved for adult ß-thalassemia and Myelodysplastic syndromes with ring sideroblasts (MDS-RS) associated with ineffective erythropoiesis. Here we report 2 patients with CSA due to mutations in ALAS2 and SLC25A38 genes who became unresponsive after a period of treatment with vitamin B6 and iron chelators but achieved transfusion independence and a markedly reduced spleen after combination with luspatercept.


Assuntos
Receptores de Activinas Tipo II , Anemia Sideroblástica , Doenças Genéticas Ligadas ao Cromossomo X , Proteínas Recombinantes de Fusão , Adulto , Humanos , 5-Aminolevulinato Sintetase , Receptores de Activinas Tipo II/efeitos adversos , Anemia Sideroblástica/tratamento farmacológico , Anemia Sideroblástica/genética , Anemia Sideroblástica/congênito , Fragmentos Fc das Imunoglobulinas/efeitos adversos , Proteínas Recombinantes de Fusão/efeitos adversos , Vitamina B 6
7.
Int J Mol Sci ; 24(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37834414

RESUMO

It is meaningful to understand the conversion pathways of nitrogen during the hydrothermal liquefaction process of microalgae to reveal the related reaction mechanisms and develop effective methods to prevent N from ending in biocrude, which eventually increases the quality of biocrude. Extending from our previous works that mainly focused on two high-protein (>50 wt%) microalgae (Chlorella sp. and Spirulina sp.), Nannochloropsis sp., which has a high lipid content (>70 wt%), was used as the feedstock for this project using the same methodology. The high lipid content in Na. induced less nitrogen during the oil phase and as a result, reduced the heteroatom content while also improving the quality of biocrude. It is worth noting that another investigation was conducted on the model compounds with different types of amino acids to specify the effects of the types of amino acids in the proteins in microalgae on the N pathway and their distribution in the products (aqueous phase, oil, solid, and gas). It was found that the basic amino acid in microalgae caused the formation of more N-heterocyclic compounds in the biocrude. The mass flow based on the mass balance was demonstrated to further refine the map showing the predicted reaction pathway of nitrogen from the previous version.


Assuntos
Chlorella , Microalgas , Temperatura , Aminoácidos , Microalgas/química , Nitrogênio , Água , Lipídeos , Biocombustíveis , Biomassa
8.
J Hazard Mater ; 452: 131336, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37027924

RESUMO

The marsh, a significant terrestrial ecosystem, has steadily developed the capacity to act as a microplastics collection place (MPs). Here, 180 days of exposure to three different polymer kinds of plastics: polyethylene (PE), polystyrene (PS), and polyvinyl chloride (PVC), were conducted in miniature wetlands (CWs). Water contact angle (WCA), scanning electron microscopy (SEM), Fourier transform infrared (FTIR), and High-throughput sequencing were used to study the succession of microbial community structure and function on MPs after 0, 90, and 180 days of exposure. The results showed that different polymers were degrading and aging differing degrees; PVC contained new functional groups with the symbols -CC-, -CO-, and -OH, while PE had the biggest range of contact angles (74.0-45.5°). Bacteria colonization was discovered on plastic surfaces, and as time went on, it became increasingly evident that the surfaces' composition had altered, and their hydrophobicity had diminished. The plastisphere's microbial community structure as well as water nitrification and denitrification were altered by MPs. In general, our study created a vertical flow-built wetland environment, monitored the impacts of plastic aging and breakdown products on nitrogen metabolizing microorganisms in wetland water, and offered a reliable site for the screening of plastic-degrading bacteria.


Assuntos
Microbiota , Plásticos , Áreas Alagadas , Nitrogênio , Polietileno , Água , Biofilmes
9.
Food Res Int ; 167: 112629, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37087205

RESUMO

The unique flavor and aroma characteristics of huajiao were not only influenced by cultivated varieties, maturity, but also geographic origin. This study compared the terpenoids of 48 species of huajiao using headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and electronic nose (E-nose). The E-nose results showed differences in huajiao from different origins and varieties, and from the PCA loading plots it was possible to conclude that some samples contained higher levels of hydrocarbons and alcohols, providing a preliminary discrimination between different species of huajiao. Further, GC-MS results showed that six key biomarkers could be used to distinguish red and green huajiao. Red huajiao in Central China contained more terpenoids than in other regions. Nine key biomarkers could be used to distinguish red huajiao from different regions. Oil huajiao exhibited a more distinct aroma in red huajiao. Green huajiao from Yunnan Province had more terpenoids than that from other provinces. The terpenoids content of Yunnan zhuyeqing was higher than other green huajiao. Heatmap analysis helped to find the most contributors of huajiao, which could be used as key terpenoids to differentiate huajiao of different regions or cultivars. Finally, through the correlation analysis of E-nose and GC-MS, it was found that the E-nose sensors could distinguish different huajiao by specific responses to some terpenoids in the samples.


Assuntos
Terpenos , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Terpenos/análise , Nariz Eletrônico , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/análise , China
10.
Clin Exp Med ; 23(2): 437-445, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35451668

RESUMO

To explore the clinicopathological characteristics, survival outcomes, and prognosis of very young gastric cancer (GC). From January 1, 2011 to January 1, 2021, GC patients under 30 years old treated in three tertiary hospitals were enrolled. Clinicopathological characteristics were summarized, prognostic factors and survival outcomes including overall survival (OS), disease-free survival (DFS), and progression-free survival (PFS) were retrospectively analyzed. One hundred patients were finally included, with a median age of 23 years.73 (73.0%) were female. Most patients had initial symptoms of abdominal pain (66.0%). The most common tumor locations were gastric antrum (38.0%) and gastric body (37.0%). The main histological types were diffuse (81.0%) and poorly differentiated (91.0%). Most patients presented with stage III-IV disease (82.0%) at diagnosis and the common sites of metastasis were ovary (39.5%) and peritoneum (27.6%). The mOS of the whole group was 23.3 months (95% CI 17.2-29.4). Moreover, the mOS of patients at stage I-II was not reached. The mOS of patients at stage III and stage IV was 40.6 months (95% CI 10.2-70.9) and 10.3 months (95% CI 8.9-11.6), respectively. The mDFS of stage I-III patients was 28.5 months (95% CI 14.7-42.3), and the mPFS of the metastatic patients was 4.5 months (95% CI 4.0-5.0). TNM stage (P = 0.005) and radical surgery (P = 0.001) were independent prognostic factors of overall survival. The very young GC were predominantly female, diffuse type, and advanced diagnosis. TNM stage and radical surgery were independent prognosis factors for overall survival.


Assuntos
Neoplasias Gástricas , Humanos , Feminino , Adulto Jovem , Adulto , Masculino , Prognóstico , Neoplasias Gástricas/patologia , Estadiamento de Neoplasias , Estudos Retrospectivos , Gastrectomia
11.
Sci Total Environ ; 854: 158675, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36089050

RESUMO

Activators affect the physical and chemical properties of carbon products. However, the effects of different activation mechanisms and pyrolysis conditions on the properties of carbon products still need to be explored. In this study, we obtained a new biochar by impregnation of reed powder with an alkali metal salt (CaCl2) under a specific pyrolysis procedure and pyrolysis conditions. Impregnation by CaCl2 can reduce the activation energy of the biomass while capturing and immobilizing oxygenated organic matter during pyrolysis. The new biochar has a high adsorption capacity of organic matters, for example Bisphenol A (BPA). The adsorption results showed that the modified biochar demonstrated a 364.5 % improvement in the adsorption capacity compared to the original biochar. The final performance enhancement was correlated with the confinement conditions of the environment and the procedure of pyrolysis. These procedures ultimately changed the pore distribution, functional group type, aromaticity, and degree of defects of the modified biochar. This study is important to screen synthetic pathways for identifying compounds with excellent adsorption effects.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Cloreto de Cálcio , Adsorção , Carvão Vegetal/química , Carbono , Poluentes Químicos da Água/análise
12.
Blood Cells Mol Dis ; 98: 102708, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36334505

RESUMO

Severe aplastic anemia (SAA) is a bone marrow failure disorder caused by autoimmune dysfunction. The presentation by dendritic cells (DCs) is the key step in initiating the immune response against unknown antigens in SAA patients. In the previous phase, we found that compared to healthy controls, patients with SAA had an increased proportion of circulating myeloid/conventional dendritic cells (mDCs/cDCs) with enhanced phagocytosis, more secretion of Th1-type cytokines (IL-2, TNF-α, IFN-γ) in the bone marrow, and a reduced proportion of Treg cells. In this study, we found that cDCs sorted from SAA patients had higher expression level of HLA-DQ, co-stimulatory molecules CD86, PTK and ERK1/2 than the remission SAA patients and healthy controls. Moreover, downregulation of HLA-DQ protein levels on cDCs derived from SAA patients resulted in reduced phagocytosis rate and CD86 expression of cDCs. When the cDCs above were co-cultured with CD4+ cells from the same patients, reduced secretion of Th1 type of lymphocyte cytokines was observed. Analysis of clinically relevant data suggests that HLA-DQ expression levels were closely related to disease severity and immune status of patients. These findings show that the role of HLA-DQ in the immunopathogenesis of SAA is potentially important and worth further study.


Assuntos
Anemia Aplástica , Humanos , Medula Óssea/patologia , Fator de Necrose Tumoral alfa , Antígenos HLA-DQ/metabolismo
13.
J Fungi (Basel) ; 8(11)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36422009

RESUMO

This study reports four new species and three new record species of Orbiliaceous fungi from China. Orbilia baisensis, O. hanzhongensis, O. nanningensis and O. pinea are described as new species and O. crenatomarginata, O. vinosa and O. vitalbae are described as new record species. All the studied species were identified by morphological characteristics and phylogenetic analysis of internal transcribed spacer (ITS) and large subunit (LSU) sequences. Four new species are described based on their sexual and asexual states, and their differences with the close relatives were compared and discussed.

14.
Sci Total Environ ; 844: 157164, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-35798106

RESUMO

Variations in the chemical composition of geofluids and of gas fluxes are significant parameters for understanding mud volcanism and correctly estimate their emissions in carbon species, particularly greenhouse gas, methane. In this study, muddy water and gas samples were collected from the Anjihai, Dushanzi, Aiqigou, and Baiyanggou mud volcanoes in the southern Junggar Basin during the four seasons, around a year. This region hosts the most active mud volcanism throughout China. Gas and water were analyzed for major molecular compositions, carbon and hydrogen isotopes of the gas phase, as well as cations and anions, hydrogen and oxygen isotopes of water. The emitted gases are dominated by CH4 with some C2H6, CO2, and N2. The seasonal changes in the chemical composition and carbon isotopes of emitted gases are not significant, whereas clear variations in the amounts of cations and anions dissolved in the water are reported. These are higher in spring and summer than autumn and winter. The CH4, CO2, and C2H6 fluxes are 157.3-1108 kg/a, 1.8-390.1 kg/a, and 10.2-118.7 kg/a, respectively, and a clear seasonal trend of the gas seepage flux has been observed. In January, the macro-seepage flux of open vents is ≥65 % higher than in April, whereas the micro-seepage flux significantly decreased, probably due to the frozen shallow ground and blockage of soil fractures around the vents by heavy snow and ice during January. This probably causes an extra gas pressure transferred to the major vents, resulting in higher flux of the macro-seepage in the cold season. However, the total flux of the whole mud volcano system is generally consistent around a year.


Assuntos
Dióxido de Carbono , Óxido Nitroso , Carbono , Dióxido de Carbono/análise , China , Monitoramento Ambiental , Gases , Hidrogênio , Metano/análise , Óxido Nitroso/análise , Estações do Ano , Água
15.
Artigo em Inglês | MEDLINE | ID: mdl-35742453

RESUMO

The precipitation of struvite (MgNH4PO4·6H2O) is considered to be a promising method for the recovery of phosphate from wastewater. In this review, the kinetic models, which are commonly used to explain the process of struvite crystallization, are described. The mixed-suspension mixed-product removal (MSMPR) model is based on the population balance equation (the size-dependent growth model and the size-independent growth model). Thereafter, the first-order kinetic fitting model that aligned with concentration changes in the substrate is summarized. Finally, the several physical and chemical factors that affected the efficiency of struvite crystallization are determined. The supersaturation ratio, which is seen as the driving force of struvite crystallization, is the main factor that influences crystallization; however, it cannot be used in practical applications of engineering because it is indirectly associated with the following factors: pH, the molar ratio of Mg:N:P, and the interference of foreign impurities. In this study, we present conclusions that should be used to guide further research studies, and encourage the engineering practice of wastewater treatment with struvite precipitation.


Assuntos
Fosfatos , Águas Residuárias , Precipitação Química , Cristalização , Cinética , Fosfatos/química , Fósforo/química , Estruvita/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química
16.
Food Chem ; 386: 132864, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35509167

RESUMO

The quality of tomatoes is usually predicted by measuring a single index, rather than a comprehensive index. To find a comprehensive index, visible and near infrared (Vis-NIR) hyperspectral imaging was used for capturing the images of three varieties of tomatoes, and twelve quality indexes were measured as the reference standards. The changing trends and correlations of different indexes were analyzed, and comprehensive quality index (CQI) was proposed through factor analysis. The characteristic wavelengths were selected by successive projection algorithm (SPA) based on the hyperspectral data, which was used to establish three regression models for CQI prediction. The result indicated that MLR achieved good performance withRV2 = 0.87, RMSEV = 1.33 and RPD = 2.58. After that, spatial distribution map was generated to visualize the CQI in tomato fruit. This study indicated that the comprehensive quality of tomatoes can be predicted non-destructively based on hyperspectral imaging and chemometrics, determining the optimal harvesting period.


Assuntos
Imageamento Hiperespectral , Solanum lycopersicum , Algoritmos , Frutas , Análise dos Mínimos Quadrados
17.
Iran J Public Health ; 51(1): 96-104, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35223630

RESUMO

BACKGROUND: U To analyze the effect of metformin hydrochloride combined with insulin pump for gestational diabetes mellitus (GDM). METHODS: Overall, 216 patients with GDM in Zhangqiu Maternity and Child Care Hospital, Jinan, China from Aug 2018 to Dec 2020 were enrolled and randomized into research and control groups. Patients in the control group were treated with insulin pump, while those in the research group were treated with metformin hydrochloride combined with insulin pump. The clinical efficacy, blood glucose levels, serum Betatrophin, C reactive protein (CRP), Cystatin C (Cys-C), homocysteine (Hcy), adiponectin, tumor necrosis factor (TNF-α), interleukin-6 (IL-6) content, incidence of adverse pregnancy outcomes and incidence of adverse newborns of patients in the two groups were compared. RESULTS: After treatment, the total clinical efficiency of the research group was 84.26%, significantly higher than that of the control group (68.52%). The levels of FPG, 2hPG, HbAlc, serum Betatrophin, CRP, CysC, Hcy, adiponectin factors, TNF-α, and IL-6 in the research group were lower than those in the control group, with statistically significant differences (P<0.05). The overall incidence of adverse pregnancy outcomes was 10.19% in the research group, and 25.93% in the control group. The comparative differences between the two groups were statistically significant (P<0.05). The overall incidence of adverse newborns was 9.26% in the research group, and 21.30% in the control group. The comparative differences between the two groups were statistically significant as well (P<0.05). CONCLUSION: Metformin hydrochloride combined with insulin pump for GDM can significantly reduce blood glucose level, regulate serum protein factor levels, and improve adverse outcomes for mother and child, which deserves clinical promotion.

18.
Spectrochim Acta A Mol Biomol Spectrosc ; 272: 121016, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35158140

RESUMO

Hyperspectral imaging was attempted to evaluate the internal and external quality of 'Feicheng' peach by providing the spectral and spatial data simultaneously. Mask-image was created from hyperspectral image at 810 nm and used to segment the fruit region where the average spectrum, after area normalization, was obtained for soluble solids content (SSC) and firmness evaluation. Pixel size and area were used for diameter and weight estimation. Then effective wavelengths were selected by competitive adaptive reweighted sampling (CARS) and random frog (RF), and employed to develop multiple linear regression (MLR) models. The more effective prediction performances emerged from CARS-MLR model withRV2 = 0.841, RMSEV = 0.546, RPD = 2.51 for SSC andRV2 = 0.826, RMSEV = 1.008, RPD = 2.401 for firmness, followed by creating pixel-wise and object-wise visualization maps for quantifying SSC and firmness. Furthermore, peach diameter was estimated by calculating the minimum bounding rectangle with an average percentage error of 1.01 %, and the MLR model forweightpredictionachieveda good performance ofRV2 = 0.957, RMSEV = 9.203, and RPD = 4.819. The overall results showed that hyperspectral imaging could be used as an effective and non-destructive tool for evaluating the internal and external quality attributes of 'Feicheng' peach, and provided a holistic approach to develop online grading systems for quality tiers identification.


Assuntos
Frutas , Prunus persica , Processamento de Imagem Assistida por Computador , Análise dos Mínimos Quadrados , Modelos Lineares
19.
Water Sci Technol ; 85(2): 617-632, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35100143

RESUMO

Sludge retention time (SRT) regulation is one of the essential management techniques for refined control of the main-sidestream treatment process under the low ammonia density. It is indispensable to understand the effect of SRTs changes on the Nitrifier kinetics to obtain the functional separation of the Nitrifier and the refined control of the nitrification process. In this study, Nitrifier was cultured with conditions of 35 ± 0.5 °C, pH 7.5 ± 0.2, DO 5.0 ± 0.5 mg-O/L, and SRTs were controlled for 40 d, 20 d, 10 d, and 5 d. The net growth rate (µm), decay rate (b), specific growth rate (µ), the yield of the Nitrifier (YA), temperature parameter (TA), and inhibition coefficient (KI) have been measured and extended with the SRT decreases. Instead, the half-saturation coefficient (KS) decreased. In addition, the limited value of pH inhibition occurs (pHUL), and the pH of keeping 5% maximum reaction rate (pHLL) was in a relatively stable state. The trade of kinetics may be induced by the change of species structure of Nitrifier. The Nitrosomonas proportion was increased, and the Nitrospira was contrary with the SRT decreasing. It is a match for the functional separation of Nitrifier when SRTs was 20 d at ambient temperature under the low ammonia density. The kinetics of ammonia-oxidizing organisms (AOO) and nitrite-oxidizing organisms (NOO) in Nitrifier under different SRT conditions should be measured respectively to the refined control of the partial nitrification process in future study.


Assuntos
Amônia , Esgotos , Reatores Biológicos , Cinética , Temperatura
20.
Environ Technol ; 43(23): 3507-3518, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33908820

RESUMO

The performance and energy consumption of a gas-liquid-solid inverse fluidised bed bioreactor (GLS-IFBBR) using polyethylene (PE) particles with different surface coatings (zeolite, lava rock, activated carbon and multi-plastic) as media for synthetic wastewater treatment were investigated at loading rates of 1.64-3.38 kg COD/(m3·d) and 0.17-0.34 kg N/(m3·d) to determine the optimum carrier media. The results showed that PE coated with other inorganic materials could increase the nutrient removal efficiency at the same influent conditions. Compared with other media, PE coated with zeolite (PEZ) was the optimal carrier particles in this study as reflected by the highest COD and nitrogen removal, stable effluent, low biomass yield at different hydraulic retention times (HRT). In addition, the energy consumption of lavarock-coated PE (PEL) with a highest density was the lowest.


Assuntos
Purificação da Água , Zeolitas , Reatores Biológicos , Nitrogênio , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos
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