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Catalytic fast co-pyrolysis of biomass and plastic is an effective method to achieve high-quality bio-oil production. In this work, (Ni)-MCM-41 catalysts with different Ni loadings were prepared and characterized in detail by using a variety of advanced analytical techniques, and the effects on the catalytic performance were analyzed by micropyrolysis with gas chromatography mass spectrometry (Py-GC/MS) and thermogravimetry-Fourier transform infrared spectroscopy (TG-FTIR) methods. The results showed that an appropriate amount of Ni addition can effectively modulate the physicochemical properties of MCM-41. For a Ni loading of 25.1 wt % (Cat-C), the catalyst showed an optimal catalytic performance, a decrease in the proportion of oxygenated compounds in the product from 35.6 (MCM-41) to 13.4%, and an increase in the relative total amount of olefins plus aromatics from 62.2 (MCM-41) to 84.6%. The excellent catalytic performance of Cat-C can be ascribed to a balancing of its proper physical structural properties, appropriate acidity, strong metal–carrier interaction, high metal dispersion, and excellent compatibility balance between active and acidic sites.

The abnormally expressed peptidases in human tissues are associated with many kinds of cancers. Monitoring of endogenous peptidase activity could allow us for pathophysiology elucidation and early clinical diagnosis. Herein, we developed a general strategy for bioluminescence (BL) sensing of peptidase activity in vivo based on tumor-targeting probiotics. The probiotic that harbored a luciferase-encoding plasmid was used to target and colonize tumor and provide luciferase for BL imaging. The peptide-based probes Lc and GPc were applied to track leucine aminopeptidase (LAP) and dipeptidyl peptidase IV (DPPIV) activity, respectively, by simply adding l-leucine and Gly-Pro dipeptides at the N-terminus of d-cysteine, which were specifically controlled by peptidase cleavage and released free d-cysteine to conduct a subsequent click condensation reaction with 2-cyano-6-hydroxybenzothiazole (HCBT) to produce firefly luciferin in situ, giving rise to a strong BL signal. Neither gene modification of cells of interest nor complicated synthesis was required in this BL system. Encouraged by these advantages, we successfully used our probes to monitor LAP and DPPIV activities in vitro and in vivo, respectively. A good linearity between BL and peptidase was obtained in the concentration range of 2.5-40.0 mU/mL with a limit of detection (LOD) of 1.1 mU/mL (55 ng/mL) for LAP and 2.0-40.0 mU/mL with a LOD of 0.78 mU/mL (1.15 ng/mL) for DPPIV, respectively. Additionally, approximately 5-fold (LAP) and 10-fold (DPPIV) differences in the BL signal before and after treatment with a specific inhibitor were also obtained for in vivo BL imaging. All these results reflected the potential application value of our probes in BL sensing of peptidase activity. We envision that our strategy may be a useful approach for monitoring a wide range of peptidases in tumors, especially in primary tumors.

Ochratoxin A (OTA) is a very important mycotoxin. However, there are few studies on the removal of OTA in wine because of the great influence on product quality and difficulty in practical application. A nano-MgO-modified diatomite ceramic membrane (MCM) with a high positive charge was prepared and applied to remove OTA in wine. The isotherm adsorption between the positively charged membrane and OTA was in accordance with the Langmuir model, with a maximum adsorption capacity of 806 ng/g at 25 °C. All of the changes in adsorption enthalpy (ΔH), adsorption free energy (ΔG) and adsorption entropy (ΔS) were negative, which indicated that the combination of nano-MgO MCM and OTA was a spontaneous exothermic and nonspecific physical adsorption process. The concentrations of OTA in adsorption-treated wines were lower than 2 μg/kg, and the removal rates exceeded 92%. After OTA removal, the composition of wines was preserved to some extent.

Research on the determination of the product gas decomposed by sulfur hexafluoride (SF 6 ) in diverse discharge conditions is of considerable significance for the status evaluation of related electrical equipment. In this paper, the discharge experiment of SF 6 medium was conducted with a needle-plate electrode simulating the operating environment of gas insulated substation (GIS). The products were measured by gas chromatography, ion chromatography and other instruments, by which the appearance moment and content variation of HF, SO 2 F 2 , CF 4 , hydrolysable fluoride and other decompositions generated at 50 kV power frequency are illustrated. The formation of the product at lower energy conditions was investigated as a comparison by the discharge test at 14kV, and further experimental investigation was carried out with the electrode spacing of 0.2cm. This article also analyzed the impact of solid insulating medium (such as polyester film) on characteristic breakdown products by the discharge experiment involving solid insulating medium. The results indicated that HF was the first to be generated despite of the discharge energy, and the detected moment of SO 2 F 2 will be delayed with the decrease of discharge energy, as its concentration promoted when the discharge energy augmented. CF 4 was found in different discharge experiment, and a higher concentration of CF 4 was supposed to be related with the participating of solid insulating media. The experiment launched in this paper considered all forms of discharge fault in SF 6 electrical equipment in general and measured the consistence of breakdown gas of SF 6 correspondingly. The conclusion in this paper could contribute to the beforehand diagnosis and monitoring of sudden failures caused by discharges in SF 6 electrical equipment.

Because of its excellent insulation and arc extinguishing performance, Sulfur hexafluoride (SF 6 ) is widely used in electrical equipment such as gas insulated switchgear (GIS), circuit breakers, transformers. The detection of the components and contents of the decomposition products of SF 6 can provide an effective basis for the running state, abnormality or latent faults of SF 6 gas insulated electrical equipment in time. In order to ensure the accuracy and reliability of the results, this paper analyzed many cases in which SF 6 gas insulated electrical equipment were abnormal or broken-down in recent years, and made an in-depth study on multiple influence factors, such as sampling vessel material, sampling time, detection time, SF 6 decomposition products auto hydrolysis or be adsorbed by adsorbent and equipment structure. The results show that sampling by stainless steel bottles with fluorine coating, comprehensive investigation of the SF 6 gas decomposition products (such as SO 2 F 2 , SOF 2 ) that could characterize the fault, going to the scene as soon as possible or carrying out the inspection work through online device, fully considering the different detailed structure of electrical equipment are of important significance to improve the supervision level of SF 6 electrical equipment and achieve diagnosis and prediction when SF 6 electrical equipment gets fault.

A series of oxidation experiments were carried out on these novel γ/γ′-strengthened cobalt-based alloys of the systems Co–9Al–10W and Co–9Al–10W–0.02X (X = La, Ce, Dy, Y) at 900 °C. The appropriate amounts’ addition of rare earth elements leads to improved oxidation properties at 900 °C, especially La elements show the best oxidation resistance (129.008 mg/cm2). However, the base Co–9Al–10W alloy shows the worst oxidation performance (151.544 mg/cm2). Multilayer oxide layers formed during the oxidation process, the outer were mainly CoO and Co3O4 oxides, and the middle layer contained complex oxides (containing Co, Al, and W). The inner layer consists of little discontinuous oxides, included few Al2O3 oxides. There existed a different crack width and the base alloy had the widest crack. Moreover, there exists a phase transformation (γ/γ′ to γ/Co3W) at the interface between oxide film and substrate.

The isothermal oxidation experiments were carried out on several new γ/γ′-strengthened cobalt-base alloys Co–Al–W–4Cr–0.02X (X = La, Ce, Dy, Y) at 900 and 800 °C. Due to an appropriate content of additional elements, the change in the morphology occurred and it significantly improved the oxidation resistance compared with those without Cr, among which the one with La elements shows the best oxidation resistance. Multiple oxide layers are also formed during the oxidation process, with CoWO4 and CoAl2O4 phases in the outer layer, and Cr, Al, W, and Co (e.g., Cr2O3) in the middle layer. The inner layer consists of some Al2O3 oxides, while more protective Al2O3 oxide was formed, esp. at the temperature of 800 °C. Both Cr2O3 and Al2O3 oxides were effectively protective oxides, which can prevent the intrusion of oxygen into the alloy substrate. Moreover, a phase transformation (γ/γ′ to γ/Co3W) was observed at the interface between oxide layer and substrate.

Monitoring the humidity and pressure(density) of SF6 in electrical equipment has been used as the monitoring and management method for many years, however there is no obvious corresponding relationship between the data obtained by these methods and equipment faults. Now the detection of decomposition product of SF6 gas has been widely applied as a gradually popularized analysis method in the diagnosis of abnormal situation and fault of SF6 electrical equipment. However, factors such as sampling container material, sampling time, detection time, self-hydrolysis or adsorption by adsorbent of gas decomposition products and the structure of the equipment itself will affect the accuracy of the test data and the judgment on operating conditions of equipment. Through many cases dealing with faults of SF6 electrical equipment and the deep research on factors mentioned above, we have effectively improved the supervision level of SF6 electrical equipment. And it is proved that the detection of SF6 gas decomposition product is an effective method for monitoring and diagnosing SF6 electrical equipment, which is of great significance realizing the diagnosis and predicting SF6 electrical equipment fault.

The oxidation characteristics of boron particles, boron-A with the diameter of 2.545 µm and boron-B with the diameter of 10.638 µm, at low temperature (

The objective of this study was to isolate, identify, and investigate lactic acid bacteria (LAB) present in tomato pomace. In total, we isolated 108 LAB strains and subsequently identified 16 species (87.5 % homofermentative LAB). Among these, the isolation of Lactobacillus harbinensis, L. manihotivorans, L. helveticus, L. camelliae, L. pontis, L. amylovorus, L. hilgardii, L. panis, L. vaginalis, and L. rapi from vegetable samples is reported for the first time. This is the first report to describe the diversity and natural populations of LAB associated with tomato pomace. The physiological and biochemical properties of the isolates could provide a platform for the future design of LAB inoculants aimed at improving silage quality.

Pd-based catalysts modified with BaO as a promoter was prepared by impregnation method. The catalyst was characterized by H2-temperature-programmed reduction (H2-TPR) and X-ray photoelectron spectroscopy (XPS). The catalytic activity towards methanol showed that the BaO modification promoted the conversion of methanol. The light-off temperature (T50), complete conversion temperature (T90) and ΔT (T90-T50) for methanol oxidation are 100°C, 125°C and 25°C, respectively. The H2-TPR results showed that the addition of BaO increased palladium highly dispersed and promoted the reductive ability. It also enhanced the metal-support interaction and increased the electronic surroundings of Pd and Ce sites, which maintained Pd in a higher oxidized state and Ce4+ in Ce3+ state, consequently increased the activity for methanol oxidation according to XPS measurements.

Barium oxide was introduced to modify Palladium catalysts supported on CeO2–ZrO2-La2O3-Al2O3 (CZLA) by impregnation and co-precipitation. methods. Various techniques, including X-ray diffraction (XRD), H2-temperature-programmed reduction (H2-TPR) and X-ray photoelectron spectroscopy (XPS), were employed to characterize the physicochemical properties of BaO-modified Pd-only catalyst. Catalytic activity for methanol, CO, C3H8 and NO conversions showed that BaO-modified catalyst prepared by impregnation method exhibited the best performance for methanol, C3H8 and NO removals, while the catalyst prepared by co-precipitation method was in favor of CO oxidation. Combined with the results of XRD, H2-TPR and XPS, it is concluded that the co-existence of PdO and Pd-O-Ce active species by impregnation played an important role in the methanol, C3H8 and NO removals, while the higher dispersion of palladium and improved reducibility were mostly favorable to the CO oxidation. The conversion of NO was co-effected by tow active species and the formation of Ba2AlLaO5 mixed oxide.

SF 6 decomposition method has become an important tool for partial discharge (PD) detection and fault diagnosis, due to its anti-interference against electromagnetic noises and vibration. Actually, the gas density can affect the process of SF 6 decomposition by-products a lot. To study the influence of gas pressure, several experiments of SF 6 gas decomposition at different gas pressures were carried out. Based on the “three zone reaction model” as well as the theory of gas ionization, approximate mathematical expression was derived analytically to demonstrate the correlation between the gas pressure and root-mean-square production rates of SOF 2 and SO 2 . The experimental results indicated that the concentrations of SOF 2 , SO 2 , CO 2 , SO 2 F 2 declined with varying degrees of influence with increasing pressure under the same PD severity (sorted by degrees as SOF 2 >SO 2 >CO 2 >SO 2 F 2 ) and the rootmean-square production rates of SOF 2 and SO 2 significantly declined with increasing gas pressure while that of CO 2 and SO 2 F 2 have subtle changes. The fitting results with the proposed mathematical model verifies the correctness of the analytical expression, providing a promising way to fix the effects of gas pressure for the application of characteristic decompositions on GIS fault diagnosis.

Dangshansuli pear is one of crisp pears and has a non-climacteric respiratory pattern. Dangshansuli pear fruits were treated with 1 000 or 2 000 uL L-1 diphenylamine (DPA) for 1 min, or with 0.5 uL L-1 1-methylcyclopropene (1-MCP) for 12 h before cold storage at (2±0.5)°C for up to 210 d. Incidences of superficial scald and related physiological indexes were investigated during storage. The results showed that superficial scald occurred in control fruit with a rate of over 90% after 210 d at cold storage plus 10 d at room temperature. Treatments with 1 000 and 2 000 uL L-1 DPA and 0.5 uL L-11-MCP inhibited the accumulation of a-farnesene, conjugated trienes, total phenolic contents, and malondialdehyde (MDA) during storage. The treatments also decreased leakage of cell membrane and the activity of polyphenol oxidase (PPO) in the peel. These results indicate that 1-MCP and DPA treatments inhibit and postpone the occurrence of superficial scald of Dangshansuli pears remarkably in cold storage and post-storage shelf life, respectively, while the mechanisms were different. The results above may provide a theoretical evidence for the agriculture production.

Increasing environmental pollution caused by the volatile organic compounds due to their toxicity makes their removal imperative. So it is crucial to develop processes which can degrade these compounds effectively. The paper demonstrates that the photocatalytic activity of TiO2 toward the decomposition of gaseous benzene in a batch reactor can be greatly enhanced by loading TiO2 onto the surface of CexZr1−xO2 (x ≥ 0.25) using sol–gel technology. This research investigated the relationship between x amount and the photocatalytic activity of TiO2. The prepared photocatalysts were characterized by BET, XRD, UV–vis diffuse reflectance and XPS analyses. The specific surface area of photocatalyst decreases as x decreases. XRD results reveal the no peaks of titania were detected. Among the five catalysts prepared, only the binding energy values of Ti2p3/2 of TiO2/Ce0.5Zr0.5O2 shift toward lower value. The order of photocatalytic activity is TiO2/Ce0.5Zr0.5O2 > TiO2/Ce0.75Zr0.25O2 > TiO2/CeO2 ≈ TiO2/Ce0.25Zr0.75O2 > TiO2/ZrO2 ≈ TiO2. The mechanism role of Ceria–Zirconia mixed oxides in photocatalytic reaction was speculated.

Background Atrialfibrillation (AF) is associated with the activation of the renin-angiotensin-aldosterone system in the atria. It is not clear whether the expression of a mineralocorticoid receptor (MR), or 11β-hydroxysteroid dehydrogenase type 2 (11βHSD2), conferring aldosterone specificity to the MR, in patients with AF is altered. Hypothesis Patients with AF may be associated with increased expression of MR and 11βHSD2 in the atria. Methods Atrial tissue samples of 25 patients with rheumatic heart valve disease undergoing a valve replacement operation were examined. A total of 13 patients had chronic persistent AF (>6 mo) and 12 patients had no history of AF. The MR and 11βHSD2 expression were analyzed at the mRNA and protein level. The localization of MR and 11βHSD2 in atrial tissue was performed using specific immunohistochemistry staining. Results The results of real-time quantitative polymerase chain reaction (PCR) showed that AF groups, in comparison with sinus rhythm, had a higher mRNA expression level of MR or 11βHSD2 (all P < 0.01). Both the MR and 11βHSD2 protein expression level in atrial tissue were also significantly increased in patients with AF compared with patients with sinus rhythm (P < 0.05 or P < 0.01). The immunohistochemical staining of MR or 11βHSD2 demonstrated that MR and 11βHSD2 predominately located in the cytoplasm of myocardial cells in the atrium and the intensity and density of immunostaining appeared to be increased in the atria of patients with AF compared to those without AF. Conclusions Increasing expression of MR and 11βHSD2 in the atria during AF is one of the molecular mechanisms for development of atrial interstitial fibrosis in patients with AF. These findings may have an important impact on the treatment of AF with aldosterone antagonists. Copyright © 2010 Wiley Periodicals, Inc.

It has been found that the photocatalytic activity of TiO2 toward the decomposition of gaseous benzene can be greatly enhanced by loading TiO2 on the surface of SrAl2O4: Eu2+, Dy3+ using sol–gel technology. The prepared photocatalyst was characterized by BET, XRD, and XPS analyses. XRD results reveal that the peaks of titania in either rutile or anatase form are not detected by XRD in the 2θ region from 20° to 50°. The binding energy values of Ti 2p of pure TiO2 are 458.90 and 464.60 eV, while for TiO2/SrAl2O4: Eu2+, Dy3+, the binding energy values of Ti 2p are 458.50 and 464.20 eV. The results indicate that the optimum loading of TiO2 is 1 wt% and TiO2/SrAl2O4: Eu2+, Dy3+ (1 wt%) demonstrates 1.4 times the photocatalytic activity of that of pure TiO2, but the underlying mechanism of SrAl2O4: Eu2+, Dy3+ in the photocatalytic reaction remains to be unraveled.

TiO2 was prepared by sol–gel method using tetrabutyl titanate as precursor. TiO2 was loaded on Bi12TiO20. The photocatalyst with different TiO2 loading was calcined at 723 K. The photocatalytic activity of decomposition gaseous benzene was investigated in a batch reactor. The prepared photocatalyst was characterized by UV–vis diffuse reflectance. The result showed that TiO2/Bi12TiO20 absorbed much more ultraviolet light than TiO2 in the ultraviolet light region and showed red shift. The results indicated that the prepared photocatalyst can greatly promote the photocatalytic activity. The 2.0% TiO2/Bi12TiO20 system exhibited the highest photocatalytic activity.

Based on the SF6 decomposition device, this article has constructed two typical physical models of insulation defects and then used gas chromatography (GC) instrument to analyze the decomposed components of SF6 under the two kinds of partial discharge (PD) defects. Preliminary tests show that SOF2 is the main product of SF6 decomposition under both the two kinds of defects, the amount of SOF2 increases significantly with the extension of discharge time and that the gas production rates of SOF2 are apparently different under the two different kinds of defects.

Increasing environmental pollution caused by the volatile organic compounds due to their toxicity is a matter of great concern. So it is crucial to develop processes which can destroy these compounds effectively. It has been found that the photocatalytic activity of TiO(2) towards the decomposition of gaseous benzene can be greatly enhanced by loading Pd on the surface of TiO(2). The results show that the optimum palladium loading is 0.25wt.%. The prepared photocatalysts were characterized by XRD, UV-vis diffuse reflectance and XPS. XRD results indicate that no peaks of Pd are detected in the 2theta region from 10 degrees to 90 degrees . Pd/TiO(2) absorbs much more light than TiO(2) in the visible light region. The XPS spectrum shows that there are Ti, O, C and Pd elements on the surface of the Pd/TiO(2), the binding energy values of Ti2p of 0.25%Pd/TiO(2) transfer to a lower value. In addition, the photocatalytic performance of 0.25%Pd/TiO(2) was investigated, the result illustrates that 0.25%Pd/TiO(2) demonstrates 2.32 times the photocatalytic activity of pure TiO(2). The reason of promotion of photocatalytic performance was discussed.

A series of CeO(2)-ZrO(2) mixed oxides were prepared using coprecipitation method and characterized by BET, oxygen storage capacity (OSC), X-ray diffraction (XRD) and H(2)-temperature-programmed reduction (H(2)-TPR). The catalytic activities toward toluene combustion were investigated in a micro-reactor. The results demonstrate that the catalytic activity of Pt/gamma-Al(2)O(3)/Ce(0.50)Zr(0.50)O(2) monolithic catalyst can be greatly improved by doping metal into Ce(0.50)Zr(0.50)O(2). When doping Y and Mn into Ce(0.50)Zr(0.50)O(2) simultaneously, the catalyst Pt/gamma-Al(2)O(3)/Ce(0.40)Zr(0.40)Y(0.10)Mn(0.10)O(X) shows the highest activity. The T(10) (the temperature of 10% toluene conversion) and the complete conversion temperature (the temperature of 90% toluene conversion) of toluene are 443 and 489K, respectively. Gas hourly space velocity (GHSV) results show that the prepared catalyst can be applied in a wide range of GHSV (from 12,000 to 20,000h(-1)). The catalyst prepared shows great potential for practical application.