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In this study, a novel surface amino-functionalized activated carbon (T-AC) was synthesized from coal gasification fine slag (CGFS) and used as an adsorbent for heavy metal ions. T-AC exhibits excellent adsorption capacity for Cd2+ and Pb2+. The adsorption process of Cd2+ and Pb2+ onto T-AC was found to be spontaneous. The dominant adsorption process was chemisorption, primarily involving chelation and covalent bonding. In binary systems, as the initial concentration increases, the independent adsorption effect of Pb2+ and Cd2+ gradually becomes a competitive adsorption effect. Statistical physical models revealed that the adsorption of T-AC for Cd2+ and Pb2+ in single systems followed a multi-molecular adsorption process, whereas in binary systems, it involved a multi-anchorage process. The adsorption capacity was primarily influenced by the number of ions attached to the receptor sites and the density of the adsorbent receptor sites. Moreover, elevating temperature enhanced the thermal movement of heavy metal ions within the pore structure of the adsorbent, reducing their tendency to aggregate at the active sites. This work provides insights into the microscopic-level adsorption process of heavy metal ions by carbon-based materials and contributed to understand of the adsorption behavior. [Display omitted] • Synthesis of amino-modified activated carbon for efficient removal of Cd2+ and Pb2+. • Adsorption mechanism elucidated using classical and statistical physics models. • Multi-molecular adsorption process investigated within a single system. • Binary system explored to understand the multi-anchoring process. • Elucidation of chelation and covalent bonding as the primary adsorption mechanisms. [ABSTRACT FROM AUTHOR]

In this paper, the possibility of detecting topological variations by observing output trajectories from networked linear time-invariant systems is investigated, where the network topology can be general, but the nodes have identical higher-dimensional dynamics. A necessary and sufficient condition on the discernibility of topological variations is derived, in terms of the eigenspaces of the original and the modified network configurations. By taking the specific network structures into consideration, some lower-dimensional conditions are derived, which reveal how the network topologies, sensor locations, node-system dynamics and output, as well as inner interactions altogether affect the discernibility. Furthermore, the output discernibility of topological changes for networked multi-agent systems is revisited, showing that some criterion reported in the literature does not hold. Consequently, a modified necessary and sufficient condition is established. The effectiveness of the results is demonstrated through several examples. [ABSTRACT FROM AUTHOR]

• Exploring the driven force of city sustainable development in enterprises. • Putting forward the economic agenda to achieve cities' low-carbon transformation. • Elucidating how corporate implement city sustainability from stakeholder value. • Pursuing integration of ecological and economic from enterprises perspective. The global consensus on green and city sustainable development is reshaping corporate innovation concepts, strategies, and practice. In the context of Chinese "carbon peak" and "carbon neutrality", encouraging corporate green innovation has become the focus of academic and government attention. As the core element to achieve the goal of city sustainability, corporate green transformation brings technological innovation and the business model change, which impact on firm pollutant discharge, consumer behavior and stakeholder value. These synergies effect provides a green, healthy, and sustainable living environment for city development. Based on the perspective of Stakeholder Influence Theory, this study explores the positive effects of Shareholder Influence on corporate green innovation by empirically testing 17,923 observations of 3205 A-share listed companies in China from 2011 to 2020. The results shows that the decision-making efficiency with Shareholder Power Influence and information advantage with Shareholder Network Influence both promote corporate green innovation. Among them, the power and network of the Top Management Team (TMT) play a moderating role. This study emphasizes the driven force of corporate governance in the context of city sustainable development and puts forward the economic agenda and requirements to achieve cities' low-carbon transformation. [ABSTRACT FROM AUTHOR]

• The study reveals that gender-diverse boards in Shanghai and Shenzhen A-listed firms significantly boost social capital and dynamic abilities. • Greater gender diversity in boards enhances adaptability to business environment shifts, showcasing heightened organizational flexibility. • Findings serve as actionable insights for governance reforms, highlighting the strategic value of gender diversity for improving corporate performance. The world economy is now trending toward a green economy as a kind of sustainable growth. This research uses Chinese A-share listed companies between 2011 and 2021 to analyze the impact of gender diversity on corporate innovation in the boardroom. We find that the presence of women on boards has a favorable impact on both the quantity and quality of green innovations. The role of research and development (R&D) and government funding (government support) as intermediate mechanisms strengthen the connection between women on boards and corporate innovation. Heterogeneous investigations further demonstrate the importance of ESG maturity, gender diversity on corporate boards, and size of business in fostering corporate innovation. The research lends theoretical support to the shift in corporate strategy thinking necessitated by the increased representation of women in senior positions and also gives empirical evidence for the growth of environmentally friendly innovations. [ABSTRACT FROM AUTHOR]

Abstract The leaderless finite-time consensus for second-order Lipschitz nonlinear multi-agent systems with partial-state coupling is investigated, where the communication network is weighted undirected and weighted. A new distributed control algorithm is proposed by designing the appropriate control parameters in the undirected connected communication topology. By using the algebraic graph theory, matrix theory, power integrator technique, and Lyapunov control approach, the leaderless finite-time consensus is achieved for the second-order Lipschitz nonlinear multi-agent systems. The main contribution of this paper is that, the settling time can be estimated by computing the value of the Lyapunov function at the initial point. Finally, the effectiveness of the results is illustrated by some numerical simulations. Highlights • A new novel distributed control algorithm is proposed in the undirected connected communication. • The leaderless finite-time consensus is derived for second-order Lipschitz nonlinearities. • The settling time can be theoretically estimated by computing the value of the Lyapunov function at the initial point. [ABSTRACT FROM AUTHOR]

We study the finite-time consensus control of double-integrator multi-agent systems with external bounded disturbances under the fixed leaderless network communication topology. Based on the relative position and the relative velocity information, a novel finite-time consensus protocol is constructed. By using the Lyapnuov finite-time theory, it is shown that the proposed protocol can coordinate the states of agents to guarantee the finite-time consensus under an undirected connected topology. And then we extend the results onto the strongly connected directed communication topology. Importantly, the finite convergence time of the leaderless systems is explicitly presented. Finally, the effectiveness of the results is illustrated by numerical simulation. [ABSTRACT FROM AUTHOR]

Thermodynamics historically developed out of a desire to quantify the maximal efficiency of early thermodynamic heat engines, especially through the work of French physicist Sadi Carnot. However, the more practical problem about quantifying the limits of power output that can be delivered from the system remained unclear due to the fact that quasistatic process requires infinite operation time, resulting in a vanishing power output. Recent advances in the field of stochastic thermodynamics appear to link the theory and practice, which enables us to mathematically analyze the maximal power and also control design of a thermodynamic heat engine on the microscopic scale. This review aims at summarizing and categorizing previous research on the optimal performance of two kinds of finite-time stochastic thermodynamic engines (a Carnot-like heat engine and the heat engine with a single heat bath) both in the linear and nonlinear response regimes. Thus, this is to be expected, estimated bounds for maximal power output and optimal control can provide physical insights and guidelines for engineering design. We start by reviewing the optimal performance for the Carnot-like engine that alternates between two heat baths of different constant temperatures. Then we discuss the fundamental bounds of the power output for the heat engine with a single periodic heat bath. In each setting, we provide a comprehensive analysis of the maximal power and efficiency both in the linear and nonlinear regimes. Finally, several challenges and future research directions are concluded. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultrasound-assisted anhydrous ethanol method facilitate the separation of different types of carbon from CGFS. • Polymerization soot, amorphous and graphitization carbon were main carbon type in CGFS. • Physicochemical structures of LCD and HCR were compared in detail. A large amount of coal gasification fine slag (CGFS) with substantial carbon is produced in the entrained flow coal gasification process. Understanding the type and activity of the residual carbon in the slag is essential for its efficient use. Coal undergoes a series of complex reaction in a gasifier. The residue carbon contains not only incompletely reacted semi-char, but also soot formed by the condensation of volatile fractions. In this study, the ultrasound-assisted anhydrous ethanol method was used to separate the different types of carbon in the fine slag. Light carbon deposit (LCD) and heavy carbon residue (HCR) were obtained from the top and bottom of the centrifuge tube respectively. The results showed a dry basis yield of 47 % for LCD and 30 % for HCR. LCD particle size is concentrated in the range of 0.2 μm to 5 μm, and the specific surface area is 116 m2/g after de-ashing, in the form of flocs. HCR particle size is concentrated in the range of 20 μm to 100 μm, and the specific surface area is 179 m2/g after de-ashing, composed of irregular particles. The TPO results of the residual carbon in the fine slag were fitted by peak splitting, and three main types of residual carbon were found: polymerization soot, amorphous carbon and graphitization carbon, corresponding to maximum CO 2 release peaks of 596.3 °C, 626.8 °C and 705.6 °C respectively. LCD is composed of polymerization soot. HCR is composed of amorphous carbon and graphitization carbon. Raman characterization reveals that LCD has more active sites than HCR, thus leading to their higher reactivity. This study is an innovative approach to the separation of residual carbon in fine slag. It helps to understanding the formation mechanism of residue carbon in the gasifier. [ABSTRACT FROM AUTHOR]

In this paper, the downlink capacity performance of distributed antenna systems (DAS) with antenna selection are investigated in composite Nakagami channel which take path loss, shadow fading and Nakagami fading into account. According to the performance analysis and using numerical integrations, the probability density function (PDF) and cumulative distribution function (CDF) of the effective output SNR of DAS are derived, respectively. Based on these results, tightly-approximate closed-form expressions of channel capacity and outage probability of DAS in composite Nakagami channel are further derived. These expressions include the ones under composite Rayleigh channel as special cases. Conditioned on the outage probability, a practical iterative algorithm based on Newton's method for finding the outage capacity is proposed. To avoid iterative calculation, another approximate closed-form expression of outage capacity is also derived by utilizing the Gaussian distribution approximation. Simulation results show that the derived expressions have more accuracy than the existing ones, and can match the corresponding simulation well. Thus, the capacity performance of DAS in composite Nakagami channel can be evaluated effectively. [ABSTRACT FROM AUTHOR]

Identifying genes associated with specific diseases plays an important role in the pathological study, diagnosis, and treatment of diseases. In this paper, we propose a new method to identify key genes for any specific disease—the mutual information gene network (MIGN)-structural key gene (SKG). Considering brain tumors as an example, we identified four types of 37 genes that have varying "behaviors" in MIGNs of normal cells and different grades of tumor cells, called SKGs, which are closely related to brain tumors. Using SKGs and K-means clustering algorithm for testing, the test accuracy rate was approximately 94.56%. MIGN-SKG effectively identifies a subset of genes that may be markers of disease progression or therapeutic targets for the disease. The key innovation of MIGN-SKG is that it is unrestricted by differentially expressed genes and it directly identifies key genes from the perspective of changes in genetic relationships during disease progression. It can identify potential key genes for any specific disease as well as other dynamic biological systems. • We proposed a new method to identify key genes for any specific disease. • The proposed method focuses on changes in genetic relationships during disease progression. • We effciently indentified 37 genes that may be brain tumor biomarkers or therapeutic targets. • The proposed method can be applied to identify potential key genes for other dynamic biological systems. [ABSTRACT FROM AUTHOR]

This paper considers the finite-time containment control problem for a class of second-order nonlinear multi-agent systems with external disturbances under the directed topology graph. The considered nonlinear systems are composed of multiple dynamic leaders, and they have only a subset of the followers with their accessing to the leaders. Firstly, by using the one-hop neighbors’ information, a second-order finite-time distributed observer estimator protocol is constructed to achieve accurate estimation of the weighted average of the velocities and positions of the leaders. Furthermore, it is proved that the proposed estimator protocol can guarantee accurate estimation of the weighted average of the velocities and positions of the leaders in the finite-time. Then, we design a new continuous nonlinear control protocol by means of the nonsingular terminal sliding mode. It is shown that by using proposed control protocol, the states of the followers can converge to the convex hull spanned by those of the leaders in the finite-time. In addition, the finite convergence time can be also explicitly estimated. Finally, the effectiveness of the obtained theoretical results is illustrated by the numerical simulation. [ABSTRACT FROM AUTHOR]

We investigate the finite-time cooperative attitude synchronization and tracking control for multiple rigid spacecrafts with a time-varying leader, whose attitude is represented by modified rodriguez parameters. In particular, the studied systems are composed of one dynamic leader with bounded unknown acceleration inputs and some followers with bounded disturbances. A novel nonlinear tracking control protocol is constructed via nonsingular terminal sliding mode scheme. It is shown that the proposed protocol can effectively drive the states of the followers to track the leader within the finite-time. Finally, an example is illustrated to verify the proposed protocol. [ABSTRACT FROM AUTHOR]

This paper concerns with the preassigned-time projective synchronization issue for delayed fully quaternion-valued discontinuous neural networks involving parameter uncertainties through the non-separation method. Above all, based on the existing works, a new preassigned-time stability theorem is established. Subsequently, to realize the control goals, two types of novel and simple chattering-free quaternion controllers are designed, one without the power-law term and the other with a hyperbolic-tangent function. They are different from the existing common power-law controller and exponential controller. Thirdly, under the Filippov discontinuity theories and with the aid of quaternion inequality techniques, some novel succinct sufficient criteria are obtained to ensure the addressed systems to achieve the preassigned-time synchronization by using the preassigned-time stability theory. The preassigned settling time is free from any parameter and any initial value of the system, and can be preset according to the actual task demands. Particularly, unlike the existing results, the proposed control methods can effectively avoid the chattering phenomenon, and the time delay part is removed for simplicity. Additionally, the projection coefficient is generic quaternion-valued instead of real-valued or complex-valued, and some of the previous relevant results are extended. Lastly, numerical simulations are reported to substantiate the effectiveness of the control strategies, the merits of preassigned settling time, and the correctness of the acquired results. [ABSTRACT FROM AUTHOR]