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The purpose of this paper is to reveal the mechanism of nitrite (NO_2⁻) for the surface passivation of carbon steels in acidic environments through investigating the influences of 0.01 mol/L NaNO₂ addition on the corrosion and passivation behaviors of Q235 carbon steel in acidic phosphate buffer (APB) solutions (pH 2 to 6).

The electrochemical techniques including open circle potential evolution, potentiodynamic polarization, electrochemical impedance spectroscopy and cyclic voltammetry were applied.

In APB solutions without NO_2⁻, the Q235 steel presented the electrochemical behaviors of activation (A), activation-passivation-transpassivation and self-passivation-transpassivation at pH 2 to 4, pH 5 and pH 6, respectively; the corrosion rate decreased with the up of pH value, and the surface passivation occurred in the pH 5 and pH 6 solutions only: the anodic passivation at pH 5 and the spontaneous passivation at pH 6.

In APB solutions without NO_2⁻, the corrosion rate decreased with the up of pH value, and the surface passivation occurred in the pH 5 and pH 6 solutions only: the anodic passivation at pH 5 and the spontaneous passivation at pH 6. With the addition of 0.01 mol/L NaNO₂, into APB solutions, the variation of corrosion rate showed the same rule, but the surface passivation occurred over the whole acidic pH range, including the anodic passivation at pH 2 to 4 and the spontaneous passivation at pH 5 to 6.

The sudden outbreak of COVID-19 has become a major public health emergency of global concern. Studying the Internet public opinion dissemination mechanism of public health emergencies is of great significance for creating a legalized network environment, and it is also helpful for managers to make scientific decisions when encountering Internet public opinion crisis.

Based on the analysis of the process of spreading the Internet public opinion in major epidemics, a dynamic model of the Internet public opinion spread system was constructed to study the interactive relationship among the public opinion events, network media, netizens and government and the spread of epidemic public opinion. The Shuanghuanglian event in COVID-19 in China was taken as a typical example to make simulation analysis.

Research results show three points: (1) the government credibility plays a decisive role in the spread of Internet public opinion; (2) it is the best time to intervene when Internet public opinion occurred at first time; (3) the management and control of social media are the key to public opinion governance. Besides, specific countermeasures are proposed to assist control of Internet public opinion dissemination.

The epidemic Internet public opinion risk evolution system is a complex nonlinear social system. The system dynamics model is used to carry out research to facilitate the analysis of the Internet public opinion propagation mechanism and explore the interrelationship of various factors.

This paper aims to provide a precise tracking control scheme for multi-input multi-output “MIMO” nonlinear systems with unknown input time-delay in industrial process.

The predictive control scheme based on multi-dimensional Taylor network (MTN) model is proposed. First, for the unknown input time-delay, the cross-correlation function is used to identify the input time-delay through just the input and output data. And then, the scheme of predictive control is designed based on the MTN model. It goes as follows: a recursive d-step-ahead MTN predictive model is developed to compensate the influence of time-delay, and the extended Kalman filter (EKF) algorithm is applied for its learning; the multistep predictive objective function is designed, and the optimal controlled output is determined by iterative refinement; and the convergence of MTN predictive model and the stability of closed-loop system are proved.

Simulation results show that the proposed scheme is of desirable generality and capable of performing the tracking control for MIMO nonlinear systems with unknown input time-delay in industrial process effectively, such as the continuous stirred tank reactor (CSTR) process, which provides a considerably improved performance and effectiveness. The proposed scheme promises strong robustness, low complexity and easy implementation.

For the limitations of proposed scheme, the time-invariant time-delay is only considered in time-delay identification and control schemes. And the CSTR process is only introduced to prove that the proposed scheme can adapt to practical industrial scenario.

The originality of the paper is that the proposed MTN control scheme has good tracking performance, which solves the influence of time-delay, coupling and nonlinearity and the real-time performance for MIMO nonlinear systems with unknown input time-delay.

The aim of this work was to propose a method to prepare composite phosphate conversion coating (CPCC), including ternary phosphate conversion coating (TPCC) and binary phosphate conversion coatings (BPCC), with one-step chemical conversion and to reveal and compare the corrosion resistance between TPCC and BPCC.

In this work, a calcium–manganese–zinc (Ca–Mn–Zn) TPCC was prepared on the surface of magnesium alloy (MA) AZ91D with one-step chemical conversion method; for Ca-Mn-Zn@TPCC, its microstructure was characterized with scanning electron microscope observation and scanning tunneling microscope detection, and its composition was characterized with energy dispersion spectroscopy and X-ray photoelectron spectroscopy analyses. Particularly, the corrosion resistance of Ca-Mn-Zn@TPCC and its comparison with Ca–Mn, Ca–Zn and Mn–Zn BPCCs were clarified with electrochemical and immersion measurements.

Ca-Mn-Zn@TPCC, which was composed of Ca, Mn, Zn, P and O, exhibited a mud-shaped with cracks microstructure, and the average crack width, terrain fluctuation and coating thickness were 0.61 µm, 23.78 nm and 2.47 µm, respectively. Ca-Mn-Zn@TPCC provided good corrosion resistance to MA AZ91D; in NaCl solution, the total degradation of Ca-Mn-Zn@TPCC consumed eight days; corrosion products with poor adhesion peeled out from Ca-Mn-Zn@TPCC-coated MA AZ91D spontaneously. Besides, the corrosion resistance of Ca-Mn-Zn@TPCC was better than that of Ca-Mn@BPCC, Ca-Zn@BPCC or Mn-Zn@BPCC.

The successful preparation of Ca-Mn-Zn@TPCC on MA AZ91D surface confirmed the proposed method to prepare CPCC with one-step chemical conversion was feasible; at the same time, it was further confirmed that for phosphate conversion coating, ternary coating had better corrosion resistance than binary coating did.

This paper considers supply chain management organizations with the aid of 'chaotic systems theory' developed originally in physics and mathematics. Since innovations in supply chain management are vital for organizational survival 'complex systems theory' may assist in fine-tuning managerial philosophies that provide stability in supply chain management because it is on the boundary of chaos that the greatest innovational creativity occurs. Neither 'management by rigid objectives' (MBO) nor 'management by instruction' (MBI) will be suitable for the information society of the twenty-first century because chaotic social systems will no longer be effectively managed. However, the capacity for self-organization will be derived essentially from how supply chain management members accept a shared set of values or principles for action-'management by values' (MBV). Complex systems theory deals with systems that show complex structures in time or space, often hiding simple deterministic rules. This theory holds that once these rules are found, it is possible to make effective predictions and even to control the apparent complexity. The state of chaos that self-organizes is attributable to the appearance of the 'strange attractor' and provides the ideal basis for creativity and innovation in the twenty-first century. In the self-organized state of chaos, social members are not confined to narrow roles and gradually develop their capacity for differentiation and relationships, growing progressively towards their maximum potential contribution to the efficiency of the organization. In this meaning, values act as organizers of 'attractors' of disorder, which, in the theory of chaos, are systems represented by usually regular geometric configurations that predict the long-term behavior of complex systems. In supply chain management organizations (as in all kinds of social systems) the initial principles end up as the final principles in the long term. An attractor is a model representation of the behavioral results of the system. The attractor is not a force of attraction or a goal-oriented presence in the system; it simply depicts where the system is heading based on its rules of motion. In supply chain management organizations that cultivate or shares values of autonomy, responsibility, independence, innovation, creativity, and proactivity, the risk of short-term chaos is mitigated by external complexities that organizations are currently confronting. The strategy is to alter the supply chain management's surroundings so that they can benefit from management by values (MBV).

Negative rumors damage the destination’s image and tourist experience. This study aims to compare how rumor correction sources (government vs business vs tourist) affect user online citizenship behavior (UOCB).

Based on the stimuli-organism-response framework, a hypothetical model was established from rumor correction to UOCB. Three scenario experiments (more than 1,000 valid samples) were designed. Study 1 illustrated the effects of different rumor corrections, Study 2 was designed to verify the mediating effects of sympathy and perceived information authenticity (PIA) and the robustness of results was demonstrated in Study 3.

Government correction elicited the highest sympathy and PIA. Business correction was less than tourist correction in arousing sympathy but better than tourist correction in enhancing PIA. Sympathy and PIA had a mediating effect on the relationship between rumor correction and UOCB.

This study helps to identify the different advantages of rumor correctors and provides insights to prevent the deterioration of negative tourism rumors or even reverse these crises.

This study innovates research perspective of negative tourism rumor governance, expands the understanding of the effect and process of rumor correction and enriches the research content of tourism crisis communication.

负面谣言破坏目的地形象和游客体验。本研究比较谣言纠正来源（政府、企业、游客）对用户在线公民行为的影响。

基于刺激-有机体-反应框架, 搭建谣言纠正到用户在线公民行为的假设模型, 并设计3个情境实验（超过1000个有效样本）。实验1验证不同谣言纠正来源的纠正效果, 实验2证明同情和感知信息真实性的中介作用, 实验3测试实验结果的稳健性。

政府纠正引发最高的同情和感知信息真实性。企业纠正在唤起同情时不足于游客纠正, 但在增强感知信息真实性时优于旅游纠正。同情和感知信息真实性在谣言纠正与用户在线公民行为之间发挥中介作用。

有助于识别各个谣言纠正主体的不同优势, 为防止旅游负面谣言恶化甚至转危为安提供见解。

为旅游负面谣言治理提供新的研究视角, 拓展了对谣言纠正效果和过程的认识, 丰富了旅游危机沟通的研究内容。

Los rumores negativos dañan la imagen del destino y la experiencia del turista. Este estudio compara cómo afectan las fuentes de corrección de rumores (gobierno vs empresas vs turista) en el comportamiento cívico online de los usuarios (CCOU).

Sobre la base del marco estímulo-organismo-respuesta, se estableció un modelo hipotético desde la corrección de rumores hasta el CCOU. Se diseñaron tres escenarios experimentales (más de 1.000 muestras válidas). El Estudio 1 ilustró los efectos de las diferentes correcciones de rumores, el Estudio 2 se diseñó para verificar los efectos mediadores de la simpatía y la autenticidad percibida de la información (API), y la solidez de los resultados se demostró en el Estudio 3.

La corrección del gobierno obtuvo la mayor simpatía y API. La corrección de la empresa despertó menos simpatía que la corrección del turista, pero fue mejor para generar API. La simpatía y la API tuvieron un efecto mediador en la relación entre la corrección del rumor y el CCOU.

Ayuda a identificar las diferentes ventajas de los correctores de rumores y proporciona información para prevenir el deterioro de los rumores turísticos negativos o incluso revertir estas crisis.

Proporciona una nueva perspectiva de investigación de la gobernanza del rumor turístico negativo, amplía la comprensión del efecto y el proceso de corrección de rumores y enriquece el contenido de la investigación de la comunicación de crisis turísticas.

This study aims to investigate the impact of earnings predictability and truthfulness on nonprofessional investors’ investment willingness.

Earnings predictability is captured by quarterly earnings autocorrelation, and earnings truthfulness is indicated by real earnings management (REM). The average of investment attractiveness and willingness measures investment willingness. The authors use experiments to isolate the impact of quarterly earnings autocorrelation and REM on investors’ investment behaviors.

From the 2 × 2 design, the authors observe that investors weight more on earnings predictability than earnings truthfulness.

The generalization of the findings may be constrained for the following reasons. First, the authors use only one proxy, REM, to measure earnings truthfulness. In addition, the authors provide the participants, Amazon Mechanical Turk, with earnings predictability. Results may no longer hold if each participant has different understanding and analysis of earnings predictability.

In periods of unprecedented and severe financial uncertainty (i.e. the COVID-19 pandemic), investors rely more on earnings predictability than on earnings truthfulness. The study assists managers to strategically emphasize the predictability of earnings to attract investors, especially when firms face financial challenges or uncertainty.

This study contributes to understanding investor behavior and the critical role of earnings predictability and truthfulness in shaping investment decisions.

This paper contributes to the literature of earnings properties in financial reporting, particularly by shedding light on the nuanced interplay between earnings predictability and earnings truthfulness. The research also demonstrates that elevated earnings autocorrelation indirectly stimulates investment willingness by enhancing the investors’ perception of earnings persistence of targeted firms.

This paper aims to clarify the impact of information asymmetry on users' payment rates and examine the role of perceived uncertainty (PU) and acceptable price (AP) in the relationship between information asymmetry and users' payment rates.

To test the influences of information asymmetry on users' payment rates, this paper collects 18,489 transaction data from the Chinese knowledge payment platform Zhihu with a Python crawler. This paper constructs a mediation model to define the relationship between information asymmetry and users' payment rates by introducing PU and AP as the mediators.

Information asymmetry negatively affects users' payment rates. In addition, PU and AP mediate the information asymmetry in users' payment rates bond.

This study only explores the mediators of the information asymmetry users’ payment rates bond, ignoring the effect of potential moderators, which would be an important direction for future research.

The findings of this paper suggest that information communication is essential in knowledge market transactions. Knowledge providers, as well as knowledge platforms, should enhance information exchange with consumers in order to increase product sales.

This paper provides a new perspective for understanding how information asymmetry affects users' payment rates and helps to guide suppliers to improve product quality. The research framework of this paper is universal to a certain extent.

This paper is one of the first to propose using PU and AP to construct a mediation model to study the information asymmetry between users' payment rates relationship. It provides a new perspective for understanding the channel of information asymmetry in customer behavior.

The paper aims to discuss the amended provisions relating to protection of minority shareholders (PMS) in the newly amended Chinese Company Law and evaluate whether it adequately protects the interests of minority shareholders.

In total, 26 cases will be examined by discussing the characteristics of the relevant parties involved, specifically plaintiffs, defendants, their lawyers, judges and also the grounds of complaint. A comparison will be made between the cases decided by following the first Company Law (1994) and the cases decided in accordance with the newly amended Company Law (2006).

The findings indicate that the amended Company Law has removed certain drawbacks in PMS present in the first Company Law (1994) but the New Company Law can protect interests of minority shareholders only to a certain extent. Further amendments are still needed.

This is one of the first studies to actually examine the implementation of PMS‐related provisions in the newly amended Company Law.

The main cause of aseptic inflammation after an in vivo implantation is that Poly(L-lactide) (PLLA) and Poly(D-lactide) have a slower degradation and absorption rate, while Poly(D, L-lactide) (PDLLA) has a much faster degradation rate than PLLA because of its amorphous structure. Also, the hydrolyzate of Hydroxyapatite (HA) is alkaline, which can neutralize local tissue peracid caused by hydrolysis of Polylactic acid.

In this study, the selective laser sintering (SLS) technique was chosen to prepare bone scaffolds using nano-HA/PDLLA composite microspheres, which were prepared by the solid-in-oil-in-water (S/O/W) method. First, the SLS parameters range of bulk was determined by the result of a single-layer experiment and the optimized parameters were then obtained by the orthogonal experiment. The tensile property, hydrophobicity, biocompatibility, biological toxicity and in vitro degradation of the samples with optimized SLS parameters were characterized.

As a result, the samples showed a lower tensile strength because of the many holes in their interior, which was conducive to better cell adhesion and nutrient transport. In addition, the samples retained their inherent properties after SLS and the hydrophobicity was improved after adding nano-HA because of the OH group. Furthermore, the samples showed good biocompatibility with the large number of cells adhering to the material through pseudopods and there was no significant difference between the pure PDLLA and 10% HA/PDLLA in terms of biological toxicity. Finally, the degradation rate of the composites could be tailored by the amount of nano-HA.

This study combined the S/O/W and SLS technique and provides a theoretical future basis for the preparation of drug-loaded microsphere scaffolds through SLS using HA/PDLLA composites.