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1.
Zhonghua Nan Ke Xue ; 29(9): 821-825, 2023 Sep.
Artículo en Zh | MEDLINE | ID: mdl-38639595

RESUMEN

OBJECTIVE: Exploring the clinical efficacy, safety, and surgical techniques of two-way rendezvous and trenching method for transurethral holmium laser prostatectomy in the treatment of benign prostatic hyperplasia. METHODS: Retrospective analysis of clinical data on preoperative, intraoperative, and postoperative follow-up of 326 patients with benign prostatic hyperplasia who underwent two-way rendezvous and trenching method of transurethral holmium laser prostatectomy at the Urology Department of Wujin People's Hospital in Changzhou City from January 2020 to January 2023. RESULTS: Compared with preoperative measures, IPSS symptom score, quality of life (QoL) score, maximum urinary flow rate (Qmax), and residual urine volume (PVR) were significantly improved at 1, 6, and 12 months postoperatively (P<0.05). Thirty two patients with normal and regular sexual life pre-operation were observed. There were no significant changes in their IIEF-5 score and Erectile Hardness Scale (EHGS) score after surgery compared with pre-operation (P<0.05). There were 9 patients (28.12%) with retrograde ejaculation after surgery. CONCLUSION: The two-way rendezvous and trenching method of transurethral holmium laser prostatectomy is a safe and effective method for treating benign prostatic hyperplasia, with precise results, high safety, minimal trauma, and fast postoperative recovery.


Asunto(s)
Terapia por Láser , Láseres de Estado Sólido , Hiperplasia Prostática , Resección Transuretral de la Próstata , Masculino , Humanos , Próstata , Hiperplasia Prostática/diagnóstico , Calidad de Vida , Láseres de Estado Sólido/uso terapéutico , Estudios Retrospectivos , Resección Transuretral de la Próstata/métodos , Resultado del Tratamiento , Terapia por Láser/métodos , Holmio
2.
Zhonghua Nan Ke Xue ; 29(10): 899-903, 2023 Oct.
Artículo en Zh | MEDLINE | ID: mdl-38639659

RESUMEN

OBJECTIVE: Comparison of clinical efficacy between transurethral holmium laser prostate enucleation (two-way rendezvous and trenching method) and transurethral plasma enucleation. METHODS: A total of 483 patients with benign prostatic hyperplasia who were admitted to our hospital from December 2019 to December 2022 were randomly divided into an observation group (245 cases) and a control group (238 cases) using a random number table method. The observation group underwent transurethral holmium laser prostatectomy, while the control group underwent transurethral plasma prostatectomy,evaluate the efficacy of two surgical methods. RESULT: The IPSS symptom score, quality of life (QOL) score, maximum urinary flow rate (Qmax), residual urine volume (PVR) and other indicators were significantly improved in both groups after 6 months of surgery compared to before (P<0.05), and there was no statistically significant difference between the two groups (P>0.05). The incidence of postoperative complications in the observation group was significantly lower than that in the control group (P<0.05). There was no statistically significant difference in sexual function and retrograde ejaculation between the two groups of patients(P>0.05). CONCLUSION: Both surgical methods have good surgical efficacy, but compared with prostate plasma resection, holmium laser prostatectomy can reduce intraoperative bleeding in patients with BPH, effectively shorten catheter retention time, patient hospitalization time, and postoperative bladder flushing time, resulting in higher quality of life and safety.


Asunto(s)
Terapia por Láser , Láseres de Estado Sólido , Hiperplasia Prostática , Resección Transuretral de la Próstata , Masculino , Humanos , Hiperplasia Prostática/complicaciones , Calidad de Vida , Láseres de Estado Sólido/uso terapéutico , Resección Transuretral de la Próstata/métodos , Próstata/cirugía , Terapia por Láser/métodos , Resultado del Tratamiento , Holmio
3.
Environ Res ; 167: 175-183, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30029039

RESUMEN

BACKGROUND: Both physical exercise and the built environment are associated with cardiovascular diseases (CVDs). Yet, the influence of the multiple dimensions of the built environment and different types of physical exercise on CVDs is not well understood. Further, little is known about the joint effects of physical exercise and the built environment, nor whether one mediates the effect of the other on the risk of CVDs. We aim to investigate the risk of CVDs on middle aged and older Chinese adult populations by analyzing the independent effects, as well as potential interactions and mediation effects of different types of physical exercise and two dimensions of the built environment; namely, greenness and walkability. METHODS: Data were collected from a community-based cross-sectional study (n = 1944). The study participants, aged 40 years or older, came from 32 communities across urban, suburban, and rural areas in Longzihu district of Bengbu, a typical second-tier city in eastern China. Physical exercise data were obtained from the International Physical Activity Questionnaire (IPAQ) question survey. We used a satellite-based Normalized Difference Vegetation Index (NDVI) score to assess greenness exposure. We used both the Walk Score index and the Neighborhood Environment Walkability Scale (NEWS) to assess walkability. Multilevel logistic regression, also known as mixed-effects logistic regression, was used to estimate the associations between physical exercise and the built environment (greenness and walkability) on CVD outcomes while accounting for within-community and within-subdistrict correlations. We followed Baron and Kenny's framework and used bootstrapping to quantify the mediation of physical exercise between built environment and CVD outcomes. Stratified analysis was conducted by age (middle aged and older adults) and gender. RESULTS: Compared to the reference group with little to low physical activities, we found a significantly reduced risk of hypertension (about 20-45% reduction) and coronary heart disease (about 35-55% reduction) among those with moderate to high activities in walking/square dancing or morning exercising/Tai Chi, and a significantly reduced risk of stroke (about 25% reduction) among those with moderate to high activities in walking/square dancing. Compared to the reference group with low NDVI-based greenness exposure, we found a significant reduction in risk of hypertension (about 55-85% reduction), coronary heart disease (about 75% reduction) and stroke (about 45% reduction) among those with moderate to high levels of exposure. Compared to the reference groups with low walkability, we observed about 30-60% lower risk of hypertension and coronary heart disease associated with moderate to high levels of Walk score, and about 20-30% lower risk of hypertension and stroke associated with moderate to high levels of NEWS-based walkability. We found no interactions between physical exercise and the built environment. The associations of greenness and walkability with CVDs were partially explained by physical exercise (up to 55% of the total effect). CONCLUSIONS: Both physical exercise and built environment factors were associated with the risk of CVDs. Our observed association between CVDs and neighborhood greenness exposure and walkability was explained, in part, by physical exercises. Such a role, if confirmed in future studies, could have important implications for policies and programs aimed at increasing green spaces and improving walkability in both urban and rural settings as strategies to promote physical exercise in middle aged and older population.


Asunto(s)
Entorno Construido , Enfermedades Cardiovasculares , Ejercicio Físico , Parques Recreativos , Características de la Residencia , Caminata , Adulto , Anciano , Anciano de 80 o más Años , Entorno Construido/estadística & datos numéricos , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , China , Ciudades , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Parques Recreativos/estadística & datos numéricos , Características de la Residencia/estadística & datos numéricos , Caminata/estadística & datos numéricos
4.
Opt Express ; 25(4): 3122-3132, 2017 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-28241528

RESUMEN

Inspired by crystalline lenses in human eyes, liquid lenses have a simple yet elegant working principle, and result in compact optical systems. Recent numerical studies showed that membranes with variable thicknesses could affect the lens profile. However, fabrication and assembly of a liquid lens with an inhomogeneous membrane is difficult. There is also a lack of experimental studies about the changes of a lens profile during deformation. In this paper, we provided a new experimental approach for characterizing the performance of a liquid lens with an inhomogeneous membrane. A 2D axisymmetric lens model was built in finite element analysis software to theoretically study the non-linear deformation behavior of the inhomogeneous membrane. Then we provided a new approach to fabricate inhomogeneous membranes using a pre-machined aluminum mold. An optical coherence tomography (OCT) system was used to dynamically measure the changes of a lens profile without contact. Both simulation and the experiments indicated that the variation of the thickness of the membrane could affect the lens profile in a predictable manner. A negative conic constant was achieved when a plano-concave membrane was adopted in a liquid lens. Larger increments of the thickness of the membrane in the radial direction resulted in a larger contribution of a conic constant to the lens profile. The presented study offers guidance for image-quality analysis and optimization of a liquid-lens-based optical system.

5.
Biomacromolecules ; 14(5): 1278-86, 2013 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-23495918

RESUMEN

Creating patterns of biomolecules and cells has been applied widely in many fields associated with the life sciences, including diagnostics. In these applications it has become increasingly apparent that the spatiotemporal arrangement of biological molecules in vitro is important for the investigation of the cellular functions found in vivo. However, the cell patterning techniques often used are limited to creating 2D functional surfaces on glass and silicon. In addition, in general, these procedures are not easy to implement in conventional biological laboratories. Here, we show the formation of a living poly(ethylene glycol) (PEG) layer that can be patterned with visible light on plastic surfaces. This new and simple method can be expanded to pattern multiple types of biomolecule on either a previously formed PEG layer or a plastic substrate. Using common plastic wares (i.e., polyethylene films and polystyrene cell culture Petri-dishes), we demonstrate that these PEG-modified surfaces have a high resistance to protein adsorption and cell adhesion, while at the same time, being capable of undergoing further molecular grafting with bioactive motifs. With a photomask and a fluid delivery system, we illustrate a flexible way to immobilize biological functions with a high degree of 2D and 3D spatial control. We anticipate that our method can be easily implemented in a typical life science laboratory (without the need for specialized lithography equipment) offering the prospect of imparting desirable properties to plastic products, for example, the creation of functional microenvironments in biological studies or reducing biological adhesion to surfaces.


Asunto(s)
Materiales Biocompatibles Revestidos/síntesis química , Polietilenglicoles/química , Polietileno/química , Poliestirenos/química , Adhesión Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos/farmacología , Humanos , Luz , Plásticos/química , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie
6.
Clinics (Sao Paulo) ; 77: 100083, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35932505

RESUMEN

OBJECTIVES: Due to Pulmonary Artery Endothelial Cell (PAEC) dysfunction, Pulmonary Hypertension (PH) persists even after the Pulmonary Embolism (PE) has been relieved. However, the mechanism behind this remains unclear. METHOD: Here, the authors incubated Human PAECs (HPAECs) with thrombin to simulate the process of arterial thrombosis. RESULTS: CCK8 results showed a decrease in the viability of HPAECs after thrombin incubation. In addition, the expression of Tissue Factor (TF), Monocyte Chemoattractant Protein 1 (MCP-1), VCAM-1, ICAM-1, cleaved caspase 3, cleaved caspase 9, and Bax protein were all increased after thrombin incubation, while Bcl-2 was decreased. The effects of 3-MA treatment further suggested that autophagy might mediate the partial protective effects of Resveratrol on HPAECs. To observe the effects of Resveratrol in vivo, the authors established a Chronic Thromboembolic Pulmonary Hypertension (CTEPH) model by repeatedly injecting autologous blood clots into a rat's left jugular vein. The results exhibited that Mean Pulmonary Arterial Pressure (mPAP) and vessel Wall Area/Total Area (WA/TA) ratio were both decreased after Resveratrol treatment. Moreover, Resveratrol could reduce the concentration and activity of TF, vWF, P-selectin, and promote these Superoxide Dismutase (SOD) in plasma. Western blot analysis of inflammation, platelet activation, autophagy, and apoptosis-associated proteins in pulmonary artery tissue validated the results in PHAECs. CONCLUSIONS: These findings suggested that reduced autophagy, increased oxidative stress, increased platelet activation, and increased inflammation were involved in CTEPH-induced HPAEC dysfunction and the development of PH, while Resveratrol could improve PAEC dysfunction and PH.


Asunto(s)
Hipertensión Pulmonar , Embolia Pulmonar , Animales , Autofagia , Células Endoteliales , Humanos , Inflamación , Estrés Oxidativo , Arteria Pulmonar , Ratas , Resveratrol , Trombina
7.
Front Med (Lausanne) ; 9: 1050118, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36874949

RESUMEN

Objectives: We developed a postural drainage lithotripsy system (PDLS) that can provide an individualized inversion and overturning angle and uses gravity to remove residual fragments (RFs). This study aimed to evaluate the effect of different targeted calyces on treating multi-site stones in PDLS. Methods: A total of 20 stones with different sizes and diameters of 0-4 mm were placed in the kidney model through ureteroscopy, and 20 stones were evenly scattered in the middle calyx and the lower calyx of the model. The ventral-middle calyx, the dorsal-middle calyx, the ventral-lower calyx, and the dorsal-lower calyx were used as the targeted calyx of PDLS to treat multi-site stones. During treatment, if the stone moved from the starting position of the renal calyx to the ureteropelvic junction, it was recorded as "passing through." The clearance rate was recorded, and the efficacy of different targeted calyxes in the treatment of multiple-site calyx was compared. Each model was treated with four different targeted calyxes, and 20 models were tested 80 times. Results: When the lower calyx was the targeted calyx, the total stone clearance rate was higher than when the middle calyx was the locating calyx (94.5 vs. 64%, P = 0.000), and the result was statistically significant. Conclusions: Choosing the lower calyx as the targeted calyx, we can obtain a better stone clearance rate. However, there is no significant difference between the ventral lower calyx and the dorsal lower calyx.

8.
Biomed Res Int ; 2021: 6372128, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34258270

RESUMEN

INTRODUCTION: This study was aimed to investigate the effects of N-acetylcysteine (NAC) on chronic obstructive pulmonary disease (COPD) and the change of Th17/Treg cytokine imbalance. Material and Methods. A total of 121 patients with stable COPD at the stage of C or D were consecutively enrolled and randomly divided into 2 groups. Patients in the treatment group received NAC granules (0.2 g × 10 bags, 0.4 g each time, 3 times/d) for half a year. The control group was treated with the same amount of placebo therapy. The peripheral blood of the patient was collected and the cytokine, T lymphocyte subsets were detected. RESULTS: We found the oral administration of NAC could regulate Th17/Treg balance to resist inflammation in COPD patients. Serum testing showed that the proportion of Treg in CD4+ T cells has increased and the Th17/Treg ratio has decreased during the NAC treatment. In vitro studies, we found that NAC regulated Th17/Treg balance through Hypoxia Inducible Factor-1α pathway. CONCLUSIONS: Our result could provide new diagnosis and treatment for elderly patients with COPD from the perspective of immunity ideas.


Asunto(s)
Acetilcisteína/farmacología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Inflamación/patología , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/inmunología , Linfocitos T Reguladores/inmunología , Células Th17/inmunología , Acetilcisteína/administración & dosificación , Administración Oral , Anciano , Regulación hacia Abajo/efectos de los fármacos , Femenino , Humanos , Inflamación/sangre , Inflamación/complicaciones , Interleucina-10/sangre , Interleucina-17/sangre , Recuento de Linfocitos , Masculino , Enfermedad Pulmonar Obstructiva Crónica/sangre , Linfocitos T Reguladores/efectos de los fármacos , Células Th17/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos
9.
Comput Math Methods Med ; 2021: 7596343, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34899969

RESUMEN

BACKGROUND: N-Acetylcysteine (NAC) had exerted antioxidation and anti-inflammation effects on chronic obstructive pulmonary disease (COPD) patients. However, its effect in regulating interleukin- (IL-) 18 was not fully understood. This study was designed to evaluate the specific mechanism of NAC regulating IL-18. MATERIALS AND METHODS: A total of 112 COPD patients and 103 health individuals were recruited in the study. Cytokine level in patients' serum was measured by enzyme-linked immunosorbent assay (ELISA). A COPD mouse model was established by administration of lipopolysaccharide (LPS) and cigarette smoke. The expression of cytokines was measured by ELISA and flow cytometry. Inflammasome-related protein was measured by Western blot. RESULT: NAC could effectively improve the immune status of COPD patients as well as the COPD mouse model by downregulating proinflammation and inflammation cytokines including IL-1ß, interferon- (IFN-) γ, tumor necrosis factor- (TNF-) α, and IL-18. It also had the capability to suppress synthesis of IL-18 in macrophage to inhibit the secretion of IFN-γ from natural killer (NK) cells through influencing the inflammasome-related protein in macrophages. CONCLUSION: NAC could effectively inhibit the production of IL-18 by suppressing NLRP3 expression in macrophages to reduce the production of IFN-γ in NK cells.


Asunto(s)
Acetilcisteína/farmacología , Interferón gamma/biosíntesis , Interleucina-18/biosíntesis , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/inmunología , Proteína con Dominio Pirina 3 de la Familia NLR/antagonistas & inhibidores , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/inmunología , Anciano , Animales , Estudios de Casos y Controles , Biología Computacional , Citocinas/sangre , Modelos Animales de Enfermedad , Femenino , Humanos , Interleucina-18/antagonistas & inhibidores , Pulmón/efectos de los fármacos , Pulmón/inmunología , Pulmón/patología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/patología
10.
J Biophotonics ; 14(8): e202100035, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33991071

RESUMEN

As an important biomedical imaging method, endoscopic optical coherence tomography (OCT) is necessary to check its performance regularly. The ordinary plane phantoms are only able to evaluate part of image tangent to the probe. In this research, a spatial resolution estimate method of the endoscope OCT system is proposed. The annular phantom, made by uniformly distributing golden scattered microparticles in polydimethylsiloxane (PDMS), can provide dynamic scanning imaging evaluation of endoscopic OCT system, closer to its actual working status. The point spread function analysis method is used to analyze the imaging results of the annular phantom with the endoscopic OCT system. And many scattered particles are statistically analyzed to determine the spatial resolution of the endoscope OCT system. The method is low in cost, simple and convenient. It is valuable for the development of test standards for endoscope OCT systems.


Asunto(s)
Endoscopía , Tomografía de Coherencia Óptica , Fantasmas de Imagen
11.
J Sep Sci ; 33(19): 2990-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20812229

RESUMEN

Immobilized artificial membrane chromatography stationary phase was prepared by coating soybean phosphatidylcholine (PC) on zirconia-magnesia micro-particles. The stability and chromatographic properties were investigated and compared with the PC-coated silica chromatography stationary phase prepared by the same method. PC-coated zirconia-magnesia chromatography stationary phase was more stable than the silica especially on resisting organic solvents. Hydrophobic action was the main factor for the retention of analyte on the new artificial membrane chromatography stationary phase, and electrostatic interaction had some contribution to retention. In addition, the special interaction between analyte and matrix affected retention greatly. Basic solutes were appropriate to be analyzed on PC-coated zirconia-magnesia stationary phase and acidic solutes were appropriate to be done on the silica one. Hence, the two different matrices artificial membrane stationary phases were perfectly complementary.


Asunto(s)
Óxido de Magnesio/química , Membranas Artificiales , Fosfatidilcolinas/química , Dióxido de Silicio/química , Circonio/química , Cromatografía Liquida/métodos
12.
World J Clin Oncol ; 11(12): 1076-1083, 2020 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-33437669

RESUMEN

BACKGROUND: To investigate the clinicopathological features of endometrial clear cell carcinoma that has invaded the right oviduct with a cooccurring ipsilateral oviduct adenomatoid tumor. CASE SUMMARY: A case of endometrial clear cell carcinoma invading the right oviduct with a cooccurring ipsilateral oviduct adenomatoid tumor was collected and analyzed using pathomorphology and immunohistochemistry. Endometrial clear cell carcinoma cells were distributed in a solid nest, papillary, shoe nail-like, and glandular tube-like distribution. There was infiltrative growth, and tumor cells had clear cytoplasm and obvious nuclear heteromorphism. The cancer tissue was necrotic and mitotic. The cancer tissue invaded the right oviduct. The ipsilateral oviduct also had an adenomatoid tumor. The adenomatoid tumor was arranged in microcapsules lined with flat or cubic cells that were surrounded by smooth muscle tissue. The adenomatoid tumor cells were round in shape. CONCLUSION: Clear cell carcinoma of the endometrium can invade the oviduct and occur simultaneously with tubal adenomatoid tumors. Upon pathological diagnosis, one should pay close attention to distinguishing whether an endometrial clear cell carcinoma is invading the oviduct or whether it is accompanied by an adenomatoid tumor of the oviduct. Immunohistochemistry is helpful to differentiate these two disease entities. Endometrial clear cell carcinomas express Napsin-A and P16 and are negative for estrogen receptor and progesterone receptor. The presence of endometrial clear cell carcinoma does not affect the expression of CK and calretinin in adenomatoid tumors.

14.
Zhongguo Fei Ai Za Zhi ; 22(5): 319-323, 2019 May 20.
Artículo en Zh | MEDLINE | ID: mdl-31109442

RESUMEN

BACKGROUND: Lung cancer is the cancer with the highest morbidity and mortality at home and abroad at present. Using computed tomography (CT) to screen lung cancer nodules is a huge workload. To test the effect of artificial intelligence in automatic identification of lung cancer by using artificial intelligence to find the lung cancer nodules automatically in the chest CT of 1 mm and 5 mm thick. METHODS: 5,000 cases of T1 stage lung cancer patients with 1 mm and 5 mm layer thickness were respectively labeled and learned by computer neural network, the algorithm of forming pulmonary nodules was carried out. 500 cases of chest CT in T1 stage lung cancer patients with 1 mm and 5 mm thickness were tested by artificial intelligence formation, and the sensitivity and specificity were compared with artificial reading. RESULTS: Using artificial intelligence to read chest CT 500 in 5 mm, the sensitivity was 95.20%, the specificity was 93.20%, and the Kappa value of two times repeated read was 0.926,1. For 1 mm chest CT 500 cases, the sensitivity is 96.40%, the specificity is 95.60%, and the Kappa reads two times is 0.938,6. Compared with 5 doctors, the same CT sets with 1 mm thickness were read. The detection rates of artificial intelligence and artificial reading were similar to those of lung cancer nodules and negative control read films, and there was no significant difference between them. In the comparison of the same CT slices with 5 mm thickness, the number of detection of lung cancer nodules by artificial intelligence is better than that of artificial reading, and the sensitivity is higher, but the number of false messages is increased and the specificity is slightly worse. CONCLUSIONS: The automatic learning of early lung cancer chest CT images by artificial intelligence can achieve high sensitivity and specificity of early lung cancer identification, and assist doctors in the diagnosis of lung cancer.


Asunto(s)
Inteligencia Artificial , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patología , Informática Médica/métodos , Humanos , Estadificación de Neoplasias
15.
Chem Commun (Camb) ; 54(17): 2169-2172, 2018 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-29431843

RESUMEN

The encapsulation of a series of metal-terpyridyl complexes in cucurbit[10]uril (CB[10]) in water is described. A strong enhancement of metal-metal and π-π interactions is observed due to double confinement in the large cavity. Furthermore, a linear supramolecular polymer featuring host-enhanced metallophilic interactions in water can be prepared.

16.
J Colloid Interface Sci ; 522: 264-271, 2018 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-29604445

RESUMEN

Monodisperse hollow mesoporous PdCo alloy nanospheres are prepared via a simple galvanic replacement reaction. The as-prepared PdCo hollow nanospheres have small diameter, such as Pd78Co22 nanospheres of diameter about 25 nm and mesoporous shells about 4-5 nm. The Pd78Co22 hollow mesoporous nanospheres possess the largest electrochemical active surface areas (ECSA, 53.91 m2 g-1), mass activity (1488 mA mg-1) and specific activity (2.76 mA cm-2) towards to methanol oxidation relative to the Pd68Co32, Pd92Co8 hollow mesoporous nanospheres and commercial Pd/C catalysts. Moreover, the activity of Pd78Co22 after long-term stability tests is still the best and even better than those of fresh Pd68Co32 and commercial Pd/C catalysts. The PdCo catalysts not only effectively reduce the Pd usage by forming hollow structure, but also fully realize the Pd-Co alloying effects for enhancing the methanol oxidation catalytic performance.

17.
Appl Spectrosc ; 72(9): 1349-1353, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29888949

RESUMEN

Complex refractive index dispersion (CRID) of offset inks is an important spectral property that affects the quality of printing. Due to the strong absorption of offset inks, great difficulty exists when measuring their CRID. In this study, a recently proposed apparatus that can detect the internal reflectance spectra was used to measure the CRID of three strong absorbing offset inks (magenta, yellow, and cyan). Both anomalous dispersion curve and extinction coefficient curve were well determined over the spectral range of 400-750 nm. This study experimentally proves that the apparatus and related method are feasible for the CRID measurement of strong absorbing materials and could serve as a powerful measuring tool for optical parameters.

18.
ACS Appl Mater Interfaces ; 10(26): 22248-22256, 2018 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-29900739

RESUMEN

Flowerlike NiCo2S4 hollow sub-microspheres are synthesized through Cu2O templates to support Pd nanoparticles as high-efficiency catalysts for the hydrogen evolution reaction (HER). The diameter and shell size of NiCo2S4 hollow sub-microspheres are about 400 and 16 nm, respectively. In addition, the surface of the shells is constructed by petallike nanosheets. About 3 nm Pd particles uniformly incorporate with the flowerlike NiCo2S4 hollow sub-microsphere to form the NiCo2S4/Pd heterostructure. The NiCo2S4/Pd catalysts exhibit significantly lower overpotential of only 87 and 83 mV at 10 mA/cm2 for the HER in both acidic and alkaline conditions, respectively, relative to NiCo2S4 (247, 226 mV) and Pd (175, 385 mV) catalysts. Besides, the NiCo2S4/Pd catalysts also exhibit excellent stability of HER in these two conditions. The superior HER performance of NiCo2S4/Pd might be resulted from the unique architecture of metal nanoparticles anchored on the bimetallic sulfide flowerlike hollow sub-microspheres, which could provide high surface area, lots of active sites, strong synergetic effect, and stable structure.

19.
J AOAC Int ; 90(1): 258-62, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17373458

RESUMEN

A procedure for direct determination of trace elements in muscle tissue of hairtail was developed using inductively coupled plasma-atomic emission spectrometry and electrothermal vaporization with slurry sampling. Due to use of polytetrafluoroethylene as the chemical modifier, the vaporization behaviors of analytes from the slurry and the aqueous standard solutions were very similar. In this case, the aqueous standards could be used for the calibration of slurry samples. The main factors influencing this method were studied systematically. The detection limits for Cr, Ni, Zn, Cd, and Pb were 3.1, 10.5, 176, 6.9, and 83 ng/mL, respectively, and the relative standard deviations were less than 10%. The proposed method was applied to the determination of trace Cr, Ni, Zn, Cd, and Pb in hairtail samples with satisfactory accuracy and precision. A certified reference material of mussel (GBW 08571) was analyzed, and good agreement was obtained between the results from the proposed method and certificate values.


Asunto(s)
Músculo Esquelético/química , Oligoelementos/análisis , Animales , Cadmio/análisis , Cromo/análisis , Peces , Plomo/análisis , Níquel/análisis , Sensibilidad y Especificidad , Termodinámica , Volatilización , Zinc/análisis
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