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The purpose of this paper is to study the variations of composition and properties of the passive film on 316 L stainless steel surface in 80°C, 0.5 mol L-1 H2SO4 + 2 mg L-1 NaF solution, is helpful to understand the mechanisms of corrosion resistancethe of plated Pd on 316 L ss.

The variations of composition and properties of the passive film on 316 L stainless steel surface in 80°C, 0.5 mol L-1 H2SO4 + 2 mg L-1 NaF solution after connected to Pd electrode were studied with methods of potential monitor, X-ray photoelectron spectroscopy analysis and electrochemical impedance spectrum (EIS) measurement.

By connecting to a Pd electrode, the potential of the SS sample increased from the active region to the passive region. By connecting to the Pd electrode, the contents of Cr, Cr(OH)3 and Fe3O4 in passive film increased obviously. With increased Pd/SS area ratio, the Cr(OH)3 content in passive film increased but the Fe3O4 content changed little. The results show that after connecting to Pd the corrosion resistance of the passive film on 316 L stainless steel increases obviously, which may be attributed to the more compact passive film because of higher Cr, Cr(OH)3 and Fe3O4 contents and less point defects in the film.

The effects and mechanism of Pd on passivation of SS was studied.

In order to unravel the evolution of microstructure characteristics and the change of mechanical properties of bituminous mixture in the freezing and thawing environment in cold region, this study starts from macroscopic experiments and analyzes the changes in mechanical properties of asphalt mixtures before and after freezing and thawing in detail. On this basis, the displacement of key particles in the structure of asphalt mixture under the action of external forces (before and after freezing and thawing) is simulated through the combination macroscopic and microscopic methods.

The climate in China exhibits high complexity and diversity, divided into five zones based on the temperature difference from south to north. Considering that the significant effect of geography and natural climate on the design, construction and maintenance of asphalt pavement, the criterion for the road construction at different areas should be highly different.

The results show that the mechanical properties of asphalt mixture greatly decrease due to the influence of freeze-thaw, and the displacement of key particles in the structure of asphalt mixture (several representative particle sizes were selected through experiments) is obviously observed because of the action of external force. By analyzing the variation of several key particle sizes after freezing-thawing cycle, the gradation standard of asphalt mixture aggregate suitable for cold area was obtained. The research results have certain theoretical and practical value for the design and application of asphalt mixture in cold area.

The results show that the mechanical properties of asphalt mixture greatly decrease due to the influence of freeze-thaw, and the displacement of key particles in the structure of asphalt mixture (several representative particle sizes were selected through experiments) is obviously observed because of the action of external force. By analyzing the variation of several key particle sizes after freezing-thawing cycle, the gradation standard of asphalt mixture aggregate suitable for cold area was obtained. The research results have certain theoretical and practical value for the design and application of asphalt mixture in cold area.

In order to explore the damage probability of bridge engineering in the event of earthquake in the construction stages, the analysis method of seismic vulnerability in the construction stages is proposed in this paper.

Based on the joint simulation function of construction stage conditions and seismic response conditions of MIDAS/Civil finite element analysis software, combined with the method of IDA analysis and compared the relationship between demand and capacity.

The research shows that: (1) the average seismic loss in different construction stages varies greatly; (2) the seismic vulnerability varies greatly in different construction stages. The vulnerability of the bridge in stage 6 is determined by the longitudinal direction of bridge. Therefore, during the construction of the whole bridge, we should focus on strengthening the disaster and loss prevention strategy of earthquake insurance in the longitudinal direction of bridge. (3) The application of the secondary dead load mainly affects the fragilityin the longitudinal direction of bridge, but has little effect on the fragility in the transversal direction of bridge.

This paper is to explore the seismic vulnerability of a typical simply supported continuous bridge during the construction stages, and to trace the entire construction stage of a typical simply supported continuous bridge. According to the characteristics of the system transformation in the actual construction steps, demand-capacity ratios were established based on incremental dynamic analysis (IDA) and performance indicators of moment curvature and stability, and the seismic vulnerability research is carried out for the construction stages prone to earthquake damage. Furthermore, it provides a basis for seismic risk assessment of such bridges in different construction stages.

The purpose of this paper is to investigate the use of mobile assisted language learning (MALL) in vocabulary learning among English foreign language learners in China with a lens on academic major difference. This study hypothesizes that academic majors including Science, Technology, Engineering and Mathematics (STEM) and non-STEM differentiate the learners’ perception of computer self-efficacy (CSE) and MALL learning performance as well as moderate the effect of CSE on language learning performance.

Sample data for this study were collected from 200 university students enrolled in both STEM and non-STEM majors. Under the quasi-experiment, this study had been conducted vocabulary training, pre-test, post-test and a questionnaire. The Statistical Package for the Social Sciences, a statistical analysis technique based on ANOVA and regression were used to analyze the data.

The results support hypotheses that CSE, learning score and satisfaction are rated higher for STEM students than non-STEM ones and indicate the effect of CSE on language learning performance is stronger for STEM students than non-STEM ones in using MALL.

This paper addressed important issues in language learning on the academic major difference. The findings would be the guidelines for educational organizations to motivate and stimulate students with sustainable self-confidence important not only for improvement in students’ language learning achievements and outcomes but also for the advancement of mobile technology in language learning.

This paper aims to check the presence of such relationship in the field. Certain values are at stake for the success of economic behavior. Since the genesis of modern capitalism, a set of beliefs proper of Calvinism (mainly Predestination but also Beruf, inner-worldly asceticism, role of Sects […] ) was said by Max Weber to cause an anxiety about salvation and generate a propensity to economic success as a sign of election. The author argues on the contrary that the Calvinist belief in the Perpetual Assurance of Salvation might cause a sense of self-efficacy able to favor economic success. To observe this in action today, it is crucial to consider the evolution that the Protestant ethic went through migrating first in North America and, finally, through the Protestant revival of China. Wenzhou is called “Jerusalem of China” for its large Protestant community that is also strongly involved in business. Some scholar already pointed out the presence among those entrepreneurs of this Protestant ethic (Yi Xiang, Boss-Christian […]).

The data presented in this comparative qualitative study pertain to ethnographic observations, job-shadowing and interviews done among Chinese Christian and non-Christian entrepreneurs from Wenzhou living in Milan, Italy.

The results show, with some adjustments, the presence of a Chinese version of the Protestant ethic overlapping with several values proper to the Chinese context (Confucianism, lineage, social network). The extension of the study to other cases must be done with caution considering the non-causal justificatory role of the belief.

Successful entrepreneurship involves specific social, cultural and even religious aspects that move beyond mere business strategies.

Internet marketing underground industry users refer to people who use technology means to simulate a large number of real consumer behaviors to obtain marketing activities rewards illegally, which leads to increased cost of enterprises and reduced effect of marketing. Therefore, this paper aims to construct a user risk assessment model to identify potential underground industry users to protect the interests of real consumers and reduce the marketing costs of enterprises.

Method feature extraction is based on two aspects. The first aspect is based on traditional statistical characteristics, using density-based spatial clustering of applications with noise clustering method to obtain user-dense regions. According to the total number of users in the region, the corresponding risk level of the receiving address is assigned. So that high-quality address information can be extracted. The second aspect is based on the time period during which users participate in activities, using frequent item set mining to find multiple users with similar operations within the same time period. Extract the behavior flow chart according to the user participation, so that the model can mine the deep relationship between the participating behavior and the underground industry users.

Based on the real underground industry user data set, the features of the data set are extracted by the proposed method. The features are experimentally verified by different models such as random forest, fully-connected layer network, SVM and XGBOST, and the proposed method is comprehensively evaluated. Experimental results show that in the best case, our method can improve the F1-score of traditional models by 55.37%.

This paper investigates the relative importance of static information and dynamic behavior characteristics of users in predicting underground industry users, and whether the absence of features of these categories affects the prediction results. This investigation can go a long way in aiding further research on this subject and found the features which improved the accuracy of predicting underground industry users.