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1.
Shanghai Journal of Preventive Medicine ; (12): 494-499, 2023.
Artigo em Chinês | WPRIM | ID: wpr-978415

RESUMO

ObjectiveTo understand the distribution characteristics of soil metal pollution around an abandoned rare earth ore in Jiangxi and the health impact on the surrounding residents. MethodsAccording to the distribution of abandoned rare earth ore, the village was divided into mining and non-mining areas. The prevalence of chronic diseases among residents over 15 years old in the village was collected through a self-designed questionnaire. Twenty-three soil samples were collected. The contents of rare earth metals (including lanthanum, cerium, praseodymium, and neodymium) and heavy metals (including arsenic (metalloids), cadmium, and lead) in the soil samples were determined by inductively coupled plasma mass spectrometry (ICP-MS). ResultsThe metal content showed a cumulative increasing trend. One of the23 sampling sites showed mild cadmium pollution. Compared with non-mining farmland, the metal content of farmland soil around the abandoned rare earth mine was relatively higher. The residents' top six self-reported chronic diseases were hypertension, chronic bronchitis, diabetes, stroke, hyperlipidemia, and cataract. The prevalence of hypertension in mining area was higher than non-mining area (χ2=4.141, P=0.042). The main related factors for hypertension in residents were the increase in age (OR=14.576, 95%CI: 2.773‒76.605) and body mass index (OR=3.147, 95%CI: 1.121‒8.835). ConclusionAbandoned rare earth ore may have a potential impact on the health of surrounding residents.

2.
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 161-167, 2023.
Artigo em Chinês | WPRIM | ID: wpr-970732

RESUMO

Objective: To investigate the role of Keap1/Nrf2/HO-1 signaling pathway in liver injury induced by neodymium oxide (Nd(2)O(3)) in mice. Methods: In March 2021, forty-eight SPF grade healthy male C57BL/6J mice were randomly divided into control group (0.9% NaCl), low dose group (62.5 mg/ml Nd(2)O(3)), medium dose group (125.0 mg/ml Nd(2)O(3)), and high dose group (250.0 mg/ml Nd(2)O(3)), each group consisted of 12 animals. The infected groups were treated with Nd(2)O(3) suspension by non-exposed tracheal drip and were killed 35 days after dust exposure. The liver weight of each group was weighed and the organ coefficient was calculated. The content of Nd(3+) in liver tissue was detected by inductively coupled plasma mass spectrometry (ICP-MS). HE staining and immunofluorescence was used to observe the changes of inflammation and nuclear entry. The mRNA expression levels of Keap1, Nrf2 and HO-1 in mice liver tissue were detected by qRT-PCR. Western blotting was used to detect the protein expression levels of Keap1 and HO-1. The contents of catalase (CAT), glutathione peroxidase (GSH-Px) and total superoxide dismutase (T-SOD) were detected by colorimetric method. The contents of interleukin 1β (IL-1β), interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) were determined by ELISA. The data was expressed in Mean±SD. Two-independent sample t-test was used for inter-group comparison, and one-way analysis of variance was used for multi-group comparison. Results: Compared with the control group, the liver organ coefficient of mice in medium and high dose groups were increased, and the Nd(3+) accumulation in liver of mice in all dose groups were significantly increased (P<0.05). Pathology showed that the structure of liver lobules in the high dose group was slightly disordered, the liver cells showed balloon-like lesions, the arrangement of liver cell cords was disordered, and the inflammatory exudation was obvious. Compared with the control group, the levels of IL-1β and IL-6 in liver tissue of mice in all dose groups were increased, and the levels of TNF-α in liver tissue of mice in high dose group were increased (P<0.05). Compared with the control group, the mRNA and protein expression levels of Keap1 in high dose group were significantly decreased, while the mRNA expression level of Nrf2, the mRNA and protein expression levels of HO-1 were significantly increased (P<0.05), and Nrf2 was successfully activated into the nucleus. Compared with the control group, the activities of CAT, GSH-Px and T-SOD in high dose group were significantly decreased (P<0.05) . Conclusion: A large amount of Nd(2)O(3) accumulates in the liver of male mice, which may lead to oxidative stress and inflammatory response through activation of Keap1/Nrf2/HO-1 signal pathway. It is suggested that Keap1/Nrf2/HO-1 signal pathway may be one of the mechanisms of Nd(2)O(3) expose-induced liver injury in mice.


Assuntos
Camundongos , Masculino , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Interleucina-6/metabolismo , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Fígado/metabolismo , Metais Terras Raras , Transdução de Sinais , Superóxido Dismutase/metabolismo , RNA Mensageiro/metabolismo
3.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 148-156, 2022.
Artigo em Chinês | WPRIM | ID: wpr-940496

RESUMO

ObjectiveTo investigate the effects of micro-fertilizer containing rare earth of different types and concentrations on the growth,yield and quality of Angelica sinensis. MethodOn the basis of the single-factor randomized block design, the growth and index components of Angelica sinensis were determined with rare earth-containing nitrate and chloride micro-fertilizers of different concentrations as foliar fertilizers. ResultSpraying 0.8 g·mL-1 rare earth-containing chloride micro-fertilizer could increase the economic yield of A. sinensis, with the fresh yield per mu (1 mu≈667 m2) reaching 855.4 kg and the dry yield per mu 350.7 kg,which increased by 15.16% and 28.70% respectively compared with that in the control group CK1. Spraying 1.2 g·mL-1 rare earth-containing nitrate micro-fertilizer could promote the growth and development of A. sinensis and significantly increase the content of index components, with the plant height reaching 93.05 cm,the stem diameter 15.60 mm,the root diameter 16.10 mm,the main root length 36.5 cm,and the number of leaves 11.25 pieces per plant, which increased by 32.76%,31.98%,41.98%,53.36%,and 45.16%, respectively, compared with those in the control group CK2. Besides, the content of ferulic acid,volatile oil,ligustilide, and extract was 0.96%,0.41%,0.30% and 48.76%,respectively,which increased by 12.94%,17.14%,11.11%, and 12.07%,respectively,compared with that in the control group CK2. ConclusionSpraying 0.8 g·mL-1 rare earth-containing chloride micro-fertilizer and 1.2 g·mL-1 rare earth-containing nitrate micro-fertilizer can promote the growth and development of A. sinensis,improve the medicinal properties,and increase yield and quality. Rare earth-containing micro-fertilizers can be applied in the standardization of A. sinensis cultivation, which can change the production status of A. sinensis that depends on chemical fertilizers and single fertilization, and promote the green, organic and ecological cultivation of A. sinensis.

4.
Journal of Public Health and Preventive Medicine ; (6): 111-116, 2021.
Artigo em Chinês | WPRIM | ID: wpr-877101

RESUMO

Time resolved fluoroimmunoassay (TRFIA) is an immunoassay technology developed on the basis of the unique fluorescence properties of rare earth elements. TRFIA combines the advantages of radioimmunoassay, enzyme-linked immunoassay and common fluorescence immunoassay. It has high sensitivity, strong specificity, good stability, wider measurement range, long fluorescence life, simple operation and non-radiation, and shows a good prospect in the field of immunoassay. In this paper, several common TRFIA materials are discussed based on the latest research progress of time-resolved fluorescence in immunoassay. The application of TRFIA in immunodiagnosis, food detection, environmental monitoring and so on is elaborated, and its development direction and application are prospected.

5.
Nucleus (La Habana) ; (63): 6-8, Jan.-June 2018. tab
Artigo em Inglês | LILACS | ID: biblio-990199

RESUMO

Abstract The rare-earth nuclei have well-known collective properties. The theoretical description of these nuclei represents a challenge to nuclear models, due to the enormous dimensions of the valence space, making the problem unmanageable. This leads us to use symmetry-based models, where it is possible to calculate in a free-truncation environment. In this work we present results for the energy spectrum and the electromagnetic properties in even-even Yb isotopes using the pseudo-SU(3) shell model. The model considers a Nilsson Hamiltonian that additionally includes the quadrupole-quadrupole and pairing interactions, systematically parameterized. The results show that the model considered is a powerful theoretical tool, allowing us to describe the normal parity sector of deformed rare earth nuclei.


Resumen Las propiedades colectivas de los núcleos de las tierras raras están muy bien determinadas. La descripción teórica de estos núcleos representa un desafío para cualquier modelo nuclear debido a las dimensiones excesivas del espacio de valencia, lo que vuelve el problema inmanejable. Esto nos lleva a emplear modelos basados en simetrías, donde es posible realizar cálculos sin truncamiento del espacio. En este trabajo se presentan resultados para el espectro energético y las propiedades electromagnéticas en isótopos para-par de iterbio, utilizando el modelo de capas pseudo-SU(3). El modelo considera el hamiltoniano de Nilsson, al que adicionalmente se le han incluido las interacciones cuadrupolo-cuadrupolo y de apareamiento, parametrizadas de forma sistemática. El resultado muestra que el modelo utilizado es una herramienta poderosa que permite describir el sector de paridad normal del espectro de núcleos deformados de las tierras raras.

6.
Acta sci., Biol. sci ; 40: 38469-38469, 20180000. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460815

RESUMO

Rare earth elements, such as lanthanum (La), have been applied to agriculture via fertilizers, aiming to increase the productivity and crop quality, such results observed mainly in China. However, the knowledge about the effect of La on maize growth, as well as for other species, despite the growing interest it is still limited. The aim of this study was to evaluate the effects of La on maize growth, La content,photosynthetic rate and chlorophyll content in maize plants in response to La treatment (0, 25, 50, 100, 150, 300 and 600 μM) in nutrient solution for three weeks. The plants were placed in geminated pots using a split-root technique. One of the pots in the geminated set was filled with a complete nutrient solution without La, while another was filled with a nutrient solution without phosphorus but containing different concentrations of La. It was verified that roots of maize plants can accumulate approximately sixty percent more La than shoots. Moreover, low La concentrations stimulated an increase in chlorophyll index,resulting in a slight increase in shoot biomass. At higher levels, La didn’t reduce growth but caused adecrease in both photosynthetic rate and chlorophyll index.


Elementos terra rara, como lantânio (La), são aplicados à agricultura via fertilizantes, com oobjetivo de aumentar a produtividade e a qualidade das culturas agrícolas, fato observado principalmente naChina. Entretanto, o conhecimento sobre o efeito de La no crescimento do milho, bem como para outrasculturas agrícolas, ainda é limitado apesar do interesse crescente. O presente estudo objetivou avaliar oefeito da aplicação de La sobre o crescimento, teor de La, fotossíntese e teor de clorofila em plantas demilho, expostas a concentrações crescentes de La (0, 25, 50, 100, 150, 300 e 600 μM) em solução nutritivapor três semanas. As plantas foram colocadas em vasos geminados usando uma técnica de raiz divisória.Um dos potes no conjunto geminado foi preenchido com solução nutritiva completa que não continha La,enquanto outra foi preenchida com solução nutritiva sem fósforo, mas contendo diferentes concentraçõesde La. Foi verificado que as raízes das plantas de milho podem acumular sessenta por cento mais La quandocomparado à parte aérea. Além disso, as baixas concentrações de La estimularam o aumento do teor declorofila, resultando em um aumento na biomassa da parte aérea. Em concentrações mais elevadas, aaplicação de La não reduziu o crescimento das plantas de milho, mas causou diminuição na taxafotossintética e no índice de clorofila.


Assuntos
Clorofila/análise , Clorofila/biossíntese , Lantânio/análise , Lantânio/efeitos adversos , Zea mays/citologia , Zea mays/química , Clorofila
7.
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 99-101, 2018.
Artigo em Chinês | WPRIM | ID: wpr-806000

RESUMO

Objective@#To investigate the levels of lanthanum, cerium, praseodymium, and neodymium in the blood, urine, and hair samples from residents in the rare earth mining area of a city in China, and to provide a scientific basis for the control of rare earth pollution and the protection of population health.@*Methods@#A total of 147 residents who had lived in the rare earth mining area of a city for a long time were selected as the exposure group, and 108 residents in Guyang County of this city who lived 91 km away from the rare earth mining area were selected as the control group. Blood, urine, and hair samples were collected from the residents in both groups. Inductively coupled plasma mass spectrometry was used to determine the content of lanthanum, cerium, praseodymium, and neodymium in blood, urine, and hair samples.@*Results@#In the exposure group, the median levels of lanthanum, cerium, praseodymium, and neodymium were 0.854, 1.724, 0.132, and 0.839 μg/L, respectively, in blood samples, 0.420, 0.920, 0.055, and 0.337 μg/L, respectively, in urine samples, and 0.052, 0.106, 0.012, and 0.045 μg/g, respectively, in hair samples. The exposure group had significantly higher levels of the four rare earth elements in blood, urine, and hair samples than the control group (P<0.01) .@*Conclusion@#The residents in the rare earth mining area of this city have higher content of lanthanum, cerium, praseodymium, and neodymium in blood, urine, and hair than those in the non-mining area; the content of cerium is highest, followed by lanthanum, neodymium, and praseodymium.

8.
Chinese Medical Journal ; (24): 1591-1597, 2018.
Artigo em Inglês | WPRIM | ID: wpr-688073

RESUMO

<p><b>Background</b>Nanotechnology is emerging as a promising tool to perform noninvasive therapy and optical imaging. However, nanomedicine may pose a potential risk of toxicity during in vivo applications. In this study, we aimed to investigate the potential toxicity of rare-earth nanoparticles (RENPs) using mice as models.</p><p><b>Methods</b>We synthesized RENPs through a typical co-precipitation method. Institute of Cancer Research (ICR) mice were randomly divided into seven groups including a control group and six experimental groups (10 mice per group). ICR mice were intravenously injected with bare RENPs at a daily dose of 0, 0.5, 1.0, and 1.5 mg/kg for 7 days. To evaluate the toxicity of these nanoparticles in mice, magnetic resonance imaging (MRI) was performed to assess their uptake in mice. In addition, hematological and biochemical analyses were conducted to evaluate any impairment in the organ functions of ICR mice. The analysis of variance (ANOVA) followed by a one-way ANOVA test was used in this study. A repeated measures' analysis was used to determine any significant differences in white blood cell (WBC), alanine aminotransferase (ALT), and creatinine (CREA) levels at different evaluation times in each group.</p><p><b>Results</b>We demonstrated the successful synthesis of two different sizes (10 nm and 100 nm) of RENPs. Their physical properties were characterized by transmission electron microscopy and a 980 nm laser diode. Results of MRI study revealed the distribution and circulation of the RENPs in the liver. In addition, the hematological analysis found an increase of WBCs to (8.69 ± 0.85) × 10/L at the 28 day, which is indicative of inflammation in the mouse treated with 1.5 mg/kg NaYbF:Er nanoparticles. Furthermore, the biochemical analysis indicated increased levels of ALT ([64.20 ± 15.50] U/L) and CREA ([27.80 ± 3.56] μmol/L) at the 28 day, particularly those injected with 1.5 mg/kg NaYbF:Er nanoparticles. These results suggested the physiological and pathological damage caused by these nanoparticles to the organs and tissues of mice, especially to liver and kidney.</p><p><b>Conclusion</b>The use of bare RENPs may cause possible hepatotoxicity and nephritictoxicity in mice.</p>

9.
Chinese Journal of Analytical Chemistry ; (12): 757-764, 2018.
Artigo em Chinês | WPRIM | ID: wpr-692311

RESUMO

Pulsed glow discharge mass spectrometric(Pulsed-GDMS) method for the measurement of 7 kinds of key elements(Mg,Fe,Cu,La,Ce,Pr and Nd) in rare earth alloys was established. The influence factors of measurement repeatability, such as pulse time, sample homogeneity, anode cap, flow tube, corn, and sample tablet density were systematically studied. The results showed that,for elements with mass fraction of more than mg/g, the parts (anode cap, flow tube and corn) had the largest influence on measurement repeatability. When the new graphitic parts were used and no parts were changed during the whole measurement,the relative standard deviation (RSD) was less than 3%. However, the RSD were 2%-11%and 3%-21% when the new graphitic parts and the reusable parts were used and changed,respectively. The second influence factor of measurement repeatability was the tablet density. The results showed that,the lower the density,the worse the measurement repeatability, and for the dense tablet, the RSD was less than 3%. Key elements in 1# rare earth alloy were measured by high resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS), and the analytical results were used as reference values for the calibration of Pulsed-GDMS. The relative sensitivity factors (RSF) were obtained, and the key elements in 2# rare earth alloy were measured by Pulsed-GDMS after calibration. The analytical results of key elements in 2#sample by Pulsed-GDMS and HR-ICP-MS were compared, and the results showed that for the dense sample, the analytical results showed good agreement. Under the optimal conditions, the expanded uncertainty of measurement by Pulsed-GDMS reduced to 3%-10%.

10.
Chinese Journal of Analytical Chemistry ; (12): 1316-1322, 2017.
Artigo em Chinês | WPRIM | ID: wpr-609372

RESUMO

The concentrations and distributions of trace metals and rare earth elements (REE) in sediment and mussel samples collected from the India Ocean hydrothermal area were analyzed.The metal correlation between organisms and sediments was investigated, and the ecological and chemical characteristics of REE were also explored.The results showed that, the trace metals in sediments were mainly Fe (96.6 mg/kg), Mn (1.14 mg/kg) and Zn (322.6 μg/kg), and Fe had high ratio of 98.15% by normalized calculation, which indicated that the available sediments in this studying hydrothermal area mainly consisted of iron ore substances.Trace metals and REE distributions all had good correlation between deep-sea sediments and deep-sea mussels, and the correlation coefficients were 0.991 for trace metals and 0.996 for REE.The contents and distributions of metal elements in deep-sea mussels were different from those in offshore mussels.The REE distributions in sediments and mussels showed obvious fractionation phenomenon, and the enrichment of LREE in mussels was significant.Through the REE patterns, Eu and Gd in sediments and mussels all showed anomalies, and Eu had a significant abnormal phenomenon in deep-sea sediments and deep-sea mussels.Besides, δEu values were 9.50, 10.68 and 0.23 in deep-sea sediments, deep-sea mussels and offshore mussels, respectively, and δCe were 2.21, 2.71 and 4.38, which showed that the enrichment sources of REE in offshore mussels and deep-sea mussels were different, and the REE in sediments and mussels from the India Ocean were homologous.

11.
Chinese Journal of Analytical Chemistry ; (12): 1915-1920, 2017.
Artigo em Chinês | WPRIM | ID: wpr-663470

RESUMO

A label-free method for sensitive and selective detection of thrombin ( Tb) was constructed based on rare earth ion mediated fluorescence switch of graphene quantum dots ( GQDs) . Rare earth ion ( Er3+) can assemble onto the surface of GQDs through the coordination interaction between Er3+ ions and the carboxylate groups located on the surface or edge of the GQDs, resulting in the aggregation of the GQDs and thereby decrease of the fluorescence of the GQDs. In the presence of Tb, the oxygen and nitrogen-donor atoms in Tb can coordinate with Er3+ ions and compete with the carboxylate groups on GQDs to coordinate Er3+ ions, thus the interaction between GQDs and Er3+ ions is reduced, which lead to the restoration of the GQDs fluorescence. In this study, the sensing mechanism was demonstrated by transmission electron microscopy, atomic force microscope, Fourier transform infrared spectroscopy, UV-Vis absorption and fluorescence spectroscopy. The limit of detection for Tb assay was as low as 0. 049 nmol/L. Moreover, this assay was successfully applied to the selective determination of Tb in real samples.

12.
Chinese Journal of Analytical Chemistry ; (12): 1539-1546, 2016.
Artigo em Chinês | WPRIM | ID: wpr-504384

RESUMO

A total of 30 kunds of fush samples, 5 kunds of shellfush samples and 4 kunds of crustacean samples from the Nansha sea area of chuna were dugested by mucrowave dugestuon system wuth HNO3-H2 O2 as the dugestuon reagent. Then the contents ( ICP-MS determunatuon) and ecologucal chemucal characterustucs of rare earth elements ( REE) were studued. The results showed that the method of mucrowave dugestuon-ICP-MS for the determunatuon of rare earth elements was perfect, and the lunear relatuonshup for each element was good wuth r≥0 . 9997 . The detectuon lumut of the method could reach 1 . 0 ng/L wuth the relatuve standard devuatuon (RSD, n=3) of less than 5. 0%. The recoverues of rare earth elements were between 91. 50% and 106. 67%. The total amount of rare earth un fush samples, shellfush samples and crustacean samples were 5. 02-34. 8 μg/kg, 30. 4-1481 μg/kg and 103-863 μg/kg, respectuvely. The average enruchment contents of the rare earth un the 3 specues was crustacean > shellfush > fush. The contents of 14 rare earth elements un fush/shellfush/crustaceans showed sugnufucantly posutuve correlatuon ( r>0 . 80 ) . The contents of lught rare earth elements ( La-Eu) were hugher than that of heavy rare earth elements ( Gd-Lu) . The lught and heavy rare earth elements had obvuous fractuonatuon, and the REE dustrubutuon pattern was consustent un fush/shellfush/crustacean wuth Gd negatuve anomaly. The δEu values had negatuve anomalues, sumular to the δEu values un correspondung area sedument, and δCe values showed posutuve anomalues, whuch showed that Ce had dufferent process of oxudatuon and reductuon un the organusm and sedument deposutuon. At the same tume, the enruchment relatuonshup of rare earth elements un sedument and organusm was also studued. In thus study, the content and dustrubutuon of rare earth elements un the tropucal marune fush/shellfush/shellfush were analyzed, whuch could provude basuc data for the study of the level and mugratuon and accumulatuon of rare earth elements un the envuronment of the South Chuna Sea.

13.
Chinese Journal of Analytical Chemistry ; (12): 1359-1364, 2016.
Artigo em Chinês | WPRIM | ID: wpr-503549

RESUMO

A new method for accurate determination of 15 rare earth elements including Y-Lu in tea samples by inductively coupled plasma-mass spectrometry( ICP-MS) was proposed. Sample preparation was based on the modified oxygen flask combustion technique. By using quartz cloth coated with glycerol instead of filter paper as the ignition agent, a total amount of 0. 1 g sample could be completely burned in a 500-mL flask. Key factors affecting the sample preparation effect were systematically investigated, and it was found that the extraction efficiencies of over 90% for all the analytes could be realized with 5 mL of 4% HNO3+1% HF ( V/V) as the extractant for the combustion residue and the total extraction process could be finished in one minute under sonication, which resulted in a very fast sample preparation procedure that could be completed in less than 3 minutes. The relative standard deviations ( RSD) of six parallel determination values were between 2. 7% and 5. 5%, and the detection limits ranged from 0. 001 mg/kg to 0. 006 mg/kg. Three tea standard reference materials were analyzed with the method and the detection results agreed well with the standard values. The method was successfully applied to three real samples analysis.

14.
Biomedical and Environmental Sciences ; (12): 281-290, 2015.
Artigo em Inglês | WPRIM | ID: wpr-264587

RESUMO

<p><b>OBJECTIVE</b>The aim of this study was to assess the effects of yttrium nitrate on neurobehavioral development in Sprague-Dawley rats.</p><p><b>METHODS</b>Dams were orally exposed to 0, 5, 15, or 45 mg/kg daily of yttrium nitrate from gestation day (GD) 6 to postnatal day (PND) 21. Body weight and food consumption were monitored weekly. Neurobehavior was assessed by developmental landmarks and reflexes, motor activity, hot plate, Rota-rod and cognitive tests. Additionally, brain weights were measured on PND 21 and 70.</p><p><b>RESULTS</b>No significant difference was noted among all groups for maternal body weight and food consumption. All yttrium-exposed offspring showed an increase in body weight on PND 21; however, no significant difference in body weight for exposed pups versus controls was observed 2 weeks or more after the yttrium solution was discontinued. The groups given 5 mg/kg daily decreased significantly in the duration of female forelime grip strength and ambulation on PND 13. There was no significant difference between yttrium-exposed offspring and controls with respect to other behavioral ontogeny parameters and postnatal behavioral test results.</p><p><b>CONCLUSION</b>Exposure of rats to yttrium nitrate in concentrations up to 45 mg/kg daily had no adverse effects on their neurobehavioral development.</p>


Assuntos
Animais , Feminino , Masculino , Gravidez , Ratos , Relação Dose-Resposta a Droga , Poluentes Ambientais , Toxicidade , Inocuidade dos Alimentos , Aprendizagem em Labirinto , Atividade Motora , Medição da Dor , Efeitos Tardios da Exposição Pré-Natal , Distribuição Aleatória , Ratos Sprague-Dawley , Medição de Risco , Teste de Desempenho do Rota-Rod , Ítrio , Toxicidade
15.
Chinese Journal of Analytical Chemistry ; (12): 21-26, 2015.
Artigo em Chinês | WPRIM | ID: wpr-457747

RESUMO

A microwave digestion system was preparation for the digestion of the sediment samples of 16 stations in the Southe mid_Atlantic ridge by using HNO3_H2 O2_HF as the digestion reagent. The rare earth elements ( RE ) in sediments were determined by inductively coupled plasma mass spectrometry, and distribution characteristics of rare earth elements were studied. The microwave digestion_ICP_MS method was used for the determination of rare earth elements with a good linear relationship ( r=0 . 9997-1 . 0000 ) for each element. The detection limit reached ng/L level, the relative standard deviation ( RSD, n=3 ) was less than 3% and the relative error was 6%. The total amount of rare earth elements (ΣRE) in sediment samples from 16 stations varied in the range of 37. 25-134. 77 μg/g, the ratio range of light RE/heavy RE ( LRE/HRE) was 0 . 61-1 . 70 , the average value was 1 . 27 , and the enrichment of light rare earth elements in sediments was slightly obvious. The RE distribution patterns were basically the same in each station with obvious fractionation between LRE and HRE. The RE distribution patterns were also similar in sediments from different sources with slightly difference between terrestrial and marine sediments. The δEu and δCe in the sediments had negative anomaly which showed that the rare earth elements in sediments came from the seawater. This study first analyzed the content and distribution of rare earth elements in the southern Atlantic, providing data and technical support for further study of the distribution of rare earth elements in the Atlantic.

16.
Chinese Journal of Analytical Chemistry ; (12): 847-852, 2014.
Artigo em Chinês | WPRIM | ID: wpr-452277

RESUMO

A Ni-based rare-earth perovskite LaNiTiO3 nanoparticles was synthesized and its catalytic activity was investigated. Based on this, a simple and quick nonenzyme electrochemical sensor was fabricated with stable and reliable performances for the determination of hydrogen peroxide (H2 O2 ). The techniques of X-ray diffraction, FT-IR spectra, transmission electron microscopy, X-ray fluorescene spectroscopy and scan electronmicroscope were used to characterize the composition, structure and morphology of as-synthesized sample. The sensor based on this nanomaterial was investigated and optimized by cyclic voltammetry and current-time techniques. The results showed the working electrode modified with LaNiTiO3 (0. 5 g / L, 8. 0μL) in 0. 1 mol/ L NaOH exhibited good catalytic properties for H2 O2 . Under the optimum conditions, the sensor performed excellent properties, such as quick response time ( about 2 s ), a wide linearity (0. 2 μmol/ L -8. 0 mmol/ L), a low detection limit of 0. 05 μmol/ L ( S / N = 3 ), a high sensitivity of 957 μA (mmol/ L) -1 cm-2 , good reproducibility and anti-interference ability, which was better than those of some other biosensors reported recently. So, it may be used for the analysis and detection of H2 O2 in practical samples such as biomedicine.

17.
Chinese Journal of Radiological Medicine and Protection ; (12): 166-169, 2013.
Artigo em Chinês | WPRIM | ID: wpr-432970

RESUMO

Objective To obtain the concentrations and daily intakes of 15 rare earth elements in foods for adult men in four areas in China.Methods With duplicate portion study,120 mixed diet samples were collected from adult men in cities of Tianjin,Chengdu,Zhenjiang and Taiyuan,which belong to 4 areas with different dietary types in China.The concentrations of cerium,dysprosium,erbium,gadolinium,lanthanum,lutetium,holmium,neodymium,praseodymium,scandium,samarium,terbium,thulium,yttrium and ytterbium in these samples were determined by Inductively Coupled Plasma Mass Spectrometry(ICP-MS) after pretreatment,and the daily intakes of them were also calculated.Results The concentrations of 15 rare earth elements and their daily intakes in foods for adult men were obtained.Conclusions The concentrations of these elements in each area are consistent with normal distribution.The total rare earth element concentration in the diet of adult men ranges from 24.68 to 109.27 μg/g.The daily intake of total rare earth elements is about 24 μg/d.Reference values of the rare earth element concentrations in the diet and daily intake of Chinese adult men were updated.

18.
J Environ Biol ; 2012 Jul; 33(4): 689-693
Artigo em Inglês | IMSEAR | ID: sea-146757

RESUMO

Reconnaissance hydrochemical survey was conducted in some villages of Adilabad district, Andhra Pradesh to assess the quality of groundwater, which is mainly used for drinking purpose. The study consists of the determination of physico-chemical properties, trace metals, heavy metals and rare earth elements in water samples. The data showed the variation of the investigated parameters in samples as follows: pH 6.92 to 8.32, EC 192 to 2706 µS cm-1, TDS 129.18 to 1813.02 ppm. The pH of the waters was within the permissible limits whereas EC and TDS were above the permissible limits of World Health Organization (WHO). Total 27 elements (Li, Be, B, Na, Mg, Al, Si, K, Ca, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Sb, Ba and Pb) were analyzed using Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). The concentration of elements in water samples ranged between 0.063 to 0.611 mg l-1 for B, 11.273 to 392 mg l-1 for Na, 5.871 to 77.475 mg l-1 for Mg, 0.035 to 1.905 mg l-1 for Al, 0.752 to 227.893 mg l-1 for K, 11.556 to 121.655 mg l-1 for Ca and 0.076 to 0.669 mg l-1 for Fe respectively. The concentrations of Na, Mg, Al, K, Ca, and Fe exceeded the permissible limits of WHO and BIS guidelines for drinking water quality. In the present study, Bhimavaram, Kazipalli, Kannepalli and Chennur areas of the Adilabad are especially prone to geogenic contamination. Overall water quality was found unsatisfactory for drinking purposes.

19.
Artigo em Inglês | IMSEAR | ID: sea-152069

RESUMO

Face is the forefront of aesthetics. Surgical resection of the maxillae and facial structures for treatment of cancer, trauma, congenital deformities or infection causes maxillofacial defect that has serious impact on the individual’s esthetic and has great psychological trauma of social outcast. When the presented defect is extensive and supporting structures is lacking, the rehabilitation and restoring functions is a challenging task. Rehabilitation becomes even more difficult when the problems at defect site are associated with the complications. An attempt has been made to rehabilitate of a patient at terminal stage having extensive maxillofacial defect with inoperable carcinoma, infections, and restricted mouth opening.

20.
J Biosci ; 2012 Mar; 37 (1): 25-31
Artigo em Inglês | IMSEAR | ID: sea-161636

RESUMO

In this study, Arthrobacter luteolus, isolated from rare earth environment of Chavara (Quilon district, Kerala, India), were found to produce catechol-type siderophores. The bacterial strain accumulated rare earth elements such as samarium and scandium. The siderophores may play a role in the accumulation of rare earth elements. Catecholate siderophore and low-molecular-weight organic acids were found to be present in experiments with Arthrobacter luteolus. The influence of siderophore on the accumulation of rare earth elements by bacteria has been extensively discussed.

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