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1.
Environ Sci Technol ; 58(8): 3800-3811, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38350025

RESUMEN

The growing global water crisis necessitates sustainable desalination solutions. Conventional desalination technologies predominantly confront environmental issues such as high emissions from fossil-fuel-driven processes and challenges in managing brine disposal during the operational stages, emphasizing the need for renewable and environmentally friendly alternatives. This study introduces and assesses a bioinspired, solar-driven osmosis desalination device emulating the natural processes of mangroves with effective contaminant rejection and notable productivity. The bioinspired solar-driven osmosis (BISO) device, integrating osmosis membranes, microporous absorbent paper, and nanoporous ceramic membranes, was evaluated under different conditions. We conducted experiments in both controlled and outdoor settings, simulating seawater with a 3.5 wt % NaCl solution. With a water yield of 1.51 kg m-2 h-1 under standard solar conditions (one sun), the BISO system maintained excellent salt removal and accumulation resistance after up to 8 h of experiments and demonstrated great cavitation resistance even at 58.14 °C. The outdoor test recorded a peak rate of 1.22 kg m-2 h-1 and collected 16.5 mL in 8 h, showing its practical application potential. These results highlight the BISO device's capability to address water scarcity using a sustainable approach, combining bioinspired design with solar power, presenting a viable pathway in renewable-energy-driven desalination technology.


Asunto(s)
Membranas Artificiales , Purificación del Agua , Purificación del Agua/métodos , Agua , Agua de Mar , Ósmosis , Cloruro de Sodio
2.
Rapid Commun Mass Spectrom ; 36(11): e9289, 2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35262246

RESUMEN

RATIONALE: Stable K isotope geochemistry is becoming an important tool for various applications. Developments in analytical methods for K isotopes based on multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) without collision cell will bring research capability of K isotopes to many existing MC-ICP-MS labs. METHODS: Stable K isotopes were analyzed without applications of "cold plasma" and collision cell on a Nu 1700 Sapphire high-resolution multicollector inductively coupled plasma mass spectrometer. A conventional dry and hot plasma setting is used for analysis to maintain high K sensitivity and signal stability, and high mass resolution was applied to provide interference-free shoulders of 39 K+ for isotopic measurement of 41 K/39 K ratios. 40 Ar+ ion beam generated in ICP was neutralized in the ion guide rail for the Daly detector. RESULTS: Under such operating conditions, an external reproducibility of <±0.1‰ (2 standard deviation) for 41 K/39 K is achieved for K solutions of 1 ppm or above. Tests were carried out to evaluate the influence of total K loading, K concentration and acid molarity mismatch, matrix effects, and 40 Ar+ and 40 Ar1 H+ tailing on K isotope analysis. We found that the accuracy of K isotope analysis can be compromised by concentration mismatch of sample and standard K, by 0.007‰ in δ41 K per 1% mismatch of K content. By contrast, mismatch of HNO3 molarity or existence of HCl in HNO3 exerts negligible influences on the analytical precision and accuracy of K isotope analysis. Furthermore, K isotope analytical results remain accurate when Na/K, Mg/K, Ca/K, Rb/K, V/K, and Cr/K ratios are below 3%. CONCLUSIONS: The high-precision K isotope analytical method reported here is robust for studies on K isotopic variations in geological, cosmochemical, and biological samples. The f41 K values of six international geostandards measured using our method are consistent with data measured using different analytical methods from other laboratories.


Asunto(s)
Isótopos , Gases em Plasma , Isótopos/análisis , Espectrometría de Masas/métodos , Reproducibilidad de los Resultados
3.
Comput Intell Neurosci ; 2021: 8829639, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33986794

RESUMEN

The structural engineering is subject to various subjective and objective factors, the deformation is usually inevitable, the deformation monitoring data usually are nonstationary and nonlinear, and the deformation prediction is a difficult problem in the field of structural monitoring. Aiming at the problems of the traditional structural deformation prediction methods, a structural deformation prediction model is proposed based on temporal convolutional networks (TCNs) in this study. The proposed model uses a one-dimensional dilated causal convolution to reduce the model parameters, expand the receptive field, and prevent future information leakage. By obtaining the long-term memory of time series, the internal time characteristics of structural deformation data can be effectively mined. The network hyperparameters of the TCN model are optimized by the orthogonal experiment, which determines the optimal combination of model parameters. The experimental results show that the predicted values of the proposed model are highly consistent with the actual monitored values. The average RMSE, MAPE, and MAE with the optimized model parameters reduce 44.15%, 82.03%, and 66.48%, respectively, and the average running time is reduced by 45.41% compared with the results without optimization parameters. The average RMSE, MAE, and MAPE reduce by 26.88%, 62.16%, and 40.83%, respectively, compared with WNN, DBN-SVR, GRU, and LSTM models.


Asunto(s)
Aprendizaje Profundo , Redes Neurales de la Computación , Ingeniería , Predicción
4.
Biol Trace Elem Res ; 186(2): 489-497, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29748930

RESUMEN

The present study aimed to evaluate the effect of fluoride (F) on spermatogenesis in male rats. F- at 50 and 100 mg/L was administered for 70 days, after which the testicular and epididymis tissues were collected to observe the histopathological structure under a light microscope. The ultrastructure of the testis and sperm was also examined via transmission electron microscopy. The apoptosis of spermatogenic cells was measured through terminal deoxynucleotidyl transferase dUTP nick end labeling staining. The expression of proliferation factors, namely, proliferating cell nuclear antigen (PCNA) and Ki-67, in the testicular and epididymis tissues, were assayed through immunohistochemistry. F- at 50 and 100 mg/L significantly damaged the structure of the testis and epididymis, and the testis and sperm ultrastructure exhibited various changes, including mitochondrial swelling and vacuolization, and apsilated and raised sperm membrane. F treatment significantly increased spermatogenic cell apoptosis in the testis. PCNA (P < 0.01) and Ki-67 (P < 0.01) also presented positive expression in the testis. By comparison, no significant changes occurred in the epididymis. In summary, excessive F intake results in spermatogenesis dysfunction by damaging the testicular structure and inducing spermatogenic cell apoptosis in male rats. The positive expression level of PCNA and Ki-67 was a good response to spermatogenesis dysfunction.


Asunto(s)
Fluoruros/toxicidad , Antígeno Ki-67/biosíntesis , Antígeno Nuclear de Célula en Proliferación/biosíntesis , Espermatogénesis/efectos de los fármacos , Testículo/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Inmunohistoquímica , Masculino , Microscopía Electrónica de Transmisión , Ratas Sprague-Dawley , Espermatozoides/efectos de los fármacos , Espermatozoides/metabolismo , Espermatozoides/ultraestructura , Testículo/metabolismo , Testículo/ultraestructura
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