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1.
Artigo em Inglês | MEDLINE | ID: mdl-38924393

RESUMO

OBJECTIVE: The aim of this study was to explore whether machine learning model based on computed tomography (CT) radiomics and clinical characteristics can differentiate Epstein-Barr virus-associated gastric cancer (EBVaGC) from non-EBVaGC. METHODS: Contrast-enhanced CT images were collected from 158 patients with GC (46 EBV-positive, 112 EBV-negative) between April 2018 and February 2023. Radiomics features were extracted from the volumes of interest. A radiomics signature was built based on radiomics features by the least absolute shrinkage and selection operator logistic regression algorithm. Multivariate analyses were used to identify significant clinicoradiological variables. We developed 6 ML models for EBVaGC, including logistic regression, Extreme Gradient Boosting, random forest (RF), support vector machine, Gaussian Naive Bayes, and K-nearest neighbor algorithm. The area under the receiver operating characteristic curve (AUC), the area under the precision-recall curves (AP), calibration plots, and decision curve analysis were applied to assess the effectiveness of each model. RESULTS: Six ML models achieved AUC of 0.706-0.854 and AP of 0.480-0.793 for predicting EBV status in GC. With an AUC of 0.854 and an AP of 0.793, the RF model performed the best. The forest plot of the AUC score revealed that the RF model had the most stable performance, with a standard deviation of 0.003 for AUC score. RF also performed well in the testing dataset, with an AUC of 0.832 (95% confidence interval: 0.679-0.951), accuracy of 0.833, sensitivity of 0.857, and specificity of 0.824, respectively. CONCLUSIONS: The RF model based on clinical variables and Rad_score can serve as a noninvasive tool to evaluate the EBV status of gastric cancer.

2.
Br J Radiol ; 96(1150): 20230239, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37660472

RESUMO

OBJECTIVE: The purpose of this meta-analysis was to determine the value of dynamic contrast-enhanced-MRI (DCE-MRI) and diffusion-weighted imaging (DWI) in evaluating the pathological response of muscle invasive bladder cancer (MIBC) to neoadjuvant chemotherapy (NAC), and further indirectly compare the diagnostic performance of DCE-MRI and DWI. METHODS: Literatures associated to DCE-MRI and DWI in the evaluation of pathological response of MIBC to NAC were searched from PubMed, Cochrane Library, web of science, and EMBASE databases. The quality assessment of diagnostic accuracy studies 2 tool was used to assess the quality of studies. Pooled sensitivity (SE), specificity (SP), positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and the area under the receiver operating characteristic curves (AUC) with their 95% confidence intervals (CIs) were calculated to evaluate the diagnostic performance of DCE-MRI and DWI in predicting the pathological response to NAC in patients with MIBC. RESULTS: There were 11 studies involved, 6 of which only underwent DCE- MRI examination, 4 of which only underwent DWI examination, and 1 of which underwent both DCE- MRI and DWI examination. The pooled SE, SP, PLR, NLR, DOR of DCE-MRI were 0.88 (95% CI: 0.78-0.93), 0.88 (95% CI: 0.67-0.96), 7.4 (95% CI: 2.3-24.2), 0.14 (95% CI: 0.07-0.27), and 53 (95% CI: 10-288), respectively. The pooled SE, SP, PLR, NLR, DOR of DWI were 0.83 (95% CI: 0.75-0.88), 0.88 (95% CI: 0.81-0.93), 7.1 (95% CI: 4.3-11.7), 0.20 (95% CI: 0.14-0.28), and 36 (95% CI:18-73), respectively. The AUCs of SROC curve for DCE-MRI and DWI were 0.93 (95% CI: 0.91-0.95) and 0.92 (95% CI: 0.89-0.94), respectively. There were no significant differences between DWI and DCE-MRI for SE, SP, and AUC. CONCLUSION: This meta-analysis demonstrated high diagnostic performance of both DCE-MRI and DWI in predicting the pathological response to NAC in MIBC. DWI might be a potential substitute for DCE-MRI, with no significant difference in diagnostic performance between the two. However, caution should be taken when applying our results, as our results were based on indirect comparison. ADVANCES IN KNOWLEDGE: No previous studies have comprehensively analysed the value of DCE-MRI and DWI in evaluating the pathological response to NAC in MIBC. According to the current study, both DCE-MRI and DWI yielded high diagnostic performance, with the AUCs of 0.93 and 0.92, respectively. Indirect comparison no significant difference in the diagnostic performanceof DCE-MRI and DWI.


Assuntos
Terapia Neoadjuvante , Neoplasias , Humanos , Terapia Neoadjuvante/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Curva ROC , Músculos , Sensibilidade e Especificidade
3.
Radiol Med ; 128(11): 1296-1309, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37679641

RESUMO

OBJECTIVE: Microvascular invasion (MVI) is a significant adverse prognostic indicator of intrahepatic cholangiocarcinoma (ICC) and affects the selection of individualized treatment regimens. This study sought to establish a radiomics nomogram based on the optimal VOI of multi-sequence MRI for predicting MVI in ICC tumors. METHODS: 160 single ICC lesions with MRI scanning confirmed by postoperative pathology were randomly separated into training and validation cohorts (TC and VC). Multivariate analysis identified independent clinical and imaging MVI predictors. Radiomics features were obtained from images of 6 MRI sequences at 4 different VOIs. The least absolute shrinkage and selection operator algorithm was performed to enable the derivation of robust and effective radiomics features. Then, the best three sequences and the optimal VOI were obtained through comparison. The MVI prediction nomogram combined the independent predictors and optimal radiomics features, and its performance was evaluated via the receiver operating characteristics, calibration, and decision curves. RESULTS: Tumor size and intrahepatic ductal dilatation are independent MVI predictors. Radiomics features extracted from the best three sequences (T1WI-D, T1WI, DWI) with VOI10mm (including tumor and 10 mm peritumoral region) showed the best predictive performance, with AUCTC = 0.987 and AUCVC = 0.859. The MVI prediction nomogram obtained excellent prediction efficacy in both TC (AUC = 0.995, 95%CI 0.987-1.000) and VC (AUC = 0.867, 95%CI 0.798-0.921) and its clinical significance was further confirmed by the decision curves. CONCLUSION: A nomogram combining tumor size, intrahepatic ductal dilatation, and the radiomics model of MRI multi-sequence fusion at VOI10mm may be a predictor of preoperative MVI status in ICC patients.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Nomogramas , Estudos Retrospectivos , Invasividade Neoplásica , Imageamento por Ressonância Magnética/métodos , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/cirurgia , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/cirurgia
4.
J Hazard Mater ; 435: 128992, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35489317

RESUMO

Perylene diimide and its derivatives are promising photocatalysts for clean and efficient production, but their practical application in the field of photocatalysis is still limited by the rapid photogenerated charge recombination. In this work, the confined photocatalysts were synthesized by using a gas-phase self-assembly method and comparing the morphology and photocatalytic properties of different photocatalysts after the confinement of carbon nanotubes. The confinement effect of carbon nanotubes acts to stabilize perylene diimide. Electrostatic interaction formed by a wide range of dispersion forces is dominant in the process of stabilization. Benefitting from the three-dimensional electron transfer pathway formed by the conjugation of perylene diimide with a large number of π electrons to the carbon nanotubes plane, the confined photocatalyst shows the pseudo-first-order kinetic constant k of 1.106 h-1 for the photocatalytic degradation of diclofenac under light, which is 6.11 times higher than that of perylene diimide. The electron transfer created an internal electric field at the interface from carbon nanotubes to perylene diimide, which greatly accelerated the separation of photogenerated electron-hole pairs and improved the photocatalytic activity. This study further expands the applicability of perylene diimide in the field of photocatalysis and provides a new approach for water environment treatment.


Assuntos
Nanotubos de Carbono , Perileno , Purificação da Água , Catálise , Diclofenaco
5.
Nat Commun ; 12(1): 4152, 2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34230482

RESUMO

Major challenges encountered when developing manganese-based materials for ozone decomposition are related to the low stability and water inactivation. To solve these problems, a hierarchical structure consisted of graphene encapsulating α-MnO2 nanofiber was developed. The optimized catalyst exhibited a stable ozone conversion efficiency of 80% and excellent stability over 100 h under a relative humidity (RH) of 20%. Even though the RH increased to 50%, the ozone conversion also reached 70%, well beyond the performance of α-MnO2 nanofiber. Here, surface graphite carbon was activated by capturing the electron from inner unsaturated Mn atoms. The excellent stability originated from the moderate local work function, which compromised the reaction barriers in the adsorption of ozone molecule and the desorption of the intermediate oxygen species. The hydrophobic graphene shells hindered the chemisorption of water vapour, consequently enhanced its water resistance. This work offered insights for catalyst design and would promote the practical application of manganese-based catalysts in ozone decomposition.

6.
Abdom Radiol (NY) ; 46(2): 749-756, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32671439

RESUMO

The purpose of this study is to assess the relative clinical efficacy of treating malignant hilar biliary obstruction (MHBO) via percutaneous unilateral or bilateral metal stenting. Relevant articles up to December 2019 were identified within the Web of science, Pubmed, Embase, and Cochrane Library databases. Stent dysfunction served as the primary endpoint, while we assessed technical success, clinical success, early and late complication incidence, and overall survival as secondary outcomes. Pooled odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated for dichotomous variables. Hazard ratio (HR) with 95% CI were determined for overall survival. This meta-analysis included seven studies. Six studies were non-randomized controlled trials (RCTs) and one study was a RCT. A total of 888 MHBO patients underwent either percutaneous unilateral (n = 376) or bilateral (n = 512) metal stenting in these seven studies. We detected no significant differences in stent dysfunction rates (OR 0.97; 95% CI 0.67, 1.41, P = 0.89), technical success rates (OR 1.10; 95% CI 0.53, 2.29, P = 0.81), clinical success rates (OR 0.72; 95% CI 0.43, 1.22, P = 0.22), early complication rates (OR 0.82; 95% CI 0.34, 1.98, P = 0.66), late complication rates (OR 0.87; 95% CI 0.29, 2.63, P = 0.81), or overall survival (HR: 0.99; 95% CI 0.83, 1.17, P = 0.88) between unilateral and bilateral groups. Funnel plots demonstrated no obvious publication bias of these primary and secondary endpoints. From a clinical perspective, percutaneous unilateral and bilateral metal stenting are similarly effective for treatment of patients with MHBO.


Assuntos
Neoplasias dos Ductos Biliares , Colestase , Neoplasias , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Colestase/diagnóstico por imagem , Colestase/terapia , Drenagem , Humanos , Metais , Stents , Resultado do Tratamento
7.
Eur J Gastroenterol Hepatol ; 32(7): 769-778, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31834053

RESUMO

Recent studies have reported albumin-bilirubin (ALBI) grade affected the prognosis of patients with hepatocellular carcinoma (HCC). To more precisely evaluate the relationship among the ALBI grade and the prognosis of patients with HCC after liver resection. We systematically retrieved articles from PubMed, Web of Science, Cochrane Library, and CNKI. The prognostic value of ALBI grade on overall survival (OS) and recurrence-free survival (RFS) of patients with HCC after liver resection was evaluated by pooled hazard ratio (HR) with 95% confidence interval (CI).Through multiple databases search, we enrolled 20 high-quality studies with 11365 patients, regarding the association between the ALBI grade and the prognosis of patients with HCC after liver resection. Our results showed that higher ALBI grade is associated with poored OS (HR, 1.64; 95% CI: 1.51-1.78; P < 0.001; I = 24.9%) and RFS (HR, 1.42; 95% CI: 1.26-1.59; P < 0.001; I = 0). Moreover, subgroup analysis showed the significant correlation between ALBI grade and poor long-term survival was not altered in different geographical areas, sample sizes, follow-up duration, and quality scores. The ALBI grade may be as effective predictive biomarkers for prognosis in patients with HCC after liver resection.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Bilirrubina , Carcinoma Hepatocelular/cirurgia , Humanos , Neoplasias Hepáticas/cirurgia , Prognóstico , Estudos Retrospectivos , Albumina Sérica
8.
Environ Pollut ; 257: 113577, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761595

RESUMO

A self-assembly method was adopted to synthesize loading architecture of ZnO/g-C3N4 heterojunction composites by hybridization of g-C3N4 nanosheets and ZnO nanoparticles utilizing a refluxing method at a low temperature. More importantly, we provided a novel route to regulate the π-π restacking thickness of the g-C3N4 nanosheets among ZnO/g-C3N4 composites by the controlling the refluxing time in the ethanol solution, which can optimize the surface hybrid structure, optical response and photocatalytic activity. Among all of samples, ZnO/g-C3N4 composites with a refluxing 12 h showed the enhancement of photocatalytic activity. The enhanced visible light photocatalytic activity of ZCN-12 composites can be ascribed to the synergistic effects of the construction of hybrid structures, reduction of structural defects of g-C3N4 nanosheets and suitable π-π restacking g-C3N4 nanosheets loading thickness.


Assuntos
Grafite , Nanocompostos/química , Compostos de Nitrogênio , Óxido de Zinco , Catálise , Grafite/química , Luz , Tamanho da Partícula , Processos Fotoquímicos
9.
ACS Nano ; 12(8): 7638-7646, 2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-30060665

RESUMO

Interlayer friction between the atomic planes of 2D materials and heterostructures is a promising probe of the physics in their interlayer couplings and superlubricity. However, it is still challenging to measure the interlayer friction between well-defined 2D layers. We propose an approach of thermally assisted mechanical exfoliation and transfer to fabricate various 2D flake-wrapped atomic force microscopy (AFM) tips and to directly measure the interlayer friction between 2D flakes in single-crystalline contact. First, superlubricity between different 2D flakes and layered bulk materials is achieved with a friction coefficient as low as 10-4. The rotation angle dependence of superlubricity is observed for friction between graphite layers, whereas it is not observed between graphite and h-BN because of the incommensurate contact of the mismatched lattices. Second, the interlayer lateral force map between ReS2 layers is measured with atomic resolution, showing hexagonal patterns, as further verified by theoretical simulations. The tribological system constructed here offers an experimental platform to study interlayer couplings and friction between 2D flakes and layered bulk materials.

10.
Environ Sci Technol ; 52(15): 8684-8692, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-29968461

RESUMO

α-MnO2 is a promising material for ozone catalytic decomposition and the oxygen vacancy is often regarded as the active site for ozone adsorption and decomposition. Here, α-MnO2 nanowire with tunable K+ concentration was prepared through a hydrothermal process in KOH solution. High concentration K+ in the tunnel can expand crystal cell and break the charge balance, leading to a lower average oxidation state (AOS) of Mn, which means abundant oxygen vacancy. DFT calculation has also proven that the samples with higher K+ concentration exhibit lower formation energy for oxygen vacancy. Due to the enormous active oxygen vacancies existing in the α-MnO2 nanowire, the lifetime of the catalyst (corresponding to 100% ozone removal rate, 25 °C) is increased from 3 to 15 h. The FT-IR results confirmed that the accumulation of intermediate oxygen species on the catalyst surface is the main reason why it is deactivated after long time reaction. In this work, the performance of the catalyst has been improved because the abundant active oxygen vacancies are fabricated by the electrostatic interaction between oxygen atoms inside the tunnels and the introduced K+, which offers us a new perspective to design a high efficiency catalyst and may promote manganese oxide for practical ozone elimination.


Assuntos
Ozônio , Catálise , Oxirredução , Oxigênio , Espectroscopia de Infravermelho com Transformada de Fourier
11.
Small ; 12(32): 4370-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27392122

RESUMO

A polyaniline (PANI)/carbon nitride nanosheets (CNNS) composite hydrogel with 3D hierarchical nanostructure is synthesized via in situ polymerization. The 3D hierarchical structure is robust and stable, making the composite hydrogel separation-free and easy to recycling. It is highly excellent in removing organic pollutant for PANI/CNNS composite hydrogel on account of the cooperation of adsorptive preconcentration and the following photocatalytic oxidation. Pollutants are first adsorbed and concentrated into the 3D hierarchical nanostructure of the composite hydrogel. Then the pollutants are in situ oxidized via photocatalysis. The promoted photocatalytic performance can be mainly ascribed to the outstanding interfacial charge separation and photoelectrochemical performance. A new idea of the construction of 3D hierarchical photocatalysts is presented, which can be applied in the sustainability field.

12.
Adv Mater ; 28(33): 7284-90, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27311128

RESUMO

A self-assembled perylene-3,4,9,10-tetracarboxylic diimide(PDINH) supramolecular system consisting of all-organic PDINH molecule building blocks through non-covalent interactions works as a visible light photocatalyst with high activity.

13.
Sci Rep ; 6: 19347, 2016 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-26777609

RESUMO

Bi2WO6 as a high visible-light-driven catalyst has been aroused broad interest. However, it can only be excitated by the light with λ < 450 nm and the solar energy utilization need to be improved. Here, the wide-range-visible photoresponse Bi2WO6-x nanoplates were fabricated by introducing surface oxygen vacancies through the controllable hydrogen reduction method. The visible photoresponse wavelength range is extended from 450 nm to more than 600 nm. In addition, the photocatalytic activity of Bi2WO6-x is also increased and is 2.1 times as high as that of pristine Bi2WO6. The extending of the photoresponse range and the enhancement of the photoactivity both can be attributed to the surface-oxygen-vacancy states. This is because surface-oxygen-vacancy states generated above and partly overlapping of with the valence band (VB) will result in the rising of valence band maximum (VBM), thus broadening the VB width. This approach is proposed to develop many types of wide-range-visible optical materials and to be applicable to many narrow and wide bandgap materials.

14.
Nanoscale ; 7(33): 13943-50, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26221909

RESUMO

Highly dispersed BiPO4 with surface oxygen vacancies was synthesized via a solvothermal-calcination method. It can disperse uniformly in water for more than three days and the optimum photocatalytic activity of this highly dispersed BiPO4 was more than twice as high as that of Degussa P25 due to the oxygen vacancies. The high dispersibility is attributed to a layer of organic matter formed on the surface of BiPO4via the solvothermal approach. Most of the organic matter can be removed by calcination at 450 °C, but a small amount remains, thus the calcined BiPO4 retained its high dispersibility. This high dispersibility maintains a good contact between BiPO4 and the pollutants, resulting in the efficient removal of the pollutants by BiPO4. Besides, calcination at 450 °C also induced the formation of oxygen defects in BiPO4, which promotes the separation of photogenerated charge carriers and thus improves the photocatalytic activity of BiPO4.

15.
Small ; 11(13): 1512-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25504858

RESUMO

Nanoframes (NFs) are created in situ on reduced graphene oxide (rGO) through confining the evolutions of precursor nanosheets, such as ZnS(EN)0.5 (EN = ethylenediamine), and nanoparticles within quasi-two-dimensional spaces generated from graphene oxide. The resultant composites of ZnS-NF@rGO exhibit excellent photocurrent responses. This work provides a new strategy to synthesize and modulate nanostructures and nanomaterials for rGO composites.

16.
Phys Chem Chem Phys ; 16(47): 26314-21, 2014 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-25367447

RESUMO

A visible-light-sensitive Bi2MoO6-BiOCl heterojunction photocatalyst was synthesized via a hydrothermal process. The as-prepared Bi2MoO6-BiOCl composite shows an irregular multi-plate structure with length ranging from 100 nm to 1 µm, indicating a possibility of the plate-on-plate structure by placing Bi2MoO6 and BiOCl nanoplates over each other. The Bi2MoO6-BiOCl photocatalyst not only had a good visible-light photocatalytic performance, but also exhibited higher photocatalytic activity than pure BiOCl and Bi2MoO6. The optimal Bi2MoO6 content for the photocatalytic activity of the Bi2MoO6-BiOCl composites is 30%. Compared to pure Bi2MoO6 the photoactivity of the Bi2MoO6-BiOCl composites is almost 2.0 times higher for the RhB photodegradation, and 1.5 times higher for the phenol photodegradation under visible light irradiation. The photocatalytic mechanism was elucidated via active species trapping experiments and ESR. The ˙OH and ˙O2(-) played the key roles in the degradation of RhB via the Bi2MoO6-BiOCl composite. Finally, the possible charge transfer mechanism of the enhanced visible light photocatalytic activity was proposed.

17.
Phys Chem Chem Phys ; 16(9): 4236-41, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24452515

RESUMO

A facile synthesis method was developed based on the seed-mediated growth to get the narrow dispersed silver nanoparticles with controllable sizes ranging from 20 nm to larger than 120 nm. Environmentally friendly glucose acts as a reducing agent. Because of its weak reducing ability, the secondary nucleation is prevented in the seed-mediated growth, and the size of silver nanoparticles can be tuned continuously by the continuous addition of reactants. Controlling the supersaturation level is critical to suppress both the nucleation and Ostwald ripening, which can be realized by carefully controlling the addition rate of the reactants. We also set up a convenient method to determine the size and size-distribution of silver nanoparticles from the size-dependent absorption spectra of the colloids, and optimize the growth parameters using this method to get narrow dispersed silver nanoparticles.

18.
Langmuir ; 29(9): 3097-105, 2013 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-23419119

RESUMO

ZnO1-x/graphene hybrid photocatalyst was prepared via a facile in-situ reduction of graphene oxide and ZnO1-x surface defect oxide. The hybrid photocatlayst showed enhanced photocatalytic activity for the photodegradation of methylene blue. The photocorrosion of ZnO1-x was successfully inhibited by graphene hybridation. ZnO1-x/graphene hybrid photocatalyst with 1.2 wt % graphene showed the optimized photocatalytic activity. The photocatalytic activity of ZnO1-x/graphene-1.2 wt % under visible and UV light was about 4.6 and 1.2 times that of ZnO1-x sample, respectively. The photocurrent intensity of ZnO1-x under visible and UV light irradiation can be enhanced by 2 and 3.5 times by graphene hybridization. The enhancement of photocatalytic activity and photocurrent intensity in ZnO1-x/graphene was attributed to the synergistic effect between graphene and ZnO1-x for high separation efficiency of photoinduced electron-hole pairs mainly resulting from the promotion of HOMO orbit of graphene and the Oi″ defect level of ZnO1-x in ZnO1-x/graphene.


Assuntos
Grafite/química , Oxigênio/química , Fotólise , Óxido de Zinco/química , Anticorpos Catalíticos , Azul de Metileno/química , Fenômenos Ópticos , Propriedades de Superfície
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(8): 2274-7, 2011 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-22007432

RESUMO

Reference sample was prepared by masterbatch method, containing heavy metals with known concentration of electronic information products (plastic), the repeatability and precision were determined, and reference sample preparation procedures were established. X-Ray fluorescence spectroscopy (XRF) analysis method was used to determine the repeatability and uncertainty in the analysis of the sample of heavy metals and bromine element. The working curve and the metrical methods for the reference sample were carried out. The results showed that the use of the method in the 200-2000 mg x kg(-1) concentration range for Hg, Pb, Cr and Br elements, and in the 20-200 mg x kg(-1) range for Cd elements, exhibited a very good linear relationship, and the repeatability of analysis methods for six times is good. In testing the circuit board ICB288G and ICB288 from the Mitsubishi Heavy Industry Company, results agreed with the recommended values.

20.
J Nanosci Nanotechnol ; 10(3): 1829-33, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20355582

RESUMO

We demonstrated a simple but general method to prepare large-area flexible nanocomposites with oriented gold nanorods (GNRs) embedded in polyvinyl alcohol (PVA) film by directly introducing a GNR colloidal solution into a PVA aqueous solution and using solid-state drawing techniques. The optical property of the nanocomposite exhibits a strong dependence on the angle between the polarization of the incident light and the drawing direction of the nanocomposite film. The color of the composite film can be intelligently tuned and displays red and blue when the light polarization is switched parallel to and perpendicular to the drawing direction, respectively. These composite films have promise for application in a single electrooptical device.

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