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1.
Front Cell Dev Biol ; 9: 766142, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722550

RESUMO

As an evolutionarily conserved cellular process, autophagy plays an essential role in the cellular metabolism of eukaryotes as well as in viral infection and pathogenesis. Under physiological conditions, autophagy is able to meet cellular energy needs and maintain cellular homeostasis through degrading long-lived cellular proteins and recycling damaged organelles. Upon viral infection, host autophagy could degrade invading viruses and initial innate immune response and facilitate viral antigen presentation, all of which contribute to preventing viral infection and pathogenesis. However, viruses have evolved a variety of strategies during a long evolutionary process, by which they can hijack and subvert host autophagy for their own benefits. In this review, we highlight the function of host autophagy in the key regulatory steps during viral infections and pathogenesis and discuss how the viruses hijack the host autophagy for their life cycle and pathogenesis. Further understanding the function of host autophagy in viral infection and pathogenesis contributes to the development of more specific therapeutic strategies to fight various infectious diseases, such as the coronavirus disease 2019 epidemic.

2.
Geriatr Orthop Surg Rehabil ; 12: 21514593211043990, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34659869

RESUMO

Introduction: Previous clinical studies have reported associations between the acromion index, lateral acromion angle, and critical shoulder angle and the occurrence of rotator cuff tears. The objective of this study was to analyze the correlations of these different anatomic parameters in geriatric Chinese Population. Methods: Healthy geriatric Chinese participants (n = 66) and geriatric Chinese patients with rotator cuff tears (n = 70) identified between January 2019 and October 2020 were included in this study. Standardized true anteroposterior radiographs were used to measure the acromion index, lateral acromion angle, and critical shoulder angle in each study participant. Results: The mean acromion index was significantly larger, the mean lateral acromion angle was significantly smaller, and the mean critical shoulder angle was significantly larger in geriatric patients with full-thickness rotator cuff tears compared with geriatric healthy participants. Conclusion: There were a negative linear relationship between the acromion index and lateral acromion angle and a positive linear relationship between the acromion index and critical shoulder angle in geriatric patients with rotator cuff tear and geriatric healthy participants; we termed this phenomenon "Hypothesis of Acromion Index." The acromion index, lateral acromion angle, and critical shoulder angle are independent predictors of rotator cuff tears in a geriatric Chinese population.

3.
Bioresour Technol ; 341: 125871, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34523563

RESUMO

High concentration of NH4+-N in food waste digestate (FWD) produced from biological treatment of food waste is considered as a major threat on the composting process resulting in production of immature compost. Hence, a laboratory batch composting study was conducted to examine the feasibility of using biochar as a physical additive to ameliorate the inhibitory effect of NH4+-N and to mitigate the nitrogen loss during FWD composting. FWD was co-composted with tobacco biochar at a dosage of 0%, 2.5%, 5% or 10% (dw) in bench-scale composters with a controlled aeration system. The addition of 10% biochar enhanced the degradation rate resulting in 44% higher carbon decomposition than the control. Besides, 10% biochar amendment reduced NH3 and N loss by 58% and 5%, respectively and significantly reduced NH4+-N content to HKORC limit of < 700 mg/kg dw within 5 days showing the beneficiary impact of biochar addition.


Assuntos
Compostos de Amônio , Compostagem , Eliminação de Resíduos , Carvão Vegetal , Alimentos Fortificados , Cinética , Nitrogênio/análise , Solo
4.
Bioresour Technol ; 341: 125759, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34461407

RESUMO

Direct land application of food waste digestate (FWD) leads to 60-70% of nitrogen loss through NH3 volatilization due to its innate characteristics like high ammonium nitrogen (NH4+-N) (~6000 mg/kg dry matter) and high moisture content (~75%). Hence, bio stabilization of FWD through composting is a promising solution to curb the environmental and occupational hazards. Hence the aim of this study was to assess the feasibility of using sawdust and/or mature compost as a bulking agent to achieve effective composting. The results showed that mixing of FWD with sawdust alone or together with mature compost could produce quality compost with reduced NH4+-N (<700 mg/kg dry matter) and increased seed germination index (>80%) within 2 weeks of co-composting. Composting FWD with both sawdust and mature compost effectively reduced ~ 83% of NH3 volatilization demonstrating that this approach can effectively produce mature nitrogen enriched FWD compost.


Assuntos
Compostagem , Eliminação de Resíduos , Alimentos , Nitrogênio/análise , Solo , Madeira/química
5.
Bioresour Technol ; 337: 125384, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34186331

RESUMO

In this research, we investigated and compared the effects of three widely used conductive materials, e.g., zero-valent iron (Fe0), magnetite (Fe3O4), and biochar on the performance, stability, and in-depth mechanism during the anaerobic co-digestion process of sewage sludge and food waste. Among the three conductive materials, Fe0 could achieve the highest cumulative methane production of 394.0 mL/g volatile solids (VS) added, which was 1.24-fold and 1.17-fold higher than that receiving Fe3O4 and biochar. The mechanistic studies indicated that compared to the Fe3O4 and biochar groups, Fe0 could significantly enhance the release of soluble protein, polysaccharide, and dissolved organic matters, the degradation of volatile fatty acids and VS, and the activities of key enzymes and direct interspecies electron transfer (DIET). Consequently, the methane yield and digestate dewaterability were notably improved. Collectively, these findings will offer suggestions of the preferable conductive materials in the anaerobic co-digestion process for decision makers.


Assuntos
Eliminação de Resíduos , Esgotos , Anaerobiose , Reatores Biológicos , Digestão , Alimentos , Metano
6.
Bioresour Technol ; 334: 125032, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33964812

RESUMO

Food waste digestate is a by-product of the anaerobic digestion of food waste. Presence of high ammonium nitrogen content significantly increase the nitrogen loss upon direct application on soil or by conventional composting. In this review, a comprehensive discussion regarding the effective management of food waste digestate is outlined, in which global food waste digestate production, characteristics, and composting are discussed. The nitrogen dynamics cycle considering high ammonium nitrogen content in the digestate is also evaluated, including ammonification, nitrification, denitrification, and other possible mechanisms based on the current literature. Mitigation strategies for reducing nitrogen loss via C/N ratio adjustment and the addition of physical, chemical, and microbial amendments were evaluated and estimated for 15 countries based on the available data on food waste anaerobic digestion plants. Reduced nitrogen loss and high quality compost could be produced from food waste digestate by adapting mitigation strategies.

7.
Environ Res ; 197: 111093, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33812872

RESUMO

Understanding the interactions between magnetic particles (MPs) and polyaluminum chloride (PACl) is essential to elucidate the magnetic seeding coagulation (MSC) process. However, little is known about how MPs interact with the different Al species coexisting in the PACl. Here, the relationships among pollutants removal, residual Al distribution, and floc properties were comparatively studied in the MSC and traditional coagulation (TC) processes to address this issue. The response surface analysis indicated that the interaction between PACl and MPs dosages exhibited significant effects on turbidity and DOC removal. Negligible changes of dissolved Al after MPs addition indicated the weak connection between Ala and MPs. The formation of MPs-Alb-HA complexes resulted in the increase of turbidity removal from 90.2% to 96.0% and the reduction of colloidal Al from 0.67 to 0.30 mg L-1. Humic-like components could be adsorbed on MPs forming MPs-HA complexes, which enhanced the DOC removal from 55% to 58.5%. MPs addition produced loose flocs with a small floc fractal dimension value (1.74), so the average size and strength of flocs in the MSC process (425 µm and 49.7%) were lower than that in the TC process (464 µm and 58.3%). The cumulative volume percentage of large flocs (>700 µm) was decreased from 29.7% to 20.7% with MPs addition, indicating the disruption of large flocs and the reproduction of more fragments. The effective separation of these fragments by magnetic attraction maintained the efficient coagulation performance. This study provides new insights into the interaction mechanism of MPs and PACl in the MSC process.


Assuntos
Substâncias Húmicas , Purificação da Água , Hidróxido de Alumínio , Floculação , Substâncias Húmicas/análise , Caulim , Fenômenos Magnéticos
8.
Sci Total Environ ; 757: 143717, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33220995

RESUMO

Magnetic particles (MPs) assisted powdered activated carbon (PAC) is a promising composite material for adsorption removal of micropollutants. The fractional amount of Fe3O4 impacts the balance between adsorption capacity and magnetic property of magnetic activated carbons (MPACs), and therefore it affects the extent of sulfamethoxazole (SMX) removal. Here, five MPACs with different mass ratios of Fe3O4: PAC (1:1, 1:2, 1:4, 1:6, and 1:8) were prepared using a hydrothermal method and characterized by various spectroscopic methods. The spherical shaped MPs were monolayerly deposited on PAC with fewer pores blocked when the mass ratio of Fe3O4 was comparatively low (≤ 20%). MPAC6 (14.3 wt% of Fe3O4) had the best overall performance, with good Langmuir adsorption capacities for SMX (173.0 mg g-1) and excellent magnetic properties (9.0 emu g-1). Corresponding adsorption kinetics fitted well with the pseudo second-order kinetic model. The negative ΔG0 (-25.6 to -27.2 KJ mol-1) and ΔH0 (-9.14 KJ mol-1), and positive ΔS0 (0.55 KJ mol-1 K-1) properties indicated the spontaneous and exothermic nature of the adsorption process accompanied by an increase in entropy. The strong cation-assisted electron donor-acceptor and hydrophobic interactions were contributed to a high extent of SMX removal in the pH range of 2-4. Formation of negative charge-assisted H-bonds was responsible for the adsorption of hydrophilic SMX- on negatively charged MPAC6 in alkaline solution. Desorption and regeneration experiments showed SMX removal was still 92.3% in the 5th cycle. These findings give valuable insights into the interactions between SMX and MPACs and guide for choosing sustainable magnetic adsorbents for environmental applications.

9.
Chemosphere ; 268: 129363, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33360935

RESUMO

Magnetic seeding coagulation (MSC) process has been used to accelerate flocs sedimentation with an applied magnetic field, offering large handling capacity and low energy consumption. The interactions of three typical Al species, aluminum chloride (AlCl3), Al13O4(OH)247+ polymer (Al13), and (AlO4)2Al28(OH)5618+ polymer (Al30), with magnetic particles (MPs) were examined to clarify the MSC process. In traditional coagulation (TC) process, the aggregation of primary Ala-dissolved organic matter (DOM) complexes with in-situ-formed polynuclear species generated a large average floc size (226 µm), which was proved to be efficient for DOC removal (52.6%). The weak connections between dissolved Ala-DOM complexes and MPs led to the negligible changes of dissolved Al after seeding with MPs in AlCl3. A significant interaction between MPs and Al13 was observed, in which the MPs-Al13-DOM complexes were proposed to be responsible for the significant improvement of DOC removal (from 47% to 52%) and residual total Al reduction (from 1.05 to 0.27 mg Al L-1) with MPs addition. Al30 produced a lower floc fractal dimension (Df = 1.88) than AlCl3 (2.08) and Al13 (1.99) in the TC process, whereas its floc strength (70.9%) and floc recovery (38.5%) were higher than the others. Although more detached fragments were produced with MPs addition, the effective sedimentation of these fragments with the applied magnetic field led to the decrease of residual turbidity and colloidal Al in Al30. The dependence of coagulation behavior to MPs and different Al species can be applied to guide the application of an effective MSC process.


Assuntos
Purificação da Água , Alumínio , Cloreto de Alumínio , Floculação , Fenômenos Magnéticos , Polímeros
10.
Bioresour Technol ; 304: 122907, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32087548

RESUMO

The hydrophilic three-dimensional (3D) structure of graphene materials was produced with reducing agent-ethylene glycol through hydrothermal reduction. Numerous microorganisms with diverse community structure were established in anode surface, as the hydrophilicity of the graphene anode increased; more populations of Proteobacteria and Firmicutes families were identified in a higher hydrophilic anode. In addition, the start-up time of a microbial fuel cell (MFC) equipped with hydrophilic 3D graphene anode was only 43 h, which is much shorter than traditional 3D graphene-based anode systems. The most hydrophilic anode exhibited the maximal power density of 583.8 W m-3, 5 times larger than the least hydrophilic one. The content of oxygen in graphene materials improving hydrophilicity would play an important role in enhancing power density. This study proves that hydrophilic 3D graphene materials as the anode can improve MFC performance and start-up time.


Assuntos
Fontes de Energia Bioelétrica , Grafite , Eletrodos , Interações Hidrofóbicas e Hidrofílicas
11.
Biomaterials ; 238: 119829, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32058868

RESUMO

Magnesium (Mg)-based metals can be used as next-generation fracture internal fixation devices due to their specific properties. We used vascularized bone grafting fixed by degradable pure Mg screws and obtained satisfactory results in the treatment of osteonecrosis of the femoral head. However, the mechanical properties of these screws make them weaker than those made of traditional metals. In particular, one of the main challenges of using screws made of Mg-based metals is their application in fixation at important weight-bearing sites in the human body. Femoral neck fracture is a common clinical injury. In this injury, the large bearing stress at the junction requires a fixation device with extremely high mechanical strength. Surgery and appropriate internal fixation can accelerate the healing of femoral neck fractures. Traditional internal fixation devices have some disadvantages after surgery, including stress shielding effects and the need for secondary surgery to remove screws. On the basis of previous work, we developed high-strength pure Mg screws for femoral neck fractures. In this study, we describe the first use of high-purity Mg to prepare large-size weight-bearing screws for the fixation of femoral neck fractures in goats. We then performed a 48 weeks follow-up study using in vivo transformation experiments. The results show that these biodegradable high-purity Mg weight-bearing screws had sufficient mechanical strength and a degradation rate compatible with bone repair. Furthermore, good bone formation was achieved during the degradation process and reconstruction of the bone tissue and blood supply of the femoral head and femoral neck. This study provides a basis for future research on the clinical transformation of biodegradable high-purity Mg weight-bearing screws.


Assuntos
Fraturas do Colo Femoral , Parafusos Ósseos , Fraturas do Colo Femoral/cirurgia , Seguimentos , Fixação Interna de Fraturas , Consolidação da Fratura , Humanos , Magnésio , Suporte de Carga
12.
Medicine (Baltimore) ; 98(13): e14933, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30921190

RESUMO

The present study aimed to explore genetic association of receptor activator nuclear factor κB (RANK) polymorphisms with individual susceptibility to knee osteoarthritis (OA) in different Kellgren-Lawrence (KL) grades.This case-control study included 138 knee OA patients and 145 healthy individuals. RANK rs1805034 and rs8086340 polymorphisms were genotyped through polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The effects of RANK polymorphisms on knee OA risk were analyzed via χ test or Fisher exact test, and the results were expressed using odds ratios (ORs) with corresponding 95% confidence intervals (CIs).The C allele of rs1805034 polymorphism had significantly higher frequency in knee OA patients than in controls (P = .044), indicating that this allele could increase the risk of knee OA (OR = 1.424, 95% CI = 1.010-2.008). Besides, the CC genotype and C allele of the rs1805034 polymorphism were significantly associated with elevated risk of knee OA in moderate grade (CC vs TT: P = .018, OR = 3.071, 95% CI = 1.187-7.941; C vs T: P = .012, OR = 1.787, 95% CI = 1.131-2.823). However, rs8086340 polymorphism had no significant association with knee OA riskThe C allele of RANK rs1805034 polymorphism is closely correlated with increased risk of knee OA, especially for moderate grade.


Assuntos
NF-kappa B/genética , Osteoartrite do Joelho/genética , Polimorfismo de Nucleotídeo Único/genética , Receptor Ativador de Fator Nuclear kappa-B/genética , Adulto , Idoso , Alelos , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/classificação , Osteoartrite do Joelho/diagnóstico por imagem , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição/genética , Fatores de Risco
13.
Chin Med J (Engl) ; 130(11): 1261-1268, 2017 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-28524823

RESUMO

BACKGROUND: The prevalence of developmental dysplasia of the hip (DDH) is unknown in China. We aimed to determine the prevalence of DDH in Chinese adults. METHODS: In this study, we performed a cross-sectional survey of a nationally representative sample of Chinese adults. All participants underwent questionnaire investigation, physical examination, and X-ray examination. Factors associated with DDH were analyzed with logistic regression. RESULTS: We invited 29,180 individuals aged 18 years and over to participate, randomly selected from 18 primary sampling units (street districts in urban areas and townships in rural areas). The survey and examination were completed in 25,767 people (10,296 men and 15,471 women). DDH was diagnosed in 391 people, yielding an overall DDH prevalence of 1.52%. Based on this information, we estimate the number of individuals with DDH in China to be approximately 16.05 million. DDH prevalence increased with age (odds ratio = 1.53 [1.03-2.27], P = 0.036), was significantly higher among women than men (2.07% vs. 0.75%, P< 0.001), and was higher among rural residents than urban residents (1.75% vs. 1.29%, P< 0.001). Economic development was independently associated with the presence of DDH. There was no evidence of an association between body mass index alone, education, or current smoking or drinking and risk of DDH (P > 0.05). CONCLUSIONS: DDH has become an important public health problem. Special attention should be paid to residents with DDH. Screening for DDH should be performed in China.


Assuntos
Luxação Congênita de Quadril/epidemiologia , Adulto , Distribuição por Idade , Idoso , Índice de Massa Corporal , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Fatores de Risco , Distribuição por Sexo
14.
Chemosphere ; 174: 764-773, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28196685

RESUMO

The geochemical compositions of sediments in the Dongshan Bay, a semi-enclosed bay on the southeast coast of China, were obtained to identify pollutant sources and evaluate the anthropogenic impacts over the last 100 years. The results indicated that the metal flux had been increasing since the 1980s. Enrichment factor values (Pb, Zn and Cu) suggested only slight enrichment. The proportion of anthropogenic Pb changed from 9% to 15% during 2000-2014. Coal combustion might be an important contamination source in the Dongshan Bay. The historical variation in the metal flux reflected the economic development and urbanization in the Zhangjiang drainage area in the past 30 years. According to the Landsat satellite remote sensing data, the urbanization area expanded approximately three times from 1995 to 2010. The δ13C values (-21‰ to -23‰) of the organic matter (OM) in the sediments indicated that the OM was primarily sourced from aquatic, terrigenous and marsh C3 plants. Nitrogen was mainly derived from aquatic plants and terrigenous erosion before the 1980s. However, the total organic carbon (TOC) contents, total nitrogen (TN) contents and δ15N had been increasing since the 1980s, which suggested that the sources of nitrogen were soil erosion, fertilizer and sewage. In addition, the TOC and TN fluxes in the Dongshan Bay had significantly increased since the 1980s, which reflected the use of N fertilizer. However, the TOC and TN fluxes significantly decreased in the past decade because environmental awareness increased and environmental protection policies were implemented.


Assuntos
Baías/química , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , China , Fertilizantes/análise , Humanos , Metais Pesados/análise , Nitrogênio/análise , Esgotos/química
15.
Arthroscopy ; 33(2): 297-304, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28034486

RESUMO

PURPOSE: To biomechanically compare the stability between open repair and arthroscopic transosseous repair technique for reattachment of the foveal triangular fibrocartilage complex (TFCC). We also evaluated the feasibility of a new aiming device for the creation of 2 bone tunnels simultaneously during the arthroscopic technique. METHODS: Six matched pairs of fresh-frozen forearm cadaver specimens were prepared for testing. Group I specimens were treated by open repair with suture anchor. Group II specimens were treated by arthroscopic transosseous suture with a new aiming device. Before and after disruption of the TFCC fovea and after its repair, dorsal and palmar translation of the ulna was measured in both groups in response to a load (3 kg) applied in the palmar and then in the dorsal direction. The total translation of the ulna was calculated as the sum of the mean dorsal and palmar translations. RESULTS: The mean total ulnar translation before and after TFCC disruption, and after TFCC repair was 5.94 ± 2.16 mm, 9.08 ± 2.64 mm, and 6.04 ± 2.18 mm, respectively. The specimens demonstrated a significant increase in the total translation of the ulna after disruption of the ulnar attachment of TFCC (P = .003), whereas a significant decrease was observed after TFCC foveal repair (P = .003). The median percentage of eliminated translation after TFCC repair was 64% and 172%, respectively, in groups I and II (P = .043). CONCLUSIONS: The athroscopic transosseous suture technique demonstrated superior repair efficacy to the open repair technique in terms of biomechanical strength. This cadaveric study also demonstrated the feasibility of a new aiming device. CLINICAL RELEVANCE: When making decisions about TFCC foveal repair, arthroscopic transosseous suture technique may provide better biomechanical strength than the open repair technique.


Assuntos
Artroscopia , Instabilidade Articular/cirurgia , Fibrocartilagem Triangular/cirurgia , Articulação do Punho/cirurgia , Idoso , Fenômenos Biomecânicos , Cadáver , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Âncoras de Sutura , Técnicas de Sutura
16.
Bioresour Technol ; 168: 167-72, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24703958

RESUMO

To improve anaerobic digestion efficiency, combination pretreatment of alkaline and high pressure homogenization was applied to pretreat sewage sludge. Effect of alkaline dosage on anaerobic sludge digestion was investigated in detail. SCOD of sludge supernatant significantly increased with the alkaline dosage increase after the combined pretreatment because of sludge disintegration. Organics were significantly degraded after the anaerobic digestion, and the maximal SCOD, TCOD and VS removal was 73.5%, 61.3% and 43.5%, respectively. Cumulative biogas production, methane content in biogas and biogas production rate obviously increased with the alkaline dosage increase. Considering both the biogas production and alkaline dosage, the optimal alkaline dosage was selected as 0.04 mol/L. Relationships between biogas production and sludge disintegration showed that the accumulative biogas was mainly enhanced by the sludge disintegration. The methane yield linearly increased with the DDCOD increase as Methane yield (ml/gVS)=4.66 DDCOD-9.69.


Assuntos
Pressão , Eliminação de Resíduos/métodos , Esgotos/microbiologia , Hidróxido de Sódio/farmacologia , Anaerobiose/efeitos dos fármacos , Biocombustíveis , Análise da Demanda Biológica de Oxigênio , Concentração de Íons de Hidrogênio
17.
Huan Jing Ke Xue ; 32(2): 375-83, 2011 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-21528557

RESUMO

The variations in the concentration and distribution of nutrients and influencing factors in the Minjiang Estuary with a tidal cycle were investigated based on the data obtained during field observations in May 2007. The results showed the suspended sediment, dissolved inorganic nitrogen and silicate were opposite to the change of tidal, while the water level and salinity were consistent with tidal. The buffer mechanism of phosphate was controlled by suspended sand and water. The concentrations of silicate, phosphate and inorganic nitrogen were ranged 0.63-9.00 mg/L, 0.013-0.075 mg/L, 0.33-4.24 mg/L respectively. The contents of dissolved inorganic nitrogen in water mass increased remarkably comparing 1980s because of agriculture, industry and living. The research indicated that the nitrate and silicate were conservative, but phosphate was non-conservative in the biogeochemical processes of nutrients in Minjiang Estuary. The diluted water carried abundant inorganic nitrogen, silicate nutrients to Minjiang Estuary and thus phosphate was similar between diluted water and sea water. Based on the results of nutrient ratios, it was suggested that phosphate was a limiting factor for phytoplankton growth in the Minjiang Estuary.


Assuntos
Sedimentos Geológicos/análise , Nitrogênio/análise , Fósforo/análise , Rios/química , China , Nitrogênio/química , Oceanos e Mares , Fósforo/química , Água do Mar/química , Silicatos/análise , Silicatos/química
18.
Huan Jing Ke Xue ; 31(6): 1450-8, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20698255

RESUMO

Based on the inductively coupled plasma mass spectroscopy (ICP-MS) data of concentrations of 7 heavy metals (including Cr, Ni, Cu, Zn, Cd, Pb and As) in suspended particles and surface sediments samples collected at 6 and 1 13-hours-mooring stations, respectively, in Quanzhou Bay 4 days after the landing of typhoon "Fung-wong". The average contents of Cr, Ni, Cu, Zn, As, and Cd are 60.4, 50.3, 26.5, 101.7, 3.36, 40.0 and 0.180 microg/g, respectively, in the surface sediments, and are 1.108-7.408, 0.476-3. 394, 0.809-5.046, 3.190-19.337, 0.087-0.595, 2.621-10.073 microg/L and 4.160-50.828 ng/L, respectively, in different stations in the suspended particles. The contents and distribution patterns of 7 heavy metals during a tidal cycle were significantly changed after typhoon "Fung-wong" by contrasting with that in same stations and tidal time at an ordinary situation. The contents of heavy metals, besides Ni, evidently decreased but the distribution patterns were similar with that in an ordinary condition with relatively large grads after typhoon "Fung-wong" in the surface sediments at station Q4. While in the suspended particles, the contents of heavy metals were evidently increased with the distribution patterns varied obviously and differently due to their geographical position after typhoon "Fung-wong". These impacts of typhoon "Fung-wong" to the contents and distribution patterns of heavy metals could be attribute to the "second contamination" and the increased supply of particles materials from continent during the typhoon process. The results of this study provide a reference to accurate assessing and scientific governing the heavy metals' contamination, and provide a directly support to evaluating the integrated impacts of typhoon process on the contamination of heavy metals in the Quanzhou Bay.


Assuntos
Tempestades Ciclônicas , Monitoramento Ambiental , Metais Pesados/análise , Água do Mar/análise , Poluentes Químicos da Água/análise , China , Sedimentos Geológicos/análise , Espectrometria de Massas/métodos , Tamanho da Partícula
19.
Huan Jing Ke Xue ; 31(5): 1167-75, 2010 May.
Artigo em Chinês | MEDLINE | ID: mdl-20623847

RESUMO

Based on the inductively coupled plasma mass spectroscopy (ICP-MS) data of concentrations of 7 heavy metals (including Cr, Ni, Cu, Zn, Cd, Pb and As) in suspended particles and surface sediments samples collected at 6 and 2 13-hours-mooring stations, respectively, in Quanzhou Bay. The average contents of Cr, Ni, Cu, Zn, As, Pb, and Cd are 1.610-0.359, 0.730-0.150, 2.249-0.319, 6.421-1.266, 0.131-0.027, 4.176-1.101 microg/L and 17.526-2.260 ng/L, respectively, in different stations in the suspended particles and are 65.3-82.6, 37.8-39.8, 37.4-51.4, 121.0-172.8, 3.3-3.4, 42.2-76.9 and 0.217-0.493 microg/g, respectively, in the surface sediments of two stations. The concentrations of heavy metals in suspended particles varied significantly and the distribution patterns corresponded to the tidal and estuarine processes at the estuary area in a tidal cycle. While at the outer area, the varieties of concentrations were relatively unobvious and the re-suspension from surface sediments might play a significant role on distribution patterns of heavy metals in suspended particles. In a tidal cycle, the varieties of heavy metals concentrations in surface sediments were corresponding to that in suspended particles', which indicated that exchanges of heavy metals existed between surface sediments and suspended particles. These study results provide a reference to comprehensive understanding on distribution, migration and exchange of heavy metals in the Quanzhou Bay.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , China , Oceanos e Mares , Tamanho da Partícula
20.
Huan Jing Ke Xue ; 31(4): 931-8, 2010 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-20527173

RESUMO

The concentrations of 7 heavy metals were determined in 48 surface sediments in the Quanzhou Bay by an inductively coupled plasma mass spectroscopy (ICP-MS). The average contents of Cr, Ni, Cu, Zn, As, Cd and Pb are 47.66, 52.2, 30.86, 111.6, 5.29, 0.399 and 50.3 microg x g(-1), respectively. The Cd, Pb, Zn and As were mainly discharged into the Quanzhou Bay by Jinjiang River, while the materials near the Bay might supply a considerable amount of Cr, Ni and Cu. The result of the multi-analysis ecological risk index analyses revealed that Cr, Ni, Cu, Zn, Pb and As were moderately contaminated and presented low potential ecological risk, while Cd was heavily contaminated and raised high potential ecological risk. In general, moderately contaminated and potential ecological risk were occurred in whole Quanzhou Bay with the dominated polluted metals were Ni and Cd. The heavily contaminated area was corresponded to the high potential ecological risk area, which located at the confluent area of Jinjiang River and Luoyangjiang River. From the results of this study, we conclude that the Quanzhou Bay has been heavily polluted by heavy metals, therefore much environmental control should be continued and strengthen to Quanzhou Bay and its adjacent areas.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Metais Pesados/análise , Água do Mar/análise , Poluentes Químicos da Água/análise , China , Poluição Ambiental/análise
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