26 research outputs found
Subtypes of renal cell carcinoma: MRI and pathological features
Renal cell carcinoma (RCC) is the most common malignant tumor involving the kidney. Determining the subtypes of renal cell carcinoma is among the major goals of preoperative radiological work-up. Among all modalities, magnetic resonance imaging (MRI) has several advantages, such as inherent soft tissue contrast, detection of lipid and blood products, and excellent sensitivity to detect small amounts of intravenous contrast, which facilitate the discrimination of subtypes of RCC. In this article, we review MRI and pathological features used for determining the main histologic subtypes of RCC, including clear cell, papillary, collecting duct, chromophobe, multilocular cystic, and unclassified RCC
T1186 Magnetic Resonance Enterography Impacts Medical and Surgical Decisions in Obstructive Crohn's Disease
Spontaneous rupture of the inferior vena cava (IVC) in the setting of IVC filter thrombosis: case report
Hierarchical Porous TiO<sub>2</sub> Embedded Unsymmetrical ZincâPhthalocyanine Sensitizer for Visible-Light-Induced Photocatalytic H<sub>2</sub> Production
In
this study, a novel visible-light-driven photocatalyst was designed
based on unsymmetrical zincâphthalocyanine photosensitizer
on hierarchical porous TiO<sub>2</sub> (HPT) semiconductor. The HPT
material has been prepared by a simple self-formation route. The present
work successfully uses zinc phthalocyanine with spectral response
extended to 700 nm triggers light harvesting center and HPT semiconductors
for high photocatalytic H<sub>2</sub> production. This novel unsymmetrical
zincâphthalocyanine (PCH001) containing three <i>tert</i>-butyl and two carboxylic acid groups that act as âpushâ
and âpullâ electron transfer properties from the excited
dye to the TiO<sub>2</sub> conduction band. The carboxylic group in
the sensitizer serves as an anchoring group on to the surface of TiO<sub>2</sub> and to provide intimate electronic coupling between its excited-state
wave function and the conduction-band manifold of the semiconductor.
The excellent photophysical properties was governed further by choosing
three <i>tert</i>-butyl groups which tuned the LUMO level
of the sensitizer that provides directionality in the excited state
in addition to low aggregation and high solubility. The Zn-PCH@TiO<sub>2</sub> composites exhibited promising activity and enhanced stability
a photocatalytic system for visible-light-induced hydrogen production
from water. The photocatalyst (HPT-0.25) shows H<sub>2</sub> production
yield 2260 Îźmol and high turnover number (TON 18080) under visible/near
IR light irradiation. Moreover, HPT-0.25 photocatalyst shows a broad
visible/NIR light responsive range (400â800 nm) with high apparent
quantum yields (AQY) of 7.15, 2.70, 11.57, 3.90, and 0.50% under Îť
= 420, 550, 690, 730, and 800 nm monochromatic light irradiation,
respectively. The present work gives a new advance toward efficient
solar energy conversion with promising visible/near IR light-driven
photocatalytic activity
High-efficiency organic solar cells prepared using a halogen-free solution process
Although the power conversion efficiency (PCE) of organic photovoltaic (OPV) devices has recently improved to more than 16%, halogenated solution processes are typically employed to obtain optimal performance. However, halogenated processing is harmful to health and the environment, which can be a significant obstacle to commercialization. Therefore, development of active materials processable under halogen-free conditions is of great importance in this field. In this study, a 16.04% OPV device, processed under halogen-free conditions, is developed by employing a new active-blend system, PBDTTPD-HT:BTP-2F-BO. It is highly soluble in halogen-free solvents, forming a preferential bulk-heterojunction morphology. The PBDTTPD-HT:BTP-2F-BO device achieves a PCE comparable with current state-of-the-art devices based on PBDB-TF:BTP-4F (also known as PM6:Y6) using a conventional halogenated process (16.40% versus 16.33%). Furthermore, it demonstrates a significantly higher PCE than the PBDB-TF:BTP-4F device with a halogen-free process (16.04% versus 9.70%)
Near-infrared absorbing unsymmetrical Zn(II) phthalocyanine for dye-sensitized solar cells
Unsymmetrical Zn phthalocyanine consisting of six S-aryl groups at Îą-positions and a carboxy anchoring group at β-position has been designed and synthesized for dye-sensitized solar cells (DSCs) applications. The unsymmetrical phthalocyanine has been characterized by elemental, MALDI-MS, IR, 1H NMR, UVâVis, fluorescence (steady-state & lifetime) and electrochemical (including spectroelectrochemical) methods. The Q-band absorption maxima of the unsymmetrical phthalocyanine was red-shifted due to the presence of S-aryl groups, which destabilizes the HOMO level consistent with electrochemical and in situ spectroelectrochemical studies. The redox processes are assigned to the macrocyclic ring-based electron transfer processes, the LUMO of the unsymmetrical phthalocyanines lies above the TiO2 conduction band, and the HOMO is well below the potential of the Iâ/I3â redox electrolyte. The experimental results are supported by DFT/TD-DFT studies. The new unsymmetrical phthalocyanines was tested in DSCs using Iâ/I3â redox electrolyte system
DâĎâA system based on zinc porphyrin dyes for dye-sensitized solar cells: Combined experimental and DFTâTDDFT study
A series of four new porphyrin-furan dyads were designed and synthesized by having anchoring group either at meso-phenyl or pyrrole-β position of a zinc porphyrin based on donorâĎâacceptor (DâĎâA) approach. The porphyrin macrocycle acts as donor, furan hetero cycle acts as Ď-spacer and either cyanoacetic acid or malonic acid group acts as acceptor. These dyads were fully characterized by UVâVisible, 1H NMR, MALDI-MS and fluorescence spectroscopies and cyclic voltammetry. Both of the observed and TD-DFT simulated UVâVis spectra has strong correlation which validate and confirm the synthesized dyads and theoretical method for this type of compounds. Both soret and Q-bands are red shifted in the case of pyrrole-β substituted dyads. The redox potentials of all four dyads are not altered in comparison with their individual constituents. The dyads were tested in dye sensitized solar cells and found pyrrole-β substituted zinc porphyrins are showing better performance in comparison with the corresponding meso-phenyl dyads. Optical band gap, Natural bonding, and Molecular bonding orbital (HOMOâLUMO) analysis are in favour of pyrrole-β substituted zinc porphyrins contrast to meso-phenyl dyads
DâĎâA system based on zinc porphyrin dyes for dye-sensitized solar cells: Combined experimental and DFTâTDDFT study
A series of four new porphyrin-furan dyads were designed and synthesized by having anchoring group either at meso-phenyl or pyrrole-β position of a zinc porphyrin based on donorâĎâacceptor (DâĎâA) approach. The porphyrin macrocycle acts as donor, furan hetero cycle acts as Ď-spacer and either cyanoacetic acid or malonic acid group acts as acceptor. These dyads were fully characterized by UVâVisible, 1H NMR, MALDI-MS and fluorescence spectroscopies and cyclic voltammetry. Both of the observed and TD-DFT simulated UVâVis spectra has strong correlation which validate and confirm the synthesized dyads and theoretical method for this type of compounds. Both soret and Q-bands are red shifted in the case of pyrrole-β substituted dyads. The redox potentials of all four dyads are not altered in comparison with their individual constituents. The dyads were tested in dye sensitized solar cells and found pyrrole-β substituted zinc porphyrins are showing better performance in comparison with the corresponding meso-phenyl dyads. Optical band gap, Natural bonding, and Molecular bonding orbital (HOMOâLUMO) analysis are in favour of pyrrole-β substituted zinc porphyrins contrast to meso-phenyl dyads