Inhibition of Oxyanions on Redox-driven Transformation of Layered Manganese Oxides
Not Available
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Engineering topics
Wu, Juan
Publications and source records attributed to Wu, Juan.
Four-Dimensional Imaging of ZnO-Coated Alumina Aerogels by Scanning Transmission X-ray Microscopy and Ptychographic Tomography
Functional porous materials are of mounting significance in energy conversion and catalysis. Improved analysis is needed to guide optimization. Four-dimensional (4D) imaging [chemical mapping in three-dimensional (3D) by spectro-tomography] of an Al 2 O 3 aerogel coated with ZnO by atomic layer deposition was performed using soft X-ray ptychography at the Zn L-edge. A two-dimensional spatial resolution of 14(2) nm was achieved. Visualizations of the 3D chemical structure are provided. The degree of ZnO coverage of the surface of the Al 2 O 3 aerogel framework in two different samples was estimated and found to be both thicker and less homogeneous than expected. Other analyses of the 4D results, including the degree of contact between Al 2 O 3 and ZnO, were extracted from the reconstructed 3D data. This pioneering soft X-ray spectro-ptycho-tomography research will anchor further studies of functional porous materials.
36 MATERIALS SCIENCE↗
Monocarboxylate transporters in breast cancer and adipose tissue are novel biomarkers and potential therapeutic targets
Monocarboxylate transporters (MCTs) are transmembrane proteins that control the lactate metabolism and associated with poor prognosis in solid tumours including breast cancer (BC). This study aimed to evaluate the clinical and prognostic value of MCTs used by immunohistochemistry and quantum dots-based fluorescent imaging technique in BC and surrounding stroma with emphasis on the interaction between tumour and stroma. Moreover, the data from The Cancer Genome Atlas (TCGA) was analyzed to evaluate the association between MCTs mRNA expression and prognosis of breast cancer patients. Our study found that MCT1 overexpression was observed in hormone receptor-negative and high-proliferation subtypes. High expression of MCT1 and MCT4 in tumour tissues was associated with poor patient outcome; further the correlation between MCT1 expression and poor prognosis in breast cancer was further strengthened when combined with MCT4 overexpression in the adjacent adipose tissue. These results demonstrate that MCTs tend to play a role in the aggressive BC subtypes through the dynamic interaction between breast cancer cells and adipocytes, and developing therapeutics to block this interaction will be a promising strategy in cancer therapy.
60 APPLIED LIFE SCIENCES↗
Au nanoparticles and graphene oxide co-loaded graphitic carbon nitride: Synthesis and photocatalytic application
Highlights: • The 0.5%Au/GO/g-C3N4 composite exhibites excellent photocatalytic activity. • GO nanoslice acts as an e- transporter and acceptor Au/GO/g-C3N4 composite. • Au particles in Au/GO/g-C3N4 composite act as electron trap to separate e- and h{sup +}. • Adsorbed OH and h{sup +} are involved in reducing and oxidizing process, respectively. - Abstract: Inhibition of charge-carrier recombination in semiconductors is one of the most efficient methods to enhance the photocatalytic performance in visible light irradiation. Noble metals and graphene oxide (GO) are currently regarded as fine channels to enhance the charge-carrier transfer efficiency. Herein, novel Au nanoparticles and GO co-loaded graphitic carbon nitride (Au/GO/g-C{sub 3}N{sub 4}) composite was obtained by a single step ultrasonic chemical process, and the photocatalytic activity was tested in Rhodamine B (Rh B) photodegradation in visible light region. The Au/GO/g-C{sub 3}N{sub 4} composite containing 0.5%Au (molar Au per unit molar of g-C{sub 3}N{sub 4}) exhibited excellent photocatalytic activity and might be attributed to the important part of GO nanoslices and Au nanoparticles. An electron transporter and acceptor have been acted by the GO nanoslices to facilitate the charge transfer and against the recombination of photoexcited electron-hole pairs. In the meantime, an electron trap was formed on the Au nanoparticles to separate the charges. Furthermore, it was found that the reactive species of adsorbed OH and holes took part in the reduction and oxidization actions in the photocatalytic process, respectively. The design of the Au/GO/g-C{sub 3}N{sub 4} composite provides a novel route to synthesis of highly efficient photocatalysts in environmental application.
36 MATERIALS SCIENCE↗
Hydrothermal stability of SAPO-34 for refrigeration and air conditioning applications
Graphical abstract: The SAPO-34 was synthesized by a hydrothermal method using diethylamine as a template. Water adsorption strength on SAPO-34 is between that on 13X and A type silica gel. During 100–400 Pa, the water uptake on SAPO-34 increases sensitively to pressure, and equilibrium water uptake reaches 0.35 kg/kg, 25% higher than 13X. SAPO-34 shows no significant reduced cyclic water uptake over 60 cycles. Most of the initial SAPO-34 phase is restored, while the regular cubic-like morphology is well maintained, and the specific surface area only decreases by 8.6%. - Highlights: • Water adsorption strength on SAPO-34 is between that on 13X and A type silica gel. During 100–400 Pa, the water uptake on SAPO-34 increases sensitively to pressure, and equilibrium water uptake reaches 0.35 kg/kg, 25% higher than 13X. • SAPO-34 with diethylamine as the template shows no significant reduced cyclic water uptake over 60 cycles, and most of the initial SAPO-34 phase is well maintained. • SAPO-34 has an excellent adsorption performance and a good hydrothermal stability, thus is promising for application in adsorption refrigeration. - Abstract: Hydrothermal stability is one of the crucial factors in applying SAPO-34 molecular sieve to adsorption refrigration. The SAPO-34 was synthesized by a hydrothermal method using diethylamine as a template. Both a vacuum gravimetric method and an intelligent gravimetric analyzer were applied to analyze the water adsorption performance of SAPO-34. Cyclic hydrothermal performance was determined on the modified simulation adsorption refrigeration test rig. Crystal phase, morphology, and porosity of SAPO-34 were characterized by X-ray diffraction, scanning electron microscopy, and N{sub 2} sorption, respectively. The results show that, water adsorption strength on SAPO-34 is between that on 13X and A type silica gel. During 100–400 Pa, the water uptake on SAPO-34 increases sensitively to pressure, and equilibrium water uptake reaches 0.35 kg/kg, 25% higher than 13X. SAPO-34 shows no significant reduced cyclic water uptake over 60 cycles. Most of the initial SAPO-34 phase is restored, while the regular cubic-like morphology is well maintained, and the specific surface area only decreases by 8.6%.
36 MATERIALS SCIENCE↗
Array detector for high energy laser based on diffuse transmission sampling
In order to improve the ability and accuracy of measuring the temporal–spatial distribution of the intensity of a large-size, high-energy laser beam, a novel array detecting method based on diffuse transmission sampling is proposed. The measurement principle and the design of the sampling and attenuating unit are presented. High-temperature-resistant diffuse transmission material is used to sample and attenuate a high energy laser beam. Pure copper, whose surface is first sand-blasted and then gold-plated, is applied to scatter the incident high-energy laser beam. The formula for the attenuation ratio was derived in detail. We developed two large-aperture array detectors with spatial resolution of 5 mm, spatial duty ratio of 20%, and useable angle range of ±30° without varying the responsivity, the non-uniformity in the laser profile measurement is below 1%, and the repeatability error in the laser power measurement is approximately 1%. The maximal energy density that the array detector can endure is more than 10 kJ/cm{sup 2}.
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
Electrical Switching of Perovskite Thin-Film Resistors
Electronic devices that exploit electrical switching of physical properties of thin films of perovskite materials (especially colossal magnetoresistive materials) have been invented. Unlike some related prior devices, these devices function at room temperature and do not depend on externally applied magnetic fields. Devices of this type can be designed to function as sensors (exhibiting varying electrical resistance in response to varying temperature, magnetic field, electric field, and/or mechanical pressure) and as elements of electronic memories. The underlying principle is that the application of one or more short electrical pulse(s) can induce a reversible, irreversible, or partly reversible change in the electrical, thermal, mechanical, and magnetic properties of a thin perovskite film. The energy in the pulse must be large enough to induce the desired change but not so large as to destroy the film. Depending on the requirements of a specific application, the pulse(s) can have any of a large variety of waveforms (e.g., square, triangular, or sine) and be of positive, negative, or alternating polarity. In some applications, it could be necessary to use multiple pulses to induce successive incremental physical changes. In one class of applications, electrical pulses of suitable shapes, sizes, and polarities are applied to vary the detection sensitivities of sensors. Another class of applications arises in electronic circuits in which certain resistance values are required to be variable: Incorporating the affected resistors into devices of the present type makes it possible to control their resistances electrically over wide ranges, and the lifetimes of electrically variable resistors exceed those of conventional mechanically variable resistors. Another and potentially the most important class of applications is that of resistance-based nonvolatile-memory devices, such as a resistance random access memory (RRAM) described in the immediately following article, Electrically Variable Resistive Memory Devices (MFS-32511-1).
Liu, Shangqing↗