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The purpose of this paper is to investigate the hydrolytic stability of several S‐hydroxyethyl N,N‐dialkyl dithiocarbamate‐derived borates SNB1, SNB2, and SNB3, to evaluate their tribological performances used as additives in polyalpha olefins (PAO), and to explore the tribochemical action mechanism.

First, the three additives are synthesized and characterized. Second, the hydrolytic stabilities of the three compounds are investigated. As the third step, they are, respectively, added to PAO and a series of samples with different concentrations of the additives in PAO are prepared, respectively. Their tribological properties are evaluated with two types of four‐ball machines, and then the wear scars were observed using a JSM‐5600LV scanning electron microscope. Finally, the elements on the worn surface are analyzed with a X‐ray photoelectron spectroscope (XPS).

The three novel compounds possess relatively good hydrolytic stabilities, excellent anti‐wear (AW) performances, friction reduction properties, and load‐carrying capacity. There is an optimum concentration of each of the three additives for their AW properties. According to the XPS analytical results, a boundary lubrication protective film has formed during friction consisting of FeSO₄ film, Fe₂O₃ film, and the complicated adsorption film composed of N‐containing organic compounds. In the protective films, a large quantity of compounds containing element B is not found.

The antioxidation performances and the anticorrosion properties are not estimated.

Three novel AW/extreme pressure (EP) additives are synthesized, and may be they have the potential industrial application as AW/EP additives in lubricating oil.

The present work provides a research method of N,S‐containing organic borates as lubricating oil additives.

Fluted pumpkin seed shell, an abundant and inexpensive natural resource in Nigeria, was used as a precursor to adsorbent production for the removal of suspended and dissolved particle (SDP) from initially coagulated coal washery effluent (CWE). Key parameters such as contact time, adsorbent dose, pH and temperature were investigated using batch mode. The adsorption equilibrium, thermodynamics and kinetics of SDP on H₃PO₄ treated shell (FPA) and NH₄Cl treated shell (FPS) were examined at specified temperatures. Equilibrium data sufficiently fit the Langmuir isotherm model (R² > 0.99; SSE < 0.09). The pseudo-second order kinetic model provides the best correlation (R²>0.99;SSE<0.1) with the experimental data. The evaluated ΔG○ and ΔH○ indicate the spontaneous and endothermic nature of the process. This study demonstrates that pumpkin seed shell could be utilized as low cost, renewable, ecofriendly bioadsorbent for the removal of SDP from CWE.

The purpose of this paper is to propose a magnetic‐geared motor with permanent magnets only on the high‐speed rotor as a solution to the problems of magnetic gears. Magnetic gears have some advantages such as no mechanical loss and maintenance‐free operation that are not observed in conventional mechanical gears. Furthermore, they have inherent overload protection. A novel structure which the magnetic gear is integrated with the brushless motor (magnetic‐geared motor) was proposed by Atallah et al. This magnetic‐geared motor is based on the magnetic gear which consists of a high‐ and low‐speed rotor, and a stator. Although this magnetic‐geared motor has a high‐torque density, problems with manufacturing and cost exist because multi‐pole permanent magnets are mounted on the high‐speed rotor and stator.

A magnetic‐geared motor with permanent magnets only on the high‐speed rotor was proposed and its operational principle was described. The cogging torque characteristics were mathematically formulated and the authors ascertained that the cogging torque contains components of multiples of 60th order. In order to verify the order of the cogging torque, the 3‐D finite element method analysis was conducted and measurements on a prototype were carried out.

The 60th component and its multiples were observed in the computed and measured cogging torque waveform. However, the cogging torque characteristics, especially the order of the cogging torque on the low‐speed rotor, have not been clarified.

In the near future, cogging torque reduction methods will be proposed, and verified by conducting 3‐D FEM analyses and carrying out measurements on a prototype. Furthermore, the torque characteristics when an electrical current is applied to the coils and the eddy‐current loss characteristics will be verified.

The purpose of this paper is to examine whether China is still a passive price taker from the US soybean futures, or instead domestic futures market has developed certain degrees of pricing power through time. The finding helps to identify the importance of China soybean futures in the perspective of portfolio selection for international futures traders. If China soybean futures market is no longer a price taker after the subprime crisis, traders need to include it as a separate category in their portfolio.

This paper uses exponential generalized autoregressive conditional heteroskedasticity-generalized error distribution (EGARCH-GED) and generalized autoregressive conditional heteroskedasticity-generalized error distribution (GARCH-GED) models to test spillover effects between Dalian Commodity Exchange (DCE) and Chicago Board of Trade (CBOT) soybean futures. The authors divide daily samples into three subperiods based on the subprime crisis. Three research questions – whether China is still the price taker, the importance of Chinese soybean futures in international futures portfolio selection, and the influences of subprime crisis on soybean futures volatility relationship – are examined by comparing estimation results through time and different contracts.

The spillover effect from CBOT soybean futures to DCE No. 1 soybean futures becomes weaker through time. China is no longer a soybean futures price taker after the subprime crisis. The authors also find the shocks of bearish news on DCE soybeans are greater than those of bullish news. Potential volatility of DCE in long positions is bigger than that in short positions.

China is the largest soybean importer. DCE is a very important futures market for non-genetically modified soybeans. It is necessary for both international and domestic futures traders to understand the changes in international soybean futures price relationship and take corresponding strategies. It is also important for market to realize that DCE soybean futures are to a less degree price taker after the subprime crisis.

The paper applies EGARCH-GED and GARCH-GED models to identify changes in spillover effects before, during, and after the subprime crisis. Different from other studies, this paper finds after the subprime crisis, China is no longer the soybean futures price taker. This paper also compares the spillover effects of non-genetically modified soybean futures (No. 1 soybean futures) with genetically modified soybean futures (No. 2 soybean futures).

The purpose of this paper is to study the influences of recess configurations on the performances of high-speed hybrid journal bearing. Hybrid journal bearing earns increasing attention in high-speed machine tool spindle owing to its intrinsic outstanding performances of low temperature rise and high stability.

To investigate the coupled effects of temperature, turbulence and the interaction between lubricant and journal/bearing bush, a thermal fluid-structure interaction approach is presented and validated by the experimental results.

Ladder-type recess has excellent tribological characteristics in decreasing temperature rise, improving stability and inhibiting cavitation, which are all beneficial to improve the performances of high-speed spindle system.

This work can be a valuable guide for the future high-speed hybrid journal bearing design.

This paper aims to propose criteria and indicators for the adoption of e-books in libraries in the context of the cloud computing paradigm.

This paper carried out bibliographical and documentary research and the application of a questionnaire. Sampling focused on five library managers and five e-book vendor managers.

A proposal is presented containing a set of three criteria and their respective indicators. The technology platform criterion consists of seven indicators: patron data privacy, patron data security, availability of services, accessibility of information in e-books, interoperability of the technology platform, digital preservation and portability of e-books. The criterion for the acquisition of e-books involves three indicators: forms of commercialization, acquisition models and selection of e-book titles. The criterion for the circulation of e-books is divided into two indicators: unlimited and limited use. In the unlimited use mode, there are no limits on the use of e-books. In limited use, there are 11 levels of permissions: available copies, number of loans under each license, duration of the license, interlibrary loan, reading only in digital format, reading online via streaming only, download on the patron’s device, content printing, loan according to the patron’s identity, reservation services and renewal services.

This paper provides a set of criteria and indicators that can aid in the construction of policies and the development of collections, programs and projects directed toward the use of e-books in libraries.

This paper contributes socially by presenting a proposal that can support policies of evaluation and development of collections, projects, programs and actions around the adoption of e-books in different types of libraries.

The purpose of this paper is to develop a propeller performance measurement method for high-altitude platforms by analyzing of the propeller aerodynamic characteristics and application of a mobile testing system.

An experimental approach is adopted for this study. Considering the aerodynamic characteristics of the high-altitude propeller, the similitude of the scaled propeller model in the experiment is analyzed and determined. Then, the experimental method and procedure to obtain the propeller’s performance under different altitudes are presented, and the structure of hardware and software and the key techniques of the testing system are introduced in detail.

The applicability and effectiveness of the testing system is verified through comparison between experimental and numerical results. In addition, the performance of the 6.8-m propeller for a high-altitude airship is tested, which proves that the high-altitude propeller can meet the requirements of the propulsion system.

The testing methodology and the mobile testing system could be applied to aerodynamic performance evaluation of the high-altitude propellers under different altitudes.

This testing approach exhibits significant time and cost benefits over many other experimental methods to obtain the performance of the high-altitude propellers, which is important in the preliminary design of the propulsion system for high-altitude platforms.

The purpose of this paper is to measure Farmer’s adoption tendency towards drought shock, risk-taking networks and modern irrigation technology.

Based on this assumption, this paper evaluated the data gathered from 498 household surveys of Zhangye, Gansu province, PRC, by using the binary probit model. First, the empirical data was analyzed for evaluating the impact of drought shock and risk-taking tendencies on the adoption of modern irrigation technology by farmers. Second, the authors introduced informal risk-bearing networks with formal risks. Final, based on the empirical results, the sustainability test, along with the marginal effect analysis and the degree of impact was carried out.

The results show that the drought shock has a significantly deferent effect on the modern irrigation technology of the farmers. The probability of using technology for each level of drought loss is reduced by 15.02%. The risk-taking network has a significant role in promoting the modern irrigation technology of farmers. The probability of adoption for each additional unit of rural household labor security supply, the likelihood of adoption by farmers increased 23.11%, the probability of approval for each level of relative support, and neighborhood assistance by farmers increased by 13.11% and 17.88% respectively. This study further revealed that insurance purchases enabled farmers to adopt new irrigation technology with the probability increased by 24.99%; easily available bank loans increased the probability of farmers using irrigation technology by 31.89%. From the perspective of interactions between farmers, the risk-taking network can alleviate the inhibitory effect of drought impact towards the adoption of irrigation technology. Among the control variables, the number of years of education, the age of farming, the degree of arable land, the distance from home to the market, and the price of water all has significant effects on the adoption of modern irrigation technology by farmers.

The novelty of the study is that it illustrated the interactive influence of drought shock and risk-taking networks on the farmer’s adoption tendencies of modern irrigation technologies, the inner relationship among drought impact, the risk-taking network and the farmer’s adoption behavior and provide an interactive relationship between the formal risk-taking network and the non-risk-taking network in farmer’s technology adoption.

This article examines the impact of different policy instruments on livestock farmers' willingness to recycle manure. The results shed light on the optimal policy combination.

A game theoretical framework is constructed to illustrate farmers' optimal strategies under different policies. Theoretical results are empirically tested by survey data from beef cattle farmers in Central China.

Empirical results show that penalties work better than subsidies if each type of policy is implemented separately. The authors also find a positive interaction between subsidy and penalty policies, suggesting that a combination of subsidy and penalty policies produces the best outcome in incentivizing livestock farmers to recycle manure. Furthermore, planting and breeding simultaneously have the strongest effect on increasing livestock farmers' willingness to recycle manure, suggesting that the combination of planting and breeding can be an optimal strategy for manure management.

This study is based on firsthand survey data and provides new evidence on the effectiveness of alternative environmental policies on manure recycling.