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In recent years, the negative consequences of climate change have gradually spread to the real economy sector, which affects enterprise output, increases enterprise costs, and thus inhibits the sustainable development of enterprises. Still, it is not clear whether corporate resource misallocation will reinforce the effect. Therefore, using the data of A-share listed companies in 2011–2021, this paper investigates the impact of climate change on corporate environmental, social, and governance (ESG) performance. According to empirical results, climate change significantly inhibits corporate ESG performance. It also found that continuously eliminating internal and external resource misallocation helps alleviate the adverse effects of climate change on ESG performance. Furthermore, compared with enterprises in non-resource-based cities, climate change will significantly improve corporate ESG performance in resource-based cities, indicating that the adaptive behavior caused by climate change has partially broken the resource curse phenomenon. Additionally, mature and large-scale enterprises mitigate the negative effects better, and external pressure from the public environmental and analysts' attention can motivate companies to improve their ESG performance. The research enriches the research on the impact of climate change on corporate ESG performance and provides a reference basis for enterprises to cope with climate risks. [ABSTRACT FROM AUTHOR]

Exploring dynamic response-based damage identification under wave excitation is important for establishing a health monitoring system. In our previous study, we analyzed the characteristics of the rigid-body dynamic response and successfully employed them to identify the damage location of a pile foundation. Nevertheless, some recent researches show that the local flexural response resulting from wave impact has stronger energy performance. Therefore, this paper constructed a new damage identification method by making full use of energy and phase slope of the local flexural response. Firstly, a novel frequency domain clustering algorithm based on the Sub-peaks Suppression of Power Spectral Density Method (SSPSDM) was proposed to address the challenge of mode mixing in signal decomposition. Subsequently, the new composite energy factors were developed by combining both energy and phase of the local flexural response to enhance the sensitivity and robustness of damage identification. Finally, the method was validated using the acceleration signals from a laboratorial high-piled wharf model. The results show that the method can effectively extract the damage feature sub-signal and the composite energy factor based on phase slope enables better identification of the damage location and degree, enhancing the accuracy of the damage assessment process. • A frequency domain clustering method was proposed to extract different responses. • The Sub-peaks Suppression of Power Spectral Density Method was proposed. • The composite energy factors with better identification effect were proposed. • The effects of decomposition algorithms for damage identification were compared. [ABSTRACT FROM AUTHOR]

Graphite-based metal transition-layer substrates hold great potential for preparing large-area diamond films and achieving crack-free release. In this study, a five-inch crack-free free-standing diamond film was prepared on a graphite substrate with a sacrificial Mo/Ti double-layer transition layer using direct-current arc plasma jet chemical vapor deposition (DC jet CVD). The interfacial bonding and diffusion behavior between the diamond and the transition layers were investigated. The effect of abundant metal particles and elemental diffusion between layers on film adhesion and stress release are discussed and analyzed. The surface of Ti layer prepared by the multi-arc ion-plating contains numerous metal particles that provide a template for the fine-crystalline Mo layer. Metal particles are encapsulated and embedded in the diamond and act as anchors that ensure the stability of the substrate–diamond bond during high-temperature deposition. After deposition, those metal particles act as weak points and play crucial stress-release roles. Mutual elemental diffusion occurs between the Ti, Mo, and diamond layers. Ti penetrates the Mo layer to form a continuous 140-nm-thick thin layer during the initial deposition period, facilitating diamond nucleation. Carbon from the plasma and diamond diffuses into the metal transition layer. Thermal stress generated between the diamond and the graphite substrate is released by destroying the metal transition layer with high thermal expansion coefficient and low elastic modulus during cooling from the deposition temperature. Cracks rapidly propagate along the interface between destroyable transition layers and graphite substrate, which results in the liftoff of a fully crack-free diamond film. [Display omitted] [ABSTRACT FROM AUTHOR]

• A self-consistent multi-physics coupling model including microwave electromagnetic field, plasma field and fluid heat transfer field is established. • CH 4 -H 2 plasma characteristics from 18 to 100 W∙cm−3. • Kinetics of CH 4 -H 2 plasma chemical reaction at high average power density. • High-rate growth of high-quality Φ 60 mm diamond films at high average power density of 100 W∙cm−3. Investigating the mechanism behind the high-efficiency deposition of high-quality diamond has always been a prominent topic in related research. This paper investigates the CH 4 -H 2 plasma characteristics and related chemical reaction kinetics in the average power density range of 18–100 W·cm−3, which is a typical range for large-area diamond film deposition. The number densities of H, CH 3 and C 2 H 2 increase linearly with the average power density. C 2 H 2 is the main hydrocarbon in the discharge, and CH 3 is the main single-carbon hydrocarbon. The number density and radial uniformity of CH 3 and C 2 H 2 increase with the average power density, which is necessary for the high rate and uniform deposition of diamond films. The plasma's optical emission spectra indicate an acceleration in the C 2 production rate at high power density. The diamond film deposition experiment demonstrates the efficacy of high average power density in achieving high-quality diamond deposition at a high growth rate. [ABSTRACT FROM AUTHOR]

A piece of diamond film (Ø 125 mm) was polished based on prefabricated stress. The diamond film was glued to a metal workpiece at high temperatures. The difference in the thermal expansion coefficients between the diamond film and the workpiece was exploited to prefabricate stress in the middle of the two materials. This prefabricated stress had a compressive effect on the diamond film, offset the stress generated in the grinding and polishing process, and prevented the diamond film from cracking. The feasibility of the prestressing method was verified by a combination of experiments and finite element simulations. The prestressing method was used to bond the diamond film to a 10 mm-thick brass fixture at 20, 50, 70, and 90 °C. It was found that when the temperature of the bonded diamond film reached 90 °C, the increase in the prefabricated stress was −410.71 MPa. The finite element simulation results were found to be consistent with the experimental data. The diamond film was cooled down to room temperature after bonding at high temperatures to simulate the prefabricated stress generation process. The diamond film with the prefabricated stress was again heated to the bonding temperature to simulate the stress change caused by the frictional heat generated during the polishing process. The stress of the bonded sample increased when it was cooled down to room temperature. The stress on the diamond surface became smaller during the polishing process, and the stress almost disappeared with the rise in bonding temperature, verifying the viability of the prestressing method. [Display omitted] • Prestressing method to polish a large-sized diamond film was proposed. • Diamond film was bonded to the metal fixture at high temperature and cooled. • The prefabricate stress was measured and simulated. • A Ø125 mm diamond film was successfully polished using this idea. [ABSTRACT FROM AUTHOR]

Lipid monitoring plays a crucial role in biomedical research, particularly in the areas of cardiovascular health, metabolic disorders and nutrition. However, direct and highly sensitive detection of lipids poses significant challenges due to the interference of high SERS background noise in lipid samples. In this study, we present a SERS platform for the quantitative analysis of lipids. By harnessing the Surface Plasmon Resonance (SPR) effect of nanostructured grooves and leveraging deuterium oxide, a remarkable enhancement of in-situ Raman signals originating from cholesterol is achieved. This approach yielded an impressive average enhancement factor of 7.3 × 105 and a detection limit of 1.9 × 10−4 mg/mL, highlighting the exceptional sensitivity and precision of our method. We have obtained high quality, in-situ SERS signals for six distinct lipid molecules. Rapid identification of lipid samples in mixed systems has been achieved through the combination of characteristic peak analysis and PCA-LDA, including the detection of SERS signals from lipids in milk. Notably, univariate monitoring of in-situ cholesterol in human serum was successfully achieved for the first time using deuterium water as an internal standard. In addition, silver substrate demonstrated outstanding reproducibility, maintaining consistent SERS activity even after more than 10 repetitions. Therefore, this platform offers the distinct advantages of high sensitivity, specificity and cost-effectiveness for lipid detection. These findings enable dietary management and blood lipid monitoring, and therefore hold crucial implications for the early prevention of lipid-related disorders and diseases. [Display omitted] • A SERS platform for highly sensitive in situ detection of lipids was designed. • SERS signal of cholesterol in situ was significantly enhanced by the SPR effect and D 2 O of nanostructured grooves. • Rapid identification of six different lipid molecules was realized. • For the first time, a univariate monitoring of human serum in situ cholesterol was achieved. [ABSTRACT FROM AUTHOR]

Deposition of a consistent diamond coating on intricate surfaces has historically posed a difficulty. This article presents the advancement in research on depositing a uniform diamond coating on three-dimensional (3D) silicon spheres, utilizing a faraday cage within a microwave plasma chemical vapor deposition (MPCVD) reactor. A self-consistent three-dimensional multi-physics field model has been established for simulating the microwave electric field and plasma inside a reactor with or without a faraday cage. Results indicate the cage effectively reduces the discharge at the top of the silicon sphere and improves uniformity of the distribution of the microwave electric field and plasma electron density on the sphere's surface. MPCVD trials have demonstrated that a powerful discharge takes place at the apex of the silicon sphere resulting in an excessive thermal gradient if the cage is not added. The apex of the silicon sphere is covered with a blend of diamond and graphite phases. Due to the excessive internal stress of the coating, approximately 50 % of the samples experience coating detachment. After the addition of the cage, the strong discharge is transferred to the top of the cage, effectively suppressing the microwave electric field and plasma inside the cage. Improved quality, reduced internal stress, and enhanced uniformity of the polycrystalline diamond coating are achievable on the silicon spheres within the cage. Moreover, this technique offers a novel approach to coat diamond on complex 3D geometries. [Display omitted] • Three-dimensional multi-physics modeling verifies that faraday cage suppresses microwave electric field and plasma. • The Faraday cage improves the uniformity of the distribution of microwave electric fields and plasma in the internal space. • Uniform, high crystal quality, low stress diamond coating. [ABSTRACT FROM AUTHOR]

The direct-current arc plasma jet method is advantageous for the rapid deposition of large-area self-supporting diamond films. However, dark defects tend to be generated during the growth process, significantly affecting the performance of the diamond. In this study, we use the direct-current arc plasma jet method to prepare transparent and translucent samples. Subsequently, we compare their optical, thermal, and mechanical properties and analyze the differences in their performances via microstructure and defect analyses. The results indicate that the transparent diamond samples exhibit excellent optical and thermal properties, with a transmittance of 68.4 % at a wavelength of 10.6 μm and a thermal conductivity similar to that of type-IIa single crystal diamond (i.e. 2002 W/(m·K)). Meanwhile, the translucent diamond exhibits outstanding mechanical properties, with a fracture strength of 984 MPa. Characterization results based on electron backscatter diffraction and X-ray computed tomography suggest that a preferred orientation along the (220) planes is conducive to the densification growth of the samples, thereby enhancing their optical and thermal properties. However, the generation of numerous twins results in interlocking between grains, which improves sample's mechanical properties but introduces porosity and impurities, thus deteriorating its optical and thermal performance. [Display omitted] • Optical and thermal diamond films were deposited by DC-arc plasma jet CVD with growth rates >6 μm/h. • Strong (220) texture and numerous twins can improve optical transmittance and fracture strength, respectively. • X-ray CT was used to reveal defects distribution and content within diamond samples. [ABSTRACT FROM AUTHOR]

Diamond is a highly attractive material for many applications in material science, engineering, chemistry, and biology because of its favorable properties. The preparation of large-area freestanding diamond plate can greatly reduce the production cost of diamond and promote the industrialization of diamond. In this study, the dual-magnetic field mode was introduced to optimize the magnetic field distribution in direct current arc plasma jet chemical vapor deposition (DC Jet CVD) system, and the arc plasma was effectively controlled under the coupling of electric field and magnetic field. The uniformity of the plasma distribution above the substrate surface is significantly improved, resulting in long-term stable and uniform growth of the 8-inch freestanding diamond plate. The influence of dual-magnetic field mode on magnetic field generation, arc feature, and reactive group distribution was studied. 8-inch freestanding diamond plates with an average thickness of 2.8 mm were prepared by dual-magnetic controlled DC Jet CVD. The results showed that the 8-inch diamond plate preferred a high (220) orientation, and the deviation of thickness of which was around 10 % of the averaged values. Raman spectroscopy of diamond revealed a 6.6 cm−1 of full width at half maximum (FWHM) and calculated 1.20 GPa compressive stress in the 8-inch diamond plate. By means of mechanical and thermal property measurements, the large area diamond plate shows a robust structure with the average values of three-point bending fracture strength of 987.2 MPa, and extremely high thermal conductivity of 1797.8 W/(m·k) as well. The deviation of three-point bending fracture strength and the thermal conductivity over the 8-inch diamond plate was around 7.9 % and 12.6 % of the respective averaged values. [Display omitted] • A uniform and robust 8-inch diamond plate was prepared using a dual-field DC arc CVD system. • The average three-point bending fracture strength of the 8-inch diamond plate was 987.23 MPa, and the average thermal conductivity was 1797.80 W/(m•K). • The effect of dual magnetic field mode on the distribution of arc morphology and arc plasma groups was analyzed using a high-speed camera and filter. [ABSTRACT FROM AUTHOR]