Effects of solvent extraction on the microstructure of bituminous coal-based graphite

Wang Lipeng,Yao Zongxu,Guo Zhimin,Shen Xiaofeng,Li Zhiang,Zhou Zhengqi,Wang Yuling,Yang Jian-Guo 한국탄소학회 2022 Carbon Letters Vol.32 No.3

Coal-based graphite has become the main material of emerging industries. The microstructure of coal-based graphite plays an important role in its applications in many fields. In this paper, the effect of carbon disulfide/N-methyl-2-pyrrolidone solvent mixture extraction on the microstructure of bituminous coal-based graphite was systematically studied through preliminary extraction coupled with high-temperature graphitization. The graphitization degree g (75.65%) of the coal residue-based graphite was significantly higher than that of the raw coal-based graphite. The crystallite size La of the coal residue-based graphite was reduced by 47.06% compared with the raw coal-based graphite. The ID/ IG value of the coal residue-based graphite is smaller than that of the raw coal-based graphite. The specific surface area (16.72 m2/g) and total pore volume (0.0567 m3/g) of the coal residue-based graphite are increased in varying degrees compared with the raw coal-based graphite. This study found a carbon source that can be used to prepare coal-based graphite with high graphitization degree. The results are expected to provide a theoretical basis for further clean and efficient utilization of the coal residue resources.

Correction to: Effects of solvent extraction on the microstructure of bituminous coal‑based graphite

Lipeng Wang,Zongxu Yao,Zhimin Guo,Xiaofeng Shen,Zhiang Li,Zhengqi Zhou,Yuling Wang,Jian‑Guo Yang 한국탄소학회 2022 Carbon Letters Vol.32 No.3

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.

Molecular cloning of the Bombus terrestris bumblebee venom protein phospholipase A2 and its anti-leukemia effects on K562 cells

Yuling Qiu,Yali Chen,Haiyang Yu,Qianxiang Zhou,Ran Wang,Meihua Jin,Dexin Kong 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.2

Bee venom has been used for treating various diseases for a long time. However, the bioactive constituents of bee venom and its mechanisms remain poorly understood. In the present study, phospholipase A2 (Bt-PLA2) cDNA was cloned, and a mature form of Bt-PLA2 was purified from bumblebee venom (Bombus terrestris). The differentiation induction and apoptosis induction activities of Bt-PLA2 on chronic myelogenous leukemia (CML) K562 cells were also evaluated. Bt-PLA2 cDNA has 540 nucleotides that encode a 180-amino-acid protein. The purified, mature form of Bt-PLA2 was an 18-kDa protein, and it inhibited K562 cell growth, determined by an IC50 value of 29.5 ng/μl. Moreover, Bt-PLA2 induced erythroid differentiation of K562 cells in a dose-dependent manner, and this was supplemented with the upregulation of glycophorin A (GPA) mRNA expression. Bt-PLA2- induced apoptosis, analyzed by DAPI staining, was correlated with the result analyzed by AnnexinV-FITC/PI binding. Furthermore, activation of caspase 3 and poly ADP-ribose polymerase (PARP) and inhibition of p-Akt, determined by western blot, further demonstrated that Bt-PLA2 induced apoptosis mainly through the Akt pathway. The parallel induction of erythroblasts differentiation of K562 cells and apoptosis due to Bt-PLA2 treatment demonstrated the potential use of Bt-PLA2 as an anti-leukemia drug lead.

Ground type-I collagen—a focused study on its fibrillogenesis behavior and bioactivity in vitro

Yuling Xu,Lei Dai,Ke Li,Jialin Liu,Haibo Wang,Lang He,Chengzhi Xu,Benmei Wei,Juntao Zhang 한국고분자학회 2023 Macromolecular Research Vol.31 No.1

Take bovine tendon type-I collagen as the raw material, we pretreated it by freezing and then grinding the macromolecule at a low temperature (4–10 °C). Effects of the grinding process on the molecular structure, water solubility, fibrillogenesis behavior in vitro and biological activity of collagen were systematically prospected. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) results revealed that the collagen had typical structural characteristics of type-I collagen; moreover, grinding treatment gave rise to partially degraded collagen molecules which took on continuous bands with lower molecular weights different from α1 and α2. More strikingly, the degradation degree positively corresponded to the grinding duration. Circular dichroism (CD) analysis manifested that with extended grinding, intensities of both the positive and negative peaks for collagen samples shrunk. Interestingly, grinding also contributed to improved water solubility of collagen. The water solubility of the sample ground for 20 min (COL20) was 1.91 mg/mL, which is about 6 times higher than that of the natural collagen sample (0.28 mg/mL). Amid the study concerning the fibrillogenesis behavior, turbidity and rheological data collaboratively demonstrated that with prolonged grinding time, the assembly rate and degree of the sample plunged. Assembled gel from the ground collagen with finer fibrils was also observed in scanning electron microscope (SEM), which further embraced the conclusion aforementioned in fibrillogenesis kinetics. Cell experiments corroborated that the grinding process can be harnessed to manipulate the cell proliferation promoting ability of collagen. Simultaneously, further dissection of COL20 with the best biological activity clarified that the water-soluble part and water-insoluble part of COL20 had distinct aptitudes as to promoting cell proliferation as well as inhibiting the growth of liver cancer cells.

Marein Prevented LPS-Induced Osteoclastogenesis by Regulating the NF-κB Pathway In Vitro

( Yuling Li ),( Jing Zhang ),( Caiping Yan ),( Qian Chen ),( Chao Xiang ),( Qingyan Zhang ),( Xingkuan Wang ),( Ke Jiang ) 한국미생물생명공학회 2022 Journal of microbiology and biotechnology Vol.32 No.2

Many bone diseases such as osteolysis, osteomyelitis, and septic arthritis are caused by gramnegative bacterial infection, and lipopolysaccharide (LPS), a bacterial product, plays an essential role in this process. Drugs that inhibit LPS-induced osteoclastogenesis are urgently needed to prevent bone destruction in infective bone diseases. Marein, a major bioactive compound of Coreopsis tinctoria, possesses anti-oxidative, anti-inflammatory, anti-hypertensive, antihyperlipidemic, and anti-diabetic effects. In this study, we measured the effect of marein on RAW264.7 cells by CCK-8 assay and used TRAP staining to determine osteoclastogenesis. The levels of osteoclast-related genes and NF-κB-related proteins were then analyzed by western blot, and the levels of pro-inflammatory cytokines were quantified by ELISA. Our results showed that marein inhibited LPS-induced osteoclast formation by osteoclast precursor RAW264.7 cells. The effect of marein was related to its inhibitory function on expressions of pro-inflammatory cytokines and osteoclast-related genes containing RANK, TRAF6, MMP-9, CK, and CAII. Additionally, marein leads to markedly inhibited NF-κB signaling pathway activation in LPS-induced RAW264.7 cells. Concurrently, when the NF-κB signaling pathway was inhibited, osteoclast formation and proinflammatory cytokine expression were decreased. Collectively, marein could inhibit LPS-induced osteoclast formation in RAW264.7 cells via regulating the NF-κB signaling pathway. Our data demonstrate that marein might be a potential drug for bacteria-induced bone destruction disease. Our findings provide new insights into LPS-induced bone disease.

Creep Properties of a Nickel-Based Single Crystal Superalloy with Low Density

Yuling Du,Zihao Tan,Yanhong Yang,Xinguang Wang,Yizhou Zhou,Jingguo Li,Xiaofeng Sun 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.12

A novel nickel-based single crystal superalloy with low density had been designed and the creep deformation mechanismsof the experiment alloy under two conditions (1050 °C/200 MPa and 1100 °C/137 MPa) had been systematically discussed. The topological inversion had been observed after fracture under the above two conditions. The effects of temperature andstress on creep life of the experiment alloy had been found no significant difference under the two conditions. It was indicatedthat the small decrease in temperature exerted limited influence on the creep behaviors of single crystal superalloys in therange of high temperature.

Silk Nonwoven: Recycling and Upcycling of Waste Silk into Bio-based Materials with High Value-Added Properties

Hongchang Wang,Liyao Cao,Yuling Li,Run Wen,Guangbiao Xu 한국섬유공학회 2023 Fibers and polymers Vol.24 No.10

With the increasing awareness of human environmental protection, the development of biodegradable bio-based materials has received more attention. As the off-cuts of silk, a natural protein fiber, waste silk still retains excellent properties such as biodegradability and biocompatibility, recycling and utilization of waste silk is currently very limited. To find a possible method to recycle low-cost waste silk and process it into high-value-added products, in this work, the waste silk from the silk spinning process was prepared into silk nonwoven (SN) with excellent air permeability, softness, water–oil amphiphilicity, biodegradability, and ultraviolet resistance by the wet laid process. The results showed that the uniform SN could be prepared when the alkali concentration was higher than 0.6%. The permeability of SN is higher than 80 mm/s, and the bending stiffness is lower than 0.085gf·cm2/cm. Notably, SN possesses entanglement at both fiber and fibril levels, enabling it to achieve a base strength of 0.58 MPa without additional reinforcement. The water contact angle and oil contact angle of SN were below 40° and 50°, respectively. The ultraviolet protection of SN-0.6 was classified as very good, with a degradation rate of 4.31% of SN-0.6 after 30 days of burial. The present research shows that silk nonwoven is a potential bio-based material with promising applications in the field of packaging and cleaning.

Weak fault detection for wind turbine bearing based on ACYCBD and IESB

Xiaolong Wang,Xiaoli Yan,Yuling He 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.4

To detect the rolling bearing fault of a wind turbine at incipient injury phase, a novel method combining adaptive cyclostationary blind deconvolution (ACYCBD) with instantaneous energy slice bispectrum (IESB) is proposed. Cuckoo search algorithm (CSA) is fused with cyclostationary blind deconvolution (CYCBD) to optimize cyclic frequency and filter length parameters, and the satisfied processing result is able to adaptively use this developed ACYCBD method. Besides, fusing the complementary superiorities of frequency weighted energy operator and slice bispectrum, a new frequency domain analysis method named IESB is put forward to identify the characteristic frequency components. During fault diagnosis, the deconvolution signal with higher signal to noise ratio is first separated from the collected signal by applying ACYCBD method. However, owing to the intense background noises, external interferences still remain in the deconvolution signal. Then the IESB is further used as a post-processing method, the residual noises are suppressed effectively, and the characteristic spectral lines are highlighted immensely. In the end, the incipient fault injury of wind turbine bearing can be diagnosed by analyzing the acquired instantaneous energy slice bispectrum. The analyzed results of wind turbine bearing fault signals from the experimental rig and the actual engineering testing field demonstrate the feasibility and the superiority of this novel detection method.

Diagnosis of compound faults of rolling bearings through adaptive maximum correlated kurtosis deconvolution

Guiji Tang,Xiaolong Wang,Yuling He 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.1

This paper proposes a new diagnosis method based on Adaptive maximum correlated kurtosis deconvolution (AMCKD) for accurateidentification of compound faults of rolling bearings. The AMCKD method combines the powerful capability of cuckoo search algorithmfor global optimization with the advantage of Maximum correlated kurtosis deconvolution (MCKD) for impact signal extraction. In contrastto traditional methods, such as direct envelop spectrum, Discrete wavelet transform (DWT), and empirical mode decomposition, theproposed method extracts each fault signal related to the single failed part from the compound fault signals and effectively separates thecoupled fault features. First, the original signal is processed using AMCKD method. Demodulation operation is then performed on theobtained single fault signal, and the envelope spectrum is calculated to identify the characteristic frequency information. Verification isperformed on simulated and experimental signals. Results show that the proposed method is more suitable for detecting compound faultsin rolling bearings compared with traditional methods. This research provides a basis for improving the monitoring and diagnosis precisionof rolling bearings.