Corrosion Resistance and Compressive Strength of Cemented Soil Mixed with Nano-Silica in Simulated Seawater Environment

Qing-Sheng Chen,Hongyu Zhang,Jianjun Ye,Gao-LiangTao,Sanjay Nimbalkar 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.4

Cemented soil structures are frequently exposed to the corrosive environment of seawater for an extended period, severely affecting their interior structure and mechanical qualities. This study presents laboratory-based approach to investigate the effect of nano-SiO2 on the structural and mechanical properties of cemented soil in a simulated seawater environment. The unconfined compressive strength (UCS), elastic modulus and other mechanical properties of cemented soil mixed with nano-SiO2 and ordinary silicate cemented soil were evaluated. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to deduce the crystalline composition and microstructure characteristics of the modified cemented soil. The results show that the addition of nano-SiO2 greatly increased the compressive strength and corrosion resistance of the cemented soil. In a 3C (105% salinity) simulated saltwater curing environment, the compressive strength of the cemented soil containing 2% nano-SiO2increased by 86% and 158% at 30days and 60days, respectively. XRD and SEM showed that nano-SiO2 enhanced the interface structure of cemented soil and increased the compactness of the cement-soil system. The current study demonstrates that nano-SiO2 could considerably improve the mechanical characteristics and corrosion resistance of cemented soil when exposed to simulated seawater.

Strength and Deformation Characteristics of Calcareous Sands Improved by PFA

Qing-Sheng Chen,Wan Peng,Gao-LiangTao,Sanjay Nimbalkar 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.1

Calcareous sand is widely distributed in the islands of the South China Sea, which could be promisingly used as the construction materials. However, particle breakage commonly occurs in calcareous sands, which may significantly influence their mechanical characteristics. To address these issues, an eco-friendly agent, i.e., polyurethane foam adhesive (PFA) is proposed to improve the engineering properties of calcareous sands, compared to the commonly used alkaline stabilizing agents (e.g., lime, cement). The objective of this work is to examine the effectiveness of using PFA in improving the strength-deformation properties of calcareous sand. A series of laboratory tests including direct shear tests, unconfined compression tests, and oedometer tests were performed on the calcareous sands improved by PFA. In addition, A scanning electron microscope (SEM) was conducted to reveal microstructural analysis of using PFA for calcareous sand. The experimental results provided insights into the shear strength, deformation modulus, as well as the micro-structural characteristics of improved calcareous sands with various PFA contents and particle size distributions.

Experimental Analysis and Evaluation of the Compressive Strength of Rubberized Concrete During Freeze–Thaw Cycles

Sheng Sun,Xiaoyan Han,Aijiu Chen,Qing Zhang,Zhihao Wang,Keliang Li 한국콘크리트학회 2023 International Journal of Concrete Structures and M Vol.17 No.4

Recycling scrap tires provides an alternative source of fine aggregates for the production of rubberized concrete and this will lead to significant increase in concrete frost resistance, environmental protection, and conservation of natural sand and gravel resources. In this paper, a total of 25 groups of rubberized concrete were produced by adding scrap tire rubber particles of different sizes, contents, and pretreatment methods to replace the fine aggregate, and their compressive strength during freeze–thaw cycles was studied from both the macro- and meso-perspectives. The results indicated that the decrease in concrete strength and weight was notably restricted by the presence of rubber particles during freeze–thaw cycles. The rubber fine aggregate with smaller particle sizes enhanced the concrete frost resistance more significantly, and the F100 of concrete with rubber particles of 1.0–2.0 mm increased from 76.6 to 86.5% by increasing the rubber content from 0.0 to 5.6%. The effects of rubber fine aggregate on concrete compressive strength during freeze–thaw cycles were quantified. On this basis, a forecast model for rubberized concrete compressive strength in freeze–thaw cycles was proposed, and the effects of the particle size, content, and pretreatment of the rubber particles were considered. The calculated results agreed well with the test results both in this study and the relevant peer studies, indicating that the model can provide a good reference for the design and engineering application of rubberized concrete in frigid environments.

Cytotoxic dibenzocyclooctadiene lignans from Kadsura coccinea

Qing-Jie Zhao,Yan Song,Hai-Sheng Chen 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.11

Three new dibenzocyclooctadiene lignans,kadusurain A–C (1–3), together with two known compoundskadsuphilin A (4) and B (5), were isolated from anEtOAc fraction of the 80 % acetone extract of Kadsuracoccinea (Lem.) A. C. Smith. Their structures wereestablished by 1D and 2D NMR techniques, and massspectroscopy. Anti-proliferative effect of isolated compoundswas evaluated against four human tumor cell lines(A549, HCT116, HL-60, and HepG2), and it was foundthat compound 1 exhibited significant antiproliferativeeffects with IC50 values ranging from 1.05 to 12.56 lg/ml.

Efficacy and Safety Profile of Combining Sorafenib with Chemotherapy in Patients with HER2-Negative Advanced Breast Cancer: A Meta-analysis

Jie Chen,Chun-Xiang Tian,Miao Yu,Qing Lv,Nan-Sheng Cheng,Zu Wang,Xi Wu 한국유방암학회 2014 Journal of breast cancer Vol.17 No.1

Purpose: The aim of the study was to evaluate the efficacy andsafety of combining sorafenib with chemotherapy in patients withhuman epidermal growth factor receptor 2 (HER2)-negative advancedbreast cancer. Methods: MEDLINE, EMBASE, CochraneCentral Register of Controlled Trials, American Society for ClinicalOncology abstracts, and European Society for Medical Oncologyabstracts were searched. Randomized clinical trials that comparedthe efficacy and safety of sorafenib plus chemotherapy inpatients with HER2-negative advanced breast cancer with placeboplus chemotherapy were eligible. The endpoints were progression-free survival (PFS), overall survival (OS), time to progression(TTP), duration of response (DOR), overall response rate(ORR), clinical benefits, and adverse effects. The meta-analysiswas performed using Review Manager 5.2.6 (The Nordic CochraneCentre), and the fixed-effect model weighted by the Mantel-Haenszel method was used. When considerable heterogeneitywas found (p<0.1), further analysis (subgroup analysis, sensitivityanalysis, or random-effect model) was performed to identifythe potential cause. The results are expressed as hazard ratios orrisk ratios, with their corresponding 95% confidence intervals. Results: The final analysis included four trials comprising 844 patients. The results revealed longer PFS and TTP, and higher ORRand clinical benefit rates in patients receiving sorafenib combinedwith chemotherapy compared to those receiving chemotherapyand placebo. OS and DOR were similar in the two groups. Meanwhile,the incidence of some adverse effects, including hand-footskin reaction/hand-foot syndrome, diarrhea, rash, and hypertension,were significantly higher in the sorafenib arm. Conclusion:Sorafenib combined with chemotherapy may prolong PFS andTTP. This treatment was associated with manageable toxicities,but frequent dose interruptions and reductions were required.

Biocatalysis and Fermentation Technology : Purification and Characterization of a Thermostable Xylanase from Paenibacillus sp. NF1 and its Application in Xylooligosaccharides Production

( Hong Chen Zheng ),( Ming Zhe Sun ),( Ling Cai Meng ),( Hai Sheng Pei ),( Xiu Qing Zhang ),( Zheng Yan ),( Wen Hui Zeng ),( Jing Sheng Zhang ),( Jin Rong Hu ),( Fu Ping Lu ),( Jun She Sun ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.4

High levels of extracellular xylanase activity (211.79 IU/mg) produced by Paenibacillus sp. NF1 were detected when it was submerged-cultured. After three consecutive purification steps using Octyl-Sepharose, Sephadex G75, and Q-Sepharose columns, a thermostable xylanase (XynNF) was purified to homogeneity and showed a molecular mass of 37 kDa according to SDS-PAGE. The specific activity of the purified XynNF was up to 3,081.05 IU/mg with a 14.55-fold purification. The activity of XynNF was stimulated by Ca2+, Ba2+, DTT, and β-mercaptoethanol, but was inhibited by Fe3+, Zn2+, Fe2+, Cu2+, SDS, and EDTA. The purified XynNF displayed a greater affinity for oat spelt xylan with the maximal enzymatic activity at 60°C and pH 6.0. XynNF, which was shown to be cellulose-free, with high stability at high temperature (70°C-80°C) and low pH range (pH 4.0-7.0), is potentially valuable for various industrial applications. The enzyme hydrolyzed oat spelt xylan to yield mainly xylooligosaccharides (95.8%) of 2-4 degree of polymerization (DP2-4). Moreover, the majority of the xylooligosacharides (DP2- 4) products was xylobiose (61.5%). The thermostable xylanase (XynNF) thus seems potentially usefull in the production of xylooligosaccharides.

Production of Recombinant Humanized Anti-HBsAg Fab Fragmentfrom Pichia pastoris by Fermentation

Zhang Qing,Rao Guirong,Deng Ning,Xiang Junjian,Xiong Sheng,Chen Wenyin,Wang Xunzhang 한국생화학분자생물학회 2005 BMB Reports Vol.38 No.3

Family with Sequence Similarity 83 Member H Promotes the Viability and Metastasis of Cervical Cancer Cells and Indicates a Poor Prognosis

Chao Chen,Hua-Feng Li,Yu-Jie Hu,Meng-Jie Jiang,Qing-Sheng Liu,Jia Zhou 연세대학교의과대학 2019 Yonsei medical journal Vol.60 No.7

Purpose: Family with sequence similarity 83 member H (FAM83H) plays key roles in tumorigenesis. However, the specific rolesof FAM83H in cervical cancer (CC) have not been well studied. Materials and Methods: The RNA-seq data of 306 CC tissues and three normal samples downloaded from The Cancer GenomeAtlas were used to analyze the expression of FAM83H. The Kaplan-Meier method was used to draw survival curves. Associationsbetween FAM83H expression and clinicopathological factors were analyzed by chi-square test. Cox proportional hazards modelwas used to analyze prognostic factors. Loss-of-function assays were conducted to discover the biological functions of FAM83Hin cell proliferation, colony formation, invasion, and migration. Real-time Quantitative Reverse Transcription PCR (qRT-PCR)and Western blotting were used to measure the expression levels of FAM83H in CC cell lines. Results: Our results demonstrated that FAM83H is overexpressed in CC tissues and that high FAM83H expression is associatedwith worse overall survival (OS). High FAM83H expression in CC was associated with clinical stage, pathologic tumor, and pathologicnode. Univariate analysis suggested that FAM83H expression was significantly related to the OS of CC patients. Althoughmultivariate analysis showed that FAM83H expression was not an independent prognostic factor for the OS of CC patients, the effectsof FAM83H on CC cell growth and motility was significant. Loss-of-function experiments demonstrated that knockdown ofFAM83H inhibited proliferation, colony formation, migration, and invasion of CC cells by inactivating PI3K/AKT pathway. Conclusion: FAM83H might play a crucial role in CC progression and could act as a novel therapeutic target in CC.

Analysis on Double Rain Belts of a Rainstorm in Liaoning

YANG Qing,YAN Qi,CHEN Li-qiang,GAO Song-ying,LI Shuang,CUI Sheng-quan,LU Bing-hong 한국기상학회 2015 한국기상학회 학술대회 논문집 Vol.2015 No.10

PREPARATION OF CISPLATIN COMPOSITE MICRO/NANOFIBERS AND ANTITUMOR ACTIVITY IN VITRO AGAINST HUMAN TUMOR spc-a-1 CELLS

PING CHEN,QING-SHENG WU,YA-PING DING,ZI-CHUN ZHU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2011 NANO Vol.6 No.4

In this paper, the cisplatin composite micro/nanofibers were prepared by electrospinning. Average diameter of the typical products was about 700 nm, and cisplatins were incorporated in biodegradable poly (L-lactic acid) fibers. The controlled release of cisplatin can be gained for long time. The possible mechanisms of cisplatin release in the PBS and the PBS with proteinase K were discussed. 3-(4, 5)-dimethylthiahiazo-(-z-y1)-3, 5-di-phenytetrazoliumromide (MTT) method was used to test antitumor activities in vitro against human lung tumor spc-a-1 cells. When incubation time was 24 h, the same content of cisplatin from virgin cisplatin and the composite fibers has almost equal antitumor activity in vitro. However, when incubation time was 48 h, the composite fibers show much higher antitumor activity than the virgin cisplatin. The system may be useful in the postoperative local chemotherapy and have clinical applications as an implantable drug for tumor in the future.