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1.
ACS Nano ; 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38941591

ABSTRACT

High-performance thermal interface materials (TIMs) are highly desired for high-power electronic devices to accelerate heat dissipation. However, the inherent trade-off conflict between achieving high thermal conductivity and excellent compliance of filler-enhanced TIMs results in the unsatisfactory interfacial heat transfer efficiency of existing TIM solutions. Here, we report the graphene fiber (GF)-based elastic TIM with metal-level thermal conductivity via mechanical-electric dual-field synergistic alignment engineering. Compared with state-of-the-art carbon fiber (CF), GF features both superb high thermal conductivity of ∼1200 W m-1 K-1 and outstanding flexibility. Under dual-field synergistic alignment regulation, GFs are vertically aligned with excellent orientation (0.88) and high array density (33.5 mg cm-2), forming continuous thermally conductive pathways. Even at a low filler content of ∼17 wt %, GF-based TIM demonstrates extraordinarily high through-plane thermal conductivity of up to 82.4 W m-1 K-1, exceeding most CF-based TIMs and even comparable to commonly used soft indium foil. Benefiting from the low stiffness of GF, GF-based TIM shows a lower compressive modulus down to 0.57 MPa, an excellent resilience rate of 95% after compressive cycles, and diminished contact thermal resistance as low as 7.4 K mm2 W-1. Our results provide a superb paradigm for the directed assembly of thermally conductive and flexible GFs to achieve scalable and high-performance TIMs, overcoming the long-standing bottleneck of mechanical-thermal mismatch in TIM design.

2.
Org Lett ; 26(23): 4857-4862, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38838191

ABSTRACT

The efficient construction of π-conjugated polycyclic heteroarenes represents a significant task in the field of functional materials. A one-step oxidative tandem cyclization of aromatic acids with (benzo)thiophenes was developed to access planar sulfur-containing polycyclic heteroarenes. This protocol undergoes intermolecular cross-dehydrogenative coupling followed by intramolecular Friedel-Crafts acylation and provides a facile pathway to planar polycyclic compounds from inexpensive reactants. The synthesized heteroarenes serving as lipid-droplet-targeted probes exhibit outstanding performance with favorable biocompatibility and photostability.

3.
Adv Mater ; 36(28): e2402434, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38684233

ABSTRACT

To enhance the phototheranostic performance, agents with high reactive oxygen species (ROS) generation, good tumor-targeting ability, and prolonged retention are urgently needed. However, symmetric donor-acceptor (D-A) type agents usually produce spherical nanoaggregates, leading to good tumor targeting but inferior retention. Rod-like nanoaggregates are desired to extend their retention in tumors; however, this remains a challenge. In particular, agents with dynamically changeable shapes that integrate merits of different morphologies are seldomly reported. Therefore, self-assembled organic nanoaggregates with smart shape tunability are designed here using an asymmetric D-A type TIBT. The photoluminescence quantum yield in solids is up to 52.24% for TIBT. TIBT also exhibits high ROS generation in corresponding nanoaggregates (TIBT-NCs). Moreover, dynamic self-assembly in shape changing from nanospheres to nanorods occurrs in TIBT-NCs, contributing to the enhancement of ROS quantum yield from 0.55 to 0.72. In addition, dynamic self-assembly can be observed for both in vitro and in vivo, conferring TIBT-NCs with strong tumor targeting and prolonged retention. Finally, efficient photodynamic therapy to inhibit tumor growth is achieved in TIBT-NCs, with an inhibition rate of 90%. This work demonstrates that asymmetric D-A type agents can play significant roles in forming self-assembled organic nanoaggregates, thus showing great potential in long-acting cancer therapy.


Subject(s)
Photochemotherapy , Photosensitizing Agents , Reactive Oxygen Species , Photochemotherapy/methods , Reactive Oxygen Species/metabolism , Animals , Humans , Mice , Photosensitizing Agents/chemistry , Photosensitizing Agents/pharmacology , Cell Line, Tumor , Nanoparticles/chemistry , Neoplasms/drug therapy , Neoplasms/pathology
4.
Small ; : e2400468, 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38516967

ABSTRACT

Alloy-type antimony (Sb) and conversion-type molybdenum (Mo) anodes have attracted extensive attention in the application of lithium-ion batteries (LIBs) owing to their high theoretical capacity. In this study, Sb2MoO6 nanowires are prepared via a hydrothermal method and assessed their thermal behavior upon heat treatment, observing an intriguing transformation from nanowire to Sb2O3/MoOx nanosheets. To enhance structure stability, the Sb2MoO6 nanowires are successfully coated with a polyphosphazene layer (referred to as PZS@Sb2MoO6), which not only preserved the nanowires form but also yielded N/S co-doped carbon-coated SbPO4/MoOx (NS-C@SbPO4/MoOx) nanowires following annealing in an inert environment. This composite benefits from the stable PO4 3- anion that serve as a buffer against volume expansion and form a Li3PO4 matrix during cycling, both of which substantially bolster ion transport and cycle endurance. Doping with heteroatoms introduces numerous oxygen vacancies, augmenting the number of electrochemically active sites, and carbon integration considerably enhances the electronic conductivity of the electrode and alleviates the volume-change-induced electrode pulverization. Employed as anode materials in LIBs, the NS-C@SbPO4/MoOx electrode exhibits remarkable cycling performance (449.8 mA h g-1 at 1000 mA g-1 over 700 cycles) along with superior rate capability (394.2 mA h g-1 at 2000 mA g-1).

5.
Nano Lett ; 24(10): 3005-3013, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38416810

ABSTRACT

Most aggregation-induced emission (AIE) luminogens exhibit high brightness, excellent photostability, and good biocompatibility, but these AIE-active agents, which kill two birds with one stone to result in applications in both stimulated emission depletion (STED) super-resolution imaging and photodynamic therapy (PDT), have not been reported yet but are urgently needed. To meet the requirements of STED nanoscopy and PDT, D-A-π-A-D type DTPABT-HP is designed by tuning conjugated π spacers. It exhibits red-shifted emission, high PLQY of 32.04%, and impressive 1O2 generation (9.24 fold compared to RB) in nanoparticles (NPs). Then, DTPABT-HP NPs are applied in cell imaging via STED nanoscopy, especially visualizing the dynamic changes of lysosomes in the PDT process at ultrahigh resolution. After that, in vivo PDT was also conducted by DTPABT-HP NPs, resulting in significantly inhibited tumor growth, with an inhibition rate of 86%. The work here is beneficial to the design of multifunctional agents and the deep understanding of their phototheranostic mechanism in biological research.


Subject(s)
Nanoparticles , Neoplasms , Photochemotherapy , Humans , Photosensitizing Agents/therapeutic use , Diagnostic Imaging , Neoplasms/drug therapy , Photochemotherapy/methods
6.
Nanomicro Lett ; 16(1): 58, 2023 Dec 19.
Article in English | MEDLINE | ID: mdl-38112845

ABSTRACT

Highly thermally conductive graphitic film (GF) materials have become a competitive solution for the thermal management of high-power electronic devices. However, their catastrophic structural failure under extreme alternating thermal/cold shock poses a significant challenge to reliability and safety. Here, we present the first investigation into the structural failure mechanism of GF during cyclic liquid nitrogen shocks (LNS), which reveals a bubbling process characterized by "permeation-diffusion-deformation" phenomenon. To overcome this long-standing structural weakness, a novel metal-nanoarmor strategy is proposed to construct a Cu-modified graphitic film (GF@Cu) with seamless heterointerface. This well-designed interface ensures superior structural stability for GF@Cu after hundreds of LNS cycles from 77 to 300 K. Moreover, GF@Cu maintains high thermal conductivity up to 1088 W m-1 K-1 with degradation of less than 5% even after 150 LNS cycles, superior to that of pure GF (50% degradation). Our work not only offers an opportunity to improve the robustness of graphitic films by the rational structural design but also facilitates the applications of thermally conductive carbon-based materials for future extreme thermal management in complex aerospace electronics.

7.
Water Sci Technol ; 79(11): 2086-2094, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31318346

ABSTRACT

Activated carbon made from agricultural waste (walnut shells) was investigated as a suitable adsorbent for effectively removing quinoline from industrial wastewater. The activated carbon was treated with phosphoric acid and oxidized by ammonium persulfate and its ability to adsorb pyridine and quinoline in aqueous solution was investigated. Kinetic parameters for the adsorption process were determined through pseudo-first-order and pseudo-second-order kinetic models and intraparticle diffusion models. Equilibrium experiments and adsorption isotherms were analyzed using Langmuir and Freundlich adsorption isotherms. After reaching equilibrium, the activated carbon adsorbed quinoline in preference to pyridine: the equilibrium adsorptions from individual aqueous solutions (200 µL L-1) of quinoline and pyridine were 166.907 mg g-1 and 72.165 mg g-1, respectively. Thermodynamic studies of quinoline adsorption were conducted at different temperatures and indicated that quinoline adsorption was an endothermic and spontaneous process. The column-adsorption of quinoline and pyridine was consistent with the Thomas model and the Yoon-Nelson model. The removal efficiency of quinoline reached more than 97% for a velocity of 6 mL min-1 at the initial adsorption stage.


Subject(s)
Quinolines/chemistry , Water Pollutants, Chemical/chemistry , Adsorption , Ammonium Sulfate/chemistry , Charcoal , Hydrogen-Ion Concentration , Juglans/chemistry , Kinetics , Models, Chemical , Quinolines/analysis , Solutions , Thermodynamics , Water Pollutants, Chemical/analysis
8.
Article in English | MEDLINE | ID: mdl-24827282

ABSTRACT

The cytoskeleton is a network of crosslinked, semiflexible filaments, and it has been suggested that it has properties of a glassy state. Here we employ optical-trap-based microrheology to apply forces to a model cytoskeleton and measure the high-bandwidth response at an anterior point. Simulating the highly nonlinear and anisotropic stress-strain propagation assuming affinity, we found that theoretical predictions for the quasistatic response of semiflexible polymers are only realized at high frequencies inaccessible to conventional rheometers. We give a theoretical basis for determining the frequency when both affinity and quasistaticity are valid, and we discuss with experimental evidence that the relaxations at lower frequencies can be characterized by the experimentally obtained nonaffinity parameter.


Subject(s)
Cytoskeletal Proteins/physiology , Cytoskeleton/physiology , Intermediate Filament Proteins/physiology , Mechanotransduction, Cellular/physiology , Animals , Compressive Strength/physiology , Elastic Modulus/physiology , Humans , Stress, Mechanical , Tensile Strength/physiology , Viscosity
9.
Zhonghua Zhong Liu Za Zhi ; 35(8): 623-6, 2013 Aug.
Article in Chinese | MEDLINE | ID: mdl-24314223

ABSTRACT

OBJECTIVE: To compare the efficacy and side effects of induction chemotherapy with vinorelbine plus cisplatin (NP) or docetaxel plus cisplatin (TP) combined with concurrent chemoradiotherapy in treating locally advanced nasopharyngeal carcinoma (NPC). METHODS: From January 2005 to December 2009, 146 patients with locally advanced nasopharyngeal carcinoma treated in our department were randomized into NP group (76 patients) or TP group (70 patients). Both groups received two cycles of induction chemotherapy and concurrent chemoradiotherapy. After three weeks of induction chemotherapy, the patients received concurrent chemoradiotherapy. The chemotherapy was recycled every three weeks. Two groups were treated with intensity-modulated radiation therapy. RESULTS: The short-term efficacy of NP group was similar to that of TP group. The 3-year overall survival rates, disease-free-survival rates, locoregional relapse-free survival rates and distant metastasis-free survival rates in the NP and TP groups were 84.2% and 82.9%, 71.1% and 74.3%, 89.5% and 91.4%, 81.6% and 77.1%, respectively (P > 0.05). The occurrence rates of leucopenia, anemia and acute mucositis were significantly higher in the TP group than those in the NP group (P < 0.05). The gastrointestinal toxicity, dermatitis and liver toxicity were similar in the two groups. CONCLUSIONS: The efficacy of NP regimen induction chemotherapy plus concurrent chemordiotherapy for advanced NPC is similar to that of TP regimen. The toxicity of the NP regimen is lower than that of NP regimen, tolerable, and with a good compliance.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Chemoradiotherapy , Induction Chemotherapy , Nasopharyngeal Neoplasms/therapy , Radiotherapy, Intensity-Modulated , Adult , Aged , Bone Neoplasms/secondary , Carcinoma , Cisplatin/administration & dosage , Cisplatin/adverse effects , Disease-Free Survival , Docetaxel , Female , Follow-Up Studies , Humans , Leukopenia/chemically induced , Leukopenia/etiology , Liver Neoplasms/secondary , Lung Neoplasms/secondary , Male , Middle Aged , Mucositis/chemically induced , Mucositis/etiology , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/pathology , Neoplasm Recurrence, Local , Neoplasm Staging , Remission Induction , Survival Rate , Taxoids/administration & dosage , Taxoids/adverse effects , Vinblastine/administration & dosage , Vinblastine/adverse effects , Vinblastine/analogs & derivatives , Vinorelbine , Young Adult
10.
Oncol Rep ; 20(5): 1099-103, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18949407

ABSTRACT

Bladder cancer is a common but serious malignancy. It is widely accepted that chemoprevention may be an effective way to decrease the rate of recurrence and morbidity. We first determined antigrowth and apoptosis-induction activity of fucoxanthin from dietary Laminaria japonica against EJ-1 human bladder cancers. Fucoxanthin significantly reduced the cell viability in a dose- and time-dependent manner. The induction of apoptosis in EJ-1 cells was characterized by morphological changes, DNA ladder, and increased percentage of hypodiploid cells, activating caspase-3 activity. The ratio of apoptotic cells reached >93% after treatment for 72 h with 20 microM fucoxanthin. The findings obtained indicate that fucoxanthin may act as a chemopreventive and/or chemotherapeutic carotenoid in bladder cancer cells by modulating cell viability.


Subject(s)
Antineoplastic Agents/pharmacology , Urinary Bladder Neoplasms/prevention & control , Xanthophylls/pharmacology , Apoptosis/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Chemoprevention , Diet , Flow Cytometry , Humans , Reactive Oxygen Species
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