Lanthanum oxide was introduced to molybdenum powder by liquid-liquid doping and liquid-solid doping respectively. Mo alloys were prepared by powder metallurgy technology. The size distribution and feature of dopant particles and the fractographs of Mo alloys were investigated by TEM and SEM respectively. The results indicated that liquid-liquid doping method is favorable for refining and dispersing particles uniformly in matrix. Fracture toughness of Mo alloys prepared by liquid-liquid doping showed better results than that of liquid-solid doping. Furthermore, the influences of the size distribution of on properties of Mo alloys was discussed by dislocation pile-up theory.

The ultrahigh pressure process for synthesizing diamond grits is due to make a quantum leap: the raw materials will incorporate diamond seeds with a predetermined pattern. The result is doubling the diamond yield with a narrower size distribution. Moreover, the shape of diamond crystals can be precisely tuned. For example, diamond octahedra or diamond cubes, that are not available today, can be mass-produced. The new technology is now being implemented worldwide so the future diamond grits will have improved quality at reduced prices.

This research mainly focuses on the development of sinter brazing technology for improving the process related to belt pulley made by sinter hardening. As the machine process of belt pulley takes up more than half of the total manufacturing hours, we propose changing the process to pulley groove brazed and bonded with pulley disc by applying sinter brazing to belt pulley. With the new process, the belt pulley is expected to reduce manufacturing cost to 70% of the original process by applying the sinter brazing technology; and the belt pulley bound by sinter brazing only loses 10% bonding strength compared with the original process.

Tungsten heavy alloys with different ratios of Mo and Ni-Fe matrix were liquid-phase-sintered to investigate their microstructural evolution. Results indicated that increased Mo in the alloy promoted the formation of a (W,Mo)(Ni,Fe) type intermetallic compound in the furnace-cooled condition. It was a monoeutectic reaction when the added Mo content was higher than 49at.%, or a eutectic reaction when this value was between 37at,% to 49at.%. When Mo was added between 25at.% to 37at.%, the precipitation of the intermetallic compound took place by either a eutectoid or peritectoid reaction.

Vacuum carbonization of nanometer tungsten powder was investigated in a simple designed apparatus. An X-Y recorder was used to plot differential thermal analysis (DTA) curves to determine starting temperature of carbonization of four samples with different specific surface area. The product was detected by X-ray Diffraction (XRD) and small angle X-ray scattering (SAXS). The results show that finer tungsten powder has lower starting temperature of carbonization. Tungsten powder, which BET surface area is , is completely carbonized to tungsten carbide at , although the starting temperature is . Particle grows sharply before carbonization.

The linear intercept (LI) method was used to quantitatively measure the intercepts of WC grains in nano-grained WC-10Co hardmetal. When the surveyed intercept numbers of WC grain exceeded 200, the statistic data for the mean grain size of WC were reproduced. The discriminative minimal grain size of used LI method was 12 nm; the maximum intercept of WC grain was 109 nm; the average intercept of WC grains was 45 nm and the corresponding 3D mean grain size of WC was 70 nm which is agreeable with the XRD outcome.

The thermal dissipation performance of sintered heat pipes is usually determined by the capillarity and permeability of the Cu powder wicks. Since the capillary provided by the Cu powder is usually large enough to draw water from the condenser end to the evaporator end, the permeability has become the controlling factor. In this study, Cu powders with different particle sizes and shapes were loosely sintered, and their permeabilities were compared. The results show that more complicated shapes, finer particle sizes, lower porosities, and rougher pore surfaces give lower permeability and thermal dissipation.

Gas-permeable metal die materials are developed using tool steel powder, packed in a mold having the insertion of orthogonally arrayed polymer wires. Linear gas-permeable channels in orthogonal array are thus developed by the burning out of the polymer wires, which yield a microstructure with wear resistance value and air permeability much larger than those of the conventional gas-permeable die material.

Under the background of economic globalization, the trade between countries in the world is increasing rapidly. Under the rules of WTO, the tariff rate of trade barriers is decreasing, but on the other hand, nontariff barriers are increasing. especially Compared with tariff barriers, green trade barriers have a greater impact on agricultural trade. Therefore, the negative impact of green trade barriers on agricultural products trade is a problem worthy of attention and urgent response in the future agricultural products trade between China and South Korea. Firstly, this paper analyzes the meaning and characteristics of green trade barriers, introduces the current situation of agricultural products trade between China and South China, analyzes the influence of Korean trade barriers on’s agricultural products export trade, and on this basis, forms countermeasures to promote Chinese agricultural products export to South Korea. The research of this paper has certain guiding significance for promoting Chinese agricultural export trade to South Korea.

The rapid development of information technology has continuously promoted the informatization of education. Information technology has had a profound impact on education, and teachers are also facing new challenges. TPACK has become one of the important qualities of teachers in the information age. TPACK theory emphasizes the intersection and deep integration of technology, subject knowledge, and pedagogical knowledge. Through the investigation and study of current primary school teachers’ TPACK, it is found that primary school teachers generally lack the deep integration of technical knowledge and subject teaching content. Research on strategies to improve TPACK for primary school teachers.

Foodborne disease caused by pathogenic bacteria is one of main concerns in food industry. To supply safe food products, chemical and thermal intervention technologies have been widely applied in food industry, however these treatments have their own limitations. The concept of biopreservation has recently received increased attention in response to industrial and consumer demands. The biopreservation technologies mainly include bacteriocin, bacteriophage, bacteriophage-encoded enzymes, and endolysins. Among them, bacteriocins have been widely recognized as a main biopreservative and have also been most studied. Bacteriocins, mainly consisting of antibacterial peptides, may have bactericidal or bacteriostatic effect which could prolong the shelf-life as well as maintain safety of foods. This review article offers a brief research trend about bacteriocins, focusing on microbial food safety. The antimicrobial mechanism of bacteriocins has been discussed and some efforts to inactivate foodborne pathogens have been analyzed in this review article. The challenges facing the application of bacteriocins have also been evaluated. Thus, this review will provide insights for researchers working in bacteriocin as well as industry personnel looking for a new method for fighting foodborne pathogens.

Purpose: This study examines the impact of individual reciprocal preferences on coalition formation. The reciprocal model considers a player’s own payoff, the player’s perception of others’ payoffs, and others’ perceptions of the player’s payoff. Research design, data and methodology: A reciprocal model is built to illustrate how reciprocity influences individual decisions in a coalition game and its formation. The prediction is examined with experimental evidences from a dictator game and a membership game. Results: The theoretical result suggests that the coalition formation could be unstable due to negative reciprocal kindness. The experimental findings support that negative reciprocal kindness could lead players participating in a coalition, no matter their dominant strategies are. When subjects were essential to make contributions to a coalition, they were more likely to cooperate if they were treated badly. In contrast, when subjects were unnecessary, the reciprocal kindness could enhance cooperative tendencies. Conclusions: This study reveals that the reciprocal behavior could influence individual decisions and reshape the coalition formation. In terms of policy implications, this study has shown that coalition formation could be reshaped by reciprocal prefe rences. Due to the strategic and complicated decision process in an interactive environment, a comprehensive investigation of factors would be required in a climate coalition in practice.

The paper proposes a knowledge innovation performance model by the dynamic data envelopment analysis with slacks-based measure approach for evaluating the effectiveness of 30 regional knowledge innovation activities in China from 2010 to 2016. In recent years, China has paid more attention to knowledge innovation activities, as central and local governments have pushed on with their innovation projects by lots of investment whatever the difficulties may be. Decision-maker is usually interested in judge its knowledge innovation performance relative to target benchmark by exploring whether one provincial administration region performs better among others and/or if the growth of economy will be benefited greatly by the knowledge innovation activities. To acquire the managerial insight about this issue from a comprehensively designed performance evaluation model, knowledge innovation activity is conceptualized as an intertemporal production process. Invention patent and regional gross product are imposed on desirable outputs, highlighting the need for knowledge economy. The empirical result shows that knowledge innovation has a positive effect on economic development. At the same time, decision-maker should be interest in the economic effect of patents’ type and quality. The government should then encourage new technical applications with greater commercial value from a market-oriented perspective, in order to benefit the most from the innovation process in the short-run.