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In present work, Fields Activated Sintering Technology (FAST), has been applied to successfully sinter the high-entropy alloy (HEA) samples. Based on the analysis of the microstructure, relative density and microhardness of the sintered HEA samples, the influence of sintering temperature and pulsed magnetic field treatment (PMT) has been investigated. In terms of performance, HEA samples fabricated using PMT-powder sintering exhibit superior properties compared to UT-powders. Regarding elemental distribution, pre-treating the powders with a pulsed magnetic field can enhance the uniformity of the alloyed powder components. Furthermore, elevated sintering temperatures have been observed to substantially accelerate the densification process, thereby improving the relative density of the sintered samples.

Pulsed magnetic field treatment, as a novel, quick and environmentally friendly post-processing approach can directly modify the coated tools without causing damage. This study examined the wear performance of the TiAlSiN-coated cemented carbide block specimens treated by the pulsed magnetic fields in both dry friction and cutting fluid friction. The findings show that TiAlSiN coating block specimens subjected to pulsed magnetic fields exhibit better wear resistance in both friction conditions. The wear rate of the coating decreases by 21.49% in a dry friction environment, and the friction process becomes more stable while the wear width of the coating decreases by 4.60% in the cutting fluid friction environment. In addition, the nano-indentation tests show that the hardness and elastic modulus of the coating increases by 6.58% and 5.64%, and the coating binding force increases by 15.27% after the treatment.

In this study, we performed electric pulse treatment (EPT) on the cold-deformed 316L stainless steel. The effects of EPT on the temperature rise characteristics, tensile properties and microstructure of cold-deformed 316L SS were investigated. The results show that changes in current density have a significant effect on the surface temperature and tensile properties. Compared with the UT samples, at a current density of 44 A/mm2, the elongation after fracture reached a peak of 39.8% (the enhancement rate is 14.4%), while the ultimate tensile strength of all the EPTed samples shows no significant change. Interestingly, although the sample experienced an increase in temperature during the EPT process, the phase composition and grain structure remained unchanged significantly. This implies that the improvement in the ductility of the samples may be attributed to the reduction of micropores. The present research provides new light to the enhancement of ductility of cold-deformed 316L stainless steel.

Due to the progress of science and technology in various countries around the world, the problem of marine microplastics makes it impossible to continue ignoring them. Due to the incomplete knowledge of the hazards in microplastics and the lack of attention, research in this field is very scarce at present. This paper provides a comprehensive summary of research related to marine microplastics. Firstly, it introduces in detail the sources and classifications of marine microplastics and their migration process in the marine ecosystem. Then the hazards of microplastics to the marine ecosystem are divided into two parts: the impact on marine organisms and the impact on the marine environment are elaborated in detail. Finally, a series of management measures are proposed according to the hazardous characteristics of microplastics. It is hoped that this paper can contribute to the development of marine microplastic management in a better direction.

Based on the analysis of the multi-mode data of ship mechatronics and the new human-computer interaction regulations for safety driving, a new safety driving regulation based on multi-mode data is put forward. The new regulations for ship safe driving use mechanical and electrical data to form small-world data interconnection. Artificial intelligence and human-computer interaction operation information are used to integrate and communicate, and human-computer interaction data are incorporated to standardize driving behavior to integrate historical driving data, and finally, the standardized automatic self-driving is formed. The new human-computer interaction regulations formed by the safe driving system make it possible to solve and optimize the ship safe driving mode.

A calibration method of indication error of grade III standard metallic scale based on length measuring machine is proposed. The existing length measuring machine is reformed to realize the calibration of the indication error of grade III standard metallic scale. According to the proposed calibration method, the evaluation model of measurement uncertainty is established, and the source of uncertainty is analysed. The expanded uncertainty is less than one third of the maximum permissible error specified in the verification regulation, which verifies the feasibility and effectiveness of the calibration method.

A straightness calibration method of straight edge working face based on electronic level is proposed. According to the proposed calibration method, the evaluation model of measurement uncertainty is established, and the source of uncertainty is analysed. The expanded uncertainty is less than one third of the maximum allowable error required by the calibration specification, which verifies the feasibility and effectiveness of this calibration method.

As global warming, climate variability becomes more and more extreme, and the frequency and intensity of extreme weather events are also increasing. Climate change has changed the hydrological cycle, and its change trend has put forward a severe test for the management of world water resources. Climate change has effects on several components of the water cycle, including precipitation, evapotranspiration, runoff, snow and snow cover, glaciers, and frozen soil. This essay analyses the vulnerability of California's various systems to climate change. California's water cycle model is particularly vulnerable to global climate change. In the past hundred years of California, the average precipitation has decreased with fluctuation; the average temperature has increased; extreme weather phenomena have occurred frequently; the evaporation of the water surface has decreased gradually; the temporal and spatial distribution of runoff has changed greatly; and glaciers have accelerated retreat. California's hydrological cycle is consistent with global water cycle change but also exhibits more complicated regional characteristics, with large spatial differences among watersheds.

COVID-19 has been recurrent for the last three years, the competition in the e-commerce live broadcast market of ‘more, faster, better and more economical’ is becoming increasingly fierce. The Tiktok app as a typical e-commerce live broadcast platform that urgently needs to improve user stickiness to stabilize traffic. Based on the survey of users, this paper explores the influencing factors of user stickiness of e-commerce live broad-cast platform according to CAC theory, and uses SPSS software to test the obtained data. Studies have shown that perceived interaction positively affects emotional attachment, and emotional attachment positively affects user stickiness, perceived interaction can be divided into user control, connectedness, responsiveness, and entertainment, emotional attachment can be divided into platform identity and platform affection. Based on the research conclusions, reasonable suggestions are put forward for e-commerce live broadcast platform.

Under the background of global warming and energy crisis, exploring the new relationship between architecture and climate has always been a hot spot in the construction industry. Thus, a new design pattern “meteorological architecture” guided by a localized meteorological condition is developed. The paper starts with the distinction of the concepts of “meteorology” and “climate” to explains the connotation of “meteorological architecture”. Through the analysis of current theories and practices related to meteorological architecture, a new principle of architectural space division and architectural form generation logic have been summarized. Finally, the enlightening effect of meteorological architecture on other fields is proposed.

In recent years, a kind of mulberry pests which were known as the mulberry gall midge Cotarina sp. in different mulberry planting areas occurred popularly in China. This study aims to screening high efficacy and low toxicity insecticides for controlling Cotarina sp.. The current study can help understand integrated pest management (IPM) of Cotarina sp. by scientific and reasonable insecticide use. Field experiment was carried out to investigate eight insecticides, treated with 3 concentration gradients. The result shows that Imidacloprid, Thiamethoxam, Cyromazine, Bifenthrin and Cypermethrin·Profenofos had high control effect on the mulberry gall midge.Their pesticide residues were all less than Chinese Standard GB2763-2016, which means that they were feasible to control this pest. This paper shows that, to control Cotarina sp. in fruit mulberry production, 10% Imidacloprid WP with 2000~3000 dilution and 25% Thiamethoxam WDG with 1500~2500 dilution and 80% Cyromazine WDG with 1500~2000 dilution are the best. 2.5% Bifenthrin EW with 1000~1500 dilution and 440g/l Cypermethrin·Profenofos EC with 1000~2000 dilution should be used by selection. However, Bifenthrin or Cypermethrin·Profenofos cannot be used in mulberry field for both fruits and leaves, so as to avoid causing silkworm poisoning.

As demands on miniature products increase significantly, a rapid prototyping and production system for highly flexible and cost-efficient production of micro components made from a wide range of materials is needed. In present work, the Micro-forming Fields Activated Sintering Technology (Micro-FAST) with the coupling effects of electrical and pressure fields as the dominant driving force, has been proved to be very successful in the fabrication of the nearly full-density micro-cylinder parts from WC-8Co-xTi-nC powders (x=4, n=2 or x=6, n=0). The influence of heating rate and composition of titanium and carbon has been investigated. Based on the analysis of the relative density, microstructure and mechanical properties, high density (up to 99.7%), fine grain sizes and good mechanical properties could be obtained by Micro- FAST to sinter WC-TiC-Co Cemented Carbide bodies under a low sintering temperature (1200 ℃).

The purpose of the paper is to research the vertical bearing capacity and settlement idiosyncracies of prestressed concrete piles. In-situ experiments, which was carried out by anchor-pile beam counterforce device, and numerical analysis methods was adopted as research methods on 3 tested piles. Mohr-Coulomb model was employed as the constitutive model of soil mass and isotropic elastic damage model as the constitutive model of piles to analyze its yield functions. Furthermore, the basic idea of modelling large deformation problems was analyzed based on Finite Difference Method (FDM). The comparison results was obtained in the paper and it suggested that the simulated data is highly identical with the experimental ones. Load-settlement curve basically presents a quadratic function form.

Nowadays Industrial Control System (ICS) is becoming more and more important in significant fields. However, the using of the general facilities in these systems makes lots of security issues exposed. Because there are a number of differences between the original IT systems and ICSs. At the same time, the traditional vulnerability scan technology lacks the ability to recognize the interactions between vulnerabilities in the network. ICSs are always in a high risk state. So, this paper focuses on the vertex polymerization of the topological vulnerability analysis. We realized a topological analysis method oriented ICSs on the basis of achievements at home and abroad. The result shows that this method can solve the problem of the complex fragility correlation among industrial control networks.

In this study, porous NiTi alloys have been successfully produced by fields-activated micro-sintering and forming technology under the pressure of 75 MPa at 1100∘C. The effects of soaking time on the porous NiTi alloys were investigated by analysing porosities, microstructures, and phase compositions of the produced alloys. The porosities of 41.2%, 38.8% and 47.2% are achieved at the soaking time of 2 min, 6 min and 10 min respectively. SEM examinations show that the pore size is varied with the soaking time and X-ray diffraction studies reveal that the main phases are NiTi, Ni3Ti and NiTi2.

Finite element simulations have been conducted to investigate the heat distribution between the particles from contact resistance and current density during the Micro-forming Fields Activated Sintering Technology (Micro-FAST). Results of effect for the arrangement modes of powder particles (Series connection and parallel connection) showed that the electro-heat focusing could be attributed to the remarkable difference of contact resistance between the particles.

For the purpose of extensive utilization of powder metallurgy to micro/nano- fabrication of materials, the micro gear was prepared by a novel method, named as micro- forming fields activated sintering technology (Micro-FAST). Surface-cleaning of particles, especially during the initial stage of sintering, is a crucial issue for the densification mechanism. However, up to date, the mechanism of surface-cleaning is too complicated to be known. In this paper, the process of surface-cleaning of Micro-FAST was studied, employing the high resolution transmission electron microscopy (HRTEM) for observation of microstructure of micro-particles. According to the evolution of the microstructure, surface-cleaning is mainly ascribed to the effect of electro-thermal focusing. The process of surface-cleaning is achieved through rearrangement of grains, formation of vacancy, migration of vacancy and enhancement of electro-thermal focusing.