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Focusing on 48 Chinese films made by the representatives of the fifth- and sixth-generation directors (i.e. Zhang Yimou, Chen Kaige, Jia Zhangke and Feng Xiaogang), this paper reveals: (1) These directors’ preferences for the themes with locality are related to the popularity of Chinese local literature except for their nostalgia for hometowns; (2) The overseas distribution of these films cannot be separated from the support of the state policies, while 1985, 1995, 1999, 2002 and 2018 are found to be five milestone years in the development of the Chinese film industry to promote international co-production and distribution; (3) Subtitling is the most popular mode translation used to distribute Chinese films in English speaking countries, and the subtitling of these films always involves English native speakers’ contribution to various degrees.

Surface reaction kinetics and light absorption properties of a photocatalyst are essential demands for efficiently solar to chemical energy converting. In this study, plasmonic WO3–x was firstly applied to photocatalytic alkylation of arenes under red light irradiation. The oxygen vacancies, both on the surface and in the bulk of WO3–x, allow abundant free electrons to increase carrier densities and support its LSPR using low energy photons. The surface oxygen vacancies have more functions: they not only release surface tungsten sites which ensure the chemisorption of alcohols due to the coordianation ability but also promote the activation of alcohols via an efficient transport of the holes on the neighbouring O sites to chemisorption alcohol species. In brief, the bulk oxygen vacancies provide abundant charges and the surface vacancies promote the bond adsorption and activation abilities, which ensure the high efficiency of photocatalytic alkylation of C–H.

WO3–x (W-1) was used to achieve controllable photoisomerization of linear olefins without substituents under 625 nm light irradiation. Thermodynamic and kinetic isomers were obtained by regulating the carbon chain length of the olefins. Terminal olefins were converted into isomerized products, and the internal olefin mixtures present in petroleum derivatives were transformed into valuable pure olefin products. Oxygen vacancies (OVs) in W-1 altered the electronic structure of W-1 to improve its light-harvesting ability, which accounted for the high activity of olefin isomerization under light irradiation up to 625 nm. Additionally, OVs on the W-1 surface generated unsaturated W5+ sites that coordinated with olefins for the efficient adsorption and activation of olefins. Mechanistic studies reveal that the in situ formation of surface π-complexes and π-allylic W intermediates originating from the coordination of coordinated unsaturated W5+ sites and olefins ensure high photocatalytic activity and selectivity of W-1 for the photocatalytic isomerization of olefins via a radical mechanism.

In this study, we prepared Au nanospheres (NSs)@Ag nanorods (NRs) for colorimetric monitoring of hypochlorite (ClO–). The sensing strategy is based on the redox reaction between Ag and ClO–, which ...

In this paper, we focus on the task of automatic argument quality assessment. Prior empirical methods largely ignore the syntax structure in one argument or depend on handcrafted features that have shallow representation ability. In contrast, we proposed a method that directly models syntax and topic coherence. Our method can acquire both topic coherence and syntactic information from an argument that explicitly utilizes various types of relationships among words, thus can help with argument quality assessment. Experimental results suggest that our method significantly outperforms the previous state-of-the-art method and strongly indicates syntax and coherence correlate with argument quality.

Austempered ductile iron (ADI) is produced by an isothermal heat treatment. Tempering is an effective method to increase the toughness and decrease the hardness of ADI. In the present research, the transformation of ADI was investigated after applying various tempering temperatures. The hardness of ADI samples with and without tempering was measured and the microstructure of ADI samples was analyzed by using metallographic optical microscopy. It was found that the ausferrite decomposed into dispersive cementite particles above a tempering temperature of 538 °C. Thus, the tempering process for ADI must be carefully selected so that the excellent properties of ADI are not degraded. Keywords: ADI, Tempering process, Hardness measurement, Phase transformation, Microstructure

The rolling contact fatigue resistance of austempered ductile iron (ADI) produced at various holding times was evaluated by using a twin-disk rolling configuration rig. The resulting fatigue life of ADI samples was compared with that of conventional quenched and tempered (Q&T) ductile iron samples with the same chemical composition. It was found that the macro hardness of ADI samples decreased and the fatigue life became shorter for longer holding time. For similar macro hardness, ADI samples had higher fatigue resistance as compared with Q&T ductile iron samples. Optical microscopy and scanning electron microscopy indicated that the graphite nodules acted as crack nucleation sites for the ductile iron. The cracks propagated towards either the surface or adjacent graphite nodules until the formation of pits or spalls occurred. The excellent fatigue resistance of ADI samples could be attributed to the increase of surface hardness which was caused by the strain induced transformation of retained austenite into martensite. By using X-ray diffraction, the difference of retained austenite present in the wear track and off the wear track ranged from 4.42% to 26.15%.

Controlling the amount of retained austenite is a concern in austempered ductile iron formation. Retained austenite has a strong influence on austempered ductile iron properties, such as hardness and wear resistance. In this research, the characteristics of the transformation of retained austenite were investigated as a function of the number of tempering cycles. The hardness of the austempered ductile iron samples was measured, and the specific amount of retained austenite was analyzed by x-ray diffraction (XRD). Wear tests were conducted on a ball-on-flat sliding fixture. The tempering process was found to have no effect on the hardness of the austempered ductile iron samples. This may be due to retained austenite being partially converted into brittle quenched martensite during the tempering process. However, tougher tempered martensite was also formed from existing martensite. The two effects seemed to offset each other, and no significant differences occurred in overall hardness. XRD analysis showed that under the same austempering temperature and holding time, the amount of retained austenite decreased with additional tempering cycles. Also, with the same holding time and tempering cycles, less retained austenite was contained in the matrix at higher austempering temperatures. This was due to more high carbon content austenite and needle-like ferrite being present in the austempered ductile iron matrix. In addition, tempered austempered ductile iron exhibited significantly higher wear resistance as compared to traditionally treated ductile iron.

4140 steel and 4150 steel are different only in their carbon content. A comparison between the kinetics and microstructure of the bainite transformation of both steels has been carried out under a wide range of isothermal temperatures, in which four bainite phase matrices were generated. The four phases are upper bainite, mixed upper and lower bainite, lower bainite and mixed martensite and lower bainite (lower bainite transformed under Ms temperature). The bainite transformation kinetics-morphology characteristics of the four phases were studied and compared. Kinetics behavior patterns are shown with the developed TTT diagrams and kinetics plots- (bainite volume fraction vs isothermal holding time). The upper bainite and lower bainite transition temperatures are different and the bainite reaction time span is shorter when carbon content is higher. The n values in the Johnson-Mehl- Kolmogorov-Avrami (JMKA) equation have a wider deviation when carbon content is higher, indicating more bainite reaction variation. The activation energy required for the bainite phase transformations were compared and it was found that higher activation energy is needed when carbon content is higher. The subtle microstructure morphology differences are illustrated. This work will aid future development of 4140/4150 steels with bainitic microstructures having improved mechanical properties.

In light of the advanced international conception for e-learning translation instruction and the development of professional translation education in China, it is proposed that an e-learning platform conceived with knowledge systems be constructed. The new platform aims at utilizing advantages and characteristics of the online instruction, and at the same time categorizing instructive resources leading to knowledge service systems. This advantageous e-learning environment is featured with a collection of electronic resources of translation technology, instructive resources and interactive communication forums.

Bainite transformation is a kinetic process that involves complex solid diffusion and phase structure evolution. This research systematically studies the bainite transformation of austempered 4140 steel in a wide range of isothermal temperatures, in which four bainite phases structures were generated: upper bainite, mixed upper bainite and lower bainite, lower bainite and mixed lower bainite and martensite. The kinetics of bainite transformation has been described with a linear trend using an Avrami n-value. It was found that the bainitic ferrite sheaves grow with widthwise preference. The sheaves are stable when half-grown and are variable in length, due to austenite size limit or soft/hard impingement, or autocatalytic nucleation, or these conditions combined. The full-grown upper/lower bainite sheaves were found to be 1.9 &mu, m/1.2 &mu, m in width under the conditions of this study. Each individual bainite sheave is lath-like instead of wedge-like. The upper bainite sheaves mostly appear as broad-short-coarse lath, while the lower bainite sheaves appear as narrow-long-fine lath. The overall bainite transformation activation energy ranges from 50&ndash, 167 kJ/mol.

Scuffing can occur in various engineering components, including engine cylinders and liners, camshafts, crankshafts, and gears. Austempered ductile iron (ADI) is finding increasing application in these components due to its self-lubricating characteristics and excellent mechanical properties. The objective of this research is to study the scuffing behavior of an austempered ductile iron material austempered at different temperatures and for varying periods of time. Rotational ball-on-disk tests were run with white mineral oil as the lubricant at two sliding speeds. A step load was applied until scuffing occurred. The scuffed specimens were studied using optical and scanning electron microscopy to determine their scuffing mechanisms. Improved scuffing resistance, as evidenced by a higher scuffing load, is related to a decreased hardness and higher level of retained austenite which produce a more ductile material.

Carbonitriding is a widely accepted method of heat treatment used by North American manufacturers for plain carbon steel. While the process imparts a hard, wear resistant case, it is also associated with both size and shape distortion, which can be problematic for components in tight fitting assemblies. This research compares the effects of the carbonitriding and nitrocarburising processes on SAE 1010 steel with respect to residual stress and distortion. Results indicate that the two processes develop residual compressive stresses and are associated with both size and shape distortion. Although the magnitude of the compressive stresses in nitrocarburised steels is lower, this process was noted to give rise to overall smaller dimensional changes than the carbonitriding process. The findings from this study are applied to a manufacturing application involving the surface treatment of a thin shelled automotive component in a light loading application.

This research investigates the process of the formation of bainite in austempered 5160 steel. Steel bar samples were austenitized at 1128 K for 20 minutes followed by holding at various times from 10 seconds to 2 hours and isothermal temperatures from 561K to 728K to obtain a multi-phase matrix. Micro-hardness analysis and metallurgical optical microscopy were used to analyze the experimental results. Hardness results indicated that at the 561K, 589K, and 566K isothermal temperatures for 5160 steel, lower bainite transformation occurred. However, from 644K to 728K, upper bainite transformation was found from the steel. The formation of the bainitic phase in SAE 5160 steel was characterized using thermodynamic and kinetic theories.

A unified probabilistic framework (UPF) of partitional clustering algorithms is proposed based on Penalized Maximum Likelihood. Besides Gaussian Mixture model methods, many popular clustering methods, such as Fuzzy c-Means Algorithm (FCM), Attribute Means Clustering (AMC), General c-Means Clustering (GCM), and Deterministic Annealing (DA) Clustering can be explained as special cases within UPF. Furthermore, this UPF framework provides a general approach to design comparatively stable and effectively regularized clustering algorithms.

As global competition is getting more and more intense, there is an increasing trend manifesting the increasing interest in sustainable supply chain management. This study introduces four sustainable supply chain indicators from the upstream (supplier), middle stream (focal firm) and downstream (customer) of a supply chain to empirically examine the relationship between sustainable supply chain performance and firm performance (ROA), as well as the relationship between environmental efficiency and other three indicators. It focuses on the Energy and Utilities industries. In this study we use global firm dataset from Bloomberg professional service, and the number of observation is 86 during 2005 to 2013. We find an inversely U-shaped curve relationship between environmental efficiency in supply chain and firm' s profitability (ROA); and a U-shaped relationship between investments in operational sustainability and firm' s profitability. Also a negative relationship is found between having a new product and ROA. We provide implications obtained from our analysis of regression results for managers. We contribute to the literature by responding to the call for more empirical research in this filed, providing the evidence that sustainable supply chain performance can bring actual benefits for the firm, as long as firms identify their own position accurately and take the right action.

This research is focused on using nitriding to enhance the wear resistance of austempered ductile iron (ADI), ductile iron (DI), and gray iron (GI). Three gas nitriding processes, namely “Gas nitriding + nitrogen cooled down to 800 o F” (Blue), “Gas nitriding + cooled down to 300 o F” (Gray), and “Gas nitriding + oil quenched” (Oil) were used. This study was carried out through optical metallography, roughness measurements, microhardness, and SEM. The ball-ondisc wear tests were conducted under lubricated conditions. It was found that COF for all materials in all nitrided conditions was small (

Induction hardening is a key manufacturing process in the production of ductile iron automotive camshafts. Its desirable features include low-cost, a wearresistant surface, and ease of manufacturing. Due to the asymmetrical geometry of the camshaft, induction hardening generates non-uniform heating/cooling which leads to a variability in both the microstructure of the surface hardened case, principally the amount of retained austenite (RA), and the level of residual stress (RS). Both RA and RS can affect the contact fatigue performance of the camshaft. In the present study, automotive camshafts containing six lobes per camshaft were induction hardened to different schedules and the RA and RS (surface) variations were determined both between different lobes on the same camshaft and between camshafts that were induction hardened to different schedules. RA and RS measurements were made using x-ray diffraction methods by two independent, certified testing laboratories. Because of their low cost and ease of testing, we have also used optical metallographic methods to determine RA. A correlation was obtained between the RA values obtained by x-ray diffraction with those obtained by optical metallography. This data for ductile iron expands the database that was available for steels to higher carboncontent ferrous alloys. Finally, a correlation is made between RA content and RS level in order to define a robust process window.

To attenuate white noise, nonstationary noise and impulse noise are important for signal processing. In this letter, we present nonlinear fusion filters (NFF) based on prediction and smoothing. By means of least square fitting of a polynomial, we define and give the operators of left prediction and right prediction, left smoothing and right smoothing, central smoothing and cross-validation smoothing. In simulated experiments, it is shown that the present method is an effective one.

Ferritic nitrocarburizing is being proposed as an alternative to gas carbonitriding to improve the surface characteristics of SAE 1010 plain carbon steel automotive components without producing unacceptable part distortion. Navy C-rings are specially designed specimens for the evaluation of the distortion (size and shape) that result from any heat treatment process. In this study, gas ferritic nitrocarburizing and nitrogen cooling was used to heat treat Navy C-ring specimens of varying thicknesses (2.8 mm–19.05 mm) at temperatures ranging from 510°C to 595°C. For each combination of part thickness and heat treatment temperature, the following parameters were evaluated: size and shape distortion; XRD and OM (optical microscopy) to characterize the nature of the nitride layers formed at the surface; X-ray determination of the residual stresses in the nitride surface layers. The various combinations of nitrocarburizing temperature and time resulted in an expansion of the OD (Outside Diameter) dimension and a small deterioration in flatness. The ID (Inside Diameter) changed from a small expansion (+0.02%) for the thickest specimens (19.05 mm) to a small contraction (-0.02%) for the thinnest specimens (2.8 mm). The gap tends to close up as the thickness decreases from the thickest to the thinnest specimens. Microstructural differences were found in the nitrided layers formed at the different heat treatment temperatures. The residual stresses in the outer e-nitride layers (Fe3N) were typically tensile. On the basis of these results, preliminary recommendations are made as to heat treatment parameters to lower distortion.

The two-body abrasive wear resistance of a boronized medium carbon steel was tested on a pin-on-disk testing machine against 200 mesh (75 μm) SiC paper, with the internal stress and the degree of preferred orientation determined by X-ray diffraction analysis after every successive layer of the specimen was removed by wear. The results show that under low stress abrasive wear, both the residual compressive stress — σ xx and preferred orientation of [002] of the Fe 2 B grains can improve the wear resistance of the boronized layer. The mechanism for such influences is proposed, and an explanation of the current diversity in the influence of residual stress on wear rate is discussed.

In previous papers [L. Wang, X. Wang, J. Feng, Subspace distance analysis with application to adaptive Bayesian algorithm for face recognition, Pattern Recognition 39(3) (2006) 456-464, L. Wang, X. Wang, J. Feng, Intrapersonal subspace analysis with application to adaptive Bayesian algorithm for face recognition, Pattern Recognition 38(4) (2005) 617-621], we proposed a subspace distance. However, whether the subspace distance satisfies the triangle inequality was left open. In this note, we give positive answer to the open problem and prove our assertion.

Gaseous ferritic nitrocarburizing was investigated as a replacement for the carbonitriding process currently used to improve the surface properties of thin-shelled, plain carbon steel automotive powertrain components. Nitrocarburizing can impart a hard, wear-resistant case suitable for light load applications at lower processing temperatures than carbonitriding, thereby potentially reducing size and shape distortions and the associated need for finish grinding. Carbonitriding and gaseous ferritic nitrocarburizing were compared with respect to size and shape distortion, retained austenite, and residual stress values. Testing was performed on a torque converter piston, an automotive powertrain component stamped from a sheet of 3-mm cold-worked SAE 1010 steel. A total of 53 pistons were used. While the heat treatment conditions for the carbonitrided pistons were similar to the current production schedule, conditions for the nitrocarburized pistons incorporated a range of processing times from 2–14 hours and temperatures from 510–605°C (950–1125°F). The results of this work were generally consistent with those from an earlier study involving the use of Navy C-ring specimens. For both the Navy C-rings and torque converter pistons, the nitrocarburizing process gave rise to lower part distortion, but resulted in overall lower compressive residual stress values than in the carbonitrided steel.

In this paper, we surveyed the development of maximum-entropy clustering algorithm, pointed out that the maximum-entropy clustering algorithm is not new in essence, and constructed two examples to show that the iterative sequence given by the maximum-entropy clustering algorithm may not converge to a local minimum of its objective function, but a saddle point. Based on these results, our paper shows that the convergence theorem of maximum-entropy clustering algorithm put forward by Kenneth Rose et al. does not hold in general cases.