Investigation on the fluorine recovery mechanism by air stripping for synthetic and industrial wet process phosphoric acid

Binbin He,Yun Zu,Yunxiang Nie,Yi Mei 한국탄소학회 2023 Carbon Letters Vol.33 No.7

Fluorine (F) recovery from wet process phosphoric acid (WPA) is essential for sustainable resource utilization and environmental protection. This work systematically investigates the F recovery mechanism by air stripping from three simulated systems: H3PO4- H2SiF6-H2O, H3PO4- HF-H2O, H3PO4- H2SiF6-HF-Al3+-H2O, and from two industrial systems: WPA and WPA-Al3+ under different stripping temperatures (60–110 ℃) and stripping times (0–120 min). The influence on the existence form of F, the content of Al3+ cations and the addition of active silica on the F removal rate in the phosphoric acid solution is studied by analyzing the changes in the contents of F, P and Si. The results indicate that the F in the form of H2SiF6 is more easily released from the phosphoric acid solution than that in the form of HF. While, the release of F is inhibited in the presence of the Al3+ in the solution due to the formation of Al-F complexes that are characterized by 19F NMR, 31Si NMR and FTIR techniques. Interestingly, the addition of active silica can promote the conversion of HF to H2SiF6 in the solution and significantly improve the release rate of F. The researching results can provide an important guidance for industrial practice of WPA.

Reliability of mortar filling layer void length in in-service ballastless track-bridge system of HSR

Binbin He,Sheng Wen,Yulin Feng,Lizhong Jiang,Wangbao Zhou 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.47 No.1

To study the evaluation standard and control limit of mortar filling layer void length, in this paper, the train submodel was developed by MATLAB and the track-bridge sub-model considering the mortar filling layer void was established by ANSYS. The two sub-models were assembled into a train-track-bridge coupling dynamic model through the wheel-rail contact relationship, and the validity was corroborated by the coupling dynamic model with the literature model. Considering the randomness of fastening stiffness, mortar elastic modulus, length of mortar filling layer void, and pier settlement, the test points were designed by the Box-Behnken method based on Design-Expert software. The coupled dynamic model was calculated, and the support vector regression (SVR) nonlinear mapping model of the wheel-rail system was established. The learning, prediction, and verification were carried out. Finally, the reliable probability of the amplification coefficient distribution of the response index of the train and structure in different ranges was obtained based on the SVR nonlinear mapping model and Latin hypercube sampling method. The limit of the length of the mortar filling layer void was, thus, obtained. The results show that the SVR nonlinear mapping model developed in this paper has a high fitting accuracy of 0.993, and the computational efficiency is significantly improved by 99.86%. It can be used to calculate the dynamic response of the wheel-rail system. The length of the mortar filling layer void significantly affects the wheel-rail vertical force, wheel weight load reduction ratio, rail vertical displacement, and track plate vertical displacement. The dynamic response of the track structure has a more significant effect on the limit value of the length of the mortar filling layer void than the dynamic response of the vehicle, and the rail vertical displacement is the most obvious. At 250 km/h – 350 km/h train running speed, the limit values of grade Ⅰ, Ⅱ, and Ⅲ of the lengths of the mortar filling layer void are 3.932 m, 4.337 m, and 4.766 m, respectively. The results can provide some reference for the long-term service performance reliability of the ballastless track-bridge system of HRS.

Simple and green fabrication of a biomass-derived N and O self-doped hierarchical porous carbon via a self-activation route for supercapacitor application

Yang Binbin,Zhang Deyi,He Jingjing,Wang Yuling,Wang Kunjie,Li Hongxia,Wang Yi,Miao Lei,Ren Ruiye,Xie Mei 한국탄소학회 2020 Carbon Letters Vol.30 No.6

To meet the increased performance and cost requirements of commercial supercapacitor, a N and O self-doped hierarchical porous carbon is fabricated via a green and simple self-activation route utilizing leaves of wild hollyhock as raw materials. Comparing to commercial activated carbon, the reported material exhibits some marked merits, such as simple and green fabrication process, low cost, and superior capacitance performance. The specifc surface area of the obtained N and O co�doped hierarchical porous carbon arrives 954 m2 g−1, and the content of the self-doped nitrogen and oxygen reaches 2.64 at.% and 7.38 at.%, respectively. The specifc capacitance of the obtained material reaches 226 F g−1 while the specifc capacitance of the symmetric supercapacitor arrives 47.3 F g−1. Meanwhile, more than 90.3% of initial specifc capacitance is kept under a current density of 20 A g−1, and no arresting degradation is observed for capacitance after 5000 times cycle, perfectly demonstrating the excellent cycle and rate capability of the obtained material. The obtained N and O co-doped hierarchical porous carbon are expected to be an ideal substitution for commercial activated carbon.

Supercapacitors based on a nitrogen doped hierarchical porous carbon fabricated by self-activation of biomass: excellent rate capability and cycle stability

Zhang Zhijian,He Jingjing,Tang Xingchang,Wang Yuling,Yang Binbin,Wang Kunjie,Zhang Deyi 한국탄소학회 2019 Carbon Letters Vol.29 No.6

Energy and environmental are always two major challenges for the sustainable development of the modern human being. For avoiding the serious environmental pollution caused in the fabrication process of porous carbon, a popular energy storage material, we reported a facile, green and activating agent free route hereby directly carbonizing a special biomass, Glebionis coronaria. A nitrogen doped hierarchical porous carbon with a specific surface area of up to 1007 m2 g−1 and a N doping content of up to 2.65 at.% was facilely fabricated by employing the above route. Benefiting from the peculiarly hierarchical porous morphology, enhanced wettability and improved conductivity, the obtained material exhibits superior capacitance performance, which capacitance reaches up to 205 F g−1 under two-electrode configuration, and no capacitance loss is observed after 5000 cycles. Meanwhile, the capacitance retention of the obtained material arrives up to 95.0% even under a high current density of 20 A g−1, illuminating its excellent rate capability. The fabricated nitrogen-doped hierarchical porous carbon with larger capacitance than commercial activated carbon, excellent rate capability and cycle stability is an ideal cost-efficient substitution of commercial activated carbon for supercapacitor application.

Hybrid ceramics-based cancer theranostics

Guan Qingwen,He Binbin,Huang Jie,Lu Helen H.,Wang Min 한국세라믹학회 2022 한국세라믹학회지 Vol.59 No.4

Cancer is a major threat to human lives. Early detection and precisely targeted therapy/therapies for cancer is the most eff ective way to reduce the diffi culties (e.g., side eff ects, low survival rate, etc.) in treating cancer. To enable eff ective can- cer detection and treatment, ceramic biomaterials have been intensively and extensively investigated owing to their good biocompatibility, high bioactivity, suitable biodegradability and other distinctive properties that are required for medical devices in oncology. Through hybridization with other materials and loading of imaging agents and therapeutic agents, nanobioceramics can form multifunctional nanodevices to simultaneously provide diagnostic and therapeutic functions for cancer patients, and these nanodevices are known as hybrid ceramics-based cancer theranostics. In this review, the recent developments of hybrid ceramics-based cancer theranostics, which include the key aspects such as their preparation, bio- logical evaluation and applications, are summarized and discussed. The challenges and future perspectives for the clinical translation of hybrid ceramics-based cancer theranostics are also discussed. It is believed that the potential of hybrid ceramic nanoparticles as cancer theranostics is high and that the future of these theranostics is bright despite the diffi culties along the way for their clinical translation.

Supercapacitors based on a nitrogen doped hierarchical porous carbon fabricated by self‑activation of biomass: excellent rate capability and cycle stability

Zhijian Zhang,Jingjing He,Xingchang Tang,Yuling Wang,Binbin Yang,Kunjie Wang,Deyi Zhang 한국탄소학회 2019 Carbon Letters Vol.29 No.6

Energy and environmental are always two major challenges for the sustainable development of the modern human being. For avoiding the serious environmental pollution caused in the fabrication process of porous carbon, a popular energy storage material, we reported a facile, green and activating agent free route hereby directly carbonizing a special biomass, Glebionis coronaria. A nitrogen doped hierarchical porous carbon with a specific surface area of up to 1007 m2 g−1 and a N doping content of up to 2.65 at.% was facilely fabricated by employing the above route. Benefiting from the peculiarly hierarchical porous morphology, enhanced wettability and improved conductivity, the obtained material exhibits superior capacitance performance, which capacitance reaches up to 205 F g−1 under two-electrode configuration, and no capacitance loss is observed after 5000 cycles. Meanwhile, the capacitance retention of the obtained material arrives up to 95.0% even under a high current density of 20 A g−1, illuminating its excellent rate capability. The fabricated nitrogen-doped hierarchical porous carbon with larger capacitance than commercial activated carbon, excellent rate capability and cycle stability is an ideal cost-efficient substitution of commercial activated carbon for supercapacitor application.

Establishment of NOx Concentration Model at the Outlet of SCR Denitrification System for Alkali Recovery Furnace Flue Gas Based on Improved LSSVM

Yan Li,Zhen Hu,Binbin He,Qian Chen 한국펄프·종이공학회 2021 펄프.종이기술 Vol.53 No.5

Application of the body force method in the rim driven thruster

Cai Boao,Tian Binbin,Qiu Liaoyuan,Xu Qing,Mao Xiaofei,He Wei,Chai Wei 대한조선학회 2022 International Journal of Naval Architecture and Oc Vol.14 No.1

The Rim Driven Thruster (RDT) has become a popular ship propulsion system in recent years. Due to the complex structure of RDT, a great number of computational resources are required to study the interaction between RDT and hull by adopting the discretized propeller method. This research looks into a modified body force method which is suitable for the RDT. To simulate self-propulsion of a trawler with a rim driven thruster, the Reynolds-averaged NaviereStokes (RANS) solver is used. In the modified body force method, three virtual disks are adopted to replace the propeller and rim rotors. Before correction, the interactions among the duct, the rim rotors and the propeller were studied. Through the analysis, it is found that the most suitable scheme is to take the open water curves of the propeller, of the “rotors þ duct” and of the RDT as the references for modification. The ducted virtual disks open water curve is modified in open water simulations until the result is consistent with the RDT open water calculation results. When used to self-propulsion simulation, the modified body force method is accurate and can roughly characterize the flow fields. The modified body force method saves a huge number of grids when compared to the discretized propeller method. Furthermore, the interaction between the ship and the RDT can be accurately modeled, which is critical for quickly predicting self-propulsion in ships equipped with rim driven thrusters. Finally, the modified body force method in this work is named as the body force RDT method.

Analysis on natural vibration characteristics of steel-concrete composite truss beam

Lizhong Jiang,Yulin Feng,Wangbao Zhou,Binbin He 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.26 No.1

In order to study the natural vibration characteristics of steel-concrete composite truss beam (SCCTB), the influence of multiple factors such as interface slip, shear deformation and moment of inertia are considered. Afterwards, based on the Hamilton principle the vibration control differential equation and natural boundary conditions of SCCTB are deduced. By solving SCCTB differential equations of vibration control, an analytical calculation method is proposed for analyzing the natural vibration characteristics of SCCTB. The natural frequencies of SCCTBs with different degrees of shear connection and effective lengths are calculated by using the analytical method, and the results are compared against those obtained from ANSYS finite element numerical calculation method. The results show that the analytical method considering the influence factors such as interface slip, shear deformation and moment of inertia are in good agreement with those obtained from ANSYS finite element numerical calculation method. This evidences the correctness of the analytical method and show that the method proposed exhibits improvement over the previously developed theories for the natural vibration characteristics of SCCTB. Finally, based on the analytical method, the influence factors of SCCTB natural vibration characteristics are analyzed. The results indicate that the influence of interface slip stiffness on SCCTB's natural frequency is more than 10% and therefore cannot be neglected. Moreover, shear deformation has an effect of more than 35% on SCCTB’s natural frequency and the effect cannot be ignored either in this case too.

Vibration characteristic analysis of high-speed railway simply supported beam bridge-track structure system

Lizhong Jiang,Yulin Feng,Wangbao Zhou,Binbin He 국제구조공학회 2019 Steel and Composite Structures, An International J Vol.31 No.6

Based on the energy-variational principle, a coupling vibration analysis model of high-speed railway simply supported beam bridge-track structure system (HSRBTS) was established by considering the effect of shear deformation. The vibration differential equation and natural boundary conditions of HSRBTS were derived by considering the interlayer slip effect. Then, an analytic calculation method for the natural vibration frequency of this system was obtained. By taking two simply supported beam bridges of high-speed railway of 24 m and 32 m in span as examples, ANSYS and MIDAS finite-element numerical calculation methods were compared with the analytic method established in this paper. The calculation results show that two of them agree well with each other, validating the analytic method reported in this paper. The analytic method established in this study was used to evaluate the natural vibration characteristics of HSRBTS under different interlayer stiffness and length of rails at different subgrade sections. The results show that the vertical interlayer compressive stiffness had a great influence on the high-order natural vibration frequency of HSRBTS, and the effect of longitudinal interlayer slip stiffness on the natural vibration frequency of HSRBTS could be ignored. Under different vertical interlayer stiffness conditions, the subgrade section of HSRBTS has a critical rail length, and the critical length of rail at subgrade section decreases with the increase in vertical interlayer compressive stiffness.