Research on Heredity of Coarse Ferrite Grains

The changes in austenite grain size of the specimens with coarse ferrite grains under different heat treatment process were investigated. The focus was on studying the effect of annealing on refining coarse ferrite grains, as well as the influence of the ferrite grain size on the main technical indicators of gas carburizing. The results show that coarse ferrite grains may not necessarily cause the coarse austenite grains, but may result in mixed austenite grains. After annealing treatment, the coarse ferrite grains can be significantly refined and homogenized. Moreover, the coarse ferrite grains have no significant effects on hardness and intergranular oxidation of gas carburizing

The Influence of Dry or Wet Activating Process to the Electrochemical Features of Biowaste Carbon

The utilization of biowaste to the activated carbon (AC) as electrode material is conducive to alleviating the energy crisis and promoting the high value-added. The popular KOH activation has been applied for years, but rare report clarified the difference of dry and wet activation, with which the batch producing technique could be different. Here nitrogen doped hierarchical AC was derived from wood chip by a wet or dry KOH activation. The surface area, framework structure and surface feature were characterized to reveal the effect of wet and dry activation. 1.44 at% of nitrogen doped AC was made by dry KOH activation, which was higher than the AC derived from wet KOH activation with 1.36 at% of nitrogen. Their electrochemical properties were investigated in 6 mol L-1 of KOH, the capacitance of wAC was 401 F g-1 at 0.5 A g-1, but dAC possessed a capacitance of 215 F g-1. These indicated that AC obtained by using wet KOH activation displayed a potential application in energy field

High Temperature Rheological Performance of Graphene Modified Rubber Asphalt

To elucidate the high temperature rheological capability of graphene modified rubber asphalt， three contents of graphene and crumb rubber were prepared by a combination of mechanical agitation and high speed shearing machine ,then used dynamic shear rheological test (DSR) and multiple stress creep recovery (MSCR) tests to evaluate. The hardness and softening point with rotational viscosity of samples raised with the addition of graphene, especially the addition of 0.04%. Dynamic shear rheological test revealed that the dynamic shear modulus G*, rutting factor G*/Sin δ, and zero shear viscosity (ZSV) of graphene-modified rubber asphalt were greatly influenced along with graphene-increased, on the contrary, phase angle δ which characterize the viscoelastic ratio of asphalt decreased. Multiple stress creep recovery (MSCR) tests showed that the graphene-enhanced rubber asphalt had high-temperature stability through non-recoverable creep compliance (Jnr). Based on these findings, graphene-modified rubber asphalt binders with the addition of 0.04% graphene had good viscoelastic properties as well as high temperature rutting resistance performance. In the meantime, G*/Sin δ, ZSV, and Jnr100, Jnr3200 have good correlation, which can reveal the excellent high-temperature stability performance of asphalt

Research and Application of Recycled Concrete Technology in Prefabricated Buildings

The utilization of waste concrete as a raw material for recycled concrete in the domain of prefabricated components is garnering greater interest. This paper delineates and examines the concept, categorization, methodologies of preparation, applicable sectors, and evaluative metrics of recycled concrete technology, highlighting its prospective benefits. Nonetheless, for the successful integration of recycled concrete technology into prefabricated component applications, it is imperative to systematically enhance its physical, mechanical, and attributes, as well as its environmental efficacy. Moreover, to foster the continued advancement of recycled concrete technology, innovative initiatives, standardization, educational programs, demonstration projects, and collaborative efforts are crucial to promote broader adoption and realize improved outcomes within the realm of prefabricated components. In conclusion, recycled concrete technology is poised to play a pivotal role in prefabricated construction, offering robust support for propelling the construction industry towards a sustainable future

Residual Film Pollution in the Eighth Division of the Xinjiang Production and Construction Corps

This study investigated the residual film content and distribution at different soil depths in the Eighth Division of the Xinjiang Production and Construction Corps. Before spring plowing in 2019, representative fields in four areas (Anjihai, Shihezi suburbs, Mosuowan and Xiayedi) were selected for residual film collection. The average content of residual film in the Eighth Division was 104 kg/ha. The residual film content in the four areas decreased in the order Anjihai ＞ Shihezi suburbs ＞ Mosuowan ＞ Xiayedi. The average amount of residual film collected from cotton fields was greater than that from corn fields. Residual film content in the cotton field at soil depths of 0～10 and 10～30 cm was higher than that in the corn field, whereas the residual film content at a 30–50 cm soil depth in the corn field was higher than that in the cotton field. The results showed that farmers do not consider the long-term benefits, the high cost and short time of recycling, and the easy recycling of surface residual film. The shallow that the higher content of residual film, the less water in the soil of cotton. The same time, the results showed that the quantity of residual film in cotton field had greater influence on cotton quality

The Effect of Graphene Oxide on Mechanical Properties of Cement Mortar

Cement is widely used in engineering applications, but it has both the characteristics of high brittleness and poor bending resistance. In this paper, the effects of different amounts of graphene oxide on the flexural strength and compressive strength of cement mortar were studied by doping a certain amount of graphene oxide with cement mortar, and the strengthening mechanism of graphene oxide on cement mortar was obtained through microstructure detection. It is found that graphene oxide has a significant enhancement effect on the macroscopic mechanical properties of cement mortar, and graphene oxide provides nano-nucleation sites and growth templates for cement mortar, accelerates the hydration process, reduces the voids between hydration products, greatly increases the compactness, and improves the macroscopic properties of cement-based materials

Preparation and Properties of Bilayer Composite Materials of Cu-coated Fe and CuSn10

Bilayer composite materials of Cu-coated Fe and CuSn10 containing 0%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50% Cu-coated Fe were prepared in mesh belt sintering furnace. Microscopic pore morphology of materials was observed, bending strength was tested. Results show that, There is a good bonding between Cu-coated Fe and CuSn10, with the increase of Cu-coated Fe content from 0% to 50%, bending strength of bilayer composite materials increases

Development and Application of Modern Building Ceramic Materials

With the increasing demand for sustainable building design, modern building ceramic materials are one of the key factors driving innovation and development in the field of architecture, thanks to their excellent performance and environmentally friendly properties. The aim of this study is to provide an insight into the development and application of building ceramic materials in modern architecture, and to assess the contribution of material innovation to architectural design and sustainability goals by synthesising and analysing recent technological advances and case studies in this field. This study adopts a systematic literature review approach to screen and analyse a large number of academic articles and practical project reports on material innovation in building ceramics. Comparative analyses of different material properties, advances in production processes and the effects of their application in real building projects reveal the potential of building ceramic materials to improve the energy efficiency, extend the service life and enhance the aesthetic design of buildings. The findings show that the environmental and energy issues facing traditional building materials, such as improved thermal efficiency and a reduction in the overall carbon footprint of buildings, can be effectively addressed through the use of new building ceramic materials and technologies. In addition, the innovative use of architectural ceramics provides architects with more design flexibility, enabling them to create architectural works that are both aesthetically pleasing and functional. In the concluding section, the paper highlights the importance of continuing to explore technological innovations in building ceramic materials and how these innovations can contribute to a more sustainable and environmentally friendly building industry. Future research should further explore new areas of application for ceramic materials and how interdisciplinary collaboration can accelerate the practical application of these material technologies

Study on Gas Explosion Characteristics in Urban Utility Tunnels

In order to study the effects of three factors, namely, premixed gas concentration, number of pressure relief ports and number of obstacles, on the overpressure characteristics of gas explosion and flame structure of gas chambers in utility tunnels, in this paper, a small and narrow experimental platform for gas explosion was constructed to study the evolution mechanism and law of the kinetic characteristics and flame behavior of gas explosion in utility tunnels, with a view to revealing the special influencing mechanism of the overpressure characteristics and flame behavior of gas explosion in utility tunnels. The results show that in the methane concentration of 9.5% when the explosion overpressure reaches its peak, and at the same time by the utility tunnel long and narrow restricted space, the explosion generated by the precursor shock wave along with the flame compression wave were superimposed on both ends of the pipeline back and forth for many times so that the overpressure waveforms are cyclic oscillatory trend, increasing the explosion hazards; compared with the closed conditions, the relief port on the overpressure characteristics of the significant impact of the maximum decrease of 57.7%, when the frequency of overpressure oscillation is reduced, the gas explosion generated by the overpressure damage is reduced; the presence of obstacles significantly affects the flow field, accelerates the flame propagation and leads to greater overpressure peaks and overpressure oscillations. The conclusions of the study can provide a basis for the safety of natural gas in utility tunnels

Research Progress of High Entropy Ceramic Materials

High-entropy materials (HEMs) have better mechanical, thermal, and electrical properties than traditional materials due to their special "high entropy effect". They can also adjust the performance of high entropy ceramics by adjusting the proportion of raw materials, and have broad application prospects in many fields. This article provides a review of the high entropy effect, preparation methods, and main applications of high entropy ceramic materials, especially exploring relevant research on high entropy perovskite ceramics. It is expected to provide reference for the promotion of scientific research and the development of further large-scale applications of high-entropy ceramic materials