scispace - formally typeset
Search or ask a question
Author

Qian Zhang

Bio: Qian Zhang is an academic researcher from Chinese Academy of Sciences. The author has contributed to research in topics: Thermoelectric effect & Thermoelectric materials. The author has an hindex of 56, co-authored 638 publications receiving 14885 citations. Previous affiliations of Qian Zhang include Radboud University Nijmegen Medical Centre & Northeast Normal University.


Papers
More filters
Journal ArticleDOI
TL;DR: Understanding the novel function of autophagy may allow us to develop a promising therapeutic strategy to enhance the effects of chemotherapy and improve clinical outcomes in the treatment of cancer patients.
Abstract: Induction of cell death and inhibition of cell survival are the main principles of cancer therapy. Resistance to chemotherapeutic agents is a major problem in oncology, which limits the effectiveness of anticancer drugs. A variety of factors contribute to drug resistance, including host factors, specific genetic or epigenetic alterations in the cancer cells and so on. Although various mechanisms by which cancer cells become resistant to anticancer drugs in the microenvironment have been well elucidated, how to circumvent this resistance to improve anticancer efficacy remains to be defined. Autophagy, an important homeostatic cellular recycling mechanism, is now emerging as a crucial player in response to metabolic and therapeutic stresses, which attempts to maintain/restore metabolic homeostasis through the catabolic lysis of excessive or unnecessary proteins and injured or aged organelles. Recently, several studies have shown that autophagy constitutes a potential target for cancer therapy and the induction of autophagy in response to therapeutics can be viewed as having a prodeath or a prosurvival role, which contributes to the anticancer efficacy of these drugs as well as drug resistance. Thus, understanding the novel function of autophagy may allow us to develop a promising therapeutic strategy to enhance the effects of chemotherapy and improve clinical outcomes in the treatment of cancer patients.

968 citations

Journal ArticleDOI
TL;DR: This work studied the thermoelectric properties of nanostructured SnTe with different dopants, and found indium-doped SnTe showed extraordinarily large Seebeck coefficients that cannot be explained properly by the conventional two-valence band model.
Abstract: From an environmental perspective, lead-free SnTe would be preferable for solid-state waste heat recovery if its thermoelectric figure-of-merit could be brought close to that of the lead-containing chalcogenides. In this work, we studied the thermoelectric properties of nanostructured SnTe with different dopants, and found indium-doped SnTe showed extraordinarily large Seebeck coefficients that cannot be explained properly by the conventional two-valence band model. We attributed this enhancement of Seebeck coefficients to resonant levels created by the indium impurities inside the valence band, supported by the first-principles simulations. This, together with the lower thermal conductivity resulting from the decreased grain size by ball milling and hot pressing, improved both the peak and average nondimensional figure-of-merit (ZT) significantly. A peak ZT of ∼1.1 was obtained in 0.25 atom % In-doped SnTe at about 873 K.

614 citations

Journal ArticleDOI
TL;DR: The ultra fine nanosized TiO2 photocatalysts in anatase, rutile, and both phases were prepared by the hydrolysis of TiCl4 solution as discussed by the authors.
Abstract: The ultra fine nanosized TiO2 photocatalysts in the anatase, rutile, and both phases were prepared by the hydrolysis of TiCl4 solution The resulting materials have been characterized by HREM, XRD, BET and UV–VIS absorption spectroscopy The photoactivity, effective degradation, and the selectivity for complete mineralization of these catalysts were tested in the photocatalytic degradation of phenol For this reaction, the quantum-sized catalyst particles (4 nm) in the anatase phase shows the highest selectivity, the concentrations of p-benzoquinone and hydroquinol as the photocatalytic products were at very low level However, the selectivity of the quantum-sized crystallites in the rutile phase was not improved in comparison with that of catalysts which bandgap corresponding bulk rutile HREM micrographs show the quantum-sized catalysts were crystallized partially or many defects occurred on their crystal planes, they are responsible for their relative low photoactivity Calcination is an effective treatment to increase the photoactivity of nanosized TiO2 photocatalysts resulting from the improvement of crystallinity Mixtures of both phases exhibit higher photoactivity as well as effective degradation in comparison with pure anatase or rutile catalysts To the best of our knowledge, we are first to report that the quantum-sized TiO2 crystallite exhibit high selectivity for complete mineralization in the photocatalytic degradation of phenol solution

552 citations

Journal ArticleDOI
TL;DR: In this paper, the authors showed that good reproducibility can be achieved by introducing an optimal concentration of 0.01 copper (Cu) per Bi2Te2.7Se0.3 samples without texturing.
Abstract: Combining high energy ball-milling and hot-pressing, significant enhancements of the thermoelectric figure-of-merit (ZT) have been reported for p-type Bi0.4Sb1.6Te3 nanocomposites. However, applying the same technique to n-type Bi2Te2.7Se0.3 showed no improvement on ZT values, due to the anisotropic nature of the thermoelectric properties of n-type Bi2Te2.7Se0.3. Even though texturing was effective in improving peak ZT of Bi2Te2.7Se0.3 from 0.85 to 1.04, reproducibility from batch to batch remains unsatisfactory. Here, we show that good reproducibility can be achieved by introducing an optimal concentration of 0.01 copper (Cu) per Bi2Te2.7Se0.3 to make Cu0.01Bi2Te2.7Se0.3 samples. A peak ZT value of 0.99 was achieved in Cu0.01Bi2Te2.7Se0.3 samples without texturing. With texturing by re-pressing, the peak ZT was increased to 1.06. Aging in air for over 5 months did not deteriorate but further improved the peak ZT to 1.10. The mechanism by which copper improves the reproducibility, enhances the carrier mobility, and reduces the lattice thermal conductivity is also discussed.

519 citations

Journal ArticleDOI
TL;DR: A global survey covering 196 dry inland waters shows that their CO2 emissions share fundamental drivers and constitute a substantial fraction of the carbon cycled by inland waters, increasing current inland water carbon flux estimates by 6%.
Abstract: Many inland waters exhibit complete or partial desiccation, or have vanished due to global change, exposing sediments to the atmosphere. Yet, data on carbon dioxide (CO2) emissions from these sedim ...

474 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: In this paper, photo-induced superhydrophilicity was used on the surface of a wide-band gap semiconductor like titanium dioxide (TiO 2 ) for photocatalytic activity towards environmentally hazardous compounds.

4,241 citations

Journal Article
TL;DR: In this article, the authors present a document, redatto, voted and pubblicato by the Ipcc -Comitato intergovernativo sui cambiamenti climatici - illustra la sintesi delle ricerche svolte su questo tema rilevante.
Abstract: Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui affronteremo l’attuale problema dei mutamenti climatici. Presentiamo il documento redatto, votato e pubblicato dall’Ipcc - Comitato intergovernativo sui cambiamenti climatici - che illustra la sintesi delle ricerche svolte su questo tema rilevante.

4,187 citations

Journal ArticleDOI
26 Mar 2013-ACS Nano
TL;DR: The properties and advantages of single-, few-, and many-layer 2D materials in field-effect transistors, spin- and valley-tronics, thermoelectrics, and topological insulators, among many other applications are highlighted.
Abstract: Graphene’s success has shown that it is possible to create stable, single and few-atom-thick layers of van der Waals materials, and also that these materials can exhibit fascinating and technologically useful properties. Here we review the state-of-the-art of 2D materials beyond graphene. Initially, we will outline the different chemical classes of 2D materials and discuss the various strategies to prepare single-layer, few-layer, and multilayer assembly materials in solution, on substrates, and on the wafer scale. Additionally, we present an experimental guide for identifying and characterizing single-layer-thick materials, as well as outlining emerging techniques that yield both local and global information. We describe the differences that occur in the electronic structure between the bulk and the single layer and discuss various methods of tuning their electronic properties by manipulating the surface. Finally, we highlight the properties and advantages of single-, few-, and many-layer 2D materials in...

4,123 citations