Similarities of Expressing Disagreement by Chinese and American College Students

To explore the ways in which modern Chinese and Americans express their disagreement in intercultural communication and to reveal the reasons for their usage from the perspectives of sociolinguistics and persuasive communication and with the rapport management as the theoretical framework, this paper focuses on the discourse analysis of implicit disagreement expressions between 11 pairs of Chinese and American college students. The analysis of the four-month communication corpus reveals that Chinese and American students tend to use implicit disagreement when they disagree with each other and there are more similarities than differences in the usage of implicit disagreement. The reasons are related to their respective cultures and globalization. In addition, students use more implicit disagreement in the latter stage of their communication since these students are attending the course Intercultural Communication while interacting with each other. Last but not the least, the study suggests that the learning mode of pairing up Chinese-American students seem to be able to greatly promote their intercultural communication competence

Chemical composition of the volatile oil of Chenopodium ambrosioides L. from Mianyang in Sichuan Province of China and its sub-chronic toxicity in mice

Purpose: To determine the chemical constituents of the volatile oil of Chenopodium ambrosioides L. from Mianyang in Sichuan Province of China, and assess the sub-chronic toxicity of the volatile oil in mice.Methods: The volatile chemical components were analyzed by gas chromatography-mass spectrometry (GC-MS). Sixty Kunming mice were divided into six groups of ten mice each. One group served as control (no treatment), two groups were orally administered ρ-cymene at doses of 3 and 7 mg/kg, respectively, for 27 days, while three groups received the volatile oil at doses of 10, 25 and 40 mg/kg, respectively, for the same duration. Sub-chronic toxicity in the mice was evaluated by observing their general behavior, measuring serum levels of aspartate transaminase (AST) and alanine transaminase (ALT), evaluating liver, heart, kidney and thymus indices, and assessing the histological morphology of the organs.Results: The volatile oil contained 14 chemical components, of which α-terpinene and ρ-cymene accounted for 32.89 and 24.25 %, respectively. The volatile oil caused significant (p < 0.05) increase in liver index, and serum AST and ALT levels, and also induced distinct morphological changes in mouse liver, heart and kidney.Conclusion: The main volatile components of the oil are α-terpinene and ρ-cymene. The volatile oil showed dose-dependent toxicity in mice, thus lending some support for the safe use of C. ambrosioides in traditional medicine. Keywords: Chenopodium ambrosioides, Volatile oil, Oral toxicity, AST and ALT, Histopathological change

Exploring the Applicability of Building Energy Performance Certification Systems in Underground Stations in China

To improve the energy efficiency of underground metro stations, and in view of the absence of a comprehensive energy performance evaluation system for underground stations, this study introduced building Energy Performance Certification (EPC) tools into underground stations and conducted a comparative analysis of their applicability. The findings indicated that due to the unique characteristics of underground stations, China’s current EPC system was inapplicable to them. Specifically, (1) for basic items, although evaluation methods were available, due to the limited energy use data for the statistical method, the self-reference method was preferred, but its calculation encountered issues with missing reference values; (2) for prescribed items, the emphasis should be placed on the energy efficiency requirements of energy use systems rather than those of the thermal performance of envelopes; (3) for alternative items, the energy recovery measures related to the heat dissipation of trains and the piston wind should be addressed. Furthermore, a case study was conducted for verification of the proposed energy evaluation method, and the EPC system was updated based on the results of the comparison. The authors hope that this study will help improve China’s energy evaluation methods for underground stations and serve as a reference for expanding the EPC system to include public transportation buildings

Influence of external heat sources on volumetric thermal errors of precision machine tools

Volumetric accuracy is susceptible to thermal gradient caused by internal heat source (IHS) and external heat source (EHS). A temperature-structure multi-step calculation method is presented to investigate the influences of EHSs on volumetric thermal errors of precision machine tools. The temperature and structure of the machine tool are simulated first, and then, the volumetric thermal errors are calculated using multi-body theory method. Simulations are completed to study the effects of different EHSs on a machine tool, and series of validating experiments are carried out to verify the modeling method. The test results in specific position and working condition revealed that EHSs contribute 53, 21, and 68% of thermal deviations in X, Y, and Z directions individually. It is illustrated that the EHS is an important factor affecting the volumetric accuracy of precision machine tools. The methods provided in this paper are valuable for machine tool designers to evaluate the EHS effects on volumetric thermal errors during designing process; furthermore, some insulating measures are suggested to improve the accuracy and accuracy stability of precision machine tools by reducing the EHS influences

A Review of Selective Laser Sintering of Wood-Plastic Composites

Eco-friendly wood-plastic composites were firstly proposed to be used as the raw materials of rapid prototyping in 2002, and successfully applied in Selective Laser Sintering (SLS) two years later. These composites were mixed by different kinds of wood powder, plastic powder and other additives. Different from polymer, ceramics, metals and their composites, wood-plastic composites are new types of sustainable and low-price feedstock of SLS. This paper presents the development of the research of wood-plastic composites applied to SLS over the past decade. It contains the preparation and characterizations of wood-plastic composites, the study of temperature fields and molecular dynamics simulation of sintering wood-plastic composites, the effects of processing parameters on the forming accuracy and mechanical properties of sintered parts, and the post-treating process of wood-plastic composite parts. At last, it introduces the application fields of laser sintered wood-plastic composites parts.Mechanical Engineerin

Characteristics and assessment of the electricity consumption of metro systems: A case study of Tianjin, China

Owing to the complexity of metros, the energy consumption characteristics of metro systems exhibit variability and the energy‐saving management of the systems encounters challenges. To encapsulate the essential characteristics of energy usage and to objectively assess the energy performance of metro systems, this study presents a generalized framework and applies it to a case study conducted in Tianjin. The study also employs correlation analysis to investigate the applicability of the indicators relevant to ridership. The results indicate that the monthly traction electricity consumption exhibits slight variation, while station electricity usage demonstrates substantial fluctuation with seasonal changes. For Tianjin Metro, the passenger factor hardly shows any effect on the electricity use of metro lines. The median value of traction electricity use is approximately 2.0 kWh/(car‐km) and that of the average annual station electricity use of underground lines ranges from 95 to 155 kWh/m2. The emission from the traction sector is 12.2 kgCO2/(vehicle‐km) and from the station sector is 118.6 kgCO2/m2. The study also identifies the energy‐intensive lines of the Tianjin Metro and compares the energy utilization among various global metro systems. The authors hope that this study can help shed light on the assessment of the energy status of metro systems and serve as a source of information for other City‐Metros to implement energy‐saving management

N, S co-doped biomass derived carbon with sheet-like microstructures for supercapacitors

Abstract(#br)In this study, N, S co-doped bamboo fiber derived carbon has been prepared when K 3 Fe(CN) 6 and thiourea are selected as graphitization catalysis and dopant, respectively. The derived carbon possesses a large S BET , suitable graphitization degree, excellent conductivity and wettability of electrolyte, and particularly, it exhibits a unique sheet-like microstructure derived from the layer stripping of gas produced by thiourea pyrolysis, and these microstructure features are very beneficial for energy storage. Typically, the derived carbon displays a high specific capacitance of 328 F/g and an acceptable rate capability of 61.3% at 15 A g −1 in three-electrode systems. Meanwhile, the derived carbon-based coin-type symmetric supercapacitors are assembled in an aqueous electrolyte and an ionic liquid electrolyte, respectively, and they all show a considerable synergetic energy-power output performance (21.2 Wh kg −1 at 454 W kg −1 in aqueous electrolyte, and 61.6 Wh kg −1 at 300 W kg −1 in ionic liquid electrolyte), indicating the potential application of the derived carbon in supercapacitors