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This paper proposes an omnidirectional conveyor as a novel alternative to existing omnidirectional conveyors. With a symmetric and compact layout, this new structure ensures consistent kinematics and enhanced flexibility in trajectory planning. The kinematic model of the proposed omnidirectional conveyor is developed and verified through simulation in CoppeliaSim. Four typical classes of trajectories are generated and verified in the simulation environment. Using PID control, the actual trajectories of a package on the conveyor closely match the desired trajectories. In addition, this paper outlines the workspace and corresponding wheel patterns for the conveyor, demonstrating how different supported wheel patterns emerge when packages move across various areas of the conveyor. The discussion extends to fault tolerance and obstacle avoidance, examining the workspace and wheel patterns with one or two omni wheels failed. Furthermore, this paper provides a comprehensive analysis of the feasible desired movements for the packages on the conveyor under the constrained wheel speed. This provides insights and guidance on trajectory planning and design of the conveyor. [ABSTRACT FROM AUTHOR]

This study delves into the impact of digital inclusive finance on environmental pollution, with a specific focus on air pollution. Utilizing data from 265 Chinese cities, advanced econometric methods such as the bi-directional fixed effects model, threshold model, spatial Durbin model, and multi-period difference-in-differences model are employed, incorporating a variety of control variables. The empirical findings indicate that digital inclusive finance significantly reduces air pollution. This mechanism chiefly operates through enhancing public environmental consciousness and fostering green technological innovation. The study also uncovers the spatial spillover effect and non-linear characteristics of digital inclusive finance on air pollution, along with its interactive effects with specific policies (e.g., smart city pilot policies and the "major protection, no major development" initiative). Moreover, heterogeneity analysis reveals regional variations in the environmental effects of digital inclusive finance. These insights provide a novel perspective on the relationship between financial technology and environmental protection and offer crucial guidance for policymaking. [ABSTRACT FROM AUTHOR]

Nowadays, low-temperature co-fired ceramic (LTCC) technology has become one of the main forms of manufacturing electronic devices. However, a majority of microwave dielectric ceramics are not suitable as LTCC materials due to their high sintering temperatures. Developing novel LTCC materials with good microwave dielectric properties is extremely urgent. In this paper, an LiF sintering aid was added to Li2Ti0.8(Co1/3Nb2/3)0.2O3 (LTCN) ceramics to explore new LTCC materials. The sintering behavior, microstructure and microwave dielectric properties of LTCN + x wt% LiF ceramics were investigated in detail. The results indicated that the addition of LiF increased the degree of disorder in the LTCN matrix, transforming it from a monoclinic to a cubic crystal system. The ceramics exhibited relatively dense and homogeneous microstructures at the sintering temperature of 950 °C as the LiF doping amount was not less than 2 wt%. By LiF doping, the quality factor (Q × f) value was significantly enhanced due to the improved microstructure. Meanwhile, the temperature coefficient of resonant frequency (τf) of LTCN ceramics was successfully regulated to the near zero value owing to the negative τf characteristic of LiF. Excellent microwave dielectric properties of dielectric constant (εr) = 19.01, Q × f = 144,890 GHz, τf = −1.52 ppm/°C were obtained when the sample doped 3 wt% LiF was sintered at 950 °C for 3 h. Furthermore, the good chemical compatibility of the LTCN-3 wt% LiF ceramic with silver electrodes suggested that the ceramic was a potential material for LTCC applications. [ABSTRACT FROM AUTHOR]

In order to improve wear comfortability and durability of protective clothing for medical use, the washable fabric of protective clothing for medical use was developed. Its protective performance was studied. Four kinds of fabrics for medical protective clothing were prepared by point-type offline composite processing technology with polyimide nanofiber membrane via electrospinning as core barrier layer and woven fabrics as inner and outer layers. The fabric appearance, protective properties, comfortability and mechanical properties before and after washing were tested and analyzed. Results showed that the protective fabrics prepared with polyester/cotton blended woven fabric as outer layer had excellent protective performance, wear conformability and mechanical properties after 20 times washes. It could meet the wash resistant of protective clothing for medical use. [ABSTRACT FROM AUTHOR]

In this paper, nanocrystalline Nd[(Zn0.925Co0.075)1/2Ti1/2]O3 (NZCT75) powders were synthesized through glycine–nitrate combustion method with the intent of reducing the sintering temperature and improving the microwave dielectric properties of NZCT75 ceramics. Phase composition, structure, and morphology of the powders were analyzed by thermogravimetric analysis–differential thermal analysis (TG–DTA), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The XRD results showed that the as-synthesized powder after rapid self-propagating combustion was highly crystallized and was mainly composed of NZCT75 phase and small amount of unknown phase. The unknown phase could be vanished through the calcination process of 600 °C. Compared to solid-state reaction route, a reduction of about 600 °C in the synthesis temperature for pure phase NZCT75 was realized. A large amount of pores with inhomogeneous distribution in size and shape was found from the SEM image of the as-synthesized powder due to the rapid combustion reaction between glycine and nitrates. The TEM study revealed that the average particle size of the calcined powder is around 31.9 nm. The bulk sample prepared by the nanosized powder could be sintered to 98.8% of the theoretical density at 1250 °C, reducing about 160 °C more than the solid-state reaction method. Meanwhile, excellent microwave dielectric properties of NZCT75 ceramics presented a dielectric constant of 37.17, a quality factor of 257,600 GHz, and a temperature coefficient of resonant frequency of – 29.48 ppm/oC. This study develops a facile approach to synthesize nanocrystalline powder for a promising application in microwave dielectric ceramics. [ABSTRACT FROM AUTHOR]

The main content of FZ/T 64083--2021 Fabrics for Protection against Molten Metal Splash was analyzed. Similarities and differences between the standard and ISO 11612--2015 standard were compared and analyzed, new assessment indicators and test methods of the standard were listed. The standard filled the standard blank in the field of high-temperature molten metal protective fabrics in our country s metallurgical industry. It is considered that the standard is more comprehensive and stricter in evaluating the property indicators of fabrics. The implementation of the standard is helpful to protect the personal safety and health of metallurgical operators. [ABSTRACT FROM AUTHOR]

We report a successful fabrication of 0.6Ca0.61Nd0.26TiO3–0.4Nd(Zn0.5Ti0.5)O3 (hereinafter abbreviated as 6CNT–4NCT) microwave ceramics with good sintering activity and desired dielectric properties from EDTA-gel combustion synthesized powders in this paper. The as-synthesized nanopowders have been characterized by X–ray diffraction (XRD), Fourier transformation infrared (FT–IR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) techniques, respectively. The sintering behavior and dielectric performance have been evaluated on the sintered ceramics. The as-obtained product with amorphous structure could be directly crystallized and produced pure 6CNT–4NCT solid solution phase with orthorhombic perovskite structure at a relatively low temperature of 700 °C, without formation of any intermediate phase. TEM images revealed that homogeneous and well dispersed spherical-shaped nanostructure with an average particle size of 23.8 nm was formed at 800 °C. Well-dense 6CNT–4NCT bulk ceramics with 98.8% relative density were obtained at a relatively low sintering temperature of 1225 °C due to high sintering activity of nanopowders. Moreover, the bulk ceramics exhibited a higher quality factor (Q × f) value than those prepared via the conventional solid-state reaction method. Desired microwave dielectric properties were achieved at 1200 °C: dielectric constant εr = 57.2, Q × f = 59,360 GHz, and temperature coefficient of resonant frequency τf = + 1.95 ppm/°C. This study indicates that the EDTA-gel combustion route is a convenient, low-cost, and interesting route to fabricate high-quality microwave ceramics for practical applications. [ABSTRACT FROM AUTHOR]

GB 8965.1--2020 Protective Clothing--Flame Retardant Protective Clothing was analyzed. The new standard and GB 8965.1--2009 Protective Clothing--Flame-retardant Protection--Part 1: Flame-retardant Protective Clothing were compared and analyzed. Changes were listed in terms of flame retardant property, part physical & chemical performance requirements and test methods in new standards. The revision of new standard strengthens rationality and advancement, which meet interests of the country, industry and enterprises. It is considered that standardizing durability evaluation indexes of permanent labels and test methods can ensure permanence of warning effect. [ABSTRACT FROM AUTHOR]