A ‘‘micro-explosion” strategy for preparing membranes with high porosity, permeability, and dye/salt separation efficiency

Xinyang Li,Ligang Lin,Zitian Li,Jing Yang,Wensong Ma,Xu Yang,Xiaopeng Li,Chunhong Wang,Qingping Xin,Kongyin Zhao 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.119 No.-

In this study, inspired by ‘‘micro-explosion” strategies, a separation membrane with high porosity andpermeability, and highly efficient separation performance was prepared. With the use of polyvinylidenefluoride (Solvay6015) as membrane material, azodicarbonamide (AC) as an ‘‘explosion center point” tothe casting membrane solution, and NaOH as an ‘‘external stimulus” in the coagulation bath, the twochemicals undergo in-situ foaming reaction to form a loose nanofiltration membrane. FTIR, XPS, andTGA results demonstrated that the decomposition of AC was complete, which produced gases thatincreased the porosity of the membrane. The optimized membrane has a higher flux(101.72 L m2 h1 at 0.3 Mpa), higher negative surface charge, and better mechanical properties underthe premise of separating CR/NaCl. In the separation of pollutants with different molecular weights,the permeation flux of the optimized membrane increased by more than double. This foaming technologywas also applied to another membrane material, ethylene vinyl alcohol, from which we found that themembrane also had higher porosity and better permeability. Together, this paper presents an in-situfoaming method for preparing separation membranes and lays the foundation for solving the trade-offbetween membrane permeability and rejection in dye/salt separation.

Insensitive High Cyclotrimethylenetrinitramine (RDX) Nanostructured Explosives Derived from Solvent/Nonsolvent Method in a Bacterial Cellulose (BC) Gelatin Matrix

Qingping Luo,Chonghua Pei,Guixiang Liu,Yongjun Ma,Zhaoqian Li 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2015 NANO Vol.10 No.3

Cyclotrimethylenetrinitramine (RDX) is an energetic material (EM) from the class of cyclic nitroamine explosive widely used in military applications because of its excellent integral properties. Using bacterial cellulose (BC) gelatin with a three-dimensional network as a matrix, N,Ndimethyllformamide (DMF) as the solvent of RDX, the RDX nanostructured explosives were prepared through the solvent/nonsolvent method. It was found that the solvent had a great impact on the crystallization of RDX in the solution and the RDX content in the nanostructured explosive. The RDX particles in the nanostructured explosives smoothly coated to the nanofibers of BC gelatin network at high RDX concentrations, and the granularity distributions of RDX in the nanostructured explosives were very uniform in the range of 30–50 nm. The average contents of the RDX in the nanostructured explosives are greater than 83 wt.% when the RDX concentrations of the soaked solutions are greater than 0.20 g/mL. The average content is approximately 91 wt.% when the RDX concentration is 0.30 g/mL. The decomposition temperatures of the RDX nanostructured explosives were found to decrease approximately to 20 C and their mechanical sensitivities decreased greatly compared to that of raw micro-size RDX. It opens a useful way to prepare nanostructured explosives with high energy and low mechanical sensitivity.

중추 신경계의 손상 및 재생 기전 연구를 위한 생체 외 에세이 방법

hu qingping,Hyung Joon Kim,Jeong Won Park,Berad vahidi,Jae Hwan Byun,Sudong Kim,Hyun Ryul Ryu,Yekyuong Cho,Noo Li Jeon 대한기계학회 2009 대한기계학회 춘추학술대회 Vol.2009 No.5

A Joint Allocation Algorithm of Computing and Communication Resources Based on Reinforcement Learning in MEC System

( Qinghua Liu ),( Qingping Li ) 한국정보처리학회 2021 Journal of information processing systems Vol.17 No.4

For the mobile edge computing (MEC) system supporting dense network, a joint allocation algorithm of computing and communication resources based on reinforcement learning is proposed. The energy consumption of task execution is defined as the maximum energy consumption of each user's task execution in the system. Considering the constraints of task unloading, power allocation, transmission rate and calculation resource allocation, the problem of joint task unloading and resource allocation is modeled as a problem of maximum task execution energy consumption minimization. As a mixed integer nonlinear programming problem, it is difficult to be directly solve by traditional optimization methods. This paper uses reinforcement learning algorithm to solve this problem. Then, the Markov decision-making process and the theoretical basis of reinforcement learning are introduced to provide a theoretical basis for the algorithm simulation experiment. Based on the algorithm of reinforcement learning and joint allocation of communication resources, the joint optimization of data task unloading and power control strategy is carried out for each terminal device, and the local computing model and task unloading model are built. The simulation results show that the total task computation cost of the proposed algorithm is 5%-10% less than that of the two comparison algorithms under the same task input. At the same time, the total task computation cost of the proposed algorithm is more than 5% less than that of the two new comparison algorithms.

3D Printing of Bioinspired Structural Materials with Fibers Induced by Doctor Blading Process

Luquan Ren,Bingqian Li,Zhengyi Song,Qingping Liu,Lei Ren,Xueli Zhou 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.6 No.1

Fiber is a crucial element in biological micro-structural materials. Replication of fiber-reinforced composites with analogous architectures of their natural counterparts has caused widespread academic concern. Recent researches indicate 3D printing technology has the potential to produce biomimetic structural materials. The aim of this study is to develop a process to fabricate fiber-reinforced composites with ordered yet spatially tunable fiber arrangement. Specifically, we present a method to align fibers during the 3D printing of fiber-reinforced composites. A modified slurry-based stereolithography process was developed, and the fibers in the fiber–resin mixture were aligned by Shear force produced during the spreading of slurry. We investigated the influence of relative factors on fiber orientation, and two models were used to uncover the internal mechanism. By controlling the speed and the direction of the moving blade, the patterns that fibers were arranged can be freely programmed. Therefore, we have extracted bioinspired sinusoidal and zigzag design motifs to analyze their mechanical properties compared with non-bioinspired motifs. The proposed method is relatively material agnostic, more efficient and more facile. It thus provides a promising route to fabricate fiber-reinforced composites, and has potential to be adopted in biological structures researches and industrial applications.

Preparation and properties of CNTs-Cu hybrids/epoxy superhydrophobic and anticorrosive coatings

Zhongbo Zhu,Shumei Kang,Hua Chen,Qingping Zhao,Zhaokang Huo,Pengyu Li,Qidong Cao,Chenshuo Lu 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.119 No.-

In this work, hydrophobized copper powders combined siloxane-modified carbon nanotubes(SHMWCNTs) to obtain intertwined hybrids of carbon nanotubes and copper (CNTs-Cu hybrids), andsuperhydrophobic CNTs-Cu hybrids/epoxy coatings were prepared on the surface of AH36 carbon steelby drop coating. The surface morphology and wettability of coatings were changed by adjusting the ratiosof SHMWCNTs to hydrophobized copper powders. The obtained coating can show a water contact angleof 167.2, a water sliding angle of 2.9, a plant oil contact angle of 134.3, and self-cleaning properties. Thecoating maintains superhydrophobicity after 300 tape-peeling times, exhibiting excellent mechanicaldurability. The fouled area percentages of chlorella on the coating and a pure epoxy resin were 0.23(±0.07)% and 12.18(±1.22)%, respectively, displaying anti-biofouling resistances. The coating has excellentcorrosion resistance, and its corrosion current density reached 9.55 10-8 A/cm2.

Norepinephrine/β2-Adrenergic Receptor Pathway Promotes the Cell Proliferation and Nerve Growth Factor Production in Triple-Negative Breast Cancer

Meihua Jin,Yan Wang,Tingting Zhou,Wenzhe Li,Qingping Wen 한국유방암학회 2023 Journal of breast cancer Vol.26 No.3

Purpose: Invasive ductal carcinoma (IDC) accounts for 90% of triple-negative breast cancer (TNBC). IDC is mainly derived from the breast ductal epithelium which is innervated by the 4th to 6th thoracic sympathetic nerves. However, little is known about the contribution of the interactions between sympathetic nerves and breast cancer cells to the malignant progression of TNBC. Methods: The expression levels of the β2-adrenergic receptor (β2-AR, encoded by ADRB2 gene), nerve growth factor (NGF), and tropomyosin receptor kinase A (TrkA) were determined using immunohistochemistry (IHC). NGF expression levels in the serum were compared by enzyme-linked immunosorbent assay (ELISA). Cell proliferation was assessed using the Cell Counting Kit-8 assay. The β2-AR, NGF, p-ERK, and p-CERB expression levels were determined using western blotting. TNBC cells and neuronal cells of the dorsal root ganglion (DRG) in 2-day-old Sprague Dawley rats were co-cultured. Using norepinephrine (NE), NGF, and β2-AR, NGF/TrkA blocker pretreatments, the axon growth of each group of DRG neuron cells was detected by immunofluorescence analysis. Results: The sympathetic adrenergic neurotransmitter NE activated the ERK signaling pathway in TNBC cells. NE/β2-AR signaling promotes NGF secretion. NGF further facilitates the malignant progression of TNBC by increasing sympathetic neurogenesis. In the co-culture assay, the sympathetic adrenergic NE/β2-AR signal pathway also enhanced NGF secretion. NGF binds TrkA in DRG neurons and promotes axonal growth. Conclusion: These results suggest that NE/β2-AR pathway promotes cell proliferation and NGF production in triple-negative breast cancer.

Polyaniline/Cerium Oxide Hybrid Modified Carbon Paste Electrode for Non-Enzymatic Glucose Detection

Jie Zhang,Panpan Guan,Yongjian Li,Wei Li,Qingping Guo 대한화학회 2016 Bulletin of the Korean Chemical Society Vol.37 No.7

Adsorption resin/polyethersulfone membrane used for plasma separation and middle molecular toxins adsorption

Xiaoyang Hou,Lilan Huang,Han Zhang,Qingping Xin,Hong Li,Hui Ye,Yuzhong Zhang 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.123 No.-

Accumulation of endogenous and exogenous toxins in patients with chronic kidney disease increases thekidney burden. The newly developed plasma separation adsorption membranes provide a new model forthe removal of middle molecular toxins. In this study, the adsorption resin LX-1000H is physically pulverizedand blended into polyethersulfone matrixes to prepare adsorption resin/polyethersulfone (AR/PES) membranes by nonsolvent-induced phase separation for plasma separation and middle moleculartoxins absorption. The results show that the static adsorption capacity of AR/PES membrane for lysozyme(a typical mimic of middle molecular toxins) is up to 108.90 mg/g, which is 4 times that of AR. The maximumdynamic adsorption capacity reaches 102.80 mg/g, which is 93.4% of static adsorption. The adsorptionprocess is more consistent with the Langmuir model and the quasi-first-order kinetic model. Thepermeability of bovine serum albumin in simulated blood surpasses 90% and the cattle blood separatedby AR/PES membrane is colorless and transparent. The AR/PES membrane surface presents electronegativeat pH 7.4 and the water wettability is enhanced with the doping amount. No hemolysis and negligibleleakage indicated favorable hemocompatibility. This paper is devoted to providing a strategy forplasma separation and adsorption membranes.

Constructing mixed matrix membranes for CO2 separation based on light lanthanide fluoride nanosheets with mesoporous structure

Yanli Zhang,Meixue Zhao,Xu Li,Qingping Xin,Xiaoli Ding,Lizhi Zhao,Hui Ye,Ligang Lin,Hong Li,Yuzhong Zhang 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.125 No.-

The incorporation of porous nano-fillers into mixed matrix membranes (MMMs) has a great impact onCO2 separation. In this study, a series of F-Ln (Ln is the Light Lanthanide, Ln = La, Ce, Pr, Nd) nanosheetswith mesoporous structure was fabricated as a filler in Pebax1657 matrix to improve the performance ofCO2 separation. F-Ln nanosheets are uniformly distributed in the membrane and the mesoporous structurecan construct multiple channels for CO2 fast transport in Pebax/F-Ln MMMs. The pore diameter ofnanosheet is in order: F-La > F-Ce > F-Pr > F-Nd, and the smaller pore diameter of nanosheets is beneficialto improve the CO2 separation performance. In humidified conditions, Pebax/F-Nd-6 MMMs show optimumseparation performance among MMMs, and the CO2 permeability is up to 1265 Barrer and CO2/CH4selectivity is 36.7, which are 2.3 times and 1.9 times higher than pure Pebax and approaches 2019 upperbound. Meanwhile, to demonstrate the potential universal applicability of F-Ln nanosheets in CO2 separation,XLPEO/F-Ce MMMs were fabricated to separate CO2/N2 and the performance exceeds the 2019upper bound. The efficient CO2 separation performance of 2D F-Ln nanosheets with mesoporous structurein membranes reveals the potential application of these nanosheets in industrial CO2 separation.