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For efficient thermal management in hypersonic aircraft, a series of highly stable macroinitiator/platinum/hydrocarbon nanofluids with great energy absorption capacity were designed in this work. Pt nanoparticles capped by hydrophobic hyperbranched polyglycerol (HMS) with average sizes of 1.2 nm and high dispersibility in hydrocarbons were synthesized through a facile phase transfer method and named as Pt@HMS. Nanofluids consisting of methylcyclohexane and Pt nanoparticles (MCH + Pt@HMS) presented admirable stability in the 180-day storage. On a simulated cooling channel of aircraft, the cracking performance and the energy absorption capacity of MCH + Pt@HMS were promoted significantly. At 650 °C, the heat sink of MCH + Pt@HMS reached 2.39 MJ/kg with an increase of 20.7% compared to thermal cracking. Larger macroinitiators HMS were beneficial. To acquire the same heat sink of 2.20 MJ/kg, the temperature can be lowered from 675 °C to 664 °C, 653 °C and 638 °C for the MCH + Pt@HMS with macroinitiator molecular weights of 3 k, 5 k and 13 k, respectively. The enhancements were ascribed to the synergistic catalysis of Pt@HMS. Endothermic reactions generating hydrogen and unsaturated hydrocarbons with higher enthalpies of formation were preferred for the cracking of MCH + Pt@HMS. Highly stable macroinitiator/platinum/hydrocarbon nanofluids are potential alternatives with great cracking performance and energy absorption capacity for efficient thermal management in hypersonic aircraft.

To accelerate the thermal cracking of hydrocarbon fuels and improve the cooling capacity for aircraft heat exchangers, cetyl-hyperbranched polyethyleneimine (CHPEI) synthesized from the modification of hyperbranched polyethyleneimine (HPEI) with a lipophilic alkyl chain was used as a novel macroinitiator. The pyrolysis performances under supercritical conditions (4.0 MPa, and 600–700 °C) of Jet propellant-10 (JP-10 or exo-tricyclo[5.2.1.02.6]decane) with CHPEI and the monomer triethylamine were compared in an electrically heated alloy tube. Both types of initiators with C-N bonds can promote the thermal cracking of JP-10, while CHPEI with a large molecular weight shows a similar crack-promoting effect to that of triethylamine with adding only one-tenth of the amount of the latter. As a typical example, the addition of 0.20 wt% CHPEI increased the conversion rate of JP-10 from 16.4% to 33.9%, and the corresponding heat sink was improved from 1.96 MJ/kg to 2.18 MJ/kg at 675 °C. On the basis of investigations on the intermediate species from different decomposition pathways of JP-10, it is proved that CHPEI accelerates the thermal cracking of JP-10 by generating lots of free radicals to participate in the H-abstraction reaction of JP-10. These efforts demonstrate that the macroinitiator CHPEI displays a great promise in hydrocarbon fuels for hypersonic applications.

The thermal stability of n-nonane and n-undecane, as the model endothermic hydrocarbon fuels, was evaluated by determining the content change of produced aromatics during the thermal cracking process. The 1H nuclear magnetic resonance spectroscopy (1H NMR), along with the high-performance liquid chromatography (HPLC) and the gas chromatography/mass spectrometry (GC/MS) analyses, is mainly considered to follow the formation of aromatics in the liquid cracking residues of the n-alkanes. The results of the aromatic contents obtained from these three analytical methods show satisfactory agreements. The 1H NMR method also gives the olefin content and the branching index of the liquid residues. The changes of the aromatics, olefins and branching index against the temperature directly reflect the thermal stability of the n-alkanes. Based on the results from 1H NMR, HPLC and GC/MS, a scheme of the formation of aromatics from the thermal cracking of n-alkanes is discussed.

Densities, viscosities, and refractive indices have been measured for the binary system of tricyclo[5.2.1.02.6]decane with cyclohexane, methylcyclohexane, ethylcyclohexane, butylcyclohexane, or 1,2,4-trimethylcyclohexane at temperatures T = (293.15 to 318.15 K) and pressure p = 0.1 MPa. The excess molar volumes (VmE), the viscosity deviations (Δη), and the refractive index deviations (ΔnD) are then calculated. The changes of VmE and Δη with the composition are fitted to the Redlich–Kister equation. The values of density, viscosity, and refractive index increase continuously with the increase of mole fraction of tricyclo[5.2.1.02.6]decane and decrease with the rise of temperature. The VmE and Δη are all negative over the whole composition range for these five binary systems. The changes of VmE and Δη are discussed from the points of view of molecular interactions in the binary systems.

Density, viscosity, flash point and refractive index for binary mixtures of cis-decalin or trans-decalin with nonane, decane, and undecane have been determined at pressure p = 0.1 MPa and different temperatures ranging from (293.15 to 323.15) K. The calculated excess molar volumes give negative values over the whole composition range for these binary systems. With the increase of mole fraction of decalin, the values of viscosity and refractive index increase continuously. The viscosity deviation and refractive index deviation are calculated, showing negative from the corresponding linear additive values. A small additional amount of the component with lower flash point leads to marked changes of flash point values of these binary mixtures.

This article investigates how banks build competitive advantage through relationship banking. Using a grounded theory approach, 29 interviews were conducted with relationship managers and corporate banking directors in 21 case banks from 2004 to 2008. Grounded theory models were developed to illustrate the value creation process in relationship banking. It was found that long-term bank–corporate relationships were established through trust-based personal communications. In the case, banks customer information and knowledge advantages were created. Risk-adjusted returns on assets were used to measure customer relationship performance, and relationship managers were rewarded accordingly. The interviewees thought that bank performance could be improved by managing customer credit risk and identifying cross-selling opportunities. This study starts to open up the ‘black box’ of how banks create shareholder value through relationship banking, provides a picture of relationship banking as a social phenomenon, and supplies some theoretical and managerial implications. The article also links the literature relevant to relationship banking from different disciplines. This is a new way of looking at the relationship banking phenomenon and relevant literature in an integrated manner.

Densities, viscosities, and refractive indices are investigated for binary mixtures of 1,2,3,4-tetrahydronaphthalene with several n-alkanes, namely, octane, nonane, and decane, at different temperatures (293.15 K, 298.15 K, 303.15 K, and 313.15 K) and atmospheric pressure. The values of density (ρ) of the compounds were used to compute excess molar volume (VmE) of the solution. The refractive indices of these binary systems were also determined over the whole concentration range at 293.15 K and 303.15 K.

A total of 10 new N-alkyl piperazinium-based ionic liquids (ILs) have been prepared, and they are used as extractants for removing aromatics from three kinds of hydrocarbon fuels. A total of 3 ILs,...

A novel ionic liquid N-ethyl piperazinium propionate, [NEPP], was prepared, and the densities and viscosities for the binary mixtures of [NEPP] with methanol, ethanol, n-propanol, and n-butanol were measured over the whole concentration range at (298.15, 303.15, 308.15, and 313.15) K and 0.1 MPa. The data of the excess molar volume, VmE, were calculated and fitted with the Redlich–Kister type polynomial equation. The values of VmE of the investigated systems are all negative, indicating that the ion–dipole interactions play important roles between the molecules of the ionic liquid and the alcohols.

A novel boron based electrolyte system based on reaction of tri(3,5-dimethylphenyl)borane (Mes3B) and PhMgCl in THF solution is proposed for the potential application in rechargeable magnesium battery. The optimized composition of Mes3B-(PhMgCl)2/THF electrolyte solution presents high ionic conductivity(ca. 2×10−3 S/cm in 0.5 M solution) at room temperature, excellent Mg deposition reversibility as well as the highest anodic potential to date (3.5 V vs. Mg RE). The initial results indicate that the high-performance of the Mes3B–(PhMgCl)2 electrolyte might be attributed to non-covalent interactions arising from the excess amount of Grignard reagent PhMgCl. This study opens the door to the development of boron based electrolyte chemistry for high-energy rechargeable Mg batteries. Keywords: Boron based electrolyte, Reversible Mg deposition and dissolution, Anodic stability, Rechargeable magnesium battery

Densities and viscosities were determined over the whole composition range for the binary mixtures of exo-tetrahydrodicyclopentadiene with n-nonane, n-dodecane, or n-tridecane at different temperatures (293.15, 298.15, 303.15, and 313.15) K and atmospheric pressure. The excess molar volumes VmE for the mixtures were calculated from the experimental data. The refractive index and surface tension of the systems were also measured for temperatures of (293.15 and 303.15) K.

Measurement on bubble-point vapor pressure, density and viscosity at several temperatures for binary mixtures tricycle [5.2.1.02.6] decane (JP-10), a high density fuel, and methylcyclohexane (MCH) were carried out. The correlation between vapor pressures and equilibrium temperatures of each mixture was performed and the Antoine equation parameters were given correspondingly. The experimental VLE data were correlated with the Wilson model. From the density and viscosity data, excess volume, V m E , and viscosity deviation, Δη, for the binary mixtures were calculated and fitted with the Redlich–Kister equation. The viscosities correlated with several semi-empirical equations were also performed. The excess molar volumes and the viscosity deviations are negative over the entire composition range.

本文确定了关系银行和业务拓展中的战略概念和实用技术，以及如何提高客户价值，以及如何衡量关系银行的业绩，并将其与客户经理的薪酬挂钩。采用扎根理论来收集和分析数据。对11家案例银行的关系经理和公司银行董事进行了25次访谈，并使用案例银行的定量数据来支持这些观点。。研究发现，顾客关系被视为一项有价值的资产。 通过内部调查评估关系导向和客户关注，制定客户关系管理目标，并提出行动建议，提高客户对案例银行的价值。在这个案例中，银行通过多个客户接触点收集客户信息并进行整合和分析。积累客户知识，建立可持续的竞争优势。顾客感知和顾客忠诚度由外部衡量。客户价值和风险调整资产回报率(RAROA)被用来衡量关系银行的业绩，并相应地奖励关系经理。受访者认为，在这种动态学习过程中，关系银行绩效可以得到改善。

Densities and viscosities of exo-tetrahydrodicyclopentadiene + n-undecane and exo-tetrahydrodicyclopentadiene + n-tetradecane were measured at different temperatures of (293.15, 298.15, 303.15, and...

The catalytic cracking of a high density hydrocarbon fuel, tricyclo [5.2.1.0 2.6 ] decane (JP-10) over HZSM-5 molecular sieves with different Si/Al mole ratios of 25, 38, and 50 was investigated at the temperature range from 773 to 873 K. Compared with the thermal cracking and the catalytic cracking over ZSM-5, conversions of JP-10 from the catalytic cracking over HZSM-5 molecular sieves at the same temperature were evidently heightened. The predominant hydrocarbon products from the catalytic cracking, checked at room temperature and atmospheric pressure, were methane, ethane, ethene, propane and propylene in the gaseous phase and benzene, indene, naphthalene and their homologues in the liquid phase. The contents of ethane, propane and propene decrease with increasing Si/Al mole ratio of a catalyst while those of methane and ethene increase simultaneously with the increase of Si/Al mole ratio of HZSM-5. The contents of the main components in the liquid products produced on the catalyst surface at a given temperature also decreased with the increase of Si/Al mole ratio. To keep high yields of alkenes, the HZSM-5 catalyst with high Si/Al mole ratio could be chosen.

Previous estimates of the global burden of disease for children have not included much information from China, leading to a large gap in data. We identified the main causes of deaths in neonates (1 month), postneonatal infants (1-11 months), and children (5 years) in China using information that was available to the public.The Child Health Epidemiology Reference Group in collaboration with colleagues from Peking University systematically searched Chinese databases that were available to the public. Information was obtained from the Chinese Ministry of Health and Bureau of Statistics websites, Chinese National Knowledge Infrastructure database, and Chinese Health Statistics yearbooks for 1990-2008. We also obtained information from 206 high-quality community-based longitudinal studies of different causes of deaths in children (5 years) that were written in the Chinese language. A statistical model was developed to estimate the total number of deaths in children according to provinces, age groups, and main causes.During 1990-2008, the mortality rates in neonates, postneonatal infants, and children were reduced by 70% (from 34.0 to 10.2 per 1000 livebirths), 72% (from 53.5 to 14.9 per 1000 livebirths), and 71% (from 64.6 to 18.5 per 1000 livebirths), respectively, meeting the targets set in the Millennium Development Goal 4. The leading causes of deaths in 2008 were pneumonia, birth asphyxia, and preterm birth complications, each accounting for 15-17% of all deaths. Congenital abnormalities and accidents increased in importance during this period, contributing to 11% and 10% of child deaths, respectively. Sudden infant death syndrome contributed to 5% of deaths in children.Publically available Chinese databases contain much important information that has been underused in the estimation of global and regional burden of disease. On the basis of trends, preterm birth complications are expected to become the leading cause of child mortality in China, whereas deaths from congenital abnormalities, accidents, and sudden infant death syndrome are predicted to continue increasing in importance in the long term.BillMelinda Gates Foundation.

Self-assembled silver nanoparticles with an average diameter of 5 nm have been successfully fabricated by reduction of Ag+ with ascorbic acid in the mixture of water, alkylamine, and oleic acid. Thermogravimetry (TG), differential scanning calorimetry (DSC), and contact angle measurements indicate that oleic acid molecules are well capped on the silver nanoparticles. The effects of temperature and reaction-medium pH on the morphology and composition of the silver nanoparticles are discussed. A decrease in pH leads to a tendency to produce silver nanorods and nanospheres. The temperature can affect the thickness of the organic layer on the surfaces of the silver nanoparticles. The stabilities of the silver nanoparticles in the nanofluids were monitored at different temperatures. Thermal conductivity enhancements were determined in kerosene-based nanofluids with the prepared silver nanoparticles. The surface-capped silver nanoparticles exhibited excellent dispersity in kerosene and conventional organic solv...

Densities and viscosities of exo-tetrahydrodicyclopentadiene + n-butanol and exo-tetrahydrodicyclopentadiene + n-pentanol were investigated over the whole composition range at several temperatures, (293.15, 298.15, 303.15, and 313.15) K, and atmospheric pressure. The excess molar volumes VmE for the mixtures were calculated based on these experimental data. The calculated quantities of VmE were fitted to the Redlich−Kister type polynomial equation, and the regression coefficients and the standard deviations of the fits were given. Several semiempirical equations were used to correlate the viscosity data, and the double-parameter McAllister equation gives satisfactory results.

Thermal cracking reactions of a kerosene-based aviation fuel were carried out in a constant-volume reactor, and the kinetics were investigated at different temperatures from 663 to 703 K. The gaseous and liquid products collected from the efflux cooled to room temperature at atmospheric pressure were determined by gas chromatography and gas chromatography−mass spectrometry. The major hydrocarbon components in the gaseous phase were methane, ethane, ethene, propane, and propene; methane had the highest content among them. In the liquid effluence, the contents of components with carbon atom number higher than C11 decreased while those with lower carbon atom number clearly increased with the temperature or reaction time increasing. The gas yield ratios increased with the reaction temperature or time increasing. The thermal cracking kinetic process was correlated well by the pseudo first-order kinetic equation. The correlation followed that the rate constants were in the range 0.163 × 10−2 h−1 at 663 K to 2.8...

Coking of three model compounds of hydrocarbon fuel—n-heptane, cyclohexane, and tricyclo[5.2.1.02.6]decane (JP-10)—during their thermal cracking processes under supercritical condition (873.15 K, 4.1 MPa) has been investigated. The product distributions of the thermal cracking are analyzed by gas chromatography−mass spectrometry (GC-MS). The morphology and microstructures of the cokes are characterized by the techniques of scanning electron microscopy (SEM), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). The results show that chemical structures play important roles in the thermal stability and coking property of the fuels. The thermal cracking conversion of n-heptane is highest, and the coke yield of JP-10 is highest under the same conditions. It is interestingly observed that the morphologies of the cokes produced from the thermal cracking of three fuels are quite different, which from n-heptane, cyclohexane, and JP-10 are in the forms of ca...

Endothermic hydrocarbon fuel can work as a coolant to disperse the heat generated by the surface and engine of hypersonic aircraft, due to its endothermic pyrolysis reaction under supercritical conditions. Herein the cracking of the hydrocarbon fuel ZH-100 in a continuous tubular reactor under four pressures (0.1, 1.5, 2.5 and 3.5 MPa) are studied. It was found that the conversion and the yield of gas product are lowest at the lowest pressure (0.1 MPa), the maximum value appears at 1.5 MPa, and the values at 2.5 and 3.5 MPa are intermediate and variable in order under different conditions. Methane and hydrogen are the most abundant components at atmospheric pressure and low temperatures. The light components in liquid product systems consist of numerous small alkenes, and the content of the light components can be promoted by increased temperature and pressure.

The density, viscosity, and vapor pressure for binary mixtures of tricyclo [5.2.1.02.6] decane (JP-10), a high-energy density hydrocarbon fuel, with diethyl carbonate are presented. Excess volume, VmE, and viscosity deviation, Δη, for the binary mixtures have been calculated. Positive values of VmE, negative values of Δη, and positive deviations from Raoult’s law for the vapor pressures are observed. The deviation results are discussed in terms of the changes of molecular interactions in the mixtures, and they are fitted with the Redlich−Kister equation. The viscosities have also been correlated with several semiempirical equations. These physical property data and calculations provide valuable information on the development and application of new high-energy density hydrocarbon fuels.

The transesterification of sunflower seed oil was carried out in supercritical ethanol without using any catalyst to produce biodiesel. In the present work, methylcyclohexane was added to enhance the vapor pressure of biodiesel. The vapor pressures of mixtures of biodiesel + methylcyclohexane as a function of temperature were measured by comparative ebulliometry with an inclined ebulliometer. The vapor pressures versus composition at different temperatures were obtained. Experimental data of vapor pressures and equilibrium temperatures were correlated by the Antoine equation. A mathematical model was used to predict the flash point of the pseudo binary mixtures. With the regular solution theory, the predictive flash point displays agreement with the experimental data obtained by closed cup test.

Vapor pressures and flash points for several mixtures of an aviation fuel with dimethyl carbonate (DMC) or diethyl carbonate (DEC) have been measured, respectively, over the entire composition range. Correlation between the experimental vapor pressures and the equilibrium temperatures by the Antoine equation is performed for each mixture. The bubble-point lines of pressure versus composition at different temperatures and those of temperature versus composition at different pressures are then obtained from the Antoine correlations. It is found that DMC and DEC are the oxygenated hydrocarbon additives that can adjust effectively the volatility and flash point of the aviation fuel. The correlation of the flash points with the vapor pressure data for the pseudo-binary mixtures of the fuel and DMC or DEC gives satisfactory results.

Vapor pressures for mixtures of a hydrocarbon fuel with ethylene glycol dimethyl ether (EGDME) and diethylene glycol dimethyl ether (DEGDME) were measured by comparative ebulliometry with inclined ebulliometers. Experimental data of vapor pressures and equilibrium temperatures for each mixture were correlated by the Antoine equation. The pseudo-binary vapor−liquid equilibrium (VLE) data were calculated with a non-random two liquid (NRTL) model. Prediction of the vapor pressures for the hydrocarbon fuel from the American Petroleum Institute (API) equations gave relatively satisfactory results. Furthermore, thermal conductivities for the pseudo-binary systems were measured at 273.15 and 298.15 K by means of a relative transient calorimeter. The data were compared to those calculated from the Jamieson equation. These results could provide important information on the development of oxygenate-blended fuels.

Thermal cracking of a high density hydrocarbon fuel, JP-10 (exo-tetrahydrodicyclopentadiene), was studied on a batch reactor under different pressures. The effluent was cooled and collected at room temperature and atmospheric pressure. The gaseous and liquid components were quantitatively determined by gas chromatography and gas chromatography−mass spectrometry, respectively. The conversion of JP-10 has relatively low value at atmospheric pressure and increases under pressure. With an increase of the pressure, the relative content of ethene or propene decreases and that of methane, ethane, or propane increases simultaneously. In the liquid products, cyclopentane, cyclopentene, 1,3-cyclopentadiene, and cis-bicyclo[3.3.0]oct-2-ene are found to be major components. Substituted cyclopentene, benzene, toluene, and naphthalene are also observed under high pressures and temperatures. A probable mechanism of the thermal cracking of JP-10 is proposed to explain the product distribution. The process of isomerizatio...

The enhanced autoxidation experiments of hydrocarbon fuels were performed simultaneously. The concentration of hydroperoxides in each fuel oxidized at temperatures from 120 to 180 °C was effectively quantified by measuring the absorption spectra of the iodine–starch solutions using ultraviolet–visible spectrometry. It can be observed that the hydroperoxide concentration increases, passes through a maximum value and then decreases to a low steady state at each temperature with the oxidation time going. The maximum values under various oxidation temperatures appear at obviously different times. The higher the temperature is, the earlier the maximum value of hydroperoxide concentration appears and the lower value it has. The thermal-oxidation stabilities for these fuels under different conditions are compared by the ultraviolet–visible spectrometry measurements and the infrared spectra. The results verify that the hydroperoxides, as the main intermediates, can transform themselves into various oxygenated species and that the hydroperoxide concentrations convey information concerning the thermal-oxidation stability of a particular fuel.

Diurnal variations of gas exchange, chlorophyll a fluorescence and some related biochemical characteristics in sun-acclimated mature citrus leaves of mist-sprayed (treatment) and unsprayed (control) trees were compared on sunny days during summer to identify the environmental and physiological factors limiting carbon gain in citrus tree canopies. At midday, net photosynthesis and maximal photochemical efficiency of photosystem II (Fv/Fm) in citrus leaves decreased significantly under control conditions, but the decrease was mitigated by mist spraying. Although the content of malondialdehyde, hydrogen peroxide and activities of antioxidant enzymes increased at midday in both mist-sprayed and control leaves, they were much higher in control leaves than in mist-sprayed leaves. The level of D1 protein decreased significantly in control leaves at midday and then was partly recovered later, while that in treated leaves changed to a much lesser extent because of alleviation of photoinhibition by mist spraying. Both the fast and the slow phases of millisecond-delayed light emissions in treated citrus leaves were higher than those in control leaves, indicating that mist spraying protects the normal operation of the photosynthetic apparatus in leaves. Mist spraying also reduced leaf temperatures and the ratio of air to leaf vapour pressure deficit (ALVPD), leading to increases in stomatal conductance (gs) and alleviation of photoinhibition at midday. It is concluded that the decline of leaf gs under high-ALVPD conditions in summer is an important factor contributing to midday depression of photosynthesis in citrus, and mist spraying is effective in alleviating midday depression of photosynthesis in citrus leaves.

The densities and viscosities of the binary mixtures of JP-10 + n-octane and JP-10 + n-decane were determined from T = 293.15 K to T = 313.15 K at atmospheric pressure, over the entire composition range. Excess volume V m E of the binary mixtures was calculated. The experimental data indicate that the addition of n-alkane has a distinct effect on the density and viscosity of JP-10, and V m E values of the binary systems are negative. Experimental data were fitted to the Redlich-Kister equation, and the adjustable parameters and the standard deviations between experimental and calculated values were estimated. Conclusions were qualitatively discussed in terms of molecular interactions. The viscosity data have been correlated with several semiempirical equations, and the Grunberg-Nissan equation gives satisfactory results.

The cracking of heptane (HEP) and the cracking of the binary system of triethylamine/heptane (TEA/HEP) in a continuous tubular reactor at 3.5 MPa are studied, to test the effect of triethylamine on the pyrolysis of heptane under a supercritical condition. It is found that triehtylamine can promote the cracking of heptane under the supercritical condition, and more effective in lower temperatures. The selectivity of ethane, ethylene, propylene, and C4 by pyrolysis of TEA/HEP is notably higher than that by HEP in a low temperature, while the difference of the selectivity is weak when in a high temperature. The kinetic character of the cracking of heptane under the supercritical condition is studied, through which the activation energy and the pre-exponential factor are obtained by pseudo-isothermal method with a quick convergence process.

Little is known about the risk factors for suicide among psychiatric inpatients in China. In this study we identified the risk factors of suicide among psychiatric inpatients at Guangzhou Psychiatric Hospital. All psychiatric inpatients who died by suicide during the 1956-2005 period were included in this study. Using a case-control design, 64 inpatients with schizophrenia who died by suicide were compared with a matched 64 controls. The results indicate that the rate of suicide was 133.1/100,000 admissions (95%CI 103.4-162.9). There were no significant differences in the method, location, or time of suicide between male and female inpatients. The number of hospitalizations was significantly larger in the suicide group than that in the control group. In logistic regression analyses, guilty thought, depressive mood, and suicidal ideation and suicide attempt 1 month before hospital admission were identified as independent predictors of suicide among inpatients with schizophrenia. The findings of risk factors for schizophrenic inpatient suicide should be taken into account when developing interventions to prevent suicide among these patients.

Tributylamine (TBA) was found to be effective in promoting the cracking of heptane. The conversion of heptane and the yield of gas product are both distinctly accelerated. The selectivity of propylene is remarkably promoted compared with that by cracking pure heptane at 550 °C, while at the higher temperature of 600 °C, the selectivity of all gas products changes very little. The cause to this effect could be that the butyl radical and its derivatives derived from TBA capture hydrogen from the heptane.

JP-10 has significant sensible heat sink capacities and may undergo endothermic chemical cracking for hypersonic aircraft applications without the problems associated with cryogenic fuels. Chemical initiators may accelerate the rate of cracking reactions and reduce the temperatures in a hypersonic aircraft heat exchanger/reactor. On the other hand, with the addition of an initiator some basic properties of JP-10 may change, such as volatility, which is directly related with ignition performance and combustion problems. Tributylamine (TBA) can be used as an effective initiator. Therefore, TBA and JP-10 blended fuel, as a potential fuel for hypersonic aircrafts, is worthwhile for further study. In the present work, the bubble-point vapor pressures and equilibrium temperatures for mixtures of JP-10 and TBA with different mass fractions were measured by comparative ebulliometry with inclined ebulliometers. Vapor pressures and equilibrium temperatures were correlated by Antoine’s equation with satisfactory pre...

The transesterification of sunflower seed oil was carried out in supercritical ethanol without using any catalyst. Ethyl esters of vegetable oils have several outstanding advantages because ethanol is derived from agricultural products and is renewable and biologically less objectionable in the environment. On the other hand, because of lower volatility, ignition delay and combustion problems could occur when ethyl esters are used. In the present work, ethanol is added to enhance the vapor pressure of biodiesel. The bubble-point pressures of mixtures of biodiesel and ethanol as a function of temperature were measured by comparative ebulliometry with inclined ebulliometers. Experimental data of vapor pressures and equilibrium temperatures were correlated by the Antoine equation. The bubble-point lines of pressure versus the composition at different temperatures and the temperature versus the composition at different pressures were obtained. It is found that the mixtures of biodiesel and ethanol have visibl...

Bubble-point vapor pressures and equilibrium temperatures for the mixtures of ethanol and JP-10 with different mass fractions were measured by the comparative ebullionmetry with inclined ebullionmeters. Correlation between vapor pressures and equilibrium temperatures by Antoine's equation was given with satisfactory precision. The bubble-point lines of pressure versus composition at different temperatures and temperature versus composition at different pressures were obtained, and the enthalpies of vaporization at different compositions were obtained.

Triethylamine was found to be effective in promoting the cracking of heptane at the temperature of 550–650 °C. The experimental yields of ethylene and propylene are more than twice as high as the calculated values on hypothesis of no interaction between triethylamine and heptane, when the mass fraction reaches 6% at the most notable temperature of 550 °C. The accelerating mechanism is studied by gas chromatography–mass spectrometry (GC–MS) and it shows that the accelerating effect is mainly attributed to the initiative release of CH 3 CH 2 from triethylamine by the scission of the C–N bond.

Bubble-point vapor pressures and equilibrium temperatures for several mixtures with different mass fractions of a kerosene based endothermic hydrocarbon fuel (EHF) and ethanol were measured by comparative ebulliometry with inclined ebulliometers. Correlation between vapor pressures and equilibrium temperatures by the Antoine equation was given with satisfactory precision. The bubble-point lines of pressure versus composition at different temperatures and temperature versus composition at different pressures were obtained. The pseudo binary systems of EHF+ethanol appear with very large positive deviations from Raoult's law. It follows that the addition of ethanol had a critical effect on the vapor pressure of fuels. Ethanol may be an effective oxygenated hydrocarbon additive to adjust the volatility of EHF.

Many metal-oxide candidates for photoelectrochemical water splitting exhibit localized small polaron carrier conduction. Especially hematite (α-Fe2O3) photoanodes often suffer from low carrier mobility, which causes the serious bulk electron-hole recombination and greatly limits their PEC performances. In this study, the charge separation efficiency of hematite was enhanced greatly by coating an ultrathin p-type LaFeO3 overlayer. Compared to the hematite photoanodes, the solar water splitting photocurrent of the Fe2O3/LaFeO3 n–p junction exhibits a 90% increase at 1.23 V versus the reversible hydrogen electrode, due to enlarging the band bending and expanding the depletion layer.

The electrochemical behavior of three electrolyte solutions containing Grignard reagents (RMgBr) with different organic groups were investigated with regard to the potential application in rechargeable magnesium battery. It is found that the electrochemical reversibility of magnesium deposition and dissolution processes and the anodic stability of the Grignard electrolyte can be significantly improved by replacing alkyl group with more stable 4-Fluorophenyl group. In addition, the ionic conductivity of the Grignard electrolyte solution is enhanced by 1.5 times by such a replacement. The test results indicate that 4-Fluorophenyl-MgBr/THF solution could be promising for use in rechargeable magnesium battery systems. Keywords: Grignard reagent, Electronic effect, Electrochemical reversibility, Anodic stability, Rechargeable magnesium battery

The data of density and viscosity for binary mixtures of N-methylpiperazine (NMP) with methylcyclohexane (MCH) or n-heptane have been measured from T = 298.15 K to T = 313.15 K at atmospheric pressure. Excess volume, VmE, for the binary mixtures are then calculated. Positive values of VmE are observed over the entire composition range, and the maximum value is 0.622 cm3·mol−1 at 313.15 K. The excess results are discussed in terms of the changes of molecular interactions in the mixtures, and the data of VmE are fitted against the composition with the Redlich−Kister type equation. The viscosities have also been correlated with several semiempirical equations. These physical property data and calculations provide valuable information on the development and application of piperazine derivatives.

Metal–semiconductor–metal-structured GaN ultraviolet photodetectors have been fabricated on sapphire substrates by metalorganic chemical vapor deposition. The properties of GaN photodetectors have been improved through thermal annealing. With a 3 V bias, the very low dark current is about 200 pA, the maximum responsivity of 0.19 A/W is achieved at 362 nm, and the corresponding detectivity is 1.2×1011 cm Hz1/2/W. The physical mechanism of the effects of thermal annealing also has been studied.

In the novel title carboxyl­ate-bridged trinuclear zinc–cerium complex, bis(2,2′-bi­pyridine)­hexakis-μ-methacryl­ato-nitrato­cerium(III)­dizinc(II), [Zn2Ce(C4H5O2)6(NO3)(C10H8N2)2], the Ce and each of two Zn atoms are bridged by three bidentate carboxyl­ate groups. The Ce⋯Zn separations are 4.011 (1) and 3.982 (1) A. The Ce atom is eight-coordinate in irregular polyhedron. Each Zn atom is five-coordinate, with a distorted pyramidal geometry.

The eminent global energy crisis and growing ecological concerns in the past two decades lead to intensive development in the fields of clean energy sources such as wind and solar power. The successful penetration of green energy technologies highly depends on the deployment of large scale energy storage systems (ESS) with low cost, safe, and longevity. Lithium ion batteries (LIB) have been well acknowledged as EES with high energy density and long cycling life, and are superior to other conventional batteries. However, their inherent safety and cost issues related to the use of expensive, toxic and flammable organic electrolyte and superfast charging performance are still challenges for their applications in large-scale EES such as electric vehicles and smart grids [1]. To meet the needs of EES, batteries based on aqueous electrolytes are attractive candidates compared to the present LIB utilizing flammable and expensive organic electrolytes because of their improved safety and low cost. For these reasons, aqueous batteries, including Pb-Acid, Ni-Cd and Ni-MH batteries, are widely used in many markets such as electric scooters and automatically guided vehicles. However, the Pb-Acid batteries and Ni-Cd batteries raise the problem of toxic heavy-metal pollution, while the market of Ni-MH batteries is limited by its high cost due to the use of rare-earth metal for anodes [2]. So it is necessary to develop a new type of aqueous battery with qualities of low cost, safety, environmental benignity, long cycle life and acceptable energy density. Zn is an ideal anode for aqueous rechargeable batteries due to its abundance in the nature and possesses a high theoretical capacity (820 mAh/g) and a low negative potential (-0.762 V vs. SHE). Various rechargeable Zn-based batteries have been investigated (Ni-Zn, Zn-air and Zn-Br flow battery etc.) [3]. Recently, a promising aqueous Zn-LiMn2O4 (LMO) rechargeable battery system has attracted attentions as a low cost, ecologically friendly and safe battery. The estimated energy density of the system is 50-80 Wh/kg, which is comparable to conventional aqueous systems such as Lead-Acid batteries [4]. However, shape change and dendritic shorting of the Zn electrode prevent the commercialization of these battery technologies [3]. Herein, we present an innovative design of aqueous battery based on Zn-LMO system, which used the concept of immobilized Zn2+ions to prevent the metal dendrite in Zn-based batteries and optimized a nontoxic, high conductivity, noncorrosive, and low-cost neutral aqueous solution as electrolyte. Therefore, this new design of Zn-LMO aqueous battery exhibits an improved rate capability and delivers good cycling performance while still maintaining an acceptable energy density. As shown in Fig.1 and Fig.2, the Zn-LMO pouch cell provides a high discharge capacity of 120 mAh/g (based on the weight of LMO) at 0.5C at room temperature with an average discharge potential of 1.88 V. The system showed a good rate capability, maintaining 99, 92.5, and 74.3% of the 0.5C value at rates of 1C, 2C, and 4C, respectively. In addition, the battery also exhibited an excellent good cycle performance even at higher temperature of 60℃（Fig.2）which were attributed to the well optimized negative, positive and electrolyte combination and composition. Given the unique advantages (performance, scalability, low cost, safety and environmental benignity) of this cell, it’s optimal for stationary storage applications of renewable energies, such as solar and wind, and energy integration into the grid. Fig. 1. Charge/Discharge profiles (25℃) of Zn-LMO battery at various current densities from 0.5C to 4C. Cut voltage is 1.5 V-2.3 V. Fig. 2. Cycle performances and coulombic efficiency (25℃ and 60℃) of Zn-LMO battery at 4C. Reference [1] J.M. Tarascon, Nature 414 (2001) 359. [2] F. Beck, Electrochimica Acta 45 (2000) 2467. [3] X.G. Zhang, Encyclopedia of Electrochemical Power Sources (2009) 454. [4] J. Yan, Journal of Power Sources 216 (2012) 222. Figure 1

The Wnt/β-catenin signaling pathway plays a critical role in directing cell fate during the embryonic development of animals and humans. To investigate the effects of the Wnt/β-catenin signaling pathway on gastrointestinal development and differentiation, we studied the expression pattern of β-catenin, a key component of the pathway, in the gastrointestinal tissues of embryonic and perinatal rats. Immunohistochemistry was used to examine the expression levels of β-catenin in Sprague Dawley (SD) rat embryos at days 13, 18 and 21 and in SD rats at 1, 3, 7 and 28 days of age. We observed that the expression of β-catenin was greater and more diffuse in the gastrointestinal tissues of rat embryos at days 18 and 21 of gestation and in SD rats at days 1 and 3. In conclusion, our data suggest that β-catenin also plays an important role in the development of gastrointestinal tissues during the middle and late embryonic periods and the early postnatal period.

Volatility and flash point for the pseudo-binary mixtures of sunflower seed-based biodiesel+ethanol were measured over the entire composition range. The biodiesel was prepared by the transesterification of sunflower seed oil in supercritical methanol without using any catalyst. The vapor pressures of mixtures of biodiesel+ethanol as a function of temperature were measured by comparative ebulliometry with an inclined ebulliometer. The vapor pressures versus composition at different temperatures and temperatures versus composition at different pressures were obtained from Antoine correlations. It is found that ethanol can adjust effectively the volatility and flash point of the biodiesel. The correlation of the flash points with the vapor pressure data for the pseudo-binary mixtures of biodiesel+ethanol displays agreement with the experimental data obtained by closed cup test.

To be able to represent the whole hierarchical phrase structure, 10 types of Chinese chunks are defined. The paper presents a method of Chinese shallow Paring based on Support Vector machines (SVMs). Conventional recognition techniques based on Machine Learning have difficulty in selecting useful features as well as finding appropriate combination of selected features. SVMs can automatically focus on useful features and robustly handle a large feature set to develop models that maximize their generalizability. On the other hand, it is well known that SVMs achieve high generalization of very high dimensional feature space. Furthermore, by introducing the Kernel principle, SVMs can carry out the training in high-dimensional space with smaller computational cost independent of their dimensionality. The experiments produced promising results.

The effect of high irradiance (HI, photosynthetically active photon flux density of 1 300 µmol m−2 s−1) on net photosynthetic rate (P N), chlorophyll fluorescence parameters, and xanthophyll cycle components were studied in fruit tree bayberry leaves. HI induced the photoinhibition and inactivation of photosystem 2 (PS2) reaction centres (RCs), which was characterized by decreased P N, maximum yield of fluorescence after dark adaptation (Fm), photochemical efficiency of PS2 (Fv/Fm) and quantum yield of PS2 (ΦPS2), and increased reduction state of QA (1-qP) and non-photochemical quenching (NPQ). Initial fluorescence (F0) showed a decrease after the first 2 h, and subsequently increased from the third hour exposure to HI. Furthermore, a greater increase in the ratio (Fi-F0)/(Fp-F0) which is an expression of the proportion of the QB non-reducing PS2 centres, whereas a remarked decrease in the slope of Fi to Fp which represents the rate of QA reduction was observed in leaves after HI exposure. Additionally, HI caused an increase in the pool size of the xanthophyll cycle pigments and sustained elevated contents of zeaxanthin (Z), antheraxanthin (A), and de-epoxidation state (DES) at the end of the irradiation period. During HI, decreased Fm, Fv/Fm, ΦPS2, NPQ, slope of Fi to Fp, V+A+Z, and DES, and increased F0, 1-qP, ratio (Fi-F0)/(Fp-F0), and V were observed in dithiothreitol (DTT)-fed leaves compared to control ones under the same conditions. Hence photoinhibition caused by HI in bayberry was probably attributed to inactivation of PS2 RCs, and photoprotection from photodamage were mainly related to the xanthophyll cycle-dependent heat dissipation in excess photons.