Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
Chemosphere ; : 142801, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38992446

RESUMO

Global water pollution by various pollutants is becoming an urgent problem. The conversion of durian fruit waste into adsorbents can help to mitigate this issue. Transforming durian waste into adsorbents can reduce pollution risk from waste discharged directly into the environment, while also effectively eliminating existing contaminants. Here, this work explores the potential of durian fruit waste and supplies insights into the synthesis and application of durian fruit waste-derived adsorbents such as biosorbents, modified-biosorbents, biochars, activated carbons, and composites. Several factors affecting the adsorption process of pollutants and the mechanism how pollutants can be adsorbed onto durian fruit waste-derived adsorbents are elucidated. This review also analyzes some aspects of limitations and prospects of biosorbents derived from durian fruit waste. It is anticipated that the promising properties and applications of durian fruit waste-derived adsorbents open up a new field for water waste treatment.

2.
Environ Sci Pollut Res Int ; 31(30): 42640-42671, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38902444

RESUMO

The current work investigated emerging fields for generating and consuming hydrogen and synthetic Fischer-Tropsch (FT) fuels, especially from detrimental greenhouse gases, CO2 and CH4. Technologies for syngas generation ranging from partial oxidation, auto-thermal, dry, photothermal and wet or steam reforming of methane were adequately reviewed alongside biomass valorisation for hydrogen generation, water electrolysis and climate challenges due to methane flaring, production, storage, transportation, challenges and opportunities in CO2 and CH4 utilisation. Under the same conditions, dry reforming produces more coke than steam reforming. However, combining the two techniques produces syngas with a high H2/CO ratio, which is suitable for producing long-chain hydrocarbons. Although the steam methane reforming (SMR) process has been industrialised, it is well known to consume significant energy. However, coke production via catalytic methane decomposition, the prime hindrance to large-scale implementation of these techniques for hydrogen production, could be addressed by coupling CO with CO2 conversion to alter the H2/CO ratio of syngas, increasing the reaction temperatures in dry reforming, or increasing the steam content fed in steam reforming. Optimised hydrogen production and generation of green fuels from CO2 and CH4 can be achieved by implementing these strategies.


Assuntos
Dióxido de Carbono , Hidrogênio , Metano , Biocombustíveis
3.
Food Sci Biotechnol ; 31(13): 1679-1689, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36312997

RESUMO

This study aimed to evaluate the encapsulation of pomelo (Citrus grandis (L.) Osbeck) essential oils using the spray drying technique. The parameters of the process include concentration of maltodextrin (20-35% by wt%/wt%), concentration of essential oil (1-2.5% by wt%/wt%), inlet temperature of spray drying (120-180 °C), and feed flow rates (120-240 mL/h) were soundly examined. The utilization of suitable parameters as the concentration of maltodextrin at 30% (by wt%/wt%), the concentration of essential oil at 1.5% (by wt%/wt%), the inlet temperature of 140 °C, and feed flow rate of 120 mL/h showed the highest drying yields (90.05%), microencapsulation yield (75.59%), and microencapsulation efficiency (89.44%). TGA and DSC results verified higher stability of Citrus grandis essential oil after encapsulation. The encapsulation of pomelo essential oils maintained most of the major components in comparison with the non-encapsulated essential oils without any significant changing in powder-obtained quality. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01161-5.

4.
Jpn J Clin Oncol ; 52(7): 707-715, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35383373

RESUMO

BACKGROUND: Colorectal cancer is a leading cancer incidence and cause of death worldwide and in Vietnam. Although screening is considered an effective measure to prevent and control colorectal cancer, there is no such effort in Vietnam. METHODS: Between 01 January 2018 and 31 October 2019, a population-based colorectal cancer screening program was conducted in Hanoi, Vietnam. A health advocacy campaign and follow-up phone calls were used to enroll residents aged ≥40 years old to complete an immunochemical-fecal occult blood testing. Positive immunochemical-fecal occult blood testing was followed by a colonoscopy. We also conducted a systematic review of the colorectal cancer screening programs in the Asia-Pacific region that used similar approach by searching Ovid Medline and PubMed databases. RESULTS: During study period, 103 542 individuals among 672 742 eligible residents attended the screening of whom 81.5% participants finished immunochemical-fecal occult blood testing test and the positive rate was 6.1%. The coverage rate for immunochemical-fecal occult blood testing test was 11.9%. Among 2278 individuals who underwent colonoscopy, 3.5% were histologically diagnosed with cancer, 17.8% with advanced adenomas, and 23.1% with non-advanced adenomas. Males had significantly higher detection rate of advanced adenomas, cancer or ≥ two polyps/tumor than females (P < 0.0001). The systematic review showed that in two-step modality (i.e. immunochemical-fecal occult blood testing/fecal immunochemical test and colonoscopy), the test positive was from 4.1 to 10.6%. Once colonoscopy was performed subsequently, the rate of cancer among positive participants was from 1.7 to 16.4% and that of advanced adenomas was from 7.1 to 23.1%. CONCLUSION: We showed that the two-step modality is a promising strategy for colorectal cancer screening in Vietnam that might apply to similar settings with limited resources.


Assuntos
Adenoma , Neoplasias Colorretais , Adenoma/diagnóstico , Adulto , Ásia , Colonoscopia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Detecção Precoce de Câncer , Feminino , Humanos , Masculino , Programas de Rastreamento , Sangue Oculto , Vietnã/epidemiologia
5.
Cancer Control ; 28: 1073274821989320, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33517745

RESUMO

BACKGROUND: Data about the risk factors and pancreatic cancer in developing countries remain limited. We investigated for the first time the role of a number of risk factors (family cancer history, smoking, alcohol consumption, diabetes, inflammation disease, HBV infection) associated with pancreatic cancer among Vietnamese patients. METHODS: We included all patients hospitalized at 4 Northern Vietnamese hospitals (Vietnam National Cancer Hospital, Bach Mai, Viet Duc, Thai Nguyen) and diagnosed with pancreatic cancer during the period from 2017 to 2019. Risk factors of eligible patients were collected and assessed the associations using a matched control study and logistic regression model analysis. RESULTS: We identified 196 patients with diagnosis of pancreatic cancer of which 114 males and 82 females. The average age of the patient at the time of diagnosis was 58.28 years (standard deviation of 12.94, ranging from 25 to 87). Most of patients were diagnosed at advanced stage (85%). Smoking, diabetes, inflammation disease significantly increased the cancer risks (OR and 95% CI were 2.42 (1.38-4.37), 3.09 (1.54-6.68), 2.21 (1.42-3.45), respectively). HBV infection demonstrated a significant link with pancreatic cancer in univariate model (OR = 2.94 (1.08-9.36)), but not in multivariate model. However, cancer family history and alcohol drinkers did not show any significantly increased risk related to pancreatic cancer. CONCLUSIONS: Our finding showed smoking, diabetes, inflammation disease significantly increased the risk of pancreatic cancer in Vietnam.


Assuntos
Complicações do Diabetes , Neoplasias Pancreáticas/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Consumo de Bebidas Alcoólicas/efeitos adversos , Estudos de Casos e Controles , Países em Desenvolvimento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/etiologia , Fatores de Risco , Fumar/efeitos adversos , Vietnã
6.
Environ Chem Lett ; 19(3): 2127-2140, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33462541

RESUMO

Dwindling fossil fuels and improper waste management are major challenges in the context of increasing population and industrialization, calling for new waste-to-energy sources. For instance, refuse-derived fuels can be produced from transformation of municipal solid waste, which is forecasted to reach 2.6 billion metric tonnes in 2030. Gasification is a thermal-induced chemical reaction that produces gaseous fuel such as hydrogen and syngas. Here, we review refuse-derived fuel gasification with focus on practices in various countries, recent progress in gasification, gasification modelling and economic analysis. We found that some countries that replace coal by refuse-derived fuel reduce CO2 emission by 40%, and decrease the amount municipal solid waste being sent to landfill by more than 50%. The production cost of energy via refuse-derived fuel gasification is estimated at 0.05 USD/kWh. Co-gasification by using two feedstocks appears more beneficial over conventional gasification in terms of minimum tar formation and improved process efficiency.

7.
RSC Adv ; 11(12): 6614-6619, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35423220

RESUMO

We discovered an in situ auto-reduction method to embed silver nanoparticles onto a nanoporous carbon (NC) derived from the zeolitic imidazole framework-8 (ZIF-8), without any requirement of the reducing agents. The detailed analysis demonstrated the formation of Ag NPs by the replacement of the metallic Zn residue in the NC with Ag ions. The synthesized Ag@NC exhibited a superior catalytic activity toward the reduction reaction of 4-nitrophenol into 4-aminophenol.

8.
Environ Sci Pollut Res Int ; 28(45): 63448-63463, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32588305

RESUMO

The emergent occurrence of sulfonamide species involving sulfadiazine (SDZ) and sulfamethazine (SMZ) in aquatic systems can cause a wide range of potential risks; hence, remediation strategies need to be necessary. Here, we develop the novel metal-organic framework-derived nanocomposite, and apply for the adsorption of SDZ and SMZ antibiotics. To assess the best-fitting kinetic (pseudo first-order, pseudo second-order) and isotherm (Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Redlich-Peterson, Sips, Toth, and Khan) models, a series of numerous statistical analysis was performed. Numerous error functions including squares of the errors (SSE), hybrid fractional error function (HYBRID), Marquardt's percent standard deviation (MPSD), and mean relative error (MRE) were also analyzed to assess the linear and nonlinear models. The results indicated that both linear and nonlinear kinetic models were mostly fitted well with pseudo second-order models (Radj)2 > 0.97. Although linear kinetics gave better (Radj)2, error functions (MRE, SSE, HYBRID, and MPSD) were mostly higher than those of nonlinear kinetics. For adsorption isotherm, nonlinear Redlich-Peterson was the most compatible model with extremely high adjusted coefficients of determination (Radj)2 ~ 1.0000. While nonlinear Langmuir model gave relatively high (Radj)2 (0.9898-0.9960) and acceptable error functions, we found the considerable difference of error functions and parameters among four types of linear Langmuir (Types I, II, III, IV). The findings indicate potential errors as selecting one of linearized Langmuir types in equilibrium study. It is suggested that nonlinear models should be applied for better fitness.


Assuntos
Estruturas Metalorgânicas , Nanocompostos , Poluentes Químicos da Água , Adsorção , Antibacterianos , Concentração de Íons de Hidrogênio , Cinética , Sulfonamidas , Termodinâmica
9.
Eur J Prev Cardiol ; 27(1): 39-46, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31382808

RESUMO

AIMS: The aim of this study was to investigate whether the Western dietary guidelines on fruit and vegetable intake are associated with blood pressure parameters and hypertension among Vietnamese adults. METHODS: Participants included 1384 women and 1049 men aged 18-69 years from the 2015 Vietnam national survey on risk factors of non-communicable diseases. Associations between dietary intake score based on the Dietary Approaches to Stop Hypertension (DASH) guidelines and World Health Organization recommendations on fruit and vegetable consumption and blood pressure parameters and hypertension were evaluated by multivariate regression analyses. RESULTS: Approximately 17.0% and 40.1% of participants met the respective definitions of hypertension according to Joint National Committee 7 (JNC7) and 2017 American College of Cardiology/American Heart Association (ACC/AHA) Hypertension Guideline. Highest tertiles of DASH scores for fruit intake were significantly associated with increased blood pressure parameters, particularly in women. Hypertension was associated with DASH score for fruit intake with odds ratios and 95% confidence intervals for tertiles 2-3 versus tertile 1: 1.31 (0.98, 1.76) and 1.43 (1.05, 1.93) for JNC7; 1.26 (1.01, 1.58) and 1.31 (1.04, 1.66) for 2017 ACC/AHA guideline (all p-trend <0.05). No association with blood pressure parameters and hypertension was observed for DASH score for vegetable intake and meeting World Health Organization recommendations for fruit and vegetable intake. CONCLUSION: We found an unexpected positive association between DASH score for fruit intake and blood pressure parameters and hypertension among Vietnamese adults. More research is needed in this population to understand the relationship between vegetable and fruit intake with hypertension before a firm conclusion and recommendation are made.


Assuntos
Pressão Sanguínea , Dieta Saudável , Abordagens Dietéticas para Conter a Hipertensão , Frutas , Hipertensão/epidemiologia , Recomendações Nutricionais , Verduras , Adolescente , Adulto , Idoso , Estudos Transversais , Inquéritos sobre Dietas , Dieta Saudável/efeitos adversos , Abordagens Dietéticas para Conter a Hipertensão/efeitos adversos , Feminino , Frutas/efeitos adversos , Humanos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Hipertensão/prevenção & controle , Masculino , Pessoa de Meia-Idade , Valor Nutritivo , Prevalência , Medição de Risco , Fatores de Risco , Vietnã/epidemiologia , Adulto Jovem
10.
Environ Sci Pollut Res Int ; 26(27): 28106-28126, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31363978

RESUMO

The occurrence and fate of antibiotic compounds in water can adversely affect human and animal health; hence, the removal of such substrates from soil and water is indispensable. Herein, we described the synthesis method of mesoporous carbon (MPC) via the pyrolysis route from a coordination polymer Fe-based MIL-53 (or MIL-53, shortly). The MPC structure was analyzed by several physical techniques such as SEM, TEM, BET, FT-IR, VSM, and XRD. The response surface methodology (RSM) was applied to find out the effects of initial concentration, MPC dosage, and pH on the removal efficiency of trimethoprim (TMP) and sulfamethoxazole (SMX) antibiotics in water. Under the optimized conditions, the removal efficiencies of TMP and SMX were found to be 87% and 99%, respectively. Moreover, the adsorption kinetic and isotherm studies showed that chemisorption and the monolayer adsorption controlled the adsorption process. The leaching test and recyclability studies indicated that the MPC structure was stable and can be reused for at least four times without any considerable change in the removal efficiency. Plausible adsorption mechanisms were also addressed in this study. Because of high maximum adsorption capacity (85.5 mg/g and 131.6 mg/g for TMP and SMX, respectively) and efficient reusability, MPC is recommended to be a potential adsorbent for TMP and SMX from water media.


Assuntos
Sulfonamidas/química , Poluentes Químicos da Água/química , Adsorção , Antibacterianos/química , Carbono , Cinética , Estruturas Metalorgânicas , Modelos Químicos , Pirólise , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfametoxazol/química , Trimetoprima , Água
11.
R Soc Open Sci ; 6(5): 190058, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31218048

RESUMO

Herein, we described a tunable method for synthesis of novel hollow mesoporous carbon (MPC) via direct pyrolysis (800oC) of MIL-53 (Fe) as a self-sacrificed template. The structural characterization revealed a hollow, amorphous, defective and mesoporous MPC along with high surface area (approx. 200 m2 g-1). For the experiments of ibuprofen adsorption onto MPC, effects of contact time, MPC dosage, ionic strength, concentration and temperature were systematically investigated. The optimal conditions consisted of pH = 3, concentration 10 mg l-1 and dose of 0.1 g l-1 for the highest ibuprofen removal efficiency up to 88.3% after 4 h. Moreover, adsorption behaviour, whereby chemisorption and monolayer controlled the uptake of ibuprofen over MPC, were assumed. Adsorption mechanisms including H-bonding, π-π interaction, metal-oxygen, electrostatic attraction were rigorously proposed. In comparison to several studies, the MPC nanocomposite in this work obtained the outstanding maximum adsorption capacity (206.5 mg g-1) and good reusability (5 cycles); thus, it can be used as a feasible alternative for decontamination of ibuprofen anti-inflammatory drug from water.

12.
Chemosphere ; 227: 455-461, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31003130

RESUMO

Herein, a facile strategy to fabricate the novel manganese oxide-imprinted mesoporous carbons (MOPCx, x presents for pyrolysis temperature) was described via the direct pyrolysis of Mn2(BDC)2(DMF)2 (BDC = 1,4-benzenedicarboxylate, DMF = N,N-dimethylformamide) as a self-sacrificed template at various temperatures (x = 550, 750, and 950 °C). The characterization results demonstrated the existence of MnO embedded in carbon structures with different morphologies, and enhancing surface areas (249.86-294.67 m2/g) compared with their precursor (3.59 m2/g). For methylene blue adsorption experiments, the MOPC pyrolyzed at 950 °C (MOPC950) revealed the best candidate with maximum uptake capacity (124.1 mg/g), so far higher than other MOPCx and Mn2(BDC)2(DMF)2 materials. Finally, adsorption mechanisms involving H-bond, and π-π interaction were proposed via the chemisorption between surface functional groups (carboxyl, phenol, lactone, and base).


Assuntos
Carbono/química , Compostos de Manganês/química , Azul de Metileno/química , Óxidos/química , Adsorção , Carvão Vegetal/química , Fenol , Temperatura
13.
Cancer Epidemiol ; 59: 83-103, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30710841

RESUMO

There is currently no national cervical screening or HPV immunization program in Vietnam. This study aims to synthesize available data on the burden of disease and to project the burden of cervical cancer to 2049 if no major interventions are implemented. We reviewed published data sources on risk factors for HPV prevalence, high-grade lesions, cervical cancer incidence and mortality in Vietnam from 1990 to 2017. We then used the available data to project the number of new cervical cancer cases for the period 2013-2049. Data on cervical cancer incidence and mortality in Vietnam are limited; two Vietnamese cancer registries have been reported on by the International Agency for Research on Cancer, which cover urban populations representing ∼20% of the national population. The reported age-standardized cervical cancer incidence in Hanoi was 6.7 (1993-1997), compared to 28.8 and 14.1 per 100,000 women in Ho Chi Minh City (1995-1998 and 2009-2012, respectively). Cancer mortality data are not uniformly available from cancer registries or mortality surveys in Vietnam because cause of death has not been routinely ascertained. Based on available urban population registry data, estimated rates in the rural population, and forward projection of existing trends, we estimate that without any further intervention, the number of new cases will increase from 6930 (range 5671-8493) in 2012 to 8562 (range 5775-12,762) in 2049, giving a total of 379,617 (range 276,879-542,941) new cases over the period 2013-2049. These findings help underpin the case for the delivery of HPV vaccination and cervical screening in Vietnam, and support similar initiatives in other low- and middle-income countries.


Assuntos
Infecções por Papillomavirus/epidemiologia , Sistema de Registros , Neoplasias do Colo do Útero/epidemiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Prevalência , Fatores de Risco , População Rural , População Urbana , Neoplasias do Colo do Útero/etiologia , Neoplasias do Colo do Útero/mortalidade , Vietnã/epidemiologia , Adulto Jovem
14.
Water Sci Technol ; 75(9-10): 2047-2055, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28498117

RESUMO

The present study focused on the application of response surface methodology to optimize the fabrication of activated carbon (AC) from sugarcane bagasse for adsorption of Cu2+ ion. The AC was synthesized via chemical activation with ZnCl2 as the activating agent. The central composite design based experiments were performed to assess the individual and interactive effect of influential parameters, including activation temperature, ZnCl2 impregnation ratio and activation time on the AC yield and removal of Cu2+ ion from the aqueous environment. The statistically significant, well-fitting quadratic regression models were successfully developed as confirmed by high F- and low P-values (<0.0001), high correlation coefficients and lack-of-fit tests. Accordingly, the optimum AC yield and removal efficiency of Cu2+ were predicted, respectively, as 48.8% and 92.7% which were approximate to the actual values. By applying the predicted optimal parameters, the AC shows a surprisingly high surface area of around 1,500 m2/g accompanied by large pore volume and narrow micropore size at low fabrication temperature.


Assuntos
Celulose/química , Carvão Vegetal/química , Cloretos/química , Cobre/química , Saccharum/química , Poluentes Químicos da Água/química , Compostos de Zinco/química , Adsorção , Temperatura
15.
J Pain Symptom Manage ; 31(5): 431-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16716873

RESUMO

Little is known about the prevalence of cancer pain in many developing countries. We report a hospital-wide survey of pain in a tertiary cancer center in Hanoi, Vietnam. All inpatients and outpatients age 18 years or older were approached for participation in the study. Data were collected using the Brief Pain Inventory. Results showed a 70% response rate. Prevalence of moderate to severe pain was 50% (89/178), with 23% reporting severe ratings of pain at its "worst" and 33% reporting severe impairment in their ability to work due to pain. Only 1% and 40% reported total and partial pain relief from medications, respectively. This study is among the first to provide a representative view of pain in a tertiary cancer treatment center in Hanoi, Vietnam. The findings provide empirical support for the need for better programmatic efforts to improve relief of cancer pain in developing countries, including Vietnam.


Assuntos
Institutos de Câncer/estatística & dados numéricos , Neoplasias/epidemiologia , Dor/epidemiologia , Adulto , Idoso , Coleta de Dados , Países em Desenvolvimento/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/terapia , Manejo da Dor , Prevalência , Vietnã/epidemiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...