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This study aims to get the essential data of the solubility and diffusion coefficient of gas in jet fuel for appropriately designing a kind of on-board inert gas generation system.

A test apparatus based on pressure–decay method was constructed to measure solubility and diffusion coefficient of gas in liquid. The test apparatus and method were verified via measurement of solubility and diffusion of CO₂ in the pure water.

The solubility of CO₂ and O₂ in RP-3 jet fuel with the temperature from 253 to 313 K under three various pressures were measured and compared with theoretical value calculated by a relative density method provided in the standard of ASTM D2780-92, and the deviation is within 10 per cent. The diffusion coefficients of CO₂ and O₂ in RP-3 jet fuel are determined by monitoring the gas pressure in a hermetic cell versus time with the temperature from 253 to 333 K. The measured diffusivity-temperature relation can be well fitted through the Arrhenius equation for engineering applications. The obtained correlation can be used to predict the diffusion coefficient of CO₂ and O₂ in RP-3 jet fuel under a wide temperature range.

The semi-empirical correlation of solubility and diffusion coefficient in RP-3 jet fuel obtained from the experimental data could be used to support the design of an inert gas generation system.

There are no essential data of solubility and diffusion of CO₂ and O₂ in RP-3 jet fuel; therefore, it is fatal if the quantity and rate of mass transfer of CO₂ and O₂ in RP-3 jet fuel must be assessed, e.g. during the design of green on-board inert gas generation system.

This study aims to seek a new economic and environmental protection fuel tank inerting method.

The principle that serves as the basis for the cooling inerting process is described, the workflow of the cooling inerting system is designed, the mathematical model of the cooling inerting system is established, and the important performance changes of cooling inerting in the flight package line and the influence of key parameters on it are simulated by using Modelica software.

The results show that the cooling inerting system can be turned on to quickly reduce the vapour concentration in the gas phase in the fuel space and reduce the temperature below the flammability limit. Within a certain range of pumping flow, the inerting effect is more obvious when the pumping flow is larger. Simply running the cooling inerting system on the ground can remain the tank in an inert state throughout the flight envelope.

However, cooling inerting is suitable for models with fewer internal heat sources. An excessive number of internal heat sources will lead to inerting failure.

This study provides theoretical support for the feasibility of cooling inerting. Cooling inerting does not require engine air, and the cooling is mainly accomplished with air, which places a small load on the cooling system and has a much lower cost than the airborne hollow fibre film inerting technology widely used at present. It is a promising new inerting technology.

The purpose of this paper is to analyze the effects of the PRD geometric parameters, including the area and aspect ratio, on the discharge and force characteristics of pressure relief process under various plenum compartment pressures and Mach numbers.

Under various plenum compartment pressures and Mach numbers, the effect of the area and aspect ratio on the discharge and force characteristics of the PRD are numerically investigated via a three-dimensional steady Reynolds-averaged Navier–Stokes equations solver based on structured grid technology.

When the aspect ratio remains constant, the discharge coefficient C_D, thrust coefficient C_T and moment coefficient C_M are not affected by the PRD. When the area is constant, the aspect ratio dramatically impacts the discharge and force characteristics because the aspect ratio increases, the discharge coefficient C_D of the PRD decreases, and the thrust coefficient C_T and the moment coefficient C_M both increase. When the aspect ratio is 2, the discharge coefficient C_D decreases by 14.7 per cent, the thrust coefficient C_T increases by 10-15 per cent, and the moment coefficient C_M increases by 10-23 per cent compared with when the aspect ratio is 1.

This study provides detailed data and conclusions for nacelle PRD researchers and actual engineering applications.

On the basis of considering the influence of operating conditions on the discharge and force characteristics of the nacelle PRD, the impact of geometric parameters, including the area and aspect ratio on the discharge and force characteristics is comprehensively considered.

This paper aims to improve the previous fuel scrubbing model and find out the relationship between bubble diameter and scrubbing efficiency (ƞ).

A fuel tank scrubbing test bench was established to verify the accuracy of this model. Ullage and dissolved oxygen concentration were measured, and images of bubble size and distribution were collected and analyzed using image analysis software.

The bubble diameter has a great influence on ullage and dissolved oxygen concentration during the fuel scrubbing process. The scrubbing efficiency (ƞ) has an exponential relationship with bubble diameter and decreases rapidly as the bubble diameter increases.

The variation of the ullage and dissolved oxygen concentration predicted by this model is more accurate than that of the previous model. In addition, the study of bubble size can provide a guidance for the design of fuel scrubber.

This study not only improves the previous fuel scrubbing model but also develops a method to calculate scrubbing efficiency (ƞ) based on bubble diameter. In addition, a series of tests and analyses were conducted, including numerical calculation, experiment and image analysis.

The purpose of this study is to measure the mass diffusion coefficient of nitrogen in jet fuel using digital holography interferometry for cost-effective designing and modeling of the aircraft tank inerting system.

The mass diffusion coefficients of N₂ in RP-3 and RP-5 jet fuels were measured by digital holography interferometry at temperatures ranging from 278.15 to 343.15 K. The Arrhenius equation is used to adequately describe the relationship between mass diffusion coefficients and temperature. The viscosities of RP-3 and RP-5 jet fuels were also measured to examine the accuracy of the Stokes–Einstein model in calculating mass diffusion coefficients.

As temperature increases from 278.15 to 343.15 K, the mass diffusion coefficients increase 4.23-fold for N₂ in RP-3 jet fuel and 5.13-fold for N₂ in RP-5 jet fuel. The value of Dµ/T is not constant as the Stokes–Einstein equation expressed, but is a weak linear function of temperature.

A more accurate diffusion model is proposed by fitting the measured Dµ/T with the temperature and calculating the mass diffusion coefficients of N₂ in RP-3 and RP-5 jet fuels within 10 per cent relative deviation.

A measurement system for mass diffusion coefficients of N₂ in RP-3 and RP-5 jet fuels was constructed based on the digital holography interferometry. The mass diffusion coefficient can be expressed by a uniform polynomial function of temperature and viscosity.

The purpose of this paper is to explore the longitudinal influence of gender, age, education level, organizational tenure and emotional intelligence on three dimensions of knowledge hiding over time.

A longitudinal study using two-wave data sets of 390 employees in Chinese enterprises was conducted to build fixed, continuous and interacting models for investigating the effects of individual differences on the processes of knowledge hiding over time.

This research uncovered the changing relationships of individual differences on knowledge-hiding behaviors over time, such that age correlates with rationalized hiding in the interacting model, indicating younger employees are less likely to choose rationalized hiding when facing situation changes; and education level, organizational tenure and emotional intelligence moderate knowledge hiding over time, implying individuals with better education, longer tenure and higher emotional intelligence tend to exhibit more rationalized hiding behaviors rather than evasive hiding and playing dumb behaviors at Time 2.

One of the novel contributions of this study is that it tests the longitudinal effect of individual differences on knowledge hiding, providing a vertical perspective, and thereby contributing to the body of knowledge in knowledge management. The study also constructs fixed, continuous and interacting models to measure the covering longitudinal influences, thus making the research original.

Gear transmissions are widely utilized in practice. This paper aims to uncouple the crack feature from the cracked time-varying mesh stiffness (TVMS) and investigate the effects of the crack on the nonlinear dynamics of a spur gear pair.

An approximate method to simulate the cracked TVMS is proposed by using an amplitude modulation function. The ratio of mesh stiffness loss is introduced to estimate the TVMS with different crack depths and angles. The dynamic responses are obtained by solving a torsional model which takes the non-loaded static transmission error, the backlash and the cracked TVMS into account. By using the bifurcation diagram, the largest Lyapunov exponent (LLE) and dynamic mesh force, the influences of crack on nonlinear behaviors are examined. The dynamic characteristics are identified from the phase diagram, Poincaré map, dynamic mesh force, time series and FFT spectra.

The comparison between the healthy and cracked gear pairs indicates that the crack affects the system motions, such as the obvious changes of impact force and unpredictable instability. Besides, the additive and difference combination frequencies can be found in periodic-1 and -2 motions, but they are covered in periodic-3 and chaotic motions. Deeper crack is an important determinant of the nonlinear behaviors at a higher speed.

The research provides an interesting perspective on cracked TVMS and reveals the connection between crack and nonlinear behaviors of the gear pairs.

This study aims to develop a facile ligand-exchange strategy to promote nano-sintering of oleylamine (OAM)-capped silver nanoparticles (AgNPs). By using ligand exchange process with NH₄OH to remove OAM from the surface of AgNP, this study reports effectively reducing the sintering temperature of AgNPs to achieve low-temperature nano-sintering. Compared with untreated AgNPs of OAM-capped, NH₄OH-treated AgNPs possess superior sintering performance that could be applied to a fractional generator device as conductor and in favour of the fabrication of flexible circuit modules.

First, oleylamine is used as reductant to synthesize monodisperse AgNPs by a simple one-step method. Then ligand exchange is used with NH₄OH at different treating times to remove OAM, and micro-Fourier transform infrared spectroscopy and contact angle test are applied to clear the mechanism and structure characteristics of these processes. Finally, NH₄OH-treated AgNPs sediment sintering is used at different temperatures to test electrical resistivity and use ex situ scanning electron microscopy combined with in situ X-ray diffraction to study changes in microstructure in the whole nano-sintering process.

The AgNPs are always capped by organic ligands to prevent nanoparticles agglomeration. And oleylamine used as reductant could synthesize desirable size distributions of 8–32 nm with monodisperse globular shapes, but the low-temperature nano-sintering seemed not to be achieved by the oleylamine-capped AgNPs because OAM is an organic with long C-chain. The ligand exchange approach was enabled to replace the original organic ligands capped on AgNPs with organic ligands of low thermal stability which could promote nano-sintering. After ligand exchange treated AgNPs could be sintered on photo paper, polydimethylsiloxane (PDMS) and polyethylene terephthalate flexible substrates at low temperature.

In this research, the method ligand exchange is used to change the ligand of AgNPs. During ligand exchange, NH₄OH was used to treat AgNPs. Through the treatment of NH₄OH, the change of hydrophilic and hydrophobic properties of AgNPs was successfully realized. The sintering temperature of AgNPs can also be reduced and the properties can be improved. Finally, the applicability of the AgNPs sediment with this nano-sintering process at low temperature for obtaining conductive patterns was evaluated using PDMS as substrates.

This paper answers, in the Chinese stock market, who can realize the “spot value” of corporate social responsibility (CSR).

The authors use event-study to build the research framework. Using CSR report content analysis, the authors measure the specification level of CSR disclosure. Applying the Baidu index, the authors mine Chinese investors’ profiles data to investigate retail investor heterogeneity closely.

The authors find strong evidence that the measure captures a behavioral bias in CSR pricing: firms that choose to disclose CSR report experience positive abnormal return more among retail investors than institutional investors, more among young investors than older, but no difference between female and male investors.

For Chinese public firms, the authors give them evidence that they can realize positive abnormal returns by applying certain CSR disclosure strategies. For Chinese investors, especially retail investors and youths, the authors ask them to rethink whether their positive evaluation of CSR is a rational trade-off choice or whether they are fooled by the “hedging mask” and “attention-grabbing.”

The findings can give some suggestions to regulators: encouraging voluntary disclosure and reducing mandatory disclosure can drive enterprises to engage in more CSR activities because the voluntarily CSR disclosure can realize both long-term value and “spot value.” Complementarily, a more rigorous CSR report auditing regulation can suppress the “greenwash” by increasing the “lying cost.”

Using behavioral finance theory, the authors connect the gap between neoclassical research on the “U-shaped” value realization of CSR and the increasing voluntary CSR disclosure in the Chinese market. The authors find that heuristic reason and emotionality orientation results in the Chinese “CSR-friendly” market.

This study aims to reveal how mobile app stickiness is formed and how the stickiness formation process differs for apps of different social levels.

This study proposed and validated a stickiness formation model following the cognitive–affective–conative framework. Data were collected from surveys of 1,240 mobile app users and analyzed using structural equation modeling. Multigroup analysis was applied to contrast the stickiness formation process among apps of different social levels.

This study revealed a causal link between cognitive, affective and conative factors. It found partial mediation effects of trust in the association between perceptions and satisfaction, and the full mediation role of satisfaction and personal investment (PI) in the effects of subjective norm (SN) on stickiness. The multigroup analysis results suggested that social media affordances benefit stickiness through increased PI and strengthened effects of SN on PI. However, it damages stickiness through increased perceived privacy risk (PPR), decreased trust and strengthened effects of PPR on trust.

This study contributes to both stickiness scholars and practitioners, as it builds a model to understand the stickiness formation process and reveals the effects of the “go social” strategy. The novelty of this study is that it examined social influences, considered privacy issues and revealed two mediation mechanisms. The findings can guide the improvement of mobile app stickiness and the application of the “go social” strategy.