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1.
J Vasc Res ; 57(4): 213-222, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32294645

RESUMEN

INTRODUCTION: Although both glucose and fructose are hexoses, their catabolism is quite different: the catabolism of fructose is initiated by ketohexokinase and is not regulated by negative feedback, which results in oxidative stress. OBJECTIVE: We hypothesized that fructose impairs endothelium-dependent relaxation via oxidative stress in rat aortic rings. METHODS: Sprague-Dawley rats were offered 20% fructose solution or tap water for 2 weeks, after which vascular reactivity was measured in isolated aortic rings. In a separate experiment, vascular reactivity was measured after acute exposure to ∼10 mM fructose in isolated aortic rings from untreated rats. RESULTS: Although high-fructose intake statistically significantly increased blood pressure and body weight, it did not affect contraction and relaxation in aortic rings. The substitution of fructose for glucose in Krebs solution inhibited vascular relaxation in aortic rings, which was abolished by pretreatment with antioxidants. Decreasing the glucose concentration in Krebs solution inhibited vascular relaxation, whereas decreasing the fructose concentration in Krebs solution improved vascular relaxation in the aortic rings. Pretreatment with antioxidants improved the vascular relaxation in Krebs solution with fructose substituted for glucose. CONCLUSIONS: These results indicate that fructose impairs endothelium-dependent relaxation via oxidative stress in isolated rat aortic rings.


Asunto(s)
Aorta Torácica/efectos de los fármacos , Endotelio Vascular/efectos de los fármacos , Fructosa/toxicidad , Estrés Oxidativo/efectos de los fármacos , Vasodilatación/efectos de los fármacos , Animales , Aorta Torácica/metabolismo , Aorta Torácica/fisiopatología , Presión Sanguínea/efectos de los fármacos , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiopatología , Técnicas In Vitro , Masculino , Ratas Sprague-Dawley , Aumento de Peso/efectos de los fármacos
2.
Microsc Microanal ; 19 Suppl 5: 49-53, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23920173

RESUMEN

We investigated the microstructural evolution of Sn(96.4)Ag(2.8)Cu(0.8) solder through in situ heating transmission electron microscopy observations. As-soldered bump consisted of seven layers, containing the nanoeutectic lamella structure of AuSn and Au5Sn phases, and the polygonal grains of AuSn2 and AuSn4, on Au-plated Cu bond pads. Here, we found that there are two nanoeutectic lamellar layers with lamella spacing of 40 and 250 nm. By in situ heating above 140°C, the nanoeutectic lamella of AuSn and Au5Sn was decomposed with structural degradation by sphering and coarsening processes of the lamellar interface. At the third layer neighboring to the lamella layer, on the other hand, Au5Sn particles with a zig-zag shape in AuSn matrix became spherical and were finally dissipated in order to minimize the interface energy between two phases. In the other layers except both lamella layers, polycrystal grains of AuSn2 and AuSn4 grew by normal grain growth during in situ heating. The high interface energy of nanoeutectic lamella and polygonal nanograins, which are formed by rapid solidification, acted as a principal driving force on the microstructural change during the in situ heating.

3.
Trauma Violence Abuse ; 24(4): 2297-2318, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-35603524

RESUMEN

Aims: Child maltreatment (CM) is a global public health and social problem, resulting in serious long-term health and socioeconomic consequences. As parents are the most common perpetrators of CM, parenting interventions are appropriate strategies to prevent CM. However, research on parenting interventions on CM has been hampered by lack of consensus on what measures are most responsive to detect a reduction in parental maltreating behaviours after parenting intervention. This systematic review aimed to evaluate the responsiveness of all current parent- or caregiver-reported CM measures. Methods: A systematic search was conducted in CINAHL, Embase, ERIC, PsycINFO, PubMed and Sociological Abstracts. The quality of studies and responsiveness of the measures were evaluated using the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines for systematic reviews of patient-reported outcome measures. Only measures developed and published in English were included. Studies reporting data on responsiveness of the included measures were selected. Results: Sixty-nine articles reported on responsiveness of 15 identified measures. The study quality was overall adequate. The responsiveness of the measures was overall insufficient or not reported; high-quality evidence on responsiveness was limited. Conclusions: Only the Physical Abuse subscale of the ISPCAN Child Abuse Screening Tool for use in Trials (ICAST-Trial) can be recommended as most responsive for use in parenting interventions, with high-quality evidence supporting sufficient responsiveness. All other overall scales or subscales of the 15 included measures were identified as promising based on current data on responsiveness. Additional psychometric evidence is required before they can be recommended.


Asunto(s)
Cuidadores , Maltrato a los Niños , Niño , Humanos , Revisiones Sistemáticas como Asunto , Padres , Responsabilidad Parental , Maltrato a los Niños/prevención & control
4.
Food Sci Anim Resour ; 43(1): 113-123, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36789198

RESUMEN

This study investigated the predictability of cooking loss of pork loin through relatively easy and quick measurable quality properties. The pH, color, moisture, protein content, and cooking loss of 100 pork loins were measured. The explanatory variables included in all linear regression models with an adjust-r2 value of ≥0.5 were pH and the protein content. In the linear regression model predicting cooking loss, the highest adjust-r2 value was 0.7, with pH, CIE L*, CIE b*, moisture, and protein content as the explanatory variables. In 30 pork loins, electrical conductivity was additionally measured, and as a result of linear regression analysis for predicting cooking loss, the highest adjust-r2 value was 0.646 with electrical conductivity measured at 40 Hz, with pH and color as the explanatory variables. Ordinal logistic regression analysis was performed to predict the three grades (low, middle, and high) of loin cooking loss using pH, color, and 40 Hz electrical conductivity as the explanatory variables, and the percent concordance was 93.8%. In conclusion, the addition of electrical conductivity as an explanatory variable did not increase the prediction accuracy of the linear regression model for predicting cooking loss; however, it was demonstrated that it is possible to predict and classify the cooking loss grade of pork loin through quality properties that can be measured quickly and easily.

5.
Cancer Med ; 12(22): 21022-21031, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37902239

RESUMEN

BACKGROUND: Rising costs of cancer treatments challenge even areas with universal health coverage. There's a need to assess current medical care utilization trends among patients with cancer to guide public health policy, resource allocation, and set informed healthcare goals. METHODS: We analyzed the latest trends in medical care utilization by cancer patients in four areas-drugs, radiation therapy (RT), surgery, and diagnostic procedures-using clinical databases extracted from electronic medical records of a tertiary hospital in Korea between 2014 and 2019. Compound adjusted growth rates (CAGR) were computed to capture the annual growth over the study period. RESULTS: A total of 74,285 cancer patients were identified, with 40.3% (29,962), 14.2% (10,577), 31.1% (23,066), and 92.6% (68,849) of patients having received at least one anticancer agent, RT, surgery, and diagnostic procedure, respectively, over the period. We observed a 1.7-fold increase in the use of targeted · immune-oncology agents (from 6.8% to 11.6%) and a 21-fold increase (from 3.0% in 2014 to 65.7%) in intensity-modulated RT (IMRT) use over the period. In contrast, we observed a continuous decrease in the proportion of patients who underwent surgical treatment from 12.2% in 2014 to 10.9% in 2019. This decrease was particularly noticeable in patients with colon cancer (from 28.5% to 24.2%) and liver cancer (from 4.1% to 2.9%). CONCLUSION: From 2014 to 2019, there was a significant rise in the use of targeted · immune-oncology agents and IMRT, alongside a decline in surgeries. While targeted · immune-oncology agents and IMRT may offer promising outcomes, their financial impact and potential for overuse necessitate careful oversight and long-term cost-effectiveness studies.


Asunto(s)
Neoplasias , Radioterapia de Intensidad Modulada , Humanos , Centros de Atención Terciaria , Neoplasias/epidemiología , Neoplasias/terapia , Neoplasias/etiología , Radioterapia de Intensidad Modulada/efectos adversos , Oncología Médica/métodos , República de Corea/epidemiología
6.
J Nanosci Nanotechnol ; 12(2): 1466-70, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22629980

RESUMEN

The electrical transport of individual ZnO nanorod devices manufactured by focused ion beam (FIB) was investigated by the direct measurement of electrical resistance at electrode junctions of cross-sectioned devices using two nanoprobes. The cathodoluminescence (CL) measurements were also performed to evaluate the crystallinity at the center and edge of the cross-sectioned ZnO nanorods. The electrical transport of the individual ZnO nanorod device depends strongly on the crystallinity of the ZnO nanorod itself and the carbon contents at Pt junctions. The ZnO-Au junction of the device acted as the fastest path for electrical transport.

7.
J Nanosci Nanotechnol ; 12(2): 1476-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22629982

RESUMEN

AIN/CrN multilayer hard coatings with various bilayer thicknesses were fabricated by a reactive sputtering process. The microstructural and mechanical characterizations of multilayer coatings were investigated through transmission electron microscope (TEM) observations and the hardness measurements by nano indentation. In particular, the variation of chemical bonding states of the bilayer nitrides was elucidated by near edge X-ray absorption fine structure (NEXAFS) spectroscopy. Many broken nitrogen bonds were formed by decreasing the bilayer thickness of AIN/CrN multilayer coatings. Existence of optimum AIN/CrN multilayer coatings thickness for maximum hardness could be explained by the competition of softening by the formation of broken nitrogen bonds and strengthening induced by decreasing bilayer thickness.

8.
J Nanosci Nanotechnol ; 12(2): 1581-4, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22630005

RESUMEN

AlxTi1-xN/CrN multilayer coatings were fabricated by magnetron sputtering and those hardness variations were studied by observing the crack propagation and measuring the chemical bonding state of nitrides by Ti addition. While AlN/CrN multilayer shown stair-like crack propagation, AlxTi1-xN/CrN multilayer illustrated straight crack propagation. Most interestingly, Ti addition induced more broken nitrogen bonds in the nitride multilayers, leading to the reduction of hardness. However, the hardness of Al0.25Ti0.75N/CrN multilayer, having high Ti contents, increased by the formation of many Ti-N bond again instead of Al-N bond. From these results, we found that linear crack propagation behavior was dominated by broken nitrogen bonds in the AlxTi1-xN/CrN multilayer coatings.

9.
Nano Lett ; 11(8): 3499-502, 2011 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-21755954

RESUMEN

We report that defect-free Au nanowires show superplasticity on tensile deformation. Evidences from high-resolution electron microscopes indicated that the plastic deformation proceeds layer-by-layer in an atomically coherent fashion to a long distance. Furthermore, the stress-strain curve provides full interpretation of the deformation. After initial superelastic deformation, the nanowire shows superplastic deformation induced by coherent twin propagation, completely reorientating the crystal from <110> to <100>. Uniquely well-disciplined and long-propagating atomic movements deduced here are ascribed to the superb crystallinity as well as the radial confinement of the Au nanowires.

10.
Korean J Intern Med ; 37(3): 631-638, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35124940

RESUMEN

BACKGROUND/AIMS: Hip fracture and acute exacerbation of chronic obstructive pulmonary disease (AE-COPD) could increase mortality in patients with COPD. There are no data on the relationship between AE-COPD and hip fracture, which may significantly affect the prognosis of patients with COPD. Therefore, we conducted this study to determine the effects of AE-COPD on hip fractures in patients with COPD. METHODS: This retrospective, nested, case-control study included 253,471 patients with COPD (≥ 40 years of age) identified from the Korea National Health Insurance Service-National Health Screening Cohort (NHIS-HEALS) from 2002 to 2015. Among 176,598 patients with COPD, 1,415 patients with hip fractures were identified. Each case was matched to one control for age (within 10 years), sex, and year of COPD diagnosis. We estimated the adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for hip fractures associated with AE-COPD using conditional logistic regression analysis, adjusting for underlying diseases and smoking history. RESULTS: In patients with AE-COPD, the risk of hip fracture was 2.50 times higher, regardless of systemic corticosteroid use and underlying disease (aOR, 2.50; 95% CI, 1.67 to 3.75). The risk of hip fracture increased if there was one episode of AE in the year before hip fractures (aOR, 2.25; 95% CI, 1.66 to 3.05). Moreover, the risk of hip fracture also increased in patients with more than two episodes of AE the year before hip fractures (aOR, 2.57; 95% CI, 1.61 to 4.10). CONCLUSION: AE-COPD increases the risk of hip fracture regardless of underlying diseases, including osteoporosis, and treatment with systemic corticosteroids.


Asunto(s)
Fracturas de Cadera , Enfermedad Pulmonar Obstructiva Crónica , Estudios de Casos y Controles , Niño , Fracturas de Cadera/diagnóstico , Fracturas de Cadera/epidemiología , Fracturas de Cadera/etiología , Humanos , Programas Nacionales de Salud , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Estudios Retrospectivos , Factores de Riesgo
11.
Rev Sci Instrum ; 93(9): 093703, 2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36182474

RESUMEN

Recent advances in improving the spectroscopic energy resolution in scanning tunneling microscopy (STM) have been achieved by integrating electron spin resonance (ESR) with STM. Here, we demonstrate the design and performance of a homebuilt STM capable of ESR at temperatures ranging from 1 to 10 K. The STM is incorporated with a homebuilt Joule-Thomson refrigerator and a two-axis vector magnet. Our STM design allows for the deposition of atoms and molecules directly into the cold STM, eliminating the need to extract the sample for deposition. In addition, we adopt two methods to apply radio-frequency (RF) voltages to the tunnel junction: the early design of wiring to the STM tip directly and a more recent idea to use an RF antenna. Direct comparisons of ESR results measured using the two methods and simulations of electric field distribution around the tunnel junction show that, despite their different designs and capacitive coupling to the tunnel junction, there is no discernible difference in the driving and detection of ESR. Furthermore, at a magnetic field of ∼1.6 T, we observe ESR signals (near 40 GHz) sustained up to 10 K, which is the highest temperature for ESR-STM measurement reported to date, to the best of our knowledge. Although the ESR intensity exponentially decreases with increasing temperature, our ESR-STM system with low noise at the tunnel junction allows us to measure weak ESR signals with intensities of a few fA. Our new design of an ESR-STM system, which is operational in a large frequency and temperature range, can broaden the use of ESR spectroscopy in STM and enable the simple modification of existing STM systems, which will hopefully accelerate a generalized use of ESR-STM.

12.
Trauma Violence Abuse ; 22(5): 1013-1031, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-31928172

RESUMEN

AIMS: Child maltreatment (CM) is a serious public health issue, affecting over half of all children globally. Although most CM is perpetrated by parents or caregivers and their reports of CM is more accurate than professionals or children, parent or caregiver report instruments measuring CM have never been systematically evaluated for their content validity, the most important psychometric property. This systematic review aimed to evaluate the content validity of all current parent or caregiver report CM instruments. METHODS: A systematic literature search was performed in CINAHL, Embase, ERIC, PsycINFO, PubMed, and Sociological Abstracts; gray literature was retrieved through reference checking. Eligible studies needed to report on content validity of instruments measuring CM perpetrated and reported by parents or caregivers. The quality of studies and content validity of the instruments were evaluated using the COnsensus-based Standards for the selection of health Measurement INstruments guidelines. RESULTS: Fifteen studies reported on the content validity of 15 identified instruments. The study quality was generally poor. The content validity of the instruments was overall sufficient, but most instruments did not provide high-quality evidence for content validity. CONCLUSIONS: Most instruments included in this review showed promising content validity. The International Society for the Prevention of Child Abuse and Neglect Child Abuse Screening Tool for use in Trial appears to be the most promising, followed by the Family Maltreatment-Child Abuse criteria. However, firm conclusions cannot be drawn due to the low quality of evidence for content validity. Further studies are required to evaluate the remaining psychometric properties for recommending parent or caregiver report CM instruments.


Asunto(s)
Cuidadores , Maltrato a los Niños , Niño , Humanos , Padres , Psicometría , Reproducibilidad de los Resultados
13.
Trauma Violence Abuse ; 22(5): 1296-1315, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-32270753

RESUMEN

AIMS: Child maltreatment (CM) is global public health issue with devastating lifelong consequences. Global organizations have endeavored to eliminate CM; however, there is lack of consensus on what instruments are most suitable for the investigation and prevention of CM. This systematic review aimed to appraise the psychometric properties (other than content validity) of all current parent- or caregiver-reported CM instruments and recommend the most suitable for use. METHOD: A systematic search of the CINAHL, Embase, ERIC, PsycINFO, PubMed, and Sociological Abstracts databases was performed. The evaluation of psychometric properties was conducted according to the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines for systematic reviews of patient-report outcome measures. Responsiveness was beyond the scope of this systematic review, and content validity has been reported on in a companion paper (Part 1). Only instruments developed and published in English were included. RESULTS: Twenty-five studies reported on selected psychometric properties of 15 identified instruments. The methodological quality of the studies was overall adequate. The psychometric properties of the instruments were generally indeterminate or not reported due to incomplete or missing psychometric data; high-quality evidence on the psychometric properties was limited. CONCLUSIONS: No instruments could be recommended as most suitable for use in clinic and research. Nine instruments were identified as promising based on current psychometric data but would need further psychometric evidence for them to be recommended.


Asunto(s)
Cuidadores , Comparación Transcultural , Niño , Humanos , Padres , Psicometría , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
14.
Environ Pollut ; 267: 115466, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32882462

RESUMEN

The present study was aimed at investigating the effects of different acids and pH neutralizers applied to dredged marine sediment for the treatment of heavy metals, and the resulting influence on the sediment quality as a plant growth medium. The inspection of barley germination in the dredged marine sediment revealed that residual salts are critical plant stressors whose adverse effects exceed those exhibited by high-level heavy metals and petroleum hydrocarbons present in the sediment. Acid washing and pH neutralization reduced not only the heavy metal contents but also the sediment salinity (by factors of 6.1-9.5), resulting in 100% germination of barley. For acid-washed and calcium-oxide-neutralized sediment, the barley growth was comparable to that observed in untreated and water washed sediment despite factors of 5.2-8.0 greater sediment salinity in the former. This result represents the protective effect of residual calcium against sodium and chloride toxicity. Water washing of acid-washed and pH-neutralized sediments further enhanced barley growth owing to the reduction in osmotic pressure. This study showed the effect of different sediment-washing reagents on the product quality. It also indicated the significance of balancing the enhancement of product quality and economic cost of further treatment requirements.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Fertilidad , Sedimentos Geológicos , Concentración de Iones de Hidrógeno , Metales Pesados/análisis , Suelo
15.
Environ Sci Pollut Res Int ; 27(15): 18911-18923, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32207005

RESUMEN

A cost-effective, easy-to-implement, and sustainable approach is needed to mitigate the production of alkaline leachate from steel slags that are reused or disposed in the environment. To address this issue, a humidification treatment process, which is operated by wetting a stack of steel slag using aqueous reagents and letting atmospheric CO2 to be passively diffused into the slag pores to induce slag carbonation reaction, was previously developed. In this study, we demonstrate that the leachate of raw steel slag can be recycled and used as a humidification reagent to substantially enhance the treatment efficiency as well as to enable operating the process with neither synthetic chemical consumption nor wastewater discharge. In a 24-h study, a 0.61-unit reduction in slag pH is achieved using a raw slag leachate as a reagent, which is substantially greater than a 0.28-unit reduction using deionized water. The net amount of CaCO3 produced during an extended humidification duration of 4 weeks is increased by 2.7-fold when the leachate is used instead of deionized water. A series of systematically designed experiments demonstrates that the pH (11.0) and ionic strength (0.0048) are the two major characteristics of the raw slag leachate that contribute to the enhanced efficiency of humidification treatment. With further demonstration at larger scales in follow-up studies, the novel humidification process that utilizes the leachate generated on-site as a reagent is expected to be a feasible alternative for alkali waste treatment prior to its reuse or disposal.


Asunto(s)
Residuos Industriales/análisis , Acero , Dióxido de Carbono , Carbonatos , Concentración de Iones de Hidrógeno
16.
Dis Model Mech ; 13(5)2020 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-32179549

RESUMEN

High-salt intake and high-fructose intake are risk factors for hypertension via oxidative stress and inflammation. T helper (Th)17 lymphocytes play an important role in the development of hypertension. Here, we tested the hypothesis that activation of pathogenic Th17 lymphocytes induces hypertension after high-fructose intake in Dahl salt-sensitive (SS) but not Dahl salt-resistant (SR) rats. Eight-week-old male SS and SR rats were offered 20% fructose solution or tap water only for 4 weeks. Systolic blood pressure was measured by the tail-cuff method. T lymphocyte [Th17 and T regulatory (Treg)] profiling was determined via flow cytometry. The expression of Th17-related (IL-17A, IL-17RA, IL-23R and RORγt) and Treg-related (IL-10, CD25, FOXP3 and TGFß) factors were measured via ELISA or qRT-PCR. Th17 lymphocytes isolated from high-fructose-fed SS rats were intraperitoneally injected into recipient SS and SR rats, and recombinant IL-23 protein was subcutaneously injected into SS and SR rats to induce hypertension.High-fructose intake induced hypertension via the activation of pathogenic Th17 lymphocytes in SS but not SR rats. Injection of activated Th17 lymphocytes isolated from fructose-fed SS rats induced hypertension via increase of serum IL-17A only in recipient SS rats. In addition, injection of IL-23 induced hypertension via activation of pathogenic Th17 lymphocytes only in SS rats.Thus, activation of pathogenic Th17 lymphocytes induces hypertension after high-fructose intake in SS but not SR rats. These results indicate that immunologic tolerance plays an important role in protection against hypertension in SR rats.


Asunto(s)
Hipertensión/inmunología , Activación de Linfocitos/inmunología , Células Th17/inmunología , Animales , Presión Sanguínea , Peso Corporal , Citocinas/sangre , Citocinas/metabolismo , Factores de Transcripción Forkhead/metabolismo , Fructosa , Intolerancia a la Glucosa/sangre , Intolerancia a la Glucosa/complicaciones , Intolerancia a la Glucosa/inmunología , Hipertensión/sangre , Hipertensión/complicaciones , Proteínas Inmediatas-Precoces/metabolismo , Interleucina-23/metabolismo , Masculino , Modelos Biológicos , Fosforilación , Proteínas Serina-Treonina Quinasas/metabolismo , Ratas Endogámicas Dahl , Transducción de Señal , Sístole , Linfocitos T Reguladores/inmunología
17.
Rev Sci Instrum ; 91(2): 023314, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-32113426

RESUMEN

We report the design, construction, and operation results of an 18 T 70 mm cold-bore high temperature superconductor (HTS) no-insulation (NI) magnet, which is developed for an axion haloscope experiment. The magnet consists of 44 double-pancake coils wound with multi-width and multi-thickness REBa2Cu3O7-x (RE = rare earth) tapes. Owing to the NI feature, the magnet is highly compact; is 162 mm in outer diameter and 476 mm tall; and provides an environment of 0.22 T2 m3 within the cold-bore target space of 66 mm in diameter and 200 mm in length. After an initial performance test at SuNAM Co. Ltd., the magnet was installed at the Center for Axion and Precision Physics Research (CAPP) of the Institute for Basic Science in Daejeon, South Korea, in August 2017. The magnet has been successfully operating at the CAPP since then, except for maintenance in October 2018. The magnet may represent the first high field HTS user magnet that experienced long-term operation of over one year.

18.
Sci Total Environ ; 671: 598-607, 2019 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-30933816

RESUMEN

A slag humidification process that aims to reduce the leachate pH of steel slag via carbonation was accomplished by simply wetting the slag and exposing it to the atmosphere for passive diffusion of atmospheric CO2. The optimization parameters of the process were studied. Results showed that by wetting the slag using various aqueous solutions (deionized water, NaCl solution and NaOH solution), such that its moisture content nearly reaches its water holding capacity, a significant reduction in leachate pH could be achieved. Pretreatment of the slag using 1 M NaOH and subsequent humidification using deionized water showed the best efficiency of 1.1 pH unit reduction among the tested conditions. Slag pretreatment could substantially enhance the carbonation degree on the slag surface, leading to conservation of the treatment effectiveness up to three times the leachate replenishment using deionized water. The benefit of the alkaline treatment to promote slag carbonation could also be achieved using a low to moderate (0.005-0.1 M) NaOH solutions for humidification without the pretreatment step. A 72.5% increase in the treatment efficiency could be achieved via a humidification treatment using 0.005 M NaOH solution compared to that using deionized water. This study shows the promise of humidification treatment as a low-cost, easily implemented, and environmentally friendly slag pH neutralization process that can be applied in the field for slag treatment prior to its use or disposal in the environment.

19.
Sci Total Environ ; 639: 1432-1439, 2018 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-29929306

RESUMEN

This study investigates the effect of anionic surfactant modification on activated carbon (AC) to enhance the adsorption of ammonium ion in aqueous solution. Sodium dodecyl sulfate (SDS), sodium dodecyl benzene sulfonate (SDBS) or sodium octanoate (SO) was used for the modification. At the initial aqueous concentration of 55 mg NH4-N/L and the adsorbent dose of 50 g/L, the SDS-modified AC showed the highest ammonium removal efficiency of 82% among the modified ACs studied. The hydrophobic group of SDS was strongly attached to AC showing almost negligible desorption after the modification. At the same time, the sulfate functional group of SDS provided ion exchange sites favorable for the ammonium ion adsorption. By maximizing SDS loading to the AC, ammonium removal efficiency can further be improved (5% increase). When Na+, K+ or Ca2+ coexisted in the ammonium solution at the concentration of 55 mg/L, the inhibition effect of these cations on ammonium removal efficiency was negligible (<5%). This study shows the potential of anionic surfactant-modified ACs as the excellent adsorbents for ammonium removal from water.

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