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Hydrophobic and oleophobic materials have an important role in daily-life and industry. The hydrophobic and oleophobic property is mainly ascribed to the low surface energy materials and the roughness surface. The hydrophilicity and oleophobicity surface can be achieved by surface modification methods, such as electrodeposition, sol–gel process, chemical vapour deposition and spray deposition. In this paper, the properties of hydrophobic and oleophobic materials are introduced. The principles, characteristics and applications of surface modifications in hydrophobic and oleophobic materials are reviewed.

To establish an analysis method for the detection of 6 arsenic compounds [AsC, AsB, As（Ⅲ）, DMA, MMA and As（V）] in blood and urine by high-performance liquid chromatography-inductively coupled plasma-mass spectrometry （HPLC-ICP-MS）, and apply it to real cases.Triton was used to damage cells, and then EDTA·2Na·2H2O was used to complex arsenic compounds in cells, and sonication and protein deposition by acetonitrile were performed for sample pretreatment. With the mobile phase consisted of ammonium carbonate and ultrapure water, gradient elution was performed for obtaining the arsenic compounds in samples, which were analysed by ICP-MS with Hamilton PRP-X100 column.The limits of detection in blood were 1.66-10 ng/mL, while the lower limits of quantitation in blood ranged from 5 to 30 ng/mL. The limits of detection in urine were 0.5-10 ng/mL, while the lower limits of quantitation in urine were 5-30 ng/mL. The relative standard deviation of inter-day and intra-day precisions was less than 10%. This method had been successfully applied to 3 cases.This study has established an analysis method for detecting 6 common arsenic compounds in blood and urine, which can be used to detect the arsenic compounds in the blood and urine from arsenic poisoning cases as well as the patients under arsenic treatment.

The microstructures and tensile properties of electrodeposited nanocrystalline Ni (nc-Ni) with a broad grain size distribution after annealing at 150, 200 and 300°C for 500 s were investigated. The as deposited broad grain size distribution nc-Ni sample exhibited a moderate strength σUTS of ∼1107 MPa but a markedly enhanced ductility ϵTEF of ∼10%, compared with electrodeposited nc-Ni with a narrow grain size distribution. Annealing below 200°C increased the strength but caused a considerably reduction in tensile elongation. This behaviour is attributed to the grain boundary relaxation and the increased order of grain boundaries after annealing, which can make the grain boundary activities, such as the grain boundary sliding and grain rotations, more difficult. Further annealing at 300°C decreased both the yield strength and tensile elongation significantly due to significant grain growth.

In the present study, the room temperature mechanical properties of nanocrystalline Ni and Ni–75 wt-%Co alloy, prepared by pulse electrodeposition, were contrasted. Both higher strength and higher ductility were obtained for the Ni–75%Co alloy with a dual phase structure and an average grain size of 7·2 nm. By means of TEM observations of grain structures before and after tensile deformation for Ni and Ni–75%Co samples, a link between the ductility and the variation of stress induced grain growth during tensile deformation was established. Observations of TEM showed stress induced grain growth during tensile deformation, subjected to very high stresses and large strains, is very insignificant for the Ni–75%Co alloy in sharp contrast to the significant stress induced grain growth occurring in Ni. It was proposed that suppression of stress induced grain growth during tensile deformation can delay and even prohibit formation of shear banding plastic instability and thus enhances uniform strain leadin...

Ultrafine grained nickel (UFG Ni) and microcrystalline nickel (MC Ni) were fabricated on two types of substrates, i.e. the amorphous (Ni–P) and polycrystalline (stainless steel) substrates by pulse electrodeposition without additives. This study demonstrates that when inhibiting the epitaxial growth by first depositing a thin amorphous layer on the polycrystalline substrates, the grain size of the subsequent Ni deposit decreases dramatically from microscale to the UFG regime, which depends on the deposition conditions. Compared with MC Ni, which has an ultimate tensile strength σUTS of 397 MPa and an elongation to failure eTEF of 11·98%, UFG Ni with an average grain size of 120·72 nm exhibits an enhanced σUTS of 807 MPa and a comparable eTEF of 10·44%. The electrodeposited method used in this study provides an effective and low cost way to produce UFG materials with both high strength and ductility, which can meet the demands for practical application as structural materials.

In the present work, nanocrystalline Ni (nc-Ni) with a broad grain size distribution (BGSD) of 5-120 nm and an average grain size of 27.2 nm was prepared. The BGSD nc-Ni sample shows a similar strength and good ductility in comparison with electrodeposited nc-Ni with a narrow grain size distribution. The intracrystalline dislocation network was observed in the post-deformed microstructure confirming the conventional intracrystalline dislocation sliding mechanism in BGSD nc-Ni. The uniaxial tensile loading-unloading-loading deformation shows BGSD nc-Ni has the capability to store dislocations in the grain interior, which is very limited compared with that of coarse grained metals. For BGSD nc-Ni, the strain rate sensitivity of flow stress m enhances with decreasing strain rate. At the strain rate of 5 x 10(-6) s(-1), m was estimated to be 0.055. At the corresponding strain rate, the enhanced ductility along with the decreased strength was achievable, indicating activation of other deformation mechanisms, e. g. grain boundary sliding or diffusion.

Hydrogen storage capacity of various carbon materials, including activated carbon (AC), single-walled carbon nanohorn, single-walled carbon nanotubes, and graphitic carbon nanofibers, was investigated at 303 and 77 K, respectively. The results showed that hydrogen storage capacity of carbon materials was less than 1 wt% at 303 K, and a super activated carbon, Maxsorb, had the highest capacity (0.67 wt%). By lowering adsorption temperature to 77 K, hydrogen storage capacity of carbon materials increased significantly and Maxsorb could store a large amount of hydrogen (5.7 wt%) at a relatively low pressure of 3 MPa. Hydrogen storage capacity of carbon materials was proportional to their specific surface area and the volume of micropores, and the narrow micropores was preferred to adsorption of hydrogen, indicating that all carbon materials adsorbed hydrogen gas through physical adsorption on the surface.

Beta-arrestins (β-arrs) are initially known as negative regulators of G protein-coupled receptors (GPCRs). Recently, there is increasing evidence suggesting that β-arrs also serve as scaffolds and adapters that mediate distinct intracellular signal transduction initiated by GPCR activation. In the previous study, we have shown that metabotropic glutamate receptor 7 (mGluR7) and extracellular signal-regulated kinase 1 and 2 (ERK1/2) signaling may be involved in the developmental sevoflurane neurotoxicity. In the present study, we showed that activation of mGluR7 with a group III mGluRs orthosteric agonist LAP4 or an atypical mGluR7 allosteric agonist N,N'-bis(diphenylmethyl)-1,2-ethanediamine dihydrochloride (AMN082) significantly attenuated sevoflurane-induced neuronal apoptosis. Interestingly, this neuroprotective role of LAP4 could be partially reduced by β-arr1 small interfering RNA (siRNA) or β-arr2 siRNA transfection. In contrast, β-arr2 siRNA transfection alone abolished the effects of AMN082 on sevoflurane neurotoxicity. In addition, administration of LAP4 or AMN082 significantly enhanced Phospho-ERK1/2 in sevoflurane neurotoxicity, which could be abrogated by β-arr2 siRNA transfection, but not by β-arr1 siRNA transfection. Increased β-arr2-dependent Phospho-ERK1/2 signaling alleviated sevoflurane neurotoxicity by inhibiting bad phosphorylation. We also found that the neuroprotective role of AMN082 was completely reversed by ERK1/2 inhibitor 1,4-diamino-2,3-dicyano-1,4-bis[2-aminophenylthio]butadiene (U0126). Alternatively, treatment with U0126 partially suppressed the neuroprotective of LAP4, suggesting that other mechanisms may be implicated in this process. Further investigation indicated that, in the scenario of sevoflurane neurotoxicity, application of LAP4 (but not AMN082) increased the interaction of β-arrs with transcriptional factors CREB binding protein (CBP) and p300. LAP4 also enhanced the β-arr1-dependent H3 and H4 acetylation in sevoflurane neurotoxicity. For the behavior study, treatment with LAP4 or AMN082 significantly improved the emotional and spatial learning and memory disorders induced by postnatal sevoflurane exposure. These results suggested that β-arr1 and 2 may differently modulate mGluR7 signaling in developmental sevoflurane neurotoxicity. This study also reveals a β-arr-biased agonism at GPCRs (e.g. mGluR7).

The effects of hydrogen in the catalytic reforming of n-hexane, which consists of successive isomerization, cyclization, hydrogenolysis, and dehydrogenation, were examined using a palladium membran...

The behavior of sulfur transformation during rapid hydropyrolysis of coal was investigated using a pressurized, continuous free fall pyrolyzer under the conditions of temperature ranging from 923 to 1123 K and hydrogen pressure up to 5 MPa. The yields of sulfur converted to gas, tar and char were determined, together with the analyses of sulfur form distributions in coals and chars. The results showed that the decomposition of inorganic sulfur species was affected only by the temperature, while the increases in temperature and hydrogen pressure obviously enhanced the removal of organic sulfur from coal. The extent of organic sulfur removal was proportional to the coal conversion, depending on coal type. A significant retention of gaseous sulfur products by the organic matrix of the char was observed during hydropyrolysis of a Chinese coal above 1023 K, even under the pressurized hydrogen atmosphere. The kinetic analysis indicates that the rate of organic sulfur removal from coal was 0.2th-order with respect to the hydrogen pressure, and the activation energy for total sulfur removal and organic sulfur removal is 17–26 and 13–55 kJ/mol, respectively. The low activation energies suggest that the transformation and removal of sulfur from coal might be controlled by the diffusion and/or thermodynamic equilibrium during hydropyrolysis under the pressurized conditions.

The behavior of nitrogen evolution during rapid hydropyrolysis of coal has been investigated at temperatures ranging from 923 to 1123 K and hydrogen pressure up to 5 MPa using a continuous free fall pyrolyzer. Three coals have been tested in this study. The dominant nitrogen gaseous species is ammonia, together with a little amount of HCN because most of HCN is converted to NH 3 through secondary reactions. The results show that the evolution of nitrogen in coal is caused mainly by devolatilization at temperatures below 973 K, while the evolution of volatile nitrogen in char is accelerated with increasing temperature and hydrogen pressure. The mineral matter in coal act as catalysts to promote the evolution of volatile nitrogen in char to N 2 apparently at high temperatures of 1123 K, as found during pyrolysis of coal by Ohtsuka et al. A pseudo-first-order kinetic model was applied to the evolution of nitrogen in coal during rapid hydropyrolysis. The model shows the activation energy for the nitrogen evolution from coal is 36.6–58.6 kJ/mol while the rate of the nitrogen evolution depends on hydrogen pressure in the order of 0.16–0.24.

To establish an efficient process for hydrogenation of benzene to cyclohexane as one of the candidates for transportable, chemical hydrogen carriers, a combined scheme of water electrolysis and hydrogenation in the polymer electrolyte cell was proposed. A Rh–Pt electrode, which was found to be more active for electrochemical hydrogenation of benzene, was formed on a polymer electrolyte (Nafion, Du Pont) by means of soaking-reduction. Using an electrochemical cell, hydrogen pumping rate, electrochemical hydrogenation of benzene and water electrolysis were investigated at temperatures 25–70°C and atmospheric pressure, followed by combined electrochemical hydrogenation of benzene and water electrolysis. It became clear that benzene could be electrochemically hydrogenated on the cathode with hydrogen (proton), which was produced by water electrolysis at the anode and then pumped. The combined effects were recognized as a drop in decomposition voltage of water as well as a rise in current.

Methanol decomposition to carbon monoxide in a palladium membrane reactor (PMR) is presented, where a 1 wt % Pd/SiO2 catalyst and a Pd91Ru6In3 alloy membrane tube were employed. Experiments were carried out at relatively low temperatures, 220−250 °C, in a PMR mode as well as a conventional catalytic reactor (CCR) mode. A kinetic analysis for methanol conversion change in the CCR mode revealed that the overall reaction rate was controlled by the desorption process of the resultant carbon monoxide from the active sites of the catalyst surface. In the PMR mode it was shown that the selective separation of produced hydrogen from the reaction to the permeate side led to an increase in methanol conversion. Further, amounts of byproducts such as carbon dioxide, dimethyl ether, and methyl formate were found to be also influenced by the hydrogen separation.

The nascent surfaces of steel were formed by scratching mechanically under high vacuum conditions and adsorption and decomposition of formic acid on the surfaces were carried out at room temperature. The changes in partial pressures of the related compounds were monitored with a quadruple mass spectrometer. The results showed that the chemisorption rate of formic acid on the nascent surfaces was much higher than the formation rate of the reaction products, carbon dioxide and hydrogen. The analyses of adsorption and desorption activities of the compounds on (from) the nascent surfaces showed that the desorption activity of the products were as high as about 20 times the adsorption activity of formic acid. It is proposed that two types of sites might exist on the nascent surfaces. Although the active sites on the nascent surfaces could chemisorb formic acid molecules, only a portion could contribute to the decomposition of formic acid.

The hydrogenation of CO 2 to CH 4 was carried out using MgO-mixed catalysts of Ru, Ni, Fe or their combinations at temperatures ranging from 80 to 150°C under initial pressures of 100 Torr CO 2 and 500 Torr H 2 . The effect of the mechanical milling of catalysts on the reaction was investigated. It was found that (1) the yield of CH 4 strongly depended on the kind of catalysts; the highest yield was achieved with RuMgO catalyst and the lowest yield with NiFe catalyst. (2) Mechanochemically activated catalysts largely increased the production rate of CH 4 and considerably decreased the activation energy of the reaction from 74 kJ/mol to 41 kJ/mol for RuMgO catalyst.

Selective hydrogenation of phenol to cyclohexanone was attempted using a catalytic palladium membrane reactor (CPMR) at atmospheric pressure and temperatures ranging from 150 to 300°C. Four kinds of catalytic membranes made from palladium, Pd93Ni7, Pd93Ru7 and Pd77Ag23 were tested. The results showed the possibility of one-step production of cyclohexanone using the CPMR. Of all the membranes tested, pure palladium showed the highest activity for the production of cyclohexanone. The hydrogen permeating through the membranes was found to have higher reactivity than that pre-mixed into phenol.

Active hydrogen permeating through pure Pd, Pd 93 Ni 7 , Pd 77 Ru 7 , and Pd 77 Ag 23 membranes was applied to hydrogenation of acetylene at 373 K and atmospheric pressure. Two modes of the hydrogen-supplying route were employed, i.e. one permeating through the membranes (permeation mode) and the other previously mixed into the feed (premixed mode). The results showed that variation of H 2 flow rate leads to significant effects on the conversion of acetylene in the premixed mode but small effects in the permeation mode. This is because more activated hydrogen is directly available in the permeated mode while diffusion of hydrogen to the membrane surface and the following dissociation on it are required as the additional steps in the premixed mode

It is of increasing interest in systems biology to discover gene regulatory networks (GRNs) from time-series genomic data, i.e., to explore the interactions among a large number of genes and gene products over time. Currently, one common approach is based on Granger causality, which models the time-series genomic data as a vector autoregressive (VAR) process and estimates the GRNs from the VAR coefficient matrix. The main challenge for identification of VAR models is the high dimensionality of genes and limited number of time points, which results in statistically inefficient solution and high computational complexity. Therefore, fast and efficient variable selection techniques are highly desirable. In this paper, an introductory review of identification methods and variable selection techniques for VAR models in learning the GRNs will be presented. Furthermore, a dynamic VAR (DVAR) model, which accounts for dynamic GRNs changing with time during the experimental cycle, and its identification methods are introduced.

It is difficult to cope with the changes in power and polarization for partially polarized light. The light polarization will also affect the image quality, especially for imaging with large numerical aperture. A novel method of analyzing the power and the polarization state of partially polarized light is proposed in this paper. This method has a good intuitiveness and requires much smaller computation. An aplanatic lens system is simulated. Polarization effect caused is analyzed with this method. The results show that for the imaging light the intensity of TM polarized light relatively increases because of large numerical aperture, which will influence image contrast. Imaging in high refractive index medium can be used to improve this problem.