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Construction and demolition waste (C&DW) during new district development shows the characteristics of large quantity, concentrated distribution, and long duration on both supply and demand sides. The construction of the new district has objective conditions to promote the scale development of recycling industries and achieve green development through local digestion, so the recycling indicators for the new district proposed by the government are generally higher than those of other regions. However, many new districts have yet to systematically identify key drivers (KDs) of recycling and form win-win governance mechanisms with multiple government and market subjects, resulting in uncontrolled accumulation or high-cost discard of C&DW. This paper identifies 29 recycling drivers and 8 governing subjects through literature research and a field study of five national new districts in China. Then, a 2-mode social network and two 1-mode social networks are constructed to analyze the complex interactions between drivers and governing subjects, taking Nanjing Jiangbei New District as an example. The results of the study show that most of the drivers need at least 2 governance subjects to promote together, which indicates that it is necessary to build a collaborative governance mechanism of multiple subjects. This study provides a structured framework to analyze the drivers of recycling in new district development and the collaborative governance of multiple subjects, which can provide a basis for promoting efficient recycling of new district development.

Endocrine therapy is often used for advanced prostate cancer. However, with cancer progress, prostate cancer gradually resistant to hormone which lead to serious threatens to life of patients. Herein, a multifunctional synergistic core–shell nanoplatform is reported for improving the therapeutic effect of chemotherapy for advanced or metastatic prostate cancer, and reducing the risk of leakage of chemotherapy drugs. Particularly, Zeolitic imidazolate framework-8 (ZIF-8) is chosen as inner core to load doxorubicin, and the of liposomes which are embedded with IR780 iodide are used as outer shell, and further modified with target ligand that binds to luteinizing hormone releasing hormone receptor. The prepared nanocarrier exhibit satisfactory photothermal effect under near infrared laser irradiation, and the temperature increases to 60.8 °C within 6 min. Meanwhile, the elevated temperature accelerates the degradation of lipid shell, releasing ZIF-8 core to acidic microenvironment of tumor, and resulting in the release of doxorubicin. Moreover, in vivo and in vitro studies have shown the ZIF-D@ALIP core–shell nanoparticles can achieve targeted drug delivery, pH and NIR dual stimuli-responsive drug release, as well as chemotherapy and photothermal therapy synergistically on the tumor site. In addition, the problem of premature leakage and changes in the physicochemical properties of anticancer drugs are avoided under the protection of the outer shell structure. Therefore, the core–shell nanostructure proposes a new lipid membrane coating strategy to promote the effective targeting of prostate cancer cells or tissues and provides some insights in clinical treatment for advanced prostate cancer.

LiCoO2 with a cut-off voltage of 4.6 V (versus Li/Li+) could increase by about 28% of energy density compared with the commercial 4.45 V LiCoO2 cathode. However, severe issues such as oxygen evolution and dramatic phase transition strangle the practical application of 4.6 V LiCoO2. We herein develop a one-step wet chemical coating method at room temperature to stabilize the interface of LiCoO2 under high voltage. Through the treatment of LiCoO2 particles by LiAlH4 solution, the oxygen framework of the surface was reconstructed forming a composite coating layer which is featured a morphology with an inside-out transition structure from order to disorder. Benifited from the Al-containing composite layer, an excellent cycling performance has been obtained on the treated commerical samples, delivering a capacity retention of 70.4% even after 1000 cycles. The key to the improvement of electrochemical performance is to restrain the loss of lattice oxygen which is further elucidated by the results from differential electrochemical mass spectroscopy (DEMS). The interface evolution in different depths was carefully investigated delineating the relationship between the fluorated interface and the enhanced performance. Since the introduction of aluminum hydroxide, it facilitates the capture of F− bringing the interface layer from oxide to more stable fluoride during the cycling. Combining with the first principles calculation results, the aluminum coating surface suppresses the evolution of surfacial oxygen confirmed by oxygen release energy, and the optimized models infer that the fluorinated layer can obviously stabilize the interface structure of LiCoO2. This study provides a direct coating method which confers a notable improvement on cycling stability of LiCoO2 under high voltage and enables the implementation of high energy storage applications.

A LiCoO2 (LCO) cathode with LiBH4 modification (LBH-LCO) was obtained in a facile condition using a fast wet-chemical synthesis method. X-ray photon spectroscopy analysis indicates that B3+ in LiBH...

Prussian blue (PB) and its analogues (PBAs) are considered to be cathode materials for practical applications in sodium-ion batteries due to their open three-dimensional structure and low cost. However, PBAs synthesized by traditional methods generally have poor crystallinity and a high content of [Fe(CN)6] vacancy defects and coordinate water, which not only affect the Na+-storage capacity of PBAs, but also hinder Na+ transportation in the bulk phase and lead to a deterioration in electrochemical performance. Therefore, we propose an unconventional two-phase method to synthesize PBAs. Due to the unique reaction environment of the two-phase method, the reaction time lasts long, which is advantageous to control the synthesis of PBAs to ensure high crystallinity, low defects, and a suitable size. The as-prepared PBA at optimal condition delivers a high initial discharge specific capacity of 152 mA h g−1 at 0.2 C (1 C = 170 mA h g−1), 110 and 105 mA h g−1 even at high current densities of 10 C and 20 C,respectively, as well as a capacity retention of 84% after 200 cycles at 2 C. In particular, superior electrochemical performances also suggested that the two-phase method could be extended to the synthesis of other types of PBAs, such as Mn-PBAs and Co-PBAs, or even more materials with poor crystallinity due to rapid nucleation and growth.

Hollow spherical lithium iron phosphate (LiFePO4) materials display outstanding electrochemical performance in general. Previous reports on hollow spherical LiFePO4 (LFP) mostly focus on electrochemical performance, while the shape evolution process of spherical LFP particles is not clearly investigated. Therefore, in our work a simple solid-state method was applied to synthesize porous hollow spherical LFP with ammonium polyphosphate (APP) as a spheroidizing agent. The as-prepared LiFePO4 forms a “micro–nano” structure, which is in the form of nano-LFP particles interspersed in a micro-hollow-spherical carbon shell, delivering a specific capacity of 163 mA h g−1 at 0.1 C and 123 mA h g−1 at 10 C. More importantly, we clarified the spheroidization process of spherical LFP particles in our work through a series of characterization studies. It is found that APP and the carbon source play critical roles in the shape evolution process at respective temperature regions. Among them, the cohesive behavior of the APP chain results in surface tension and drives the spheroidization process at low temperatures. The carbon source around the LFP particles confines mass transfer and maintains the hollow spherical structure at high temperatures. The exploration of the spheroidization mechanism is instructive for the use of long-chain precursors to synthesize materials with porous-hollow-spherical morphology via a simple process.

Cable-driven parallel robot (CDPR) is a type of high-performance robot that integrates cable-driven kinematic chains and parallel mechanism theory. It inherits the high dynamics and heavy load capacities of the parallel mechanism and significantly improves the workspace, cost and energy efficiency simultaneously. As a result, CDPRs have had irreplaceable roles in industrial and technological fields, such as astronomy, aerospace, logistics, simulators, and rehabilitation. CDPRs follow the cutting-edge trend of rigid-flexible fusion, reflect advanced lightweight design concepts, and have become a frontier topic in robotics research. This paper summarizes the kernel theories and developments of CDPRs, covering configuration design, cable-force distribution, workspace and stiffness, performance evaluation, optimization, and motion control. Kinematic modeling, workspace analysis, and cable-force solution are illustrated. Stiffness and dynamic modeling methods are discussed. To further promote the development, researchers should strengthen the investigation in configuration innovation, rapid calculation of workspace, performance evaluation, stiffness control, and rigid-flexible coupling dynamics. In addition, engineering problems such as cable materials, reliability design, and a unified control framework require attention.

We theoretically propose a broadband transverse unidirectional scattering scheme based on the interaction between a tightly focused azimuthally polarized beam (APB) and a silicon hollow nanostructure. When the nanostructure is located at a specific position in the focal plane of the APB, the transverse scattering fields can be decomposed into contributions from transverse components of the electric dipoles, longitudinal components of magnetic dipoles and magnetic quadrupole components. In order to satisfy the transverse Kerker conditions for these multipoles within a wide infrared spectrum, we design a novel nanostructure with hollow parallelepiped shape. Through numerical simulations and theoretical calculations, this scheme exhibits efficient transverse unidirectional scattering effects in the wavelength range of 1440 nm to 1820 nm (380 nm). In addition, by adjusting the position of the nanostructure on the x-axis, efficient nanoscale displacement sensing with large measuring ranges can be achieved. After analyses, the results prove that our research may have potential applications in the field of high-precision on-chip displacement sensors.

Parallel cables are widely used in cable-driven parallel robots (CDPR) to provide constraints to the end-effector and to realize translational degrees-of-freedom(DOFs). However, when there are structural errors, parallel cables become no longer parallel and will cause orientation errors of the end-effector, which cannot be compensated by kinematic calibration. In this paper, the orientation assurance method is studied considering a 3DOFs translational CDPR. First, the kinematic model and error mapping model of the CDPR are established by using the closed-loop method, considering the pulley radius. Second, the influence of the structural parameters errors on the error of the end-effector is analyzed with the sensitivity index, which establishes a theoretical basis for the simplification of the accuracy synthesis process. Third, the design tolerances of the cable connection points are determined through accuracy synthesis, which is implemented with the genetic algorithm considering the optimal manufacturing cost and the orientation constraints of the end-effector. Finally, to reduce the influence of cable length error, the method of adjusting the initial pose was proposed and studied, which is verified as an effective approach to reduce the orientation error.

Compared with serial robots, parallel robots have the advantages of high stiffness and good dynamics. By replacing the rigid limbs with cables, the cable-driven parallel robot (CDPR) is greatly simplified in structure and lightweight. We designed a high-speed CDPR tensioned by the passive rod and spring, named TBot. The robot can realize the SCARA movement as the classical Delta parallel robot. Comparison analysis of TBot and Delta is carried out to reveal the natures of the CDPRs and rigid parallel robots, identify the key issues, and promote industrial applications. Performance of both robots is analyzed with simulation under a typical Adept Motion trajectory. Results illustrate that TBot has advantages of low cost, low inertia, low energy consumption, and adjustable workspace and has great application potential. Energy consumption of TBot is discussed, and the trajectory planning is studied with the genetic algorithm to further reduce the energy consumption, considering the influence of the passive spring. Finally, on the basis of 30% less energy consumption for the Adept Motion than Delta, extra 14.3% energy is saved through the trajectory planning of TBot.

In this work, we report a new type anode material, MoO 2 combined carbon dots (CDs) with nanoparticle-stacking structure via a facile hydrothermal route. Herein, CDs is introduced as the reductant which in-situ reduces Mo VI to Mo IV . It is further confirmed that the particles of MoO 2 with evenly distributed beset of carbon dots form a nanoparticle-stacking structure. Thanks to this specific structure, the as-made MoO 2 -CDs manifest high performance in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). The capacities maintain 854 and 236 mAh g −1 at 0.50 A g −1 after 300 cycles for LIBs and 600 cycles for SIBs, respectively. Furthermore, we explored the structure-stability relationship by the electrochemical measurement and morphology, found the mechanisms of charge/discharge composed of dominant redox reaction and auxiliary intercalation reaction, and explained the characteristics of a high rate performance through kinetic issues and extrinsic pseudocapacitance contributions. This green synthetic method of anode material could make it possible to obtain high-performance alkali-ion batteries and other energy storage devices.

A closed-loop structure composed of multiple identical branches is a typical feature for parallel mechanisms. The number of joints (including active and passive ones) is much larger than the number of terminal degrees of freedom, and diverse actuation modes (schemes of active joints) are available. Different actuation modes inevitably lead to performance changes. Transformation of actuation modes is a potential way to improve the kinematic performance of parallel mechanisms and deserves further research. In this paper, we propose a novel planar 5R (R denotes revolute joint) parallel mechanism with nine actuation modes. Kinematic performance indices are defined on the basis of matrix orthogonal degree, which possess the advantages of conciseness and clear physical meaning. The performance of the proposed mechanism under different actuation modes is evaluated via the proposed indices. Analysis and simulation results show that the kinematic performance of the parallel mechanism can be significantly improved through reasonable transformations of actuation modes. An optimization method of a variable actuated 5R parallel mechanism is finally established. Optimal dimension and transformation map of optimal actuation modes for the proposed 5R parallel mechanism are obtained. A new approach to improve the kinematic performance of parallel mechanisms by transforming actuation modes is established.

Lithium–sulfur (Li–S) battery with a very high theoretical energy density (∼2500 Wh kg–1) is a very promising alternative to the commercial lithium-ion battery as the next-generation energy storage...

This paper presents a 3-RPaS (R and S denote the revolute and spherical joint, pa denotes the parallelogram) parallel manipulator with two-rotational-degrees-of-freedom (2R1T) and one-translational-degree-of-freedom motion. By introducing parallelograms and an innovative driving module, the 3-RPaS manipulator can change the transmission path of the driving and reaction forces, and achieves 27 actuation modes. The kinematic performance of the manipulator under different actuation modes is analyzed with the indices that are defined based on matrix orthogonal degree. Comparative analysis indicates that the kinematic performance of the manipulator varies significantly in different actuation modes. A reasonable selection of actuation modes can effectively improve the kinematic performance and eliminate singularities. The concept of optimal actuation mode and the implementation approach of actuation mode conversion are discussed and analyzed for kinematics promotion. The kinematic performance of the manipulator is greatly improved with optimal actuation modes, without changing the topology structure and dimensional parameters.

Cable-driven parallel robots (CDPRs) have great prospects for high-speed applications because of their nature of low inertia and good dynamics. Existing high-speed CDPRs mainly adopt redundant cables to keep positive cable tensions. Redundant cables lead to complex and costly structure, and are likely to cause interference. In this study, a non-redundant CDPR for high-speed translational motions is designed with passive springs and parallel cables. First, the configuration of the CDPR is illustrated, and its kinematics and dynamics are studied. Then, the workspace of the CDPR is discussed in detail. The condition of positive cable tensions is proved. The influence of the springs’ layout on the workspace is analyzed. A method for determining the regular cylindrical operation workspace is proposed. Furthermore, the optimal design method for high-speed CDPRs with passive springs is developed. Performance indices for evaluating the force transmission are defined based on the matrix orthogonal degree. The geometric parameters are optimized based on the workspace and force transmission indices. The stiffness coefficient of the spring is determined based on the acceleration and cable tension requirements. Finally, the proposed CDPR and the traditional CDPR with redundant cables are compared through simulation. The results show that the designed CDPR possesses advantages in energy consumption and simple structure compared to CDPR with redundant cables.

The small workspace and complicated singularities severely limit the application of parallel manipulators. The methodology of redundancy is commonly used to eliminate singularity and enhance the kinematic performance of parallel manipulators. However, redundancy results in apparent drawbacks including intensified internal force coupling and complicated dynamic control. A new potential method to improve the kinematics and eliminate singularities, named actuation mode conversion, is investigated in this study. First, a planar 3-RRR parallel manipulator that can realize 27 actuation modes is designed. Based on the matrix orthogonal degree, indices for evaluating the transmission performance are defined, and kinematics of the 3-RRR manipulator under different actuation modes is analyzed. Results indicate that the actuation modes significantly affect the kinematic performance of the parallel manipulator. A reasonable selection of the actuation modes can effectively improve the kinematic performance of the planar 3-RRR parallel manipulator and eliminate type II singularities. Finally, dimensional parameters of the variable-actuated 3-RRR manipulator are optimized via the atlas-based method considering actuation mode conversion, and the optimal conversion map of the actuation modes is obtained.

Integration of various kinds of digital equipment in manufacturing systems is the foundation and premise of cyber-physical systems and intelligent manufacturing. However, interfaces and datatypes of digital equipment from different vendors often differ from each other, which leads to system heterogeneity and information island problems. Heterogeneity becomes an obstacle for information integration. The key to solving this problem is the information model and the communication protocol. To solve the information integration problems among heterogeneous digital equipment, an implementation scheme based on the information model and its mapping to MTConnect is proposed and verified in this paper. First, the architecture and functions of integration of digital equipment are analyzed. Then, a general information model structure of digital equipment and the corresponding modeling rules are established, which can be used to guide the information modeling of various types of equipment. Next, the mapping rules that transform the information model to the MTConnect information model are defined. Based on the information model and model mapping to MTConnect, the digital equipment is able to integrate with other equipment or system via the mapping interface with the aid of the MTConnect protocol. Finally, the implementation of vertical integration based on the information model and its mapping to MTConnect is verified experimentally.

The cable-driven parallel robot (CDPR) uses flexible cables instead of rigid links, and maintains several desirable characteristics, including large workspace, high speed motion, and large payload to weight ratio. Dynamic trajectory planning enables the CDPR to achieve a wide range of motion under small support conditions. In this paper, the stability of dynamic trajectories of cable-suspended parallel robot (CSPR) is investigated. According to the Weak Principle of Equivalence, a stability evaluation index is proposed with the geometric analysis, and is used to carry out the planning of the dynamic trajectories. Taking the planar two degrees of freedom (DoFs) CSPR as object, the simulation is implemented. Results reveal that the cable tension of the dynamic trajectory established with proposed planning method is more uniform, reduces the fluctuation of the cable tension, and improves the stability of the movement. Planning methods of the dynamic trajectory established in this paper provides a new solution for studying the stability of trajectory.

Health evaluation of Computerized Numerical Control (CNC) Machine Tools is an important step to realize condition-based maintenance. In this paper, the evaluation method that merges fuzzy grey clustering and combined weighting is proposed to determine the health status of CNC machine tools. The evaluation process is: Firstly, weights of relevant parameters of the key components of CNC machine tools are calculated and determined by using the entropy weight method and the analytic hierarchy process (AHP) respectively. Then, the two weights are combined by the combination weighting method, and the combination weights with subjective and objective significance are obtained. Then the grey clustering method is used to evaluate the health status of each key component of CNC machine tools. According to the evaluation results, the fuzzy evaluation matrix of machine tool health evaluation is created by the clustering coefficient of each key component of CNC machine tools. Then based on the matrix, the weights of each key component are calculated by entropy weight method and AHP, and the weights of each key component are obtained by the combination weighting method. Finally, the fuzzy comprehensive evaluation method is used to evaluate the health status of CNC machine tools, and the health status is divided into four grades. Finally, the health status of CNC machine tools is determined based on the principle of maximum degree of membership. At the end of the paper, the evaluation experiment is carried out on machining center, which shows the proposed approach is reasonable and usable.

Palladium diselenide (PdSe2), a group-10 transition metal dichalcogenide with great optoelectronic and electrical properties due to unique structure, has gained increasing attention in the scientific community. Herein, we demonstrate an effective strategy to synthesis of ZnO/PdSe2 core–shell heterojunction nanorod arrays (HNAs) through a simple two-step method for the first time. A Pd film was deposited on ZnO NAs by an electron beam evaporation method at first. Then, the selenization process was completed by a chemical vapor deposition (CVD) method. Furthermore, the photoelectric performances of electrodes based on ZnO NAs, PdSe2 film and ZnO/PdSe2 core–shell HNAs were investigated, respectively. The ZnO/PdSe2 core–shell HNA represents better responsitivity with higher photocurrent density (1.3 mA cm−2) comparing to the ZnO NA (0.03 mA cm−2), indicating that the ZnO/PdSe2 samples are more suitable for photoelectric devices. Besides, photoelectric performance of this work is better than most of reported commercial ZnO and ZnO composite nanomaterials.

In general, the functions of most metalenses cannot be adjusted dynamically after being fabricated. Here, we theoretically propose an electrically tunable metalens composed of single-layered and non-structured doped graphene loaded with ribbon-shaped metallic strip arrays with varied widths and gaps. The combination of the different widths and gaps can provide full phase coverage from 0 to 2π, which is necessary for a plane wave to be focused. The metalens exhibits obvious tunability of focal length and focal intensity as we varied the Fermi levels of the doped graphene at 10 THz. The focus is able to be shifted within 90.4 µm (∼3λ), with maximum focusing efficiency up to 61.62%. The tunable metalens can also be expanded to other operation frequencies from mid-infrared to terahertz range by properly designing structural parameters. The metalens consisting of nanostructured metal and non-structured graphene utilizes mature metal nanostructure preparation process and avoids the graphene processing, which consequently facilitates the fabrication and promotes the application.