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1.
Anal Methods ; 15(42): 5589-5597, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37850367

RESUMO

Through electrochemical polymerization using L-glutamic acid (L-Glu) as a template and 4,6-diaminoresorcinol as a functional monomer, an enzyme-free molecularly imprinted polymer (MIP) based L-Glu sensor with multi-walled carbon nanotubes (MWCNTs) decorated on a glassy carbon electrode (GCE), namely G-MIP/MWCNTs/GCE, was developed in this work. The reaction conditions were optimized as follows: electrochemical polymerization of 23 cycles, pH of 3.0, molar ratio of template/monomer of 1 : 4, volume ratio of elution reagents of acetonitrile/formic acid of 1 : 1, and elution time of 2 min. The prepared materials and molecularly imprinted polymer were characterized by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) as well as electrochemical methods. The electrochemical properties of different electrodes were investigated via differential pulse voltammetry (DPV), showing that the electrode of G-MIP/MWCNTs/GCE exhibited excellent catalytic oxidation activity towards L-Glu. A good linear relationship between peak-currents and L-Glu concentrations in a range from 1.00 × 10-8 to 1.00 × 10-5 mol L-1 was observed, with a detection limit of 5.13 × 10-9 mol L-1 (S/N = 3). The imprinted sensor possesses excellent selectivity, high sensitivity, and good stability, which have been successfully applied for the detection of L-Glu in pig serum samples with a recovery rate of 97.4-105.5%, being comparable to commercial high-performance liquid chromatography, demonstrating a simple, rapid, and accurate way for the determination of L-Glu in the fields of animal nutrition and biomedical engineering.


Assuntos
Impressão Molecular , Nanotubos de Carbono , Suínos , Animais , Polímeros Molecularmente Impressos , Nanotubos de Carbono/química , Ácido Glutâmico , Impressão Molecular/métodos , Eletrodos
2.
Chem Commun (Camb) ; 59(62): 9501-9504, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37449388

RESUMO

A novel uranyl organic framework (U-hdpcp) based on flexible cyclic triphosphazene polycarboxylate ligands was prepared, which possesses the ability to sense aromatic aldehyde solutions (benzaldehyde, salicylaldehyde and 2-bromobenzaldehyde) and nitro compounds (2,4,6-trinitrophenol, 2,4-dinitrophenol and o-nitrophenol). A fluorescent thin film based on U-hdpcp@PVA with the ability to sense aldehyde vapors was prepared via a spin coating method. The work expands the library of UOF materials based on large-sized carboxylic acid ligands and demonstrates promising applications in the field of fluorescent sensors.

3.
Inorg Chem ; 61(49): 19951-19960, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36426639

RESUMO

Three new triazine compounds [Co1.5(H3TDPAT)(H2O)3]·6H2O (1), [Co2(TCPT)(µ2-H2O)2]·OH (2), and [Ni3(TCPT)]·3OH (3) were designed and synthesized via the reaction of the symmetrical triazine ligand connected by C-N-C and C-O-C bonds with triazine poly(carboxylic acid)s ligands as the side arms: H6TDPAT (H6TDPAT = 2,4,6-tris(3,5-dicarboxylphenylamino)-1,3,5-triazine) and H3TCPT (H3TCPT = 2,4,6-tris(4-carboxyphenoxy)-1,3,5-triazine) as well as the corresponding metal salts under the solvothermal condition. Three triazine polycarboxylate frameworks were characterized by elemental analysis, infrared spectroscopy, ultraviolet spectroscopy, thermogravimetric analysis, X-ray powder diffraction, and solid fluorescent spectra in detail. The structural analysis results showed that the three-dimensional porous cage framework of compound 1 was constructed by three different polyhedral cages connected with [Co(COO)4(H2O)2] building blocks. One of the compounds, 2, is formed by twin propeller Co2(µ2-H2O)(COO)3 building blocks connecting two-dimensional layers and the intermolecular π-π interactions involved the triazine rings between the layers. While the structure of compound 3 is similar to that of 2, assembly is by Ni(COO)3 building blocks and adjacent layers of the face-to-face π-π interaction between the triazine rings. In order to explore functional properties, the catalytic reduction of p-nitrophenol (PNP) of compounds 1-3 was investigated. They exhibit excellent catalytic activity of more than 95% for reduction of PNP with a dose of 2.5 mg of the compounds.


Assuntos
Dióxido de Carbono , Triazinas , Catálise , Nitrofenóis
4.
Anal Methods ; 14(29): 2866-2875, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35856488

RESUMO

In this study, zinc oxide@cupric oxide hollow nanospheres (ZnO@CuO HNS, 330 nm in diameter) were successfully prepared by a hard-template method using amino-phenolformaldehyde resin spheres (APF) as the templates. A new type of thin-film gas sensor toward hydrogen sulfide (H2S) was fabricated by means of drop-coating on the gold electrode of an alumina ceramic tube. The microstructure and morphology of the nanosphere composites were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the gas-sensing performance of the composites toward the detection of H2S were investigated. The ZnO@CuO nanocomposite with a hollow structure exhibited good gas-sensing properties. Under the optimum operating temperature of 260 °C, ambient temperature of 30 °C, and ambient humidity of 70%, the linear response of the sensor to H2S was in the concentration range of 0.1-100 ppm, and its detection limit reached 0.0611 ppm, with a quick response time of 78 s. Also, the sensor possessed good repeatability, selectivity, and stability. The long-term stability and run duration of such sensors were pronounced, with only a 1.9% reduction in the signal after the continuous monitoring of H2S gas in a pig farm for 18 months using Alibaba's cloud remote transmission system, which presents an important practical application prospect in atmosphere environment monitoring on livestock-raising fields.


Assuntos
Sulfeto de Hidrogênio , Nanosferas , Óxido de Zinco , Animais , Cobre , Sulfeto de Hidrogênio/química , Suínos , Óxido de Zinco/química
5.
Inorg Chem ; 61(26): 10066-10078, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35729692

RESUMO

A series of novel Cd metal-organic frameworks (MOFs) (1-9) with different extended spacers with seven kinds of the aliphatic dicarboxylic acids as secondary building linkers based on N,N'-di(4-pyridylacylamino)-1,4,5,8-naphthalenediimide (NDI-A) have been designed and synthesized by changing the volume ratio of solvents under solvothermal conditions. In addition, the secondary building linkers of aliphatic dicarboxylic acids have different spacer lengths, resulting in different structures of complexes 1-9. So, their packing structures are affected by the degree of distortion of the NDI-A ligand, the different aliphatic dicarboxylic acids ligands, and the hydrogen-bonding patterns. Complexes 1-9 showed stimuli-responsive emission tuned by different aliphatic dicarboxylic acids with extended length spacers under UV light irradiation, accompanied by the color change from light orange to dark brown, and achieved reversible photochromic under heating, which indicates that they could serve as secret erasable inks. Moreover, complexes 1-9 exhibited selective vaporchromic behavior to methylamine (MA), and the vaporchromic sample could be recovered after washing with MeOH. It is worth noting that the preparation of poly(vinyl alcohol) (PVA)-NDI-MOF films enables the photochromic and vaporchromic properties of complexes 1-9 to apply in practice. In addition, complexes 1-9 exhibited good fluorescence properties as sensing probes toward 2,4,6-trinitrophenol (TNP) with lower limits of detection. In short, this work provides a broad field to explore the creative NDI-MOF materials with photoactive and luminescent properties.

6.
World J Clin Cases ; 10(6): 1937-1945, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35317135

RESUMO

BACKGROUND: Vascular complications of transradial percutaneous coronary intervention (PCI) are rare and usually occur at the access site below the elbow. Life-threatening vascular complications during transradial PCI therapy, such as vessel perforation and dissection in the brachiocephalic, subclavian, internal mammary, and thyrocervical arteries, are rarely reported. Subclavian artery bleeding is a potentially serious complication of vascular interventional procedures leading to tracheal obstruction, hemothorax, respiratory failure, hemorrhagic shock, and death if not diagnosed early and treated promptly. CASE SUMMARY: A male patient with typical angina pectoris underwent coronary angiography and stent implantation. During the procedure, the patient felt pharyngeal pain and tightness, which we mistook for myocardial ischemia. After PCI, swelling in the right neck and supraclavicular area was observed. The patient experienced dyspnea, emergency endotracheal intubation was performed, and then a sudden drop in blood pressure was observed. Ultrasound and contrast-enhanced computed tomography scans demonstrated a cervical hematoma severely compressing the trachea due to subclavian artery bleeding. Brachiocephalic angiography revealed a vascular injury site at the root of the right subclavian artery at the intersection of the right common carotid artery. A covered stent was deployed to the right subclavian artery with successful sealing of the perforation, and a bare stent was implanted in the junction of the right common carotid and brachiocephalic arteries to prevent obstruction of blood flow to the brain. CONCLUSION: Subclavian artery bleeding is a lifethreatening complication of PCI. Early prevention, rapid recognition, and prompt treatment may improve the prognosis.

7.
Dalton Trans ; 51(14): 5457-5470, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35333277

RESUMO

The controllable design, synthesis and functional properties of a series of triazine tetratopic carboxylic MOFs have always been hotspots and challenges for research. Based on the characterization of the C-Cl bond on the triazine skeleton being easily substituted by some functional groups, we designed and synthesized a series of triazine tetratopic carboxylic Cu(II) and Zn(II) MOFs via the reaction of Cu(NO3)2·2.5H2O and ZnSO4·7H2O, as well as triazine tetratopic carboxylic H4TDBA-Cl (H4TBDA-Cl = 5,5'-((6-chloro-1,3,5-triazine-2,4-diyl)bis(azanediyl))diisophthalic acid) under hydrothermal conditions. During the process of synthesizing, the C-Cl bond on the triazine skeleton of the ligand was substituted with different groups, which formed the complexes ([Cu2(TBDA-Cl)(H2O)·10DMF·30H2O]n) (DMF = N,N-dimethylformamide) (1), N(Me)2 -[(CH3)2NH2]4·[Zn3(HTBDA-N)2(SO4)2]n (2) and H ([Cu2(TBDA-H)(H2O)]n) (3), respectively. It is worth noting that the in situ substitution reaction occurred for complexes 2 and 3 during the process of synthesis. Also, the structural analysis showed that the molecules in complexes 1-3 were connected with different building blocks to form different three-dimensional structures. We performed iodine adsorption experiments on the three complexes and found that there was a significant relationship between the structural configuration and adsorption behaviour. The results showed that the complex 1 with the Cl atom on the triazine skeleton could have a boosting effect on adsorption with iodine. It displayed a remarkable adsorption effect for iodine (in the solution of water: 7.6 g g-1 and in the solution of cyclohexane: 548.2 mg g-1). In addition, it also displayed the adsorption effect for JGB dye (204.9 mg g-1). For complex 2, it displayed an uptake effect for iodine in the solution of cyclohexane (529 mg g-1). The possible adsorption mechanism was also investigated. By comparison, we found that chlorine atoms could play an important role in the adsorption processes. The adsorption capacity of complex 1 (containing the chlorine atom in the structure) was much higher than that for complex 3.

8.
Inorg Chem ; 60(11): 7887-7899, 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34024091

RESUMO

Three new metal-organic frameworks (MOFs), namely, [Pb7(TTPCA)4Cl2]·3H2O (1), [Pb7(TTPCA)4(DMA)2(HCOO)2]·H2O (2), and [Pb4(TTPCA)3]·3DMF·2H2O·H3O (3), were synthesized by the H3TTPCA ligand [H3TTPCA = 1,1',1″-(1,3,5-triazine-2,4,6-triyl)-tripiperidine-4-carboxylic acid], with lead(II) nitrate under solvothermal conditions. They were characterized by CHN analysis, IR spectroscopy, UV-vis spectroscopy, and single-crystal and powder X-ray diffraction. In addition, their thermogravimetric analysis and fluorescence properties were studied. Compounds 1-3 were 3D MOF structures with different Pbx(COO)y clusters: ([Pb7(COO)12Cl2]), ([Pb7(COO)12]), and [Pb8(COO)18]. Fluorescence detection of compounds 1-3 shows that they can act as excellent sensors of nitrophenols with a low limit of detection and a high quenching constant.

9.
Chemistry ; 27(37): 9605-9619, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-33871899

RESUMO

Photoresponsive materials are a key part of the age of smart technology that have potential in a broad range of applications. Coordination networks (CNs) are widely used due to their designability and stability. In this work, three novel alkaline earth metal coordination networks (AEM-CNs): [Mg(CMNDI)(H2 O)2 ], [Ca(CMNDI)(H2 O)2 ]⋅H2 O, and [Sr(CMNDI)(H2 O)(DMF)] with fsl, cds, and scn topology nets were synthetized via N,N'-bis(carboxymethyl)-1,4,5,8-naphthalenediimide (H2 CMNDI); the scn net is not found in the Reticular Chemistry Structure Resource or ToposPro. The reusable and sensitive photochromic properties of the three CNs enable them to be used as secret inks or ultraviolet detectors. In addition, the CNs also exhibited reusable photoluminescent turn-off toward the drug molecules, balsalazide disodium (Bal.) and colchicine (Col.), with good limits of detection of 0.16 and 0.70 µM. To the best of our knowledge, this is the first study of a fluorescence sensor for Bal. Thus, the AEM-CNs provide a design idea for integrated photoresponsive materials that could be further improved in the near future by further study.


Assuntos
Metais Alcalinoterrosos
10.
World J Clin Cases ; 9(4): 951-959, 2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33585644

RESUMO

BACKGROUND: Pheochromocytoma is a rare catecholamines-secreting tumor arising from chromaffin cells in the adrenal medulla. It classically presents with paroxysmal hypertension, headaches, palpitations, sweating, and metabolic disorders. Atypical presentations such as acute myocardial infarction, heart failure, cardiomyopathy, stroke, and transient erythrocytosis have been infrequently documented. CASE SUMMARY: We describe the case of a 72-year-old man diagnosed with pheochromocytoma presenting with non-ST segment elevation myocardial infarction, heart failure, and transient erythrocytosis with nonobstructed coronary arteries. This was his second heart attack. The patient was previously diagnosed with myocardial infarction, and an immense mass was found on the left adrenal gland 3 years prior. Based on clinical and laboratory findings, a diagnosis of pheochromocytoma was confirmed. His coronary angiogram showed nonobstructed coronary arteries except for a myocardial bridge in the left anterior descending branch. This was a form of type-2 myocardial infarction. The myocardial cell lesions were caused by sudden secretion of catecholamines by the pheochromocytoma. Even more atypically, his hemoglobin level was obviously elevated at admission, but after a few days of treatment with an alpha-adrenergic receptor blocker, it dropped to normal levels without additional treatment. CONCLUSION: Pheochromocytoma may be a cause of acute myocardial infarction, heart failure, and transient erythrocytosis.

11.
Inorg Chem ; 60(4): 2829-2838, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33501829

RESUMO

Organic aromatic amines are widely used in various fields such as pharmaceuticals, pesticides, dyes, and tobacco smoke. The pollution of organic amines has become a problem that cannot be ignored, due to the extensive harmful effects on the environment and public health, which has become one of the most concerned frontier fields in the world. Identifying and microdetecting o-phenylenediamine (OPD), m-phenylenediamine (MPD), and p-phenylenediamine (PPD) using MOFs have rarely been reported. On the basis of the blue emission properties of Cu-TBDA constructed with 5,5'-((6-chloro-1,3,5-triazine-2,4-diyl)bis(azanediyl))diisophthalic acid (H4TBDA) ligand, Cu-TBDA was studied primarily to identify and detect aromatic diamine family as a multifunctional chemical sensor. Interestingly, Cu-TBDA has a very high selectivity and sensitivity to OPD and MPD with a low limit of detection (5.00 µM for OPD and 1.77 µM for MPD). Especially for OPD, Cu-TBDA has a unique switching function for it. When the concentration of OPD is less than 9.1 × 10-4 M, the fluorescence response of Cu-TBDA suspension exhibit enhanced. However, when the concentration of OPD is more than 9.1 × 10-4 M, the emission intensity displays quenching phenomenon. Therefore, Cu-TBDA as a chemical sensor not only has recognition and detection functions for organic aromatic amines but also first exhibits turn-on and -off sensing behavior toward OPD.

12.
Inorg Chem ; 59(12): 8081-8098, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32469512

RESUMO

Four new complexes, [Zn(TIBTC)(DMA)]·[NH2(CH3)2] (1), [Cd(TIBTC)(H2O)]·[NH2(CH3)2]·DMA (2), [Cd2(TIBTC)(2,2'-bipy)2(HCOO)] (3), and [Cd2(DIBTC)(2,2'-bipy)2(HCOO)] (4) (H3TIBTC = 2,4,6-triiodo-1,3,5-benzenetricarboxylic acid, H3DIBTC = 2,4-diiodo-1,3,5-benzenetricarboxylic acid, 2,2'-bipy = 2,2'-bipyridine, and DMA = dimethylacetamide), were successfully synthesized and characterized by elemental analysis, powder X-ray diffraction, infrared spectroscopy, ultraviolet-visible spectroscopy, and thermogravimetric analysis. Complexes 1 and 2 are three-dimensional supramolecular network structures, while complex 4 has a two-dimensional network structure. We preliminarily studied the fluorescence properties of the complexes and found that complexes 1-3 can detect thiamine hydrochloride, NACs, and Fe3+/Zn2+ with high sensitivity and selectivity.

13.
Inorg Chem ; 59(6): 3964-3973, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32114757

RESUMO

We successfully prepared and characterized a distinctive thorium-based MOF (metal-organic framework) Th-TTHA with thorium oxide wheel clusters under the conditions of solvothermal synthesis by utilizing thorium nitrate and semirigid triazine hexacarboxylic acid linker H6TTHA (H6TTHA = 1,3,5-triazine-2,4,6-triamine hexaacetic acid). To the best of our knowledge, Th-TTHA is the first thorium-based MOF assembled by semirigid triazine hexapod ligand H6TTHA. It is worth mentioning that Th-TTHA exhibits a novel and distinctive arrangement of structure and topology. Th-TTHA has abundant adsorption sites such as the triazine ring that is rich in nitrogen atoms, N of NH-, and carboxyl oxygen atoms without coordination with a central metal, which drove us to explore its iodine adsorption capacity. The experimental results show that Th-TTHA shows excellent adsorption capacity for iodine, and the adsorption amount in a saturated iodine cyclohexane solution can reach 528 mg/g within 24 h. This work is greatly significant for the development of new structures of thorium-based MOFs and the expansion of its functional characteristics, which is very essential for our in-depth understanding of thorium chemistry and in the management and disposal of radionuclides and application of the nuclear fuel cycle.

14.
Materials (Basel) ; 13(4)2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32059505

RESUMO

In this work, a series of modified metal-organic frameworks (MOFs) have been prepared by pre- and post-treatment with transition metal oxodiperoxo complexes (MoO(O2)2, WO(O2)2, and KVO(O2)2). The obtained materials are characterized by XRD, FTIR, SEM, TEM, inductively coupled plasma atomic emission spectrometry (ICP-AES), and X-ray photoelectron spectroscopy (XPS), as well as by N2 adsorption/desorption measurement. The characterization results show that transition metal oxodiperoxo complexes are uniformly incorporated into the MOF materials without changing the basic structures. The performance of cyclohexane oxidation on metal oxodiperoxo complex modified MOFs are evaluated. UiO-67-KVO(O2)2 shows the best performance for cyclohexane oxidation, with 78% selectivity to KA oil (KA oil refers to a cyclohexanol and cyclohexanone mixture) at 9.4% conversion. The KA selectivity is found to depend on reaction time, while hot-filtration experiments indicates that the catalytic process is heterogeneous with no leaching of metal species.

15.
Inorg Chem ; 58(23): 15898-15908, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31724839

RESUMO

A series of novel metal-organic frameworks were synthesized by using semirigid ligand 1,1',1″-(1,3,5-triazine-2,4,6-triyl)tripiperidine-4-carboxylic acid (H3TTPCA) and lead halide (Cl, Br, or I). The three complexes were characterized by elemental analysis, infrared spectroscopy, ultraviolet-visible spectroscopy, powder X-ray diffraction analysis, and thermogravimetric analysis. X-ray single-crystal diffraction analysis demonstrated that all three complexes were three-dimensional inorganic-organic framework structures with Pb-X2 (X = Cl, Br, or I). However, slight differences in the chemical environment were the focus of the coordinated halogen atoms and the different compositions of metal oxygen clusters: [Pb7(COO)12Cl2], [Pb7(COO)12Br2], and [Pb7(COO)12I2]. Because of the fluorescence of the organic ligand, the three complexes showed similar photoluminescence properties at room temperature, but the intensity of emissions decreased gradually with an increase in the atomic radius of coordinated halogen atoms. Interestingly, in the fluorescence response tests, complexes 1 and 2 displayed an optical signal of fluorescence "turn-on" while complex 3 showed an optical signal of fluorescence "turn-off". Here we aim to provide a possible mechanism to explain these unique and contradictory luminescence results.

16.
Inorg Chem ; 57(20): 12850-12859, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30270622

RESUMO

Under hydrothermal conditions, we have successfully synthesized six isostructural lanthanide coordination polymers, [LnL1.5(H2O)2]·1.75H2O (1-6; Ln = Eu, La, Pr, Nd, Sm, Gd), by the reaction of 5-methyl-1-(4-carboxylphenyl)-1 H-1,2,3-triazole-4-carboxylic acid (H2L) and Ln(NO3)3·6H2O. Structural analysis shows that polymers 1-6 show novel three-dimensional supramolecular network structures. The luminescent properties for polymer 1 have been investigated at room temperature. The results have shown that polymer 1 can be used as a chemical sensor for multifunctional testing such as UO22+, Fe3+ ion detection, and small organic molecule detection because of its strong fluorescence properties. In particular, polymer 1 exhibits extremely high selectivity and sensitivity for the detection of Fe3+ ions. In addition, white-light emission is achieved through a reasonable tuning proportion by mixing Gd3+ and Eu3+.

18.
Spectrochim Acta A Mol Biomol Spectrosc ; 150: 308-15, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26056981

RESUMO

A series of 3d-4f heterobinuclear complexes were constructed by employing the 2,2'-bipy (2,2'-bipy=2,2'-bipyridine) ligand and corresponding metal ions (M(II)/Ln(III), M=Co(II), Cu(II) and Zn(II); Ln(III)=Nd(III), Sm(III), Eu(III) and Tb(III)). Elemental analyses, IR, UV-vis-NIR spectra, PXRD and single crystal X-ray diffraction analysis reveal that complexes 1-4, 5-8, and 9-12 are isomorphous, respectively. The zero-dimensional structures are further connected to 2D or 3D supramolecular network structures via extensive intermolecular hydrogen bonds. Luminescence studies for the heterobinuclear complexes containing Sm(III), Eu(III) and Tb(III) reveal that the chromophoric composed of Zn(II)/L may efficiently sensitize the luminescence of the rare earth cations which acts as an antenna, whereas the existence of Cu(II) leads to the quenching of the luminescence of Ln(III) ions.

19.
J Nanosci Nanotechnol ; 15(11): 9192-6, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26726666

RESUMO

Considerable efforts have been made to shift the phase transition temperature of metal-doped vanadium dioxide (VO2) films nearer the ambient temperature while maintain the excellent thermochromic properties simultaneously. Here, we describe a facile and economic solution-based method to fabricate W-doped VO2 (V(1-x)W(x)O2) thin films with excellent thermochromic properties for the application of smart windows. The substitutional doping of tungsten atoms notably reduces the phase transition temperature to the ambient temperature and retains the excellent thermochromic property. Furthermore, Ag nanowires (NWs) are employed as capping layers to effectively decrease the thermal emissivity from 0.833 to 0.603, while the original near infrared region (NIR) modulation ability is not severely affected. Besides, the Ag NWs layers further depress the phase transition temperature as well as the hysteresis loop width, which is important to the fenestration application. These solution-grown Ag NWs/V(1-x)W(x)O2 thin films exhibit excellent solar modulation ability, narrowed hysteresis loop width as well as low thermal emissivity, which provide a promising perspective into the practical application of VO2-based smart windows.

20.
Zhonghua Yi Xue Za Zhi ; 93(11): 827-31, 2013 Mar 19.
Artigo em Chinês | MEDLINE | ID: mdl-23859388

RESUMO

OBJECTIVE: To explore the prevalence and risk factors of atherosclerotic renal artery stenosis (ARAS) in patients undergoing coronary angiography. METHODS: A total of 2506 patients with suspected and known coronary heart disease (CAD) at our hospital underwent simultaneous coronary and renal angiography. Renal artery stenosis was defined as at least one of renal artery stenosis ≥ 50% narrowing of luminal diameter. The prevalence of ARAS was summarized from the results of angiography. And single- and multi-variable logistic regression analysis was used to assess the relationship between clinical characteristics and ARAS. RESULTS: Among them, there were 1479 males and 1027 females with a mean age of 62.7 ± 11.4 years. ARAS was detected in 409 patients (16.3%), including 214 (8.5%) with significant stenosis (≥ 75%); Bilateral ARAS was detected in 98 patients (3.9%), including 27 (1.1%) with significant stenosis (≥ 75%). Left and right ARAS were detected in 162 patients (6.5%) and 148 patients (5.9%) respectively, including 84 patients (3.4%) with significant stenosis (≥ 75%) in left ARAS and 72 patients (2.9%) in right ARAS. Univariate analysis indicated that age, females, diabetes, hypertension, stroke, peripheral artery disease, coronary heart disease, renal insufficiency, dyslipidemia and hyperuricemia were the predictor for ARAS (P < 0.05 or 0.01). Multivariate regression analysis demonstrated that age ≥ 65 years (P = 0.025, OR = 1.358), females (P < 0.01, OR = 1.678), hypertension (P < 0.01, OR = 1.650), peripheral artery disease (P < 0.01, OR = 14.678), renal insufficiency (P < 0.01, OR = 1.835), coronary heart disease including 3-vessel (P < 0.01, OR = 1.746) and left main coronary (P < 0.01, OR = 3.416)disease were independent risk factors for ARAS. CONCLUSION: Renal angiography should be routinely performed in female patients aged ≥ 65 years with hypertension, peripheral artery disease, elevated creatinine and coronary heart disease, especially for 3-vessel and left main coronary disease to identify ARAS in time.


Assuntos
Arteriosclerose/complicações , Obstrução da Artéria Renal/etiologia , Idoso , Arteriosclerose/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Obstrução da Artéria Renal/epidemiologia , Fatores de Risco
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