Imperatorin Sustained-release Tablets: In Vitro and Pharmacokinetic Studies

Jingjing Pan,Wen Lu,Changhui Li,Sicen Wang,Langchong He 대한약학회 2010 Archives of Pharmacal Research Vol.33 No.8

We prepared and evaluated imperatorin (IMP) sustained-release tablets. IMP is an active compound in Angelica dahuricae, a Chinese herbal medicine. We used different polymers, such as hydroxypropyl methylcellulose (HPMC K4M, K15M, and K100M), carbopol 934P, sodium carboxymethyl cellulose (CMC-Na), and their combinations to prepare the matrix tablets and achieve the desired sustained release profile. The in vitro release profiles of these formulations were examined and fit to various kinetic release models. We also tested the effects of polymer combination ratios on the in vitro release rate. In vivo studies were performed for the optimized formulation in six beagle dogs, and pharmacokinetic parameters were compared with plain IMP tablets. IMP sustained-release tablets exhibited a more sustained plasma concentration than the plain tablets, with a relative bioavailability of 127.25%. The in vitro releases rates and in vivo absorption correlated for the initial 8 hours. These results demonstrate that the sustained-release tablet system can effectively control the release of IMP.

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.

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.

Breathing-based Continuous Non-intrusive User Verification Leveraging Commodity WiFi

Huan Dai,Jingjing Jiang,Jiaju Ma,He Huang,Hongbo Liu 한국통신학회 2022 Journal of communications and networks Vol.24 No.2

This paper opens up a new pathway of the utilityof breathing pattern for user verification. We demonstrate thatit is possible to capture people’s breathing pattern leveragingcommodity WiFi devices. While prior solutions for biometricsbaseduser recognition usually require dedicated devices (e.g.,video cameras or IR sensors), this paper introduces the firstgeneral, low-cost breathing-based user verification system usingcommodity WiFi devices. The proposed system is based onthe fact that the breathing pattern always keeps consistentfor the same user but distinct among different people. Ourinnovative method successfully extracts the breathing patternof different people based on channel state information of WiFisignal to facilitate user verification. The prototype study usingtwo commodity WiFi devices can differentiate people with anaverage verification accuracy over 90%, suggesting that ourbreathing-based user verification system using commerical offthe-shelf (COTS) WiFi is promising to be one of the most criticalmethods in biometrics.

Parameter Identification of 3R-C Equivalent Circuit Model Based on Full Life Cycle Database

Yanbo Che,Jingjing Jia,Yuexin Yang,Shaohui Wang,Wei He 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.4

The energy density, power density and ohm resistance of battery change significantly as results of battery aging, which lead to decrease in the accuracy of the equivalent model. A parameter identification method of the equivale6nt circuit model with 3 R-C branches based on the test database of battery life cycle is proposed in this paper. This database is built on the basis of experiments such as updating of available capacity, charging and discharging tests at different rates and relaxation characteristics tests. It can realize regular update and calibration of key parameters like SOH, so as to ensure the reliability of parameters identified. Taking SOH, SOC and T as independent variables, lookup table method is adopted to set initial value for the parameter matrix. Meanwhile, in order to ensure the validity of the model, the least square method based on variable forgetting factor is adopted for optimizing to complete the identification of equivalent model parameters. By comparing the simulation data with measured data for charging and discharging experiments of Li-ion battery, the effectiveness of the full life cycle database and the model are verified.

Fabrication of a water-retaining, slow-release fertilizer based on nanocomposite double-network hydrogels via ion-crosslinking and free radical polymerization

Yanmin Shen,He Wang,Zijun Liu,Weikun Li,Yuhua Liu,Jingjing Li,Hong-Liang Wei,Huayun Han 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.93 No.-

A new type of water-retaining, slow-release fertilizer (WSF) based on double-network hydrogels wasfabricated via the ion-crosslinking of sodium carboxymethyl cellulose and the free radical polymeriza-tion of polymerizable β-cyclodextrin (MAH-CD), polyethylene glycol dimethacrylate (PEGDA), acrylamide(AM), and acrylic acid (AA) with urea-loaded halloysite as an additive. The effects of the AM to AAmonomer ratio, the halloysite content, the AlCl3 content and the MAH-CD content on the swelling ratiowere studied. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), andthermogravimetric analysis (TGA) were applied to characterize the structure and properties of the WSF. The swelling behavior and water retention capacity of the fertilizer were investigated using a classicgravimetric method. The experimental results indicated that the presence of halloysite nanotubes clearlyadjusted the swelling and release properties of the WSF. Kinetic modeling indicated that the swellingmechanism and slow release behavior were consistent with a Fickian diffusion mechanism. Form theconsiderations of its properties and raw materials, the fertilizer developed here has a good prospect ofapplication and extension.

智慧城市建设对碳排放水平的影响

Qiao, Yanyun,He, Jingjing 성균관대학교 성균중국연구소 2023 중국사회과학논총 Vol.5 No.2

本文以中国评定智慧城市为例,运用渐进式双重差分模型实证研究智慧 城市建设对减少碳排放的影响。基准回归结果表明,“智慧城市”的试点具有显著 的碳排放控制效应,多种稳健性检验的结果也再次印证了本文的结论。动态分析表 明,智慧城市的碳排放控制效应具有较长的政策时滞,大约到第三年政策的生态效 应逐渐显现。中介效应模型表明,智慧城市通过促进城市技术创新和高新技术产业 集聚进而削弱城市碳排放水平。调节效应模型表明,政府的环境规制行为强化了智 慧城市的碳排放控制效应,经济逐步转向高质量发展尚未对城市碳排放起到调节作 用。空间杜宾模型表明智慧城市的碳排放控制效应具有空间溢出性。本文的研究对 发展中国家解决城市化与低碳发展之间的矛盾具有参考价值,对发展中国家如何实 现低碳发展、发达国家进一步降低碳排放量具有借鉴意义,对于应对全球气候危机 也具有重要的现实意义。

Production of cyclic adenosine-3',5'-monophosphate by whole cell catalysis using recombinant Escherichia coli overexpressing adenylate cyclase

Hanjie Ying,Jingjing Xie,Nan Li,Ying He,Yong Chen,Xiaochun Chen,Jianxin Bai,Jinglan Wu 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.4

Adenylate cyclase (EC 4.6.1.1) catalyzes the formation of cyclic adenosine-3',5'-monophosphate (cAMP)from adenosine 5'-triphosphate (ATP). Recombinant Escherichia coli overexpressing adenylate cyclase was used to synthesize cAMP by whole cell catalysis. Some key parameters were examined during the catalytic process, while pH and Mg2+ were found to influence cAMP production significantly. Optimum conditions were pH 8.52 and 30 oC with 77.2 mM Mg2+ in 100 mM Tris-HCl buffer, including 0.25% Triton-X 100 as detergent and 30 mM pyruvate sodium as enzyme activator for 6 h. 14.93 g/L of cAMP was produced with a conversion rate of 91.5%. The current work provided a potential way for the industrial production of cAMP.

Effect of Fe nanoparticle-loaded sawdust carbon on catalytic pyrolysis of heavy oil

Yitang Zhong,Xiaodong Tang,Jingjing Li,Bin He,Zhiqi Zhang,Tingbing Chen 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.4

This work was focused on the synthesis and characterization of iron nanoparticle loaded sawdust carbon(Fe/SC) by low cost green synthesis approach and its application for catalytic pyrolysis of heavy oil. Fourier transforminfrared (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS),transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and inductively coupled plasmaoptical emission spectrometer (ICP-OES) methods were used to analyze the catalyst of Fe/SC. The properties of heavyoil before and after reaction were characterized by SARA analysis, FT-IR, gas chromatography-mass spectrometry (GCMS)and thermogravimetric analysis (TGA). The experimental results showed that after pyrolytic reaction at 350 oC for30 min with 0.1 wt% catalyst, the viscosity of heavy oil may decrease by 80.81% with a net efficiency of catalyst of20.68%. The catalyst of Fe/SC is promising, low cost, high efficiency, highly stable and eco-friendly for catalytic upgradingand viscosity reduction of heavy oil.

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.