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1.
Transpl Immunol ; 84: 102020, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38452982

RESUMEN

OBJECTIVE: Innate immunity plays a vital role in xenotransplantation. A CD47 molecule, binding to the SIRPα expressed on monocyte/macrophage cells, can suppress cytotoxicity. Particularly, the SIRPα contains ITIM, which delivers a negative signal. Our previous study demonstrated that the binding between CL-P1 and surfactant protein-D hybrid (CL-SP-D) with SIRPα regulates macrophages' phagocytic activity. In this study, we examined the effects of human CD47 and CL-SP-D expression on the inhibition of xenograft rejection by neutrophils in swine endothelial cells (SECs). METHODS: We first examined SIRPα expression on HL-60 cells, a neutrophil-like cell line, and neutrophils isolated from peripheral blood. CD47-expressing SECs or CL-SP-D-expressing SECs were generated through plasmid transfection. Subsequently, these SECs were co-cultured with HL-60 cells or neutrophils. After co-culture, the degree of cytotoxicity was calculated using the WST-8 assay. The suppressive function of CL-SP-D on neutrophils was subsequently examined, and the results were compared with those of CD47 using naïve SECs as controls. Additionally, we assessed ROS production and neutrophil NETosis. RESULTS: In initial experiments, the expression of SIRPα on HL-60 and neutrophils was confirmed. Exposure to CL-SP-D significantly suppressed the cytotoxicity in HL-60 (p = 0.0038) and neutrophils (p = 0.00003). Furthermore, engagement with CD47 showed a suppressive effect on neutrophils obtained from peripheral blood (p = 0.0236) but not on HL-60 (p = 0.4244). The results of the ROS assays also indicated a significant downregulation of SEC by CD47 (p = 0.0077) or CL-SP-D (p = 0.0018). Additionally, the suppression of NETosis was confirmed (p = 0.0125) in neutrophils co-cultured with S/CL-SP-D. CONCLUSION: These results indicate that CL-SP-D is highly effective on neutrophils in xenogeneic rejection. Furthermore, CL-SP-D was more effective than CD47 at inhibiting neutrophil-mediated xenograft rejection.

2.
RSC Adv ; 13(40): 28104-28111, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37746343

RESUMEN

Films that exhibit different metallic luster on the front and back, called Janus metallic films, have broad applications ranging from design materials to optical devices. However, the fabrication of these films is often a complicated process involving multiple metal deposition steps, thermal annealing, and calcination. Herein, we report the simple preparation of a Janus metallic film by electroless deposition of silver on a poly(dopamine acrylamide) (pDOPAm) thin film. pDOPAm was successfully synthesized via the controlled reversible addition-fragmentation chain transfer polymerization of dopamine acrylamide without a protective group using dimethylformamide as the solvent. The synthesized pDOPAm was spin-coated onto a solid substrate, which was then immersed in an aqueous AgNO3 solution to achieve the electroless deposition of silver. Our preparation method will considerably simplify the fabrication of Janus metallic films, enabling their widespread application as decorative or authentication materials.

3.
Asian J Endosc Surg ; 16(4): 809-813, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37394285

RESUMEN

INTRODUCTION: The therapeutic strategy for superficial nonampullary duodenal epithelial tumors remains controversial. We developed a novel surgical technique for superficial nonampullary duodenal epithelial tumors. We report the initial two cases managed with this method. MATERIALS AND SURGICAL TECHNIQUE: We endoscopically confirmed the tumor location and circumferentially incised the seromuscular layer of the duodenum along it. After circumferential seromyotomy, the submucosal layer was expanded by endoscopic insufflation, and the target lesion was sufficiently lifted. The submucosal layer, including the target lesion, was stapled and resected after confirming the absence of problems with endoscopic passage. The seromuscular layer was continuously sutured to bury and reinforce the stapler line. Single-incision laparoscopic surgery was performed in one case. The resected specimens measured 52 × 32 mm and 50 × 26 mm with negative surgical margins. Both patients were discharged without complications and demonstrated no evidence of stenosis. DISCUSSION: Compared with previously reported procedures, this method of partial duodenectomy with seromyotomy for superficial nonampullary duodenal epithelial tumors is promising, simple, and safe.


Asunto(s)
Carcinoma , Procedimientos Quirúrgicos del Sistema Digestivo , Neoplasias Duodenales , Laparoscopía , Humanos , Duodeno/cirugía , Neoplasias Duodenales/cirugía , Neoplasias Duodenales/patología , Laparoscopía/métodos , Carcinoma/patología
4.
Soft Matter ; 19(17): 3058-3068, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37017407

RESUMEN

This study demonstrates that a simple statistical copolymer can form self-assembled lamellae, whose structures depend on both the comonomer composition and the annealing temperature. Statistical copolymers of octadecyl acrylamide and hydroxyethyl acrylamide [p(ODA/HEAm)] were prepared via free-radical copolymerization, and their thermal properties were studied by differential scanning calorimetry. Thin films of p(ODA/HEAm) were prepared via spin-coating, and their structures were analyzed using X-ray diffraction. It was found that copolymers with HEAm contents between 28 and 50% formed self-assembled lamellae upon annealing at a temperature ∼10 °C above the glass-transition temperature. The self-assembled form was found to possess a "side-chain-mixed" lamellar structure, in which the ODA and HEAm side chains are oriented perpendicular to the lamellar plane composed of the polymer main chain. Interestingly, a copolymer with a HEAm content between 36 and 50% transformed from the side-chain-mixed lamellar structure to generate a "side-chain-segregated" lamellar structure upon annealing at a significantly higher temperature (∼50 °C above Tg). In this structure, the ODA and HEAm side chains were found to be oriented in opposite directions but perpendicular to the lamellar plane. The packing of the side chains in the lamellar structures was studied using Fourier-transform infrared spectroscopy. It was concluded that the structures of the self-assembled lamellae are determined by the strain forces generated during self-assembly, and by the segregation forces existing between the comonomers.

5.
Ann Med Surg (Lond) ; 85(2): 266-270, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36845766

RESUMEN

Diffusely infiltrative squamous cell carcinoma of the esophagus is rare and difficult to diagnose. Case presentation: The patient was a 75-year-old woman whose chief complaints were dysphagia and upper abdominal pain. Esophagogastroduodenoscopy and biopsy revealed squamous cell carcinoma at the abdominal esophagus. After neoadjuvant chemotherapy, esophagogastroduodenoscopy showed diffuse thickening and poor distensibility of the stomach wall. We suspected scirrhous gastric cancer and performed multiple biopsies, which revealed no evidence of malignancy. We then performed staging laparoscopy. There were no apparent changes in the serous membrane of the stomach, but peritoneal lavage cytology revealed squamous cell carcinoma. Thus, we made a diagnosis of squamous cell carcinoma of the esophagus with diffuse invasion of the stomach. Intraoperative pathological diagnosis revealed that there was greater diffuse submucosal invasion of the oral esophagus than we expected, and we had to resect the esophagus at the level of the middle thoracic esophagus. Despite multidisciplinary treatment (surgery, chemotherapy, and radiotherapy), the patient died 20 months after the initial diagnosis. Clinical discussion: In this case, although biopsy did not lead to a diagnosis, peritoneal lavage cytology led to the correct diagnosis. Moreover, it was impossible to preoperatively predict the exact extent of the expansion because of diffuse submucosal invasion. Conclusion: When diffusely infiltrative squamous cell carcinoma of the esophagus is suspected, peritoneal lavage cytology may be useful for confirming the diagnosis; however, it should be assumed that accurate preoperative evaluation of the range of diffusely infiltrative squamous cell carcinoma is difficult.

6.
Sci Technol Adv Mater ; 23(1): 783-795, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36452272

RESUMEN

Low-density films of single-walled carbon nanotubes (SWNTs) can be used as a semi-transparent top electrode for all-solution-processed film devices; however, their semiconductor characteristics vary depending on the experimental factors in their dispersion into solvents, and the sublayers are damaged as a result of solvent incompatibility. In this study, we report a solvent-compatible filter-transfer method for SWNT films stacked with silver nanowires (AgNWs), and evaluate the semiconductor characteristics through the p/n heterojunction with a Si wafer (SWNT/Si). AgNWs and SWNTs were successively filtered through their aqueous dispersion solutions using a membrane filter. The stacked semi-transparent films (AgNW/SWNT films with controlled densities) were successfully transferred onto glass plates and Si wafers. The transmittance at 550 nm revealed a window between 60% and 80% with a narrow sheet resistance range between 11 and 23 Ω â–¡-1. The power conversion efficiency (PCE) of SWNT/Si was improved to 11.2% in a junction area of 0.031 cm2 through the use of spin-coated Nafion resins; however, the accumulated resistance of SWNTs drastically reduced the PCE to 2% as the area increased to ≥0.5 cm2. AgNWs maintained the PCE within a range of 10.7% to 8.6% for an area ranging from 0.031 cm2 to 1.13 cm2. All of the photovoltaic parameters were dependent on the junction areas, suggesting that AgNWs function as an effective current-collector layer on the semiconductor layer of SWNTs without direct contact of AgNWs with the Si surface. In addition, we report a solvent-compatible experiment for transferring AgNW/SWNT films onto a solvent-sensitive perovskite material (CH3NH3PbI3).

7.
Pediatr Surg Int ; 38(12): 1815-1820, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36109363

RESUMEN

PURPOSE: To determine an early diagnostic indicator of biliary atresia (BA), we focused on morphological left-right differences of BA livers. METHODS: Of 74 infants with suspected BA at our hospital in the last 12 years, 25 met the conditions for investigation: 15 infants with BA (BA group) and 10 with other pathologies (non-BA group). CT volumetry of the liver in each patient was performed using a 3D image analysis system. Patient characteristics, blood data, and proportion of the left lateral segment to the total liver volume (LLS ratio) were compared between the two groups. RESULTS: Among the patient characteristics and liver function tests, only γ-glutamyl transpeptidase (GGT) were significantly higher in the BA group (p < 0.001). The LLS ratio was 0.321 (0.227-0.382) in the BA group and 0.243 (0.193-0.289) in the non-BA group (p = 0.01). The summary cut-off, area under the curve, sensitivity, and specificity were 0.322, 0.813, 53.3, and 100% for the LLS ratio and 94.26, 0.95, 86.7, and 100% for the GGT × LLS ratio, respectively. CONCLUSIONS: The LLS ratio is highly specific and may be an early diagnostic predictor of BA. Moreover, this segmental LLS enlargement may be associated with the etiology of BA.


Asunto(s)
Atresia Biliar , Lactante , Humanos , Atresia Biliar/diagnóstico por imagen , Atresia Biliar/complicaciones , Hígado/diagnóstico por imagen , Hígado/cirugía , gamma-Glutamiltransferasa , Pruebas de Función Hepática , Portoenterostomía Hepática
8.
ACS Omega ; 7(19): 16778-16784, 2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35615387

RESUMEN

In this study, we have prepared thermally and chemically stable lamellar polymer films via humid annealing. The amphiphilic polymer poly(N-dodecyl acrylamide-stat-3-(trimethoxysilyl)propyl acrylate) [p(DDA/TMSPA)] forms a self-assembled lamellar structure via annealing at 60 °C under 98% relative humidity (humid annealing) due to nanophase separation between the hydrophobic dodecyl side and main chains with the amide groups that contain adsorbed water. Moreover, a self-cross-linking reaction of TMSPA proceeds during the humid annealing. As a result, the lamellar films maintain their structure even when annealed above their glass-transition temperature. On the other hand, the films swell when immersed in toluene. The highly ordered lamellar structure collapses due to the swelling but can be re-established by subsequent humid annealing. A multilayer freestanding film can be exfoliated via sonication in toluene. The exfoliated multilayer films initially form a dome-shaped structure, which is converted to a plate-shaped structure upon humid annealing. In their entirety, these results reveal that the molecular-scale movement associated with the formation of the lamellar structure induces a macroscopic structural change. Consequently, p(DDA/TMSPA) can be considered as a new stimulus-responsive polymer.

10.
Sci Rep ; 11(1): 23196, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34853366

RESUMEN

Here, we aimed to evaluate the clinical performance of a novel automated immunoassay HISCL SARS-CoV-2 Antigen assay kit designed to detect the nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This kit comprises automated chemiluminescence detection systems. Western blot analysis confirmed that anti-SARS-CoV antibodies detected SARS-CoV-2N proteins. The best cut-off index was determined, and clinical performance was tested using 115 serum samples obtained from 46 patients with coronavirus disease 2019 (COVID-19) and 69 individuals who tested negative for COVID-19 through reverse transcription quantitative polymerase chain reaction (RT-qPCR). The HISCL Antigen assay kit showed a sensitivity of 95.4% and 16.6% in samples with copy numbers > 100 and < 99, respectively. The kit did not cross-react with human coronaviruses causing seasonal common cold and influenza, and none of the 69 individuals without COVID-19 were diagnosed with positive results. Importantly, 81.8% of the samples with low virus load (< 50 copy numbers) were diagnosed as negative. Thus, using HISCL antigen assay kits may reduce overdiagnosis compared with RT-qPCR tests. The rapid and high-throughput HISCL SARS-CoV-2 Antigen assay kit developed here proved suitable for screening infectious COVID-19 and may help control the pandemic.


Asunto(s)
Prueba Serológica para COVID-19/métodos , COVID-19/diagnóstico , Proteínas de la Nucleocápside de Coronavirus/inmunología , Inmunoensayo/métodos , SARS-CoV-2/inmunología , Western Blotting , COVID-19/inmunología , COVID-19/virología , Reacciones Cruzadas , Humanos , Fosfoproteínas/inmunología
11.
Biochem Biophys Res Commun ; 576: 22-26, 2021 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-34478915

RESUMEN

Blood based ß-amyloid (Aß) assays that can predict amyloid positivity in the brain are in high demand. Current studies that utilize immunoprecipitation mass spectrometry assay (IP-MS), which has high specificity for measuring analytes, have revealed that precise plasma Aß assays have the potential to detect amyloid positivity in the brain. In this study, we developed plasma Aß40 and Aß42 immunoassays using a fully automated immunoassay platform that is used in routine clinical practice. Our assays showed high sensitivity (limit of quantification: 2.46 pg/mL [Aß40] and 0.16 pg/mL [Aß42]) and high reproducibility within-run (coefficients of variation [CVs]: <3.7% [Aß40] and <2.0% [Aß42]) and within-laboratory (CVs: <4.6% [Aß40] and <5.3% [Aß42]). The interference from plasma components was less than 10%, and the cross-reactivity with various lengths of Aß peptides was less than 0.5%. In addition, we found a significant correlation between the IP-MS method and our immunoassay (correlation coefficients of Pearson's r: 0.91 [Aß40] and 0.82 [Aß42]). Our new method to quantify plasma Aß40 and Aß42 provides clinicians and patients with a way to continuously monitor disease progression.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Péptidos beta-Amiloides/sangre , Técnicas para Inmunoenzimas/métodos , Inmunoprecipitación/métodos , Espectrometría de Masas/métodos , Fragmentos de Péptidos/sangre , Plasma/metabolismo , Enfermedad de Alzheimer/sangre , Biomarcadores/sangre , Humanos , Luminiscencia , Reproducibilidad de los Resultados
12.
Langmuir ; 37(17): 5393-5398, 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-33885305

RESUMEN

Self-assembled lamellar films of poly(N-dodecyl acrylamide-stat-vinyl phosphonic acid) [p(DDA/VPA)] were formed via the segregation between the hydrophilic main chain and VPA and dodecyl side chains. p(DDA/VPA) copolymers were synthesized by free-radical copolymerization of DDA and VPA with VPA molar concentrations of 19% [p(DDA/VPA19)] and 64% [p(DDA/VPA64)]. Both copolymers exhibited a glass-transition temperature (Tg) and melting temperature for p(DDA/VPA19), but no crystalline or liquid-crystalline phase-transition temperatures, which suggests that both copolymers are amorphous. Thin films of the copolymers were prepared by spin coating, and the structure of the films was studied by X-ray diffraction (XRD) measurements. The as-cast films of the copolymers showed broad diffraction patterns, which suggested the formation of alkyl nanodomains similar to that observed in the pDDA homopolymers. On the other hand, the XRD patterns for both copolymer films showed a sharp Bragg diffraction in the low-q region after annealing at 60 °C. Furthermore, the p(DDA/VPA19) film showed first- and second-order Bragg diffractions with a ratio of 1:2. These XRD patterns suggest that the copolymer films form an ordered lamellar structure. We concluded that the main chain became more hydrophilic by the introduction of VPA, resulting in an increased segregation force relative to the hydrophobic dodecyl side chains, which induces the formation of lamellae. Moreover, doping a p(DDA/VPA64) film with imidazole increased the ordering and uniformity of the lamellar structures due to the increased segregation force by the formation of ion pairs in the hydrophilic comonomer. In their entirety, the results show that statistical copolymerization can be used as a new method to create self-assembled structures.

13.
Materials (Basel) ; 14(5)2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33806446

RESUMEN

Conjugated donor-acceptor molecules with intramolecular charge transfer absorption are employed for single-component organic solar cells. Among the five types of donor-acceptor molecules, the strong push-pull structure of DTDCPB resulted in solar cells with high JSC, an internal quantum efficiency exceeding 20%, and high VOC exceeding 1 V with little photon energy loss around 0.7 eV. The exciton binding energy (EBE), which is a key factor in enhancing the photocurrent in the single-component device, was determined by quantum chemical calculation. The relationship between the photoexcited state and the device performance suggests that the strong internal charge transfer is effective for reducing the EBE. Furthermore, molecular packing in the film is shown to influence photogeneration in the film bulk.

14.
Surg Case Rep ; 6(1): 270, 2020 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-33074371

RESUMEN

BACKGROUND: Delayed arterial hemorrhage after pancreaticoduodenectomy is a life-threatening complication. There are no reports about infected aneurysms of the superior mesenteric artery after pancreaticoduodenectomy without clinically relevant pancreatic fistula. CASE PRESENTATION: A 78-year-old woman with borderline resectable pancreatic ductal adenocarcinoma involving the superior mesenteric arterial nerve plexus underwent pancreaticoduodenectomy with en bloc resection of the superior mesenteric vein and the superior mesenteric arterial nerve plexus after neoadjuvant chemotherapy. On postoperative day 14, she had bacteremia and sudden fever with chills. During the postoperative course, macroscopic abscesses or distinct infectious signs, including pancreatic fistula or bile fistula, were not present, but pylephlebitis was observed. After the antimicrobial treatment course, the patient was discharged. After 17 days, she was hospitalized for melena. Contrast-enhanced computed tomography showed a ruptured aneurysm of the superior mesenteric artery into the small intestine without a major intraabdominal abscess. E. coli was isolated from blood cultures. The patient was diagnosed with a ruptured infected aneurysm of the superior mesenteric artery. She was treated successfully with a covered stent by the cardiology team. There was no recurrence of bleeding at the 4-month follow-up, and the stent was patent in all subsequent computed tomography scans. CONCLUSIONS: Endovascular repair using a covered stent was effective in palliating acute bleeding from an infected aneurysm of the superior mesenteric artery.

15.
Int J Surg Case Rep ; 76: 121-124, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33032041

RESUMEN

INTRODUCTION: Diaphragm disease is rare and caused by intestinal obstruction due to nonsteroidal anti-inflammatory drugs (NSAIDs). Given the availability of video capsule endoscopy (VCE) and balloon enteroscopy (BE) this disease will be diagnosed more often. PRESENTATION OF CASE: A 73-year-old man was presented to our hospital for persistent nausea and vomiting. Abdominal ultrasound and computed tomography revealed small-bowel thickening, stricture in the terminal ileum, and dilation of the proximal small intestine. Differential diagnosis included ileal lymphoma and multiple ileal adenocarcinomas, and a diagnostic laparoscopy was performed. Twenty-centimeter of ileum was resected by primary ileo-ileal anastomosis. On pathological examination, fibrosis of the submucosa was identified, and erosions and numerous inflammatory cells reaching the submucosa were also identified from the specimen. DISCUSSION: The preoperative diagnosis of diaphragm disease is sometimes challenging due to its uncharacteristic symptoms; moreover, radiological findings are usually indefinite and distinctive. Currently, the main treatment for diaphragm disease is surgery. CONCLUSION: We have documented a case of intestinal obstruction by NSAIDs. However, it is desirable to determine the course of treatment based on small bowel endoscopic dilatation cases in the future.

16.
Langmuir ; 36(40): 12023-12029, 2020 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-32931290

RESUMEN

Wettability control of porous materials is significant in lateral flow immunoassay, microfluidic systems, microdroplet manipulation, and so on. In this report, formation of metal oxide layers on self-organized polymer honeycomb films to control surface wettability by simple sol-gel coating and UV-O3 treatment was demonstrated. By the combination of bottom-up and top-down processes, silica thin layers can be formed by retaining their original three-dimensional honeycomb structures. Furthermore, photopatterning of metal oxides on honeycomb films can be achieved by UV irradiation through photomasks. Site-selective wettability control of honeycomb films was realized by patterning silica layers on the surface of the film.

17.
Phys Chem Chem Phys ; 22(38): 21672-21677, 2020 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-32914801

RESUMEN

Periodic patterns are ubiquitous in nature and spontaneously form on molecular to cosmic scales by the interplay between reaction and diffusion. Understanding how these patterns form is important to understand the construction rules of nature and apply them in the synthesis of functional artificial materials. This work clarifies how radical (R˙) species affect pattern formation in periodic precipitated and depleted zones during a polymerization process in an agarose gel. When a monomer (Mon) solution was poured on top of the gel doped with an initiator (In) in a test tube, periodic and continuous precipitation occurred near and far away from the solution/gel interface, respectively. In contrast, a system without In exhibited only a continuous band of precipitates beyond a depleted zone without precipitates at a certain distance from the interface. In the depleted region, an inhibitor (Q) added to the solution limited the polymerization triggered by R˙ formed thermally from Mon. With the addition of enough In to overcome the quenching effect of Q, periodic bands appeared near the solution/gel interface. These results suggest the involvement of two independent polymerization processes: (i) polymerization triggered by R˙ formed from In, which is the dominant process up to 100 h and yields periodic structures near the interface. After 100 h, the dominant process is the polymerization triggered by R˙ generated thermally from Mon, which yields a continuous precipitation zone. These two R˙ species compete and generate periodic bands near the interface (<100 h) and a continuous band far away from the interface (>100 h).

18.
Langmuir ; 36(35): 10371-10378, 2020 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-32841566

RESUMEN

This paper proposes a method of fabricating low-dimensional TiO2 nanofilms at room temperature under ambient pressure conditions. The titanium-containing polymer complex Ti-p(DDA/acac) was synthesized by reacting an amphiphilic copolymer (p(DDA/acac)) with a titanium complex. Its ultrathin films were prepared using the Langmuir-Blodgett (LB) technique. The monolayer was found to be free from hydrolysis and cross-linking side reactions, even at the air-water interface. The transferred LB films (nanosheets) were oxidized by ultraviolet irradiation at room temperature. The photo-oxidized material has an amorphous and porous structure with subnanometer-scale controllability (0.18 nm per layer). Photocatalytic performance was demonstrated by converting multilayered LB films of Ti-(DDA/acac) and the silicon-containing polymer p(DDA/SQ) into ultrathin hetero-multilayers of TiO2 and SiO2 under UV-O3 treatment. The scalability affords a uniform photopattern formation of photo-oxidized TiO2 films over several hundreds of micrometers.

19.
Nanoscale ; 12(11): 6263-6270, 2020 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-32048703

RESUMEN

The effect of ultrasonic irradiation on the optical properties of single-walled carbon nanotubes (SWNTs) was investigated. Upon sonication in D2O in the presence of sodium dodecylbenzene sulfonate (SDBS) under air, red-shifted photoluminescence (PL) peaks at ∼1043 and ∼1118 nm were observed from the aqueous suspensions of (6,4) and (6,5)SWNTs, accompanied by a decrease in the intensity of the intrinsic PL peaks. Upon sonication with SDBS under an Ar atmosphere, the rate of spectral change increased with the sonication time and new PL peaks emerged at 1043, 1118, and 1221 nm. Meanwhile, upon the addition of 1-butanol, the PL peaks emerged only at 1043 nm and 1118 nm, while the emergence of the peak at 1221 nm was inhibited. On the other hand, a suspension with highly dispersed SWNTs was obtained upon sonication in the presence of sodium cholate without any change in the intrinsic optical properties of SWNTs. These experimental results reveal that the PL characteristics of SWNTs can be controlled by controlling the sonication conditions such as the type of surfactant used, the concentration of SWNTs, reaction environment, and the presence of an inhibitor such as 1-butanol.

20.
Turk J Chem ; 44(2): 296-308, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33488158

RESUMEN

Silsesquioxane-based transition-metal complexes have come to the forefront due to the ability of silsesquioxane to control nanostructures and properties. However, some difficulties in complete complexation and purification limit the widespread use of transition-metal-based supramolecular coordination complexes comprising silsesquioxane. Herein, 2 different approaches have been proposed for the synthesis of metallo-supramolecular materials on the basis of ruthenium(II)-terpyridine functional double-layer silsesquioxane (DDSQ) (Tpy/Ru-DDSQ) (Routes 1 and 2). In Route 1, complexation was followed by functionalization of DDSQ with the ligand, whereas in Route 2, complexation was performed before the ligand was inserted into the DDSQ. Tpy/Ru-DDSQ obtained from both approaches was characterized by 1H NMR, X-ray photoelectron spectrometer, and FTIR and found in the same structure. Both methods were fully discussed and their merits were explored. The complexation yield of the routes was similar. However, the results based on NMR and UV-Vis spectroscopy demonstrated that the incorporation rate of DDSQ into the complex was quite high in Route 2. As far as is known, this is the first study based on the effects of complexing Tpy ligands before/after binding to the target compound, particularly to silsesquioxane-based materials.

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