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In this work, flower-like molybdenum disulfide was constructed on the surface of ZIF-8-derived nitrogen-doped dodecahedral carbon (ZNC) for the electrocatalytic degradation of phenol. The flower-like nanostructure of MoS

CO2 laser double-wire MIG hybrid welding with direct current is a kind of process with high metal deposition rate and large weld penetration. Microscopic interaction model between the laser plasma and two arcs is proposed. Forces acting on the laser plasma and droplet were analyzed. A high speed camera system and an electrical signal acquisition system were used to investigate the coupling and metal transfer. The theoretical analysis and experimental results reveal that when the electromagnetic force of the leading arc on the laser plasma (FLP) is generally equal to the electromagnetic force of the trailing arc on the laser plasma (FTP), there is higher electron density in two lower sides of the laser plasma. Therefore, despite the great electromagnetic force, the two arcs do not deflect from the wire axis. A stable, spatter-free spray transfer can be achieved. When FLP > FTP, there is higher electron density in the upper left side and the lower right side of the laser plasma. Consequently, the trailing arc will deviate from the wire axis under the influence of the electromagnetic force, resulting in an unstable metal transfer with large spatter. Similarly, when FLP

In this study, a new type of deicing salt was prepared to overcome the disadvantages of using traditional chlorine deicing salts. As the main component of deicing salt with calcium chloride, aluminum chloride and ferric chloride were extracted from red mud, and calcium hydroxide as the pH adjusting agent. Freezing points of this deicing salt (Ca-Al-Fe deicing salt) were determined at concentrations of 5, 10, 20, 30 and 40 wt%, and the numerical values were in the range of −6.6 to −22.5 °C. A dense layer of precipitation membrane can be generated on the concrete surface when the Ca-Al-Fe deicing salt adsorbed chloride ion. By the XRD test, the main components of the precipitation membrane are Ca2Al(OH)6Cl·2H2O and FeOOH. In order to improve the frost resistance of the precipitation membrane, sodium methyl silicate was added as hydrophobic agent. A hydrophobic layer was formed on the surface of the precipitation membrane. After the formation of hydrophobic layer, the water absorption rate of concrete is reduced and the frost resistance is enhanced significantly.

The KxWO3 nanorods with a broad optical absorbance in near infrared (NIR) region have been synthesized by a facile solvothermal reaction in this work. On the merits of this unique photoabsorption, KxWO3 nanorod exhibited an excellent photothermal conversion effect upon NIR 1064 nm laser excitation as evidenced by a rapid, distinct and recyclable photothermal effect both for KxWO3 powder and aqueous dispersion. Further, KxWO3 was finally proved to be an eligible phototherapeutic agent for antitumor treatment and great success has been made in in vitro cancer cell killing and in vivo elimination of solid tumor in living mice, manifesting a potential application prospect of KxWO3 nanorod as photothermal material.

Oridonin has significant liver-protective effects, but its effect on liver steatosis has not been reported. We investigated the effects of oridonin on liver steatosis by cell cultures. The optimal experimental concentration of oridonin was determined through cytotoxicity experiments. A simple steatosis liver cell model was induced using free fatty acids (FFA). After adding oridonin to the FFA-induced cell model for 24 h, the lipid droplets and triglyceride (TG) content in the cells were measured by Oil Red O staining and TG kits. The expressions of autophagy-related markers (cyclin dependent kinases inhibitor 1a (p21), Beclin-1, microtubule-associated protein light chain 3 (LC3)-I and LC3-II, protein kinase B (AKT), phosphorylated-AKT (p-AKT), AMP-activated protein kinase (AMPK), and phosphorylated-AMPK (p-AMPK)) were detected by Western blot. Based on the results, the cell model was further treated by autophagy inhibitor 3-methyladenine (3-MA) to determine the degree of steatosis and the expressions of autophagy-related factors. Oridonin at a concentration higher than 10 μmol/L caused cytotoxicity to the cells. Adding 10 μmol/L oridonin to the FFA-induced cell model effectively reduced lipid droplets and TG content in the cells. Oridonin up-regulated p21, Beclin-1 and LC3-II expressions, but down-regulated those of p62 and LC3-I. Also, oridonin increased the ratios of LC3-II/LC3-I and p-AMPK/AMPK, but reduced that of p-AKT/AKT. With the addition of 3-MA, the effect of oridonin on reducing steatosis was partially reversed, and the autophagy was inhibited. This study found that oridonin can activate autophagy, thereby preventing simple steatosis of liver cells.

We conducted the first real-world study of treatment with omalizumab, a humanized monoclonal anti-immunoglobulin E antibody, in Chinese patients with severe allergic asthma.The primary objective was the steroid-sparing effect of omalizumab after 12 and 16 weeks of treatment. Characteristics of the patient population, treatment patterns, response rate, and other measures of therapeutic effectiveness were also reported.This nationwide, retrospective, real-world study was conducted in patients with severe allergic asthma who were treated with omalizumab in China. Data, including demographics, Asthma Control Test (ACT) and laboratory and lung function test results, and omalizumab use information, were extracted from patient records collected as part of a previously conducted real-world survey (Asthma Group of the Respiratory Disease Society of the Chinese Medical Association).In total, 139 patient records were included; 131 and 118 patients remained on treatment at the ≥12- and ≥16-week time points, respectively. The mean ± standard deviation age and median asthma duration (interquartile range) were 47.4 ± 14.3 and 7 (4, 15) years, respectively; 75.6% of patients had a history of allergic disease. Reductions (versus baseline) in inhaled corticosteroid/long-acting β2 agonists or oral corticosteroids were reported in 61.1% and 63.6% of patients at ≥12 and ≥ 16 weeks, respectively. There were significant improvements in ACT scores (6.08, P .001) and nitric oxide fraction in exhaled air (-13.0, P = .01) from baseline. Multivariate analysis revealed that age and allergic medical history were predictors of omalizumab treatment response. No serious adverse events were reported.Real-world omalizumab treatment was efficacious and well-tolerated in Chinese patients with severe allergic asthma.

To study water droplet dynamic behavior in the silicone oil under a uniform DC electric field, a visual experiment system is set up. Two parallel plates are placed to form a uniform DC electric field. Results show when the electric field intensity is less than 2.33 kV/cm, with the increase of the electric field intensity, the droplet stretches in the vertical direction. The droplet detaches from the lower plate at 2.45 kV/cm. The droplet breaks into two daughter droplets at 3.67 kV/cm. Two daughter droplets coalesce at 4.67 kV/cm. A liquid bridge is formed at 4.93 kV/cm.

The effects of zeolite structure and acidity on catalyst life of methanol to aromatic (MTA) reactions have been investigated using a number of MFI zeolites with different degrees of mesoporosity and acidity, which were obtained via the post-synthetic desilication with tetrapropylammonium hydroxide. The influence of the post-synthesis on the pore characteristics of the ZSM-5 zeolites were studied by combined N 2 adsorption/desorption and temperature programmed desorption of n-octane (n-octane-TPD) techniques. The acidity were quantitatively analysed by NH 3 -TPD and acetonitrile-TPD. The results indicated that the desilication increased the mesoporosity and decreased the strong acid density, which inhibited the coke formation and then increased the catalytic stability. NH 3 -TPD and FT-IR techniques were used to characterize the changes of the partially deactivated catalysts. It suggests that deactivation and the decrease of aromatic selectivity are associated with the reduction in the strong Bronsted sites.

In this study, a new ceramic filter material was prepared by recovering red mud from red mud at atmospheric pressure. The primary objective of this research was to investigate the effects of SiO 2 quantity and sintering temperature (ST) on the porosity, stability, microstructure, and performance of the resulting materials. The results demonstrated that after a two-step leaching process with 3 M HCl and 90% sulfuric acid, the recovery of SiO 2 from red mud exceeded 80%. The SiO 2 extracted from red mud was used as the main material and mixed with other materials including Na-bentonite, limestone and pulverized coal at a ratio of 65:25:8:2, resulting in a ceramic filter material with favorable chemical stability, high strength, and nontoxicity. The enhanced surface activity of the material can be attributed to the abundant Si-OH groups, which enable it suitable for the ammonia nitrogen removal from drinking water. Overall, silicon dioxide extracted from red mud will help solve the stockpile and pollution problems of it in China.

For over a century, the electric Potential Gradient (PG) of the atmosphere has been measured and studied. The local vertical electric field (Ez) is strongly influenced by the presence of lightning, electrified clouds, rainfall, aerosols, and many others. The One Year Electric Field Study-North Slope of Alaska (OYES-NSA) field campaign was established in the summer of 2017 to measure the vertical electric field at the ARM site in Barrow, Alaska alongside a wide array of supplementary instrumentation, including a Micro-Pulse Lidar and upward facing Ka-band radar. Two years of observations (072017-062019) have shown the possibility to quantify the local effects from aerosols and clouds observed by the Lidar and Radar on the measured EZ. Throughout the manuscript, the physics convention of negative downward fair-weather electric fields is used. Three cases (convective clouds, high concentration of near surface aerosols, and blowing snow) are used to demonstrate the localized effects on the measured EZ. Utilizing the relationships between EZ and backscatter/reflectivity, we have developed a methodology to distinguish samples with local influences. A fair-weather (FW) condition is determined to be associated with a low Lidar backscattering (less than 15 km−1sr−1), in the presence of no significant cloud activity (radar reflectivity less than −10dBZ). The samples satisfying these criteria are found with a 5-min averaged standard deviation of less than 15 V/m, and EZ between −250 V/m to −50 V/m. Using only properties of the EZ measurements allows for the simultaneous comparisons of FW at multiple sites, without the need for supplementary information of local weather conditions. Simultaneous EZ measurements from 8 FW cases are shown between Barrow, AK and Corpus Christi, TX on the timescale of minutes to hours. Similar variation patterns in the FW EZ are shown at both sites, providing evidence of the global nature of the atmospheric electric system. Furthermore, the seasonal-diurnal variability of FW at multiple sites shows similar distributions of the PG.

A series of ZSM-5 nanozeolites with hierarchical porosity were prepared by a seeding method and the addition of phenylaminopropyltrimethoxysilane (PATMOS) into the medial synthesis system. The influence of the amounts of PATMOS on the pore characteristics, crystallinity, morphology and acidity of the ZSM-5 zeolites were studied by XRD, N 2 -adsorption, 27 Al MAS NMR, SEM, TEM and NH 3 -TPD. The crystal size of the ZSM-5 zeolites could be adjusted in a certain range, and the mesopores were generated by introducing PATMOS. In addition, the catalytic performances of the hierarchical nanocrystalline ZSM-5 were investigated for methanol aromatisation (MTA). The hierarchical nanocrystalline ZSM-5 catalysts with a small crystal size and numerous mesopores exhibited high stability for the MTA reaction due to an enhanced mass transfer property and reduced diffusion limitations.

Carbon black (CB), multiwalled carbon nanotubes (MWNTs), reduced graphene oxide (rGO) are used as the cathode catalyst supports to investigate the effect on direct methanol fuel cell (DMFC) performance by using rotating disk electrode and fuel cell testing. The results of linear sweep voltammetry (LSV) and cyclic voltammetry (CV) show that the electrocatalytic activity sequence for oxygen reduction reaction (ORR) is Pt/rGO > Pt/MWNTs > Pt/C catalysts. The single cell tests results show that the maximum power densities of DMFC with Pt/C, Pt/MWNTs and Pt/rGO cathode catalysts are 74.0, 74.2 and 3.3 mW cm −2 , respectively. The experimental results indicate that the performance of DMFC is substantially influenced by the structures of cathode catalyst supports. The significant differences in DMFCs performance are due to the compression ratios and hydrophilic/hydrophobic properties of catalyst layers with different structures of carbon supports, which strongly affect electrochemical active sites and mass transport in cathode catalyst layers. Long-term testing of DMFCs indicates that Pt/MWNTs exhibits superior stability. Considering the factors of the power and lifetime comprehensively, MWNTs is optimal candidate among the three investigated carbon supports.

Background Omalizumab has demonstrated efficacy as an add-on therapy in Chinese patients with moderate-to-severe allergic asthma. This post-hoc analysis assessed the potential predictors for the efficacy of omalizumab in these patients. Methods A post-hoc analysis was performed on a Phase III, randomised, controlled study conducted in Chinese patients with moderate-to-severe persistent allergic asthma ( NCT01202903 ). We evaluated if levels of pre-treatment serum total immunoglobulin-E (IgE) and blood eosinophil (EOS), asthma severity, allergen profile, history of perennial allergic rhinitis (PAR), and free IgE level during omalizumab treatment were predictive of omalizumab's efficacy. Results This analysis included 608 patients (omalizumab, N = 306; placebo, N = 302). Improvements in forced expiratory volume in 1 s (FEV1), standardized Asthma Quality of Life Questionnaire (AQLQ), Asthma Control Questionnaire (ACQ), and Global Evaluation of Treatment Effectiveness (GETE) scores with omalizumab treatment compared with placebo were observed in patients with baseline IgE levels ≥76 IU/mL (irrespective of the EOS count). Relatively greater improvements with omalizumab treatment was also noted in patients with both moderate or severe allergic asthma (regardless of asthma severity), and patients sensitised to >3 allergens and with a history of PAR. All patients who were treated with omalizumab achieved free IgE levels below 50 ng/mL by Week 1. Similar clinical outcomes were observed in the subset of patients who achieved free IgE levels of Conclusions In Chinese patients with moderate-to-severe allergic asthma, baseline IgE and allergen profile (number/PAR history) are potential predictors of treatment response to omalizumab. Trial registration NCT01202903 ( www.clinicaltrials.gov ).

The chemical composition of the upper continental crust (UCC) dramatically changed from predominantly sodic to more potassic during the late Archean (3000–2500 Ma), although how this change occurred remains poorly constrained. The origins of Neoarchean potassic granites may provide clues for this crucial change, as their formation dominated the compositional transition of the UCC. In this study, we conducted high-precision Mg isotopic analyses of Neoarchean potassic granites (2558–2520 Ma) and tonalite–trondhjemite–granodiorites (TTGs; 2595–2574 Ma) from the North China Craton and statistical geochemistry in K2O/Na2O ratios of global Archean granitoids. Results show that these TTGs, with K2O/Na2O ratios of ~0.61 and δ26Mg values of −0.39‰ to −0.22‰, were generated from heterogeneous basaltic sources. In contrast, potassic granites yield two distinctive groups of δ26Mg values and can be subdivided into I- and S-types. The I-type granite has mantle-like δ26Mg values of −0.28‰ to −0.22‰ and weak enrichment in K2O (K2O/Na2O = 1.0–1.5), and was likely derived by partial melting of igneous sources. The S-type is characterized by much higher δ26Mg values of +0.60‰ to +0.91‰ and strong K2O enrichment (K2O/Na2O = 1.57–23.26), with geochemical characteristics suggesting derivation by partial melting of sediments. Based on the geochemical characteristics of the S-type potassic granites in this study, we sort the S-type granites out of 4066 Archean felsic igneous rocks worldwide. Their temporal distribution suggests that S-type potassic granites have appeared in the middle Archean (3500–3000 Ma) and became widespread in the late Archean (3000–2500 Ma), but were scarce in the early Archean (4000–3500 Ma). The onset of S-type granites indicates reworking of supracrustal rocks may have started since 3500 Ma. And widespread S-type potassic granites during 3000–2500 Ma play an important role for the high K2O/Na2O ratio of UCC at the end of Archean. A mass-balance calculation shows that 25.88 wt% I-type, 4.12 wt% S-type potassic granite and 70 wt% TTGs could increase the K2O/Na2O ratio of the UCC to ~0.83 which is the global average value for felsic rocks at the end-Archean. To increase K2O/Na2O of the Archean UCC, contributions made by I- and S-type potassic granites could probably reach 3:2, respectively. Consequently, the evolved crustal composition from predominantly sodic to potassic results from the synergy of re-working of igneous (unaltered) and sedimentary (weathered) rocks, by which the former contributed more quantitatively, while the latter contributed more efficiently.

We report the synthesis of boron-doped graphene by thermally annealing the mixture of graphene oxide and boric acid, and its usage as the support of Pt catalyst towards the methanol oxidation reaction. The composition, structure and morphology of boron-doped graphene and its supported Pt nanoparticles (Pt/BG) are characterized by transmission electron microscopy, inductively coupled plasma mass spectrometry, Raman spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. It is revealed that boron atoms are doped into graphene network in the form of BC 2 O and BCO 2 bonds, which lead to the increase in defect sites and facilitate the subsequent deposition of Pt nanoparticles. Therefore, the Pt/BG catalyst presents smaller particle size and narrower size distribution than the graphene supported Pt (Pt/G) catalyst. When evaluated as the electrocatalyst for the methanol oxidation reaction, the Pt/BG catalyst exhibits excellent electrochemical activity and stability demonstrated by cyclic voltammetry and chronoamperometry tests. The enhanced activity is mainly ascribed to the electronic interaction between boron-doped graphene and Pt nanoparticles, which lowers the d-band center of Pt and thus weakens the absorption of the poisoning intermediate CO. Our work provides an alternative approach of improving the reaction kinetics for the oxidation of small organic molecules.

The performance of gasoline direct injection (GDI) engine is simulated using the AVL-FIRE code. The effects of four piston shapes on mixture formation and combustion are compared and analyzed. For GDI engines with forward tumble and multihole high-pressure injector, a piston with flat top surface and pit is beneficial for the maintenance of in-cylinder turbulence intensity. Such structure aids in the formation of a combustible mixture around the spark plug at the time of ignition. A piston with a smoother top surface strengthens the turbulence kinetic energy at the time of ignition, thereby accelerating combustion and increasing in-cylinder temperature and pressure. The higher in-cylinder temperature and pressure promote NO emission, whereas soot emission decrease because of subsequent oxidation.

Catalyst supports are known to play important role in governing overall catalyst activity and durability. Here, a new type of SnO2–TiO2 solid solution (TixSn1-xO2) support was prepared via a solvothermal method with substitution of Ti4+ by Sn4+ in the TiO2 lattice. Furthermore, the TixSn1-xO2 was combined with conventional carbon black (Vulcan XC-72) to prepare a hybrid support (TixSn1-xO2–C) for depositing Pt nanoparticles. The ratios of Sn vs. Ti in the solid-solution and TixSn1-xO2 vs. XC-72 were systematically optimized in terms of their performance as supports for methanol oxidation. Compared to Pt/TiO2–C and commercial Pt/C catalysts, the best performing Pt/Ti0.9Sn0.1O2–C catalyst exhibited the highest activity, evidenced by methanol oxidation and CO stripping experiments. The well-dispersed Pt nanoparticles (2–3 nm) are mostly deposited on the boundaries of Ti0.9Sn0.1O2 and carbon blacks. Formation of the special triple junction structure can play an important role in improving Pt utilization with increased electrochemical active surface areas (ESA) of Pt. In addition, the enhanced activity for Pt supported on Ti0.9Sn0.1O2–C is due to high content of OH group on Ti0.9Sn0.1O2 along with the strengthened metal-supports interactions. Both promote the oxidation of poisoning CO absorbed on Pt active sites.

Ce 0.8 Sn 0.2 O 2− δ solid solution is fabricated using a simple one-step solvothermal method. The synthesized solid solution mixed with Vulcan XC-72 carbon black (denoted by Ce 0.8 Sn 0.2 O 2− δ –C) is employed as a co-catalytic support for Pt catalysts toward methanol electrooxidation. X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, N 2 adsorption/desorption and temperature programmed reduction (TPR) are used to characterize the properties of Ce 0.8 Sn 0.2 O 2− δ solid solution. The results show that Ce 0.8 Sn 0.2 O 2− δ possesses a high specific surface area, an enhanced conductivity and a high oxygen storage capacity (OSC). Pt catalysts grown around Ce 0.8 Sn 0.2 O 2− δ on carbon black form a special Pt–Ce 0.8 Sn 0.2 O 2− δ –C triple junction structure, and their electrocatalytic properties are investigated in detail by a series of electrochemical methods. As compared with Pt/CeO 2 –C and commercial Pt/C catalysts, Pt/Ce 0.8 Sn 0.2 O 2− δ –C catalyst exhibits superior electrocatalytic activity and long-term stability for methanol electrooxidation in acid media. The origin of the enhanced electroctatlytic properties for Pt/Ce 0.8 Sn 0.2 O 2− δ –C is closely related to the OSC of Ce 0.8 Sn 0.2 O 2− δ and the triple junction structure.

The effects of reformed exhaust gas recirculation (REGR) on combustion and emissions of dimethyl ether (DME) homogeneous charge compression ignition (HCCI) engines are studied by multi-dimensional CFD coupled with chemical kinetic model. The results show that REGR combing EGR and DME reformed gases (DRG) improves combustion and emissions. REGR can delay ignition time by both EGR and DRG, and makes main combustion closer to top dead center (TDC), which is beneficial to reducing compression negative work and broadening load range of HCCI engines. The interaction of DRG and EGR helps avoid too high pressure rise rate or low power performance when being applied independent of each other. HC, CO and NO x emissions can be controlled simultaneously by REGR. Both advantages of DRG and EGR are used to decrease the emissions of HCCI engines by REGR, while the disadvantages of high emissions are alleviated when one of them is applied.

The concept of pseudospectra was introduced by Trefethen during the 1990s and became a popular tool to explain the behavior of non-normal matrices. In this paper, we propose a fast algorithm for computing the pseudospectra of Toeplitz matrices by using fast Toeplitz QR factorization. Numerical experiments are given to illustrate the efficiency of the new algorithm.

The Copper-doped cobalt oxide films have been prepared onto titanium support by reactive DC magnetron sputtering. The deposits are characterized by X-ray diffraction (XRD), energy-dispersive spectrometry (EDS), Ultroviolet (UV) and scanning electron microscope (SEM). The electrochemical characteristics of deposits are explored by cyclic voltammetry (CV), linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS). The effect of copper content in the Cu–Co oxides on the surface morphology, electrochemical and crystallographic properties has been investigated. The introduction of Cu element makes the Cu–Co oxides deposit fine and further lead to high roughness of deposits, which is helpful for the oxides’ electrochemical performance. Based on the electrochemical determination, the binary oxide electrodes exhibit better catalysis activity than that of CuO and Co 3 O 4 electrodes for oxygen evolution reaction (OER). The increase OER activity has been attributed to the enlarged surface roughness and the new active sites of deposits, according to the results of EIS.

There are presently different types of air conditioning products in China such as room air conditioners, variable speed room air conditioners, unity air conditioners, multi-connected air-condition (heat pump) unit, chilled water air conditioning systems. For these air conditioning products, evaluation indexes have been created, respectively including energy efficiency ratio (EER), coefficient of performance (COP), seasonal energy efficiency ratio (SEER) and integrated part load value (IPLV), and their energy efficiency standards have been established. Based on thermodynamic perfectibility, this paper makes the compatible analysis of the energy efficiency and thermodynamic perfectibility gradient of energy efficiency standards for different air conditioning products. According to testing conditions of evaluation indexes, these air conditioning products are classified into two groups, the standard rating conditions group (EER, COP) and the variable working condition group (SEER, IPLV). The results show the thermodynamic perfectibility of different air conditioning products grade as the same level for energy efficiency standards in each group differ from one another. Besides, the average thermodynamic perfectibility gradient of energy efficiency levels for air conditioning product in the standard rating conditions group is basically the same, and that of variable speed room air conditioners and multi-connected air-condition (heat pump) unit are the highest and lowest, respectively.

In this paper, the blend membranes based on sulfonated poly(ether ether ketone) and sulfonated cyclodextrin as the proton conducting membranes for DMFCs usage are prepared and investigated. The incorporation of sulfonated cyclodextrin in SPEEK membranes is evaluated by the characteristic absorptions of FT-IR spectra. Thermal stability and micro-morphology of the blend membranes are determined by thermogravimetry analysis and scanning electron microscope tests. The properties of the blend membranes are investigated such as swelling behavior, methanol permeability and proton conduction as function of the fraction of sulfonated cyclodextrin. The methanol crossover could be suppressed by the incorporation of sulfonated cyclodextrin and the methanol permeability decreases when the methanol concentration increases from 2.5 M to 20 M. Proton conduction is also promoted by the introduction of sulfonated cyclodextrin and the proton conductivity increases with the increase of sulfonated cyclodextrin content. The calculated activation energy for proton conduction of the blend membranes is very low and the maximum value is 4.20 kJ mol−1, which is much lower than that of Nafion 115 (9.15 kJ mol−1, measured in our experiments). These data indicate that proton can transport easily through the blend membranes. The selectivity of the blend membranes, a compromise between proton conductivity and methanol permeability, is much higher than that of Nafion 115 at the sulfonated cyclodextrin content above 15 wt.%. The blend membranes with 15, 20, and 25 wt.% of sulfonated cyclodextrin are assembled in the practical DMFCs and their polarization curves with 2.5 M and 8.0 M methanol solution are determined, respectively. The membrane with 20 wt.% sulfonated cyclodextrin reaches the highest power density of 29.52 mW cm−2 at 120 mA cm−2 and 8.0 M methanol solution. These results suggest the potential usage of the SPEEK membranes incorporating with sulfonated cyclodextrin in DMFCs.

This paper describes the preparation of SiO2 stabilized Pt/C catalyst (SiO2/Pt/C) by the hydrolysis of alkoxysilane, and examines the possibility that the SiO2/Pt/C is used as a durable cathode catalyst for proton exchange membrane fuel cells (PEMFCs). TEM and XRD results revealed that the hydrolysis of alkoxysilane did not significantly change the morphology and crystalline structure of Pt particles. The SiO2/Pt/C catalyst exhibited higher durability than the Pt/C one, due to the facts that the silica layers covered were beneficial for reducing the Pt aggregation and dissolution as well as increasing the corrosion resistance of supports, although the benefit of silica covering was lower than the case of Pt/CNT catalyst. Also, it was observed that the activity of the SiO2/Pt/C catalyst for the oxygen reduction reaction was somewhat reduced compared to the Pt/C one after the silica covering. This reduction was partially due to the low oxygen kinetics as revealed by the rotating-disk-electrode measurement. Silica covering by hydrolysis of only 3-aminopropyl trimethoxysilane is able to achieve a good balance between the durability and activity, leading to SiO2/Pt/C as a promising cathode catalyst for PEMFCs.

Objective Unexplained weight loss is common in patients with chronic obstructive pulmonary disease (COPD). Because ghrelin plays an important role in energy homeostasis, this study investigated the plasma level of ghrelin in COPD. Methods Plasma ghrelin levels and levels of leptin, tumor necrosis factor-α, and C-reactive protein were measured in 29 patients with COPD and 17 healthy controls. Body composition was assessed with bioelectrical impedance analysis. Results Body mass index and percentage of body fat were lower in patients who had COPD than in healthy controls. Plasma ghrelin and leptin concentrations were significantly lower in patients who had COPD than in healthy controls (ghrelin: 0.25 ± 0.22 ng/mL versus 0.43 ± 0.24 ng/mL, P = 0.013; leptin: 1.77 ± 0.70 ng/mL versus 2.85 ± 0.96 ng/mL, P = 0.000). In contrast, tumor necrosis factor-α and C-reactive protein were significantly higher in those with COPD than in controls. Plasma ghrelin (log transformed) was positively correlated with body mass index and percentage of body fat in patients with COPD but negatively correlated in control subjects. Plasma ghrelin was negatively correlated with tumor necrosis factor-α and C-reactive protein in COPD. Conclusion Plasma ghrelin level was decreased in COPD and this is different from other weight-loss diseases. These data suggest that decreased ghrelin and other factors may contribute to alterations in metabolic status during inflammatory stress in this disease.

Catalytic production of hydrogen by steam reforming of methanol reaction has been developed on a series of co-precipitated Cu/ZrO2/Al2O3 catalysts at atmospheric pressure in a microreactor. Effects of catalyst composition, reaction temperature, H2O/CH3OH molar ratio and methanol space velocity on the performance of Cu/ZrO2/Al2O3 catalysts have been investigated. Cu/ZrO2/Al2O3 catalysts exhibited higher activity and stability as compared to Cu/Al2O3 catalyst. The catalyst containing 15 wt.% of ZrO2 was the most active one with a methanol conversion of 95.0 mol%, H2 selectivity of 99.9 mol% and the outlet CO concentration of 0.17 mol% at 250 °C. After 200 h of reaction, methanol conversion was still over 90.0 mol% with Cu/ZrO2/Al2O3 catalyst. XRD results showed that the addition of ZrO2 to Cu/Al2O3 catalysts not only greatly improved copper dispersion in the catalyst surface but also prevented copper crystallites from conglomeration or sintering.