Impacts of uplift of northern Tibetan Plateau and formation of Asian inland deserts on regional climate and environment

Based on the geological evidence that the northern Tibetan Plateau (NTP) had an uplift of a finite magnitude since the Miocene and the major Asian inland deserts formed in the early Pliocene, a regional climate model (RegCM4.1) with a horizontal resolution of 50 km was used to explore the effects of the NTP uplift and the related aridification of inland Asia on regional climate. We designed three numerical experiments including the control experiment representing the present-day condition, the high-mountain experiment representing the early Pliocene condition with uplifted NTP but absence of the Asian inland deserts, and the low-mountain experiment representing the mid-Miocene condition with reduced topography in the NTP (by as much as 2400 m) and also absence of the deserts. Our simulation results indicated that the NTP uplift caused significant reductions in annual precipitation in a broad region of inland Asia north of the Tibetan Plateau (TP) mainly due to the enhanced rain shadow effect of the mountains and changes in the regional circulations. However, four mountainous regions located in the uplift showed significant increases in precipitation, stretching from the Pamir Plateau in the west to the Qilian Mountains in the east. These mountainous areas also experienced different changes in the rainfall seasonality with the greatest increases occurring during the respective rainy seasons, predominantly resulted from the enhanced orographically forced upwind ascents. The appearance of the major deserts in the inland Asia further reduced precipitation in the region and led to increased dust emission and deposition fluxes, while the spatial patterns of dust deposition were also changed, not only in the regions of uplift-impacted topography, but also in the downwind regions. One major contribution from this study is the comparison of the simulation results with 11 existing geological records representing the moisture conditions from Miocene to Pliocene. The comparisons revealed good matches between the simulation results and the published geological records. Therefore, we conclude that the NTP uplift and the related formation of the major deserts played a controlling role in the evolution of regional climatic conditions in a broad region in inland Asia since the Miocene

Filter paper-templated preparation of ZnO thin films and examination of their gas-sensing properties

ZnO thin films were prepared by using quantitative filter paper as a template and 1.5 mol 3 CO 2 ) 2 ·2H 2 O ethanol solution and calcined at 600 °C. The ZnO nanoparticles prepared from fast-speed filter paper has a higher response to 120–205 ppm formaldehyde at 400 °C than those prepared from medium- or slow-speed paper

Filter paper-templated preparation of ZnO thin films and examination of their gas-sensing properties

ZnO thin films prepared by using quantitative filter paper as a template and Zn(CH(3)CO(2))(2)center dot 2H(2)O ethanol precursor solution were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The effects of sample calcination temperature, precursor concentration and filter paper types were studied, and the growth process was investigated by infra-red (IR) spectroscopy and thermogravimetric analysis/differential thermal analysis (TGA/DTA). The results show that samples soaked in a 1.5 mol/L Zn(CH(3)CO(2))(2)center dot 2H(2)O ethanol solution and calcined at 600 degrees C yield ZnO films of uniform particle size, approximately 30, 40 and 50 nm, for fast-, medium- and slow-speed filter papers, respectively. The formaldehyde gas sensing properties of the ZnO nanoparticles were tested, showing that the material prepared from fast-speed filter paper has a higher response to 120-205 ppm formaldehyde at 400 degrees C than that prepared from medium- or slow-speed paper, which depends on the particle size. (C) 2011 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved

Assessment of transverse impact damage in GF/EP laminates of conductive nanoparticles using electrical resistivity tomography

GF/EP composite laminates with an epoxy matrix modified by carbon black (CB) of 2.0 wt.% and copper chloride (CC) were manufactured by the vacuum assisted resin infusion (VARI) technique. The effects of CB nanoparticles and CC on improvement in Modes I and II interlaminar fracture toughness and impact damage resistance and on the electrical conductivity of GF/EP laminate composites were investigated. Delamination growth was calibrated by in situ electrical resistance changes during interlaminar fracture tests. The relationship between growth of delamination and change in electrical resistance was characterised. A damage index based on the change in electrical resistance was introduced, and a new method of electrical resistivity tomography was developed to access transverse impact damage in GF/EP laminates based on a matrix of conductive points in both in-plane and through-thickness directions. The damage images from in-plane and through-thickness electrical resistivity tomography were finally estimated with the corresponding C-scan. (c) 2012 Elsevier Ltd. All rights reserved

Protective Effects of Danhong Injection against Cerebral Damage during On-Pump Coronary Artery Bypass Graft Surgery

To explore the protective effects of Danhong injection against cerebral damage during on-pump coronary artery bypass graft surgery and its mechanism. Methods. Fifty patients scheduled for on-pump CABG surgery were randomly divided into Danhong injection group (group D) and control group (group C). Group D was given Danhong injection while group C was given the same volume of normal saline when the artery was cut open. Jugular bulb blood right before the operation began (T1), when body temperature rewarming to 36°C (T2), 30 min after the termination of cardiopulmonary bypass (T3), and 6 hrs after the termination of CPB (T4) was collected. The superoxide dismutase activity by using xanthine oxidase method and concentration determination of malondialdehyde were examined. Results. In group C, SOD activity was less at T2–T4 than at T1. It was also less active comparatively in group D at T2–T4. The MDA concentration increased in both groups but was more obvious in group C. Levels of TNF-α, IL-6, IL-8, and IL-10 increased in both groups C and D at T3 and T4, compared to T1. Conclusions. Danhong injection shows significant protective effects against cerebral damage during on-pump coronary artery bypass graft surgery

Tailorable Metal-Ceramic (Cu-TiC0.5) Layered Electrode with High Mechanical Property and Conductivity

Two-dimensional materials have been extensively investigated in the fields of electrochemical sensors, field-effect transistors, and other electronic devices due to their large surface areas, high compatibility with device integration, and so on. Conventional electrodes, such as precious metal layers that are deposited on polymer or silicon wafers, have gradually revealed increasing difficulties in adapting to various device structures, especially for twodimensional materials, which prefer high exposure of surface atoms. Here, we demonstrate a tailorable metal-ceramic (CuTiC0.5) layered structure as novel electrodes with high mechanical property and conductivity and fabricate a highly sensitive gas sensor with graphene lying on this proposed electrodes. The Cu-TiC0.5 layered structure exhibits remarkably high tensile yield strength and compressive yield strength, which increase 7 and 8 times than those of the pure copper, respectively. Meanwhile, excellent flexibility and conductivity could also be obtained with the further thinning of the Cu-TiC0.5 layered composite, which shows its potential applications in flexible electronics. Finally, we demonstrated that a graphene-based gas sensor fabricated on tailored metal-ceramic electrodes was ultrasensitive and robust, which benefits from the good thermal conductivity and peculiar gas channels etched on the surface of copper alloy electrodes

Atomic Coupling Growth of Graphene on Carbon Steel for Exceptional Anti-Icing Performance

Surface enrichment of regularly arranged C atoms on carbon steel (C-steel) substrates is intriguing but challenging due to the strong bonding force between C and Fe and complex C solubility in C-steel. We propose a novel strategy of introducing a supersaturated C isolating layer on the surface of C-steel to block the ceaseless C dissolution in bulk metal and directly grow graphene on C-steel through a controlled cooling process with selected C sources for the first time. The as-grown graphene films have strong atomic coupling with the adjacent C-steel substrate, and the presence of a gradient, structured cementite layer indicates a C diffusion blocking effect for the bulk. Finally, the novel composite exhibited an exceptional anti-icing ability

Preparation and anisotropic tribological properties of MoAlB/Al laminated composites

The unique microstructure of biomaterials provides inspiration in materials structure design and performance breakthroughs. Here we prepared a MoAlB reinforced Al matrix composites with laminated structure and strong interfacial bonding. This work mainly focuses on the relationship between tribological properties of the MoAlB/Al laminated composites and the MoAlB layer orientation. The results show that the tribological properties of the composites deeply depend on the relation of sliding direction VS. the MoAlB layer orientation, while the dependency gradually decreases with the MoAlB content increasing. The friction coefficient and wear rate of the composites can be decreased by 55.5% and 95.1%, lower than those of pure Al, when 15 vol% MoAlB reinforcement is added. The friction and wear mechanisms of the MoAlB/Al laminated composites are proposed, and the outstanding tribological properties are ascribed to the formation of tribochemical worn film and different stress states caused by the laminated structure

A Promising Crystalline KCl: Electrolyte Material for Studying the Electrochemical Properties of Cerium on Liquid Indium Electrodes

Potassium chloride crystals are good conductors in the UV to mid-infrared broadband and can be widely used as materials for high-power CO2 lasers. However, the most important use of potassium chloride crystals has been overlooked; their stable chemistry and wide electrochemical window allow them to form molten eutectic salts with other chlorides for the dry reprocessing of spent fuel. The aim of this work is to investigate the electrochemical properties of the actinide substitute cerium metal on liquid indium media in order to provide basic data for further realization of lanthanides (Ln)/actinides (An) separation. In this paper, we investigated the electrochemical behavior of 3LiCl-2KCl-CeCl3 melt at liquid metal media indium (In) electrode using various transient electrochemical analysis methods, such as cyclic voltammetry, square wave voltammetry and open circuit potential technique. The quasi-equilibrium potentials of Ce3+ at different temperatures on the liquid metal In electrode were determined. On the redox process, the reaction kinetics of the oxidation–reduction process in the 3LiCl-2KCl-CeCl3 system is studied. It was determined that the reduction of Ce3+ at the liquid metal In electrode is an irreversible single-step process with three electron transfers. The relationship between the diffusion coefficient and the reduction process of Ce3+ ions on liquid metal indium electrodes at different temperatures was determined. The expression for the diffusion coefficient and temperature of Ce3+ at the liquid metal indium electrode is: lnD = 1.43 − 7974.69/T

Hybrid structure of zinc oxide nanorods and three dimensional graphene foam for supercapacitor and electrochemical sensor applications

A hybrid structure of zinc oxide (ZnO) on three dimensional (3D) graphene foam has been synthesized by chemical vapor deposition (CVD) growth of graphene followed by a facial in situ precipitation of ZnO nanorods under hydrothermal conditions. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used to characterize the morphology and structure of graphene/ZnO hybrids. The results show that the ZnO nanorods have high crystallinity and cluster uniformly on graphene skeleton to form flower-like nanostructures. Serving as a free-standing electrode, the electrochemical and biosensing performance of graphene/ZnO hybrids are studied by cyclic voltammetry, electrochemical impedance spectroscopy, galvanostatic charge–discharge and amperometric measurements. It is found that the graphene/ZnO hybrids display superior capacitive performance with high specific capacitance (~400 F g−1) as well as excellent cycle life, making them suitable for high-performance energy storage applications. Furthermore, the graphene/ZnO hybrids exhibit high sensitivity for detection of [Fe(CN)6]3+ and dopamine, with the extrapolated lower detection limits of ~1.0 μM and ~10.0 nM respectively. These results demonstrate the potential of free-standing graphene/ZnO hybrid electrodes for the development of highly sensitive electrochemical sensors