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Mn-N-C materials have received increasing interest in recent years because of their low Fenton reactivity and ORR activity comparable to those of their Fe-N-C and Co-N-C counterparts. In this contribution, an atomically dispersed Mn-N-C electrocatalyst with a prominent oxygen reduction performance was constructed by employing a cationic Cd-MOF as a precursor that can facilely and accurately introduce MnO4- anions through anion exchange. The best-performing Mn-N-C catalyst displays a 0.96 V (vs RHE) Eonset (onset potential) and a 0.87 V (vs RHE) E1/2 (half-wave potential) in an alkaline solution, which exceed those of the benchmark Pt/C catalyst. In particular, the maximal power density of the self-made zinc-air battery reaches 200 mW·cm-2, surpassing that of most reported Mn-N-C materials.
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Methyl formate (MF) is one of the most important chemical commodities, which has a wide range of applications. Due to environmental friendliness, mild reaction conditions, and easy operations, electrosynthesis of MF has garnered increasing attention in recent years. In this work, we reported an electrosynthesis route toward MF in a halide-containing methanol solution. The thorough mechanistic investigations point out that electrosynthesis of MF is accomplished by instant reaction between aldehyde from anodic methanol oxidation, and methoxy bromide (CH3OBr) that is in-situ generated by reaction of Br2 from anodic oxidation of Br- with methoxide (CH3O-) from cathodic reduction of methanol. This method features high atomic economy only producing valuable MF and hydrogen gas, and shows distinct advantages compared to the reported MF electrosynthesis methods. Even at 200â mA/cm2, the faradaic efficiency (FE) of MF remains consistently around 60 % at the anode while a 100 % FE hydrogen gas is produced at the cathode.
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The electrochemical reduction of carbon dioxide into energy-carrying compounds or value-added chemicals is of great significance for diminishing the greenhouse effect. However, it is still imperative to replace the less-value anodic oxygen evolution reaction (OER) to improve the technical economy. Herein, we firstly reported a bifunctional CuS/TiO2 catalyst for both anodic methanol oxidation reaction (MOR) and cathodic carbon dioxide reduction (CO2R). The in-built abundant CuS/TiO2 heterointerfaces are found to boost the CO2R and MOR to produce formate. Based on the unique bifunctionality of CuS/TiO2, a paired electrosynthesis of formate was performed with a total Faradaic efficiency (FE) of about 170 %, in which the cathodic CO2R achieved a formate FE of about 70 %, and the anodic MOR exhibited an almost 100 % formate FE.
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A highly efficient metal-free N-doped carbon electrocatalyst toward oxygen reduction was obtained by one-pot pyrolysis of a single Zn(II)-MOF with mixed azolate and terephthalate ligands, demonstrating E1/2 of 0.88 V (vs. RHE) in 0.1 M KOH, and 0.79 V (vs. RHE) in 0.5 M H2SO4. It represents one of the best metal-free N-doped carbon electrocatalysts for the acidic ORR.
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Reasonable application of microbial agents can significantly improve soil environment and increase the yield and quality of vegetables. In this study, we examined the effects of different forms of microbial agents on the growth and quality of Brassica rapa L. ssp. chinensis Makino (non-heading Chinese cabbage) under the conditions of no microbial agent application, liquid and solid microbe agents application. The results showed that compared with no microbial agent, application of liquid and solid microbial agent significantly improved soil urease activity, plant nitrogen content, leaf area, SPAD value, and net photosynthetic rate, and increased vegetable production by 26.9% and 34.4% respectively. Meanwhile, the total phenol content and ascorbic acid content of non-heading Chinese cabbage were increased and nitrate content was significantly decreased by applying microbial agents. Thus, rational application of microbial agents promoted the yield and quality of non-heading Chinese cabbage. From the perspective of vegetable growth, liquid microbial agents work fast, solid microbial agents had good long-term efficacy. The cooperating application with organic and inorganic fertilizers would facilitate the excellent quality and high yield of vegetables.
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Brassica rapa , Brassica , Ácido Ascórbico , China , Hojas de la PlantaRESUMEN
OBJECTIVE: To assess the effectiveness of complementary food supplements with protein and multi-micronutrients on hemoglobin and anemia in infants and young children. METHODS: In 5 poor counties of Gansu, 984 children aged 6-12 months were enrolled and divided into two groups. In addition to the usual home-made complementary food, all the children were fed one sachet of either Formula I or Formula II supplements each day. Protein and micronutrients were provided in Formula I, while the same energy intake was secured in Formula II as in Formula I. A massive dose of vitamin A was supplemented to all the children every 6 months. Hemoglobin test was done at the same time. RESULTS: Prevalence of anemia was about 35% in both Formula I and Formula II group at baseline, and there were no differences in hemoglobin concentration between the two groups. During the 6-month and 12-month supplementation, hemoglobin of children in Formula I group was higher than that in Formula II group (P < 0.05), and hemoglobin increase in Formula I group was significantly higher than that in Formula II group (P < 0.001). After 6- and 12-month supplementation, the prevalence of anemia in Formula I group dropped to 19.1% and 8.2% respectively, and it was 28.0% and 12.4% in Formula 2 group. The prevalence of anemia in Formula I group was significantly lower than that in Formula II group (P < 0.05). After adjusting age and hemoglobin level at baseline, the hemoglobin increase at age of 24 months in formula 1 group was higher (10.7 g/L vs 7.9 g/L, P < 0.0001). CONCLUSION: Micronutrient fortified complementary food supplements, with large-dose vitamin A, is effective for children aged 6-12 months in terms of iron deficiency prevention.
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Anemia Ferropénica/prevención & control , Suplementos Dietéticos , Alimentos Fortificados/análisis , Alimentos Infantiles/análisis , Hierro de la Dieta/administración & dosificación , Hierro de la Dieta/farmacología , Anemia Ferropénica/sangre , China , Hemoglobinas/metabolismo , Humanos , Lactante , Pobreza , Población RuralRESUMEN
OBJECTIVE: To investigate the effects of complementary food supplements with protein and multimicronutrients on growth of infants and yound children in poor rural area in Gansu Province, China. METHODS: In 5 poor counties of Gansu Province, 1478 children aged 4-12 months were enrolled and divided into two groups. In addition to the usual home-made complementary food, all the children were fed one sachet of either formula I or formula II per day, protein and micronutrient were supplemepted in formula I group, fomula II group got energy supplement corresponding with same energy intake as formula I, a massive dose of vitamin A was supplemented to both groups every 6 months interval. Weight and height measurements were done every 3 months until they were 24 months old. RESULTS: At baseline survey, LAZ and WAZ of children in formula II group was better than those of formula I group, the prevalence of under nutrition in formula I was higher than those in formula II group, but not statistically significant. After 12 months supplementation, the differences of LAZ and WAZ between the two groups diminished, the stunting prevalence of the two groups was close, it demonstrated that formula I was slightly more effective than formula II, the effect size was 0.17. Formula I has positive effect independently with the nutrition status of children. When all children were 24 months, formula I was better than formula II in LAZ and WAZ changes P < 0.05), the length changes were bigger in formula I group (P < 0.05). If takeing the children initiating supplementation at under age of 7 month, LAZ changes in formula I group and formula II group was statistically significant (P < 0.005). The average length increased in formula I group was 1.3cm longer. CONCLUSION: Multinutrient-fortified complementary food supplement could be effective for children aged 4-12 month in terms of growth promotion. The study proved that application of home-level fortification of supplementation into the regular complementary feeding in poor rural China may be feasible.
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Desarrollo Infantil , Suplementos Dietéticos , Alimentos Fortificados/análisis , Micronutrientes/administración & dosificación , Estatura , Peso Corporal , Preescolar , China , Proteínas en la Dieta/administración & dosificación , Femenino , Humanos , Lactante , Alimentos Infantiles/análisis , Masculino , Pobreza , Población Rural , Vitamina A/administración & dosificaciónRESUMEN
OBJECTIVE: To investigate the effects of complementary food supplements on development of infants and young children in poor rural. METHODS In 5 poor counties of Gansu Province, children aged 4 - 12 months were enrolled and divided into two groups. In addition to the usual home-made complementary food, all the children were fed one package of either formula I or formula UI per day, protein and micronutrient were supplemented in formula I group. Formula II provided the same energy as formula I . Both groups were supplemented with vitamin A, weight and height measurements have been done every 3 months, and hemoglobin tests were done every 6 month. Development quotient was measured when they were aged 24 month. RESULTS: Development quotient of 475 children were tested. The difference of Development quotient between the two groups is statistically significant ( P < 0.05), gross motor development also is different (P < 0.05), there are no difference in time of supplements, nutrition status, sex ratio, mother' s education between two group, but hemoglobin and anemia prevalence of children in formula I group is significant lower than Formula II group. CONCLUSION: Micronutrient fortified complementary food supplement is effective for children aged 4 - 12 month in terms of mental development.
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Desarrollo Infantil , Suplementos Dietéticos , Inteligencia , Vitamina A/administración & dosificación , China , Femenino , Humanos , Lactante , Masculino , Pobreza , Población RuralRESUMEN
OBJECTIVE: To describe the costs of medical care and utilization of health service of patients with HIV/AIDS. METHODS: Patients with human immunodeficiency virus (HIV)/AIDS treated in the Beijing You'an Hospital were interviewed retrospectively during December 1999. Data on demographic characteristics, disease process, and utilization of health service and costs of hospital-based medical care were collected. RESULTS: A total number of 29 patients with HIV/AIDS were interviewed, including 17 (58.62%) asymptomatic HIV infections and 12 AIDS patients. Asymptomatic HIV infections had a mean of 6 outpatient visits, 1.3 hospitalizations and 58.6 inpatient hospital days per person-year. AIDS patients made, on average, 7.8 outpatient visits, 2.1 hospitalizations and 200.2 inpatient hospital days per person-year. The outpatient and inpatient medical costs were 13,729 RMB and 4,745 RMB for asymptomatic HIV infections, and 15,053 RMB and 22,242 RMB for AIDS patients per person-year respectively. For those who took both outpatient and inpatient medical care, the medical care costs, including costs of outpatient care and those of inpatient care, were 16,248 RMB for asymptomatic HIV infections and 36,795 RMB for AIDS patients. CONCLUSION: Demands for health services and costs for medical care were high among patients with HIV/AIDS. Further study on utilization of health services and cost of medical care for patient with HIV/AIDS in a wider geographic coverage are needed.
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Síndrome de Inmunodeficiencia Adquirida/economía , Infecciones por VIH/economía , VIH-1 , Costos de la Atención en Salud , Servicios de Salud/estadística & datos numéricos , Adolescente , Adulto , Niño , China , Femenino , Servicios de Salud/economía , Precios de Hospital , Hospitalización/economía , Humanos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
OBJECTIVE: To identify the relationship of body mass index (BMI) and blood pressure in 7 - 15 years children and adolescents of Beijing so as to provide scientific basis for early prevention of hypertension and to provide evidence for verification on the category criterion of overweight and obesity in children and adolescents of China, recommended by the Working Group on Obesity in China (WGOC) to sensitively distinguish the blood pressure in normal weight, overweight and obesity populations. METHODS: A cross-sectional survey on epidemiological characteristics of obesity with stratified cluster sampling method carried out in Beijing in April and May, 2000. 5155 students aged 6 - 15 years were selecte das research subjects. The category criterion of overweight and obesity in children and adolescents of China was recommended by WGOC, the diagnostic criterion of hypertension in children was recommended by CDC in the USA. Statistics analysis system (SAS 8.1) including partial person correlation analysis, t-test, chi(2) test and logistic multi-factors regression analysis was used to analyses the data from 4982 subjects aged 7 - 15 years. RESULTS: (1) after the age and gender were adjusted, the BMI positive correlation with systolic blood pressure (SBP) and diastolic blood pressure (DBP) was found independent in 7 - 15 years children and adolescents (P < 0.0001) and the partial relation coefficients(r) between BMI and SBP and DBP were 0.323 87 and 0.245 88 respectively. (2) the means of SBP and DBP in obesity group were significantly higher then overweight, while overweight was significantly higher then normal weight group (P < 0.0001). (3) the prevalence rates of hyper-SBP, hyper-DBP and hypertension were significantly different (P < 0.0001). When compared with the normal weight group, the relation risk (RR) for hypertension in overweight group and obesity group were 2.96 and 4.85 respectively. The prevalence rates of hypertension in overweight and obesity group were 19.70% and 24.22% respectively. (4) the results of logistic multi-factors regression analysis showed that both age and weight were effecting on hyper-SBP, hyper-DBP and hypertension (P < 0.0001). After age was adjusted, the RR for hypertension was 2.62, and their confidence interval (CI) was 2.36 - 2.91 in obesity or overweight, between overweight and normal weight. CONCLUSION: (1) the BMI positive correlation with SBP and DBP was found independent in 7 - 15 years children and adolescents of Beijing, and the risk for hypertension maybe increased when these people with overweight and obesity, it is very important for hypertension prevention and control that overweight and obesity prevention and control in children and adolescents. (2) the sensitivity of the category criterion of overweight and obesity in children and adolescents of China, recommended by WGOC have been verified on distinguish the blood pressure in normal weight, overweight and obesity populations.