Layered double hydroxide functionalized biomass carbon fiber for highly efficient and recyclable fluoride adsorption

Tao Zhang,Bencheng Zhao,Qiuyun Chen,Xiaoming Peng,Dongya Yang,Fengxian Qiu 한국응용생명화학회 2019 Applied Biological Chemistry (Appl Biol Chem) Vol.62 No.-

The removing of fluoride from water is highly desired from the viewpoint of environmental protection and sustainable development due to the adverse impacts on human and ecosystem. In this study, the hierarchical porous layered double hydroxide (LDH)/biomass carbon fiber (BCF) has been successfully fabricated by the combined sol–gel, carbonization and hydrothermal processes using sustainable bamboo fibers as raw material based on the assembly the LDH nanosheets on BCF surfaces. Structural characterization indicates that the LDH nanosheets were attached to the BCF surface via in situ crystal growth. N2 sorption measurements show that the LDH/BCF has relatively uniform accessible mesochannel size of 3.56 nm, and the surface area is as high as 39.89 m2/g. The resulting LDH/BCF exhibit a noticeable enhanced adsorption capacity for fluoride removal compared to that of Al2O3/ BCF, accompanied by 15.21 mg/g of the adsorption capacity. The presence of the high negative charge anions had negligible influence on fluoride adsorption. Importantly, recovery adsorption capacity for fluoride was obtained for LDH/BCF for 5 consecutive cycles without a significant decrease in its adsorption properties. Therefore, the current research can offer a green approach to fabricate LDH/BCF with hierarchical structures for efficient removing fluoride from water, and the fabricated LDH/BCF will be an excellent candidate for pollution control based on the synergistic effects of BCF and LDH, high adsorption properties with good reusability.

FPoR: Fair proof-of-reputation consensus for blockchain

Tao Zhang,Zhigang Huang 한국통신학회 2023 ICT Express Vol.9 No.1

Current consensus protocols for permissionless blockchain cannot balance security, performance and centralization issues. In the paper, we present a reputation based consensus, FPoR, which combines reputation, committee based consensus, PBFT, reward and penalization mechanisms. FPoR can balance scalability, security and decentralization, and promote fairness, increase participation and strengthen security. Experiment results show that FPoR is with high performance and scalability, which can be used for permissionless blockchain. FPoR can also be extended to permissioned blockchain applications.

Preclinical Study of Cell Therapy for Osteonecrosis of the Femoral Head with Allogenic Peripheral Blood-Derived Mesenchymal Stem Cells

Tao Zhang,Qiang Fu,Ning-Ning Tang,Qian Zhang,Yi Liu,Jia-Chen Peng,Ning Fang,Li-Mei Yu,Jin-Wei Liu 연세대학교의과대학 2016 Yonsei medical journal Vol.57 No.4

Purpose: To explore the value of transplanting peripheral blood-derived mesenchymal stem cells from allogenic rabbits (rPBMSCs)to treat osteonecrosis of the femoral head (ONFH). Materials and Methods: rPBMSCs were separated/cultured from peripheral blood after granulocyte colony-stimulating factor mobilization. Afterwards, mobilized rPBMSCs from a second passage labeled with PKH26 were transplanted into rabbit ONFH models, which were established by liquid nitrogen freezing, to observe the effect of rPBMSCs on ONFH repair. Then, the mRNA expressions of BMP-2 and PPAR-γ in the femoral head were assessed by RT-PCR. Results: After mobilization, the cultured rPBMSCs expressed mesenchymal markers of CD90, CD44, CD29, and CD105, but failed to express CD45, CD14, and CD34. The colony forming efficiency of mobilized rPBMSCs ranged from 2.8 to 10.8 per million peripheralmononuclear cells. After local transplantation, survival of the engrafted cells reached at least 8 weeks. Therein, BMP-2 was up-regulated, while PPAR-γ mRNA was down-regulated. Additionally, bone density and bone trabeculae tended to increase gradually. Conclusion: We confirmed that local transplantation of rPBMSCs benefits ONFH treatment and that the beneficial effects are relatedto the up-regulation of BMP-2 expression and the down-regulation of PPAR-γ expression.

Blockchain and central bank digital currency

Tao Zhang,Zhigang Huang 한국통신학회 2022 ICT Express Vol.8 No.2

With the development of blockchain and digital currencies, central banks all over the world are accelerating the process of CBDC development. However, it is still controversial on adoption of blockchain in CBDC design. In the paper, we analyze both functional and non-functional requirements of CBDC design, and make a literature review on blockchain based CBDC schemes. Analysis findings show that permissioned blockchain are more suitable for CBDC than permissionless blockchain. Besides, there are some challenges in blockchain based CBDC, such as performance, scalability, and cross-chain interoperability. Our analysis is timely and can provide guidelines for blockchain based CBDC design.

Isothermal Crystallization Kinetics of Polyamide 6 with Chain Extender

Tao Zhang,이승준,박규환,강호종 한국고분자학회 2022 Macromolecular Research Vol.30 No.6

The effect of addition of a chain extender (ADR) creating branches on nylon 6 (PA6) by reactive extrusion on the isothermal crystallization behavior is studied. The effect of addition of small amounts of polyketone (PK) capable of forming strong hydrogen bonds with PA6 chains as an additive in reactive extrusion on the isothermal crystallization behavior is also studied. Addition of chain extender to PA6 results in a decrease in the degree of crystallization and the crystallization rate due to the formation of branches, and the increase in the chain extender content or reaction temperature speeds up the reaction forming branches to result in a greater decrease in the degree of crystallization and the crystallization rate. Addition of PK to PA6 results in a decrease in the degree of crystallization and the crystallization rate, and the degree of decrease is dependent on the amount of added PK. Addition of PK along with the chain extender results in a greater decrease in the degree of crystallization and the crystallization rate due to the additional formation of hydrogen bonds between branched PA6 and PK chains.

Full-order and Reduced-order Observer Design for One-sided Lipschitz Nonlinear Fractional Order Systems with Unknown Input

Tao Zhang,Jiaming Tian,Shu-Ping Ma 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.5

This paper studies the problem of designing the unknown input observers (UIOs) for fractional order one-sided Lipchitz nonlinear systems. By introducing a continuous frequency distributed equivalent model and using the matrix generalized inverse approach, sufficient conditions for asymptotic stability of the observer error dynamic systems are presented, which guarantee the existence of the full-order and reduced-order UIOs. All the conditions are obtained in terms of linear matrix inequality (LMI). Furthermore, we show that the obtained results can be applied to a fractional order electrical circuit with the unknown input signal. Two examples are given to demonstrate the applicability of the proposed approach.

Master-Slave Inter-relative Model for Human Assistance Robot

Tao Zhang,Masatoshi Nakamura 한국과학기술원 인간친화 복지 로봇 시스템 연구센터 2003 International Journal of Assistive Robotics and Me Vol.4 No.3

This paper presents a new master-slave inter-relative model (MSIRM) for human assistance robots. This model is composed of inter-relative kinematics and master-slave dynamics. The inter-relative kinematics is defined according to the spatial relation between the human assistance robot and the human body. The master-slave dynamics is defined by assuming the human body as an external load on the human assistance robot. By this modeling method, a 5-DOF meal assistance robot was modeled. With the simulation and the experimental work for the meal assistance robot, the appropriateness and effectiveness of this model were verified. With this model, the complex kinematics and dynamics of the human assistance robot can be made simple. Moreover, the features of the human assistance robot can be expressed according to the relation between the human assistance robot and the human body. And, the influence of the human body upon the human assistance robot can be analyzed. With this model, it is also possible that the controller of the human assistance robot be properly constructed.

High performance KNN-based single crystal thick film for ultrasound application

Tao Zhang,Jun Ou-Yang,Xiaofei Yang,Wei Wei,Benpeng Zhu 대한금속·재료학회 2019 ELECTRONIC MATERIALS LETTERS Vol.15 No.1

Using a novel lapping technology, the achievement of approximately 28 μm (K 0.45 Na 0.55 ) 0.96 Li 0.04 NbO 3 (abbreviated asKNLN) single crystal thick fi lm with <001> orientation has been realized. This kind of thick fi lm exhibited excellent electricalperformance: a superior piezoelectric constant (~ 490 pm/V) and an outstanding electromechanical coupling coeffi cient(k t ~ 0.55). Based on the obtained KNLN single crystal thick fi lm, a tiny side-looking 82 MHz ultrasound transducer witha bandwidth of 57.3% at − 6 dB has been successfully fabricated. Most importantly, 80 MHz intravascular ultrasound andphotoacoustic images of the healthy rabbit aorta have been presented. All these promising results indicate that KNN-basedsingle crystal thick fi lm is a good environmental protection candidate for high frequency (~ 80 MHz) ultrasound applications.

A Hybrid Path Planning Method for Partly Unknown Environment

Tao Zhang,Yi Zhu,Jingyan Song 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

For efficiently solving path planning problem in partly unknown environment and making full use of the prior known knowledge of the environment and the sensor based information, a hybrid method consisting of both global and local path planning is proposed in this paper. In this hybrid method, a new approach for generating the sequence ofsub-goal is proposed. Most importantly, comparing with some related works, the proposed method pays more attentionto the capability of local planning layer instead of global planning layer, which results in more reliable ability to escapefrom trap in partly known environment without expensive computation. The simulation results verified the effectiveness of the proposed method.

Biomass Stabilization: Phosphorus Fixation and Utilization

Tao Zhang 대한환경공학회 2019 대한환경공학회 학술발표논문집 Vol.2019 No.-